National Environmental Change Information System Case Study

NASA Technical Reports Server (NTRS)

Goodman, S. J.; Ritschard, R.; Estes, M. G., Jr.; Hatch, U.

2001-01-01

The Global Hydrology and Climate Center and NASA's Marshall Space Flight Center conducted a fact-finding case study for the Data Management Working Group (DMWG), now referred to as the Data and Information Working Group (DIWG), of the U.S. Global Change Research Program (USGCRP) to determine the feasibility of an interagency National Environmental Change Information System (NECIS). In order to better understand the data and information needs of policy and decision makers at the national, state, and local level, the DIWG asked the case study team to choose a regional water resources issue in the southeastern United States that had an impact on a diverse group of stakeholders. The southeastern United States was also of interest because the region experiences interannual climatic variations and impacts due to El Nino and La Nina. Jointly, with input from the DIWG, a focus on future water resources planning in the Apalachicola-Chattahoochee-Flint (ACF) River basins of Alabama, Georgia, and Florida was selected. A tristate compact and water allocation formula is currently being negotiated between the states and U.S. Army Corps of Engineers (COE) that will affect the availability of water among competing uses within the ACF River basin. All major reservoirs on the ACF are federally owned and operated by the U.S. Army COE. A similar two-state negotiation is ongoing that addresses the water allocations in the adjacent Alabama-Coosa-Tallapoosa (ACT) River basin, which extends from northwest Georgia to Mobile Bay. The ACF and ACT basins are the subject of a comprehensive river basin study involving many stakeholders. The key objectives of this case study were to identify specific data and information needs of key stakeholders in the ACF region, determine what capabilities are needed to provide the most practical response to these user requests, and to identify any limitations in the use of federal data and information. The NECIS case study followed the terms of reference developed by the interagency DIWG. The case study "lessons learned" and "key findings" offer guidelines and considerations to the DMWG for the development and implementation of a NECIS that would support the data and information needs of policy and decision makers at the national, state, and local level.

Arthropods in Decomposing Wood of the Atchafalaya River Basin

Treesearch

B.G. Lockaby; B.D. Keeland; John A. Stanturf; M.D. Rice; G. Hodges; R.M. Governo

2002-01-01

Changes in arthropod populations (numbers of individuals identified to the family level in most cases) were studied during the decomposition of coarse woody debris (CWD) in the Atchafalaya River Basin of Louisiana. The arthropod study was linked with a CWD decomposition study installed after disturbance by Hurricane Andrew. Arthropod numbers were compared between two...

Distinguishing the Source of Natural Gas Accumulations with a Combined Gas and Co-produced Formation Water Geochemical Approach: a Case Study from the Appalachian Basin

EPA Pesticide Factsheets

The purpose of this study is to discuss the use of gas and co-produced formation water geochemistry for identifying the source of natural gas and present gas geochemistry for the northern Appalachian Basin.

Characterization of shallow groundwater quality in the Lower St. Johns River Basin: a case study

Treesearch

Ying Ouyang; Jia-En Zhang; Prem Parajuli

2013-01-01

Characterization of groundwater quality allows the evaluation of groundwater pollution and provides information for better management of groundwater resources. This study characterized the shallow groundwater quality and its spatial and seasonal variations in the Lower St. Johns River Basin, Florida, USA, under agricultural, forest, wastewater, and residential land...

Palaeogeographic reconstruction of sandstones using weighted mean grain-size maps, with examples from the Karoo Basin (South Africa) and the Sydney Basin (Australia)

NASA Astrophysics Data System (ADS)

le Roux, J. P.

1992-12-01

Although sandstone grain-size maps can be a powerful means of reconstructing ancient depositional environments, they have rarely been used in the past. In this paper, two case studies are presented to illustrate the potential of this technique where other, more conventional methods may not be applicable. In the first case, a braided to anastomosing river system in the Triassic Molteno Formation of the South African Karoo Basin is examined. The weighted mean grain-size map clearly portrays the distribution of channels and islands and compares very well with other methods of reconstruction. The second case study examines an offshore shoal in the Permian Nowra Sandstone of the Sydney Basin in Australia. Here the grain-size map shows a north-northeasterly trend parallel to the orientation of the shoal, with a zone of coarsest grains displaced to the east of the shoal crest. This probably reflects the location of the breaker zone. As grain size is an important factor controlling the porosity and permeability of sediments, these maps can provide very useful information when exploring for epigenetic, stratabound ore deposits such as uranium, or planning production wells for oil and gas.

Magnetic fabrics in tectonically inverted sedimentary basins: a review

NASA Astrophysics Data System (ADS)

García-Lasanta, Cristina; Román-Berdiel, Teresa; Casas-Sainz, Antonio; Oliva-Urcia, Belén; Soto, Ruth; Izquierdo-Llavall, Esther

2017-04-01

Magnetic fabric studies in sedimentary rocks were firstly focused on strongly deformed tectonic contexts, such as fold-and-thrust belts. As measurement techniques were improved by the introduction of high-resolution equipments (e.g. KLY3-S and more recent Kappabridge susceptometers from AGICO Inc., Czech Republic), more complex tectonic contexts could be subjected to anisotropy of magnetic susceptibility (AMS) analyses in order to describe the relationship between tectonic conditions and the orientation and shape of the resultant magnetic ellipsoids. One of the most common complex tectonic frames involving deformed sedimentary rocks are inverted extensional basins. In the last decade, multiple AMS studies revealed that the magnetic fabric associated with the extensional stage (i.e. a primary magnetic fabric) can be preserved despite the occurrence of subsequent deformational processes. In these cases, magnetic fabrics may provide valuable information about the geometry and kinematics of the extensional episode (i.e. magnetic ellipsoids with their minimum susceptibility axis oriented perpendicular to the deposit plane and magnetic lineation oriented parallel to the extension direction). On the other hand, several of these studies have also determined how the subsequent compressional stage can modify the primary extensional fabric in some cases, particularly in areas subjected to more intense deformation (with development of compression-related cleavage). In this contribution we present a compilation of AMS studies developed in sedimentary basins that underwent different degree of tectonic inversion during their history, in order to describe the relationship of this degree of deformation and the degree of imprint that tectonic conditions have in the previous magnetic ellipsoid (primary extension-related geometry). The inverted basins included in this synthesis are located in the Iberian Peninsula and show: i) weak deformation (W Castilian Branch and Maestrazgo basin, Iberian Range); ii) transport along the hangingwall of thrusts with very slight internal deformation (Organyà basin, Central Pyrenees); iii) record of incipient compressive strain and foliation development (Cabuerniga basin, Basque-Cantabrian Basin; Lusitanian basin, W Portugal); iv) complete inversion associated with a remarkable transport along the hangingwall of thrusts and relatively large internal deformation (Cameros basin, Iberian Range); and v) major folding and flattening linked to foliation (Mauléon basin, Northern Pyrenees; Nogueres unit, Pyrenean Axial Zone).

Case study applications of the BASINS climate assessment tool (CAT)

EPA Science Inventory

This EPA report will illustrate the application of different climate assessment capabilities within EPA’s BASINS modeling system for assessing a range of potential questions about the effects of climate change on streamflow and water quality in different watershed settings and us...

On the soil moisture estimate at basin scale in Mediterranean basins with the ASAR sensor: the Mulargia basin case study

NASA Astrophysics Data System (ADS)

Fois, Laura; Montaldo, Nicola

2017-04-01

Soil moisture plays a key role in water and energy exchanges between soil, vegetation and atmosphere. For water resources planning and managementthesoil moistureneeds to be accurately and spatially monitored, specially where the risk of desertification is high, such as Mediterranean basins. In this sense active remote sensors are very attractive for soil moisture monitoring. But Mediterranean basinsaretypicallycharacterized by strong topography and high spatial variability of physiographic properties, and only high spatial resolution sensorsare potentially able to monitor the strong soil moisture spatial variability.In this regard the Envisat ASAR (Advanced Synthetic Aperture Radar) sensor offers the attractive opportunity ofsoil moisture mapping at fine spatial and temporal resolutions(up to 30 m, every 30 days). We test the ASAR sensor for soil moisture estimate in an interesting Sardinian case study, the Mulargia basin withan area of about 70 sq.km. The position of the Sardinia island in the center of the western Mediterranean Sea basin, its low urbanization and human activity make Sardinia a perfect reference laboratory for Mediterranean hydrologic studies. The Mulargia basin is a typical Mediterranean basinin water-limited conditions, and is an experimental basin from 2003. For soil moisture mapping23 satellite ASAR imagery at single and dual polarization were acquired for the 2003-2004period.Satellite observationsmay bevalidated through spatially distributed soil moisture ground-truth data, collected over the whole basin using the TDR technique and the gravimetric method, in days with available radar images. The results show that ASAR sensor observations can be successfully used for soil moisture mapping at different seasons, both wet and dry, but an accurate calibration with field data is necessary. We detect a strong relationship between the soil moisture spatial variability and the physiographic properties of the basin, such as soil water storage capacity, deep and texture of soils, type and density of vegetation, and topographic parameters. Finally we demonstrate that the high resolution ASAR imagery are an attractive tool for estimating surface soil moisture at basin scale, offering a unique opportunity for monitoring the soil moisture spatial variability in typical Mediterranean basins.

Estimating migratory fish distribution from altitude and basin area: a case study in a large Neotropical river

Treesearch

Jose Ricardo Barradas; Lucas G. Silva; Bret C. Harvey; Nelson F. Fontoura

2012-01-01

1. The objective of this study was to identify longitudinal distribution patterns of large migratory fish species in the Uruguay River basin, southern Brazil, and construct statistical distribution models for Salminus brasiliensis, Prochilodus lineatus, Leporinus obtusidens and Pseudoplatystoma corruscans. 2. The sampling programme resulted in 202 interviews with old...

Insights on the structural control of a Neogene forearc basin in Northern Chile: A geophysical approach

NASA Astrophysics Data System (ADS)

García-Pérez, Tiaren; Marquardt, Carlos; Yáñez, Gonzalo; Cembrano, José; Gomila, Rodrigo; Santibañez, Isabel; Maringue, José

2018-06-01

The comprehensive study of intramountain basins located in the Coastal Cordillera of the continental emergent Andean forearc in Northern Chile, enables the better understanding of the nature and evolution of the upper crustal deformation during the Neogene and Quaternary. A case study is the extensive extensional half-graben Alto Hospicio basin. The basin is cut by the Coastal Cliff, which exposes the deformed Neogene basin fill. Also exposed are several structural systems, some of which affect Quaternary surfaces. The results of the integrated geophysical surveys (Electromagnetic Transient and Gravity) allow us to fully constrain the geometry of the Alto Hospicio basin and the lithological relationship between the subsurface geological units. The structural geology analysis assesses the deformation regimes affecting the faults present in the basin and surrounding area. Altogether evidence a change in the deformation regime from an EW extensional deformation during the Miocene-Pliocene to a NS compression in the Quaternary as is presented in this study. We suggest this deformation change is related to a small change in the convergence vector orientation during the Pliocene.

REGIONAL ASSESSMENT OF FISH HEALTH: A PROTOTYPE METHODOLOGY AND CASE STUDY FOR THE ALBEMARLE-PAMLICO RIVER BASIN, NORTH CAROLINA

EPA Science Inventory

BASE (Basin-Scale Assessments for Sustainable Ecosystems) is a research program developed by the Ecosystems Research Division of the National Exposure Research Laboratory to explore and formulate approaches for assessing the sustainability of ecological resources within watershed...

Integrating global satellite-derived data products as a pre-analysis for hydrological modelling studies: a case study for the Red River Basin

USDA-ARS?s Scientific Manuscript database

With changes in weather patterns and intensifying anthropogenic water use, there is an increasing need for spatio-temporal information on water fluxes and stocks in river basins. The assortment of satellite-derived open-access information sources on rainfall (P) and land use / land cover (LULC) is c...

Variability of extreme rainfall over La Plata Basin and Amazon Basin in South America in model simulations of the 20th century and projections under global warming

NASA Astrophysics Data System (ADS)

Cavalcanti, I. F.

2011-12-01

The two largest river basins in South America are Amazon Basin (AMB) in the tropical region and La Plata Basin (LPB) in subtropical and extratropical regions. Extreme droughts have occurred during this decade in Amazonia region which have affected the transportation, fishing activities with impacts in the local population, and also affecting the forest. Droughts or floods over LPB have impacts on agriculture, hydroelectricity power and social life. Therefore, monthly wet and dry extremes in these two regions have a profound effect on the economy and society. Observed rainfall over Amazon Basin (AMB) and La Plata Basin (LPB) is analyzed in monthly timescale using the Standardized Precipitation Index (SPI), from 1979 to 1999. This period is taken to compare GPCP data with HADCM3 simulations (Hadley Centre) of the 20th century and to analyze reanalyses data which have the contribution of satellite information after 1979. HADCM3 projections using SRES A2 scenario is analyzed in two periods: 2000 to 2020 and 2079 to 2099 to study the extremes frequency in a near future and in a longer timescale. Extreme, severe and moderate cases are identified in the northern and southern sectors of LPB and in the western and eastern sectors of AMB. The main objective is to analyze changes in the frequency of cases, considering the global warming and the associated mechanisms. In the observations for the 20th century, the number of extreme rainy cases is higher than the number of dry cases in both sectors of LPB and AMB. The model simulates this variability in the two sectors of LPB and in the west sector of AMB. In the near future 2000 to 2020 the frequency of wet and dry extremes does not change much in LPB and in the western sector of AMB, but the wet cases increase in the eastern AMB. However, in the period of 2079 to 2099 the projections indicate increase of wet cases in LPB and increase of dry cases in AMB. The influence of large scale features related to Sea Surface Temperature Anomalies, Walker and Hadley circulations, teleconnections, as well as the regional features related to humidity flux are discussed. The extreme droughts of 2005 and 2010 in Amazonia are show to be related to these features.

Groundwater quality in the Colorado River basins, California

USGS Publications Warehouse

Dawson, Barbara J. Milby; Belitz, Kenneth

2012-01-01

Groundwater provides more than 40 percent of California’s drinking water. To protect this vital resource, the State of California created the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The Priority Basin Project of the GAMA Program provides a comprehensive assessment of the State’s groundwater quality and increases public access to groundwater-quality information. Four groundwater basins along the Colorado River make up one of the study areas being evaluated. The Colorado River study area is approximately 884 square miles (2,290 square kilometers) and includes the Needles, Palo Verde Mesa, Palo Verde Valley, and Yuma groundwater basins (California Department of Water Resources, 2003). The Colorado River study area has an arid climate and is part of the Sonoran Desert. Average annual rainfall is about 3 inches (8 centimeters). Land use in the study area is approximately 47 percent (%) natural (mostly shrubland), 47% agricultural, and 6% urban. The primary crops are pasture and hay. The largest urban area is the city of Blythe (2010 population of 21,000). Groundwater in these basins is used for public and domestic water supply and for irrigation. The main water-bearing units are gravel, sand, silt, and clay deposited by the Colorado River or derived from surrounding mountains. The primary aquifers in the Colorado River study area are defined as those parts of the aquifers corresponding to the perforated intervals of wells listed in the California Department of Public Health database. Public-supply wells in the Colorado River basins are completed to depths between 230 and 460 feet (70 to 140 meters), consist of solid casing from the land surface to a depth of 130 of 390 feet (39 to 119 meters), and are screened or perforated below the solid casing. The main source of recharge to the groundwater systems in the Needles, Palo Verde Mesa, and Palo Verde Valley basins is the Colorado River; in the Yuma basin, the main source of recharge is from subsurface flow from the groundwater basins to the west. Groundwater discharge is primarily to pumping wells, evapotranspiration, and, locally, to the Colorado River.

To Tip or Not to Tip: The Case of the Congo Basin Rainforest Realm

NASA Astrophysics Data System (ADS)

Pietsch, S.; Bednar, J. E.; Fath, B. D.; Winter, P. A.

2017-12-01

The future response of the Congo basin rainforest, the second largest tropical carbon reservoir, to climate change is still under debate. Different Climate projections exist stating increase and decrease in rainfall and different changes in rainfall patterns. Within this study we assess all options of climate change possibilities to define the climatic thresholds of Congo basin rainforest stability and assess the limiting conditions for rainforest persistence. We use field data from 199 research plots from the Western Congo basin to calibrate and validate a complex BioGeoChemistry model (BGC-MAN) and assess model performance against an array of possible future climates. Next, we analyze the reasons for the occurrence of tipping points, their spatial and temporal probability of occurrence, will present effects of hysteresis and derive probabilistic spatial-temporal resilience landscapes for the region. Additionally, we will analyze attractors of forest growth dynamics and assess common linear measures for early warning signals of sudden shifts in system dynamics for their robustness in the context of the Congo Basin case, and introduce the correlation integral as a nonlinear measure of risk assessment.

A market-based approach to share water and benefits in transboundary river basins

NASA Astrophysics Data System (ADS)

Arjoon, Diane; Tilmant, Amaury; Herrmann, Markus

2016-04-01

The equitable sharing of benefits in transboundary river basins is necessary to reach a consensus on basin-wide development and management activities. Benefit sharing arrangements must be collaboratively developed to be perceived as efficient, as well as equitable, in order to be considered acceptable to all riparian countries. The current literature falls short of providing practical, institutional arrangements that ensure maximum economic welfare as well as collaboratively developed methods for encouraging the equitable sharing of benefits. In this study we define an institutional arrangement that distributes welfare in a river basin by maximizing the economic benefits of water use and then sharing these benefits in an equitable manner using a method developed through stakeholder involvement. In this methodology (i) a hydro-economic model is used to efficiently allocate scarce water resources to water users in a transboundary basin, (ii) water users are obliged to pay for water, and (iii) the total of these water charges are equitably redistributed as monetary compensation to users. The amount of monetary compensation, for each water user, is determined through the application of a sharing method developed by stakeholder input, based on a stakeholder vision of fairness, using an axiomatic approach. The whole system is overseen by a river basin authority. The methodology is applied to the Eastern Nile River basin as a case study. The technique ensures economic efficiency and may lead to more equitable solutions in the sharing of benefits in transboundary river basins because the definition of the sharing rule is not in question, as would be the case if existing methods, such as game theory, were applied, with their inherent definitions of fairness.

Assessment of habitat threats to shrublands in the Great Basin: a case study

Treesearch

Mary M. Rowland; Lowell H. Suring; Michael J. Wisdom

2010-01-01

The sagebrush (Artemisia spp.) ecosystem is one of the most imperiled in the United States. In the Great Basin ecoregion and elsewhere, catastrophic wildland fires are often followed by the invasion of cheatgrass (Bromus tectorum L.), eliminating or altering millions of hectares of sagebrush and other shrublands. Sagebrush in...

Simulating Water Resource Disputes of Transboundary River: A Case Study of the Zhanghe River Basin, China

NASA Astrophysics Data System (ADS)

Yuan, Liang; He, Weijun; Liao, Zaiyi; Mulugeta Degefu, Dagmawi; An, Min; Zhang, Zhaofang

2018-01-01

Water resource disputes within transboundary river basin has been hindering the sustainable use of water resources and efficient management of environment. The problem is characterized by a complex information feedback loop that involves socio-economic and environmental systems. This paper presents a system dynamics based model that can simulate the dynamics of water demand, water supply, water adequacy and water allocation instability within a river basin. It was used for a case study in the Zhanghe River basin of China. The base scenario has been investigated for the time period between 2000 and 2050. The result shows that the Chinese national government should change the water allocation scheme of downstream Zhanghe River established in 1989, more water need to be allocated to the downstream cities and the actual allocation should be adjusted to reflect the need associated with the socio-economic and environmental changes within the region, and system dynamics improves the understanding of concepts and system interactions by offering a comprehensive and integrated view of the physical, social, economic, environmental, and political systems.

Strategic planning for instream flow restoration: a case study of potential climate change impacts in the central Columbia River basin.

PubMed

Donley, Erin E; Naiman, Robert J; Marineau, Mathieu D

2012-10-01

We provide a case study prioritizing instream flow restoration activities by sub-basin according to the habitat needs of Endangered Species Act (ESA)-listed salmonids relative to climate change in the central Columbia River basin in Washington State (USA). The objective is to employ scenario analysis to inform and improve existing instream flow restoration projects. We assess the sensitivity of late summer (July, August, and September) flows to the following scenario simulations - singly or in combination: climate change, changes in the quantity of water used for irrigation and possible changes to existing water resource policy. Flows for four sub-basins were modeled using the Water Evaluation and Planning system (WEAP) under historical and projected conditions of 2020 and 2040 for each scenario. Results indicate that Yakima will be the most flow-limited sub-basin with average reductions in streamflow of 41% under climate conditions of 2020 and 56% under 2040 conditions; 1.3-2.5 times greater than those of other sub-basins. In addition, irrigation plays a key role in the hydrology of the Yakima sub-basin - with flow reductions ranging from 78% to 90% under severe to extreme (i.e., 20-40%) increases in agricultural water use (2.0-4.4 times the reductions in the other sub-basins). The Yakima and Okanogan sub-basins are the most responsive to simulations of flow-bolstering policy change (providing salmon with first priority water allocation and at biologically relevant flows), as demonstrated by 91-100% target flows attained. The Wenatchee and Methow sub-basins do not exhibit similar responsiveness to simulated policy changes. Considering climate change only, we conclude that flow restoration should be prioritized first in the Yakima and Wenatchee sub-basins, and second in the Okanogan and Methow. Considering both climate change and possible policy changes, we recommend that the Yakima sub-basin receive the highest priority for flow restoration activities to sustain critical instream habitat for ESA-listed salmonids. © 2012 Blackwell Publishing Ltd.

Precipitation Based Malaria Patterns in the Amazon -- Will Deforestation Alter Risk?

NASA Astrophysics Data System (ADS)

Olson, S. H.; Durieux, L.; Elguero, E.; Foley, J.; Gagnon, R.; Guegan, J.; Patz, J.

2007-12-01

The World Health Organization, estimates that forty-two percent of malaria cases are "associated with policies and practices regarding land use, deforestation, water resource management, settlement siting and modified house design". This estimate was drawn from expert opinion and studies performed at local scales, but little research has investigated the cumulative impacts of land use and land cover changes occurring in the Amazon Basin on malaria. Much less is understood about the impact of changing land use and subsequent precipitation regimes on malaria risk. To understand how land use practices may alter malaria patterns in the Basin we present an analysis of municipio (n=755) malaria case data and monthly precipitation patterns between 1996 and 1999. Climate data originated from the CRU TS 2.1 half-degree grid resolution climate data set. We present a hierarchical (random coefficients) log-linear Poisson model relating malaria incidence to precipitation for both municipos and states. At the Basin scale precipitation and cases show strong relationships. Precipitation and cases are asynchronous across the period of observation, but detailed inspection of states and individual municipios reveal geographic dependencies of precipitation and malaria incidence. Future research will link the patterns of precipitation and malaria to anticipated changes in climate from deforestation in the Basin.

Application of the environmental Gini coefficient in allocating water governance responsibilities: a case study in Taihu Lake Basin, China.

PubMed

Zhou, Shenbei; Du, Amin; Bai, Minghao

2015-01-01

The equitable allocation of water governance responsibilities is very important yet difficult to achieve, particularly for a basin which involves many stakeholders and policymakers. In this study, the environmental Gini coefficient model was applied to evaluate the inequality of water governance responsibility allocation, and an environmental Gini coefficient optimisation model was built to achieve an optimal adjustment. To illustrate the application of the environmental Gini coefficient, the heavily polluted transboundary Taihu Lake Basin in China, was chosen as a case study. The results show that the original environmental Gini coefficient of the chemical oxygen demand (COD) was greater than 0.2, indicating that the allocation of water governance responsibilities in Taihu Lake Basin was unequal. Of seven decision-making units, three were found to be inequality factors and were adjusted to reduce the water pollutant emissions and to increase the water governance inputs. After the adjustment, the environmental Gini coefficient of the COD was less than 0.2 and the reduction rate was 27.63%. The adjustment process provides clear guidance for policymakers to develop appropriate policies and improve the equality of water governance responsibility allocation.

Groundwater quality in the Coastal Los Angeles Basin, California

USGS Publications Warehouse

Fram, Miranda S.; Belitz, Kenneth

2012-01-01

The Coastal Los Angeles Basin study unit is approximately 860 square miles and consists of the Santa Monica, Hollywood, West Coast, Central, and Orange County Coastal Plain groundwater basins (California Department of Water Resources, 2003). The basins are bounded in part by faults, including the Newport-Inglewood fault zone, and are filled with Holocene-, Pleistocene-, and Pliocene-age marine and alluvial sediments. The Central Basin and Orange County Coastal Plain are divided into a forebay zone on the northeast and a pressure zone in the center and southwest. The forebays consist of unconsolidated coarser sediment, and the pressure zones are characterized by lenses of coarser sediment divided into confined to semi-confined aquifers by lenses of finer sediments. The primary aquifer system in the study unit is defined as those parts of the aquifer system corresponding to the perforated intervals of wells listed in the California Department of Public Health (CDPH) database of public-supply wells. The majority of public-supply wells are drilled to depths of 510 to 1,145 feet, consist of solid casing from the land surface to a depth of about 300 to 510 feet, and are perforated below the solid casing. Water quality in the primary aquifer system may differ from that in the shallower and deeper parts of the aquifer systems.

Lymphoscintigraphy mapping of truncal malignant melanoma: A study of 212 patients at the Christie NHS Foundation Trust.

PubMed

El Muntasar, Ahmed; Oudit, Deems

2017-01-01

Malignant melanoma (MM) on the trunk, because of its anatomical location, has multiple potential lymphatic basins to which to drain. The aim of this study is to map the location of the sentinel lymph node (SLN) on the basis of the anatomical location of the primary malignant melanoma on the trunk. Patients diagnosed with MM on the trunk who had undergone a SLN biopsy from January 2006 to March 2015 were identified in the Christie NHS Foundation Trust through a computer database search. The anterior and posterior surfaces of the trunk were divided into four sections each. A total of 212 patients were evaluated. MM was more common on the posterior trunk, accounting for 73% of cases, and 57% of melanomas were on the right side of the trunk. The axillary basins were involved in drainage in 91.5% of all truncal melanomas. Drainage was to a single lymphatic basin in 68.3% of cases. The incidence of drainage to multiple lymphatic basins was not uniform for the anterior and posterior surfaces of the trunks. One-third of MM on the posterior surface of the trunk will drain to multiple basins. Around 50% of the melanomas of the upper back drain to a contralateral basin. Independent of the location of the MM, the axillary basins were the most common location of drainage, with a total of 91% of the cohort. Therefore, the location of the SLN could be predicted, depending on the location of the MM on the trunk. Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.

Incentive compatibility and conflict resolution in international river basins: A case study of the Nile Basin

NASA Astrophysics Data System (ADS)

Wu, Xun; Whittington, Dale

2006-02-01

Nation-states rarely go to war over water, but it is equally rare that water conflicts in an international river basin are resolved through cooperation among the riparian countries that use the shared resources. Gains from cooperation will mean little to individual riparians unless the required cooperative behaviors are incentive compatible. Cooperative game theory offers useful insights for assessing cooperative solutions for water conflicts in international river basins. Applying cooperative game theory concepts such as core, nucleolus, and Shapley value to Nile water conflicts, we examine the incentive structure of both cooperative and noncooperative strategies for different riparian countries and establish some baseline conditions for incentive-compatible cooperation in the Nile basin.

Modeling Study of Winter Ozone Pollution in Uintah Basin: A Case Study of January 15-31 in 2013 Using WRF-CAMx.

NASA Astrophysics Data System (ADS)

Tran, T. T.; Tran, H. N. Q.; Mansfield, M. L.; Lyman, S. N.

2014-12-01

Since elevated ozone concentrations (>75ppb) were first detected in Uintah Basin in 2009, winter ozone pollution in Uintah Basin (Eastern Utah) has drawn researchers' attention in this region. Joint research efforts among several research groups have been undertaken to study this topic (UBOS, 2012; 2013; 2014); yet this phenomenon is still not completely understood. For example, modeling studies still face problems such as errors in emission inventories and inappropriate meteorological and chemical modeling parameterizations for winter conditions in the Uintah Basin. In this study, the SMOKE-WRF-CAMx model platform (grid resolution of 1.3km) was used to simulate ozone formation in the basin during Jan 15-31 in 2013 to compare the impacts of current bottom-up versus top-down emission inventories on modeled ozone concentrations. Different VOC emission profiles for oil and gas emissions that have been applied in various studies were also examined in CAMx and compared with available monitoring data to determine the representative profile for future studies.

Pluvial lakes in the Great Basin of the western United States: a view from the outcrop

USGS Publications Warehouse

Reheis, Marith C.; Adams, Kenneth D.; Oviatt, Charles G.; Bacon, Steven N.

2014-01-01

Paleo-lakes in the western United States provide geomorphic and hydrologic records of climate and drainage-basin change at multiple time scales extending back to the Miocene. Recent reviews and studies of paleo-lake records have focused on interpretations of proxies in lake sediment cores from the northern and central parts of the Great Basin. In this review, emphasis is placed on equally important studies of lake history during the past ∼30 years that were derived from outcrop exposures and geomorphology, in some cases combined with cores. Outcrop and core records have different strengths and weaknesses that must be recognized and exploited in the interpretation of paleohydrology and paleoclimate. Outcrops and landforms can yield direct evidence of lake level, facies changes that record details of lake-level fluctuations, and geologic events such as catastrophic floods, drainage-basin changes, and isostatic rebound. Cores can potentially yield continuous records when sampled in stable parts of lake basins and can provide proxies for changes in lake level, water temperature and chemistry, and ecological conditions in the surrounding landscape. However, proxies such as stable isotopes may be influenced by several competing factors the relative effects of which may be difficult to assess, and interpretations may be confounded by geologic events within the drainage basin that were unrecorded or not recognized in a core. The best evidence for documenting absolute lake-level changes lies within the shore, nearshore, and deltaic sediments that were deposited across piedmonts and at the mouths of streams as lake level rose and fell. We review the different shorezone environments and resulting deposits used in such reconstructions and discuss potential estimation errors. Lake-level studies based on deposits and landforms have provided paleohydrologic records ranging from general changes during the past million years to centennial-scale details of fluctuations during the late Pleistocene and Holocene. Outcrop studies have documented the integration histories of several important drainage basins, including the Humboldt, Amargosa, Owens, and Mojave river systems, that have evolved since the Miocene within the active tectonic setting of the Great Basin; these histories have influenced lake levels in terminal basins. Many pre-late Pleistocene lakes in the western Great Basin were significantly larger and record wetter conditions than the youngest lakes. Outcrop-based lake-level data provide important checks on core-based proxy interpretations; we discuss four such comparisons. In some cases, such as for Lakes Owens and Manix, outcrop and core data synthesis yields stronger and more complete records; in other cases, such as for Bonneville and Lahontan, conflicts point toward reconsideration of confounding factors in interpretation of core-based proxies.

Prediction of hydrocarbons in sedimentary basins

USGS Publications Warehouse

Harff, J.E.; Davis, J.C.; Eiserbeck, W.

1993-01-01

To estimate the undiscovered hydrocarbon potential of sedimentary basins, quantitative play assessments specific for each location in a region may be obtained using geostatistical methods combined with the theory of classification of geological objects, a methodology referred to as regionalization. The technique relies on process modeling and measured borehole data as well as probabilistic methods to exploit the relationship between geology (the "predictor") and known hydrocarbon productivity (the "target") to define prospective stratigraphic intervals within a basin. It is demonstrated in case studies from the oil-producing region of the western Kansas Pennsylvanian Shelf and the gas-bearing Rotliegend sediments of the Northeast German Basin. ?? 1993 International Association for Mathematical Geology.

A Kaluza-Klein subtractor

NASA Astrophysics Data System (ADS)

Jana, Sanjib; Krishnan, Chethan

2014-05-01

We generalize the results of arXiv:1212.1875 and arXiv:1212.6919 on attraction basins and their boundaries to the case of a specific class of rotating black holes, namely the ergo-free branch of extremal black holes in Kaluza-Klein theory. We find that exact solutions that span the attraction basin can be found even in the rotating case by appealing to certain symmetries of the equations of motion. They are characterized by two asymptotic parameters that generalize those of the non-rotating case, and the boundaries of the basin are spinning versions of the (generalized) subtractor geometry. We also give examples to illustrate that the shape of the attraction basin can drastically change depending on the theory.

A Regionalized Flow Duration Curve Method to Predict Streamflow for Ungauaged Basins: A Case Study of the Rappahannock Watershed in Virginia, USA

EPA Science Inventory

A method to predict streamflow for ungauged basins of the Mid-Atlantic Region, USA was applied to the Rappahannock watershed in Virginia, USA. The method separates streamflow time series into magnitude and time sequence components. It uses the regionalized flow duration curve (RF...

FOXO3 variants are beneficial for longevity in Southern Chinese living in the Red River Basin: A case-control study and meta-analysis

PubMed Central

Sun, Liang; Hu, Caiyou; Zheng, Chenguang; Qian, Yu; Liang, Qinghua; Lv, Zeping; Huang, Zezhi; Qi, KeYan; Gong, Huan; Zhang, Zheng; Huang, Jin; Zhou, Qin; Yang, Ze

2015-01-01

Forkhead box class O (FOXO) transcription factors play a crucial role in longevity across species. Several polymorphisms in FOXO3 were previously reported to be associated with human longevity. However, only one Chinese replication study has been performed so far. To verify the role of FOXO3 in southern Chinese in the Red River Basin, a community-based case-control study was conducted, and seven polymorphisms were genotyped in 1336 participants, followed by a meta-analysis of eight case-control studies that included 5327 longevity cases and 4608 controls. In our case-control study, we found rs2802288*A and rs2802292*G were beneficial to longevity after Bonferroni correction (pallele = 0.005, OR = 1.266; pallele = 0.026, OR = 1.207). In addition, in the longevity group, carriers with rs2802288*A and rs2802292*G presented reduced HbA1c (p = 0.001), and homozygotes of rs2802292*GG presented improved HOMA–IR (p = 0.014). The meta-analysis further revealed the overall contribution of rs2802288*A and rs2802292*G to longevity. However, our stratified analysis revealed that rs2802292*G might act more strongly in Asians than Europeans, for enhancement of longevity. In conclusion, our study provides convincing evidence for a significant association between the rs2802288*A and rs2802292*G gene variants in FOXO3 and human longevity, and adds the Southern Chinese in the Red River Basin to the growing number of human replication populations. PMID:25913413

FOXO3 variants are beneficial for longevity in Southern Chinese living in the Red River Basin: A case-control study and meta-analysis.

PubMed

Sun, Liang; Hu, Caiyou; Zheng, Chenguang; Qian, Yu; Liang, Qinghua; Lv, Zeping; Huang, Zezhi; Qi, KeYan; Gong, Huan; Zhang, Zheng; Huang, Jin; Zhou, Qin; Yang, Ze

2015-04-27

Forkhead box class O (FOXO) transcription factors play a crucial role in longevity across species. Several polymorphisms in FOXO3 were previously reported to be associated with human longevity. However, only one Chinese replication study has been performed so far. To verify the role of FOXO3 in southern Chinese in the Red River Basin, a community-based case-control study was conducted, and seven polymorphisms were genotyped in 1336 participants, followed by a meta-analysis of eight case-control studies that included 5327 longevity cases and 4608 controls. In our case-control study, we found rs2802288*A and rs2802292*G were beneficial to longevity after Bonferroni correction (pallele = 0.005, OR = 1.266; pallele = 0.026, OR = 1.207). In addition, in the longevity group, carriers with rs2802288*A and rs2802292*G presented reduced HbA1c (p = 0.001), and homozygotes of rs2802292*GG presented improved HOMA-IR (p = 0.014). The meta-analysis further revealed the overall contribution of rs2802288*A and rs2802292*G to longevity. However, our stratified analysis revealed that rs2802292*G might act more strongly in Asians than Europeans, for enhancement of longevity. In conclusion, our study provides convincing evidence for a significant association between the rs2802288*A and rs2802292*G gene variants in FOXO3 and human longevity, and adds the Southern Chinese in the Red River Basin to the growing number of human replication populations.

The effects of drainage basin geomorphometry on minimum low flow discharge: the study of small watershed in Kelang River Valley in Peninsular Malaysia.

PubMed

Yunus, Ahmad Jailani Muhamed; Nakagoshi, Nobukazu; Salleh, Khairulmaini Osman

2003-03-01

This study investigate the relationships between geomorphometric properties and the minimum low flow discharge of undisturbed drainage basins in the Taman Bukit Cahaya Seri Alam Forest Reserve, Peninsular Malaysia. The drainage basins selected were third-order basins so as to facilitate a common base for sampling and performing an unbiased statistical analyses. Three levels of relationships were observed in the study. Significant relationships existed between the geomorphometric properties as shown by the correlation network analysis; secondly, individual geomorphometric properties were observed to influence minimum flow discharge; and finally, the multiple regression model set up showed that minimum flow discharge (Q min) was dependent of basin area (AU), stream length (LS), maximum relief (Hmax), average relief (HAV) and stream frequency (SF). These findings further enforced other studies of this nature that drainage basins were dynamic and functional entities whose operations were governed by complex interrelationships occurring within the basins. Changes to any of the geomorphometric properties would influence their role as basin regulators thus influencing a change in basin response. In the case of the basin's minimum low flow, a change in any of the properties considered in the regression model influenced the "time to peak" of flow. A shorter time period would mean higher discharge, which is generally considered the prerequisite to flooding. This research also conclude that the role of geomorphometric properties to control the water supply within the stream through out the year even though during the drought and less precipitations months. Drainage basins are sensitive entities and any deteriorations involve will generate reciprocals and response to the water supply as well as the habitat within the areas.

A new eco-hydrological distributed model for the predictions of the climate change impact on water resources of Mediterranean water-limited basins: the Mulargia basin case study in Sardinia.

NASA Astrophysics Data System (ADS)

Sarigu, Alessio; Montaldo, Nicola

2017-04-01

In the last three decades, climate change and human activities increased desertification process in Mediterranean regions, with dramatic consequences for agriculture and water availability. For instance in the main reservoir systems in Sardinia the average annual runoff in the latter part of the 20th century decreased of more than 50% compared with the previous period, while the precipitation over the Sardinia basin has decreased, but not at such a drastic rate as the discharge, with an high precipitation elasticity to streamflow, highlighting the key role of the rainfall seasonality on runoff production. IPCC climate change scenarios predict a further decrease of winter rainfall, which is the key term for runoff production in these typical Mediterranean climate basins, and air temperature increase, which can potentially impact on evapotranspiration, soil moisture and runoff. Only the use of an accurate ecohydrological physically based distributed model allow to well predict the impact of the climate change scenarios on the basin water resources. A new eco-hydrological model is developed that couples a distributed hydrological model of and a vegetation dynamic model (VDM). The hydrological model estimates the soil water balance of each basin cell using the force-restore method, the Philips model for infiltration estimate and the Penman-Monteith equation for evapotranspiration estimate. The VDM evaluates the changes in biomass over time for each cell and provides the leaf area index (LAI), which is then used by the hydrological model for evapotranspiration and rainfall interception estimates. Case study is the Mulargia basin (Sardinia, basin area of about 70 km2), where an extended field campaign started from 2003, with rain and discharge data observed at the basin outlet, periodic field measurements of soil moisture and LAI all over the basin, and evapotraspiration estimates using an eddy correlation based tower. The Mulargia basin case study is a very interesting laboratory of Mediterranean basins, thanks to its typical Mediterranean climate, its typical physiografic characteristics, its low human activities and influences and its attractive hydrologic database. The model has been successfully and deeply calibrated for the 2003 and validated for the 2004-2005 period, using both field data and satellite Modis data. Three future climate change scenarios has been generated using a stochastic model (Richardson, 1991), opportunely adapted for accounting the future changes of climate conditions. The scenarios (A1-A1B-A2) assume that in the next century there will be a drastic reduction of precipitation (with maximum reduction of 30% in A2) and that will continue the warming process. A reduction of soil moisture (about 40%) is predicted, especially during winter month and also the LAI will drastically decrease (more than 50% for woody vegetation and 75% for grass especially during the spring). Runoff will decrease even more (up to 70%) during the winter season, which is the key season for the water resource management and planning of these Mediterranean basins. These results anticipate a dramatic reduction of water resources availability, a change of vegetation species and ecosystems, increasing the desertification process in this typical Mediterranean area.

[Ecological risk assessment of typical karst basin based on land use change: A case study of Lijiang River basin, Southern China].

PubMed

Hu, Jin Long; Zhou, Zhi Xiang; Teng, Ming Jun; Luo, Nan

2017-06-18

Taking Lijiang River basin as study area, and based on the remote sensing images of 1973, 1986, 2000 and 2013, the land-use data were extracted, the ecological risk index was constructed, and the characteristics of spatiotemporal variation of ecological risk were analyzed by "3S" technique. The results showed that land use structure of Lijiang River basin was under relatively reasonable state and it was constantly optimizing during 1973-2013. Overall, the ecological risk of Lijiang River basin was maintained at a low level. Lowest and lower ecological risk region was dominant in Lijiang River basin, but the area of highest ecological risk expanded quickly. The spatial distribution of ecological risk was basically stable and showed an obvious ring structure, which gra-dually decreased from the axis of Xingan County Town-Lingchuan County Town-Guilin City-Yangshuo County Town to other regions. Region with lowest ecological risk mainly distributed in natural mountain forest area of the north and mid-eastern parts of Lijiang River basin, and region with highe-st ecological risk concentrated in Guilin City. The ecological risk distribution of Lijiang River basin presented significant slope and altitude differences, and it decreased with increasing slope and altitude. During the study period, the area of low ecological risk converted to high ecological risk gra-dually decreased and vice versa. On the whole, the ecological risk tended to decline rapidly in the Lijiang River basin.

The Hack's law applied to young volcanic basin: the Tahiti case

NASA Astrophysics Data System (ADS)

Ye, F.; Sichoix, L.; Barriot, J.; Serafini, J.

2010-12-01

We study the channel morphology over the Tahiti island from the Hack’s law perspective. The Hack’s law is an empirical power relationship between basin drainage area and the length of its main channel. It had also been shown that drainage area becomes more elongate with increasing basin size. For typical continental basins, the exponent value lies between 0.47 for basins larger than 260,000 km2 and 0.7 for those spanning less than 20,720 km2 (Muller, 1973). In Tahiti, we extracted 27 principal basins ranging from 7 km2 to 90 km2 from a Digital Terrain Model of the island with a 5 m-resolution. We demonstrate that the Hack’s law still apply for such small basins (correlation coefficient R2=0.7) with an exponent value being approximately 0.5. It appears that the exponent value is influenced by the local geomorphic condition, and does not follow the previous study results (the exponent value decreases with increasing drainage area.) Our exponent value matches the result found w.r.t. debris-flow basins of China for drainage areas less than 100 km2 (Li et al., 2008). Otherwise, the young volcanic basins of Tahiti do not become longer and narrower with increasing basin size (R2=0.1). Besides, there is no correlation between the basin area and the basin convexity (R2=0). This means that there is no statistical change in basin shape with basin size. We present also the drainage area-slope relationship with respect to sediment or transport-limited processes. Key words: Hack’s law, channel morphology, DTM

Identifying the groundwater basin boundaries, using environmental isotopes: a case study

NASA Astrophysics Data System (ADS)

Demiroğlu, Muhterem

2017-06-01

Groundwater, which is renewable under current climatic conditions separately from other natural sources, in fact is a finite resource in terms of quality and fossil groundwater. Researchers have long emphasized the necessity of exploiting, operating, conserving and managing groundwater in an efficient and sustainable manner with an integrated water management approach. The management of groundwater needs reliable information about changes on groundwater quantity and quality. Environmental isotopes are the most important tools to provide this support. No matter which method we use to calculate the groundwater budget and flow equations, we need to determine boundary conditions or the physical boundaries of the domain. The Groundwater divide line or basin boundaries that separate the two adjacent basin recharge areas from each other must be drawn correctly to be successful in defining complex groundwater basin boundary conditions. Environmental isotope data, as well as other methods provide support for determining recharge areas of the aquifers, especially for karst aquifers, residence time and interconnections between aquifer systems. This study demonstrates the use of environmental isotope data to interpret and correct groundwater basin boundaries giving as an example the Yeniçıkrı basin within the main Sakarya basin.

Human impacts on river water quality- comparative research in the catchment areas of the Tone River and the Mur River-

NASA Astrophysics Data System (ADS)

Kogure, K.

2013-12-01

Human activities in river basin affect river water quality as water discharges into river with pollutant after we use it. By detecting pollutants source, pathway, and influential factor of human activities, it will be possible to consider proper river basin management. In this study, material flow analysis was done first and then nutrient emission modeling by MONERIS was conducted. So as to clarify land use contribution and climate condition, comparison of Japanese and European river basin area has been made. The model MONERIS (MOdelling Nutrient Emissions in RIver Systems; Behrendt et al., 2000) was applied to estimate the nutrient emissions in the Danube river basin by point sources and various diffuse pathways. Work for the Mur River Basin in Austria was already carried out by the Institute of Water Quality, Resources and Waste Management at the Vienna University of Technology. This study treats data collection, modelling for the Tone River in Japan, and comparative analysis for these two river basins. The estimation of the nutrient emissions was carried out for 11 different sub catchment areas covering the Tone River Basin for the time period 2000 to 2006. TN emissions into the Tone river basin were 51 kt/y. 67% was via ground water and dominant for all sub catchments. Urban area was also important emission pathway. Human effect is observed in urban structure and agricultural activity. Water supply and sewer system make urban water cycle with pipeline structure. Excess evapotranspiration in arable land is also influential in water cycle. As share of arable land is 37% and there provides agricultural products, it is thought that N emission from agricultural activity is main pollution source. Assumption case of 10% N surplus was simulated and the result was 99% identical to the actual. Even though N surplus reduction does not show drastic impact on N emission, it is of importance to reduce excess of fertilization and to encourage effective agricultural activity. Population rate of waste water treatment is 67 % in the total catchment area. Assumption case of 100% WWT was simulated and the result suggests that connection to public sewer system with WWTP is effective potential measure. TN emission in the Tone is higher than it in the Mur. Emission per capita is almost same level for both basin areas. Though the personal pollution stresses same as European basin area, the basin has huge population and activities to support their daily life. Agricultural activity and urban structure have great impacts on N emission and on the river water quality. Possible remedy for river pollution is construction of sewer system with waste water treatment. Agricultural activity is potential betterment factor. Comparison of Mur, Tone and assumption cases

Hydrological effects of cropland and climatic changes in arid and semi-arid river basins: A case study from the Yellow River basin, China

NASA Astrophysics Data System (ADS)

Li, Huazhen; Zhang, Qiang; Singh, Vijay P.; Shi, Peijun; Sun, Peng

2017-06-01

The Yellow River basin is a typical semi-arid river basin in northern China. Serious water shortages have negative impacts on regional socioeconomic development. Recent years have witnessed changes in streamflow processes due to increasing human activities, such as agricultural activities and construction of dams and water reservoirs, and climatic changes, e.g. precipitation and temperature. This study attempts to investigate factors potentially driving changes in different streamflow components defined by different quantiles. The data used were daily streamflow data for the 1959-2005 period from 5 hydrological stations, daily precipitation and temperature data from 77 meteorological stations and data pertaining to cropland and large reservoirs. Results indicate a general decrease in streamflow across the Yellow River basin. Moreover significant decreasing streamflow has been observed in the middle and lower Yellow River basin with change points during the mid-1980s till the mid-1990s. The changes of cropland affect the streamflow components and also the cumulative effects on streamflow variations. Recent years have witnessed moderate cropland variations which result in moderate streamflow changes. Further, precipitation also plays a critical role in changes of streamflow components and human activities, i.e. cropland changes, temperature changes and building of water reservoirs, tend to have increasing impacts on hydrological processes across the Yellow River basin. This study provides a theoretical framework for the study of the hydrological effects of human activities and climatic changes on basins over the globe.

Assessment of the water supply:demand ratios in a Mediterranean basin under different global change scenarios and mitigation alternatives.

PubMed

Boithias, Laurie; Acuña, Vicenç; Vergoñós, Laura; Ziv, Guy; Marcé, Rafael; Sabater, Sergi

2014-02-01

Spatial differences in the supply and demand of ecosystem services such as water provisioning often imply that the demand for ecosystem services cannot be fulfilled at the local scale, but it can be fulfilled at larger scales (regional, continental). Differences in the supply:demand (S:D) ratio for a given service result in different values, and these differences might be assessed with monetary or non-monetary metrics. Water scarcity occurs where and when water resources are not enough to meet all the demands, and this affects equally the service of water provisioning and the ecosystem needs. In this study we assess the value of water in a Mediterranean basin under different global change (i.e. both climate and anthropogenic changes) and mitigation scenarios, with a non-monetary metric: the S:D ratio. We computed water balances across the Ebro basin (North-East Spain) with the spatially explicit InVEST model. We highlight the spatial and temporal mismatches existing across a single hydrological basin regarding water provisioning and its consumption, considering or not, the environmental demand (environmental flow). The study shows that water scarcity is commonly a local issue (sub-basin to region), but that all demands are met at the largest considered spatial scale (basin). This was not the case in the worst-case scenario (increasing demands and decreasing supply), as the S:D ratio at the basin scale was near 1, indicating that serious problems of water scarcity might occur in the near future even at the basin scale. The analysis of possible mitigation scenarios reveals that the impact of global change may be counteracted by the decrease of irrigated areas. Furthermore, the comparison between a non-monetary (S:D ratio) and a monetary (water price) valuation metrics reveals that the S:D ratio provides similar values and might be therefore used as a spatially explicit metric to valuate the ecosystem service water provisioning. © 2013.

Predicting the ungauged basin: model validation and realism assessment

NASA Astrophysics Data System (ADS)

van Emmerik, Tim; Mulder, Gert; Eilander, Dirk; Piet, Marijn; Savenije, Hubert

2016-04-01

The hydrological decade on Predictions in Ungauged Basins (PUB) [1] led to many new insights in model development, calibration strategies, data acquisition and uncertainty analysis. Due to a limited amount of published studies on genuinely ungauged basins, model validation and realism assessment of model outcome has not been discussed to a great extent. With this study [2] we aim to contribute to the discussion on how one can determine the value and validity of a hydrological model developed for an ungauged basin. As in many cases no local, or even regional, data are available, alternative methods should be applied. Using a PUB case study in a genuinely ungauged basin in southern Cambodia, we give several examples of how one can use different types of soft data to improve model design, calibrate and validate the model, and assess the realism of the model output. A rainfall-runoff model was coupled to an irrigation reservoir, allowing the use of additional and unconventional data. The model was mainly forced with remote sensing data, and local knowledge was used to constrain the parameters. Model realism assessment was done using data from surveys. This resulted in a successful reconstruction of the reservoir dynamics, and revealed the different hydrological characteristics of the two topographical classes. We do not present a generic approach that can be transferred to other ungauged catchments, but we aim to show how clever model design and alternative data acquisition can result in a valuable hydrological model for ungauged catchments. [1] Sivapalan, M., Takeuchi, K., Franks, S., Gupta, V., Karambiri, H., Lakshmi, V., et al. (2003). IAHS decade on predictions in ungauged basins (PUB), 2003-2012: shaping an exciting future for the hydrological sciences. Hydrol. Sci. J. 48, 857-880. doi: 10.1623/hysj.48.6.857.51421 [2] van Emmerik, T., Mulder, G., Eilander, D., Piet, M. and Savenije, H. (2015). Predicting the ungauged basin: model validation and realism assessment. Front. Earth Sci. 3:62. doi: 10.3389/feart.2015.00062

Marginal economic value of streamflow: A case study for the Colorado River Basin

Treesearch

Thomas C. Brown; Benjamin L. Harding; Elizabeth A. Payton

1990-01-01

The marginal economic value of streamflow leaving forested areas in the Colorado River Basin was estimated by determining the impact on water use of a small change in streamflow and then applying economic value estimates to the water use changes. The effect on water use of a change in streamflow was estimated with a network flow model that simulated salinity levels and...

Feedbacks of sedimentation on crustal heat flow - New insights from the Vøring Basin, Norwegian Sea

NASA Astrophysics Data System (ADS)

Theissen, S.; Ruepke, L. H.

2009-04-01

Information on the nature and origin of rift basins is preserved in the presently observed stratigraphy. Basin modeling aims at recovering this information with the goal of quantifying a basin's structural and thermal evolution. Decompaction and backstripping analysis is a classic and still popular approach to basin reconstruction [Steckler and Watts, 1978]. The total and tectonic subsidences, as well as sedimentation rates are calculated by the consecutive decompaction and removal of individual layers. The thermal history has to be computed separately using forward thermal models. An alternative is coupled forward modeling, where the structural and thermal history is computed simultaneously. A key difference between these reconstruction methods is that feedbacks of sedimentation on crustal heat flow are often neglected in backstripping methods. In this work we use the coupled basin modeling approach presented by Rüpke et al. [2008] to quantify some of the feedbacks between sedimentation and heat flow and to explore the differences between both reconstruction approaches in a case study from the Vøring Basin, Norwegian Sea. In a series of synthetic model runs we have reviewed the effects of sedimentation on basement heat flow. These example calculations clearly confirm the well-known blanketing effect of sedimentation and show that it is largest for high sedimentation rates. Recovery of sedimentation rates from the stratigraphy is, however, not straightforward. Decompaction-based methods may systematically underestimate sedimentation rates as sediment thickness is assumed to not change/thin during stretching. We present a new method for computing sedimentation rates based on forward modeling and demonstrate the differences between both methods in terms of rates and thermal feedbacks in a reconstruction of the Vøring basin (Euromargin transect 2). We find that sedimentation rates are systematically higher in forward models and heat flow is clearly depressed during times of high sedimentation. In addition, computed subsidence curves can differ significantly between backtripping and forward modeling methods. This shows that integrated basin modeling is important for improved reconstructions of sedimentary basins and passive margins. Rupke, L. H., et al. (2008), Automated thermotectonostratigraphic basin reconstruction: Viking Graben case study, AAPG Bulletin, 92(3), 309-326. Steckler, M. S., and A. B. Watts (1978), SUBSIDENCE OF ATLANTIC-TYPE CONTINENTAL-MARGIN OFF NEW-YORK, Earth and Planetary Science Letters, 41(1), 1-13.

Sharing water and benefits in transboundary river basins

NASA Astrophysics Data System (ADS)

Arjoon, Diane; Tilmant, Amaury; Herrmann, Markus

2016-06-01

The equitable sharing of benefits in transboundary river basins is necessary to solve disputes among riparian countries and to reach a consensus on basin-wide development and management activities. Benefit-sharing arrangements must be collaboratively developed to be perceived not only as efficient, but also as equitable in order to be considered acceptable to all riparian countries. The current literature mainly describes what is meant by the term benefit sharing in the context of transboundary river basins and discusses this from a conceptual point of view, but falls short of providing practical, institutional arrangements that ensure maximum economic welfare as well as collaboratively developed methods for encouraging the equitable sharing of benefits. In this study, we define an institutional arrangement that distributes welfare in a river basin by maximizing the economic benefits of water use and then sharing these benefits in an equitable manner using a method developed through stakeholder involvement. We describe a methodology in which (i) a hydrological model is used to allocate scarce water resources, in an economically efficient manner, to water users in a transboundary basin, (ii) water users are obliged to pay for water, and (iii) the total of these water charges is equitably redistributed as monetary compensation to users in an amount determined through the application of a sharing method developed by stakeholder input, thus based on a stakeholder vision of fairness, using an axiomatic approach. With the proposed benefit-sharing mechanism, the efficiency-equity trade-off still exists, but the extent of the imbalance is reduced because benefits are maximized and redistributed according to a key that has been collectively agreed upon by the participants. The whole system is overseen by a river basin authority. The methodology is applied to the Eastern Nile River basin as a case study. The described technique not only ensures economic efficiency, but may also lead to more equitable solutions in the sharing of benefits in transboundary river basins because the definition of the sharing rule is not in question, as would be the case if existing methods, such as game theory, were applied, with their inherent definitions of fairness.

Evolution of the Neogene Andean foreland basins of the Southern Pampas and Northern Patagonia (34°-41°S), Argentina

NASA Astrophysics Data System (ADS)

Folguera, Alicia; Zárate, Marcelo; Tedesco, Ana; Dávila, Federico; Ramos, Victor A.

2015-12-01

The Pampas plain (30°-41°S) has historically been considered as a sector that evolved independently from the adjacent Andean ranges. Nevertheless, the study of the Pampas showed that it is reasonable to expect an important influence from the Andes into the extraandean area. The Pampas plain can be divided into two sectors: the northern portion, adjacent to the Pampean Ranges, has been studied by Davila (2005, 2007, 2010). The southern sector (34°-41°S) is the objective of the present work. The study of this area allowed to characterize two separate foreland basins: the Southern Pampa basin and the Northern Patagonian basin. The infill is composed of Late Miocene and Pliocene units, interpreted as distal synorogenic sequences associated with the late Cenozoic Andean uplift at this latitudinal range. These foreland basins have been defined based on facies changes, distinct depositional styles, along with the analysis of sedimentary and isopach maps. The basins geometries are proposed following De Celles and Gilles (1996) taking into account the infill geometry, distribution and grain size. In both cases, these depocenters are located remarkably far away from the Andean tectonics loads. Therefore they cannot be explained with short-wave subsidence patterns. Elastic models explain the tectonic subsidence in the proximal depocenters but fail to replicate the complete distal basins. These characteristics show that dynamic subsidence is controlling the subsidence in the Southern Pampas and Northern Patagonian basins.

Retrospective Case Study in the Raton Basin, Colorado

EPA Pesticide Factsheets

Study site locations in Las Animas and Huerfano Counties were selected in response to ongoing complaints about changes in appearance, odor, and taste associated with drinking water in domestic wells. \

Water Resources Management in the Lerma-Chapala Basin, Mexico: A Case Study

ERIC Educational Resources Information Center

Villamagna, Amy M.; Murphy, Brian R.

2008-01-01

Water resources have become an increasingly important topic of discussion in natural resources and environmental management courses. To address the need for more critical thinking in the classroom and to provide an active learning experience for undergraduate students, we present a case study based on water competition and management in the…

Modeling and Optimization of Recycled Water Systems to Augment Urban Groundwater Recharge through Underutilized Stormwater Spreading Basins.

PubMed

Bradshaw, Jonathan L; Luthy, Richard G

2017-10-17

Infrastructure systems that use stormwater and recycled water to augment groundwater recharge through spreading basins represent cost-effective opportunities to diversify urban water supplies. However, technical questions remain about how these types of managed aquifer recharge systems should be designed; furthermore, existing planning tools are insufficient for performing robust design comparisons. Addressing this need, we present a model for identifying the best-case design and operation schedule for systems that deliver recycled water to underutilized stormwater spreading basins. Resulting systems are optimal with respect to life cycle costs and water deliveries. Through a case study of Los Angeles, California, we illustrate how delivering recycled water to spreading basins could be optimally implemented. Results illustrate trade-offs between centralized and decentralized configurations. For example, while a centralized Hyperion system could deliver more recycled water to the Hansen Spreading Grounds, this system incurs approximately twice the conveyance cost of a decentralized Tillman system (mean of 44% vs 22% of unit life cycle costs). Compared to existing methods, our model allows for more comprehensive and precise analyses of cost, water volume, and energy trade-offs among different design scenarios. This model can inform decisions about spreading basin operation policies and the development of new water supplies.

Alternative methods to determine headwater benefits

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bao, Y.S.; Perlack, R.D.; Sale, M.J.

1997-11-10

In 1992, the Federal Energy Regulatory Commission (FERC) began using a Flow Duration Analysis (FDA) methodology to assess headwater benefits in river basins where use of the Headwater Benefits Energy Gains (HWBEG) model may not result in significant improvements in modeling accuracy. The purpose of this study is to validate the accuracy and appropriateness of the FDA method for determining energy gains in less complex basins. This report presents the results of Oak Ridge National Laboratory`s (ORNL`s) validation of the FDA method. The validation is based on a comparison of energy gains using the FDA method with energy gains calculatedmore » using the MWBEG model. Comparisons of energy gains are made on a daily and monthly basis for a complex river basin (the Alabama River Basin) and a basin that is considered relatively simple hydrologically (the Stanislaus River Basin). In addition to validating the FDA method, ORNL was asked to suggest refinements and improvements to the FDA method. Refinements and improvements to the FDA method were carried out using the James River Basin as a test case.« less

Application of MODIS Products to Infer Possible Relationships Between Basin Land Cover and Coastal Waters Turbidity Using the Magdalena River, Colombia, as a Case Study

NASA Technical Reports Server (NTRS)

Madrinan, Max Jacobo Moreno; Cordova, Africa Flores; Olivares, Francisco Delgado; Irwin, Dan

2012-01-01

Basin development and consequent change in basin land cover have been often associated with an increased turbidity in coastal waters because of sediment yield and nutrients loading. The later leads to phytoplankton abundance further exacerbating water turbidity. This subsequently affects biological and physical processes in coastal estuaries by interfering with sun light penetration to coral reefs and sea grass, and even affecting public health. Therefore, consistent estimation of land cover changes and turbidity trend lines is crucial to design environmental and restoration management plans, to predict fate of possible pollutants, and to estimate sedimentary fluxes into the ocean. Ground solely methods to estimate land cover change would be unpractical and traditional methods of monitoring in situ water turbidity can be very expensive and time consuming. Accurate monitoring on the status and trends of basin land cover as well as the water quality of the receiving water bodies are required for analysis of relationships between the two variables. Use of remote sensing (RS) technology provides a great benefit for both fields of study, facilitating monitoring of changes in a timely and cost effective manner and covering wide areas with long term measurements. In this study, the Magdalena River basin and fixed geographical locations in the estuarine waters of its delta are used as a case to study the temporal trend lines of both, land cover change and the reflectance of the water turbidity using satellite technology. Land cover data from a combined product between sensors Terra and Aqua (MCD12Q1) from MODIS will be adapted to the conditions in the Magdalena basin to estimate changes in land cover since year 2000 to 2009. Surface reflectance data from a MODIS, Terra (MOD09GQ), band 1, will be used in lieu of in situ water turbidity for the time period between 2000 and present. Results will be compared with available existing data.

BasinVis 1.0: A MATLAB®-based program for sedimentary basin subsidence analysis and visualization

NASA Astrophysics Data System (ADS)

Lee, Eun Young; Novotny, Johannes; Wagreich, Michael

2016-06-01

Stratigraphic and structural mapping is important to understand the internal structure of sedimentary basins. Subsidence analysis provides significant insights for basin evolution. We designed a new software package to process and visualize stratigraphic setting and subsidence evolution of sedimentary basins from well data. BasinVis 1.0 is implemented in MATLAB®, a multi-paradigm numerical computing environment, and employs two numerical methods: interpolation and subsidence analysis. Five different interpolation methods (linear, natural, cubic spline, Kriging, and thin-plate spline) are provided in this program for surface modeling. The subsidence analysis consists of decompaction and backstripping techniques. BasinVis 1.0 incorporates five main processing steps; (1) setup (study area and stratigraphic units), (2) loading well data, (3) stratigraphic setting visualization, (4) subsidence parameter input, and (5) subsidence analysis and visualization. For in-depth analysis, our software provides cross-section and dip-slip fault backstripping tools. The graphical user interface guides users through the workflow and provides tools to analyze and export the results. Interpolation and subsidence results are cached to minimize redundant computations and improve the interactivity of the program. All 2D and 3D visualizations are created by using MATLAB plotting functions, which enables users to fine-tune the results using the full range of available plot options in MATLAB. We demonstrate all functions in a case study of Miocene sediment in the central Vienna Basin.

Tsunami Induced Resonance in Enclosed Basins; Case Study of Haydarpasa Port In Istanbul

NASA Astrophysics Data System (ADS)

Kian, Rozita; Cevdet Yalciner, Ahmet; Zaytsev, Andrey; Aytore, Betul

2015-04-01

Coincidence of the frequency of forcing mechanisms and the natural frequency of free oscillations in the harbors or basins leads to formation of resonance oscillations and additional amplifications in the basins. This phenomenon becomes much more critical when it is caused by a tsunamis. In the cases of tsunami induced basin resonances, the wave amplifications may occur with more and unexpected damages. The harbor resilience against the marine hazards is important for the performance and success of recovery operations. Classifying the tsunami effects on the ports and harbors and on their functions is the main concern of this study. There are two types of impacts; direct impacts including structural damages due to strong currents, high water elevation and indirect ones because of basin resonance expose to seiche oscillations. The sea of Marmara has experienced numerous (more than 30) tsunamis in history where a highly populated metropolitan city Istanbul is located at North coast of Maramara sea. There are numerous ports and harbors located at Istanbul Coast. Haydarpasa port (41.0033 N, 29.0139 E) in Istanbul coast near Marmara sea, as a case study is selected to test its resilience under tsunami attack by numerical experiments. There are two breakwaters in Haydarpasa port with total length of three kilometers and the shape of basins are regular. Applying numerical model (NAMI DANCE) which solves nonlinear form of shallow water equations, the resonance oscillations in Haydarpasa Port is investigated by following the method given in Yalciner and Pelinovsky, (2006). In the applications, high resolution bathymetry and topography are used and an initial impulse is inputted to the study domain in the simulations. The computed time histories of water surface fluctuations at different locations inside the harbor are analyzed by using Fast Fourier Transform technique. The frequencies where the peaks of spectrum curves indicates the amplification of waves in the respective gauge location. Therefore these frequencies are the natural frequencies of the Haydarpasa port. The peak points in the spectrum curves are selected as the the resonance frequencies of the Haydarpasa port. Furthermore the coincidence of these frequencies with the frequency of waves of extreme events are discussed and consequent amplification in the Harbor and their effects on harbor operations are discussed.

Marginal Economic Value of Streamflow: A Case Study for the Colorado River Basin

NASA Astrophysics Data System (ADS)

Brown, Thomas C.; Harding, Benjamin L.; Payton, Elizabeth A.

1990-12-01

The marginal economic value of streamflow leaving forested areas in the Colorado River Basin was estimated by determining the impact on water use of a small change in streamflow and then applying economic value estimates to the water use changes. The effect on water use of a change in streamflow was estimated with a network flow model that simulated salinity levels and the routing of flow to consumptive uses and hydroelectric dams throughout the Basin. The results show that, under current water management institutions, the marginal value of streamflow in the Colorado River Basin is largely determined by nonconsumptive water uses, principally energy production, rather than by consumptive agricultural or municipal uses. The analysis demonstrates the importance of a systems framework in estimating the marginal value of streamflow.

AQUATOOL, a generalized decision-support system for water-resources planning and operational management

NASA Astrophysics Data System (ADS)

Andreu, J.; Capilla, J.; Sanchís, E.

1996-04-01

This paper describes a generic decision-support system (DSS) which was originally designed for the planning stage of dicision-making associated with complex river basins. Subsequently, it was expanded to incorporate modules relating to the operational stage of decision-making. Computer-assisted design modules allow any complex water-resource system to be represented in graphical form, giving access to geographically referenced databases and knowledge bases. The modelling capability includes basin simulation and optimization modules, an aquifer flow modelling module and two modules for risk assessment. The Segura and Tagus river basins have been used as case studies in the development and validation phases. The value of this DSS is demonstrated by the fact that both River Basin Agencies currently use a version for the efficient management of their water resources.

Unknown primary Merkel cell carcinoma: 23 new cases and a review.

PubMed

Tarantola, Tina I; Vallow, Laura A; Halyard, Michele Y; Weenig, Roger H; Warschaw, Karen E; Weaver, Amy L; Roenigk, Randall K; Brewer, Jerry D; Otley, Clark C

2013-03-01

Knowledge is limited regarding unknown primary Merkel cell carcinoma (UPMCC). We sought to document the characteristics and behavior of UPMCC, and determine the most appropriate treatment. A multicenter, retrospective, consecutive study reviewing patients given a diagnosis of UPMCC between 1981 and 2008 was completed. In addition, a literature review of cases of UPMCC was performed. In all, 23 patients with UPMCC are described and 34 cases from previous reports are compiled. Among the 23 new cases of UPMCC, the average age at diagnosis was 66.0 years; the majority of patients were male (87%) and Caucasian (100% of those reported). One patient was immunosuppressed, and 39% had a history of other cancer. After the initial biopsy, 16 patients had further evaluation of the involved lymph node basin. Half of these had additional positive nodes (8 of 16). The majority of patients had lymph node basin involvement only (78%), whereas 22% had lymph node basin and distant metastasis. The most common lymph node basin involved was inguinal. The median size of the involved lymph node at diagnosis was 5.0 cm. At 2 years, the overall survival of stage IIIB UPMCC was significantly improved versus stage IIIB known primary Merkel cell carcinoma (MCC): 76.9% to 36.4%. Limited number of cases and retrospective review are limitations. Our data demonstrate improved overall survival in patients with stage IIIB UPMCC versus those with stage IIIB known primary MCC. Because of the unpredictable natural history of UPMCC, we recommend individualization of care based on the details of each patient's clinical presentation. Copyright © 2012 American Academy of Dermatology, Inc. Published by Mosby, Inc. All rights reserved.

Summary of Carbon Storage Incentives and Potential Legislation: East Sub-Basin Project Task 3.1 Business and Financial Case Study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Trabucchi, Chiara

The CarbonSAFE Illinois – East Sub-Basin project is conducting a pre-feasibility assessment for commercial-scale CO2 geological storage complexes. The project aims to identify sites capable of storing more than 50 million tons of industrially-sourced CO2. To support the business development assessment of the economic viability of potential sites in the East Sub-Basin and explore conditions under which a carbon capture and storage (CCS) project therein might be revenue positive, this document provides a summary of carbon storage incentives and legislation of potential relevance to the project.

Distributed and localized horizontal tectonic deformation as inferred from drainage network geometry and topology: A case study from Lebanon

NASA Astrophysics Data System (ADS)

Goren, Liran; Castelltort, Sébastien; Klinger, Yann

2016-04-01

Partitioning of horizontal deformation between localized and distributed modes in regions of oblique tectonic convergence is, in many cases, hard to quantify. As a case study, we consider the Dead Sea Fault System that changes its orientation across Lebanon and forms a restraining bend. The oblique deformation along the Lebanese restraining bend is characterized by a complex suite of tectonic structures, among which, the Yammouneh fault, is believed to be the main strand that relays deformation from the southern section to the northern section of the Dead Sea Fault System. However, uncertainties regarding slip rates along the Yammouneh fault and strain partitioning in Lebanon still prevail. In the current work we use the geometry and topology of river basins together with numerical modeling to evaluate modes and rates of the horizontal deformation in Mount Lebanon that is associated with the Arabia-Sinai relative plate motion. We focus on river basins that drain Mount Lebanon to the Mediterranean and originate close to the Yammouneh fault. We quantify a systematic counterclockwise rotation of these basins and evaluate drainage area disequilibrium using an application of the χ mapping technique, which aims at estimating the degree of geometrical and topological disequilibrium in river networks. The analysis indicates a systematic spatial pattern whereby tributaries of the rotated basins appear to experience drainage area loss or gain with respect to channel length. A kinematic model that is informed by river basin geometry reveals that since the late Miocene, about a quarter of the relative plate motion parallel to the plate boundary has been distributed along a wide band of deformation to the west of the Yammouneh fault. Taken together with previous, shorter-term estimates, the model indicates little variation of slip rate along the Yammouneh fault since the late Miocene. Kinematic model results are compatible with late Miocene paleomagnetic rotations in western Mount Lebanon. A numerical landscape evolution experiment demonstrates the emergence of a similar χ pattern of drainage area disequilibrium in response to progressive distributed shear deformation of river basins with relatively minor drainage network reorganization.

Modeling and analysis of Soil Erosion processes by the River Basins model: The Case Study of the Krivacki Potok Watershed, Montenegro

NASA Astrophysics Data System (ADS)

Vujacic, Dusko; Barovic, Goran; Mijanovic, Dragica; Spalevic, Velibor; Curovic, Milic; Tanaskovic, Vjekoslav; Djurovic, Nevenka

2016-04-01

The objective of this research was to study soil erosion processes in one of Northern Montenegrin watersheds, the Krivacki Potok Watershed of the Polimlje River Basin, using modeling techniques: the River Basins computer-graphic model, based on the analytical Erosion Potential Method (EPM) of Gavrilovic for calculation of runoff and soil loss. Our findings indicate a low potential of soil erosion risk, with 554 m³ yr-1 of annual sediment yield; an area-specific sediment yield of 180 m³km-2 yr-1. The calculation outcomes were validated for the entire 57 River Basins of Polimlje, through measurements of lake sediment deposition at the Potpec hydropower plant dam. According to our analysis, the Krivacki Potok drainage basin is with the relatively low sediment discharge; according to the erosion type, it is mixed erosion. The value of the Z coefficient was calculated on 0.297, what indicates that the river basin belongs to 4th destruction category (of five). The calculated peak discharge from the river basin was 73 m3s-1 for the incidence of 100 years and there is a possibility for large flood waves to appear in the studied river basin. Using the adequate computer-graphic and analytical modeling tools, we improved the knowledge on the soil erosion processes of the river basins of this part of Montenegro. The computer-graphic River Basins model of Spalevic, which is based on the EPM analytical method of Gavrilovic, is highly recommended for soil erosion modelling in other river basins of the Southeastern Europe. This is because of its reliable detection and appropriate classification of the areas affected by the soil loss caused by soil erosion, at the same time taking into consideration interactions between the various environmental elements such as Physical-Geographical Features, Climate, Geological, Pedological characteristics, including the analysis of Land Use, all calculated at the catchment scale.

Constraining uncertainties in water supply reliability in a tropical data scarce basin

NASA Astrophysics Data System (ADS)

Kaune, Alexander; Werner, Micha; Rodriguez, Erasmo; de Fraiture, Charlotte

2015-04-01

Assessing the water supply reliability in river basins is essential for adequate planning and development of irrigated agriculture and urban water systems. In many cases hydrological models are applied to determine the surface water availability in river basins. However, surface water availability and variability is often not appropriately quantified due to epistemic uncertainties, leading to water supply insecurity. The objective of this research is to determine the water supply reliability in order to support planning and development of irrigated agriculture in a tropical, data scarce environment. The approach proposed uses a simple hydrological model, but explicitly includes model parameter uncertainty. A transboundary river basin in the tropical region of Colombia and Venezuela with an approximately area of 2100 km² was selected as a case study. The Budyko hydrological framework was extended to consider climatological input variability and model parameter uncertainty, and through this the surface water reliability to satisfy the irrigation and urban demand was estimated. This provides a spatial estimate of the water supply reliability across the basin. For the middle basin the reliability was found to be less than 30% for most of the months when the water is extracted from an upstream source. Conversely, the monthly water supply reliability was high (r>98%) in the lower basin irrigation areas when water was withdrawn from a source located further downstream. Including model parameter uncertainty provides a complete estimate of the water supply reliability, but that estimate is influenced by the uncertainty in the model. Reducing the uncertainty in the model through improved data and perhaps improved model structure will improve the estimate of the water supply reliability allowing better planning of irrigated agriculture and dependable water allocation decisions.

Socio-Hydrologic Modeling: Characterizing the Dynamics of Coupled Human-Water Systems Using Natural Science Methods

NASA Astrophysics Data System (ADS)

Sivapalan, M.; Elshafei, Y.; Srinivasan, V.

2014-12-01

A challenging research puzzle in the research on sustainable water management in the Anthropocene is why some societies successfully recover from "ecological destruction" to transition to "successful adaptation" over decadal timescales, while others fail. We present a conceptual modeling framework to understand and characterize these transitions. In this way, we aim to capture the potential drivers of the desired shift towards achieving sustainability of socio-hydrological systems. This is done through a synthesis of detailed socio-hydrological analyses of four river basins in three continents, carried out using different quantitative socio-hydrologic models: Murrumbidgee River Basin in eastern Australia, Lake Toolibin Catchment in Western Australia, Tarim River Basin in Western China and Kissimmee River Basin, in south-east United States. The case studies are analysed using either place-based models designed specifically to mimic observed long-term socio-hydrologic trends, or generic conceptual models with foundations in diverse strands of literature including sustainability science and resilience theory. A comparative analysis of the four case studies reveals a commonality in the building blocks employed to model these socio-hydrologic systems; including water balance, economic, environmental and human-feedback components. Each model reveals varying interpretations of a common organising principle that could explain the shift between productive (socio-economic) and restorative (environmental) forces that was evident in each of these systems observed over a long time frame. The emergent principle is related to the essential drivers of the human feedback component and rests with a general formulation of human well-being, as reflected by both their economic and environmental well-being. It is envisaged that the understanding of the system drivers gained from such a comparative study would enable more targeted water management strategies that can be administered in developing basins to achieve overall sustainability.

Uncertainty dimension and basin entropy in relativistic chaotic scattering

NASA Astrophysics Data System (ADS)

Bernal, Juan D.; Seoane, Jesús M.; Sanjuán, Miguel A. F.

2018-04-01

Chaotic scattering is an important topic in nonlinear dynamics and chaos with applications in several fields in physics and engineering. The study of this phenomenon in relativistic systems has received little attention as compared to the Newtonian case. Here we focus our work on the study of some relevant characteristics of the exit basin topology in the relativistic Hénon-Heiles system: the uncertainty dimension, the Wada property, and the basin entropy. Our main findings for the uncertainty dimension show two different behaviors insofar as we change the relativistic parameter β , in which a crossover behavior is uncovered. This crossover point is related with the disappearance of KAM islands in phase space, which happens for velocity values above the ultrarelativistic limit, v >0.1 c . This result is supported by numerical simulations and by qualitative analysis, which are in good agreement. On the other hand, the computation of the exit basins in the phase space suggests the existence of Wada basins for a range of β <0.625 . We also studied the evolution of the exit basins in a quantitative manner by computing the basin entropy, which shows a maximum value for β ≈0.2 . This last quantity is related to the uncertainty in the prediction of the final fate of the system. Finally, our work is relevant in galactic dynamics, and it also has important implications in other topics in physics such as as in the Störmer problem, among others.

Reduction in dengue cases observed during mass control of Aedes (Stegomyia) in street catch basins in an endemic urban area in Colombia

PubMed Central

Ocampo, Clara B.; Mina, Neila Julieth; Carabalí, Mabel; Alexander, Neal; Osorio, Lyda

2015-01-01

Dengue incidence continues to increase globally and, in the absence of an efficacious vaccine, prevention strategies are limited to vector control. It has been suggested that targeting the most productive breeding sites instead of all water-holding containers could be a cost-effective vector control strategy. We sought to identify and continuously control the most productive Aedes (Stegomyia) breeding site in an endemic urban area in Colombia and followed the subsequent incidence of dengue. In the urban area of Guadalajara de Buga, southwestern Colombia, potential breeding sites inside and outside houses were first characterized, and local personnel trained to assess their productivity based on the pupae/person index. Simultaneously, training and monitoring were implemented to improve the dengue case surveillance system. Entomological data and insecticide resistance studies were used to define the targeted intervention. Then, a quasi-experimental design was used to assess the efficacy of the intervention in terms of the positivity index of the targeted and non- targeted breeding sites, and the impact on dengue cases. Street catch basins (storm drains) were the potential breeding site most frequently found containing Aedes immature stages in the baseline (58.3% of 108). Due to the high resistance to temephos (0% mortality after 24 h), the intervention consisted of monthly application of pyriproxyfen in all the street catch basins (n = 4800). A significant decrease in catch basins positivity for Aedes larvae was observed after each monthly treatment (p < 0.001). Over the intervention period, a reduction in the dengue incidence in Buga was observed (rate ratio 0.19, 95% CI 0.12–0.30, p < 0.0001) after adjusting for autocorrelation and controlling with a neighboring town, Palmira, This study highlights the importance of street catch basins as Aedes breeding sites and suggests that their targeted control could help to decrease dengue transmission in such areas. PMID:24388794

Groundwater quality in the Mojave area, California

USGS Publications Warehouse

Dawson, Barbara J. Milby; Belitz, Kenneth

2012-01-01

Groundwater provides more than 40 percent of California’s drinking water. To protect this vital resource, the State of California created the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The Priority Basin Project of the GAMA Program provides a comprehensive assessment of the State’s groundwater quality and increases public access to groundwater-quality information. Four groundwater basins along the Mojave River make up one of the study areas being evaluated. The Mojave study area is approximately 1,500 square miles (3,885 square kilometers) and includes four contiguous groundwater basins: Upper, Middle, and Lower Mojave River Groundwater Basins, and the El Mirage Valley (California Department of Water Resources, 2003). The Mojave study area has an arid climate, and is part of the Mojave Desert. Average annual rainfall is about 6 inches (15 centimeters). Land use in the study area is approximately 82 percent (%) natural (mostly shrubland), 4% agricultural, and 14% urban. The primary crops are pasture and hay. The largest urban areas are the cities of Victorville, Hesperia, and Apple Valley (2010 populations of 116,000, 90,000 and 69,000, respectively). Groundwater in these basins is used for public and domestic water supply and for irrigation. The main water-bearing units are gravel, sand, silt, and clay derived from surrounding mountains. The primary aquifers in the Mojave study area are defined as those parts of the aquifers corresponding to the perforated intervals of wells listed in the California Department of Public Health database. Public-supply wells in the Mojave study area are completed to depths between 200 and 600 feet (18 to 61 meters), consist of solid casing from the land surface to a depth of 130 to 420 feet (40 to 128 meters), and are screened or perforated below the solid casing. Recharge to the groundwater system is primarily runoff from the mountains to the south, mostly through the Mojave River channel. The primary sources of discharge are pumping wells and evapotranspiration.

Vein mineralizations - archives of paleo-fluid systems in the Thuringian basin (Germany)

NASA Astrophysics Data System (ADS)

Abratis, M.; Brey, M.; Fritsch, S.; Majzlan, J.; Viereck-Götte, L.

2012-04-01

We investigate vein mineralizations within and around the Thuringian basin (Germany) in order to characterize paleo-fluid systems that have been active in the basin. By investigating the composition, temperature, origin, age and evolution of paleo-fluids in the Thuringian basin as a model case, we aim for comprehensive understanding of the character of mineralized fluid systems in sedimentary basins in general and their evolution over geological time scales. Mineralizations along faults are archives for the composition of fluids which intruded the basin and circulated within it millions of years ago. These mineralizations give information on the physical and chemical characteristics of the related fluids as well as on their evolution with time during basin evolution. Mapping of mineralizations in space and time and comparison with the present-day fluid circulation system allows for recognition of the paleo-fluid dynamics and high temperature fluid influx pathways. The chemical characteristics of vein-related mineralizations are proxies for the paleo-fluid sources and their solution load. Methods implied comprise bulk rock analyses (petrography, XRD, XRF, ICP-MS), mineral analyses (EPMA, LA-ICP-MS), fluid inclusion measurements (microthermometry, Raman spectroscopy, ion chromatography) and isotope studies (O, H, C, S, Sr). Vein-related mineralizations within the Mesozoic sediments of the basin occur predominantly along WNW-ESE trending fault systems and comprise mainly carbonates and sulfates. Mineralizations within the basin-confining uplifted Variscan basement rocks and lowermost sedimentary units (Zechstein) show also (Fe-, Cu-, Zn-, As-, Sb-) sulfides, (Fe-, Mn-) oxides, fluorite and barite. The present study is part of INFLUINS, a BMBF-funded project bundle which is dedicated to comprehensive description and understanding of the fluid systems within the Thuringian basin in time and space.

Flood risk analysis and adaptive strategy in context of uncertainties: a case study of Nhieu Loc Thi Nghe Basin, Ho Chi Minh City

NASA Astrophysics Data System (ADS)

Ho, Long-Phi; Chau, Nguyen-Xuan-Quang; Nguyen, Hong-Quan

2013-04-01

The Nhieu Loc - Thi Nghe basin is the most important administrative and business area of Ho Chi Minh City. Due to system complexity of the basin such as the increasing trend of rainfall intensity, (tidal) water level and land subsidence, the simulation of hydrological, hydraulic variables for flooding prediction seems rather not adequate in practical projects. The basin is still highly vulnerable despite of multi-million USD investment for urban drainage improvement projects since the last decade. In this paper, an integrated system analysis in both spatial and temporal aspects based on statistical, GIS and modelling approaches has been conducted in order to: (1) Analyse risks before and after projects, (2) Foresee water-related risk under uncertainties of unfavourable driving factors and (3) Develop a sustainable flood risk management strategy for the basin. The results show that given the framework of risk analysis and adaptive strategy, certain urban developing plans in the basin must be carefully revised and/or checked in order to reduce the highly unexpected loss in the future

Integrated modelling of nitrate loads to coastal waters and land rent applied to catchment-scale water management.

PubMed

Refsgaard, A; Jacobsen, T; Jacobsen, B; Ørum, J-E

2007-01-01

The EU Water Framework Directive (WFD) requires an integrated approach to river basin management in order to meet environmental and ecological objectives. This paper presents concepts and full-scale application of an integrated modelling framework. The Ringkoebing Fjord basin is characterized by intensive agricultural production and leakage of nitrate constitute a major pollution problem with respect groundwater aquifers (drinking water), fresh surface water systems (water quality of lakes) and coastal receiving waters (eutrophication). The case study presented illustrates an advanced modelling approach applied in river basin management. Point sources (e.g. sewage treatment plant discharges) and distributed diffuse sources (nitrate leakage) are included to provide a modelling tool capable of simulating pollution transport from source to recipient to analyse the effects of specific, localized basin water management plans. The paper also includes a land rent modelling approach which can be used to choose the most cost-effective measures and the location of these measures. As a forerunner to the use of basin-scale models in WFD basin water management plans this project demonstrates the potential and limitations of comprehensive, integrated modelling tools.

Biomass burning CCN enhance the dynamics of a mesoscale convective system over the La Plata Basin: a numerical approach

NASA Astrophysics Data System (ADS)

Camponogara, Gláuber; Assunção Faus da Silva Dias, Maria; Carrió, Gustavo G.

2018-02-01

High aerosol loadings are discharged into the atmosphere every year by biomass burning in the Amazon and central Brazil during the dry season (July-December). These particles, suspended in the atmosphere, can be carried via a low-level jet toward the La Plata Basin, one of the largest hydrographic basins in the world. Once they reach this region, the aerosols can affect mesoscale convective systems (MCSs), whose frequency is higher during the spring and summer over the basin. The present study is one of the first that seeks to understand the microphysical effects of biomass burning aerosols from the Amazon Basin on mesoscale convective systems over the La Plata Basin. We performed numerical simulations initialized with idealized cloud condensation nuclei (CCN) profiles for an MCS case observed over the La Plata Basin on 21 September 2010. The experiments reveal an important link between CCN number concentration and MCS dynamics, where stronger downdrafts were observed under higher amounts of aerosols, generating more updraft cells in response. Moreover, the simulations show higher amounts of precipitation as the CCN concentration increases. Despite the model's uncertainties and limitations, these results represent an important step toward the understanding of possible impacts on the Amazon biomass burning aerosols over neighboring regions such as the La Plata Basin.

Vulnerability assessment and risk perception: the case of the Arieş River Middle Basin

NASA Astrophysics Data System (ADS)

Ozunu, Al.; Botezan, C.

2012-04-01

Vulnerability assessment is influenced by a number of factors, including risk perception. This paper investigates the vulnerability of people living in the middle basin of the Aries river region, a former mining area, to natural and technologic hazards. The mining industry lead to significant environmental changes, which combined with the social problems caused by its decline (high unemployment rate, low income and old age) raised the level of the vulnerability in the area. This case study is unique, as it includes an evaluation of risk perception and its influence on the social vulnerability and resilience of local communities to disasters. Key words: vulnerability assessment, natural hazards, social vulnerability, risk perception

Chitinozoan zones of the western United States (Great basin), and their comparison with those of the Canning basin, western Australia

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hutter, T.J.

Within the Basin and Ranges of the Great basin of the western US, Ordovician chitinozoans have been recovered in two major lithic facies; the western eugeosynclinal facies and the eastern miogeosynclinal facies. Chitinozoans recovered from these facies range in age from Arenig to Ashgill. Extensive collections from this area make possible the establishment of chitinozoan faunal interval zones from the Ordovician. These zones are compared with those of other investigators for the Canning basin of Western Australia. Selected species of biostratigraphic value include, in chronostratigraphic order, Lagenochitina ovidea Benoit Taugourdeau 1961, Conochitina langei Combaz Peniguel 1972, Conochitina poumoti Combaz Peniguel,more » Desmochitina cf. nodosa Eisenack 1931 , Conochitina moclartii Combaz Peniguel 1972, Conochitina robusta Eisenack 1959, Angochitina capillata Eisenack 1937, Sphaerochitina lepta Jenkins 1970 and Ancyrochitina merga Jenkins 1970. In many cases these zones can be divided into additional subzones using chitinozoans and acritarchs. In all cases, these chitinozoan faunal zones are contrasted with established American graptolite zones, as well as correlated with British standard graptolite zones. The composition of these faunas of the Western US Great basin and Western Australia Canning basin is similar to that from the Marathon region of west Texas, and the Basin Ranges of Arizona and New Mexico.« less

Agro-ecological analysis for the EU water framework directive: an applied case study for the river contract of the Seveso basin (Italy).

PubMed

Bocchi, Stefano; La Rosa, Daniele; Pileri, Paolo

2012-10-01

The innovative approach to the protection and management of water resources at the basin scale introduced by the European Union water framework directive (WFD) requires new scientific tools. WFD implementation also requires the participation of many stakeholders (administrators, farmers and citizens) with the aim of improving the quality of river waters and basin ecosystems through cooperative planning. This approach encompasses different issues, such as agro-ecology, land use planning and water management. This paper presents the results of a methodology suggested for implementing the WFD in the case of the Seveso river contract in Italy, one of the recent WFD applications. The Seveso basin in the Lombardy region has been one of the most rapidly urbanizing areas in Italy over the last 50 years. First, land use changes in the last 50 years are assessed with the use of historical aerial photos. Then, elements of an ecological network along the river corridor are outlined, and different scenarios for enhancing existing ecological connections are assessed using indicators from graph theory. These scenarios were discussed in technical workshops with involved stakeholders of the river contract. The results show a damaged rural landscape, where urbanization processes have decimated the system of linear green features (hedges/rows). Progressive reconnections of some of the identified network nodes may significantly increase the connectivity and circuitry of the study area.

Participatory Planning for the improvement of water management in uncertain conditions: Case study of the Souss-Massa basin in Morocco

NASA Astrophysics Data System (ADS)

Imani, Yasmina; Lahlou, Ouiam; Slimani, Imane; Joyce, Brian

2016-04-01

Due to its geographical location and to the natural features of its climate, Morocco is known as a drought prone and water scarce country. However, the country now faces, in the current context of Climate Change, an increasing and alarming water scarcity due to the combined effects of a strong decline of precipitations and a growing pressure on water resources induced by the economic development and demographic growth. Aware of this pressing issue, Morocco implemented a national water strategy based on the decentralization of water management at the river basin level and the establishment of Integrated Water Resources Management master plans for each basin. Unfortunately, these plans often underestimate the impact of uncertainty and this may lead to inefficient and unsustainable water management strategies. In this context, the aim of this study is to develop an innovative approach for robust decision making in uncertain conditions by coupling the WEAP (Water Evaluation and Planning System) model and the "XLRM" robust decision making framework to support the evaluation of management options and promote long-term sustainable integrated water management strategies at the basin level. The Souss-Massa basin, located in the south-western part of the country was retained as a case study because of its strategic importance but also because it now faces, as a consequence of the irrational use of water resources during the last decades significant water resources management challenges mainly due to the overexploitation of ground water resources, the increased of water demand due to the irrigation development, the urban and industrial growth and the expansion of tourism. Thus, in this study, a three step methodology was developed. First, the WEAP model were developed and calibrated for the Souss-Massa basin. In a second step, a XLRM participatory workshop gathering the basin main stakeholders were organized in order to identify the EXogenous factors (key uncertainties confronting water managers in the basin), the Levers (management actions aiming to improve the system outcomes in the face of the identified uncertainties) and a set of Metrics that can be used to evaluate the ability of specific actions to improve water management outcomes in the basin. In a third step, the R (Responses) component of this XLRM framework were given by the WEAP model that were iteratively used to capture the identified uncertainties, represent the identified strategies and produce the identified metrics. Results of this study focuse on water demand, unmet demand and supply delivered under scenarios of increasing drought periods frequencies, full penetration of drip irrigation and use of desalinated water for irrigation.

A MATLAB®-based program for 3D visualization of stratigraphic setting and subsidence evolution of sedimentary basins: example application to the Vienna Basin

NASA Astrophysics Data System (ADS)

Lee, Eun Young; Novotny, Johannes; Wagreich, Michael

2015-04-01

In recent years, 3D visualization of sedimentary basins has become increasingly popular. Stratigraphic and structural mapping is highly important to understand the internal setting of sedimentary basins. And subsequent subsidence analysis provides significant insights for basin evolution. This study focused on developing a simple and user-friendly program which allows geologists to analyze and model sedimentary basin data. The developed program is aimed at stratigraphic and subsidence modelling of sedimentary basins from wells or stratigraphic profile data. This program is mainly based on two numerical methods; surface interpolation and subsidence analysis. For surface visualization four different interpolation techniques (Linear, Natural, Cubic Spline, and Thin-Plate Spline) are provided in this program. The subsidence analysis consists of decompaction and backstripping techniques. The numerical methods are computed in MATLAB® which is a multi-paradigm numerical computing environment used extensively in academic, research, and industrial fields. This program consists of five main processing steps; 1) setup (study area and stratigraphic units), 2) loading of well data, 3) stratigraphic modelling (depth distribution and isopach plots), 4) subsidence parameter input, and 5) subsidence modelling (subsided depth and subsidence rate plots). The graphical user interface intuitively guides users through all process stages and provides tools to analyse and export the results. Interpolation and subsidence results are cached to minimize redundant computations and improve the interactivity of the program. All 2D and 3D visualizations are created by using MATLAB plotting functions, which enables users to fine-tune the visualization results using the full range of available plot options in MATLAB. All functions of this program are illustrated with a case study of Miocene sediments in the Vienna Basin. The basin is an ideal place to test this program, because sufficient data is available to analyse and model stratigraphic setting and subsidence evolution of the basin. The study area covers approximately 1200 km2 including 110 data points in the central part of the Vienna Basin.

Hydrogeologic data for the northern Rocky Mountains intermontane basins, Montana

USGS Publications Warehouse

Dutton, DeAnn M.; Lawlor, Sean M.; Briar, D.W.; Tresch, R.E.

1995-01-01

The U.S. Geological Survey began a Regional Aquifer- System Analysis of the Northern Rocky Mountains Intermontane Basins of western Montana and central and central and northern Idaho in 1990 to establish a regional framework of information for aquifers in 54 intermontane basins in an area of about 77,500 square miles. Selected hydrogeologic data have been used as part of this analysis to define the hydro- logic systems. Records of 1,376 wells completed in 31 of the 34 intermontane basins in the Montana part of the study area are tabulated in this report. Data consist of location, alttiude of land surface, date well constructed, geologic unit, depth of well, diameter of casing, type of finish, top of open interval, primary use of water, water level, date water level measured, discharge, specific capacity, source of discharge data, type of log available, date water-quality parameters measured, specific conductance, pH, and temperature. Hydrographs for selected wells also are included. Locations of wells and basins are shown on the accompanying plate.

California GAMA Program: Ground-Water Quality Data in the Northern San Joaquin Basin Study Unit, 2005

USGS Publications Warehouse

Bennett, George L.; Belitz, Kenneth; Milby Dawson, Barbara J.

2006-01-01

Growing concern over the closure of public-supply wells because of ground-water contamination has led the State Water Board to establish the Ground-Water Ambient Monitoring and Assessment (GAMA) Program. With the aid of the U.S. Geological Survey (USGS) and Lawrence Livermore National Laboratory, the program goals are to enhance understanding and provide a current assessment of ground-water quality in areas where ground water is an important source of drinking water. The Northern San Joaquin Basin GAMA study unit covers an area of approximately 2,079 square miles (mi2) across four hydrologic study areas in the San Joaquin Valley. The four study areas are the California Department of Water Resources (CADWR) defined Tracy subbasin, the CADWR-defined Eastern San Joaquin subbasin, the CADWR-defined Cosumnes subbasin, and the sedimentologically distinct USGS-defined Uplands study area, which includes portions of both the Cosumnes and Eastern San Joaquin subbasins. Seventy ground-water samples were collected from 64 public-supply, irrigation, domestic, and monitoring wells within the Northern San Joaquin Basin GAMA study unit. Thirty-two of these samples were collected in the Eastern San Joaquin Basin study area, 17 in the Tracy Basin study area, 10 in the Cosumnes Basin study area, and 11 in the Uplands Basin study area. Of the 32 samples collected in the Eastern San Joaquin Basin, 6 were collected using a depth-dependent sampling pump. This pump allows for the collection of samples from discrete depths within the pumping well. Two wells were chosen for depth-dependent sampling and three samples were collected at varying depths within each well. Over 350 water-quality field parameters, chemical constituents, and microbial constituents were analyzed and are reported as concentrations and as detection frequencies, by compound classification as well as for individual constituents, for the Northern San Joaquin Basin study unit as a whole and for each individual study area. Results are presented in a descending order based on detection frequencies (most frequently detected compound listed first), or alphabetically when a detection frequency could not be calculated. Only certain wells were measured for all constituents and water-quality parameters. The results of all of the analyses were compared with U.S. Environmental Protection Agency (USEPA) and California Department of Health Services (CADHS) Maximum Contaminant Levels (MCLs), Secondary Maximum Contaminant Levels (SMCLs), USEPA lifetime health advisories (HA-Ls), the risk-specific dose at a cancer risk level equal to 1 in 100,000 or 10E-5 (RSD5), and CADHS notification levels (NLs). When USEPA and CADHS MCLs are the same, detection levels were compared with the USEPA standard; however, in some cases, the CADHS MCL may be lower. In those cases, the data were compared with the CADHS MCL. Constituents listed by CADHS as 'unregulated chemicals for which monitoring is required' were compared with the CADHS 'detection level for the purposes of reporting' (DLR). DLRs unlike MCLs are not health based standards. Instead, they are levels at which current laboratory detection capabilities allow eighty percent of qualified laboratories to achieve measurements within thirty percent of the true concentration. Twenty-three volatile organic compounds (VOCs) and seven gasoline oxygenates were detected in ground-water samples collected in the Northern San Joaquin Basin GAMA study unit. Additionally, 13 tentatively identified compounds were detected. VOCs were most frequently detected in the Eastern San Joaquin Basin study area and least frequently detected in samples collected in the Cosumnes Basin study area. Dichlorodifluoromethane (CFC-12), a CADHS 'unregulated chemical for which monitoring is required,' was detected in two wells at concentrations greater than the DLR. Trihalomethanes were the most frequently detected class of VOC constituents. Chloroform (trichloromethane) was the m

Study on Law of Groundwater Evolution under Natural and Artificial Forcing with Case study of Haihe River Basin

NASA Astrophysics Data System (ADS)

You, Jinjun; Gan, Hong; Wang, Lin; Bi, Xue; Du, Sisi

2010-05-01

The evolution of groundwater is one of the key problems of water cycle study. It is a result of joint effect of natural condition and human activities, but until now the driving forces of groundwater system evolution were not fully understood due to the complexity of groundwater system structures and the uncertainty of affecting factors. Geology, precipitation and human activity are the main factors affecting the groundwater system evolution and interact each other, but the influence of such three factors on groundwater system are not clarified clearly on a macroscopic scale. The precipitation changes the volume of water recharge and the groundwater pumping effect the discharge of groundwater. Another important factor influencing balance of groundwater storage is the underlaying that affects the renewablility of groundwater. The underlaying is decided mainly by geological attributes but also influenced by human activited. The macroscopic environment of groundwater evolves under the natural and anthropic factors. This paper study the general law of groundwater evolution among the factors based on the case study in Haihe River Basin, a typical area with dramatic groundwater change under natural precipitation attenuation and gradually increase of water suuply. Haihe River Basin is located in north-China, covers an area of 320,041 km2 with over 40% plain areas. The plain area of Haihe Basin is densely populated with many large and medium-sized cities, including metropolis of Beijing and Tianjin, and concentrated irrigated areas, playing important roles in China's economy and food production. It is the unique basin where groundwater occupies majority of total water supply in China. Long-term groundwater over-exploitation causes a series of ecological and environmental problems that threats the sustainable development. In this paper, the historical process of groundwater balance in Haihe Basin is divided into three phases by decrease of rainfall and increase of water pumping. The different problems caused by groundwater shrinkage are summarized. The volume of recharge from natural precipitation and artificial water cycle, natural evaporation and groundwater exploitation are analyzed based on water balance. Through the historical data analysis the changing trend of coefficients of groundwater balance discovers the evolution of groundwater. The general law is concluded with deeper analysis displays the contribution of natural and artificial factors causing deterioration of groundwater balance. A general law of groundwater evolution is put forward to describe the affection of both natural and anthropogenic factors with a relation curve. Considering the water demand of future socio-economic development in Haihe River Basin, the prospective of future vision of groundwater cycle is analyzed by the law of groundwater evolution. Iterated scenario analysis based on comparison of ameliorative function on groundwater balance to point out reasonable control on groundwater exploitation and rational water allocation under the condition of completion of South-to-North Water Transfer Project that could bring more than 7 billion m3 into Haihe River Basin from Yantze River. Finally, the advantages and disadvantages are concluded through the case study and the farther research in this field is pointed out.

Addressing trend-related changes within cumulative effects studies in water resources planning

DOE Office of Scientific and Technical Information (OSTI.GOV)

Canter, L.W., E-mail: envimptr@aol.com; Chawla, M.K.; Swor, C.T.

2014-01-15

Summarized herein are 28 case studies wherein trend-related causative physical, social, or institutional changes were connected to consequential changes in runoff, water quality, and riparian and aquatic ecological features. The reviewed cases were systematically evaluated relative to their identified environmental effects; usage of analytical frameworks, and appropriate models, methods, and technologies; and the attention given to mitigation and/or management of the resultant causative and consequential changes. These changes also represent important considerations in project design and operation, and in cumulative effects studies associated therewith. The cases were grouped into five categories: institutional changes associated with legislation and policies (seven cases);more » physical changes from land use changes in urbanizing watersheds (eight cases); physical changes from land use changes and development projects in watersheds (four cases); physical, institutional, and social changes from land use and related policy changes in river basins (three cases); and multiple changes within a comprehensive study of land use and policy changes in the Willamette River Basin in Oregon (six cases). A tabulation of 110 models, methods and technologies used in the studies is also presented. General observations from this review were that the features were unique for each case; the consequential changes were logically based on the causative changes; the analytical frameworks provided relevant structures for the studies, and the identified methods and technologies were pertinent for addressing both the causative and consequential changes. One key lesson was that the cases provide useful, “real-world” illustrations of the importance of addressing trend-related changes in cumulative effects studies within water resources planning. Accordingly, they could be used as an “initial tool kit” for addressing trend-related changes.« less

Deaths from neoplasms and detection of radionuclides in excised human lungs in the Eordea Basin, Greece.

PubMed

Sichletidis, Lazaros T; Tsiotsios, Ioannis; Gavriilidis, Agapios; Chloros, Diamantis; Konstantinidis, Theodoros; Psarrakos, Kiriakos; Koufogiannis, Dimitrios; Siountas, Anastasios; Filippou, Dimitrios

2003-12-01

Lignite contains various trace-metal natural radioactive contaminants. In the Eordea Basin, the most important lignite field in Greece, the authors conducted a proportional mortality ratio (PMR) study that compared the mortality rates of individuals who lived in the basin vs. a control group who resided in the city of Kilkis, over a 30-yr period. The following information was used in the study: (a) municipal registrations of deaths from neoplasms during the period from 1971 to 2000, and (b) detection of radioactive substances in samples obtained from excised lungs of individuals living in Eordea Basin who suffered from neoplasm. The corresponding registrations of deaths from neoplasm of the inhabitants of Kilkis, a city located outside the Eordea Basin, formed the control group. A diachronic increase of the PMR was detected as a result of neoplasms and, particularly, as a result of lung cancer in Eordea Basin. However, the above ratio did not exceed the corresponding PMR recorded in Kilkis. In 20 lung samples obtained from patients who had lived in Eordea Basin, and in 19 lung samples from patients in Kilkis, the activity of the radionuclides of uranium and thorium radioactive decay series, potassium-40, and cesium-137 was not higher than expected. No statistically significant difference was found between the inhabitants of the 2 regions, thus it was concluded that the increase in respiratory-system neoplasms was likely associated with the high prevalence of smoking among the regions' inhabitants. In future studies, a longer observation period and examination of more cases will be necessary to further investigate a possible association between radionuclides and lung neoplasms in the Eordea Basin.

Flash Floods Simulation using a Physical-Based Hydrological Model at Different Hydroclimatic Regions

NASA Astrophysics Data System (ADS)

Saber, Mohamed; Kamil Yilmaz, Koray

2016-04-01

Currently, flash floods are seriously increasing and affecting many regions over the world. Therefore, this study will focus on two case studies; Wadi Abu Subeira, Egypt as arid environment, and Karpuz basin, Turkey as Mediterranean environment. The main objective of this work is to simulate flash floods at both catchments considering the hydrometeorological differences between them which in turn effect their flash flood behaviors. An integrated methodology incorporating Hydrological River Basin Environmental Assessment Model (Hydro-BEAM) and remote sensing observations was devised. Global Satellite Mapping of Precipitation (GSMAP) were compared with the rain gauge network at the target basins to estimate the bias in an effort to further use it effectively in simulation of flash floods. Based on the preliminary results of flash floods simulation on both basins, we found that runoff behaviors of flash floods are different due to the impacts of climatology, hydrological and topographical conditions. Also, the simulated surface runoff hydrographs are reasonably coincide with the simulated ones. Consequently, some mitigation strategies relying on this study could be introduced to help in reducing the flash floods disasters at different climate regions. This comparison of different climatic basins would be a reasonable implication for the potential impact of climate change on the flash floods frequencies and occurrences.

Engaging expert communities in development of content of Russia’s regional geoportals (case study: “River basins in European Russia” geoportal)

NASA Astrophysics Data System (ADS)

Ermolaeva, P.

2018-01-01

The purpose of this study is to attract expert communities’ intellectual resources to the process of developing a geoportal entitled "River Basins in European Russia". The results of a survey of experts (n=100) have shown that more than half of respondents had used a variety of geoportals’ data in their professional life. Data on digital relief models, streamflows and landscape maps are of greatest interest. In order to obtain a comprehensive social and ecological analysis of the territory, experts have expressed interest in placing data on population in the basins and its density, the volume of used natural resources, and recreational zones on the designed geoportal. In practical sense, our study can be viewed as a fruitful ground for the development of upward vertical communication (from citizens to the government) and partially horizontal communication among citizens via their engagement in the environmental decision-making process.

Decadal Climate Information Needs of Stakeholders for Decision Support in Water and Agriculture Production Sectors: A Case Study in the Missouri River Basin

NASA Astrophysics Data System (ADS)

Mehta, V. M.; Knutson, C.; Rosenberg, N.

2012-12-01

Many decadal climate prediction efforts have been initiated under the World Climate Research Programme's Coupled Model Intercomparison Project 5. There is considerable ongoing discussion about model deficiencies, initialization techniques, and data requirements, but not much attention is being given to decadal climate information (DCI) needs of stakeholders for decision support. We report the results of exploratory activities undertaken to assess DCI needs in water resources and agriculture sectors, using the Missouri River Basin (the Basin) as a case study. This assessment was achieved through discussions with 120 representative stakeholders. Stakeholders' awareness of decadal dry and wet spells and their societal impacts in the Basin is established; and stakeholders' DCI needs and potential barriers to their use of DCI are enumerated. We find that impacts, including economic impacts, of DCV on water and agricultural production in the Basin are distinctly identifiable and characterizable. Stakeholders have clear notions about their needs for DCI and have offered specific suggestions as to how these might be met. But, while stakeholders are eager to have climate information, including decadal climate outlooks (DCOs), there are many barriers to the use of such information. The first and foremost is that the credibility of DCOs is yet to be established. Secondly, the nature of institutional rules and regulations, laws, and legal precedents that pose obstacles to the use of DCOs must be better understood and means to modify these, where possible, must be sought. For the benefit of climate scientists, these and other stakeholder needs will also be articulated in this talk. We are engaged in a project to assess simulation and hindcast skills of DCV phenomena and their associations with hydro-meteorological variability in the Basin in the HadCM3, GFDL-CM2.1, NCAR CCSM4, and MIROC5 global coupled models participating in the WCRP's CMIP5 project. Results from this project will also be described and compared with stakeholder information needs.

Drainage areas of the Twelvepole Creek basin, West Virginia; Big Sandy River basin, West Virginia; Tug Fork basin, Virginia, Kentucky, West Virginia

USGS Publications Warehouse

Wilson, M.W.

1979-01-01

Drainage areas were determined for 61 basins in the Twelvepole Creek basin, West Virginia; 11 basins of the Big Sandy River Basin, West Virginia; and 210 basins in the Tug Fork basin of Virginia, Kentucky, and West Virginia. Most basins with areas greater than 5 square miles were included. Drainage areas were measured with electronic digitizing equipment, and supplementary measurements were made with a hand planimeter. Stream mileages were determined by measuring, with a graduated plastic strip, distances from the mouth of each stream to the measuring point on that stream. Mileages were reported to the nearest one-hundredth of a mile in all cases. The latitude and longitude of each measuring point was determined with electronic digitizing equipment and is reported to the nearest second. The information is listed in tabular form in downstream order. Measuring points for the basins are located in the tables by intersecting tributaries, by counties, by map quadrangles, or by latitude and longitude. (Woodard-USGS)

How widely applicable is river basin management? An analysis of wastewater management in an arid transboundary case.

PubMed

Dombrowsky, Ines; Almog, Ram; Becker, Nir; Feitelson, Eran; Klawitter, Simone; Lindemann, Stefan; Mutlak, Natalie

2010-05-01

The basin scale has been promoted universally as the optimal management unit that allows for the internalization of all external effects caused by multiple water uses. However, the basin scale has been put forward largely on the basis of experience in temperate zones. Hence whether the basin scale is the best scale for management in other settings remains questionable. To address these questions this paper analyzes the economic viability and the political feasibility of alternative management options in the Kidron/Wadi Nar region. The Kidron/Wadi Nar is a small basin in which wastewater from eastern Jerusalem flows through the desert to the Dead Sea. Various options for managing these wastewater flows were analyzed ex ante on the basis of both a cost benefit and a multi-criteria analysis. The paper finds that due to economies of scale, a pure basin approach is not desirable from a physical and economic perspective. Furthermore, in terms of political feasibility, it seems that the option which prompts the fewest objections from influential stakeholder groups in the two entities under the current asymmetrical political setting is not a basin solution either, but a two plant solution based on an outsourcing arrangement. These findings imply that the river basin management approach can not be considered the best management approach for the arid transboundary case at hand, and hence is not unequivocally universally applicable.

How Widely Applicable is River Basin Management? An Analysis of Wastewater Management in an Arid Transboundary Case

NASA Astrophysics Data System (ADS)

Dombrowsky, Ines; Almog, Ram; Becker, Nir; Feitelson, Eran; Klawitter, Simone; Lindemann, Stefan; Mutlak, Natalie

2010-05-01

The basin scale has been promoted universally as the optimal management unit that allows for the internalization of all external effects caused by multiple water uses. However, the basin scale has been put forward largely on the basis of experience in temperate zones. Hence whether the basin scale is the best scale for management in other settings remains questionable. To address these questions this paper analyzes the economic viability and the political feasibility of alternative management options in the Kidron/Wadi Nar region. The Kidron/Wadi Nar is a small basin in which wastewater from eastern Jerusalem flows through the desert to the Dead Sea. Various options for managing these wastewater flows were analyzed ex ante on the basis of both a cost benefit and a multi-criteria analysis. The paper finds that due to economies of scale, a pure basin approach is not desirable from a physical and economic perspective. Furthermore, in terms of political feasibility, it seems that the option which prompts the fewest objections from influential stakeholder groups in the two entities under the current asymmetrical political setting is not a basin solution either, but a two plant solution based on an outsourcing arrangement. These findings imply that the river basin management approach can not be considered the best management approach for the arid transboundary case at hand, and hence is not unequivocally universally applicable.

Effect of detention basin release rates on flood flows - Application of a model to the Blackberry Creek Watershed in Kane County, Illinois

USGS Publications Warehouse

Soong, David T.; Murphy, Elizabeth A.; Straub, Timothy D.

2009-01-01

The effects of stormwater detention basins with specified release rates are examined on the watershed scale with a Hydrological Simulation Program - FORTRAN (HSPF) continuous-simulation model. Modeling procedures for specifying release rates from detention basins with orifice and weir discharge configurations are discussed in this report. To facilitate future detention modeling as a tool for watershed management, a chart relating watershed impervious area to detention volume is presented. The report also presents a case study of the Blackberry Creek watershed in Kane County, Ill., a rapidly urbanizing area seeking to avoid future flood damages from increased urbanization, to illustrate the effects of various detention basin release rates on flood peaks and volumes and flood frequencies. The case study compares flows simulated with a 1996 land-use HSPF model to those simulated with four different 2020 projected land-use HSPF model scenarios - no detention, and detention basins with release rates of 0.08, 0.10, and 0.12 cubic feet per second per acre (ft3/s-acre), respectively. Results of the simulations for 15 locations, which included the downstream ends of all tributaries and various locations along the main stem, showed that a release rate of 0.10 ft3/s-acre, in general, can maintain postdevelopment 100-year peak-flood discharge at a similar magnitude to that of 1996 land-use conditions. Although the release rate is designed to reduce the 100-year peak flow, reduction of the 2-year peak flow is also achieved for a smaller proportion of the peak. Results also showed that the 0.10 ft3/s-acre release rate was less effective in watersheds with relatively high percentages of preexisting (1996) development than in watersheds with less preexisting development.

Countries at Risk: Heightened Human Security Risk to States With Transboundary Water Resources and Instability

NASA Astrophysics Data System (ADS)

Veilleux, J. C.; Sullivan, G. S.; Paola, C.; Starget, A.; Watson, J. E.; Hwang, Y. J.; Picucci, J. A.; Choi, C. S.

2014-12-01

The Countries at Risk project is a global assessment of countries with transboundary water resources that are at risk for conflict because of high human security instability. Building upon Basins at Risk (BAR) research, our team used updated Transboundary Freshwater Dispute Database georeferenced social and environmental data, quantitative data from global indices, and qualitative data from news media sources. Our assessment considered a combination of analyzing 15 global indices related to water or human security to identify which countries scored as highest risk in each index. From this information, we were able to assess the highest risk countries' human security risk by using a new human security measurement tool, as well as comparing this analysis to the World Bank's Fragile States Index and the experimental Human Security Index. In addition, we identified which countries have the highest number of shared basins, the highest percentage of territory covered by a transboundary basin, and the highest dependency of withdrawal from transboundary waters from outside their country boundaries. By synthesizing these social and environmental data assessments, we identified five countries to analyze as case studies. These five countries are Afghanistan, China, Iraq, Moldova, and Sudan. We created a series of 30 maps to spatial analyze the relationship between the transboundary basins and social and environmental parameters to include population, institutional capacity, and physical geography by country. Finally, we synthesized our spatial analysis, Human Security Key scores, and current events scored by using the BAR scale to determine what aspects and which basins are most at risk with each country in our case studies and how this concerns future global water resources.

Model swapping: A comparative performance signature for the prediction of flow duration curves in ungauged basins

NASA Astrophysics Data System (ADS)

Qamar, Muhammad Uzair; Azmat, Muhammad; Cheema, Muhammad Jehanzeb Masud; Shahid, Muhammad Adnan; Khushnood, Rao Arsalan; Ahmad, Sajjad

2016-10-01

The issue of lack of donor basins for prediction of flow duration curves (FDCs) in ungauged basins (PUB) is an important area of research that is not resolved in the literature. We present a distance based approach to predict FDCs at ungauged basins by quantifying the dissimilarity between FDCs and characteristics data of basins. This enables us to bracket hydrologically similar basins and thus allowing us to estimate FDCs at ungauged basins. Generally, a single regression model is selected to make hydrological estimates at an ungauged basin. Based on established laws and theories of hydrology, we work to devise a method to improve the output of selected model for an ungauged basin by swapping it with another model in case the latter gives better coverage and statistical estimates of the nearest neighbors of an ungauged basin. We report two examples to demonstrate the effectiveness of model swapping. Out of 124 basins used in analysis, 34 basins in example 1 and 41 basins in example 2 fulfill the set criteria of model swapping and subsequently their estimates are improved significantly.

Comparing the basins of attraction for several methods in the circular Sitnikov problem with spheroid primaries

NASA Astrophysics Data System (ADS)

Zotos, Euaggelos E.

2018-06-01

The circular Sitnikov problem, where the two primary bodies are prolate or oblate spheroids, is numerically investigated. In particular, the basins of convergence on the complex plane are revealed by using a large collection of numerical methods of several order. We consider four cases, regarding the value of the oblateness coefficient which determines the nature of the roots (attractors) of the system. For all cases we use the iterative schemes for performing a thorough and systematic classification of the nodes on the complex plane. The distribution of the iterations as well as the probability and their correlations with the corresponding basins of convergence are also discussed. Our numerical computations indicate that most of the iterative schemes provide relatively similar convergence structures on the complex plane. However, there are some numerical methods for which the corresponding basins of attraction are extremely complicated with highly fractal basin boundaries. Moreover, it is proved that the efficiency strongly varies between the numerical methods.

From information to participation and self-organization: Visions for European river basin management.

PubMed

Euler, Johannes; Heldt, Sonja

2018-04-15

The European Union Water Framework Directive (EU WFD, 2000) calls for active inclusion of the public in the governance of waterbodies to enhance the effectiveness and legitimacy of water management schemes across the EU. As complex socio-ecological systems, river basins in western Europe could benefit from further support for inclusive management schemes. This paper makes use of case studies from Germany, England and Spain to explore the potential opportunities and challenges of different participatory management approaches. Grounded in theoretical considerations around participation within ecological management schemes, including Arnstein's Ladder of Participation and commons theories, this work provides an evaluation of each case study based on key indicators, such as inclusivity, representativeness, self-organization, decision-making power, spatial fit and temporal continuity. As investors and the public develop a heightened awareness for long-term sustainability of industrial projects, this analysis supports the suggestion that increased participatory river basin management is both desirable and economically feasible, and should thus be considered a viable option for future projects aiming to move beyond current requirements of the European Union Water Framework Directive. Copyright © 2017. Published by Elsevier B.V.

Basins of distinct asymptotic states in the cyclically competing mobile five species game

NASA Astrophysics Data System (ADS)

Kim, Beomseok; Park, Junpyo

2017-10-01

We study the dynamics of cyclic competing mobile five species on spatially extended systems originated from asymmetric initial populations and investigate the basins for the three possible asymptotic states, coexistence of all species, existences of only two independent species, and the extinction. Through extensive numerical simulations, we find a prosperous dependence on initial conditions for species biodiversity. In particular, for fixed given equal densities of two relevant species, we find that only five basins for the existence of two independent species exist and they are spirally entangled for high mobility. A basin of coexistence is outbreaking when the mobility parameter is decreased through a critical value and surrounded by the other five basins. For fixed given equal densities of two independent species, however, we find that basin structures are not spirally entangled. Further, final states of two independent species are totally different. For all possible considerations, the extinction state is not witnessed which is verified by the survival probability. To provide the validity of basin structures from lattice simulations, we analyze the system in mean-field manners. Consequently, results on macroscopic levels are matched to direct lattice simulations for high mobility regimes. These findings provide a good insight into the fundamental issue of the biodiversity among many species than previous cases.

Bed turbulent kinetic energy boundary conditions for trapping efficiency and spatial distribution of sediments in basins.

PubMed

Isenmann, Gilles; Dufresne, Matthieu; Vazquez, José; Mose, Robert

2017-10-01

The purpose of this study is to develop and validate a numerical tool for evaluating the performance of a settling basin regarding the trapping of suspended matter. The Euler-Lagrange approach was chosen to model the flow and sediment transport. The numerical model developed relies on the open source library OpenFOAM ® , enhanced with new particle/wall interaction conditions to limit sediment deposition in zones with favourable hydrodynamic conditions (shear stress, turbulent kinetic energy). In particular, a new relation is proposed for calculating the turbulent kinetic energy threshold as a function of the properties of each particle (diameter and density). The numerical model is compared to three experimental datasets taken from the literature and collected for scale models of basins. The comparison of the numerical and experimental results permits concluding on the model's capacity to predict the trapping of particles in a settling basin with an absolute error in the region of 5% when the sediment depositions occur over the entire bed. In the case of sediment depositions localised in preferential zones, their distribution is reproduced well by the model and trapping efficiency is evaluated with an absolute error in the region of 10% (excluding cases of particles with very low density).

Wide area lithologic mapping with ASTER thermal infrared data: Case studies for the regions in/around the Pamir Mountains and the Tarim basin

NASA Astrophysics Data System (ADS)

Ninomiya, Yoshiki; Fu, Bihong

2017-07-01

After the authors have proposed the mineralogical indices, e.g., Quartz Index (QI), Carbonate Index (CI), Mafic Index (MI) for ASTER thermal infrared (TIR) data, many articles have been applied the indices for the geological case studies and proved to be robust in extracting geological information at the local scale. The authors also have developed a system for producing the regional map with the indices, which needs mosaicking of many scenes considering the relatively narrow spatial coverage of each ASTER scene. The system executes the procedures very efficiently to find ASTER data covering a wide target area in the vast and expanding ASTER data archive. Then the searched ASTER data are conditioned, prioritized, and the indices are calculated before finally mosaicking the imagery. Here in this paper, we will present two case studies of the regional lithologic and mineralogic mapping of the indices covering very wide regions in and around the Pamir Mountains and the Tarim basin. The characteristic features of the indices related to geology are analysed, interpreted and discussed.

Diagenetic effects of compaction on reservoir properties: The case of early callovian ``Dalle Nacrée'' formation (Paris basin, France)

NASA Astrophysics Data System (ADS)

Nader, Fadi H.; Champenois, France; Barbier, Mickaël; Adelinet, Mathilde; Rosenberg, Elisabeth; Houel, Pascal; Delmas, Jocelyne; Swennen, Rudy

2016-11-01

The impact of compaction diagenesis on reservoir properties is addressed by means of observations made on five boreholes with different burial histories of the Early Callovian ;Dalle Nacrée; Formation in the Paris Basin. Petrographic analyses were carried out in order to investigate the rock-texture, pore space type and volume, micro-fabrics, and cement phases. Based on the acquired data, a chronologically ordered sequence of diagenetic events (paragenesis) for each borehole was reconstructed taking the burial history into account. Point counting and a segmentation algorithm (Matlab) were used to quantify porosity, as well as the amounts of grain constituents and cement phases on scanned images of studied thin sections. In addition, four key samples were analyzed by 3D imaging using microfocus X-ray computer tomography. Basin margin grainstones display a different burial diagenesis when compared to basin centre grainstones and wackestones. The former have been affected by considerable cementation (especially by blocky calcite) prior to effective burial, in contrast to the basin centre lithologies where burial and compaction prevailed with relatively less cementation. Fracturing and bed-parallel stylolitization, observed especially in basinal wackestone facies also invoke higher levels of mechanical and chemical compaction than observed in basin marginal equivalents. Compaction fluids may have migrated at the time of burial from the basin centre towards its margins, affecting hence the reservoir properties of similar rock textures and facies and resulting in cross-basin spatial diagenetic heterogeneities.

Description of piezometers installed in the middle Rio Grande basin area, 1997-99, central New Mexico

USGS Publications Warehouse

Bartolino, J.R.; Rankin, D.R.

2000-01-01

Since 1993, the Santa Fe Group aquifer system in the Middle Rio Grande Basin, and particularly in the Albuquerque area, has been the focus of studies to further define the extent of the most productive parts of the aquifer and to gain a better understanding of how ground- water levels are changing over time. The U.S. Geological Survey, in cooperation with the New Mexico Office of the State Engineer, installed nine piezometers during 1998-99 at five sites in and near the margin of the Middle Rio Grande Basin in central New Mexico. In addition, the New Mexico Office of the State Engineer installed another nine piezometers at three sites during 1997. These piezometers allow for collection of ground-water-level data in areas for which little information is available. Most of the piezometers were constructed of 2.5-inch-diameter flush-joint polyvinyl chloride (PVC) schedule 80 casing with 10-foot stainless steel screens; the shallow piezometer at the Tome site has a 40-foot screen, and the single piezometers at the Dome Road and Phoenix Road sites have steel casing with welded joints and a 10- and a 20-foot screen, respectively. Steel casing with a locking lid covers the uppermost 2 feet of the piezometer casing. Drillers' logs and petrophysical logs were collected from the deepest borehole at each site.

Analysis of key thresholds leading to upstream dependencies in global transboundary water bodies

NASA Astrophysics Data System (ADS)

Munia, Hafsa Ahmed; Guillaume, Joseph; Kummu, Matti; Mirumachi, Naho; Wada, Yoshihide

2017-04-01

Transboundary water bodies supply 60% of global fresh water flow and are home to about 1/3 of the world's population; creating hydrological, social and economic interdependencies between countries. Trade-offs between water users are delimited by certain thresholds, that, when crossed, result in changes in system behavior, often related to undesirable impacts. A wide variety of thresholds are potentially related to water availability and scarcity. Scarcity can occur because of the country's own water use, and that is potentially intensified by upstream water use. In general, increased water scarcity escalates the reliance on shared water resources, which increases interdependencies between riparian states. In this paper the upstream dependencies of global transboundary river basins are examined at the scale of sub-basin areas. We aim to assess how upstream water withdrawals cause changes in the scarcity categories, such that crossing thresholds is interpreted in terms of downstream dependency on upstream water availability. The thresholds are defined for different types of water availability on which a sub-basin relies: - reliable local runoff (available even in a dry year), - less reliable local water (available in the wet year), - reliable dry year inflows from possible upstream area, and - less reliable wet year inflows from upstream. Possible upstream withdrawals reduce available water downstream, influencing the latter two water availabilities. Upstream dependencies have then been categorized by comparing a sub-basin's scarcity category across different water availability types. When population (or water consumption) grows, the sub-basin satisfies its needs using less reliable water. Thus, the factors affecting the type of water availability being used are different not only for each type of dependency category, but also possibly for every sub- basin. Our results show that, in the case of stress (impacts from high use of water), in 104 (12%) sub- basins out of 886 sub-basins are dependent on upstream water, while in the case of shortage (impacts from insufficient water availability per person), 79 (9%) sub-basins out of 886 sub-basins dependent on upstream water. Categorization of the upstream dependency of the sub-basins helps to differentiate between areas where i) there is currently no dependency on upstream water, ii) upstream water withdrawals are sufficiently high that they alter the scarcity and dependency status, and iii) which are always dependent on upstream water regardless of upstream water withdrawals. Our dependency assessment is expected to considerably support the studies and discussions of hydro-political power relations and management practices in transboundary basins.

A Methology for Assessing the Regional Transportation Energy Demands of Different Spatial Residential Development Scenarios: a Case Study for the Upper Housatonic River Basin, Massachusetts

NASA Technical Reports Server (NTRS)

Oski, J. A.; Fabos, J. G.; Gross, M.

1982-01-01

A method is suggested whereby regional landscape planning efforts can be aided by the use of a geographic information system to determine sites for more energy efficient residential and mixed use developments within a study area. The location of land parcels suited for residential and mixed land use developments in the Upper Housatonic River Basin Study Area in Berkshire County, Massachusetts is described as well as the three development options. Significant steps in the procedure are discussed and the computation of the transportation energy requirement is elaborated.

Basin-fill Aquifer Modeling with Terrestrial Gravity: Assessing Static Offsets in Bulk Datasets using MATLAB; Case Study of Bridgeport, CA

NASA Astrophysics Data System (ADS)

Mlawsky, E. T.; Louie, J. N.; Pohll, G.; Carlson, C. W.; Blakely, R. J.

2015-12-01

Understanding the potential availability of water resources in Eastern California aquifers is of critical importance to making water management policy decisions and determining best-use practices for California, as well as for downstream use in Nevada. Hydrologic well log data can provide valuable information on aquifer capacity, but is often proprietarily inaccessible or economically unfeasible to obtain in sufficient quantity. In the case of basin-fill aquifers, it is possible to make estimates of aquifer geometry and volume using geophysical surveys of gravity, constrained by additional geophysical and geological observations. We use terrestrial gravity data to model depth-to-basement about the Bridgeport, CA basin for application in preserving the Walker Lake biome. In constructing the model, we assess several hundred gravity observations, existing and newly collected. We regard these datasets as "bulk," as the data are compiled from multiple sources. Inconsistencies among datasets can result in "static offsets," or artificial bull's-eye contours, within the gradient. Amending suspect offsets requires the attention of the modeler; picking these offsets by hand can be a time-consuming process when modeling large-scale basin features. We develop a MATLAB script for interpolating the residual Bouguer anomaly about the basin using sparse observation points, and leveling offset points with a user-defined sensitivity. The script is also capable of plotting gravity profiles between any two endpoints within the map extent. The resulting anomaly map provides an efficient means of locating and removing static offsets in the data, while also providing a fast visual representation of a bulk dataset. Additionally, we obtain gridded basin gravity models with an open-source alternative to proprietary modeling tools.

Probable flood predictions in ungauged coastal basins of El Salvador

USGS Publications Warehouse

Friedel, M.J.; Smith, M.E.; Chica, A.M.E.; Litke, D.

2008-01-01

A regionalization procedure is presented and used to predict probable flooding in four ungauged coastal river basins of El Salvador: Paz, Jiboa, Grande de San Miguel, and Goascoran. The flood-prediction problem is sequentially solved for two regions: upstream mountains and downstream alluvial plains. In the upstream mountains, a set of rainfall-runoff parameter values and recurrent peak-flow discharge hydrographs are simultaneously estimated for 20 tributary-basin models. Application of dissimilarity equations among tributary basins (soft prior information) permitted development of a parsimonious parameter structure subject to information content in the recurrent peak-flow discharge values derived using regression equations based on measurements recorded outside the ungauged study basins. The estimated joint set of parameter values formed the basis from which probable minimum and maximum peak-flow discharge limits were then estimated revealing that prediction uncertainty increases with basin size. In the downstream alluvial plain, model application of the estimated minimum and maximum peak-flow hydrographs facilitated simulation of probable 100-year flood-flow depths in confined canyons and across unconfined coastal alluvial plains. The regionalization procedure provides a tool for hydrologic risk assessment and flood protection planning that is not restricted to the case presented herein. ?? 2008 ASCE.

[Efficacy of using rivaroxaban for treatment of heat-induced thrombosis after endovenous laser ablation].

PubMed

Fokin, A A; Borsuk, D A; Kazachkov, E L

The study was aimed at assessing efficacy of using rivaroxaban for treatment of endothermal heat-induced thrombosis (EHIT) after endovenous laser ablation (EVLA) of saphenous veins. Our prospective study included a total of 1,326 patients subjected to 1,514 EVLAs. In 1,091 (72.1%) cases the great saphenous vein (GSV) was ablated, in 124 (8.2%) cases the anterior accessory vein (AAV) was treated and in 299 (19.7%) cases the small saphenous vein (SSV) was treated. Heat-induced thrombosis developed in 21 (1.4%) cases: in 19 cases in the basin of the great saphenous vein and in 2 cases in the anterior accessory saphenous vein. No heat-induced thromboses in the basin of the small saphenous vein were observed. In 9 (0.6%) cases there was class 1 EHIT (according to the Kabnick classification), class 2 EHIT was noted in 10 (0.7%) cases and class 3 EHIT was observed in 2 (0.1%) cases. All patients with EHIT were given rivaroxaban: patients with class 1 EHIT received it at a single daily dose of 20 mg, patients with class 2 and 3 EHIT - at a dose of 15 mg twice daily. In one (4.8%) case the drug had to be discontinued on day two due to the development of dyspeptic events. All patients were found to have complete regression of the heat-induced thrombus within 6-25 days. No cases of clinical manifestations of pulmonary artery thromboembolism were observed. A conclusion was drawn that in clinical practice EHIT is an important and insufficiently studied problem. Rivaroxaban may be used as an oral agent for treatment of heat-induced thromboses after EVLA. Further studies are required to examine its efficacy and safety profile.

Methodology to incorporate EIA in land-use ordering -- case study: The Cataniapo River basin, Venezuela

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sebastiani, M.; Llambi, L.D.; Marquez, E.

1998-07-01

In Venezuela, the idea of tiering information between land-use ordering instruments and impact assessment is absent. In this article the authors explore a methodological alternative to bridge the information presented in land-use ordering instruments with the information requirements for impact assessment. The methodology is based on the steps carried out for an environmental impact assessment as well as on those considered to develop land-use ordering instruments. The methodology is applied to the territorial ordering plan and its proposal for the protection zone of the Cataniapo River basin. The purpose of the protection zone is to preserve the water quality andmore » quantity of the river basin for human consumption.« less

Two Case Studies to Quantify Resilience across Food-Energy-Water Systems: the Columbia River Treaty and Adaptation in Yakima River Basin Irrigation Systems

NASA Astrophysics Data System (ADS)

Malek, K.; Adam, J. C.; Richey, A.; Rushi, B. R.; Stockle, C.; Yoder, J.; Barik, M.; Lee, S. Y.; Rajagopalan, K.; Brady, M.; Barber, M. E.; Boll, J.; Padowski, J.

2017-12-01

The U.S. Pacific Northwest (PNW) plays a significant role in meeting agricultural and hydroelectric demands nationwide. Climatic and anthropogenic stressors, however, potentially threaten the productivity, resilience, and environmental health of the region. Our objective is to understand how resilience of each Food-Energy-Water (FEW) sector, and the combined Nexus, respond to exogenous perturbations and the extent to which technological and institutional advances can buffer these perturbations. In the process of taking information from complex integrated models and assessing resilience across FEW sectors, we start with two case studies: 1) Columbia River Treaty (CRT) with Canada that determines how multiple reservoirs in the Columbia River basin (CRB) are operated, and 2) climate change adaptation actions in the Yakima River basin (YRB). We discuss these case studies in terms of the similarities and contrasts related to FEW sectors and management complexities. Both the CRB and YBP systems are highly sensitive to climate change (they are both snowmelt-dominant) and already experience water conflict. The CRT is currently undergoing renegotiation; a new CRT will need to consider a much more comprehensive approach, e.g., treating environmental flows explicitly. The YRB also already experiences significant water conflict and thus the comprehensive Yakima Basin Integrated Plan (YBIP) is being pursued. We apply a new modeling framework that mechanistically captures the interactions between the FEW sectors to quantify the impacts of CRT and YBIP planning (as well as adaptation decisions taken by individuals, e.g., irrigators) on resilience in each sector. Proposed modification to the CRT may relieve impacts to multiple sectors. However, in the YRB, irrigators' actions to adapt to climate change (through investing in more efficient irrigation technology) could reduce downstream water availability for other users. Developing a process to quantify resilience to perturbations, such as climate change, will enable innovative solutions that co-balance benefits, and ultimately increase resilience, across all FEW sectors.

Ordovician chitinozoan zones of Great Basin

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hutter, T.J.

Within the Basin and Range province of the Great Basin of the western US, Ordovician chitinozoans have been recovered in two major lithic facies; the western eugeosynclinal facies and the eastern miogeosynclinal facies. Chitinozoans recovered from these facies range in age from Arenig to Ashgill. Extensive collections from this area make possible the establishment of chitinozoan faunal interval zones from the Ordovician of this area. Selected species of biostratigraphic value include, in chronostratigraphic order, Lagenochitina ovoidea Benoit and Taugourdeau, 1961, Conochitina langei Combaz and Peniguel, 1972, Conochitinia poumoti Combaz and Penique, Desmochitina cf. nodosa Eisenack, 1931, Conochitina maclartii Combaz andmore » Peniguel, 1972, Conochitina robusta Eisenack, 1959, Angochitina capitallata Eisenack, 1937, Sphaerochitina lepta Jenkins. 1970, and Ancyrochitina merga Jenkins, 1970. In many cases, these zones can be divided into additional sub-zones using chitinozoans and acritarchs. In all cases, these chitinozoan faunal zones are contrasted with established American graptolite zones of the area, as well as correlated with British standard graptolite zones. The composition of these faunas of the western US Great Basin is similar to that of the Marathon region of west Texas and the Basin Ranges of Arizona and New Mexico, to which direct comparisons have been made. There also appears to be a great similarity with the microfaunas and microfloras of the Ordovician of the Canning basin of western Australia. The Ordovician chitinozoan faunal interval zones established for the Basin and Range province of the Great Basin of the western US also appear to be applicable to the Marathon region of west Texas and the Basin Ranges of Arizona and New Mexico.« less

Late Neogene sedimentary facies and sequences in the Pannonian Basin, Hungary

USGS Publications Warehouse

Juhasz, E.; Phillips, L.; Muller, P.; Ricketts, B.; Toth-Makk, A.; Lantos, M.; Kovacs, L.O.

1999-01-01

This paper is part of the special publication No.156, The Mediterranean basins: Tertiary extension within the Alpine Orogen. (eds B.Durand, L. Jolivet, F.Horvath and M.Seranne). Detailed sedimentological, facies and numerical cycle analysis, combined with magnetostratigraphy, have been made in a number of boreholes in the Pannonian Basin, in order to study the causes of relative water-level changes and the history of the basin subsidence. Subsidence and infilling of the Pannonian Basin, which was an isolated lake at that time occurred mainly during the Late Miocene and Pliocene. The subsidence history was remarkably different in the individual sub-basins: early thermal subsidence was interrupted in the southern part of the basin, while high sedimentation rate and continuous subsidence was detected in the northeastern sub-basin. Three regional unconformities were detected in the Late Neogene Pannonian Basin fill, which represent 0.5 and 7.5 Ma time spans corresponding to single and composite unconformities. Consequently two main sequences build up the Late Neogene Pannonian Basin fill: a Late Miocene and a Pliocene one. Within the Late Miocene sequence there are smaller sedimentary cycles most probably corresponding to climatically driven relative lake-level changes in the Milankovitch frequency band. Considering the periods, the estimated values for precession and eccentricity in this study (19 and 370 ka) are close to the usually cited ones. In the case of obliquity the calculated period (71 ka) slightly deviates from the generally accepted number. Based on the relative amplitudes of oscillations, precession (sixth order) and obliquity (fifth order) cycles had the most significant impact on the sedimentation. Eccentricity caused cycles (fourth order) are poorly detectable in the sediments. The longer term (third order) cycles had very slight influence on the sedimentation pattern. Progradation, recorded in the Late Miocene sequence, correlates poorly in time within the basin. The dominant controls of this process probably were changes of basin subsidence rate and the very high sedimentation rate. The slow, upward trend of silt and sand bed thickness as well as that of the grain size also reflects the local progradation.

Probabilistic evaluation of the water footprint of a river basin: Accounting method and case study in the Segura River Basin, Spain.

PubMed

Pellicer-Martínez, Francisco; Martínez-Paz, José Miguel

2018-06-15

In the current study a method for the probabilistic accounting of the water footprint (WF) at the river basin level has been proposed and developed. It is based upon the simulation of the anthropised water cycle and combines a hydrological model and a decision support system. The methodology was carried out in the Segura River Basin (SRB) in South-eastern Spain, and four historical scenarios were evaluated (1998-2010-2015-2027). The results indicate that the WF of the river basin reached 5581 Mm 3 /year on average in the base scenario, with a high variability. The green component (3231 Mm 3 /year), mainly generated by rainfed crops (62%), was responsible for the great variability of the WF. The blue WF (1201 Mm 3 /year) was broken down into surface water (56%), renewable groundwater (20%) and non-renewable groundwater (24%), and it showed the generalized overexploitation of aquifers. Regarding the grey component (1150 Mm 3 /year), the study reveals that wastewater, especially phosphates (90%), was the main culprit producing water pollution in surface water bodies. The temporal evolution of the four scenarios highlighted the successfulness of the water treatment plans developed in the river basin, with a sharp decrease in the grey WF, as well as the stability of the WF and its three components in the future. So, the accounting of the three components of the WF in a basin was integrated into the management of water resources, it being possible to predict their evolution, their spatial characterisation and even their assessment in probabilistic terms. Then, the WF was incorporated into the set of indicators that usually is used in water resources management and hydrological planning. Copyright © 2018 Elsevier B.V. All rights reserved.

Reservoir Performance Under Future Climate For Basins With Different Hydrologic Sensitivities

NASA Astrophysics Data System (ADS)

Mateus, M. C.; Tullos, D. D.

2013-12-01

In addition to long-standing uncertainties related to variable inflows and market price of power, reservoir operators face a number of new uncertainties related to hydrologic nonstationarity, changing environmental regulations, and rapidly growing water and energy demands. This study investigates the impact, sensitivity, and uncertainty of changing hydrology on hydrosystem performance across different hydrogeologic settings. We evaluate the performance of reservoirs in the Santiam River basin, including a case study in the North Santiam Basin, with high permeability and extensive groundwater storage, and the South Santiam Basin, with low permeability, little groundwater storage and rapid runoff response. The modeling objective is to address the following study questions: (1) for the two hydrologic regimes, how does the flood management, water supply, and environmental performance of current reservoir operations change under future 2.5, 50 and 97.5 percentile streamflow projections; and (2) how much change in inflow is required to initiate a failure to meet downstream minimum or maximum flows in the future. We couple global climate model results with a rainfall-runoff model and a formal Bayesian uncertainty analysis to simulate future inflow hydrographs as inputs to a reservoir operations model. To evaluate reservoir performance under a changing climate, we calculate reservoir refill reliability, changes in flood frequency, and reservoir time and volumetric reliability of meeting minimum spring and summer flow target. Reservoir performance under future hydrology appears to vary with hydrogeology. We find higher sensitivity to floods for the North Santiam Basin and higher sensitivity to minimum flow targets for the South Santiam Basin. Higher uncertainty is related with basins with a more complex hydrologeology. Results from model simulations contribute to understanding of the reliability and vulnerability of reservoirs to a changing climate.

Orbital evidence for more widespread carbonate-bearing rocks on Mars

NASA Astrophysics Data System (ADS)

Wray, James J.; Murchie, Scott L.; Bishop, Janice L.; Ehlmann, Bethany L.; Milliken, Ralph E.; Wilhelm, Mary Beth; Seelos, Kimberly D.; Chojnacki, Matthew

2016-04-01

Carbonates are key minerals for understanding ancient Martian environments because they are indicators of potentially habitable, neutral-to-alkaline water and may be an important reservoir for paleoatmospheric CO2. Previous remote sensing studies have identified mostly Mg-rich carbonates, both in Martian dust and in a Late Noachian rock unit circumferential to the Isidis basin. Here we report evidence for older Fe- and/or Ca-rich carbonates exposed from the subsurface by impact craters and troughs. These carbonates are found in and around the Huygens basin northwest of Hellas, in western Noachis Terra between the Argyre basin and Valles Marineris, and in other isolated locations spread widely across the planet. In all cases they cooccur with or near phyllosilicates, and in Huygens basin specifically they occupy layered rocks exhumed from up to ~5 km depth. We discuss factors that might explain their observed regional distribution, arguments for why carbonates may be even more widespread in Noachian materials than presently appreciated and what could be gained by targeting these carbonates for further study with future orbital or landed missions to Mars.

Geologic Controls on the Growth of Petroleum Reserves

USGS Publications Warehouse

Fishman, Neil S.; Turner, Christine E.; Peterson, Fred; Dyman, Thaddeus S.; Cook, Troy

2008-01-01

The geologic characteristics of selected siliciclastic (largely sandstone) and carbonate (limestone and dolomite) reservoirs in North America (largely the continental United States) were investigated to improve our understanding of the role of geology in the growth of petroleum reserves. Reservoirs studied were deposited in (1) eolian environments (Jurassic Norphlet Formation of the Gulf Coast and Pennsylvanian-Permian Minnelusa Formation of the Powder River Basin), (2) interconnected fluvial, deltaic, and shallow marine environments (Oligocene Frio Formation of the Gulf Coast and the Pennsylvanian Morrow Formation of the Anadarko and Denver Basins), (3) deeper marine environments (Mississippian Barnett Shale of the Fort Worth Basin and Devonian-Mississippian Bakken Formation of the Williston Basin), (4) marine carbonate environments (Ordovician Ellenburger Group of the Permian Basin and Jurassic Smackover Formation of the Gulf of Mexico Basin), (5) a submarine fan environment (Permian Spraberry Formation of the Midland Basin), and (6) a fluvial environment (Paleocene-Eocene Wasatch Formation of the Uinta-Piceance Basin). The connection between an oil reservoir's production history and geology was also evaluated by studying production histories of wells in disparate reservoir categories and wells in a single formation containing two reservoir categories. This effort was undertaken to determine, in general, if different reservoir production heterogeneities could be quantified on the basis of gross geologic differences. It appears that reserve growth in existing fields is most predictable for those in which reservoir heterogeneity is low and thus production differs little between wells, probably owing to relatively homogeneous fluid flow. In fields in which reservoirs are highly heterogeneous, prediction of future growth from infill drilling is notably more difficult. In any case, success at linking heterogeneity to reserve growth depends on factors in addition to geology, such as engineering and technological advances and political or cultural or economic influences.

Effects of anthropogenic groundwater exploitation on land surface processes: A case study of the Haihe River Basin, Northern China

NASA Astrophysics Data System (ADS)

Xie, Z.; Zou, J.; Qin, P.; Sun, Q.

2014-12-01

In this study, we incorporated a groundwater exploitation scheme into the land surface model CLM3.5 to investigate the effects of the anthropogenic exploitation of groundwater on land surface processes in a river basin. Simulations of the Haihe River Basin in northern China were conducted for the years 1965-2000 using the model. A control simulation without exploitation and three exploitation simulations with different water demands derived from socioeconomic data related to the Basin were conducted. The results showed that groundwater exploitation for human activities resulted in increased wetting and cooling effects at the land surface and reduced groundwater storage. A lowering of the groundwater table, increased upper soil moisture, reduced 2 m air temperature, and enhanced latent heat flux were detected by the end of the simulated period, and the changes at the land surface were related linearly to the water demands. To determine the possible responses of the land surface processes in extreme cases (i.e., in which the exploitation process either continued or ceased), additional hypothetical simulations for the coming 200 years with constant climate forcing were conducted, regardless of changes in climate. The simulations revealed that the local groundwater storage on the plains could not contend with high-intensity exploitation for long if the exploitation process continues at the current rate. Changes attributable to groundwater exploitation reached extreme values and then weakened within decades with the depletion of groundwater resources and the exploitation process will therefore cease. However, if exploitation is stopped completely to allow groundwater to recover, drying and warming effects, such as increased temperature, reduced soil moisture, and reduced total runoff, would occur in the Basin within the early decades of the simulation period. The effects of exploitation will then gradually disappear, and the land surface variables will approach the natural state and stabilize at different rates. Simulations were also conducted for cases in which exploitation either continues or ceases using future climate scenario outputs from a general circulation model. The resulting trends were almost the same as those of the simulations with constant climate forcing.

Fish as a proxy for African paleogeography: results from both extant and fossil taxa and prospects to constrain faunal exchange pathway through time

NASA Astrophysics Data System (ADS)

Otero, Olga; Joordens, Josephine; Dettai, Agnès; Christ, Leemans; Pinton, Aurélie

2016-04-01

We assume that basin boundaries constitute barriers to dispersal for freshwater fish and as a consequence that basin geomorphology and connectivity, and its changes through time, can be reconstructed thanks to fish evolutionary history. Firstly, this primary intuitive hypothesis is supported by patterns of fish distribution in the different basins and sub-basins of modern Africa, at both a specific and a generic level, and in certain cases at a family level. This is illustrated by the fact that hydrographical basin boundaries are reflected in the ichthyological provinces as defined and used by ichthyologists for a long time. Moreover, we show that at a continental scale, the hierarchical fish distribution patterns fit with main geological and climatic events according to their depth in time and amplitude [1]. Secondly, we further tested this hypothesis in several ways: (1) through the phylogeographical study of the catfish genus Synodontis [2], chosen because of its modern distribution and its rich fossil record, and (2) through the examination of the fossil record and systematics of the African lungfish Protopterus [3], of the catfish Calarius and of an extinct acanthomorph fish called Semlikiichthys [4,5]. We were then able to correlate these fish histories with quaternary climate change and with geological events throughout the Tertiary in Africa. Our conclusions are also corroborated by existing fish phylogenies that overlap with our region of interest, and elsewhere. While in the last years an increasing number of molecular phylogenetical studies support correlation between fish evolution and basin history at shallow time scales, our studies (and a few other studies) also demonstrate the relevance of fish evolution to work at deeper time and larger geological scales, depending on the taxon distribution and age. Moreover, we plead for the inclusion of fossils when available. Indeed, for extant taxa they are useful to calibrate molecular clocks but also to reveal ancient distributions. The further we are going back in time the more they will constitute most of or the whole relevant sample. Our results also suggest that information on the (paleo)ecology of the fish provides useful data notably to qualify the aquatic systems that have prevailed at the time of connection between basins. So, changes in basin geomorphology constrain fish evolution, and thus we are able to reconstruct and date these changes thanks to fish evolution studies. Since it is widely agreed that the identification of corridors and barriers is critical to understand faunal exchange, we are convinced that for each case study, we can identify the fish (either fossil or extant) that will provide a relevant "geomorphological model". To validate this approach, our current project aims to identify the exchange corridor that may have intermittently existed between the Chad and Turkana basins during the last 3 million years [6]. These corridors may have constituted possible pathways for interbasinal exchange of large mammals at a key time period of Australopithecine evolution. We will end our presentation with preliminary results concerning phylogeography of the extant catfish Synodontis schall, one of our three model species. [1] Pinton A., Otero O. in progress - How much do fish distribution depend on drainage system history? the case study of continental Africa. [2] Pinton A., Agnèse J.F., Paugy D., Otero O. 2013 - A large-scale phylogeny of Synodontis (Mochokidae, Siluriformes) reveals the influence of geological events on continental diversity during the Cenozoic. Molecular Phylogenetics and Evolution, 66 (2013): 1027-1040. [3] Otero O. 2011 - Current knowledge and new assumptions on the evolutionary history of the African lungfish, Protopterus, based on a review of its fossil record. Fish & Fisheries, 2011(12): 235-255. [4] Otero O., Pinton A., Mackaye H.T., Likius A., Vignaud P., Brunet M. 2009 - Fishes and palaeogeography of the African drainage basins: relationships between Chad and neighbouring basins throughout the Mio-Pliocene. Palaeobiogeography, Palaeoclimatology, Palaeoecology, 274 (2009): 134-139. [5] Argyriou T., Otero O., Pavlakis P., Boaz N.T. 2012 - Description and paleobiogeographical implications of new Semlikiichthys (Teleostei, Perciformes) fish material from the Late Miocene deposits of Sahabi, Libya. Geobios, 45(2012): 429-436. [6] Joordens J (Pi) - Coastal origins? A biogeographical model for mominin evolution and dispersal in Africa between 5 and 2.5 million years ago.

Pore Pressure and Field stress variation from Salt Water Injection; A case Study from Beaver Lodge Field in Williston Basin

NASA Astrophysics Data System (ADS)

Mohammed, R. A.; Khatibi, S.

2017-12-01

One of the major concerns in producing from oil and gas reservoirs in North American Basins is the disposal of high salinity salt water. It is a misconception that Hydro frack triggers Earthquakes, but due to the high salinity and density of water being pumped to the formation that has pore space of the rock already filled, which is not the case in Hydro-frack or Enhanced Oil Recovery in which fracturing fluid is pumped into empty pore space of rocks in depleted reservoirs. A review on the Bakken history showed that the concerns related to induce seismicity has increased over time due to variations in Pore pressure and In-situ stress that have shown steep changes in the region over the time. In this study, we focused on Pore pressure and field Stress variations in lower Cretaceous Inyan Kara and Mississippian Devonian Bakken, Inyan Kara is the major source for class-II salt-water disposal in the basin. Salt-water disposal is the major cause for induced seismicity. A full field study was done on Beaver Lodge Field, which has many salt-water disposal wells Adjacent to Oil and Gas Wells. We analyzed formation properties, stresses, pore-pressure, and fracture gradient profile in the field and. The constructed Mechanical Earth Model (MEM) revealed changes in pore pressure and stresses over time due to saltwater injection. Well drilled in the past were compared to recently drilled wells, which showed much stress variations. Safe mud weight Window of wells near proximity of injection wells was examined which showed many cases of wellbore instabilities. Results of this study will have tremendous impact in studying environmental issues and the future drilling and Fracking operations.

Geology, structure, and statistics of multi-ring basins on Mars

NASA Technical Reports Server (NTRS)

Schultz, Richard A.; Frey, Herbert V.

1990-01-01

Available data on Martian multi-ring basins were compiled and evaluated using the new 1:15 million scale geologic maps of Mars and global topography was revised as base maps. Published center coordinates and ring diameters of Martian basins were plotted by computer and superimposed onto the base maps. In many cases basin centers or ring diameters or both had to be adjusted to achieve a better fit to the revised maps. It was also found that additional basins can explain subcircular topographic lows as well as map patterns of old Noachian materials, volcanic plains units, and channels in the Tharsis region.

Application of artificial neural networks in hydrological modeling: A case study of runoff simulation of a Himalayan glacier basin

NASA Technical Reports Server (NTRS)

Buch, A. M.; Narain, A.; Pandey, P. C.

1994-01-01

The simulation of runoff from a Himalayan Glacier basin using an Artificial Neural Network (ANN) is presented. The performance of the ANN model is found to be superior to the Energy Balance Model and the Multiple Regression model. The RMS Error is used as the figure of merit for judging the performance of the three models, and the RMS Error for the ANN model is the latest of the three models. The ANN is faster in learning and exhibits excellent system generalization characteristics.

A quantitative study on accumulation of age mass around stagnation points in nested flow systems

NASA Astrophysics Data System (ADS)

Jiang, Xiao-Wei; Wan, Li; Ge, Shemin; Cao, Guo-Liang; Hou, Guang-Cai; Hu, Fu-Sheng; Wang, Xu-Sheng; Li, Hailong; Liang, Si-Hai

2012-12-01

The stagnant zones in nested flow systems have been assumed to be critical to accumulation of transported matter, such as metallic ions and hydrocarbons in drainage basins. However, little quantitative research has been devoted to prove this assumption. In this paper, the transport of age mass is used as an example to demonstrate that transported matter could accumulate around stagnation points. The spatial distribution of model age is analyzed in a series of drainage basins of different depths. We found that groundwater age has a local or regional maximum value around each stagnation point, which proves the accumulation of age mass. In basins where local, intermediate and regional flow systems are all well developed, the regional maximum groundwater age occurs at the regional stagnation point below the basin valley. This can be attributed to the long travel distances of regional flow systems as well as stagnancy of the water. However, when local flow systems dominate, the maximum groundwater age in the basin can be located around the local stagnation points due to stagnancy, which are far away from the basin valley. A case study is presented to illustrate groundwater flow and age in the Ordos Plateau, northwestern China. The accumulation of age mass around stagnation points is confirmed by tracer age determined by 14C dating in two boreholes and simulated age near local stagnation points under different dispersivities. The results will help shed light on the relationship between groundwater flow and distributions of groundwater age, hydrochemistry, mineral resources, and hydrocarbons in drainage basins.

A nonparametric multivariate standardized drought index for characterizing socioeconomic drought: A case study in the Heihe River Basin

NASA Astrophysics Data System (ADS)

Huang, Shengzhi; Huang, Qiang; Leng, Guoyong; Liu, Saiyan

2016-11-01

Among various drought types, socioeconomic drought is the least investigated type of droughts. Most existing drought indicators ignore the role of local reservoirs and water demand in coping with climatic extremes. In this study, a Multivariate Standardized Reliability and Resilience Index (MSRRI) combining inflow-demand reliability index (IDR) and water storage resilience index (WSR) was applied to examine the evolution characteristics of the socioeconomic droughts in the Heihe River Basin, the second largest inland river basin in northwestern China. Furthermore, the cross wavelet analysis was adopted to explore the associations between annual MSRRI series and El Niño Southern Oscillation (ENSO)/Atlantic Oscillation (AO). Results indicated that: (1) the developed MSRRI is more sensitive to the onset and termination of socioeconomic droughts than IDR and WSR, owing to its joint distribution function of IDR and WSR, responding to changes in either or both of the indices; (2) the MSRRI series in the Heihe River Basin shows non-significant trends at both monthly and annual scales; (3) both ENSO and AO contribute to the changes in the socioeconomic droughts in the Heihe River Basin, and the impacts of ENSO on the socioeconomic droughts are stronger than those of AO.

The Windy Island Soliton Experiment (WISE): Shallow Water and Basin Experiment Configuration and Preliminary Observations

DTIC Science & Technology

2009-02-19

Virginia 22203-1995 The Windy Island Soliton Experiment (WISE): Shallow Water and Basin Experiment Configuration and Preliminary Observations...case letters) The Windy Island Soliton Experiment (WISE): Shallow water and Basin Experiment Configuration and Preliminary Observations 5. FUNDING...release; distribution is unlimited 12b. DISTRIBUTION CODE 13. ABSTRACT (maximum 200 words) The Windy Islands Soliton Experiment (WISE) was

Coupled SWAT-MODFLOW Model Development for Large Basins

NASA Astrophysics Data System (ADS)

Aliyari, F.; Bailey, R. T.; Tasdighi, A.

2017-12-01

Water management in semi-arid river basins requires allocating water resources between urban, industrial, energy, and agricultural sectors, with the latter competing for necessary irrigation water to sustain crop yield. Competition between these sectors will intensify due to changes in climate and population growth. In this study, the recently developed SWAT-MODFLOW coupled hydrologic model is modified for application in a large managed river basin that provides both surface water and groundwater resources for urban and agricultural areas. Specific modifications include the linkage of groundwater pumping and irrigation practices and code changes to allow for the large number of SWAT hydrologic response units (HRU) required for a large river basin. The model is applied to the South Platte River Basin (SPRB), a 56,980 km2 basin in northeastern Colorado dominated by large urban areas along the front range of the Rocky Mountains and agriculture regions to the east. Irregular seasonal and annual precipitation and 150 years of urban and agricultural water management history in the basin provide an ideal test case for the SWAT-MODFLOW model. SWAT handles land surface and soil zone processes whereas MODFLOW handles groundwater flow and all sources and sinks (pumping, injection, bedrock inflow, canal seepage, recharge areas, groundwater/surface water interaction), with recharge and stream stage provided by SWAT. The model is tested against groundwater levels, deep percolation estimates, and stream discharge. The model will be used to quantify spatial groundwater vulnerability in the basin under scenarios of climate change and population growth.

[Hydrochemical Characteristics and Influencing Factors in Different Geological Background: A Case Study in Darongjiang and Lingqu Basin, Guangxi, China].

PubMed

Sun, Ping-an; Yu, Shi; Mo, Fu-zhen; He, Shi-yi; Lu, Ju-fang; Yuan, Ya-qiong

2016-01-15

The observation and sampling were carried out in May 2013 to April 2014 in a hydrological year for two river basins with different geological background in upstream of Li river basin. The seasonal variations of river water chemistry and its main influencing factors were discussed in this paper. The results showed that the hydrochemistry types of both Darongjiang basin with 9% of carbonates and Lingqu basin with nearly 50% of carbonates in area belonged to Ca-HCO3 type. Ca2+ and HCO3- were the main cations and anions. The main ion concentrations were higher in winter and lower in summer, affected by the change of the flow. Ca2+, Mg2+, HCO3- were mainly sourced from the weathering of carbonates by carbonic acid. The weathering of carbonates by sulfuric acid and the weathering of silicate rocks also had contribution to the river water chemistry. In addition, comparing to the Lingqu basin, the contribution of the weathering of carbonates was much more than the percent of carbonates area, because the carbonate rocks were eroded by the allogenic water. On the other hand, K+, Na+, Cl-, NO3-, SO4(2-) were mainly affected by the atmospheric precipitation and human activities. Comparing to the Darongjiang Basin, the effects of human activities on the changes of K+, Na+, Cl-, NO3-, SO4(2-) were more significant in Lingqu Basin.

The isotopic composition of authigenic chromium in anoxic marine sediments: A case study from the Cariaco Basin

NASA Astrophysics Data System (ADS)

Reinhard, Christopher T.; Planavsky, Noah J.; Wang, Xiangli; Fischer, Woodward W.; Johnson, Thomas M.; Lyons, Timothy W.

2014-12-01

Chromium (Cr) isotopes are an emerging proxy for tracking redox processes at the Earth's surface. However, there has been limited exploration of the Cr isotope record of modern and recent marine sediments. The basic inorganic chemistry of Cr suggests that anoxic marine basins should factor prominently in the global Cr cycle and that sediments deposited within anoxic basins may offer a valuable Cr isotope archive throughout Earth's history. Here, we present δ53Cr data from sediments of the Cariaco Basin, Venezuela-a 'type' environment for large, perennially anoxic basins with a relatively strong hydrological connection to the global oceans. We document a marked positive shift in bulk δ53Cr values following the termination of the Last Glacial Maximum, followed by relative stasis. Based on a suite of independent redox proxies, this transition marks a switch from oxic to persistently anoxic and sulfidic (euxinic) depositional conditions within the basin. We find good agreement between two independent approaches toward estimating the δ53Cr composition of authigenic Cr in euxinic Cariaco Basin sediments and that these estimates are very similar to the δ53Cr composition of modern open Atlantic Ocean seawater. These data, together with considerations of reaction kinetics and mass balance within the Cariaco Basin, are consistent with the hypothesis that anoxic marine settings can serve as a chemical archive of first-order trends in seawater δ53Cr composition. Additionally, the Cariaco Basin data suggest that there has been secular stability in the average δ53Cr value of Atlantic seawater over the last ∼15 kyr.

Realizing 2D magnetotelluric inversion in the case of divergent geoelectric strike directions in the crust and mantle - Case study using synthetic models and real data from the Tajo Basin (Spain)

NASA Astrophysics Data System (ADS)

Schmoldt, J.; Jones, A. G.; Muller, M. R.; Kiyan, D.; Hogg, C.; Rosell, O.

2010-12-01

Two-dimensional (2D) inversions of magnetotelluric (MT) data are presently far more commonly used than three-dimensional (3D) inversions as they still significantly outperform 3D inversions in terms of speed, thus allowing for much better resolution of the subsurface through a larger feasible number of grid cells. The suitability of 2D inversion needs thereby to be tested for cases where the electric resistivity structure of the subsurface is potentially 3D to some extent. One particular case of a 3D subsurface structure consists of lateral interfaces with varying orientations at crustal and mantle depths. Such a case might emerge, for instance, where crustal faulting, originating from present day tectonics, is situated above a mantle where structures are dominated by earlier or current plate tectonic processes. Those plate tectonic processes could comprise continental collision from an oblique direction, or lattice preferred orientation in the lithosphere-asthenosphere transition zone due to an oblique relative motion between lithosphere and asthenosphere. Whereas recovery of crustal structures can usually be achieved in a straightforward manner by confining the modelled frequency range to the crustal depths, deriving mantle structures is more challenging. Different approaches for this case have been investigated here using synthetic model studies as well as inversion of a real MT dataset collected in southern Spain as part of the PICASSO fieldwork campaign. The PICASSO project intends to enhance knowledge about the geological setting of the Alboran Domain beneath the western Mediterranean Sea and its surrounding regions, and through that knowledge to understand processes related to continent-continent collision. The Iberian Peninsula is the focus of the first phase of DIAS’s PICASSO efforts, and comprised a magnetotelluric profile crossing the Tajo Basin and Betics Cordillera. Analyses of MT responses and seismic tomography data indicate varying geologic strike direction with depth and along the profile. Geoelectric strike direction in the Tajo Basin crust is approximately NW-SE, coinciding with the direction of the Iberian Range and Neogene faults, whereas at mantle depths a dominant NNE-SSW direction is determined; the Betics region on the contrary exhibits a highly 3D structure originating from its complex tectonic orogeny. This circumstance motivated separate inversions for crustal and mantle structures of the Tajo Basin, as well as for the Betics region. Inversion results of the Tajo Basin subsurface indicate a relatively conducting upper crust underlain by more resistive structures in the lower crust and mantle. The most noticeable features of the models are the apparent upward extension of an electrical resistive lower crustal layer beneath the centre of the basin and the presence of a resistive mantle region that coincides with an area of low seismic velocity. The later indicates an unusual geological situation since typical causes for decreased seismic velocity, e.g. higher temperature, fluids, and less depleted rock chemistry, are commonly thought to decrease electric resistivity.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Warpinski, N.R.; Branagan, P.T.; Sattler, A.R.

This paper is a case study of the stimulation and testing of tight, lenticular sands in the paludal interval of the Mesaverde group in the Piceance basin at DOE's Multiwell Experiment (MWX) site in Colorado. Topics discussed include geologic data, stress test results, well testing, laboratory core studies, stimulation and stimulation analyses, and postfracture operations.

A Collaborative Effort Between Caribbean States for Tsunami Numerical Modeling: Case Study CaribeWave15

NASA Astrophysics Data System (ADS)

Chacón-Barrantes, Silvia; López-Venegas, Alberto; Sánchez-Escobar, Rónald; Luque-Vergara, Néstor

2018-04-01

Historical records have shown that tsunami have affected the Caribbean region in the past. However infrequent, recent studies have demonstrated that they pose a latent hazard for countries within this basin. The Hazard Assessment Working Group of the ICG/CARIBE-EWS (Intergovernmental Coordination Group of the Early Warning System for Tsunamis and Other Coastal Threats for the Caribbean Sea and Adjacent Regions) of IOC/UNESCO has a modeling subgroup, which seeks to develop a modeling platform to assess the effects of possible tsunami sources within the basin. The CaribeWave tsunami exercise is carried out annually in the Caribbean region to increase awareness and test tsunami preparedness of countries within the basin. In this study we present results of tsunami inundation using the CaribeWave15 exercise scenario for four selected locations within the Caribbean basin (Colombia, Costa Rica, Panamá and Puerto Rico), performed by tsunami modeling researchers from those selected countries. The purpose of this study was to provide the states with additional results for the exercise. The results obtained here were compared to co-seismic deformation and tsunami heights within the basin (energy plots) provided for the exercise to assess the performance of the decision support tools distributed by PTWC (Pacific Tsunami Warning Center), the tsunami service provider for the Caribbean basin. However, comparison of coastal tsunami heights was not possible, due to inconsistencies between the provided fault parameters and the modeling results within the provided exercise products. Still, the modeling performed here allowed to analyze tsunami characteristics at the mentioned states from sources within the North Panamá Deformed Belt. The occurrence of a tsunami in the Caribbean may affect several countries because a great variety of them share coastal zones in this basin. Therefore, collaborative efforts similar to the one presented in this study, particularly between neighboring countries, are critical to assess tsunami hazard and increase preparedness within the countries.

A Collaborative Effort Between Caribbean States for Tsunami Numerical Modeling: Case Study CaribeWave15

NASA Astrophysics Data System (ADS)

Chacón-Barrantes, Silvia; López-Venegas, Alberto; Sánchez-Escobar, Rónald; Luque-Vergara, Néstor

2017-10-01

Historical records have shown that tsunami have affected the Caribbean region in the past. However infrequent, recent studies have demonstrated that they pose a latent hazard for countries within this basin. The Hazard Assessment Working Group of the ICG/CARIBE-EWS (Intergovernmental Coordination Group of the Early Warning System for Tsunamis and Other Coastal Threats for the Caribbean Sea and Adjacent Regions) of IOC/UNESCO has a modeling subgroup, which seeks to develop a modeling platform to assess the effects of possible tsunami sources within the basin. The CaribeWave tsunami exercise is carried out annually in the Caribbean region to increase awareness and test tsunami preparedness of countries within the basin. In this study we present results of tsunami inundation using the CaribeWave15 exercise scenario for four selected locations within the Caribbean basin (Colombia, Costa Rica, Panamá and Puerto Rico), performed by tsunami modeling researchers from those selected countries. The purpose of this study was to provide the states with additional results for the exercise. The results obtained here were compared to co-seismic deformation and tsunami heights within the basin (energy plots) provided for the exercise to assess the performance of the decision support tools distributed by PTWC (Pacific Tsunami Warning Center), the tsunami service provider for the Caribbean basin. However, comparison of coastal tsunami heights was not possible, due to inconsistencies between the provided fault parameters and the modeling results within the provided exercise products. Still, the modeling performed here allowed to analyze tsunami characteristics at the mentioned states from sources within the North Panamá Deformed Belt. The occurrence of a tsunami in the Caribbean may affect several countries because a great variety of them share coastal zones in this basin. Therefore, collaborative efforts similar to the one presented in this study, particularly between neighboring countries, are critical to assess tsunami hazard and increase preparedness within the countries.

Mapping monkeypox transmission risk through time and space in the Congo Basin

USGS Publications Warehouse

Nakazawa, Yoshinori J.; Lash, R. Ryan; Carroll, Darin S.; Damon, Inger K.; Karem, Kevin L.; Reynolds, Mary G.; Osorio, Jorge E.; Rocke, Tonie E.; Malekani, Jean; Muyembe, Jean-Jacques; Formenty, Pierre; Peterson, A. Townsend

2013-01-01

Monkeypox is a major public health concern in the Congo Basin area, with changing patterns of human case occurrences reported in recent years. Whether this trend results from better surveillance and detection methods, reduced proportions of vaccinated vs. non-vaccinated human populations, or changing environmental conditions remains unclear. Our objective is to examine potential correlations between environment and transmission of monkeypox events in the Congo Basin. We created ecological niche models based on human cases reported in the Congo Basin by the World Health Organization at the end of the smallpox eradication campaign, in relation to remotely-sensed Normalized Difference Vegetation Index datasets from the same time period. These models predicted independent spatial subsets of monkeypox occurrences with high confidence; models were then projected onto parallel environmental datasets for the 2000s to create present-day monkeypox suitability maps. Recent trends in human monkeypox infection are associated with broad environmental changes across the Congo Basin. Our results demonstrate that ecological niche models provide useful tools for identification of areas suitable for transmission, even for poorly-known diseases like monkeypox.

Mapping monkeypox transmission risk through time and space in the Congo Basin.

PubMed

Nakazawa, Yoshinori; Lash, R Ryan; Carroll, Darin S; Damon, Inger K; Karem, Kevin L; Reynolds, Mary G; Osorio, Jorge E; Rocke, Tonie E; Malekani, Jean M; Muyembe, Jean-Jacques; Formenty, Pierre; Peterson, A Townsend

2013-01-01

Monkeypox is a major public health concern in the Congo Basin area, with changing patterns of human case occurrences reported in recent years. Whether this trend results from better surveillance and detection methods, reduced proportions of vaccinated vs. non-vaccinated human populations, or changing environmental conditions remains unclear. Our objective is to examine potential correlations between environment and transmission of monkeypox events in the Congo Basin. We created ecological niche models based on human cases reported in the Congo Basin by the World Health Organization at the end of the smallpox eradication campaign, in relation to remotely-sensed Normalized Difference Vegetation Index datasets from the same time period. These models predicted independent spatial subsets of monkeypox occurrences with high confidence; models were then projected onto parallel environmental datasets for the 2000s to create present-day monkeypox suitability maps. Recent trends in human monkeypox infection are associated with broad environmental changes across the Congo Basin. Our results demonstrate that ecological niche models provide useful tools for identification of areas suitable for transmission, even for poorly-known diseases like monkeypox.

Mapping Monkeypox Transmission Risk through Time and Space in the Congo Basin

PubMed Central

Nakazawa, Yoshinori; Lash, R. Ryan; Carroll, Darin S.; Damon, Inger K.; Karem, Kevin L.; Reynolds, Mary G.; Osorio, Jorge E.; Rocke, Tonie E.; Malekani, Jean M.; Muyembe, Jean-Jacques; Formenty, Pierre; Peterson, A. Townsend

2013-01-01

Monkeypox is a major public health concern in the Congo Basin area, with changing patterns of human case occurrences reported in recent years. Whether this trend results from better surveillance and detection methods, reduced proportions of vaccinated vs. non-vaccinated human populations, or changing environmental conditions remains unclear. Our objective is to examine potential correlations between environment and transmission of monkeypox events in the Congo Basin. We created ecological niche models based on human cases reported in the Congo Basin by the World Health Organization at the end of the smallpox eradication campaign, in relation to remotely-sensed Normalized Difference Vegetation Index datasets from the same time period. These models predicted independent spatial subsets of monkeypox occurrences with high confidence; models were then projected onto parallel environmental datasets for the 2000s to create present-day monkeypox suitability maps. Recent trends in human monkeypox infection are associated with broad environmental changes across the Congo Basin. Our results demonstrate that ecological niche models provide useful tools for identification of areas suitable for transmission, even for poorly-known diseases like monkeypox. PMID:24040344

Evaluation of the importance of clay confining units on groundwaterflow in alluvial basins using solute and isotope tracers: the case of Middle San Pedro Basin in southeastern Arizona (USA)

USGS Publications Warehouse

Hopkins, Candice B.; McIntosh, Jennifer C.; Eastoe, Chris; Dickinson, Jesse; Meixner, Thomas

2014-01-01

As groundwater becomes an increasingly important water resource worldwide, it is essential to understand how local geology affects groundwater quality, flowpaths and residence times. This study utilized multiple tracers to improve conceptual and numerical models of groundwater flow in the Middle San Pedro Basin in southeastern Arizona (USA) by determining recharge areas, compartmentalization of water sources, flowpaths and residence times. Ninety-five groundwater and surface-water samples were analyzed for major ion chemistry (water type and Ca/Sr ratios) and stable (18O, 2H, 13C) and radiogenic (3H, 14C) isotopes, and resulting data were used in conjunction with hydrogeologic information (e.g. hydraulic head and hydrostratigraphy). Results show that recent recharge (<60 years) has occurred within mountain systems along the basin margins and in shallow floodplain aquifers adjacent to the San Pedro River. Groundwater in the lower basin fill aquifer (semi confined) was recharged at high elevation in the fractured bedrock and has been extensively modified by water-rock reactions (increasing F and Sr, decreasing 14C) over long timescales (up to 35,000 years BP). Distinct solute and isotope geochemistries between the lower and upper basin fill aquifers show the importance of a clay confining unit on groundwater flow in the basin, which minimizes vertical groundwater movement.

Impact of climate change on runoff in Lake Urmia basin, Iran

NASA Astrophysics Data System (ADS)

Sanikhani, Hadi; Kisi, Ozgur; Amirataee, Babak

2018-04-01

Investigation of the impact of climate change on water resources is very necessary in dry and arid regions. In the first part of this paper, the climate model Long Ashton Research Station Weather Generator (LARS-WG) was used for downscaling climate data including rainfall, solar radiation, and minimum and maximum temperatures. Two different case studies including Aji-Chay and Mahabad-Chay River basins as sub-basins of Lake Urmia in the northwest part of Iran were considered. The results indicated that the LARS-WG successfully downscaled the climatic variables. By application of different emission scenarios (i.e., A1B, A2, and B1), an increasing trend in rainfall and a decreasing trend in temperature were predicted for both the basins over future time periods. In the second part of this paper, gene expression programming (GEP) was applied for simulating runoff of the basins in the future time periods including 2020, 2055, and 2090. The input combination including rainfall, solar radiation, and minimum and maximum temperatures in current and prior time was selected as the best input combination with highest predictive power for runoff prediction. The results showed that the peak discharge will decrease by 50 and 55.9% in 2090 comparing with the baseline period for the Aji-Chay and Mahabad-Chay basins, respectively. The results indicated that the sustainable adaptation strategies are necessary for these basins for protection of water resources in future.

Accounting for rainfall spatial variability in the prediction of flash floods

NASA Astrophysics Data System (ADS)

Saharia, Manabendra; Kirstetter, Pierre-Emmanuel; Gourley, Jonathan J.; Hong, Yang; Vergara, Humberto; Flamig, Zachary L.

2017-04-01

Flash floods are a particularly damaging natural hazard worldwide in terms of both fatalities and property damage. In the United States, the lack of a comprehensive database that catalogues information related to flash flood timing, location, causative rainfall, and basin geomorphology has hindered broad characterization studies. First a representative and long archive of more than 15,000 flooding events during 2002-2011 is used to analyze the spatial and temporal variability of flash floods. We also derive large number of spatially distributed geomorphological and climatological parameters such as basin area, mean annual precipitation, basin slope etc. to identify static basin characteristics that influence flood response. For the same period, the National Severe Storms Laboratory (NSSL) has produced a decadal archive of Multi-Radar/Multi-Sensor (MRMS) radar-only precipitation rates at 1-km spatial resolution with 5-min temporal resolution. This provides an unprecedented opportunity to analyze the impact of event-level precipitation variability on flooding using a big data approach. To analyze the impact of sub-basin scale rainfall spatial variability on flooding, certain indices such as the first and second scaled moment of rainfall, horizontal gap, vertical gap etc. are computed from the MRMS dataset. Finally, flooding characteristics such as rise time, lag time, and peak discharge are linked to derived geomorphologic, climatologic, and rainfall indices to identify basin characteristics that drive flash floods. The database has been subjected to rigorous quality control by accounting for radar beam height and percentage snow in basins. So far studies involving rainfall variability indices have only been performed on a case study basis, and a large scale approach is expected to provide a deeper insight into how sub-basin scale precipitation variability affects flooding. Finally, these findings are validated using the National Weather Service storm reports and a historical flood fatalities database. This analysis framework will serve as a baseline for evaluating distributed hydrologic model simulations such as the Flooded Locations And Simulated Hydrographs Project (FLASH) (http://flash.ou.edu).

Using species-specific paleotemperature equations with foraminifera: A case study in the Southern California Bight

USGS Publications Warehouse

Bemis, B.E.; Spero, H.J.; Thunell, R.C.

2002-01-01

Species-specific paleotemperature equations were used to reconstruct a record of temperature from foraminiferal ??18O values over the last 25 kyr in the Southern California Bight. The equations yield similar temperatures for the ??18O values of Globigerina bulloides and Neogloboquadrina pachyderma. In contrast, applying a single paleotemperature equation to G. bulloides and N. pachyderma ??18O yields different temperatures, which has been used to suggest that these species record the surface-to-thermocline temperature gradient. In Santa Barbara Basin, an isotopically distinct morphotype of G. bulloides dominates during glacial intervals and yields temperatures that appear too cold when using a paleotemperature equation calibrated for the morphotype common today. When a more appropriate paleotemperature equation is used for glacial G. bulloides, we obtain more realistic glacial temperatures. Glacial-interglacial temperature differences (G-I ??T) calculated in the present study indicate significant cooling (??? 8-10??C) throughout the Southern California Bight during the last glacial maximum (LGM). The magnitude of glacial cooling varies from ???8??C near the middle of the Southern California Bight (Tanner Basin and San Nicolas Basin) to ???9??C in the north (Santa Barbara Basin) and ???9.5-10??C in the south (Velero Basin and No Name Basin). Our temperature calculations agree well with previous estimates based on the modern analog technique. In contrast, studies using N. pachyderma coiling ratios, U37k??? indices, and transfer functions esfimate considerably warmer LGM temperatures and smaller G-I ??T. ?? 2002 Elsevier Science B.V. All rights reserved.

Utility of aeromagnetic studies for mapping of potentially active faults in two forearc basins: Puget Sound, Washington, and Cook Inlet, Alaska

USGS Publications Warehouse

Saltus, R.W.; Blakely, R.J.; Haeussler, Peter J.; Wells, R.E.

2005-01-01

High-resolution aeromagnetic surveys over forearc basins can detect faults and folds in weakly magnetized sediments, thus providing geologic constraints on tectonic evolution and improved understanding of seismic hazards in convergent-margin settings. Puget Sound, Washington, and Cook Inlet, Alaska, provide two case histories. In each lowland region, shallow-source magnetic anomalies are related to active folds and/or faults. Mapping these structures is critical for understanding seismic hazards that face the urban regions of Seattle, Washington, and Anchorage, Alaska. Similarities in aeromagnetic anomaly patterns and magnetic stratigraphy between the two regions suggest that we can expect the aeromagnetic method to yield useful structural information that may contribute to earth-hazard and energy resource investigations in other forearc basins.

Parallel Monotonic Basin Hopping for Low Thrust Trajectory Optimization

NASA Technical Reports Server (NTRS)

McCarty, Steven L.; McGuire, Melissa L.

2018-01-01

Monotonic Basin Hopping has been shown to be an effective method of solving low thrust trajectory optimization problems. This paper outlines an extension to the common serial implementation by parallelizing it over any number of available compute cores. The Parallel Monotonic Basin Hopping algorithm described herein is shown to be an effective way to more quickly locate feasible solutions, and improve locally optimal solutions in an automated way without requiring a feasible initial guess. The increased speed achieved through parallelization enables the algorithm to be applied to more complex problems that would otherwise be impractical for a serial implementation. Low thrust cislunar transfers and a hybrid Mars example case demonstrate the effectiveness of the algorithm. Finally, a preliminary scaling study quantifies the expected decrease in solve time compared to a serial implementation.,

Reconstructing the 2015 Flash Flood event of Salgar Colombia, The Case of a Poor Gauged Basin

NASA Astrophysics Data System (ADS)

Velasquez, N.; Zapata, E.; Hoyos Ortiz, C. D.; Velez, J. I.

2017-12-01

Flash floods events associated with severe precipitation events are highly destructive, often resulting in significant human and economic losses. Due to their nature, flash floods trend to occur in medium to small basins located within complex high mountainous regions. In the Colombian Andean region these basins are very common, with the aggravating factor that the vulnerability is considerably high as some important human settlements are located within these basins, frequently occupating flood plains and other flash-flood prone areas. During the dawn of May 18 of 2015 two severe rainfall events generated a flash flood event in the municipality ofSalgar, La Liboriana basin, locatedin the northwestern Colombian Andes, resulting in more than 100 human casualties and significant economic losses. The present work is a reconstruction of the hydrological processes that took place before and during the Liboriana flash flood event, analyzed as a case of poorly gauged basin.The event conditions where recreated based on radar retrievals and a hydrological distributed model, linked with a proposed 1D hydraulic model and simple shallow landslide model. Results suggest that the flash flood event was caused by the occurrence of two successive severe convective events over the same basin, with an important modulation associated with soil characteristics and water storage.Despite of its simplicity, the proposed hydraulic model achieves a good representation of the flooded area during the event, with limitations due to the adopted spatial scale (12.7 meters, from ALOS PALSAR images). Observed landslides were obtained from satellite images; for this case the model simulates skillfully the landslide occurrence regions with small differences in the exact locations.To understand this case, radar data shows to be key due to specific convective cores location and rainfall intensity estimation.In mountainous regions, there exists a significant number of settlements with similar vulnerability and with the same gauging conditions, the use of low-cost modelling strategy could represent a good risk management tool in these regions with low planning capabilities.

GIS based quantitative morphometric analysis and its consequences: a case study from Shanur River Basin, Maharashtra India

NASA Astrophysics Data System (ADS)

Pande, Chaitanya B.; Moharir, Kanak

2017-05-01

A morphometric analysis of Shanur basin has been carried out using geoprocessing techniques in GIS. These techniques are found relevant for the extraction of river basin and its drainage networks. The extracted drainage network was classified according to Strahler's system of classification and it reveals that the terrain exhibits dendritic to sub-dendritic drainage pattern. Hence, from the study, it is concluded that remote sensing data (SRTM-DEM data of 30 m resolution) coupled with geoprocessing techniques prove to be a competent tool used in morphometric analysis and evaluation of linear, slope, areal and relief aspects of morphometric parameters. The combined outcomes have established the topographical and even recent developmental situations in basin. It will also change the setup of the region. It therefore needs to analyze high level parameters of drainage and environment for suitable planning and management of water resource developmental plan and land resource development plan. The Shanur drainage basin is sprawled over an area of 281.33 km2. The slope of the basin varies from 1 to 10 %, and the slope variation is chiefly controlled by the local geology and erosion cycles. The main stream length ratio of the basin is 14.92 indicating that the study area is elongated with moderate relief and steep slopes. The morphometric parameters of the stream have been analyzed and calculated by applying standard methods and techniques viz. Horton (Trans Am Geophys Union 13:350-361, 1945), Miller (A quantitative geomorphologic study of drainage basin characteristics in the clinch mountain area, Virginia and Tennessee Columbia University, Department of Geology, Technical Report, No. 3, Contract N6 ONR 271-300, 1953), and Strahler (Handbook of applied hydrology, McGraw Hill Book Company, New York, 1964). GIS based on analysis of all morphometric parameters and the erosional development of the area by the streams has been progressed well beyond maturity and lithology is an influence in the drainage development. These studies are very useful for planning of rainwater harvesting and watershed management.

Inversion of Magnetic Measurements of the CHAMP Satellite Over the Pannonian Basin

NASA Technical Reports Server (NTRS)

Kis, K. I.; Taylor, P. T.; Wittmann, G.; Toronyi, B.; Puszta, S.

2011-01-01

The Pannonian Basin is a deep intra-continental basin that formed as part of the Alpine orogeny. In order to study the nature of the crustal basement we used the long-wavelength magnetic anomalies acquired by the CHAMP satellite. The anomalies were distributed in a spherical shell, some 107,927 data recorded between January 1 and December 31 of 2008. They covered the Pannonian Basin and its vicinity. These anomaly data were interpolated into a spherical grid of 0.5 x 0.5, at the elevation of 324 km by the Gaussian weight function. The vertical gradient of these total magnetic anomalies was also computed and mapped to the surface of a sphere at 324 km elevation. The former spherical anomaly data at 425 km altitude were downward continued to 324 km. To interpret these data at the elevation of 324 km we used an inversion method. A polygonal prism forward model was used for the inversion. The minimum problem was solved numerically by the Simplex and Simulated annealing methods; a L2 norm in the case of Gaussian distribution parameters and a L1 norm was used in the case of Laplace distribution parameters. We INTERPRET THAT the magnetic anomaly WAS produced by several sources and the effect of the sable magnetization of the exsolution of hemo-ilmenite minerals in the upper crustal metamorphic rocks.

A Study on the Assessment of Multi-Factors Affecting Urban Floods Using Satellite Image: A Case Study in Nakdong Basin, S. Korea

NASA Astrophysics Data System (ADS)

Kwak, Youngjoo; Kondoh, Akihiko

2010-05-01

Floods are also related to the changes in social economic conditions and land use. Recently, floods increased due to rapid urbanization and human activity in the lowland. Therefore, integrated management of total basin system is necessary to get the secure society. Typhoon ‘Rusa’ swept through eastern and southern parts of South Korea in the 2002. This pity experience gave us valuable knowledge that could be used to mitigate the future flood hazards. The purpose of this study is to construct the digital maps of the multi-factors related to urban flood concerning geomorphologic characteristics, land cover, and surface wetness. Parameters particularly consider geomorphologic functional unit, geomorphologic parameters derived from DEM (digital elevation model), and land use. The research area is Nakdong River Basin in S. Korea. As a result of preliminary analysis for Pusan area, the vulnerability map and the flood-prone areas can be extracted by applying spatial analysis on GIS (geographic information system).

Decomposition analysis of water footprint changes in a water-limited river basin: a case study of the Haihe River basin, China

NASA Astrophysics Data System (ADS)

Zhi, Y.; Yang, Z. F.; Yin, X. A.

2014-05-01

Decomposition analysis of water footprint (WF) changes, or assessing the changes in WF and identifying the contributions of factors leading to the changes, is important to water resource management. Instead of focusing on WF from the perspective of administrative regions, we built a framework in which the input-output (IO) model, the structural decomposition analysis (SDA) model and the generating regional IO tables (GRIT) method are combined to implement decomposition analysis for WF in a river basin. This framework is illustrated in the WF in Haihe River basin (HRB) from 2002 to 2007, which is a typical water-limited river basin. It shows that the total WF in the HRB increased from 4.3 × 1010 m3 in 2002 to 5.6 × 1010 m3 in 2007, and the agriculture sector makes the dominant contribution to the increase. Both the WF of domestic products (internal) and the WF of imported products (external) increased, and the proportion of external WF rose from 29.1 to 34.4%. The technological effect was the dominant contributor to offsetting the increase of WF. However, the growth of WF caused by the economic structural effect and the scale effect was greater, so the total WF increased. This study provides insights about water challenges in the HRB and proposes possible strategies for the future, and serves as a reference for WF management and policy-making in other water-limited river basins.

Influence of hydrodynamic features in the transport and fate of hazard contaminants within touristic ports. Case study: Torre a Mare (Italy).

PubMed

Mali, Matilda; Malcangio, Daniela; Dell' Anna, Maria Michela; Damiani, Leonardo; Mastrorilli, Piero

2018-01-01

The environmental quality of Torre a Mare port (Italy) was assessed evaluating on one side, the chemical concentration of nine metals and metalloids within bottom sediments and on the other one, by exploring the impact of hydrodynamic conditions in contaminant's transport within the most polluted basins. The investigated port was selected as case study because it resulted much more polluted than it was expected based on the touristic port activities and related stressors loading on it. In order to determine the origin and fate of contaminants in the port basin, 2D numerical simulations were carried out by MIKE21 software. The hydrodynamic module (HD) based on a rectangular grid was initially used to characterize the flow field into two domains that cover the inner and offshore harbor area. Then, advection-dispersion (AD) and water quality (WQ) modules were coupled in order to simulate the simultaneous processes of transport and dispersion of hypothetical pollutant sources. The dissolved/suspended sediment particulates (DSS) were selected as contaminant tracers. The comparative analysis between simulation responses and the real metal contaminant distribution showed high agreement, suggesting that contaminants mainly come from outside port and tend to accumulate in the inner basin. In fact, hydrodynamic circulations cause inflowing streams toward the harbor entrance and the particular port morphology hampers the exit of fine sediments from the inner basin, enhancing thus the accumulation of sediment-associated contaminants within the port area. The study confirms that the quality of touristic port areas strongly depends on both pollution sources located within and outside the port domain and it is controlled mainly by the hydrodynamic-driven processes.

The Impact of Land Abandonment on Species Richness and Abundance in the Mediterranean Basin: A Meta-Analysis

PubMed Central

Plieninger, Tobias; Hui, Cang; Gaertner, Mirijam; Huntsinger, Lynn

2014-01-01

Land abandonment is common in the Mediterranean Basin, a global biodiversity hotspot, but little is known about its impacts on biodiversity. To upscale existing case-study insights to the Pan-Mediterranean level, we conducted a meta-analysis of the effects of land abandonment on plant and animal species richness and abundance in agroforestry, arable land, pastures, and permanent crops of the Mediterranean Basin. In particular, we investigated (1) which taxonomic groups (arthropods, birds, lichen, vascular plants) are more affected by land abandonment; (2) at which spatial and temporal scales the effect of land abandonment on species richness and abundance is pronounced; (3) whether previous land use and current protected area status affect the magnitude of changes in the number and abundance of species; and (4) how prevailing landforms and climate modify the impacts of land abandonment. After identifying 1240 potential studies, 154 cases from 51 studies that offered comparisons of species richness and abundance and had results relevant to our four areas of investigation were selected for meta-analysis. Results are that land abandonment showed slightly increased (effect size  = 0.2109, P<0.0001) plant and animal species richness and abundance overall, though results were heterogeneous, with differences in effect size between taxa, spatial-temporal scales, land uses, landforms, and climate. In conclusion, there is no “one-size-fits-all” conservation approach that applies to the diverse contexts of land abandonment in the Mediterranean Basin. Instead, conservation policies should strive to increase awareness of this heterogeneity and the potential trade-offs after abandonment. The strong role of factors at the farm and landscape scales that was revealed by the analysis indicates that purposeful management at these scales can have a powerful impact on biodiversity. PMID:24865979

Are calanco landforms similar to river basins?

PubMed

Caraballo-Arias, N A; Ferro, V

2017-12-15

In the past badlands have been often considered as ideal field laboratories for studying landscape evolution because of their geometrical similarity to larger fluvial systems. For a given hydrological process, no scientific proof exists that badlands can be considered a model of river basin prototypes. In this paper the measurements carried out on 45 Sicilian calanchi, a type of badlands that appears as a small-scale hydrographic unit, are used to establish their morphological similarity with river systems whose data are available in the literature. At first the geomorphological similarity is studied by identifying the dimensionless groups, which can assume the same value or a scaled one in a fixed ratio, representing drainage basin shape, stream network and relief properties. Then, for each property, the dimensionless groups are calculated for the investigated calanchi and the river basins and their corresponding scale ratio is evaluated. The applicability of Hack's, Horton's and Melton's laws for establishing similarity criteria is also tested. The developed analysis allows to conclude that a quantitative morphological similarity between calanco landforms and river basins can be established using commonly applied dimensionless groups. In particular, the analysis showed that i) calanchi and river basins have a geometrically similar shape respect to the parameters Rf and Re with a scale factor close to 1, ii) calanchi and river basins are similar respect to the bifurcation and length ratios (λ=1), iii) for the investigated calanchi the Melton number assumes values less than that (0.694) corresponding to the river case and a scale ratio ranging from 0.52 and 0.78 can be used, iv) calanchi and river basins have similar mean relief ratio values (λ=1.13) and v) calanchi present active geomorphic processes and therefore fall in a more juvenile stage with respect to river basins. Copyright © 2017 Elsevier B.V. All rights reserved.

Comprehensive assessment of soil erosion risk for better land use planning in river basins: Case study of the Upper Blue Nile River.

PubMed

Haregeweyn, Nigussie; Tsunekawa, Atsushi; Poesen, Jean; Tsubo, Mitsuru; Meshesha, Derege Tsegaye; Fenta, Ayele Almaw; Nyssen, Jan; Adgo, Enyew

2017-01-01

In the drought-prone Upper Blue Nile River (UBNR) basin of Ethiopia, soil erosion by water results in significant consequences that also affect downstream countries. However, there have been limited comprehensive studies of this and other basins with diverse agroecologies. We analyzed the variability of gross soil loss and sediment yield rates under present and expected future conditions using a newly devised methodological framework. The results showed that the basin generates an average soil loss rate of 27.5tha -1 yr -1 and a gross soil loss of ca. 473Mtyr -1 , of which, at least 10% comes from gully erosion and 26.7% leaves Ethiopia. In a factor analysis, variation in agroecology (average factor score=1.32) and slope (1.28) were the two factors most responsible for this high spatial variability. About 39% of the basin area is experiencing severe to very severe (>30tha -1 yr -1 ) soil erosion risk, which is strongly linked to population density. Severe or very severe soil erosion affects the largest proportion of land in three subbasins of the UBNR basin: Blue Nile 4 (53.9%), Blue Nile 3 (45.1%), and Jema Shet (42.5%). If appropriate soil and water conservation practices targeted ca. 77.3% of the area with moderate to severe erosion (>15tha -1 yr -1 ), the total soil loss from the basin could be reduced by ca. 52%. Our methodological framework identified the potential risk for soil erosion in large-scale zones, and with a more sophisticated model and input data of higher spatial and temporal resolution, results could be specified locally within these risk zones. Accurate assessment of soil erosion in the UBNR basin would support sustainable use of the basin's land resources and possibly open up prospects for cooperation in the Eastern Nile region. Copyright © 2016 Office national des forêts. Published by Elsevier B.V. All rights reserved.

Fates of eroded soil organic carbon: Mississippi Basin case study

USGS Publications Warehouse

Smith, S.V.; Sleezer, R.O.; Renwick, W.H.; Buddemeier, R.W.

2005-01-01

We have developed a mass balance analysis of organic carbon (OC) across the five major river subsystems of the Mississippi (MS) Basin (an area of 3.2 ?? 106 km2). This largely agricultural landscape undergoes a bulk soil erosion rate of ???480 t??km -2??yr-1 (???1500 ?? 106 t/yr, across the MS Basin), and a soil organic carbon (SOC) erosion rate of ???7 t??km-2??yr-1 (???22 ?? 106 t/yr). Erosion translocates upland SOC to alluvial deposits, water impoundments, and the ocean. Soil erosion is generally considered to be a net source of CO2 release to the atmosphere in global budgets. However, our results indicate that SOC erosion and relocation of soil apparently can reduce the net SOC oxidation rate of the original upland SOC while promoting net replacement of eroded SOC in upland soils that were eroded. Soil erosion at the MS Basin scale is, therefore, a net CO2 sink rather than a source. ?? 2005 by the Ecological Society of America.

PLANNING CHANGE: CASE STUDIES ILLUSTRATING THE BENEFITS OF GIS AND LAND-USE DATA IN ENVIRONMENTAL PLANNING

EPA Science Inventory

A well-established protocol for planning environmentally sustainable development has yet to be agreed upon. Experiences from two highly-studied basins in the United States illustrate some early attempts, their successes, and the obstacles that continue to impede widespread adopt...

Regional and Household Adaptation Strategies to Climate Extremes: the Case Study of the Beava River Basin, the Czech Republic

NASA Astrophysics Data System (ADS)

Duží, Barbora; Stojanov, Robert; Vikhrov, Dmytro

2013-04-01

We investigate regional and household adaptation strategies in the region affected by climate extremes, focusing on floods occurrence during past 15 years period. The main research question is: What is the overall state of adaptation measurements to climate extremes on the Bečva river basin? Target area is located along upper and middle part of the Bečva river basin in the east of the Czech Republic. The main theoretical concepts draw from differentiations between coping/adaptation strategies to climate extremes and theory of focusing event as a starter of changes in attention and agenda of problem solution. We apply mixed empirical research and case study approach. First we use qualitative research to serve as an initial entrance to the issue, to find out the perception of adaptation progress and preparedness to climate extremes on regional level. We conducted deep interviews (N=20) with relevant stakeholders. We proceed with quantitative research through the conducting face-to face questionnaires with household residents (N=305) in no, low and no risk area in relation to flood occurrence. We designed set of questions to find out relation among experiences with flood, the level of damages and applied emergency and adaptation measurements.

Beneficial effects on water management of simple hydraulic structures in wetland systems: the Vallevecchia case study, Italy.

PubMed

Carrer, G M; Bonato, M; Smania, D; Barausse, A; Comis, C; Palmeri, L

2011-01-01

Conflicting water uses in coastal zones demand integrated approaches to achieve sustainable water resources management, protecting water quality while allowing those human activities which rely upon aquatic ecosystem services to thrive. This case study shows that the creation and simple management of hydraulic structures within constructed wetlands can markedly reduce the non-point pollution from agriculture and, simultaneously, benefit agricultural activities, particularly during hot and dry periods. The Vallevecchia wetland system is based on a reclaimed 900 ha-large drainage basin in Northern Italy, where droughts recently impacted agriculture causing water scarcity and saltwater intrusion. Rainwater and drained water are recirculated inside the system to limit saltwater intrusion, provide irrigation water during dry periods and reduce the agricultural nutrient loads discharged into the bordering, eutrophic Adriatic Sea. Monitoring (2003-2009) of water quality and flows highlights that the construction (ended in 2005) of a gated spillway to control the outflow, and of a 200,000 m3 basin for water storage, dramatically increased the removal of nutrients within the system. Strikingly, this improvement was achieved with a minimal management effort, e.g., each year the storage basin was filled once: a simple management of the hydraulic structures would greatly enhance the system efficiency, and store more water to irrigate and limit saltwater intrusion.

Identifying the causes of water crises: A configurational frequency analysis of 22 basins world wide

NASA Astrophysics Data System (ADS)

Srinivasan, V.; Gorelick, S.; Lambin, E.; Rozelle, S.; Thompson, B.

2010-12-01

Freshwater "scarcity" has been identified as being a major problem world-wide, but it is surprisingly hard to assess if water is truly scarce at a global or even regional scale. Most empirical water research remains location specific. Characterizing water problems, transferring lessons across regions, to develop a synthesized global view of water issues remains a challenge. In this study we attempt a systematic understanding of water problems across regions. We compared case studies of basins across different regions of the world using configurational frequency analysis. Because water crises are multi-symptom and multi-causal, a major challenge was to categorize water problems so as to make comparisons across cases meaningful. In this study, we focused strictly on water unsustainability, viz. the inability to sustain current levels of the anthropogenic (drinking water, food, power, livelihood) and natural (aquatic species, wetlands) into the future. For each case, the causes of three outcome variables, groundwater declines, surface water declines and aquatic ecosystem declines, were classified and coded. We conducted a meta-analysis in which clusters of peer-reviewed papers by interdisciplinary teams were considered to ensure that the results were not biased towards factors privileged by any one discipline. Based on our final sample of 22 case study river basins, some clear patterns emerged. The meta-analysis suggests that water resources managers have long overemphasized the factors governing supply of water resources and while insufficient attention has been paid to the factors driving demand. Overall, uncontrolled increase in demand was twice as frequent as declines in availability due to climate change or decreased recharge. Moreover, groundwater and surface water declines showed distinct causal pathways. Uncontrolled increases in demand due to lack of credible enforcement were a key factor driving groundwater declines; while increased upstream abstractions, inadequate infrastructure investments, and pollution were dominant causes of surface water declines.

Investigating the relation between the geometric properties of river basins and the filtering parameters for regional land hydrology applications using GRACE models

NASA Astrophysics Data System (ADS)

Piretzidis, Dimitrios; Sideris, Michael G.

2016-04-01

This study investigates the possibilities of local hydrology signal extraction using GRACE data and conventional filtering techniques. The impact of the basin shape has also been studied in order to derive empirical rules for tuning the GRACE filter parameters. GRACE CSR Release 05 monthly solutions were used from April 2002 to August 2015 (161 monthly solutions in total). SLR data were also used to replace the GRACE C2,0 coefficient, and a de-correlation filter with optimal parameters for CSR Release 05 data was applied to attenuate the correlation errors of monthly mass differences. For basins located at higher latitudes, the effect of Glacial Isostatic Adjustment (GIA) was taken into account using the ICE-6G model. The study focuses on three geometric properties, i.e., the area, the convexity and the width in the longitudinal direction, of 100 basins with global distribution. Two experiments have been performed. The first one deals with the determination of the Gaussian smoothing radius that minimizes the gaussianity of GRACE equivalent water height (EWH) over the selected basins. The EWH kurtosis was selected as a metric of gaussianity. The second experiment focuses on the derivation of the Gaussian smoothing radius that minimizes the RMS difference between GRACE data and a hydrology model. The GLDAS 1.0 Noah hydrology model was chosen, which shows good agreement with GRACE data according to previous studies. Early results show that there is an apparent relation between the geometric attributes of the basins examined and the Gaussian radius derived from the two experiments. The kurtosis analysis experiment tends to underestimate the optimal Gaussian radius, which is close to 200-300 km in many cases. Empirical rules for the selection of the Gaussian radius have been also developed for sub-regional scale basins.

Characterizing Congo Basin rainfall and climate using Tropical Rainfall Measuring Mission (TRMM) satellite data and limited rain gauge ground observations

USGS Publications Warehouse

Munzimi, Yolande A.; Hansen, Matthew C.; Adusei, Bernard; Senay, Gabriel B.

2015-01-01

Quantitative understanding of Congo River basin hydrological behavior is poor because of the basin’s limited hydrometeorological observation network. In cases such as the Congo basin where ground data are scarce, satellite-based estimates of rainfall, such as those from the joint NASA/JAXA Tropical Rainfall Measuring Mission (TRMM), can be used to quantify rainfall patterns. This study tests and reports the use of limited rainfall gauge data within the Democratic Republic of Congo (DRC) to recalibrate a TRMM science product (TRMM 3B42, version 6) in characterizing precipitation and climate in the Congo basin. Rainfall estimates from TRMM 3B42, version 6, are compared and adjusted using ground precipitation data from 12 DRC meteorological stations from 1998 to 2007. Adjustment is achieved on a monthly scale by using a regression-tree algorithm. The output is a new, basin-specific estimate of monthly and annual rainfall and climate types across the Congo basin. This new product and the latest version-7 TRMM 3B43 science product are validated by using an independent long-term dataset of historical isohyets. Standard errors of the estimate, root-mean-square errors, and regression coefficients r were slightly and uniformly better with the recalibration from this study when compared with the 3B43 product (mean monthly standard errors of 31 and 40 mm of precipitation and mean r2 of 0.85 and 0.82, respectively), but the 3B43 product was slightly better in terms of bias estimation (1.02 and 1.00). Despite reasonable doubts that have been expressed in studies of other tropical regions, within the Congo basin the TRMM science product (3B43) performed in a manner that is comparable to the performance of the recalibrated product that is described in this study.

Spatial scale effect on sediment dynamics in basin-wide floods within a typical agro-watershed: A case study in the hilly loess region of the Chinese Loess Plateau.

PubMed

Zhang, Le-Tao; Li, Zhan-Bin; Wang, Shan-Shan

2016-12-01

Scale issues, which have been extensively studied in the domain of soil erosion, are considerably significant in geomorphologic processes and hydrologic modelling. However, relatively scarce efforts have been made to quantify the spatial scale effect on event-based sediment dynamics in basin-wide floods. To address this issue, sediment-runoff yield data of 44 basin-wide flood events were collected from gauging stations at the Chabagou river basin, a typical agro-basin (unmanaged) in the hilly loess region of the Chinese Loess Plateau. Thus, the spatial scale effect on event-based sediment dynamics was investigated in the basin system across three different spatial scales from sublateral to basin outlet. Results showed that the event-based suspended sediment concentration, as well as the intra- and inter-scale flow-sediment relationships remained spatially constant. Hence, almost all the sediment-laden flows can reach at the detachment-limited maximum concentration across scales, specifically for hyperconcentrated flows. Consequently, limited influence was exerted by upstream sediment-laden flow on downstream sediment output, particularly for major sediment-producing events. However, flood peak discharge instead of total flood runoff amount can better interpret the dynamics of sediment yield across scales. As a composite parameter, the proposed stream energy factor combines flood runoff depth and flood peak discharge, thereby showing more advantages to describe the event-based inter-scale flow-sediment relationship than other flow-related variables. Overall, this study demonstrates the process-specific characteristics of soil erosion by water flows in the basin system. Therefore, event-based sediment control should be oriented by the process to cut off the connectivity of hyperconcentrated flows and redistribute the erosive energy of flowing water in terms of temporality and spatiality. Furthermore, evaluation of soil conservation benefits should be based on the process of runoff regulation to comprehensively assess the efficiency of anti-erosion strategies in sediment control at the basin scale. Copyright © 2016. Published by Elsevier B.V.

A framework model for water-sharing among co-basin states of a river basin

NASA Astrophysics Data System (ADS)

Garg, N. K.; Azad, Shambhu

2018-05-01

A new framework model is presented in this study for sharing of water in a river basin using certain governing variables, in an effort to enhance the objectivity for a reasonable and equitable allocation of water among co-basin states. The governing variables were normalised to reduce the governing variables of different co-basin states of a river basin on same scale. In the absence of objective methods for evaluating the weights to be assigned to co-basin states for water allocation, a framework was conceptualised and formulated to determine the normalised weighting factors of different co-basin states as a function of the governing variables. The water allocation to any co-basin state had been assumed to be proportional to its struggle for equity, which in turn was assumed to be a function of the normalised discontent, satisfaction, and weighting factors of each co-basin state. System dynamics was used effectively to represent and solve the proposed model formulation. The proposed model was successfully applied to the Vamsadhara river basin located in the South-Eastern part of India, and a sensitivity analysis of the proposed model parameters was carried out to prove its robustness in terms of the proposed model convergence and validity over the broad spectrum values of the proposed model parameters. The solution converged quickly to a final allocation of 1444 million cubic metre (MCM) in the case of the Odisha co-basin state, and to 1067 MCM for the Andhra Pradesh co-basin state. The sensitivity analysis showed that the proposed model's allocation varied from 1584 MCM to 1336 MCM for Odisha state and from 927 to 1175 MCM for Andhra, depending upon the importance weights given to the governing variables for the calculation of the weighting factors. Thus, the proposed model was found to be very flexible to explore various policy options to arrive at a decision in a water sharing problem. It can therefore be effectively applied to any trans-boundary problem where there is conflict about water-sharing among co-basin states.

Early evolution of the southern margin of the Neuquén Basin, Argentina: Tectono-stratigraphic implications for rift evolution and exploration of hydrocarbon plays

NASA Astrophysics Data System (ADS)

D'Elia, Leandro; Bilmes, Andrés; Franzese, Juan R.; Veiga, Gonzalo D.; Hernández, Mariano; Muravchik, Martín

2015-12-01

Long-lived rift basins are characterized by a complex structural and tectonic evolution. They present significant lateral and vertical stratigraphic variations that determine diverse basin-patterns at different timing, scale and location. These issues cause difficulties to establish facies models, correlations and stratal stacking patterns of the fault-related stratigraphy, specially when exploration of hydrocarbon plays proceeds on the subsurface of a basin. The present case study corresponds to the rift-successions of the Neuquén Basin. This basin formed in response to continental extension that took place at the western margin of Gondwana during the Late Triassic-Early Jurassic. A tectono-stratigraphic analysis of the initial successions of the southern part of the Neuquén Basin was carried out. Three syn-rift sequences were determined. These syn-rift sequences were located in different extensional depocentres during the rifting phases. The specific periods of rifting show distinctly different structural and stratigraphic styles: from non-volcanic to volcanic successions and/or from continental to marine sedimentation. The results were compared with surface and subsurface interpretations performed for other depocentres of the basin, devising an integrated rifting scheme for the whole basin. The more accepted tectono-stratigraphic scheme that assumes the deposits of the first marine transgression (Cuyo Cycle) as indicative of the onset of a post-rift phase is reconsidered. In the southern part of the basin, the marine deposits (lower Cuyo Cycle) were integrated into the syn-rift phase, implying the existence of different tectonic signatures for Cuyo Cycle along the basin. The rift climax becomes younger from north to south along the basin. The post-rift initiation followed the diachronic ending of the main syn-rift phase throughout the Neuquén Basin. Thus, initiation of the post-rift stage started in the north and proceeded towards the south, constituting a diachronous post-rift event. This arrangement implies that the lower part of Cuyo Cycle, traditionally related to regional thermal subsidence, may be deposited during either mechanical subsidence or thermal subsidence according to its position within the basin.

Integrated catchment modelling within a strategic planning and decision making process: Werra case study

NASA Astrophysics Data System (ADS)

Dietrich, Jörg; Funke, Markus

Integrated water resources management (IWRM) redefines conventional water management approaches through a closer cross-linkage between environment and society. The role of public participation and socio-economic considerations becomes more important within the planning and decision making process. In this paper we address aspects of the integration of catchment models into such a process taking the implementation of the European Water Framework Directive (WFD) as an example. Within a case study situated in the Werra river basin (Central Germany), a systems analytic decision process model was developed. This model uses the semantics of the Unified Modeling Language (UML) activity model. As an example application, the catchment model SWAT and the water quality model RWQM1 were applied to simulate the effect of phosphorus emissions from non-point and point sources on water quality. The decision process model was able to guide the participants of the case study through the interdisciplinary planning and negotiation of actions. Further improvements of the integration framework include tools for quantitative uncertainty analyses, which are crucial for real life application of models within an IWRM decision making toolbox. For the case study, the multi-criteria assessment of actions indicates that the polluter pays principle can be met at larger scales (sub-catchment or river basin) without significantly compromising cost efficiency for the local situation.

Application of synthetic scenarios to address water resource concerns: A management-guided case study from the Upper Colorado River Basin

USGS Publications Warehouse

McAfee, Stephanie A.; Pederson, Gregory T.; Woodhouse, Connie A.; McCabe, Gregory

2017-01-01

Water managers are increasingly interested in better understanding and planning for projected resource impacts from climate change. In this management-guided study, we use a very large suite of synthetic climate scenarios in a statistical modeling framework to simultaneously evaluate how (1) average temperature and precipitation changes, (2) initial basin conditions, and (3) temporal characteristics of the input climate data influence water-year flow in the Upper Colorado River. The results here suggest that existing studies may underestimate the degree of uncertainty in future streamflow, particularly under moderate temperature and precipitation changes. However, we also find that the relative severity of future flow projections within a given climate scenario can be estimated with simple metrics that characterize the input climate data and basin conditions. These results suggest that simple testing, like the analyses presented in this paper, may be helpful in understanding differences between existing studies or in identifying specific conditions for physically based mechanistic modeling. Both options could reduce overall cost and improve the efficiency of conducting climate change impacts studies.

Conceptual models in exploration geochemistry-The Basin and Range Province of the Western United States and Northern Mexico

USGS Publications Warehouse

Lovering, T.G.; McCarthy, J.H.

1978-01-01

This summary of geochemical exploration in the Basin and Range Province is another in the series of reviews of geochemical-exploration applications covering a large region; this series began in 1975 with a summary for the Canadian Cordillera and Canadian Shield, and was followed in 1976 by a similar summary for Scandinavia (Norden). Rather than adhering strictly to the type of conceptual models applied in those papers, we have made use of generalized landscape geochemistry models related to the nature of concealment of ore deposits. This study is part of a continuing effort to examine and evaluate geochemical-exploration practices in different areas of the world. Twenty case histories of the application of geochemical exploration in both district and regional settings illustrate recent developments in techniques and approaches. Along with other published reports these case histories, exemplifying generalized models of concealed deposits, provide data used to evaluate geochemical-exploration programs and specific sample media. Because blind deposits are increasingly sought in the Basin and Range Province, the use of new sample media or anomaly-enhancement techniques is a necessity. Analysis of vapors or gases emanating from blind deposits is a promising new technique. Certain fractions of stream sediments show anomalies that are weak or not detected in conventional minus 80-mesh fractions. Multi-element analysis of mineralized bedrock may show zoning patterns that indicate depth or direction of ore. Examples of the application of these and other, more conventional methods are indicated in the case histories. The final section of this paper contains a brief evaluation of the applications of all types of sample media to geochemical exploration in the arid environment of the Basin and Range Province. ?? 1978.

Modeling effects of secondary tidal basins on estuarine morphodynamics

NASA Astrophysics Data System (ADS)

Nnafie, Abdel; Van Oyen, Tomas; De Maerschalck, Bart

2017-04-01

Many estuaries are situated in very densely populated areas with high economic activities that often conflict with their ecological values. For centuries, geometry and bathymetry of estuaries have been drastically modified trough engineering works such as embanking, sand extraction, channel deepening, land reclamations, etc. It is generally recognized that these works may increase the tidal range (e.g., Scheldt, Ems, Elbe) and turbidity (e.g., Loire, Ems) in estuaries [cf. Kerner, 2007; Wang et al., 2009; Winterwerp and Wang, 2013; Van Maren et al., 2015b,a]. In recent years, construction of secondary basins (also called retention basins) has gained increasing popularity among coastal managers to reduce tidal range and turbidity [Donner et al., 2012]. Previous studies have shown that location, geometry and number of secondary basins have a significant impact on tidal characteristics and sediment transport [Alebregtse and de Swart, 2014; Roos and Schuttelaars, 2015]. However, knowledge on how these secondary basins affect the morphodynamic development of estuaries on long time scales (order decades to centuries) is still lacking. The specific objectives of this study are twofold. First, to investigate effects of secondary basins on the long-term morphodynamic evolution of estuaries. In particular, effects of the presence of such a basin on the morphodynamic evolution of the main channel in the estuary and the physics underlying channel migration will be examined. For this, the Western Scheldt estuary (situated in the Netherlands) is used as a case study, which used to consist of multiple secondary tidal basins that were located at different positions in the estuary, and which have been gradually closed off between 1800 and 1968. Second, to systematically quantify sensitivity of model results to location, geometry, and to number of secondary basins. To this end, the state-of-the- art numerical model Delft3D is used, which has been successfully applied to morphodynamic modeling of estuaries and other coastal systems [cf. Hibma et al., 2003; Van der Wegen and Roelvink 2008; Dissanayake et al., 2012; Eelkema et al., 2013; Ridderinkhof et al., 2014]. With this contribution it will be shown that the presence of secondary basins causes, among other things, local migration of the main channel in the vicinity of the basin, and it decreases the overall depth of the channel network. These results agree well with findings from an observational study on historical morphological development of the Western Scheldt estuary. References available upon request

Clinical significance of the anterosuperior lymph nodes along the common hepatic artery identified by sentinel node mapping in patients with gastric cancer.

PubMed

Shimada, Ayako; Takeuchi, Hiroya; Kamiya, Satoshi; Fukuda, Kazumasa; Nakamura, Rieko; Takahashi, Tsunehiro; Wada, Norihito; Kawakubo, Hirofumi; Saikawa, Yoshiro; Omori, Tai; Nakahara, Tadaki; Jinzaki, Masahiro; Murakami, Koji; Kitagawa, Yuko

2016-10-01

The sentinel node (SN) concept is safely applied and validated in early gastric cancer. Gastric lymph nodes are divided into five basins with the main gastric arteries, and the anterosuperior lymph nodes with the common hepatic artery (No. 8a) are classified in the right gastric artery (r-GA) basin. Although No. 8a are considered to have lymphatic flow from the r-GA basin, there might be additional multiple lymphatic flows into No. 8a. The aim of this study is to analyze the lymphatic flows to No. 8a and to investigate the clinical significance of No. 8a as a sentinel node (SN No. 8a). Four hundred and twenty-nine patients with cT1N0 or cT2N0 gastric cancer underwent SN mapping. We used technetium-99 tin colloid solution and blue dye as a tracer. We detected SN No. 8a in 35 (8.2 %) patients. In these patients, we detected SN No. 8a with SNs that belonged to the left gastric artery (l-GA) basin (66 %), right gastroepiploic artery (r-GEA) basin (54 %), and right gastric artery (r-GA) basin (46 %). In addition, celiac artery lymph nodes were detected as SNs significantly more frequently. Function-preserving surgery was performed significantly less often in patients with SN No. 8a (p =0.018). We found that SN No. 8a seemed to have lymphatic flow not only from the r-GA basin, but also from the l-GA basin or r-GEA basin. When SN No. 8a are detected, we should be careful to perform function-preserving surgery, even in SN-negative cases.

A Chlorhexidine Solution Reduces Aerobic Organism Growth in Operative Splash Basins in a Randomized Controlled Trial.

PubMed

Lindgren, Kevin E; Pelt, Christopher E; Anderson, Mike B; Peters, Christopher L; Spivak, Emily S; Gililland, Jeremy M

2018-01-01

Despite recommendations against the use of splash basins, due to the potential of bacterial contamination, our observation has been that they continue to be used in operating theaters. In hopes of decontaminating the splash basin, we sought to determine if the addition of chlorhexidine gluconate (CHG) would eliminate aerobic bacterial growth within the splash basin. After Institutional Review Board approval, we began enrollment in a randomized controlled trial comparing 2 splash basin solutions. Splash basins (n = 111) were randomized to either the standard of care (control) solution of sterile water or the experimental solution containing 0.05% CHG. One 20 mL aliquot was taken from the basin at the end of the surgical case and delivered to an independent laboratory. Samples were plated on tryptic soy agar (medium) and incubated at 30°C-35°C to encourage growth. After 48-72 hours, the agar plates were examined for growth and a standard plate count of aerobic cultures was performed. The sterile water group was found to have bacterial growth in 9% of samples compared to no growth in the CHG group (P = .045). The organisms included Micrococcus luteus, Staphylococcus hominis, Gram-variable coccobacilli, and unidentifiable Gram-positive rods. Given the safety and efficacy of a concentration of 0.05% CHG in reducing the bacterial contamination in the operative splash basin, it would seem that if the practice of using a splash basin in the operating theater is to be continued, the addition of an antiseptic solution such as that studied here should be considered. Copyright © 2017 Elsevier Inc. All rights reserved.

Evaluating the impacts of climate and land-use change on the hydrology and nutrient yield in a transboundary river basin: A case study in the 3S River Basin (Sekong, Sesan, and Srepok).

PubMed

Trang, Nguyen Thi Thuy; Shrestha, Sangam; Shrestha, Manish; Datta, Avishek; Kawasaki, Akiyuki

2017-01-15

Assessment of the climate and land-use change impacts on the hydrology and water quality of a river basin is important for the development and management of water resources in the future. The objective of this study was to examine the impact of climate and land-use change on the hydrological regime and nutrient yield from the 3S River Basin (Sekong, Srepok, and Sesan) into the 3S River system in Southeast Asia. The 3S Rivers are important tributaries of the Lower Mekong River, accounting for 16% of its annual flow. This transboundary basin supports the livelihoods of nearly 3.5 million people in the countries of Laos, Vietnam, and Cambodia. To reach a better understanding of the process and fate of pollution (nutrient yield) as well as the hydrological regime, the Soil and Water Assessment Tool (SWAT) was used to simulate water quality and discharge in the 3S River Basin. Future scenarios were developed for three future periods: 2030s (2015-2039), 2060s (2045-2069), and 2090s (2075-2099), using an ensemble of five GCMs (General Circulation Model) simulations: (HadGEM2-AO, CanESM2, IPSL-CM5A-LR, CNRM-CM5, and MPI-ESM-MR), driven by the climate projection for RCPs (Representative Concentration Pathways): RCP4.5 (medium emission) and RCP8.5 (high emission) scenarios, and two land-use change scenarios. The results indicated that the climate in the study area would generally become warmer and wetter under both emission scenarios. Discharge and nutrient yield is predicted to increase in the wet season and decrease in the dry. Overall, the annual discharge and nutrient yield is projected to increase throughout the twenty-first century, suggesting sensitivity in the 3S River Basin to climate and land-use change. The results of this study can assist water resources managers and planners in developing water management strategies for uncertain climate change scenarios in the 3S River Basin. Copyright © 2016 Elsevier B.V. All rights reserved.

Multistability and complex basins in a nonlinear duopoly with price competition and relative profit delegation.

PubMed

Fanti, Luciano; Gori, Luca; Mammana, Cristiana; Michetti, Elisabetta

2016-09-01

In this article, we investigate the local and global dynamics of a nonlinear duopoly model with price-setting firms and managerial delegation contracts (relative profits). Our study aims at clarifying the effects of the interaction between the degree of product differentiation and the weight of manager's bonus on long-term outcomes in two different states: managers behave more aggressively with the rival (competition) under product complementarity and less aggressively with the rival (cooperation) under product substitutability. We combine analytical tools and numerical techniques to reach interesting results such as synchronisation and on-off intermittency of the state variables (in the case of homogeneous attitude of managers) and the existence of chaotic attractors, complex basins of attraction, and multistability (in the case of heterogeneous attitudes of managers). We also give policy insights.

Multistability and complex basins in a nonlinear duopoly with price competition and relative profit delegation

NASA Astrophysics Data System (ADS)

Fanti, Luciano; Gori, Luca; Mammana, Cristiana; Michetti, Elisabetta

2016-09-01

In this article, we investigate the local and global dynamics of a nonlinear duopoly model with price-setting firms and managerial delegation contracts (relative profits). Our study aims at clarifying the effects of the interaction between the degree of product differentiation and the weight of manager's bonus on long-term outcomes in two different states: managers behave more aggressively with the rival (competition) under product complementarity and less aggressively with the rival (cooperation) under product substitutability. We combine analytical tools and numerical techniques to reach interesting results such as synchronisation and on-off intermittency of the state variables (in the case of homogeneous attitude of managers) and the existence of chaotic attractors, complex basins of attraction, and multistability (in the case of heterogeneous attitudes of managers). We also give policy insights.

Effects of deep basins on structural collapse during large subduction earthquakes

USGS Publications Warehouse

Marafi, Nasser A.; Eberhard, Marc O.; Berman, Jeffrey W.; Wirth, Erin A.; Frankel, Arthur

2017-01-01

Deep sedimentary basins are known to increase the intensity of ground motions, but this effect is implicitly considered in seismic hazard maps used in U.S. building codes. The basin amplification of ground motions from subduction earthquakes is particularly important in the Pacific Northwest, where the hazard at long periods is dominated by such earthquakes. This paper evaluates the effects of basins on spectral accelerations, ground-motion duration, spectral shape, and structural collapse using subduction earthquake recordings from basins in Japan that have similar depths as the Puget Lowland basin. For three of the Japanese basins and the Puget Lowland basin, the spectral accelerations were amplified by a factor of 2 to 4 for periods above 2.0 s. The long-duration subduction earthquakes and the effects of basins on spectral shape combined, lower the spectral accelerations at collapse for a set of building archetypes relative to other ground motions. For the hypothetical case in which these motions represent the entire hazard, the archetypes would need to increase up to 3.3 times its strength to compensate for these effects.

Morphometric analysis of the Marmara Sea river basins, Turkey

NASA Astrophysics Data System (ADS)

Elbaşı, Emre; Ozdemir, Hasan

2014-05-01

The drainage basin, the fundamental unit of the fluvial landscape, has been focus of research aimed at understanding the geometric characteristics of the master channel and its tributary network. This geometry is referred to as the basin morphometry and is nicely reviewed by Abrahams (1984). A great amount of research has focused on geometric characteristic of drainage basins, including the topology of the stream networks, and quantitative description of drainage texture, pattern, shape, and relief characteristics. Evaluation of morphometric parameters necessitates the analysis of various drainage parameters such as ordering of the various streams, measurement of basin area and perimeter, length of drainage channels, drainage density (Dd), stream frequency (Fs), bifurcation ratio (Rb), texture ratio (T), basin relief (Bh), Ruggedness number (Rn), time of concentration (Tc), hypsometric curve and integral (Hc and Hi) (Horton, 1932, Schumn, 1956, Strahler, 1957; Verstappen 1983; Keller and Pinter, 2002; Ozdemir and Bird, 2009). These morphometric parameters have generally been used to predict flood peaks, to assess sediment yield, and to estimate erosion rates in the basins. River basins of the Marmara Sea, has an area of approximately 40,000 sqkm, are the most important basins in Turkey based on their dense populations, industry and transportation systems. The primary aim of this study is to determine and analyse of morphometric characteristics of the Marmara Sea river basins using 10 m resolution Digital Elevation Model (DEM) and to evaluate of the results. For these purposes, digital 10 m contour maps scaled 1:25000 and geological maps scaled 1:100000 were used as the main data sources in the study. 10 m resolution DEM data were created using the contour maps and then drainage networks and their watersheds were extracted using D8 pour point model. Finally, linear, areal and relief morphometries were applied to the river basins using Geographic Information Systems (GIS). This study shows that morphometric analysis of the basins in regional level are very important to understand general morphological characteristics of the basins. In this case, tectonic and lithological conditions of the basins have greatly affected the morphometric characteristics of the north and south basins of the Marmara Sea. References Abrahams, AD. 1984. Channel Networks: A Geomorphological Perspective. Water Resources Research, Volume 20, Issue 2, pages 161-188. Horton, R.E. 1932. Drainage basin characteristics. Trans Am Geophys Union 13:350-361. Keller, E.A., Pinter, N. 2002. Active Tectonics Earthquakes, Uplift, and Landscape, Second Edition, Prentice Hall, New Jersey. Ozdemir H., Bird D. 2009. Evaluation of morphometric parameters of drainage networks derived from topographic maps and DEM in point of floods, Environmental Geology, vol.56, pp.1405-1415. Schumm, S.A. 1956. Evolution of drainage systems and slopes in badlands at Perth Amboy, New Jersey. Geol Soc Am Bull 67:597-646. Strahler, A.N. 1957. Quantitative geomorphology of drainage and channel networks. In: Chow YT (ed) Handbook of appliecl hydrology. Me Graw Hill Book Company, New York. Verstappen, H.Th. 1983. Applied geomorphology. ITC, Enschede.

Contrasting Population Structures of Two Vectors of African Trypanosomoses in Burkina Faso: Consequences for Control

PubMed Central

Ravel, Sophie; Vreysen, Marc J. B.; Domagni, Kouadjo T.; Causse, Sandrine; Solano, Philippe; de Meeûs, Thierry

2011-01-01

Background African animal trypanosomosis is a major obstacle to the development of more efficient and sustainable livestock production systems in West Africa. Riverine tsetse species such as Glossina palpalis gambiensis Vanderplank and Glossina tachinoides Westwood are the major vectors. A wide variety of control tactics is available to manage these vectors, but their removal will in most cases only be sustainable if the control effort is targeting an entire tsetse population within a circumscribed area. Methodology/Principal Findings In the present study, genetic variation at microsatellite DNA loci was used to examine the population structure of G. p. gambiensis and G. tachinoides inhabiting four adjacent river basins in Burkina Faso, i.e. the Mouhoun, the Comoé, the Niger and the Sissili River Basins. Isolation by distance was significant for both species across river basins, and dispersal of G. tachinoides was ∼3 times higher than that of G. p. gambiensis. Thus, the data presented indicate that no strong barriers to gene flow exists between riverine tsetse populations in adjacent river basins, especially so for G. tachinoides. Conclusions/Significance Therefore, potential re-invasion of flies from adjacent river basins will have to be prevented by establishing buffer zones between the Mouhoun and the other river basin(s), in the framework of the PATTEC (Pan African Tsetse and Trypanosomosis Eradication Campaign) eradication project that is presently targeting the northern part of the Mouhoun River Basin. We argue that these genetic analyses should always be part of the baseline data collection before any tsetse control project is initiated. PMID:21738812

Evaluating the Impacts of Urbanization on Hydrological Processes and Water Resources by Comparing Two Neighboring Basins

NASA Astrophysics Data System (ADS)

Shao, M.; Zhao, G.; Gao, H.

2017-12-01

Texas, the fastest growing state in the US, has seen significant land cover/land use change due to urbanization over the past decades. With most of the region being arid/semi-arid, water issues are unprecedentedly pressing. Among the 15 major river basins, two adjacent river basins located in south-central Texas—the San Antonio River Basin (SARB) and the Guadalupe River Basin (GRB)—form an ideal testbed for evaluating the impacts of urbanization on both hydrological processes and water resources. These two basins are similar in size and in climate pattern, but differ in terms of urbanization progress. In SARB, where the city of San Antonio is located, the impervious area has increased from 0.6% (1929) to 7.8% (2011). In contrast, there is little land cover change in the GRB. With regard to the underground components, both basins intersect with the Edward Aquifer (more than 15% of basin area in both cases). The Edward Aquifer acts as one of the major municipal water supplies for San Antonio, and as the water source for local agricultural uses (and for the surrounding habitat). This aquifer has the characteristic of being highly sensitive to changes in surface water conditions, like the descending trend of the underground water table due to over exploitation. In this study, a distributed hydrologic model—DHSVM (the Distributed Hydrology Soil Vegetation Model)—is used to compare the hydrologic characteristics (and their impacts on water resources) over the two basins. With a 200m spatial resolution, the model is calibrated and validated during the historical period over both basins. The objectives of the comparisons are two-fold: First, the urbanization effects on peak flows are evaluated for selected extreme rainfall events; Second, the Edward Aquifer recharge rate from surface water under flood and/or drought conditions within the two basins is analyzed. Furthermore, future urbanization scenarios are tested to provide information relevant to decision making.

The Incidence of Local Water Pollution Abatement Expenditures: A Case Study of the Merrimack River Basin (1974)

EPA Pesticide Factsheets

Part I is an analysis of the determinants of local government expenditures on water pollution abatement facilities. Part II is an investigation of the incidence of costs and benefits of public environmental programs.

GIS and remote sensing techniques for the assessment of land use changes impact on flood hydrology: the case study of Yialias Basin in Cyprus

NASA Astrophysics Data System (ADS)

Alexakis, D. D.; Gryllakis, M. G.; Koutroulis, A. G.; Agapiou, A.; Themistocleous, K.; Tsanis, I. K.; Michaelides, S.; Pashiardis, S.; Demetriou, C.; Aristeidou, K.; Retalis, A.; Tymvios, F.; Hadjimitsis, D. G.

2013-09-01

Flooding is one of the most common natural disasters worldwide, leading to economic losses and loss of human lives. This paper highlights the hydrological effects of multi-temporal land use changes in flood hazard within the Yialias catchment area, located in central Cyprus. Calibrated hydrological and hydraulic models were used to describe the hydrological processes and internal basin dynamics of the three major sub-basins, in order to study the diachronic effects of land use changes. For the implementation of the hydrological model, land use, soil and hydrometeorological data were incorporated. The climatic and stream flow data were derived from rain and flow gauge stations located in the wider area of the watershed basin. In addition, the land use and soil data were extracted after the application of object oriented nearest neighbor algorithms of ASTER satellite images. Subsequently, the CA-Markov chain analysis was implemented to predict the 2020 Land use/Land cover (LULC) map and incorporate it to the hydrological impact assessment. The results denoted the increase of runoff in the catchment area due to the recorded extensive urban sprawl phenomenon of the last decade.

Water Energy Simulation Toolset

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nguyen, Thuy; Jeffers, Robert

The Water-Energy Simulation Toolset (WEST) is an interactive simulation model that helps visualize impacts of different stakeholders on water quantity and quality of a watershed. The case study is applied for the Snake River Basin with the fictional name Cutthroat River Basin. There are four groups of stakeholders of interest: hydropower, agriculture, flood control, and environmental protection. Currently, the quality component depicts nitrogen-nitrate contaminant. Users can easily interact with the model by changing certain inputs (climate change, fertilizer inputs, etc.) to observe the change over the entire system. Users can also change certain parameters to test their management policy.

3D structure of a complex of transform basins from gravity data, a case study from the central Dead Sea fault

NASA Astrophysics Data System (ADS)

Rosenthal, Michal; Schattner, Uri; Ben-Avraham, Zvi

2017-04-01

The Kinneret-Bet She'an (KBS) basin complex comprises the Sea of Galilee, Kinarot, and Bet She'an sub-basins. The complex developed at the intersection between two major tectonic boundaries: the Oligo-Miocene Azraq-Sirhan failed rift, that later developed into the southern Galilee basins and Carmel-Gilboa fault system; and the Dead Sea fault (DSF) plate boundary that developed since the Miocene. Despite numerous studies, KBS still remains one of the enigmatic basin complexes. Its structure, stratigraphy and development are vaguely understood - both inside the basin and in correlation with its surroundings. Our study presents a new and comprehensive 3D model for the structure of KBS complex. It is based on all available gravity measurements, adopted from the national gravity database, and new gravity measurements, collected in cooperation with the Geological Survey of Israel and funded by the Ministry of National Infrastructure, Energy and Water Resources. The gravity data were integrated with constraints from boreholes, surface geology, seismic surveys, potential field studies and teleseismic tomography. The dense distribution of gravity data [1] provides suitable coverage for modeling the deep structure in three dimensions. The model details the spatial distribution, depth, thickness and density of the following regional units within the KBS complex and across its surroundings: upper crust, pre-Senonian sediments, Senonian and Cenozoic sediments, Miocene volcanics, Pliocene and Quaternary volcanics. Additional local units include salt, gabbro and pyroclasts. Results indicate that the KBS complex comprises two sub-basins separated by a structural saddle: Kinneret-Kinarot ( 6-7 km deep, 45 km long) and Bet She'an ( 4 km deep, 10 km long) sub-basin. A 500 m thick layer of Miocene volcanics appears across the Bet She'an sub-basin, yet missing from the Kinneret-Kinarot sub-basin. Between the basins Zemah-1 borehole penetrated a salt unit. The model indicates that this unit is a part of a thick (1250 m) dome-shaped, perhaps diapiric, structure. A relatively thin (350 m) salt unit fills the Kinneret-Kinarot sub-basin. Above, a 700 m thick layer of Pliocene volcanics fills the entire KBS complex. These volcanics are uplifted in the Zemah area by 200 m. The Pliocene volcanics dip northward from Zemah towards the center of the Sea of Galilee, and further north the Pliocene volcanics dip southward from Korazim towards the center of the Sea of Galilee. The depth differences exceed 3 km across a distance of 15 km, forming a 11° slope below the younger Quaternary fill of the basin. A low-density, probably pyroclastic, lens is calculated within the uppermost 2 km of the Sea of Galilee fill. Scenarios for the development of the basin are discussed. [1] Rosenthal, M., Segev, A., Rybakov, M., Lyakhovsky, V. and Ben-Avraham, Z. (2015) The deep structure and density distribution of northern Israel and its surroundings. GSI Report No. GSI/12/2015, 33 pages, Jerusalem.

Assessment of Climate Change and Agricultural Land Use Change on Streamflow Input to Devils Lake: A Case Study of the Mauvais Coulee Sub-basin

NASA Astrophysics Data System (ADS)

Jackson, C.; Todhunter, P. E.

2017-12-01

Since 1993, Devils Lake in North Dakota has experienced a prolonged rise in lake level and flooding of the lake's neighboring areas within the closed basin system. Understanding the relative contribution of climate change and land use change is needed to explain the historical rise in lake level, and to evaluate the potential impact of anthropogenic climate change upon future lake conditions and management. Four methodologies were considered to examine the relative contribution of climatic and human landscape drivers to streamflow variations: statistical, ecohydrologic, physically-based modeling, and elasticity of streamflow; for this study, ecohydrologic and climate elasticity were selected. Agricultural statistics determined that Towner and Ramsey counties underwent a crop conversion from small grains to row crops within the last 30 years. Through the Topographic Wetness Index (TWI), a 10 meter resolution DEM confirmed the presence of innumerable wetland depressions within the non-contributing area of the Mauvais Coulee Sub-basin. Although the ecohydrologic and climate elasticity methodologies are the most commonly used in literature, they make assumptions that are not applicable to basin conditions. A modified and more informed approach to the use of these methods was applied to account for these unique sub-basin characteristics. Ultimately, hydroclimatic variability was determined as the largest driver to streamflow variation in Mauvais Coulee and Devils Lake.

Multi-scale constraints of sediment source to sink systems in frontier basins: a forward stratigraphic modeling case study of the Levant region

NASA Astrophysics Data System (ADS)

Hawie, Nicolas; Deschamps, Remy; Granjeon, Didier; Nader, Fadi-Henri; Gorini, Christian; Müller, Carla; Montadert, Lucien; Baudin, François

2015-04-01

Recent scientific work underlined the presence of a thick Cenozoic infill in the Levant Basin reaching up to 12 km. Interestingly; restricted sedimentation was observed along the Levant margin in the Cenozoic. Since the Late Eocene successive regional geodynamic events affecting Afro-Arabia and Eurasia (collision and strike slip deformation)induced fast marginal uplifts. The initiation of local and long-lived regional drainage systems in the Oligo-Miocene period (e.g. Lebanon versus Nile) provoked a change in the depositional pattern along the Levant margin and basin. A shift from carbonate dominated environments into clastic rich systems has been observed. Through this communication we explore the importance of multi-scale constraints (i.e.,seismic, well and field data) in the quantification of the subsidence history, sediment transport and deposition of a Middle-Upper Miocene "multi-source" to sink system along the northernLevant frontier region. We prove through a comprehensive forward stratigraphic modeling workflow that the contribution to the infill of the northern Levant Basin (offshore Lebanon) is split in between proximal and more distal clastic sources as well as in situ carbonate/hemipelagic deposition. In a wider perspective this work falls under the umbrella of multi-disciplinary source to sink studies that investigate the impact of geodynamic events on basin/margin architectural evolutions, consequent sedimentary infill and thus on petroleum systems assessment.

Problematising and conceptualising local participation in transboundary water resources management: The case of Limpopo river basin in Zimbabwe

NASA Astrophysics Data System (ADS)

Fatch, Joanna J.; Manzungu, Emmanuel; Mabiza, Collin

IWRM-led water reforms in southern Africa have emphasised the creation of new stakeholder institutions with little explanation of how they will operate at different levels, especially at the local level. A case in point is the subsidiarity principle, which advocates for water management to be undertaken at the lowest appropriate level. The main objective of the study was to investigate the conceptualisation and application of the subsidiarity principle in the Limpopo river basin in Zimbabwe. This was done by analysing how state-led frameworks at the regional, basin, national and local level provided for local participation. These frameworks were compared to a bottom-up approach based on action research in three second tier local government administrative units (wards) in Shashe subcatchment of Mzingwane catchment. The catchment represents the entirety of the Limpopo basin in Zimbabwe. Data collection was based on document reviews, key informants, focus group discussions and participatory observations. In general the top-down efforts were found to express intent but lacked appropriately conceptualised implementation guidelines. Views of local people regarding how they could meaningfully participate in transboundary water resource management were based on practical considerations rather than theoretical abstractions. This was shown by a different conceptualisation of stakeholder identification and representation, demarcation of boundaries, role of intermediate institutions, and direct participation of local people at the basin level. The paper concludes that a bottom-up institutional model can enhance the conceptualisation and application of the subsidiarity principle. It also provides evidence that prescriptive approaches may not be the best way to achieve participatory governance in transboundary water resource management.

Preliminary analysis of the role of lake basin morphology on the modern diatom flora in the Ruby Mountains and East Humboldt Range, Nevada, USA

USGS Publications Warehouse

Starratt, Scott W.

2014-01-01

As paleolimnologists, we often look at the world through a 5-cm-diameter hole in the bottom of a lake, and although a number of studies have shown that a single core in the deepest part of a lake does not necessarily reflect the entire diatom flora, time and money often limit our ability to collect more than one core from a given site. This preliminary study is part of a multidisciplinary research project to understand Holocene climate variability in alpine regions of the Great Basin, and ultimately, to compare these high elevation records to the better studied pluvial records from adjacent valleys, in this case, the Ruby Valley.

Basin characterization and determination of hydraulic connectivity of mega basins using integrated methods: (The case of Baro-Akobo and mega watershed beyond)

NASA Astrophysics Data System (ADS)

Alemayehu, Taye; Kebede, Tesfaye; Liu, Lanbo

2018-01-01

Despite being the longest river and the fourth in drainage area, Nile River has the lowest discharge per unit areas among the top ten rivers of the world. Understanding the hydrologic significance of the regional litho-stratigraphy and structures help to better understand the hydrodynamics. This work is aimed at characterizing the Baro-Akobo-Sobbat sub-basin of Nile and determine trans-basin flows. Integrated method is used to characterize the basin and determine the Baro-Akobo-Sobbat sub-basin's relationship with African Mesozoic Rifts. Oil and water well drilling logs; aeromagnetic, gravity and vertical electrical sounding data; and various study reports are used to establish regional lithostratigraphic correlations and determine trans-regional hydrogeological connectivity. A total of 633 samples collected from wells, springs, rivers, lakes, swamps and rain water are analysed for their chemical, stable isotopes, tritium and radon properties. The Baro-Akobo river basin is commonly presumed to have good groundwater potential, particularly in its lowland plain. However, it has poor exploitable groundwater potential and recharge rate due to the extensive clay cover, limited retention capacity and the loss of the bulk of the groundwaters through regional geological structures to the deep seated continental sediments; presumably reaching the hydraulically connected African Mesozoic Rifts; mainly Melut and Muglad. The deep underground northward flows, along Nile River is, presumably, retarded by Central African Shear Zone in the Sudan.

Towards an equitable allocation of the cost of a global change adaptation plan at the river basin scale: going beyond the perfect cooperation assumption

NASA Astrophysics Data System (ADS)

Girard, Corentin; Rinaudo, Jean-Daniel; Pulido-Velázquez, Manuel

2015-04-01

Adaptation to global change is a key issue in the planning of water resource systems in a changing world. Adaptation has to be efficient, but also equitable in the share of the costs of joint adaptation at the river basin scale. Least-cost hydro-economic optimization models have been helpful at defining efficient adaptation strategies. However, they often rely on the assumption of a "perfect cooperation" among the stakeholders, required for reaching the optimal solution. Nowadays, most adaptation decisions have to be agreed among the different actors in charge of their implementation, thus challenging the validity of a perfect command-and-control solution. As a first attempt to over-pass this limitation, our work presents a method to allocate the cost of an efficient adaptation programme of measures among the different stakeholders at the river basin scale. Principles of equity are used to define cost allocation scenarios from different perspectives, combining elements from cooperative game theory and axioms from social justice to bring some "food for thought" in the decision making process of adaptation. To illustrate the type of interactions between stakeholders in a river basin, the method has been applied in a French case study, the Orb river basin. Located on the northern rim of the Mediterranean Sea, this river basin is experiencing changes in demand patterns, and its water resources will be impacted by climate change, calling for the design of an adaptation plan. A least-cost river basin optimization model (LCRBOM) has been developed under GAMS to select the combination of demand- and supply-side adaptation measures that allows meeting quantitative water management targets at the river basin scale in a global change context. The optimal adaptation plan encompasses measures in both agricultural and urban sectors, up-stream and down-stream of the basin, disregarding the individual interests of the stakeholders. In order to ensure equity in the cost allocation of the adaptation plan, different allocation scenarios are considered. The LCRBOM allows defining a solution space based on economic rationality concepts from cooperative game theory (the core of the game), and then, to define equitable allocation of the cost of the programme of measures (the Shapley value and the nucleolus). Moreover, alternative allocation scenarios have been considered based on axiomatic principles of social justice, such as "utilitarian", "prior rights" or "strict equality", applied in the case study area. The comparison of the cost allocation scenarios brings insight to inform the decision making process at the river basin scale and potentially reap the efficiency gains from cooperation in the design of adaptation plan. The study has been partially supported by the IMPADAPT project /CGL2013-48424-C2-1-R) from the Spanish ministry MINECO (Ministerio de Economía y Competitividad) and European FEDER funds. Corentin Girard is supported by a grant from the University Lecturer Training Program (FPU12/03803) of the Ministry of Education, Culture and Sports of Spain.

An analytical approach to separate climate and human contributions to basin streamflow variability

NASA Astrophysics Data System (ADS)

Li, Changbin; Wang, Liuming; Wanrui, Wang; Qi, Jiaguo; Linshan, Yang; Zhang, Yuan; Lei, Wu; Cui, Xia; Wang, Peng

2018-04-01

Climate variability and anthropogenic regulations are two interwoven factors in the ecohydrologic system across large basins. Understanding the roles that these two factors play under various hydrologic conditions is of great significance for basin hydrology and sustainable water utilization. In this study, we present an analytical approach based on coupling water balance method and Budyko hypothesis to derive effectiveness coefficients (ECs) of climate change, as a way to disentangle contributions of it and human activities to the variability of river discharges under different hydro-transitional situations. The climate dominated streamflow change (ΔQc) by EC approach was compared with those deduced by the elasticity method and sensitivity index. The results suggest that the EC approach is valid and applicable for hydrologic study at large basin scale. Analyses of various scenarios revealed that contributions of climate change and human activities to river discharge variation differed among the regions of the study area. Over the past several decades, climate change dominated hydro-transitions from dry to wet, while human activities played key roles in the reduction of streamflow during wet to dry periods. Remarkable decline of discharge in upstream was mainly due to human interventions, although climate contributed more to runoff increasing during dry periods in the semi-arid downstream. Induced effectiveness on streamflow changes indicated a contribution ratio of 49% for climate and 51% for human activities at the basin scale from 1956 to 2015. The mathematic derivation based simple approach, together with the case example of temporal segmentation and spatial zoning, could help people understand variation of river discharge with more details at a large basin scale under the background of climate change and human regulations.

Transient electromagnetic study of basin fill sediments in the Upper San Pedro Basin, Mexico

USGS Publications Warehouse

Bultman, M.W.; Gray, F.

2011-01-01

The Upper San Pedro River Basin in Mexico and the United States is an important riparian corridor that is coming under increasing pressure from growing populations and the associated increase in groundwater withdrawal. Several studies have produced three-dimensional maps of the basin fill sediments in the US portion of the basin but little work has been done in the Mexican portion of the basin. Here, the results of a ground-based transient electromagnetic (TEM) survey in the Upper San Pedro Basin, Mexico are presented. These basin fill sediments are characterized by a 10-40 m deep unsaturated surficial zone which is composed primarily of sands and gravels. In the central portion of the basin this unsaturated zone is usually underlain by a shallow clay layer 20-50 m thick. Beneath this may be more clay, as is usually the case near the San Pedro River, or interbedded sand, silt, and clay to a depth of 200-250 m. As you move away from the river, the upper clay layer disappears and the amount of sand in the sediments increases. At 1-2 km away from the river, sands can occupy up to 50% of the upper 200-250 m of the sediment fill. Below this, clays are always present except where bedrock highs are observed. This lower clay layer begins at a depth of about 200 m in the central portion of the basin (250 m or more at distances greater than 1-2 km from the river) and extends to the bottom of most profiles to depths of 400 m. While the depth of the top of this lower clay layer is probably accurate, its thickness observed in the models may be overestimated due to the relatively low magnetic moment of the TEM system used in this study. The inversion routine used for interpretation is based on a one-dimensional geologic model. This is a layer based model that is isotropic in both the x and y directions. Several survey soundings did not meet this requirement which invalidates the inversion process and the resulting interpretation at these locations. The results from these locations were rejected. ?? 2011 Springer-Verlag (outside the USA).

Effects of Long-Period Ground Motion on Distant Basins: The 1906 San Francisco Earthquake and Comparison with Japanese Cases

NASA Astrophysics Data System (ADS)

Koketsu, K.; Ikegami, Y.; Kimura, T.; Miyake, H.

2006-12-01

Large earthquakes at shallow depths can excite long-period ground motions affecting large-scale structures in distant sedimentary basins. For example, the 1985 Michoacan, Mexico, earthquake caused 20,000 fatalities in Mexico City at an epicentral distance of 400 km, and the 2003 Tokachi-oki, Japan, earthquake damaged oil tanks in the Yufutsu basin 250 km away (Koketsu et al., 2005). Similar long-range effects were also observed during the 2004 off Kii-peninsula earthquake (Miyake and Koketsu, 2005). In order to examine whether the 1906 San Francisco earthquake and the Los Angeles (LA) basin are in such a case or not, we simulate long- period ground motions in almost whole California caused by the earthquake using the finite element method (FEM) with a voxel mesh (Koketsu et al., 2004). The LA basin is located at a distance of about 600 km from the source region of the 1906 San Francisco earthquake. The 3-D heterogeneous velocity structure model for the ground motion simulation is constructed based on the SCEC Unified Velocity Model for southern California and USGS Bay Area Velocity Model for northern California. The source model of the earthquake is constructed according to Wald et al. (1993). Since we use a mesh with intervals of 500m, the voxel FEM can compute seismic waves with frequencies lower than 0.2 Hz. Although ground motions in the south of the source region are smaller than those in the north because of the rupture directivity effect, we can see fairly developed long- period ground motions in the LA basin in the preliminary result of Kimura et al. (2006). However, we obtained only 8cm/s and 25km/s for PGV and peak velocity response spectrum in the LA basin. We modeled the velocity structure up to a depth of only 20km neglecting the Moho reflections, and we did not include layers with Vs smaller than 1.0 km/s. In this study, we include deeper parts and use a more accurate velocity structure model with low-velocity sediments of Vs smaller than 1.0 km/s.

Groundwater quality in the San Diego Drainages Hydrogeologic Province, California

USGS Publications Warehouse

Wright, Michael T.; Belitz, Kenneth

2011-01-01

More than 40 percent of California's drinking water is from groundwater. To protect this vital resource, the State of California created the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The Priority Basin Project of the GAMA Program provides a comprehensive assessment of the State's groundwater quality and increases public access to groundwater-quality information. The San Diego Drainages Hydrogeologic Province (hereinafter referred to as San Diego) is one of the study units being evaluated. The San Diego study unit is approximately 3,900 square miles and consists of the Temecula Valley, Warner Valley, and 12 other alluvial basins (California Department of Water Resources, 2003). The study unit also consists of all areas outside defined groundwater basins that are within 3 kilometers of a public-supply well. The study unit was separated, based primarily on hydrogeologic settings, into four study areas: Temecula Valley, Warner Valley, Alluvial Basins, and Hard Rock (Wright and others, 2005). The sampling density for the Hard Rock study area, which consists of areas outside of groundwater basins, was much lower than for the other study areas. Consequently, aquifer proportions for the Hard Rock study area are not used to calculate the aquifer proportions shown by the pie charts. An assessment of groundwater quality for the Hard Rock study area can be found in Wright and Belitz, 2011. The temperatures in the coastal part of the study unit are mild with dry summers, moist winters, and an average annual rainfall of about 10 inches. The temperatures in the mountainous eastern part of the study unit are cooler than in the coastal part, with an annual precipitation of about 45 inches that occurs mostly in the winter. The primary aquifers consist of Quaternary-age alluvium and weathered bedrock in the Temecula Valley, Warner Valley, and Alluvial Basins study areas, whereas in the Hard Rock study area the primary aquifers consist mainly of fractured and decomposed granite of Mesozoic age. The primary aquifers are defined as those parts of the aquifers corresponding to the perforated intervals of wells listed in the California Department of Public Health (CDPH) database. Public-supply wells typically are drilled to depths between 200 and 700 feet, consist of solid casing from the land surface to a depth of about 60 to 170 feet, and are perforated, or consist of an open hole, below the solid casing. Water quality in the shallow and deep parts of the aquifer system may differ from water quality in the primary aquifers. Municipal water use accounts for approximately 70 percent of water used in the study unit; the majority of the remainder is used for agriculture, industry, and commerce. Groundwater accounts for approximately 8 percent of the municipal supply, and surface water, the majority of which is imported, accounts for the rest. Recharge to groundwater occurs through stream-channel infiltration from rivers and their tributaries, infiltration in engineered recharge basins, and infiltration of water from precipitation and irrigation. The primary source of discharge is water pumped from wells.

Probabilistic Risk Analysis of Run-up and Inundation in Hawaii due to Distant Tsunamis

NASA Astrophysics Data System (ADS)

Gica, E.; Teng, M. H.; Liu, P. L.

2004-12-01

Risk assessment of natural hazards usually includes two aspects, namely, the probability of the natural hazard occurrence and the degree of damage caused by the natural hazard. Our current study is focused on the first aspect, i.e., the development and evaluation of a methodology that can predict the probability of coastal inundation due to distant tsunamis in the Pacific Basin. The calculation of the probability of tsunami inundation could be a simple statistical problem if a sufficiently long record of field data on inundation was available. Unfortunately, such field data are very limited in the Pacific Basin due to the reason that field measurement of inundation requires the physical presence of surveyors on site. In some areas, no field measurements were ever conducted in the past. Fortunately, there are more complete and reliable historical data on earthquakes in the Pacific Basin partly because earthquakes can be measured remotely. There are also numerical simulation models such as the Cornell COMCOT model that can predict tsunami generation by an earthquake, propagation in the open ocean, and inundation onto a coastal land. Our objective is to develop a methodology that can link the probability of earthquakes in the Pacific Basin with the inundation probability in a coastal area. The probabilistic methodology applied here involves the following steps: first, the Pacific Rim is divided into blocks of potential earthquake sources based on the past earthquake record and fault information. Then the COMCOT model is used to predict the inundation at a distant coastal area due to a tsunami generated by an earthquake of a particular magnitude in each source block. This simulation generates a response relationship between the coastal inundation and an earthquake of a particular magnitude and location. Since the earthquake statistics is known for each block, by summing the probability of all earthquakes in the Pacific Rim, the probability of the inundation in a coastal area can be determined through the response relationship. Although the idea of the statistical methodology applied here is not new, this study is the first to apply it to study the probability of inundation caused by earthquake-generated distant tsunamis in the Pacific Basin. As a case study, the methodology is applied to predict the tsunami inundation risk in Hilo Bay in Hawaii. Since relatively more field data on tsunami inundation are available for Hilo Bay, this case study can help to evaluate the applicability of the methodology for predicting tsunami inundation risk in the Pacific Basin. Detailed results will be presented at the AGU meeting.

Temporal evolution of fault systems in the Upper Jurassic of the Central German Molasse Basin: case study Unterhaching

NASA Astrophysics Data System (ADS)

Budach, Ingmar; Moeck, Inga; Lüschen, Ewald; Wolfgramm, Markus

2018-03-01

The structural evolution of faults in foreland basins is linked to a complex basin history ranging from extension to contraction and inversion tectonics. Faults in the Upper Jurassic of the German Molasse Basin, a Cenozoic Alpine foreland basin, play a significant role for geothermal exploration and are therefore imaged, interpreted and studied by 3D seismic reflection data. Beyond this applied aspect, the analysis of these seismic data help to better understand the temporal evolution of faults and respective stress fields. In 2009, a 27 km2 3D seismic reflection survey was conducted around the Unterhaching Gt 2 well, south of Munich. The main focus of this study is an in-depth analysis of a prominent v-shaped fault block structure located at the center of the 3D seismic survey. Two methods were used to study the periodic fault activity and its relative age of the detected faults: (1) horizon flattening and (2) analysis of incremental fault throws. Slip and dilation tendency analyses were conducted afterwards to determine the stresses resolved on the faults in the current stress field. Two possible kinematic models explain the structural evolution: One model assumes a left-lateral strike slip fault in a transpressional regime resulting in a positive flower structure. The other model incorporates crossing conjugate normal faults within a transtensional regime. The interpreted successive fault formation prefers the latter model. The episodic fault activity may enhance fault zone permeability hence reservoir productivity implying that the analysis of periodically active faults represents an important part in successfully targeting geothermal wells.

Central magnetic anomalies of Nectarian-aged lunar impact basins: Probable evidence for an early core dynamo

NASA Astrophysics Data System (ADS)

Hood, Lon L.

2011-02-01

A re-examination of all available low-altitude LP magnetometer data confirms that magnetic anomalies are present in at least four Nectarian-aged lunar basins: Moscoviense, Mendel-Rydberg, Humboldtianum, and Crisium. In three of the four cases, a single main anomaly is present near the basin center while, in the case of Crisium, anomalies are distributed in a semi-circular arc about the basin center. These distributions, together with a lack of other anomalies near the basins, indicate that the sources of the anomalies are genetically associated with the respective basin-forming events. These central basin anomalies are difficult to attribute to shock remanent magnetization of a shocked central uplift and most probably imply thermoremanent magnetization of impact melt rocks in a steady magnetizing field. Iterative forward modeling of the single strongest and most isolated anomaly, the northern Crisium anomaly, yields a paleomagnetic pole position at 81° ± 19°N, 143° ± 31°E, not far from the present rotational pole. Assuming no significant true polar wander since the Crisium impact, this position is consistent with that expected for a core dynamo magnetizing field. Further iterative forward modeling demonstrates that the remaining Crisium anomalies can be approximately simulated assuming a multiple source model with a single magnetization direction equal to that inferred for the northernmost anomaly. This result is most consistent with a steady, large-scale magnetizing field. The inferred mean magnetization intensity within the strongest basin sources is ˜1 A/m assuming a 1-km thickness for the source layer. Future low-altitude orbital and surface magnetometer measurements will more strongly constrain the depth and/or thicknesses of the sources.

An integrated workflow to assess the remaining potential of mature hydrocarbon basins: a case study from Northwest Germany (Upper Jurassic/Lower Cretaceous, Lower Saxony Basin)

NASA Astrophysics Data System (ADS)

Seyfang, Björn; Aigner, Thomas; Munsterman, Dirk K.; Irmen, Anton

2017-04-01

Mature hydrocarbon provinces require a high level of geological understanding in order to extend the lives of producing fields, to replace reserves through smaller targets and to reduce the risks of exploring for more and more subtle hydrocarbon traps. Despite a large number of existing wells in the area studied in this paper, the depositional environments and the stratigraphic architecture were still poorly known. In order to improve the geological understanding, we propose a workflow to assess the remaining reservoir potential of mature hydrocarbon areas, integrating cores, cuttings, well-logs, biostratigraphy and seismic data. This workflow was developed for and is exemplified with the northwest of the Lower Saxony Basin (LSB), a mature hydrocarbon province in northwest Germany, but can be applied in a similar fashion to other areas. Systematic integration of lithofacies analysis, chrono- and sequence stratigraphy, combined with electrofacies analysis and modern digital methods like neural network-based lithology determination and 3D facies modelling provides a high-resolution understanding of the spatial facies and reservoir architecture in the study area. Despite widely correlatable litho-units in the Upper Jurassic and Lower Cretaceous in the LSB, complex heterogeneous sedimentary systems can be found in the basin's marginal parts. Two new play types were determined in the study area, showing a remaining potential for stratigraphic hydrocarbon traps. The results of this exploration scale study also provide the basis for re-evaluations on a field development scale. On a basin scale, this study may encourage further data acquisition and re-evaluations to discover previously unknown reservoirs.

Seasonal Distribution, Biology, and Human Attraction Patterns of Mosquitoes (Diptera: Culicidae) in a Rural Village and Adjacent Forested Site Near Iquitos, Peru

DTIC Science & Technology

2008-11-01

and malarial activity in the Amazon Basin, Loreto Department, Peru , to determine the relative abundance, species diversity, and seasonal and vertical...populations. KEY WORDS Anopheles, bionomics, mosquito ecology, Amazon Basin, Peru Malaria and other arthropod-vectored diseases are on the increase...in the Amazon Basin region of Peru to date. The Puerto Almendra area was selected because human cases of dengue, malaria, Mayaro, Oropouche

Regime shifts and panarchies in regional scale social-ecological water systems

EPA Science Inventory

In this article we summarize histories of nonlinear, complex interactions among societal, legal, and ecosystem dynamics in six North American water basins, as they respond to changing climate. These case studies were chosen to explore the conditions for emergence of adaptive gove...

EFFECTS OF GEOMORPHIC PROCESSES AND HYDROLOGIC REGIMES ON RIPARIAN VEGETATION

EPA Science Inventory

In this chapter, the relationships among riparian vegetation and geomorphic and hydrologic processes in central Great Basin watersheds are evaluated over a range of scales. These relationships are examined through a series of case studies that have been conducted by the Great Ba...

Brugga basin's TACD Model Adaptation to current GIS PCRaster 4.1

NASA Astrophysics Data System (ADS)

Lopez Rozo, Nicolas Antonio; Corzo Perez, Gerald Augusto; Santos Granados, Germán Ricardo

2017-04-01

The process-oriented catchment model TACD (Tracer-Aided Catchment model - Distributed) was developed in the Brugga Basin (Dark Forest, Germany) with a modular structure in the Geographic Information System PCRaster Version 2, in order to dynamically model the natural processes of a complex Basin, such as rainfall, air temperature, solar radiation, evapotranspiration and flow routing among others. Further research and application on this model has been done, such as adapting other meso-scaled basins and adding erosion processes in the hydrological model. However, TACD model is computationally intensive. This has made it not efficient on large and well discretized river basins. Aswell, the current version is not compatible with latest PCRaster Version 4.1, which offers new capabilities on 64-bit hardware architecture, hydraulic calculation improvements, in maps creation, some error and bug fixes. The current work studied and adapted TACD model into the latest GIS PCRaster Version 4.1. This was done by editing the original scripts, replacing deprecated functionalities without losing correctness of the TACD model. The correctness of the adapted TACD model was verified by using the original study case of the Brugga Basin and comparing the adapted model results with the original model results by Stefan Roser in 2001. Small differences were found due to the fact that some hydraulic and hydrological routines were optimized since version 2 of GIS PCRaster. Therefore, the hydraulic and hydrological processes are well represented. With this new working model, further research and development on current topics like uncertainty analysis, GCM downscaling techniques and spatio-temporal modelling are encouraged.

Searching for the optimal drought index and timescale combination to detect drought: a case study from the lower Jinsha River basin, China

NASA Astrophysics Data System (ADS)

Fluixá-Sanmartín, Javier; Pan, Deng; Fischer, Luzia; Orlowsky, Boris; García-Hernández, Javier; Jordan, Frédéric; Haemmig, Christoph; Zhang, Fangwei; Xu, Jijun

2018-02-01

Drought indices based on precipitation are commonly used to identify and characterize droughts. Due to the general complexity of droughts, the comparison of index-identified events with droughts at different levels of the complete system, including soil humidity or river discharges, relies typically on model simulations of the latter, entailing potentially significant uncertainties. The present study explores the potential of using precipitation-based indices to reproduce observed droughts in the lower part of the Jinsha River basin (JRB), proposing an innovative approach for a catchment-wide drought detection and characterization. Two indicators, namely the Overall Drought Extension (ODE) and the Overall Drought Indicator (ODI), have been defined. These indicators aim at identifying and characterizing drought events on the basin scale, using results from four meteorological drought indices (standardized precipitation index, SPI; rainfall anomaly index, RAI; percent of normal precipitation, PN; deciles, DEC) calculated at different locations of the basin and for different timescales. Collected historical information on drought events is used to contrast results obtained with the indicators. This method has been successfully applied to the lower Jinsha River basin in China, a region prone to frequent and severe droughts. Historical drought events that occurred from 1960 to 2014 have been compiled and cataloged from different sources, in a challenging process. The analysis of the indicators shows a good agreement with the recorded historical drought events on the basin scale. It has been found that the timescale that best reproduces observed events across all the indices is the 6-month timescale.

Case study: design, operation, maintenance and water quality management of sustainable storm water ponds for roof runoff.

PubMed

Scholz, Miklas

2004-12-01

The purpose of this case study was to optimise design, operation and maintenance guidelines, and to assess the water treatment potential of a storm water pond system after 15 months of operation. The system was based on a combined silt trap, attenuation pond and vegetated infiltration basin. This combination was used as the basis for construction of a roof water runoff system from a single domestic property. United Kingdom Building Research Establishment and Construction Industry Research and Information Association, and German Association for Water, Wastewater and Waste design guidelines were tested. These design guidelines failed because they did not consider local conditions. The infiltration function for the infiltration basin was logarithmic. Algal control techniques were successfully applied, and treatment of rainwater runoff from roofs was found to be largely unnecessary for recycling (e.g., watering plants). However, seasonal and diurnal variations of biochemical oxygen demand, dissolved oxygen and pH were recorded.

Dynamics of thin-skinned fold and thrust belts with a tilted detachment

NASA Astrophysics Data System (ADS)

Fernandez, Naiara; Kaus, Boris J. P.; Epard, Jean-Luc

2014-05-01

The formation of the Jura fold and thrust belt is linked to the Alpine orogeny. However, it is still a matter of debate why the Jura was formed tens of kilometres far away from the active deformation front while the Molasse basin that lies in between remained mostly undeformed. Progressive thickening of the Molasse basin due to its infill with sediments, and the existence of a tilted potential detachment level at the Triassic evaporitic units, have been pushed forward as the main causes for the detachment of the Molasse basin and the consequent jump of the deformation front from the Alpine front to the position of the Jura at around 22 Ma or later (e.g Willett and Schlunegger, 2010). In order to better understand the dynamics of a thin-skinned fold and thrust belt with a tilted detachment we have performed systematic forward numerical simulations with the 2D thermo-mechanical finite element code MILAMIN_VEP. The modelled setup consists of a tilted detachment, overlain by a sedimentary cover of constant thickness and a wedge shaped basin infill that makes the initial surface slope of the system to be zero. In this study we have tested the importance of the following factors in the dynamics of such a fold and thrust belt evolution: 1) the applied boundary conditions 2) the angle of a uniformly tilted detachment 3) the end displacement of a curved detachment with a flexural foreland basin profile. The implications of the studied factors are discussed for the case of the Jura-Molasse system. Acknowledgements Funding was provided by the European Research Council under the European Community's Seventh Framework program (FP7/2007-2013) ERC Grant agreement #258830. References Willett, S.D. and Schlunegger, F. 2010, The last phase of deposition in the Swiss Molasse Basin: from foredeep to negative-alpha basin. Basin Research 22, 623-639, doi: 10.1111/j.1365-2117.2009.00435.x

Accounting for Rainfall Spatial Variability in Prediction of Flash Floods

NASA Astrophysics Data System (ADS)

Saharia, M.; Kirstetter, P. E.; Gourley, J. J.; Hong, Y.; Vergara, H. J.

2016-12-01

Flash floods are a particularly damaging natural hazard worldwide in terms of both fatalities and property damage. In the United States, the lack of a comprehensive database that catalogues information related to flash flood timing, location, causative rainfall, and basin geomorphology has hindered broad characterization studies. First a representative and long archive of more than 20,000 flooding events during 2002-2011 is used to analyze the spatial and temporal variability of flash floods. We also derive large number of spatially distributed geomorphological and climatological parameters such as basin area, mean annual precipitation, basin slope etc. to identify static basin characteristics that influence flood response. For the same period, the National Severe Storms Laboratory (NSSL) has produced a decadal archive of Multi-Radar/Multi-Sensor (MRMS) radar-only precipitation rates at 1-km spatial resolution with 5-min temporal resolution. This provides an unprecedented opportunity to analyze the impact of event-level precipitation variability on flooding using a big data approach. To analyze the impact of sub-basin scale rainfall spatial variability on flooding, certain indices such as the first and second scaled moment of rainfall, horizontal gap, vertical gap etc. are computed from the MRMS dataset. Finally, flooding characteristics such as rise time, lag time, and peak discharge are linked to derived geomorphologic, climatologic, and rainfall indices to identify basin characteristics that drive flash floods. Next the model is used to predict flash flooding characteristics all over the continental U.S., specifically over regions poorly covered by hydrological observations. So far studies involving rainfall variability indices have only been performed on a case study basis, and a large scale approach is expected to provide a deeper insight into how sub-basin scale precipitation variability affects flooding. Finally, these findings are validated using the National Weather Service storm reports and a historical flood fatalities database. This analysis framework will serve as a baseline for evaluating distributed hydrologic model simulations such as the Flooded Locations And Simulated Hydrographs Project (FLASH) (http://flash.ou.edu).

Effects of anthropogenic groundwater exploitation on land surface processes: A case study of the Haihe River Basin, northern China

NASA Astrophysics Data System (ADS)

Zou, Jing; Xie, Zhenghui; Zhan, Chesheng; Qin, Peihua; Sun, Qin; Jia, Binghao; Xia, Jun

2015-05-01

In this study, we incorporated a groundwater exploitation scheme into the land surface model CLM3.5 to investigate the effects of the anthropogenic exploitation of groundwater on land surface processes in a river basin. Simulations of the Haihe River Basin in northern China were conducted for the years 1965-2000 using the model. A control simulation without exploitation and three exploitation simulations with different water demands derived from socioeconomic data related to the Basin were conducted. The results showed that groundwater exploitation for human activities resulted in increased wetting and cooling effects at the land surface and reduced groundwater storage. A lowering of the groundwater table, increased upper soil moisture, reduced 2 m air temperature, and enhanced latent heat flux were detected by the end of the simulated period, and the changes at the land surface were related linearly to the water demands. To determine the possible responses of the land surface processes in extreme cases (i.e., in which the exploitation process either continued or ceased), additional hypothetical simulations for the coming 200 years with constant climate forcing were conducted, regardless of changes in climate. The simulations revealed that the local groundwater storage on the plains could not contend with high-intensity exploitation for long if the exploitation process continues at the current rate. Changes attributable to groundwater exploitation reached extreme values and then weakened within decades with the depletion of groundwater resources and the exploitation process will therefore cease. However, if exploitation is stopped completely to allow groundwater to recover, drying and warming effects, such as increased temperature, reduced soil moisture, and reduced total runoff, would occur in the Basin within the early decades of the simulation period. The effects of exploitation will then gradually disappear, and the variables will approach the natural state and stabilize at different rates. Simulations were also conducted for cases in which exploitation either continues or ceases using future climate scenario outputs from a general circulation model. The resulting trends were almost the same as those of the simulations with constant climate forcing, despite differences in the climate data input. Therefore, a balance between slow groundwater restoration and rapid human development of the land must be achieved to maintain a sustainable water resource.

Recharge and Groundwater Flow Within an Intracratonic Basin, Midwestern United States.

PubMed

Panno, Samuel V; Askari, Zohreh; Kelly, Walton R; Parris, Thomas M; Hackley, Keith C

2018-01-01

The conservative nature of chloride (Cl - ) in groundwater and the abundance of geochemical data from various sources (both published and unpublished) provided a means of developing, for the first time, a representation of the hydrogeology of the Illinois Basin on a basin-wide scale. The creation of Cl - isocons superimposed on plan view maps of selected formations and on cross sections across the Illinois Basin yielded a conceptual model on a basin-wide scale of recharge into, groundwater flow within and through the Illinois Basin. The maps and cross sections reveal the infiltration and movement of freshwater into the basin and dilution of brines within various geologic strata occurring at basin margins and along geologic structures. Cross-formational movement of brines is also seen in the northern part of the basin. The maps and cross sections also show barriers to groundwater movement created by aquitards resulting in areas of apparent isolation/stagnation of concentrated brines within the basin. The distribution of Cl - within the Illinois Basin suggests that the current chemical composition of groundwater and distribution of brines within the basin is dependent on five parameters: (1) presence of bedrock exposures along basin margins; (2) permeability of geologic strata and their distribution relative to one another; (3) presence or absence of major geologic structures; (4) intersection of major waterways with geologic structures, basin margins, and permeable bedrock exposures; and (5) isolation of brines within the basin due to aquitards, inhomogeneous permeability, and, in the case of the deepest part of the basin, brine density effects. © 2017, National Ground Water Association.

Comparison between flood prone areas' geomorphic features in the Abruzzo region

NASA Astrophysics Data System (ADS)

Orlando, D.; Giglioni, M.; Magnaldi, S.

2017-07-01

Flood risk maps are one of the main non-structural measures for risk mitigation, but, as the risk knowledge degree is directly proportional to the community interest and financial capability, many sites are devoid of flood inundation areas studies. Recently many authors have investigated the capability of flood prone areas individuation with geomorphological DIGITAL ELEVATION MODEL(DEM) based approaches. These approaches highlight the role of geomorphic features derived from DEM, in this case slope, curvature, elevation, and topographic wetness index, to preliminary inundated areas' identification, without using hydraulic simulations. The present studies aim to analyze the geomorphic features of different hazard levels that lie under the identified inundated areas that have been carried out by the Abruzzo Region Basin Authority. The Aterno-Pescara and Foro river basins have been investigated. The results show that the characteristics of the flooded areas can be clearly distinguished from those of the entire basin,however, the difficultly of geomorphic features in individuatingthe areas of different hazard classifications is obvious.

Understanding the relative role of dispersion mechanisms across basin scales

NASA Astrophysics Data System (ADS)

Di Lazzaro, M.; Zarlenga, A.; Volpi, E.

2016-05-01

Different mechanisms are understood to represent the primary sources of the variance of travel time distribution in natural catchments. To quantify the fraction of variance introduced by each component, dispersion coefficients have been earlier defined in the framework of geomorphology-based rainfall-runoff models. In this paper we compare over a wide range of basin sizes and for a variety of runoff conditions the relative role of geomorphological dispersion, related to the heterogeneity of path lengths, and hillslope kinematic dispersion, generated by flow processes within the hillslopes. Unlike previous works, our approach does not focus on a specific study case; instead, we try to generalize results already obtained in previous literature stemming from the definition of a few significant parameters related to the metrics of the catchment and flow dynamics. We further extend this conceptual framework considering the effects of two additional variance-producing processes: the first covers the random variability of hillslope velocities (i.e. of travel times over hillslopes); the second deals with non-uniform production of runoff over the basin (specifically related to drainage density). Results are useful to clarify the role of hillslope kinematic dispersion and define under which conditions it counteracts or reinforces geomorphological dispersion. We show how its sign is ruled by the specific spatial distribution of hillslope lengths within the basin, as well as by flow conditions. Interestingly, while negative in a wide range of cases, kinematic dispersion is expected to become invariantly positive when the variability of hillslope velocity is large.

Sustainability or Collapse: Interplay Between Decadal Climate Variability and Human Activities Matters

NASA Astrophysics Data System (ADS)

Lu, Y.; Hu, H.; Tian, F.

2016-12-01

The Aral Sea Crisis and the deterioration of Tarim River Basin are representative cases of emergent water deficit problems in arid areas. Comparing cases of water deficit problems in different regions and considering the in the perspective of socio-hydrology is helpful to obtain guidance on integrated management of arid area basins. Analyzing the interplay between decadal climate variability and human activities in both basins, the important role of human activities is observed. Decadal climate variability tempts people to adapt fast to increasing water resources and slowly to decreasing water resources, while using unsustainable technical measures to offset water shortage. Due to this asymmetry the situation deteriorates with technically enhanced capabilities of societies to exploit water resources, and more integrated long-term management capacity is in high demand.

Prediction of monthly regional groundwater levels through hybrid soft-computing techniques

NASA Astrophysics Data System (ADS)

Chang, Fi-John; Chang, Li-Chiu; Huang, Chien-Wei; Kao, I.-Feng

2016-10-01

Groundwater systems are intrinsically heterogeneous with dynamic temporal-spatial patterns, which cause great difficulty in quantifying their complex processes, while reliable predictions of regional groundwater levels are commonly needed for managing water resources to ensure proper service of water demands within a region. In this study, we proposed a novel and flexible soft-computing technique that could effectively extract the complex high-dimensional input-output patterns of basin-wide groundwater-aquifer systems in an adaptive manner. The soft-computing models combined the Self Organized Map (SOM) and the Nonlinear Autoregressive with Exogenous Inputs (NARX) network for predicting monthly regional groundwater levels based on hydrologic forcing data. The SOM could effectively classify the temporal-spatial patterns of regional groundwater levels, the NARX could accurately predict the mean of regional groundwater levels for adjusting the selected SOM, the Kriging was used to interpolate the predictions of the adjusted SOM into finer grids of locations, and consequently the prediction of a monthly regional groundwater level map could be obtained. The Zhuoshui River basin in Taiwan was the study case, and its monthly data sets collected from 203 groundwater stations, 32 rainfall stations and 6 flow stations during 2000 and 2013 were used for modelling purpose. The results demonstrated that the hybrid SOM-NARX model could reliably and suitably predict monthly basin-wide groundwater levels with high correlations (R2 > 0.9 in both training and testing cases). The proposed methodology presents a milestone in modelling regional environmental issues and offers an insightful and promising way to predict monthly basin-wide groundwater levels, which is beneficial to authorities for sustainable water resources management.

Assessing the usefulness of the water poverty index by applying it to a special case: Can one be water poor with high levels of access?

NASA Astrophysics Data System (ADS)

Komnenic, V.; Ahlers, R.; Zaag, P. van der

Using indices and indicators in assessment of progress of a developing country has two sides. Such indicators offer an easy-to-understand shorthand/synopsis of issues vital for a country’s development. The other side of the coin, however, is that this synopsis may be distorted due to incorrect data or inapplicability of an index or an indicator to a specific case. This paper assesses the applicability of Water Poverty Index for the countries riparian to the Sava sub-basin, a tributary to the Danube river basin and presents the results of its application. At the same time, the paper discusses the concept of water poverty and the appropriateness of its use in the case of Sava River Basin countries by differentiating the economic poverty in some of those countries from sufficient access to and use of water resources in all of them.

Impact of land-use and climatic changes on hydrology of the Himalayan Basin: A case study of the Kosi Basin

NASA Astrophysics Data System (ADS)

Sharma, Keshav Prasad

1997-10-01

Land-use and climatic changes are of major concern in the Himalayan region because of their potential impacts on a predominantly agriculture-based economy and a regional hydrology dominated by strong seasonality. Such concerns are not limited to any particular basin but exist throughout the region including the downstream plain areas. As a representative basin of the Himalayas, we studied the Kosi basin (54,000 km2) located in the mountainous area of the central Himalayan region. We analyzed climatic and hydrologic information to assess the impacts of existing and potential future land-use and climatic changes over the basin. The assessment of anthropogenic inputs showed that the population grew at a compound growth rate of about one percent per annum over the basin during the last four decades. The comparison of land-use data based on the surveys made in the 1960s, and the surveys of 1978-79 did not reveal noticeable trends in land-use change. Analysis of meteorological and hydrological trends using parametric and nonparametric statistics for monthly data from 1947 to 1993 showed some increasing tendency for temperature and precipitation. Statistical tests of hydrological trends indicated an overall decrease of discharge along mainstem Kosi River and its major tributaries. The decreasing trends of streamflow were more significant during low-flow months. Statistical analysis of homogeneity showed that the climatological as well as the hydrological trends were more localized in nature lacking distinct basinwide significance. Statistical analysis of annual sediment time series, available for a single station on the Kosi River did not reveal a significant trend. We used water balance, statistical correlation, and distributed deterministic modeling approaches to analyze the hydrological sensitivity of the basin to possible land-use and climatic changes. The results indicated a stronger influence of basin characteristics compared to climatic characteristics on flow regime. Among the climatic variables, hydrologic response was much more sensitive to changes in precipitation, and the response was more significant in the drier areas of the basin. Rapid retreat of glaciers due to potential global warming was shown to be as important as projected deforestation scenarios in regulating sediment flux over the basin.

Spatio-temporal optimization of agricultural practices to achieve a sustainable development at basin level; framework of a case study in Colombia

NASA Astrophysics Data System (ADS)

Uribe, Natalia; corzo, Gerald; Solomatine, Dimitri

2016-04-01

The flood events present during the last years in different basins of the Colombian territory have raised questions on the sensitivity of the regions and if this regions have common features. From previous studies it seems important features in the sensitivity of the flood process were: land cover change, precipitation anomalies and these related to impacts of agriculture management and water management deficiencies, among others. A significant government investment in the outreach activities for adopting and promoting the Colombia National Action Plan on Climate Change (NAPCC) is being carried out in different sectors and regions, having as a priority the agriculture sector. However, more information is still needed in the local environment in order to assess were the regions have this sensitivity. Also the continuous change in one region with seasonal agricultural practices have been pointed out as a critical information for optimal sustainable development. This combined spatio-temporal dynamics of crops cycle in relation to climate change (or variations) has an important impact on flooding events at basin areas. This research will develop on the assessment and optimization of the aggregated impact of flood events due to determinate the spatio-temporal dynamic of changes in agricultural management practices. A number of common best agricultural practices have been identified to explore their effect in a spatial hydrological model that will evaluate overall changes. The optimization process consists on the evaluation of best performance in the agricultural production, without having to change crops activities or move to other regions. To achieve this objectives a deep analysis of different models combined with current and future climate scenarios have been planned. An algorithm have been formulated to cover the parametric updates such that the optimal temporal identification will be evaluated in different region on the case study area. Different hydroinformatics techniques for optimization and uncertainty analysis are included in a framework that will solve partially the computational load found in the pre-runs of the case study. The work will focus on the region Fuquene basin in Colombia but this will not limit the scope of this study to have general methodological applications to other areas. Key words Modelling, WFlow_sbm, agriculture practices, climate change, optimization, flooding, spatial and temporal analysis

The role of seasonal water scarcity on water quality: a global analysis with case study in the Magdalena, Colombia

NASA Astrophysics Data System (ADS)

Burke, Sophia; Mulligan, Mark

2017-04-01

Water scarcity is not just a problem of its own right (hydrological drought) but cascades the hydro-economic system to create problems for crop growth and livestock (agricultural drought) and thus for wellbeing and economic productivity (economic drought). One of these cascades is the impact of reduced water quantity on water quality as a result of non-point source pollutant concentration in water bodies such as rivers, lakes and wetlands. This paper investigates the impact of seasonal water shortages on the quality of supplied water to urban centres with a view to better understanding how land use management can reduce dry-season pollutant spikes. We apply a widely used spatial hydrological model (WaterWorld) and its water quality index (the human footprint on water quality, HFWQ) to examine to what extent HFWQ of water flowing into urban water intakes is affected by flow seasonality and by typical "dry year" events. A global analysis shows trends across climatic and land use gradients and is followed by a regional analysis of the Magdalena basin in Colombia: a large basin with 79% of the countries population and a mixture of intensively farmed and protected lands along a seasonality gradient from South to North. The Magdalena is a case study basin of the EartH2Observe project.

Integrated regional assessment of global climatic change: lessons from the Mackenzie Basin Impact Study (MBIS)

NASA Astrophysics Data System (ADS)

Cohen, Stewart J.

1996-04-01

This paper outlines the potential role integrated regional assessments of global climatic change scenarios could play in building better links between science and related policy concerns. The concept is illustrated through description of an ongoing case study from Canada—the Mackenzie Basin Impact Study (MBIS). As part of the Government of Canada's Green Plan, the Global Warming Science Program includes a study of regional impacts of global warming scenarios in the Mackenzie Basin, located in northwestern Canada. The MBIS is a six-year program focussing on potential climate-induced changes in the land and water resource base, and the implications of four scenarios of global climatic change on land use and economic policies in this region. These policy issues include interjurisdictional water management, sustainability of native lifestyles, economic development opportunities (agriculture, forestry, tourism, etc.), sustainability of ecosystems and infrastructure maintenance. MBIS is due to be completed in 1997. MBIS represents an attempt to address regional impacts by incorporating a "family of integrators" into the study framework, and by directly involving stakeholders in planning and research activities. The experience in organizing and carrying out this project may provide some lessons for others interested in organizing regional or country studies.

FIELD TESTS OF GEOGRAPHICALLY-DEPENDENT VS. THRESHOLD-BASED WATERSHED CLASSIFICATION SCHEMES IN THE GREAT LAKES BASIN

EPA Science Inventory

We compared classification schemes based on watershed storage (wetland + lake area/watershed area) and forest fragmentation with a geographically-based classification scheme for two case studies involving 1) Lake Superior tributaries and 2) watersheds of riverine coastal wetlands...

HYDROGEOLOGIC SETTING AND CHARACTERISTICS OF RIPARIAN MEADOW COMPLEXES IN THE MOUNTAINS OF CENTRAL NEVADA: A CASE STUDY

EPA Science Inventory

Riparian wet meadow complexes in the mountains of the central Great Basin are scarce, ecologically important systems threatened by stream incision. An interdisciplinary team from government and academia is investigating the origin, setting, and biological--physical interrelations...

Eco-Efficiency Analysis of Green Infrastructure Based Watershed Management: A Case Study of Raionwater Harvesting in the Albemarle-Pimlico Basins

EPA Science Inventory

Rising world population, rapid urbanization, and land development exacerbate the global challenge of protecting watersheds and their sustainability. The U.S. Environmental Protection Agency (EPA) has achieved significant progress in protecting and remediating national watersheds,...

FIELD TESTS OF GEOGRAPHICALLY-DEPENDENT VS. THRESHOLD-BASED WATERSHED CLASSIFICATION SCHEMED IN THE GREAT LAKES BASIN

EPA Science Inventory

We compared classification schemes based on watershed storage (wetland + lake area/watershed area) and forest fragmentation with a geographically-based classification scheme for two case studies involving 1)Lake Superior tributaries and 2) watersheds of riverine coastal wetlands ...

Impact of mineralization on carbon dioxide migration in term of critical value of fault permeability.

NASA Astrophysics Data System (ADS)

Alshammari, A.; Brantley, D.; Knapp, C. C.; Lakshmi, V.

2017-12-01

In this study, multi chemical components ((H2O, H2S) will be injected with supercritical carbon dioxide in onshore part of South Georgia Rift (SGR) Basin model. Chemical reaction expected issue between these components to produce stable mineral of carbonite rocks by the time. The 3D geological model has been extracted from petrel software and computer modelling group (CMG) package software has been used to build simulation model explain the effect of mineralization on fault permeability that control on plume migration critically between (0-0.05 m Darcy). The expected results will be correlated with single component case (CO2 only) to evaluate the importance the mineralization on CO2 plume migration in structure and stratigraphic traps and detect the variation of fault leakage in case of critical values (low permeability). The results will also, show us the ratio of every trapped phase in (SGR) basin reservoir model.

Sharing the cost of river basin adaptation portfolios to climate change: Insights from social justice and cooperative game theory

NASA Astrophysics Data System (ADS)

Girard, Corentin; Rinaudo, Jean-Daniel; Pulido-Velazquez, Manuel

2016-10-01

The adaptation of water resource systems to the potential impacts of climate change requires mixed portfolios of supply and demand adaptation measures. The issue is not only to select efficient, robust, and flexible adaptation portfolios but also to find equitable strategies of cost allocation among the stakeholders. Our work addresses such cost allocation problems by applying two different theoretical approaches: social justice and cooperative game theory in a real case study. First of all, a cost-effective portfolio of adaptation measures at the basin scale is selected using a least-cost optimization model. Cost allocation solutions are then defined based on economic rationality concepts from cooperative game theory (the Core). Second, interviews are conducted to characterize stakeholders' perceptions of social justice principles associated with the definition of alternatives cost allocation rules. The comparison of the cost allocation scenarios leads to contrasted insights in order to inform the decision-making process at the river basin scale and potentially reap the efficiency gains from cooperation in the design of river basin adaptation portfolios.

Pesticides in the rivers and streams of two river basins in northern Greece.

PubMed

Papadakis, Emmanouil-Nikolaos; Tsaboula, Aggeliki; Vryzas, Zisis; Kotopoulou, Athina; Kintzikoglou, Katerina; Papadopoulou-Mourkidou, Euphemia

2018-05-15

The pollution caused by pesticides, and their ecotoxicological implications were investigated in water samples from the Strymonas and Nestos river basins (Northern Greece). Chlorpyrifos was the most frequently detected pesticide in both basins (42 and 37% in the Strymonas and Nestos basins, respectively), followed by fluometuron and terbuthylazine (25 and 12%, Strymonas), and bentazone and boscalid (24 and 10%, Nestos). The Annual Average and the Maximum Allowable Concentration of Environmental Quality Standards set in European Union Directives were exceeded in several cases by alphamethrin and chlorpyrifos. Risk Quotient assessment revealed significant ecological risk towards the aquatic organisms in over 20% of the water samples. Insecticides (mostly pyrethroids and organophosphosphates) contributed more in the ecotoxicological risk than herbicides and fungicides. The three main rivers in the current study (Strymonas, Aggitis, Nestos) exhibited similar sum of RQs indicating that aquatic life in all three of them was at the same risk level. However, the sums of RQs were higher in the various streams monitored than the three rivers. Copyright © 2017 Elsevier B.V. All rights reserved.

[Variation characteristics and influencing factors of actual evapotranspiration under various vegetation types: A case study in the Huaihe River Basin, China.

PubMed

Wu, Rong Jun; Xing, Xiao Yong

2016-06-01

The actual evapotranspiration was modelled utilizing the boreal ecosystem productivity simulator (BEPS) in Huaihe River Basin from 2001 to 2012. In the meantime, the quantitative analyses of the spatial-temporal variations of actual evapotranspiration characteristics and its influencing factors under different vegetation types were conducted. The results showed that annual evapotranspiration gradually decreased from southeast to northwest, tended to increase annually, and the monthly change for the average annual evapotranspiration was double-peak curve. The differences of evapotranspiration among vegetation types showed that the farmland was the largest contributor for the evapotranspiration of Huaihe Basin. The annual actual evapotranspiration of the mixed forest per unit area was the largest, and that of the bare ground per unit area was the smallest. The changed average annual evapotranspiration per unit area for various vegetation types indicated an increased tendency other than the bare ground, with a most significant increase trend for the evergreen broadleaf forest. The thermodynamic factors (such as average temperature) were the dominant factors affecting the actual evapotranspiration in the Huaihe Basin, followed by radiation and moisture factors.

Proceedings of the Klamath Basin Science Conference, Medford, Oregon, February 1-5, 2010

USGS Publications Warehouse

Thorsteinson, Lyman; VanderKooi, Scott; Duffy, Walter

2011-01-01

This report presents the proceedings of the Klamath Basin Science Conference (February 2010). A primary purpose of the meeting was to inform and update Klamath Basin stakeholders about areas of scientific progress and accomplishment during the last 5 years. Secondary conference objectives focused on the identification of outstanding information needs and science priorities as they relate to whole watershed management, restoration ecology, and possible reintroduction of Pacific salmon associated with the Klamath Basin Restoration Agreement (KBRA). Information presented in plenary, technical, breakout, and poster sessions has been assembled into chapters that reflect the organization, major themes, and content of the conference. Chapter 1 reviews the major environmental issues and resource management and other stakeholder needs of the basin. Importantly, this assessment of information needs included the possibility of large-scale restoration projects in the future and lessons learned from a case study in South Florida. Other chapters (2-6) summarize information about key components of the Klamath Basin, support conceptual modeling of the aquatic ecosystem (Chapter 7), and synthesize our impressions of the most pressing science priorities for management and restoration. A wealth of information was presented at the conference and this has been captured in chapters addressing environmental setting and human development of the basin, hydrology, watershed processes, fishery resources, and potential effects from climate change. The final chapter (8) culminates in a discussion of many specific research priorities that relate to and bookend the broader management needs and restoration goals identified in Chapter 1. In many instances, the conferees emphasized long-term and process-oriented approaches to watershed science in the basin as planning moves forward.

Post-Paleogene (post-Middle Eocene-pre-Miocene) Geodynamic evolution of the Upper Cretaceous-Paleogene Basins in Central Anatolia, Turkey

NASA Astrophysics Data System (ADS)

Rojay, Bora

2017-04-01

Central Anatolia is one of the key areas on the evolution of Cretaceous-Paleogene Tethys where stratigraphy of the region is well studied. However not well linked with tectonics. The so-called "Ankara Mélange" belt (AOM) and the basins on top are important elements in the understanding of the İzmir-Ankara-Erzincan suture belt (İAES) evolution in Anatolia (Turkey) and in the evolution of Tethys in minor Asia (Turkey). Some of the basins are directly situated on top of the tectonic slices of the accretionary prism (IAES). However, some are not tectonically well explained as in the case of Haymana basin. The southern continental fragments (eg. Kütahya-Bolkardaǧ and Kırşehir blocks from Gondwana) are approaching to northern continents (Pontides of Lauriasia) where basins like Haymana, Alçı, Kırıkkale and Orhaniye extensional basins are evolved in between the closing margins of two continents. Haymana basin is an extensional basin developed under contractional regime on top of both northward subducting oceanic fragments and an approaching fragments of southern continents. Paleogene (end of Eocene) is the time where the Seas were retreated to S-SE Anatolia leaving a continental setting in Anatolia during Oligocene-Miocene. The slip data gathered from the faults cross-cutting the Paleogene Units and the fabric from Cretaceous mélanges depicts a NNW-SSE to NNE-SSW compressional stress regime operated during post-Eocene-pre-Miocene period. Lately the slip surfaces were overprinted by post-Pliocene normal faulting. Key words: fault slip data, Paleogene, NNW-SSE compression, Anatolia.

Representing Geospatial Environment Observation Capability Information: A Case Study of Managing Flood Monitoring Sensors in the Jinsha River Basin

PubMed Central

Hu, Chuli; Guan, Qingfeng; Li, Jie; Wang, Ke; Chen, Nengcheng

2016-01-01

Sensor inquirers cannot understand comprehensive or accurate observation capability information because current observation capability modeling does not consider the union of multiple sensors nor the effect of geospatial environmental features on the observation capability of sensors. These limitations result in a failure to discover credible sensors or plan for their collaboration for environmental monitoring. The Geospatial Environmental Observation Capability (GEOC) is proposed in this study and can be used as an information basis for the reliable discovery and collaborative planning of multiple environmental sensors. A field-based GEOC (GEOCF) information representation model is built. Quintuple GEOCF feature components and two GEOCF operations are formulated based on the geospatial field conceptual framework. The proposed GEOCF markup language is used to formalize the proposed GEOCF. A prototype system called GEOCapabilityManager is developed, and a case study is conducted for flood observation in the lower reaches of the Jinsha River Basin. The applicability of the GEOCF is verified through the reliable discovery of flood monitoring sensors and planning for the collaboration of these sensors. PMID:27999247

Representing Geospatial Environment Observation Capability Information: A Case Study of Managing Flood Monitoring Sensors in the Jinsha River Basin.

PubMed

Hu, Chuli; Guan, Qingfeng; Li, Jie; Wang, Ke; Chen, Nengcheng

2016-12-16

Sensor inquirers cannot understand comprehensive or accurate observation capability information because current observation capability modeling does not consider the union of multiple sensors nor the effect of geospatial environmental features on the observation capability of sensors. These limitations result in a failure to discover credible sensors or plan for their collaboration for environmental monitoring. The Geospatial Environmental Observation Capability (GEOC) is proposed in this study and can be used as an information basis for the reliable discovery and collaborative planning of multiple environmental sensors. A field-based GEOC (GEOCF) information representation model is built. Quintuple GEOCF feature components and two GEOCF operations are formulated based on the geospatial field conceptual framework. The proposed GEOCF markup language is used to formalize the proposed GEOCF. A prototype system called GEOCapabilityManager is developed, and a case study is conducted for flood observation in the lower reaches of the Jinsha River Basin. The applicability of the GEOCF is verified through the reliable discovery of flood monitoring sensors and planning for the collaboration of these sensors.

Governance of water resources in the phase of change: a case study of the implementation of the EU Water Framework Directive in Sweden.

PubMed

Hammer, Monica; Balfors, Berit; Mörtberg, Ulla; Petersson, Mona; Quin, Andrew

2011-03-01

In this article, focusing on the ongoing implementation of the EU Water Framework Directive, we analyze some of the opportunities and challenges for a sustainable governance of water resources from an ecosystem management perspective. In the face of uncertainty and change, the ecosystem approach as a holistic and integrated management framework is increasingly recognized. The ongoing implementation of the Water Framework Directive (WFD) could be viewed as a reorganization phase in the process of change in institutional arrangements and ecosystems. In this case study from the Northern Baltic Sea River Basin District, Sweden, we focus in particular on data and information management from a multi-level governance perspective from the local stakeholder to the River Basin level. We apply a document analysis, hydrological mapping, and GIS models to analyze some of the institutional framework created for the implementation of the WFD. The study underlines the importance of institutional arrangements that can handle variability of local situations and trade-offs between solutions and priorities on different hierarchical levels.

Geometry and subsidence history of the Dead Sea basin: A case for fluid-induced mid-crustal shear zone?

USGS Publications Warehouse

ten Brink, Uri S.; Flores, C.H.

2012-01-01

Pull-apart basins are narrow zones of crustal extension bounded by strike-slip faults that can serve as analogs to the early stages of crustal rifting. We use seismic tomography, 2-D ray tracing, gravity modeling, and subsidence analysis to study crustal extension of the Dead Sea basin (DSB), a large and long-lived pull-apart basin along the Dead Sea transform (DST). The basin gradually shallows southward for 50 km from the only significant transverse normal fault. Stratigraphic relationships there indicate basin elongation with time. The basin is deepest (8-8.5 km) and widest (???15 km) under the Lisan about 40 km north of the transverse fault. Farther north, basin depth is ambiguous, but is 3 km deep immediately north of the lake. The underlying pre-basin sedimentary layer thickens gradually from 2 to 3 km under the southern edge of the DSB to 3-4 km under the northern end of the lake and 5-6 km farther north. Crystalline basement is ???11 km deep under the deepest part of the basin. The upper crust under the basin has lower P wave velocity than in the surrounding regions, which is interpreted to reflect elevated pore fluids there. Within data resolution, the lower crust below ???18 km and the Moho are not affected by basin development. The subsidence rate was several hundreds of m/m.y. since the development of the DST ???17 Ma, similar to other basins along the DST, but subsidence rate has accelerated by an order of magnitude during the Pleistocene, which allowed the accumulation of 4 km of sediment. We propose that the rapid subsidence and perhaps elongation of the DSB are due to the development of inter-connected mid-crustal ductile shear zones caused by alteration of feldspar to muscovite in the presence of pore fluids. This alteration resulted in a significant strength decrease and viscous creep. We propose a similar cause to the enigmatic rapid subsidence of the North Sea at the onset the North Atlantic mantle plume. Thus, we propose that aqueous fluid flux into a slowly extending continental crust can cause rapid basin subsidence that may be erroneously interpreted as an increased rate of tectonic activity. Copyright 2012 by the American Geophysical Union.

19 CFR 10.222 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-04-01

... ARTICLES CONDITIONALLY FREE, SUBJECT TO A REDUCED RATE, ETC. United States-Caribbean Basin Trade..., coin purses, coin holders, compacts, currency cases, key cases, letter cases, license cases, money.... “NAFTA” means the North American Free Trade Agreement entered into by the United States, Canada, and...

19 CFR 10.222 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-04-01

... ARTICLES CONDITIONALLY FREE, SUBJECT TO A REDUCED RATE, ETC. United States-Caribbean Basin Trade..., coin purses, coin holders, compacts, currency cases, key cases, letter cases, license cases, money.... “NAFTA” means the North American Free Trade Agreement entered into by the United States, Canada, and...

Modeling the hydrologic effects of land and water development interventions: a case study of the upper Blue Nile river basin

NASA Astrophysics Data System (ADS)

Haregeweyn, Nigussie; Tsunekawa, Atsushi; Tsubo, Mitsuru; Meshesha, Derege; Adgo, Enyew; Poesen, Jean; Schütt, Brigitta

2014-05-01

Over 67% of the Ethiopian landmass has been identified as very vulnerable to climate variability and land degradation. These problems are more prevalent in the Upper Blue Nile (UBN, often called Abay) river basin covering a drainage area of about 199,800 km2. The UBN River runs from Lake Tana (NW Ethiopia) to the Ethiopia-Sudan border. To enhance the adaptive capacity to the high climate variability and land degradation in the basin, different land and water management measures (stone/soil bunds, runoff collector trenches, exclosures) have been extensively implemented, especially since recent years. Moreover, multipurpose water harvesting schemes including the Grand Ethiopian Renaissance Dam (GERD, reservoir area of ca. 4000 km2) and 17 other similar projects are being or to be implemented by 2025. However, impact studies on land and water management aspects rarely include detailed hydrological components especially at river basin scale, although it is generally regarded as a major determinant of hydrological processes. The main aim of this study is therefore to model the significance of land and water management interventions in surface runoff response at scale of UBN river basin and to suggest some recommendations. Spatially-distributed annual surface runoff was simulated for both present-day and future (2025) land and water management conditions using calibrated values of the proportional loss model in ArcGIS environment. Average annual rainfall map (1998-2012) was produced from calibrated TRMM satellite source and shows high spatial variability of rainfall ranging between ca. 1000 mm in the Eastern part of the basin to ca. 2000 mm in the southern part of the basin. Present-day land use day condition was obtained from Abay Basin Master Plan study. The future land use map was created taking into account the land and water development interventions to be implemented by 2025. Under present-day conditions, high spatial variability of annual runoff depth was observed in the basin ranging from 80 mm in the central part of the basin to over 1700 mm in water bodies. This variation is mainly controlled by variation in surface conditions and areal-extent of each land use type, and rainfall depth. For a specific land use type, runoff depth is found to increase with elevation as this in turn directly influences the rainfall distribution. By 2025, due to the land and water management interventions, total runoff depth in the basin could decrease by up to 40%. Following the conversion of other land use types to water bodies due to the medium to large-scale water harvesting schemes such as GERD reservoir, runoff response in those specific parts of the basin could increase by over 200%. Sub-basins have been prioritized for future land and water management interventions. Further study remains necessary to understand the downstream impacts of those interventions on runoff and sediment discharges. Keywords: Land and water management; Upper Blue Nile; Grand Ethiopian Renaissance Dam; Spatial variability of runoff; Downstream impact.

From the Mountains of the Moon to the Grand Renaissance: misinformation, disinformation and, finally, information for cooperation in the Nile River basin

NASA Astrophysics Data System (ADS)

Zaitchik, B. F.; Habib, S.; Anderson, M. C.; Ozdogan, M.

2012-12-01

The Nile River basin is shared by 11 nations and approximately 200 million people. Eight of the riparian States are defined as Least Developed Countries by the United Nations, and about 50% of the total basin population lives below the international poverty line. In addition, eight of the eleven countries have experienced internal or external wars in the past 20 years, six are predicted to be water scarce by 2025, and, at present, major water resource development projects are moving forward in the absence of a fully recognized basin-wide water sharing agreement. Nevertheless, the Nile basin presents remarkable opportunities for transboundary water cooperation, and today—notwithstanding significant substantive and perceived disagreements between stakeholders in the basin—this cooperation is beginning to be realized in topics ranging from flood early warning to hydropower optimization to regional food security. This presentation will provide an overview of historic and present challenges and opportunities for transboundary water management in the Nile basin and will present several case studies in which improved hydroclimatic information and communication systems are currently laying the groundwork for advanced cooperation. In this context climate change acts as both stress and motivator. On one hand, non-stationary hydrology is expected to tax water resources in the basin, and it undermines confidence in conventionally formulated water sharing agreements. On the other, non-stationarity is increasingly understood to be an exogenous threat to regional food and water security that will require informed, flexible cooperation between riparian states.

Alaska OCS socioeconomic studies program: St. George basin petroleum development scenarios, Anchorage impact analysis. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ender, R.L.; Gorski, S.

1981-10-01

The report consists of an update to the Anchorage socioeconomic and physical baseline and infrastructure standards used to forecast impacts with and without OCS oil and gas development in Alaska. This material is found in Technical Report 43, Volumes 1 and 2 entitled 'Gulf of Alaska and Lower Cook Inlet Petroleum Development Scenarios, Anchorage Socioeconomic and Physical Baseline and Anchorage Impact Analysis.' These updates should be read in conjunction with the above report. In addition, the Anchorage base case and petroleum development scenarios for the St. George Basin are given. These sections are written to stand alone without reference.

A Safety Case Approach for Deep Geologic Disposal of DOE HLW and DOE SNF in Bedded Salt - 13350

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sevougian, S. David; MacKinnon, Robert J.; Leigh, Christi D.

2013-07-01

The primary objective of this study is to investigate the feasibility and utility of developing a defensible safety case for disposal of United States Department of Energy (U.S. DOE) high-level waste (HLW) and DOE spent nuclear fuel (SNF) in a conceptual deep geologic repository that is assumed to be located in a bedded salt formation of the Delaware Basin [1]. A safety case is a formal compilation of evidence, analyses, and arguments that substantiate and demonstrate the safety of a proposed or conceptual repository. We conclude that a strong initial safety case for potential licensing can be readily compiled bymore » capitalizing on the extensive technical basis that exists from prior work on the Waste Isolation Pilot Plant (WIPP), other U.S. repository development programs, and the work published through international efforts in salt repository programs such as in Germany. The potential benefits of developing a safety case include leveraging previous investments in WIPP to reduce future new repository costs, enhancing the ability to effectively plan for a repository and its licensing, and possibly expediting a schedule for a repository. A safety case will provide the necessary structure for organizing and synthesizing existing salt repository science and identifying any issues and gaps pertaining to safe disposal of DOE HLW and DOE SNF in bedded salt. The safety case synthesis will help DOE to plan its future R and D activities for investigating salt disposal using a risk-informed approach that prioritizes test activities that include laboratory, field, and underground investigations. It should be emphasized that the DOE has not made any decisions regarding the disposition of DOE HLW and DOE SNF. Furthermore, the safety case discussed herein is not intended to either site a repository in the Delaware Basin or preclude siting in other media at other locations. Rather, this study simply presents an approach for accelerated development of a safety case for a potential DOE HLW and DOE SNF repository using the currently available technical basis for bedded salt. This approach includes a summary of the regulatory environment relevant to disposal of DOE HLW and DOE SNF in a deep geologic repository, the key elements of a safety case, the evolution of the safety case through the successive phases of repository development and licensing, and the existing technical basis that could be used to substantiate the safety of a geologic repository if it were to be sited in the Delaware Basin. We also discuss the potential role of an underground research laboratory (URL). (authors)« less

Analysis of ancient-river systems by 3D seismic time-slice technique: A case study in northeast Malay Basin, offshore Terengganu, Malaysia

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sulaiman, Noorzamzarina; Hamzah, Umar; Samsudin, Abdul Rahim

2014-09-03

Fluvial sandstones constitute one of the major clastic petroleum reservoir types in many sedimentary basins around the world. This study is based on the analysis of high-resolution, shallow (seabed to 500 m depth) 3D seismic data which generated three-dimensional (3D) time slices that provide exceptional imaging of the geometry, dimension and temporal and spatial distribution of fluvial channels. The study area is in the northeast of Malay Basin about 280 km to the east of Terengganu offshore. The Malay Basin comprises a thick (> 8 km), rift to post-rift Oligo-Miocene to Pliocene basin-fill. The youngest (Miocene to Pliocene), post-rift successionmore » is dominated by a thick (1–5 km), cyclic succession of coastal plain and coastal deposits, which accumulated in a humid-tropical climatic setting. This study focuses on the Pleistocene to Recent (500 m thick) succession, which comprises a range of seismic facies analysis of the two-dimensional (2D) seismic sections, mainly reflecting changes in fluvial channel style and river architecture. The succession has been divided into four seismic units (Unit S1-S4), bounded by basin-wide strata surfaces. Two types of boundaries have been identified: 1) a boundary that is defined by a regionally-extensive erosion surface at the base of a prominent incised valley (S3 and S4); 2) a sequence boundary that is defined by more weakly-incised, straight and low-sinuosity channels which is interpreted as low-stand alluvial bypass channel systems (S1 and S2). Each unit displays a predictable vertical change of the channel pattern and scale, with wide low-sinuosity channels at the base passing gradationally upwards into narrow high-sinuosity channels at the top. The wide variation in channel style and size is interpreted to be controlled mainly by the sea-level fluctuations on the widely flat Sunda land Platform.« less

Analysis of ancient-river systems by 3D seismic time-slice technique: A case study in northeast Malay Basin, offshore Terengganu, Malaysia

NASA Astrophysics Data System (ADS)

Sulaiman, Noorzamzarina; Hamzah, Umar; Samsudin, Abdul Rahim

2014-09-01

Fluvial sandstones constitute one of the major clastic petroleum reservoir types in many sedimentary basins around the world. This study is based on the analysis of high-resolution, shallow (seabed to 500 m depth) 3D seismic data which generated three-dimensional (3D) time slices that provide exceptional imaging of the geometry, dimension and temporal and spatial distribution of fluvial channels. The study area is in the northeast of Malay Basin about 280 km to the east of Terengganu offshore. The Malay Basin comprises a thick (> 8 km), rift to post-rift Oligo-Miocene to Pliocene basin-fill. The youngest (Miocene to Pliocene), post-rift succession is dominated by a thick (1-5 km), cyclic succession of coastal plain and coastal deposits, which accumulated in a humid-tropical climatic setting. This study focuses on the Pleistocene to Recent (500 m thick) succession, which comprises a range of seismic facies analysis of the two-dimensional (2D) seismic sections, mainly reflecting changes in fluvial channel style and river architecture. The succession has been divided into four seismic units (Unit S1-S4), bounded by basin-wide strata surfaces. Two types of boundaries have been identified: 1) a boundary that is defined by a regionally-extensive erosion surface at the base of a prominent incised valley (S3 and S4); 2) a sequence boundary that is defined by more weakly-incised, straight and low-sinuosity channels which is interpreted as low-stand alluvial bypass channel systems (S1 and S2). Each unit displays a predictable vertical change of the channel pattern and scale, with wide low-sinuosity channels at the base passing gradationally upwards into narrow high-sinuosity channels at the top. The wide variation in channel style and size is interpreted to be controlled mainly by the sea-level fluctuations on the widely flat Sunda land Platform.

River water quality assessment using environmentric techniques: case study of Jakara River Basin.

PubMed

Mustapha, Adamu; Aris, Ahmad Zaharin; Juahir, Hafizan; Ramli, Mohammad Firuz; Kura, Nura Umar

2013-08-01

Jakara River Basin has been extensively studied to assess the overall water quality and to identify the major variables responsible for water quality variations in the basin. A total of 27 sampling points were selected in the riverine network of the Upper Jakara River Basin. Water samples were collected in triplicate and analyzed for physicochemical variables. Pearson product-moment correlation analysis was conducted to evaluate the relationship of water quality parameters and revealed a significant relationship between salinity, conductivity with dissolved solids (DS) and 5-day biochemical oxygen demand (BOD5), chemical oxygen demand (COD), and nitrogen in form of ammonia (NH4). Partial correlation analysis (r p) results showed that there is a strong relationship between salinity and turbidity (r p=0.930, p=0.001) and BOD5 and COD (r p=0.839, p=0.001) controlling for the linear effects of conductivity and NH4, respectively. Principal component analysis and or factor analysis was used to investigate the origin of each water quality parameter in the Jakara Basin and identified three major factors explaining 68.11 % of the total variance in water quality. The major variations are related to anthropogenic activities (irrigation agricultural, construction activities, clearing of land, and domestic waste disposal) and natural processes (erosion of river bank and runoff). Discriminant analysis (DA) was applied on the dataset to maximize the similarities between group relative to within-group variance of the parameters. DA provided better results with great discriminatory ability using eight variables (DO, BOD5, COD, SS, NH4, conductivity, salinity, and DS) as the most statistically significantly responsible for surface water quality variation in the area. The present study, however, makes several noteworthy contributions to the existing knowledge on the spatial variations of surface water quality and is believed to serve as a baseline data for further studies. Future research should therefore concentrate on the investigation of temporal variations of water quality in the basin.

Study on the contribution of cryosphere to runoff in the cold alpine basin: A case study of Hulugou River Basin in the Qilian Mountains

NASA Astrophysics Data System (ADS)

Zongxing, Li; Qi, Feng; Wei, Liu; Tingting, Wang; Aifang, Cheng; Yan, Gao; Xiaoyan, Guo; Yanhui, Pan; Jianguo, Li; Rui, Guo; Bing, Jia

2014-11-01

Global warming would inevitably lead to the increased glacier-snow meltwater and mountainous discharge. Taking an example the Hulugou River Basin in the Qilian Mountains, this study confirmed the contribution of cryosphere to runoff by means of the isotope hydrograph separation. The hydro-geochemistry and the isotope geochemistry suggested that both the meltwater and rainwater infiltrated into the subsurface and fed into the river runoff of the Hulugou River Basin in the form of springs. The isotopic composition of river water and underground water was close to the Local Meteoric Water Line, and the δ18O and δD ranged among precipitation, glacier-snow meltwater and frozen soil meltwater. The results indicated that 68% of the recharge of the Hulugou River water was the precipitation, thereinto, glacier-snow meltwater and frozen soil meltwater contributing 11% and 21%, respectively. For tributary-1, precipitation accounted for 77% of the total stream runoff, with frozen soil meltwater accounting for 17%, and glacier-snow meltwater only supplied 6%. During the sampling period, the contribution of surface runoff from precipitation was 44% to tributary-2, and glacier-snow meltwater had contributed 42%; only 14% from frozen soil meltwater. For tributary-3, precipitation accounted for 63% of the total runoff, and other 37% originated from the frozen soil meltwater. According to the latest observational data, the glacier-snow meltwater has accounted for 11.36% of the total runoff in the stream outlet, in which the calculation has been verified by hydrograph separation. It is obvious that the contribution of cryosphere has accounted for 1/3 of the outlet runoff in the Hulugou River Basin, which has been an important part of river sources. This study demonstrated that the alpine regions of western China, especially those basins with glaciers, snow and frozen soil, have played a crucial role in regional water resource provision under global warming.

Ancient Mitochondrial Capture as Factor Promoting Mitonuclear Discordance in Freshwater Fishes: A Case Study in the Genus Squalius (Actinopterygii, Cyprinidae) in Greece

PubMed Central

Vukić, Jasna; Šanda, Radek; Doadrio, Ignacio

2016-01-01

Hybridization and incomplete lineage sorting are common confounding factors in phylogeny and speciation resulting in mitonuclear disparity. Mitochondrial introgression, a particular case of hybridization, may, in extreme cases, lead to replacement of the mitochondrial genome of one species with that of another (mitochondrial capture). We investigated mitochondrial introgression involving two species of the cyprinid genus Squalius in the western Peloponnese region of Greece using molecular and morphological data. We found evidence of complete mitochondrial introgression of Squalius keadicus into two populations recognized as Squalius peloponensis from the Miras and Pamissos River basins and a divergence of mitochondrial genomes of S. keadicus from the Evrotas basin from that of the introgressed populations dating from the Pleistocene. Secondary contact among basins is a possible factor in connection of the species and the introgression event. Morphological analyses support the hypothesis of mitochondrial introgression, as S. keadicus was different from the other three populations recognized as S. peloponensis, although significant differences were found among the four populations. Isolation by geographical barriers arose during Pleistocene in the western Peloponnese were the source of the evolution of the two reciprocally monophyletic subclades found in the S. keadicus mitochondrial clade, and the morphological differences found among the four populations. Along with the lack of structure in the nuclear genome in the three populations ascribed to S. peloponensis, this suggests an incipient speciation process occurring in these Squalius species in the western Peloponnese. PMID:27906993

Evaluating Biodiversity Response toForecasted Land Use Change: A Case Study in the South Platte River Basin, Colorado

EPA Science Inventory

Effects of future land use change on watersheds have important management implications. Seamless, national-scale land-use-change scenarios for developed land were acquired from the U.S. Environmental Protection Agency Integrated Climate and Land Use Scenarios (lCLUS) project and...

Developing Better Environmental Assessment and Protection Strategies: A Case Example on Early Detection Monitoring for Aquatic Invasive Species

EPA Science Inventory

A principal theme of our research group is to develop, evaluate, and improve monitoring approaches, ecological assessments, and environmental protection strategies. Over the past decade, we have conducted a number of studies under this general theme, across the Great Lakes basin...

Variations in annual water-energy balance and their correlations with vegetation and soil moisture dynamics: A case study in the Wei River Basin, China

DOE Office of Scientific and Technical Information (OSTI.GOV)

Huang, Shengzhi; Huang, Qiang; Leng, Guoyong

It is of importance to investigate watershed water-energy balance variations and to explore their correlations with vegetation and soil moisture dynamics, which helps better understand the interplays between underlying surface dynamics and the terrestrial water cycle. The heuristic segmentation method was adopted to identify change points in the parameter to series in Fu's equation belonging to the Budyko framework in the Wei River Basin (WRB) and its sub-basins aiming to examine the validity of stationary assumptions. Additionally, the cross wavelet analysis was applied to explore the correlations between vegetation and soil moisture dynamics and to variations. Results indicated that (1)more » the omega variations in the WRB are significant, with some change points identified except for the sub-basin above Zhangjiashan, implying that the stationarity of omega series in the WRB is invalid except for the sub-basin above Zhangjiashan; (2) the correlations between soil moisture series and to series are weaker than those between Normalized Difference Vegetation Index (NDVI) series and omega series; (3) vegetation dynamics show significantly negative correlations with omega variations in 1983-2003 with a 4-8 year signal in the whole WRB, and both vegetation and soil moisture dynamics exert strong impacts on the parameter omega changes. This study helps understanding the interactions between underlying land surface dynamics and watershed water-energy balance. (C) 2017 Elsevier B.V. All rights reserved.« less

Producing Information for Corine Database by Using Classification Method: a Case Study of Sazlidere Basin, Istanbul

NASA Astrophysics Data System (ADS)

Sarıyılmaz, F. B.; Musaoğlu, N.; Uluğtekin, N.

2017-11-01

The Sazlidere Basin is located on the European side of Istanbul within the borders of Arnavutkoy and Basaksehir districts. The total area of the basin, which is largely located within the province of Arnavutkoy, is approximately 177 km2. The Sazlidere Basin is faced with intense urbanization pressures and land use / cover change due to the Northern Marmara Motorway, 3rd airport and Channel Istanbul Projects, which are planned to be realized in the Arnavutkoy region. Due to the mentioned projects, intense land use /cover changes occur in the basin. In this study, 2000 and 2012 dated LANDSAT images were supervised classified based on CORINE Land Cover first level to determine the land use/cover classes. As a result, four information classes were identified. These classes are water bodies, forest and semi-natural areas, agricultural areas and artificial surfaces. Accuracy analysis of the images were performed following the classification process. The supervised classified images that have the smallest mapping units 0.09 ha and 0.64 ha were generalized to be compatible with the CORINE Land Cover data. The image pixels have been rearranged by using the thematic pixel aggregation method as the smallest mapping unit is 25 ha. These results were compared with CORINE Land Cover 2000 and CORINE Land Cover 2012, which were obtained by digitizing land cover and land use classes on satellite images. It has been determined that the compared results are compatible with each other in terms of quality and quantity.

Do interactions of land use and climate affect productivity of waterbirds and prairie-pothole wetlands?

USGS Publications Warehouse

Anteau, Michael J.

2012-01-01

Availability of aquatic invertebrates on migration and breeding areas influences recruitment of ducks and shorebirds. In wetlands of Prairie Pothole Region (PPR), aquatic invertebrate production primarily is driven by interannual fluctuations of water levels in response to wet-dry cycles in climate. However, this understanding comes from studying basins that are minimally impacted by agricultural landscape modifications. In the past 100–150 years, a large proportion of wetlands within the PPR have been altered; often water was drained from smaller to larger wetlands at lower elevations creating consolidated, interconnected basins. Here I present a case study and I hypothesize that large basins receiving inflow from consolidation drainage have reduced water-level fluctuations in response to climate cycles than those in undrained landscapes, resulting in relatively stable wetlands that have lower densities of invertebrate forage for ducks and shorebirds and also less foraging habitat, especially for shorebirds. Furthermore, stable water-levels and interconnected basins may favor introduced or invasive species (e.g., cattail [Typha spp.] or fish) because native communities "evolved" in a dynamic and isolated system. Accordingly, understanding interactions between water-level fluctuations and landscape modifications is a prerequisite step to modeling effects of climate change on wetland hydrology and productivity and concomitant recruitment of waterbirds.

Farmers' attitudes toward mandatory water-saving policies: A case study in two basins in northwest China.

PubMed

Chang, Genying; Wang, Lu; Meng, Liuyi; Zhang, Wenxia

2016-10-01

China began to implement stringent water-saving policies in 2012. Mandatory water-saving measures implemented in arid inland river basins include the measures of allocating surface water among upper, middle and lower beaches, restricting household agricultural water use, closing wells, reducing farmland and increasing water prices. These measures have negative influences on the agricultural production of farmers. This study aimed to reveal the demographic and psychological correlates of farmers' attitudes toward these policies. The participants included 672 farmers in the Heihe River Basin and the Shule River Basin in northwest China. Structural equation analyses showed that farmers' awareness of the beneficial consequences of restricting household agricultural water and their perception of policy enforcement had significant relationships with their attitudes toward water-saving policies, whereas the effects of the New Ecological Paradigm and collectivism on farmers' attitudes were mediated through their awareness of beneficial consequences and their perception of policy enforcement. Multivariable regression analyses revealed that as a whole, there were no significant correlations between demographic variables and farmers' attitudes. Policy implications include propagandizing these policies among local farmers, strengthening open and fair policy enforcement, and cautiously using water prices as an instrument to control irrigation water. Copyright © 2016 Elsevier Ltd. All rights reserved.

Using GRACE to constrain precipitation amount over cold mountainous basins

NASA Astrophysics Data System (ADS)

Behrangi, Ali; Gardner, Alex S.; Reager, John T.; Fisher, Joshua B.

2017-01-01

Despite the importance for hydrology and climate-change studies, current quantitative knowledge on the amount and distribution of precipitation in mountainous and high-elevation regions is limited due to instrumental and retrieval shortcomings. Here by focusing on two large endorheic basins in High Mountain Asia, we show that satellite gravimetry (Gravity Recovery and Climate Experiment (GRACE)) can be used to provide an independent estimate of monthly accumulated precipitation using mass balance equation. Results showed that the GRACE-based precipitation estimate has the highest agreement with most of the commonly used precipitation products in summer, but it deviates from them in cold months, when the other products are expected to have larger errors. It was found that most of the products capture about or less than 50% of the total precipitation estimated using GRACE in winter. Overall, Global Precipitation Climatology Project (GPCP) showed better agreement with GRACE estimate than other products. Yet on average GRACE showed 30% more annual precipitation than GPCP in the study basins. In basins of appropriate size with an absence of dense ground measurements, as is a typical case in cold mountainous regions, we find GRACE can be a viable alternative to constrain monthly and seasonal precipitation estimates from other remotely sensed precipitation products that show large bias.

Identification of Critical Erosion Prone Areas and Computation of Sediment Yield Using Remote Sensing and GIS: A Case Study on Sarada River Basin

NASA Astrophysics Data System (ADS)

Sundara Kumar, P.; Venkata Praveen, T.; Anjanaya Prasad, M.; Santha Rao, P.

2018-06-01

The two most important resources blessed by nature to the mankind are land and water. Undoubtedly, these gifts have to be conserved and maintained with unflinching efforts from every one of us for an effective environmental and ecological balance. The efforts and energy of water resources engineers and conservationists are going in this direction to conserve these precious resources of nature. The present study is an attempt to develop suitable methodology to facilitate decision makers to conserve the resources and also reflects the cause mentioned above has been presented here. The main focus of this study is to identify the critical prone areas for soil erosion and computation of sediment yield in a small basin using Universal Soil Loss Equation and Modified Universal Soil Loss Equation (MUSLE) respectively. The developed model has been applied on Sarada river basin which has a drainage area of 1252.99 km2. This river is located in Andhra Pradesh State (AP), India. The basin has been divided into micro basins for effective estimation and also for precise identification of the areas that are prone to soil erosion. Remote Sensing and Geographic Information Systems tools were used to generate and spatially organize the data that is required for soil erosion modeling. It was found that the micro basins with very severe soil erosion are consisting of hilly areas with high topographic factor and 38.01% of the study area has the rate erosion more than 20 t/ha/year and hence requires an immediate attention from the soil conservation point of view. In this study region, though there is one discharge measuring gauge station available at Anakapalli but there is no sediment yield gauging means available to compute the sediment yield. Therefore, to arrive at the suspended-sediment concentration was a challenge task. In the present study the sediment measurement has been carried out with an instrument (DH-48), sediment sampling equipment as per IS: 4890-1968, has been used. Suspended-sediment samples were collected and sediment yield was arrived at the site by using this instrument. The sediment yield was also computed using MUSLE. Data for this model study has been generated from the samples collected from 28 storm events spread over a time span of 1 year, at the outlet of the basin at Anakapalli for computation of sediment yield. The sediment yield as estimated by MUSLE model has been successfully compared with the sediment yield measured at the outlet of the basin by sediment yield measuring unit and found fairly good correlation between them. Hence the developed methodology will be useful to estimate the sediment yield in the hydrologically similar basins that are not gauged for sediment yield.

Fate and Transport of Cohesive Sediment and HCB in the Middle Elbe River Basin

NASA Astrophysics Data System (ADS)

Moshenberg, Kari; Heise, Susanne; Calmano, Wolfgang

2014-05-01

Chemical contamination of waterways and floodplains is a pervasive environmental problem that threatens aquatic ecosystems worldwide. Due to extensive historical contamination and redistribution of contaminated sediments throughout the basin, the Elbe River transports significant loads of contaminants downstream, particularly during flood events. This study focuses on Hexachlorobenzene (HCB), a persistent organic pollutant that has been identified as a contaminant of concern in the Elbe Basin. To better understand the fate and transport of cohesive sediments and sediment-sorbed HCB, a hydrodynamic, suspended sediment, and contaminated transport model for the 271-km reach of the Elbe River basin between Dresden and Magdeburg was developed. Additionally, trends in suspended sediment and contaminant transport were investigated in the context of the recent high frequency of floods in the Elbe Basin. This study presents strong evidence that extreme high water events, such as the August, 2002 floods, have a permanent effect on the sediment transport regime in the Elbe River. Additionally, results indicate that a significant component annual HCB loads are transported downstream during floods. Additionally, modeled results for suspended sediment and HCB accumulation on floodplains are presented and discussed. Uncertainty and issues related to model development are also addressed. A worst case analysis of HCB uptake by dairy cows and beef cattle indicate that significant, biologically relevant quantities of sediment-sorbed HCB accumulate on the Elbe floodplains following flood events. Given both the recent high frequency of floods in the Elbe Basin, and the potential increase in flood frequency due to climate change, an evaluation of source control measures and/or additional monitoring of floodplain soils and grasses is recommended.

Comparative study of transport processes of nitrogen, phosphorus, and herbicides to streams in five agricultural basins, USA

USGS Publications Warehouse

Domagalski, Joseph L.; Ator, S.; Coupe, R.; McCarthy, K.; Lampe, D.; Sandstrom, M.; Baker, N.

2008-01-01

Agricultural chemical transport to surface water and the linkage to other hydrological compartments, principally ground water, was investigated at five watersheds in semiarid to humid climatic settings. Chemical transport was affected by storm water runoff, soil drainage, irrigation, and how streams were linked to shallow ground water systems. Irrigation practices and timing of chemical use greatly affected nutrient and pesticide transport in the semiarid basins. Irrigation with imported water tended to increase ground water and chemical transport, whereas the use of locally pumped irrigation water may eliminate connections between streams and ground water, resulting in lower annual loads. Drainage pathways in humid environments are important because the loads may be transported in tile drains, or through varying combinations of ground water discharge, and overland flow. In most cases, overland flow contributed the greatest loads, but a significant portion of the annual load of nitrate and some pesticide degradates can be transported under base-flow conditions. The highest basin yields for nitrate were measured in a semiarid irrigated system that used imported water and in a stream dominated by tile drainage in a humid environment. Pesticide loads, as a percent of actual use (LAPU), showed the effects of climate and geohydrologic conditions. The LAPU values in the semiarid study basin in Washington were generally low because most of the load was transported in ground water discharge to the stream. When herbicides are applied during the rainy season in a semiarid setting, such as simazine in the California basin, LAPU values are similar to those in the Midwest basins. Copyright ?? 2008 by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America. All rights reserved.

A Method to Estimate Sunshine Duration Using Cloud Classification Data from a Geostationary Meteorological Satellite (FY-2D) over the Heihe River Basin.

PubMed

Wu, Bingfang; Liu, Shufu; Zhu, Weiwei; Yu, Mingzhao; Yan, Nana; Xing, Qiang

2016-11-04

Sunshine duration is an important variable that is widely used in atmospheric energy balance studies, analysis of the thermal loadings on buildings, climate research, and the evaluation of agricultural resources. In most cases, it is calculated using an interpolation method based on regional-scale meteorological data from field stations. Accurate values in the field are difficult to obtain without ground measurements. In this paper, a satellite-based method to estimate sunshine duration is introduced and applied over the Heihe River Basin. This method is based on hourly cloud classification product data from the FY-2D geostationary meteorological satellite (FY-2D). A new index-FY-2D cloud type sunshine factor-is proposed, and the Shuffled Complex Evolution Algorithm (SCE-UA) was used to calibrate sunshine factors from different coverage types based on ground measurement data from the Heihe River Basin in 2007. The estimated sunshine duration from the proposed new algorithm was validated with ground observation data for 12 months in 2008, and the spatial distribution was compared with the results of an interpolation method over the Heihe River Basin. The study demonstrates that geostationary satellite data can be used to successfully estimate sunshine duration. Potential applications include climate research, energy balance studies, and global estimations of evapotranspiration.

A Method to Estimate Sunshine Duration Using Cloud Classification Data from a Geostationary Meteorological Satellite (FY-2D) over the Heihe River Basin

PubMed Central

Wu, Bingfang; Liu, Shufu; Zhu, Weiwei; Yu, Mingzhao; Yan, Nana; Xing, Qiang

2016-01-01

Sunshine duration is an important variable that is widely used in atmospheric energy balance studies, analysis of the thermal loadings on buildings, climate research, and the evaluation of agricultural resources. In most cases, it is calculated using an interpolation method based on regional-scale meteorological data from field stations. Accurate values in the field are difficult to obtain without ground measurements. In this paper, a satellite-based method to estimate sunshine duration is introduced and applied over the Heihe River Basin. This method is based on hourly cloud classification product data from the FY-2D geostationary meteorological satellite (FY-2D). A new index—FY-2D cloud type sunshine factor—is proposed, and the Shuffled Complex Evolution Algorithm (SCE-UA) was used to calibrate sunshine factors from different coverage types based on ground measurement data from the Heihe River Basin in 2007. The estimated sunshine duration from the proposed new algorithm was validated with ground observation data for 12 months in 2008, and the spatial distribution was compared with the results of an interpolation method over the Heihe River Basin. The study demonstrates that geostationary satellite data can be used to successfully estimate sunshine duration. Potential applications include climate research, energy balance studies, and global estimations of evapotranspiration. PMID:27827935

Modeling of Soil Erosion by IntErO model: The Case Study of the Novsicki Potok Watershed, of the Prokletije high mountains of Montenegro

NASA Astrophysics Data System (ADS)

Spalevic, Velibor; Al-Turki, Ali M.; Barovic, Goran; Leandro Naves Silva, Marx; Djurovic, Nevenka; Soares Souza, Walisson; Veloso Gomes Batista, Pedro; Curovic, Milic

2016-04-01

The application of soil conservation programs to combat erosion and sedimentation are significantly contributing to the protection of the natural resources. Watershed management practices include the assessment of Physical-Geographical, Climate, Geological, Pedological characteristics, including the analysis of Land Use of the regions concerned. The policy makers are increasingly looking for the different land uses and climatic scenarios that can be used for valuable projections for watershed management. To increase knowledge about those processes, use of hydrological and soil erosion models is needed and that is allowing quantification of soil redistribution and sediment productions. We focused on soil erosion processes in one of Northern Montenegrin mountain watersheds, the Novsicki Potok Watershed of the Polimlje River Basin, using modeling techniques: the IntErO model for calculation of runoff and soil loss. The model outcomes were validated through measurements of lake sediment deposition at the Potpec hydropower plant dam. Our findings indicate a medium potential of soil erosion risk. With 464 m³ yr-1 of annual sediment yield, corresponding to an area-specific sediment yield of 270 m³km-2 yr-1, the Novsicki Potok drainage basin belongs to the Montenegrin basins with the medium sediment discharge; according to the erosion type, it is surface erosion. The value of the Z coefficient was calculated on 0.403, what indicates that the river basin belongs to 3rd destruction category (of five). Our results suggest that the calculated peak discharge from the river basin was 82 m3s-1 for the incidence of 100 years. According to our analysis there is a possibility for large flood waves to appear in the studied river basin. With this research we, to some extent, improved the knowledge on the status of sediment yield and runoff of the river basins of Montenegro, where the map of Soil erosion is still not prepared. The IntErO model we used in this study is relatively novel concept and is highly recommended for soil erosion modelling in other river basins similar to the studied watershed, because of its simple identification of critical areas affected by the soil loss caused by soil erosion.

Integrated flood damage modelling in the Ebro river basin under hydrodynamic, socio-economic and environmental factors

NASA Astrophysics Data System (ADS)

Foudi, S.; Galarraga, I.; Osés, N.

2012-04-01

This paper presents a model of flood damage measurement. It studies the socio-economic and environmental potential damage of floods in the Ebro river basin. We estimate the damage to the urban, rural and environmental sectors. In these sectors, we make distinctions between residential, non residential, cultural, agricultural, public facilities and utilities, environmental and human subsectors. We focus on both the direct, indirect, tangible and intangible impacts. The residential damages refer to the damages on housing, costs of repair and cleaning as direct effects and the re-housing costs as an indirect effect. The non residential and agricultural impacts concern the losses to the economic sectors (industry, business, agricultural): production, capital losses, costs of cleaning and repairs for the direct costs and the consequences of the suspension of activities for the indirect costs. For the human sector, we refer to the physical impacts (injuries and death) in the direct tangible effects and to the posttraumatic stress as indirect intangible impact. The environmental impacts focus on a site of Community Interests (pSCIs) in the case study area. The case study is located the Ebro river basin, Spain. The Ebro river basin is the larger river basin in term of surface and water discharge. The Ebro river system is subject to Atlantic and Mediterranean climatic influences. It gathers most of its water from the north of Spain (in the Pyrenees Mountains) and is the most important river basin of Spain in term of water resources. Most of the flooding occurs during the winter period. Between 1900- 2010, the National Catalogue of Historical Floods identifies 372 events: meanly 33 events every 10 years and up to 58 during the 1990-2000. Natural floods have two origins: (i) persistent rainfalls in large sub basins raised up by high temperature giving rise to a rapid thaw in the Pyrenees, (ii) local rainfalls of short duration and high intensity that gives rise to rapid and wrenching floods. Our integrated model combines hydrologic, land use, environmental and economic data. The combination of the cadastral data with the flood characteristics (flow, depth, duration) for various periods of return enables to draw damage maps expressed as function of flood characteristics (Penning-Rowsell et al. 2005). This methodology also enables to illustrate consequences of risk prevention measures. We can thus measure the value of information in the alert system of Civil Protection Agency, give information on risks for urban development plans and simulate the consequences of hydraulic interventions like river bed cleaning. This methodology would then contribute to match with the requirements of the 2007 EU flood risk Management Directive (2007/60/CE).

Water - Essential Resource of the Southern Flint River Basin, Georgia

USGS Publications Warehouse

Warner, Debbie; Norton, Virgil

2004-01-01

Introduction Abundant water resources of the Flint River Basin have played a major role in the history and development of southwestern Georgia. The Flint River-along with its tributaries, wetlands, and swamps-and the productive aquifers of the river basin are essential components of the area's diverse ecosystems. These resources also are necessary for sustained agricultural, industrial, and municipal activities. Increasing, and in some cases conflicting, demand for water makes careful monitoring and wise planning and management of southwestern Georgia's water resources critical to the ecological and economic future of the area. This poster presents the major issues associated with increasing competition for water resources in the southern Flint River Basin.

Transition from marine deep slope deposits to evaporitic facies of an isolated foreland basin: case study of the Sivas Basin (Turkey)

NASA Astrophysics Data System (ADS)

Pichat, Alexandre; Hoareau, Guilhem; Legeay, Etienne; Lopez, Michel; Bonnel, Cédric; Callot, Jean-Paul; Ringenbach, Jean-Claude

2017-04-01

The Sivas Basin, located in the central part of the Anatolian Plateau in Turkey, formed after the closure of the northern Neotethys from Paleocene to Pliocene times. It developed over an ophiolitic basement obducted from the north during the Late Cretaceous. During Paleocene to Eocene times, the onset of the Tauride compression led to the development of a foreland basin affected by north-directed thrusts. The associate general deepening of the basin favored the accumulation of a thick marine turbiditic succession in the foredeep area, followed by a fast shallowing of the basin and thick evaporitic sequence deposition during the late Eocene. We present here the detailed sedimentological architecture of this flysch to evaporite transition. In the northern part of the basin, volcanoclastic turbidites gradually evolved into basinal to prodelta deposits regularly fed by siliciclastic material during flood events. Locally (to the NE), thick-channelized sandstones are attributed to the progradation of delta front distributary channels. The basin became increasingly sediment-starved and evolved toward azoic carbonates and shaly facies, interlayered with organic-rich shales before the first evaporitic deposits. In the southern part of the basin, in the central foredeep, the basinal turbidites become increasingly gypsum-rich and record a massive mega-slump enclosing olistoliths of gypsum and of ophiolitic rocks. Such reworked evaporites were fed by the gravitational collapsing of shallow water evaporites that had previously precipitated in silled piggy-back basins along the southern fold-and-thrust-belt of the Sivas Basin. Tectonic activity that led to the dismantlement of such evaporites probably also contributed to the closure of the basin from the marine domain. From the north to the south, subsequent deposits consist in about 70 meters of secondary massive to fine-grained gypsiferous beds interpreted as recording high to low density gypsum turbidites. Such facies were probably fed from shallow water evaporitic platforms developing contemporaneously along the borders of the halite-? and gypsum-saturated basin. Finally, the reworked evaporites are sealed by a thick (> 100 m) chaotic and coarse crystalline gypsum mass, carrying folded rafts and boudins of carbonate and gypsum beds. Such unit is interpreted as a gypsiferous caprock resulting from the leaching of significant amount of halite deposits. Gypsum crystals are secondary and grew from the hydration of anhydrite grains left as a residual phase after the leaching of halite. The halite probably formed in a perennial shallow hypersaline basin fed in solute by marine seepages. This former halite sequence is interpreted to have triggered mini-basin salt tectonics during the Oligo-Miocene. The described facies and proposed scenario of the Tuzhisar Formation in the central part of the Sivas Basin may find analogies with other Central Anatolian Basins (e.g. the Ulukisla Basin) or with other basin-wide salt accumulations in the world (e.g. in the Carpathian Foredeep).

Analysis of reworked sediments as a basis of the Palaeogene-Neogene palaeogeography reinterpretation: Case study of the Roztocze region (SE Poland)

NASA Astrophysics Data System (ADS)

Margielewski, Włodzimierz; Jankowski, Leszek; Krąpiec, Marek; Garecka, Małgorzata; Hałas, Stanisław; Urban, Jan

2017-05-01

Radiometric K/Ar dating of glauconite and nanno- and micropaleontologic analyses of calcareous nannoplankton, foraminifers and dinoflagellates isolated from the Miocene rocks in the Polish part of the Roztocze region, a northeastern part of the fore-bulge of the Carpathian Foreland Basin System - CFBS), SE Poland, reveal that these strata contain numerous microfossils and glauconite grains of the Upper Eocene and Lower Oligocene age. Such occurrences clearly indicate that these materials were redeposited from the Upper Eocene and Lower Oligocene marine rocks that must have originally covered most of the Roztocze and the surrounding area. It is therefore proposed herein that the geographical extent of the boreal, epi-continental basin during the Eocene-Oligocene was much greater than previously considered. Moreover, it appears that this basin was connected with the back-bulge zone of the warm Carpathian Basin (originally a northern part of the Tethys Basin which since Eocene/Oligocene boundary remained isolated as the Paratethys Basin). Hence, it is unlikely that the Roztocze region was uplifted during the Palaeogene as part of the Meta-Carpathian Swell, as it was earlied hypothesized. Instead, the Roztocze Swell formed during the Sarmatian, in the last stage of the development of the fore-bulge structure in the foreland of the up-thrust Carpathian orogenic belt. Multiple redeposition of sediments is the reason that the absolute dating (K/Ar) of glauconite, as well as incomprehensive palaeontological analysis could result in erroneous stratigraphic and palaeogeographic interpretations.

Holistic uncertainty analysis in river basin modeling for climate vulnerability assessment

NASA Astrophysics Data System (ADS)

Taner, M. U.; Wi, S.; Brown, C.

2017-12-01

The challenges posed by uncertain future climate are a prominent concern for water resources managers. A number of frameworks exist for assessing the impacts of climate-related uncertainty, including internal climate variability and anthropogenic climate change, such as scenario-based approaches and vulnerability-based approaches. While in many cases climate uncertainty may be dominant, other factors such as future evolution of the river basin, hydrologic response and reservoir operations are potentially significant sources of uncertainty. While uncertainty associated with modeling hydrologic response has received attention, very little attention has focused on the range of uncertainty and possible effects of the water resources infrastructure and management. This work presents a holistic framework that allows analysis of climate, hydrologic and water management uncertainty in water resources systems analysis with the aid of a water system model designed to integrate component models for hydrology processes and water management activities. The uncertainties explored include those associated with climate variability and change, hydrologic model parameters, and water system operation rules. A Bayesian framework is used to quantify and model the uncertainties at each modeling steps in integrated fashion, including prior and the likelihood information about model parameters. The framework is demonstrated in a case study for the St. Croix Basin located at border of United States and Canada.

Effectiveness of residential wood-burning regulation on decreasing particulate matter levels and hospitalizations in the San Joaquin Valley Air Basin.

PubMed

Yap, Poh-Sin; Garcia, Cynthia

2015-04-01

We examined the impact of Rule 4901, aimed at reducing residential wood burning, on particulate matter levels and hospitalizations in the San Joaquin Valley Air Basin (SJVAB). Using general linear mixed models and generalized estimating equation models, we compared levels of particulate matter and of hospital admissions (age groups = 45-64 and ≥ 65 years) in the SJVAB for cardiovascular disease (CVD), ischemic heart disease (IHD), and chronic obstructive pulmonary disease during the burn seasons before (2000-2003) and after (2003-2006) implementation. After implementation, we observed reductions of 12%, 11%, and 15% in particulate matter  2.5 micrometers in diameter or smaller (PM2.5), and 8%, 7%, and 11% in coarse particles, in the entire SJVAB and in rural and urban regions of the air basin, respectively. Among those aged 65 years and older, Rule 4901 was estimated to prevent 7%, 8%, and 5% of CVD cases, and 16%, 17%, and 13% of IHD cases, in the entire SJVAB and in rural and urban regions, respectively. The study suggests that Rule 4901 is effective at reducing wintertime ambient PM2.5 levels and decreasing hospital admissions for heart disease among people aged 65 years and older.

The Quequén Salado river basin: Geology and biochronostratigraphy of the Mio-Pliocene boundary in the southern Pampean plain, Argentina

NASA Astrophysics Data System (ADS)

Beilinson, E.; Gasparini, G. M.; Tomassini, R. L.; Zárate, M. A.; Deschamps, C. M.; Barendregt, R. W.; Rabassa, J.

2017-07-01

The Quequén Salado river basin has been the focus of several contributions since the first decades of the XX century, namely dealing with the general geological features of the deposits and with the vertebrate remains. In this paper, the Neogene geological history documented by the Quequén Salado river exposures is reconstructed by means of stratigraphic, sedimentological and paleomagnetic studies along with the paleontological analysis of vertebrate remains. The study area is a crucial setting not only to better understand the evolution of the southern Pampas basin during the late Miocene-early Pliocene interval, but also to test the validity of the biochronologic and biostratigraphic schemes, especially the "Irenense". A geological model for the Quequén Salado river valley is proposed: a case of downcutting and headward erosion that contributes with a coherent interpretation to explain the spatial distribution of facies and fossil taxa: the younger in the distal sector of the Quequén Salado middle basin and the older in the lower basin. The sedimentary record is believed to represent the distal reaches of a distributary fluvial system that drained from the Ventania ranges. The stratigraphic section of Paso del Indio Rico results a key stratigraphic site to fully understand the stratigraphic nature of the boundary between the Miocene and the Pliocene (the Huayquerian and Montehermosan stages/ages). In this sense, two stratigraphically superposed range zones have been recognized in the area: Xenodontomys ellipticus Range Zone (latest Miocene-early Pliocene; late Huayquerian), and Eumysops laeviplicatus Range Zone (early Pliocene; Montehermosan). Taking into account the available geological and paleontological evidences, the "Irenense" would not represent a valid biostratigraphic unit, since, according to the geological model here proposed, it would be represented by elements of the Xenodontomys ellipticus Range Zone in the lower QS basin and by elements of the Eumysops laeviplicatus Range Zone in the middle QS basin.

Urban dust in the Guanzhong basin of China, part II: A case study of urban dust pollution using the WRF-Dust model.

PubMed

Li, Nan; Long, Xin; Tie, Xuexi; Cao, Junji; Huang, Rujin; Zhang, Rong; Feng, Tian; Liu, Suixin; Li, Guohui

2016-01-15

We developed a regional dust dynamical model (WRF-Dust) to simulate surface dust concentrations in the Guanzhong (GZ) basin of China during two typical dust cases (19th Aug. and 26th Nov., 2013), and compared model results with the surface measurements at 17 urban and rural sites. The important improvement of the model is to employ multiple high-resolution (0.5-500 m) remote sensing data to construct dust sources. The new data include the geographic information of constructions, croplands, and barrens over the GZ basin in summer and winter of 2013. For the first time, detailed construction dust emissions have been introduced in a regional dust model in large cities of China. Our results show that by including the detailed dust sources, model performance at simulating dust pollutions in the GZ basin is significantly improved. For example, the simulated dust concentration average for the 17 sites increases from 28 μg m(-3) to 59 μg m(-3), closing to the measured concentration of 66 μg m(-3). In addition, the correlation coefficient (r) between the calculated and measured dust concentrations is also improved from 0.17 to 0.57, suggesting that our model better presents the spatial variation. Further analysis shows that urban construction activities are the crucial source in controlling urban dust pollutions. It should be considered by policy makers for mitigating particulate air pollution in many Chinese cities. Copyright © 2015 Elsevier B.V. All rights reserved.

Numerical explorations of R. M. Goodwin's business cycle model.

PubMed

Jakimowicz, Aleksander

2010-01-01

Goodwin's model, which was formulated in , still attracts economists' attention. The model possesses numerous interesting properties that have been discovered only recently due to the development of the chaos theory and the complexity theory. The first numerical explorations of the model were conducted in the early s by Strotz, McAnulty and Naines (1953). They discovered the coexistence of attractors that are well-known today, two properties of chaotic systems: the sensitive dependence on the initial conditions and the sensitive dependence on parameters. The occurrence of periodic and chaotic attractors is dependent on the value of parameters in a system. In case of certain parametric values fractal basin boundaries exist which results in enormous system sensitivity to external noise. If periodic attractors are placed in the neighborhood of the fractal basin boundaries, then even a low external noise can move the trajectory into the region in which the basin's structure is tangled. This leads to a kind of movement that resembles a chaotic movement on a strange attractor. In Goodwin's model, apart from typical chaotic behavior, there exists yet another kind of complex movements - transient chaotic behavior that is caused by the occurrence of invariant chaotic sets that are not attracting. Such sets are represented by chaotic saddles. Some of the latest observation methods of trajectories lying on invariant chaotic sets that are not attracting are straddle methods. This article provides examples of the basin boundary straddle trajectory and the saddle straddle trajectory. These cases were studied by Lorenz and Nusse (2002). I supplement the results they acquired with calculations of capacity dimension and correlation dimension.

Linking Theory to Practice: A Case Study of Pupils' Course Work on Freshwater Pollution

ERIC Educational Resources Information Center

Osterlind, Karolina; Hallden, Ola

2007-01-01

The paper reports on a study of five pupils' (13-14 years old) learning about freshwater pollution and related theoretical concepts such as drainage basin and water pollution. Much of the instruction is devoted to fieldwork conducted at a polluted lake and other practical activities designed to promote the pupils' understanding of the central…

Parameter regionalisation methods for a semi-distributed rainfall-runoff model: application to a Northern Apennine region

NASA Astrophysics Data System (ADS)

Neri, Mattia; Toth, Elena

2017-04-01

The study presents the implementation of different regionalisation approaches for the transfer of model parameters from similar and/or neighbouring gauged basin to an ungauged catchment, and in particular it uses a semi-distributed continuously-simulating conceptual rainfall-runoff model for simulating daily streamflows. The case study refers to a set of Apennine catchments (in the Emilia-Romagna region, Italy), that, given the spatial proximity, are assumed to belong to the same hydrologically homogeneous region and are used, alternatively, as donors and regionalised basins. The model is a semi-distributed version of the HBV model (TUWien model) in which the catchment is divided in zones of different altitude that contribute separately to the total outlet flow. The model includes a snow module, whose application in the Apennine area has been, so far, very limited, even if snow accumulation and melting phenomena do have an important role in the study basins. Two methods, both widely applied in the recent literature, are applied for regionalising the model: i) "parameters averaging", where each parameter is obtained as a weighted mean of the parameters obtained, through calibration, on the donor catchments ii) "output averaging", where the model is run over the ungauged basin using the entire set of parameters of each donor basin and the simulated outputs are then averaged. In the first approach, the parameters are regionalised independently from each other, in the second one, instead, the correlation among the parameters is maintained. Since the model is a semi-distributed one, where each elevation zone contributes separately, the study proposes to test also a modified version of the second approach ("output averaging"), where each zone is considered as an autonomous entity, whose parameters are transposed to the ungauged sub-basin corresponding to the same elevation zone. The study explores also the choice of the weights to be used for averaging the parameters (in the "parameters averaging" approach) or for averaging the simulated streamflow (in the "output averaging" approach): in particular, weights are estimated as a function of the similarity/distance of the ungauged basin/zone to the donors, on the basis of a set of geo-morphological catchment descriptors. The predictive accuracy of the different regionalisation methods is finally assessed by jack-knife cross-validation against the observed daily runoff for all the study catchments.

Determination of Cenozoic sedimentary structures using integrated geophysical surveys: A case study in the Barkol Basin, Xinjiang, China

NASA Astrophysics Data System (ADS)

Sun, Kai; Chen, Chao; Du, Jinsong; Wang, Limin; Lei, Binhua

2018-01-01

Thickness estimation of sedimentary basin is a complex geological problem, especially in an orogenic environment. Intense and multiple tectonic movements and climate changes result in inhomogeneity of sedimentary layers and basement configurations, which making sedimentary structure modelling difficult. In this study, integrated geophysical methods, including gravity, magnetotelluric (MT) sounding and electrical resistivity tomography (ERT), were used to estimate basement relief to understand the geological structure and evolution of the eastern Barkol Basin in China. This basin formed with the uplift of the eastern Tianshan during the Cenozoic. Gravity anomaly map revealed the framework of the entire area, and ERT as well as MT sections reflected the geoelectric features of the Cenozoic two-layer distribution. Therefore, gravity data, constrained by MT, ERT and boreholes, were utilized to estimate the spatial distribution of the Quaternary layer. The gravity effect of the Quaternary layer related to the Tertiary layer was later subtracted to obtain the residual anomaly for inversion. For the Tertiary layer, the study area was divided into several parts because of lateral difference of density contrasts. Gravity data were interpreted to determine the density contrast constrained by the MT results. The basement relief can be verified by geological investigation, including the uplift process and regional tectonic setting. The agreement between geophysical survey and prior information from geology emphasizes the importance of integrated geophysical survey as a complementary means of geological studies in this region.

Impact of recent land use and climate changes on sediment and pollutant redistribution in small catchments within the Seim River Basin (Kursk Region, European Russia)

NASA Astrophysics Data System (ADS)

Belyaev, Vladimir; Ivanova, Nadezda; Ivanov, Maxim; Bondarev, Valery; Lugovoy, Nikolay; Aseeva, Elena; Malyutina, Alisa

2017-04-01

It is widely accepted that changes of land use or climatic conditions can exert profound impacts on river basin sediment budgets and associated particle-bound pollutant redistribution patterns at different temporal and spatial scales. It can be especially difficult to distinguish relative importance of particular factors when the changes occur more or less within the same time frame. Such situation is typical for most parts of the agricultural belt of Russia, as period of economic downfall associated with collapse of the former Soviet Union and later gradual recovery practically coincides with period of the most significant climate changes observed in the late 20th - early 21st Centuries. Therefore it seems interesting and important to consider possible changes of fluvial systems responses within the period from 1980s to the present under different spatial scales. Here we plan to present results of the almost 10-year period of investigations of sediment and associated pollutant redistribution spatial and temporal patterns in several small catchments within the Seim River Basin (Kursk Region, European Russia). Studies dealt with small catchments and small river basins in scales from 1-2 km2 to 200 km2 located in different parts of the main basin. Works carried out included detailed geomorphic surveys, soil and sediment sections and cores description and sampling in different locations (undisturbed, erosion, transit, deposition), remote sensing data and morphometric analysis, soil erosion modeling. Integration of the results allowed constructing sediment budgets, in most cases, for two time intervals (approximately - pre-1986 and post-1986, as the Chernobyl-derived 137Cs has been an important time mark at all the case study sites). It has been found out that combination of several major tendencies including abandonment and recultivation of arable fields, notable decrease of winter-frozen topsoil layer thickness and increase of heavy summer rainstorms magnitude and frequency are responsible for the observed variability of sediment and associated contaminant redistribution patterns.

Beyond water, beyond boundaries: spaces of water management in the Krishna river basin, South India.

PubMed

Venot, Jean-Philippe; Bharati, Luna; Giordano, Mark; Molle, François

2011-01-01

As demand and competition for water resources increase, the river basin has become the primary unit for water management and planning. While appealing in principle, practical implementation of river basin management and allocation has often been problematic. This paper examines the case of the Krishna basin in South India. It highlights that conflicts over basin water are embedded in a broad reality of planning and development where multiple scales of decisionmaking and non-water issues are at play. While this defines the river basin as a disputed "space of dependence", the river basin has yet to acquire a social reality. It is not yet a "space of engagement" in and for which multiple actors take actions. This explains the endurance of an interstate dispute over the sharing of the Krishna waters and sets limits to what can be achieved through further basin water allocation and adjudication mechanisms – tribunals – that are too narrowly defined. There is a need to extend the domain of negotiation from that of a single river basin to multiple scales and to non-water sectors. Institutional arrangements for basin management need to internalise the political spaces of the Indian polity: the states and the panchayats. This re-scaling process is more likely to shape the river basin as a space of engagement in which partial agreements can be iteratively renegotiated, and constitute a promising alternative to the current interstate stalemate.

Using AMS to Help Interpret Glaciogenic Deposits of the Late Paleozoic Ice Age in the Parana Basin, Brazil

NASA Astrophysics Data System (ADS)

Amato, James Anthony

The term 'diamictite' is used as a lithologic descriptive term without assigning a particular origin to a rock unit as either glacial deposits (till), proglacial, glacially influenced deposits (resulting from meltwater plumes and ice rafted debris), or mass transport deposits (glacial or non-glacial related). While in some cases, it is possible to delineate between the origins of diamictites, in other instances, weathering and lack of exposures make it difficult to determine. In general, the occurrence of diamictites within the Gondwana succession has been traditionally used to indicate the occurrence of subglacial deposition despite the potential occurrence of other depositional modes. Thus, the extent of glaciation during the Late Paleozoic Ice Age is interpreted to be much greater than it actually was. . One area of interest in Gondwana where interpretation of these deposits is problematic, and hence has resulted in problems determining ice extent, is the Parana Basin in Brazil. The ability to better differentiate subglacial processes from proglacial, subaqueous mass transport, glaciomarine/glaciolacustrine rainout, and/or ice rafting, in addition to determining glacier flow or mass transport directions, will allow researchers studying these deposits to more accurately reconstruct the environments timing and extent of glaciation during the LPIA. In sedimentary fabrics, anisotropy of magnetic susceptibility (AMS) is a geophysical method, which depicts the preferred orientation of magnetic particles during the final stages of transport and/or synsedimentary deformation. The technique is used to determine the preferred orientation of the constituent grains, therefore a useful indicator to help determine the mode of deposition, direction of sediment transport, and the nature of stress and strain during deformation. In August of 2016, samples were collected from deposits assigned to the Itarare Group, which outcrop along the southern and eastern margins of the Parana Basin, Brazil. 19 fabrics were analyzed from seven different locations (Alfredo Wagner, Aurora, Cachoeira do Sul, Campo do Tenente, Ibare, Porto Amazonas, and Sao Gabriel), stretching across the states of Rio Grande do Sul, Santa Catarina, and Parana. While in most cases, AMS allowed us to delineate between the origins of diamictites, in other cases, it proved to be more difficult. In most cases, AMS measurements were beneficial in determining the direction of sediment transport. Our findings are consistent with past studies in which AMS was used to infer a variety of glaciogenic deposits, but also acts as a study case for the different types of fabrics that may develop as a result of Newtonian vs non-Newtonian sediment gravity flows. While flow directions along the southern margin of the basin are consistent with the inferred N/NW ice movement into the basin, some of the flow directions along the eastern margin are not, revealing deviations in topography. Flow directions obtained from mass transport deposits in the area stretching from Campo do Tenente to Porto Amazonas (an area in which different stratigraphic levels of glaciation are exposed) tend to show uniform flow to the south. This observation is consistent with other AMS studies of similar deposits within the area, suggesting the existence of a southward paleoslope, which strongly influenced subaqueous deposition throughout the extent of the Itarare Group.

Geologic Sequestration of CO2: Potential Permeability Changes in Host Formations of the San Juan Basin, New Mexico

NASA Astrophysics Data System (ADS)

Abel, A. P.; McPherson, B.; Lichtner, P.; Bond, G.; Stringer, J.; Grigg, R.

2002-12-01

Terrestrial sequestration through injection into geologic formations is one proposed method for the isolation of anthropogenic CO2 from the atmosphere. A variety of physical and chemical processes are known to occur both during and after geologic CO2 injection, including diagenetic chemical reactions and associated permeability changes. Although it is commonly assumed that CO2 sequestered in this way will ultimately become mineralized, the rates of these changes, including CO2 hydration in brines, are known to be relatively slow. Bond and others (this volume) have developed a biomimetic approach to CO2 sequestration, in which the rate of CO2 hydration is accelerated by the use of a biological catalyst. Together with the hydrated CO2, cations from produced brines may be used to form solid-state carbonate minerals at the earth's surface, or this bicarbonate solution may be reinjected for geologic sequestration. Chemical composition of produced brines will affect both the diagenetic reactions that occur within the host formation, and the precipitation reactions that will occur above ground. In a specific case study of the San Juan Basin, New Mexico, we are cataloging different brines present in that basin. We are using this information to facilitate evaluation of potential applications of the biomimetic process and geologic sequestration. In a separate collaborative study by Grigg and others (this volume), laboratory experiments have been conducted on multiphase CO2 and brine injection and flow through saturated rock cores. We are extending from that study to our specific case study of the San Juan basin, to examine and characterize potential permeability changes associated with accelerated diagenesis due to the presence of high concentrations of CO2 or bicarbonate solutions in situ. We are developing and conducting new laboratory experiments to evaluate relative permeability (to CO2 and brine) of selected strata from the Fruitland Formation and Pictured Cliffs Sandstone. In addition to relative permeability, we are conducting longer-term flow tests reflecting marked permeability changes, and documenting the changes by comparing detailed pre-test measurements of porosity and permeability to post-test measurements. We are using these experimental results to parameterize coupled-flow and reactive-chemistry models of a selected cross-section of the San Juan basin. Our flow and chemistry model is based on the Los Alamos National Laboratory reactive chemistry simulator, TRANS, coupled to the Lawrence Berkeley Laboratory flow simulator, TOUGH2. The purpose of these simulation models is to evaluate potential CO2- and bicarbonate-induced diagenetic changes in permeability and flow at the basin-scale. In addition they will provide useful information in relation to brine extraction. We are also using these calibrated basin models to examine natural diagenesis and permeability evolution associated with changing brine properties and flow conditions over geologic time.

Middle Rio Grande Basin Research Report 2008

Treesearch

Deborah M. Finch; Catherine Dold

2008-01-01

An ecosystem is rarely static. A natural system composed of plants, animals, and microorganisms interacting with an area's physical factors, an ecosystem is always fluctuating and evolving. But sometimes, often at the hands of humans, ecosystems change too much. Such is the case with many of the ecosystems of the Middle Rio Grande Basin of New Mexico.

Groundwater methane in relation to oil and gas development and shallow coal seams in the Denver-Julesburg Basin of Colorado

PubMed Central

Sherwood, Owen A.; Rogers, Jessica D.; Lackey, Greg; Burke, Troy L.; Osborn, Stephen G.; Ryan, Joseph N.

2016-01-01

Unconventional oil and gas development has generated intense public concerns about potential impacts to groundwater quality. Specific pathways of contamination have been identified; however, overall rates of contamination remain ambiguous. We used an archive of geochemical data collected from 1988 to 2014 to determine the sources and occurrence of groundwater methane in the Denver-Julesburg Basin of northeastern Colorado. This 60,000-km2 region has a 60-y-long history of hydraulic fracturing, with horizontal drilling and high-volume hydraulic fracturing beginning in 2010. Of 924 sampled water wells in the basin, dissolved methane was detected in 593 wells at depths of 20–190 m. Based on carbon and hydrogen stable isotopes and gas molecular ratios, most of this methane was microbially generated, likely within shallow coal seams. A total of 42 water wells contained thermogenic stray gas originating from underlying oil and gas producing formations. Inadequate surface casing and leaks in production casing and wellhead seals in older, vertical oil and gas wells were identified as stray gas migration pathways. The rate of oil and gas wellbore failure was estimated as 0.06% of the 54,000 oil and gas wells in the basin (lower estimate) to 0.15% of the 20,700 wells in the area where stray gas contamination occurred (upper estimate) and has remained steady at about two cases per year since 2001. These results show that wellbore barrier failure, not high-volume hydraulic fracturing in horizontal wells, is the main cause of thermogenic stray gas migration in this oil- and gas-producing basin. PMID:27402747

The impact of poor governance on water and sediment quality: a case study in the Pitimbu River, Brazil

NASA Astrophysics Data System (ADS)

Moreira, L.; Adamowski, J.; Gaskin, S.; Saraiva, A.

2014-09-01

Applying a collaborative approach under a power-sharing institutional structure, coupled with a shift in paradigms, sustainable water resources management often requires political-institutional reform to achieve its goals. Most of Brazil's river basins are subject to rapid urbanization; however, basin stakeholders generally lack sufficient institutional capacity to address the attending water resource issues. Subject to urbanisation, the Pitimbu River basin supplies potable water to approximately 280 000 people in Brazil's Natal region. This study investigated how current institutional models influence both water management and fluvial contamination by metals. Sediment samples collected at eight sites along the river revealed elevated levels of Pb, Fe, Al, Ni and Zn, whose sources were linked to industries, vehicles, as well as agricultural and construction wastes. Aluminium enrichment of surface waters was mainly linked to inadequate sanitation infrastructure. In light of this, the region's poor institutional capacity must be addressed through institutional reform, including a new management structure open to public collective water management planning. In so doing, Brazil's water policies should acknowledge capacity building as a critical element of institutional reform.

Spatial analysis of groundwater electrical conductivity using ordinary kriging and artificial intelligence methods (Case study: Maharlu-Bakhtegan and Tashk salt lakes basin, Iran)

NASA Astrophysics Data System (ADS)

Ghader, Fatemeh; Aljoumani, Basem; Tröger, Uwe

2017-04-01

The main resources of fresh water are the groundwater. In Iran, the quality and quantity of groundwater is affected significantly by rapid population growth and unsustainable water management in the agricultural and industrial sectors. in Maharlu-Bakhtegan and Tashk salt lakes basin, the overexploitation of groundwater for irrigation purpose caused the salt water intrusion from the lakes to the area's aquifers, moreover, the basin is located in south of Iran with semiarid climate, faces a significant decline in rainfall. All these reasons cause the degradation of ground water quality. For this study, geographical coordinates of 406 observation wells will be defined as inputs and groundwater electrical conductivities (EC) will be set as output. Ordinary kriging (OK) and artificial neural networks (ANN) will be investigated for modeling groundwater salinity. Eighty percent of data will be randomly selected to train and develop mentioned models and twenty percent of data will be used for testing and validating. Finally, the outputs of models will be compared with the corresponding measured values in observation wells.

Estimation of reservoir inflow in data scarce region by using Sacramento rainfall runoff model - A case study for Sittaung River Basin, Myanmar

NASA Astrophysics Data System (ADS)

Myo Lin, Nay; Rutten, Martine

2017-04-01

The Sittaung River is one of four major rivers in Myanmar. This river basin is developing fast and facing problems with flood, sedimentation, river bank erosion and salt intrusion. At present, more than 20 numbers of reservoirs have already been constructed for multiple purposes such as irrigation, domestic water supply, hydro-power generation, and flood control. The rainfall runoff models are required for the operational management of this reservoir system. In this study, the river basin is divided into (64) sub-catchments and the Sacramento Soil Moisture Accounting (SAC-SMA) models are developed by using satellite rainfall and Geographic Information System (GIS) data. The SAC-SMA model has sixteen calibration parameters, and also uses a unit hydrograph for surface flow routing. The Sobek software package is used for SAC-SMA modelling and simulation of river system. The models are calibrated and tested by using observed discharge and water level data. The statistical results show that the model is applicable to use for data scarce region. Keywords: Sacramento, Sobek, rainfall runoff, reservoir

Linking Governance to Sustainable Management Outcomes: Applying Dynamic Indicator Profiles to River Basin Organization Case Studies around the World.

NASA Astrophysics Data System (ADS)

Wei, Y.; Bouckaert, F. W.

2017-12-01

Institutional best practice for integrated river basin management advocates the river basin organisation (RBO) model as pivotal to achieve sustainable management outcomes and stakeholder engagement. The model has been widely practiced in transboundary settings and is increasingly adopted at national scales, though its effectiveness remains poorly studied. A meta-analysis of four river basins has been conducted to assess governance models and linking it to evaluation of biophysical management outcomes. The analysis is based on a Theory of Change framework, and includes functional dynamic governance indicator profiles, coupled to sustainable ecosystem management outcome profiles. The governance and outcome profiles, informed by context specific indicators, demand that targets for setting objectives are required in multiple dimensions, and trajectory outlines are a useful tool to track progress along the journey mapped out by the Theory of Change framework. Priorities, trade-offs and objectives vary in each basin, but the diagnostics tool allows comparison between basins in their capacity to reach targets through successive evaluations. The distance between capacity and target scores determines how program planning should be prioritized and resources allocated for implementation; this is a dynamic process requiring regular evaluations and adaptive management. The findings of this study provide a conceptual framework for combining dimensions of integrated water management principles that bridge tensions between (i) stakeholder engagement and participatory management (bottom-up approach) using localized knowledge and (ii) decision-making, control-and-command, system-scale, accountable and equitable management (top-down approach).The notion of adaptive management is broadened to include whole-of-program learnings, rather than single hypothesis based learning adjustments. This triple loop learning combines exploitative methods refinement with explorative evaluation of underlying paradigms. The significance of these findings suggests that in order to achieve effective management outcomes, a framework is required that combines governance performance with evaluations of bio-physical outcomes.

Geologic framework for the national assessment of carbon dioxide storage resources: Alaska North Slope and Kandik Basin, Alaska: Chapter I in Geologic framework for the national assessment of carbon dioxide storage resources

USGS Publications Warehouse

Craddock, William H.; Buursink, Marc L.; Covault, Jacob A.; Brennan, Sean T.; Doolan, Colin A.; Drake II, Ronald M.; Merrill, Matthew D.; Roberts-Ashby, Tina L.; Slucher, Ernie R.; Warwick, Peter D.; Blondes, Madalyn S.; Freeman, P.A.; Cahan, Steven N.; DeVera, Christina A.; Lohr, Celeste D.; Warwick, Peter D.; Corum, Margo D.

2014-01-01

For each SAU in both of the basins, we discuss the areal distribution of suitable CO2 sequestration reservoir rock. We also characterize the overlying sealing unit and describe the geologic characteristics that influence the potential CO2 storage volume and reservoir performance. These characteristics include reservoir depth, gross thickness, net thickness, porosity, permeability, and groundwater salinity. Case-by-case strategies for estimating the pore volume existing within structurally and (or) stratigraphically closed traps are presented. Although assessment results are not contained in this report, the geologic information included herein was employed to calculate the potential storage volume in the various SAUs. Lastly, in this report, we present the rationale for not conducting assessment work in fifteen sedimentary basins distributed across the Alaskan interior and within Alaskan State waters.

ASSESSING THE RELATIVE AND COMBINED IMPACTS OF FUTURE LAND-USE AND CLIMATE CHANGES ON NONPOINT SOURCE POLLUTION

EPA Science Inventory

In this paper, we discuss the potential water quality impacts of future land-use and climate changes. The Little Miami River Basin was used as a case study. It is a predominantly agricultural watershed in southwestern Ohio (U.S.A.) that has experienced land-use modifications. ...

Inferring time-varying recharge from inverse analysis of long-term water levels

NASA Astrophysics Data System (ADS)

Dickinson, Jesse E.; Hanson, R. T.; Ferré, T. P. A.; Leake, S. A.

2004-07-01

Water levels in aquifers typically vary in response to time-varying rates of recharge, suggesting the possibility of inferring time-varying recharge rates on the basis of long-term water level records. Presumably, in the southwestern United States (Arizona, Nevada, New Mexico, southern California, and southern Utah), rates of mountain front recharge to alluvial aquifers depend on variations in precipitation rates due to known climate cycles such as the El Niño-Southern Oscillation index and the Pacific Decadal Oscillation. This investigation examined the inverse application of a one-dimensional analytical model for periodic flow described by Lloyd R. Townley in 1995 to estimate periodic recharge variations on the basis of variations in long-term water level records using southwest aquifers as the case study. Time-varying water level records at various locations along the flow line were obtained by simulation of forward models of synthetic basins with applied sinusoidal recharge of either a single period or composite of multiple periods of length similar to known climate cycles. Periodic water level components, reconstructed using singular spectrum analysis (SSA), were used to calibrate the analytical model to estimate each recharge component. The results demonstrated that periodic recharge estimates were most accurate in basins with nearly uniform transmissivity and the accuracy of the recharge estimates depends on monitoring well location. A case study of the San Pedro Basin, Arizona, is presented as an example of calibrating the analytical model to real data.

Turbidity and nitrate transfer in karstic aquifers in rural areas: the Brionne Basin case-study.

PubMed

Nebbache, S; Feeny, V; Poudevigne, I; Alard, D

2001-08-01

The degradation of water quality in many groundwaters of Europe is a major source of concern. Rises in turbidity and nitrate concentrations represent present or potential threats for the quality of drinking water in rural areas. They are for the most part a consequence of agricultural intensification which has considerably affected land cover and land use in recent decades. In our case-study (a karstic catchment) the mechanisms which explain changes in water quality, as far as turbidity and nitrate are concerned, result from a strong continuity between surface and underground waters. The karstic system of the Brionne Basin can be considered as both the focus of rapid horizontal flows (runoff, a rapid process in which rainwater reaches the spring directly through sinkholes) and slow vertical flows (leaching, in which rainwater filters through the soil to the spring). A hierarchical approach to the water pollution problem of the basin suggests that turbidity or nitrate concentrations peak during heavy rain episodes and are short-term events. In terms of management, this implies that the solution to water pollution caused by such events is also short-term and can therefore be addressed at a local scale. The rise of nitrate concentrations during the past twenty years is the main concern. The solution can only be found at a global scale (all the catchment area must be taken in account: land plots and their spatial configuration), and by taking a long-term approach.

Inferring time‐varying recharge from inverse analysis of long‐term water levels

USGS Publications Warehouse

Dickinson, Jesse; Hanson, R.T.; Ferré, T.P.A.; Leake, S.A.

2004-01-01

Water levels in aquifers typically vary in response to time‐varying rates of recharge, suggesting the possibility of inferring time‐varying recharge rates on the basis of long‐term water level records. Presumably, in the southwestern United States (Arizona, Nevada, New Mexico, southern California, and southern Utah), rates of mountain front recharge to alluvial aquifers depend on variations in precipitation rates due to known climate cycles such as the El Niño‐Southern Oscillation index and the Pacific Decadal Oscillation. This investigation examined the inverse application of a one‐dimensional analytical model for periodic flow described by Lloyd R. Townley in 1995 to estimate periodic recharge variations on the basis of variations in long‐term water level records using southwest aquifers as the case study. Time‐varying water level records at various locations along the flow line were obtained by simulation of forward models of synthetic basins with applied sinusoidal recharge of either a single period or composite of multiple periods of length similar to known climate cycles. Periodic water level components, reconstructed using singular spectrum analysis (SSA), were used to calibrate the analytical model to estimate each recharge component. The results demonstrated that periodic recharge estimates were most accurate in basins with nearly uniform transmissivity and the accuracy of the recharge estimates depends on monitoring well location. A case study of the San Pedro Basin, Arizona, is presented as an example of calibrating the analytical model to real data.

The effect of drainage reorganization on paleoaltimetry studies: An example from the Paleogene Laramide foreland

NASA Astrophysics Data System (ADS)

Davis, Steven J.; Wiegand, Bettina A.; Carroll, Alan R.; Chamberlain, C. Page

2008-11-01

Using multiple isotope systems, we examine the complex effects of drainage reorganization in the Laramide Foreland in the context of stable isotope paleoaltimetry. Strontium, oxygen and carbon isotopic data from lacustrine carbonates formed in the southwestern Uinta Basin, Utah between the Late Cretaceous and late Middle Eocene reveal a two stage expansion in the drainage basin of Lake Uinta beginning at ~ 53 Ma culminating in the Mahogany highstand at 48.6 Ma. A marked increase in 87Sr/ 86Sr ratios of samples from the Main Body of the Green River Formation is interpreted as the result of water overflowing the Greater Green River Basin in Wyoming and entering Lake Uinta from the east via the Piceance Creek Basin of northwestern Colorado. This large new source of water caused a rapid expansion of Lake Uinta and was accompanied by a significant and rapid increase in the O isotope record of carbonate samples by ~ 6‰. The periodic overspilling of Lake Gosiute probably became continuous at ~ 49 Ma, when the lake captured low- δ18O water from the Challis and Absaroka Volcanic Fields to the north. However, evaporation in the Greater Green River and Piceance Creek Basins meant that the waters entering Lake Uinta were still enriched in 18O. By ~ 46 Ma, inflows from the Greater Green River Basin ceased, resulting in a lowstand of Lake Uinta and the deposition of bedded evaporites in the Saline Facies of the Green River Formation. We thus show that basin development and lake hydrology in the Laramide foreland were characterized by large-scale changes in Cordilleran drainage patterns, capable of confounding paleoaltimetry studies premised on too few isotopic systems, samples or localities. In the case of the North American Cordillera of the Paleogene, we further demonstrate the likelihood that (1) topographic evolution of distal source areas strongly influenced the isotopic records of intraforeland basins and (2) a pattern of drainage integration between the hinterland and foreland may correlate in space and time with the southward sweep of hinterland magmatism.

A paleolatitude approach to assessing surface temperature history for use in burial heating models

USGS Publications Warehouse

Barker, Charles E.

2000-01-01

Calculations using heat flow theory as well as case histories show that over geologic time scales (106 years), changes in mean annual surface temperature (Ts) on the order of 10°C penetrate kilometers deep into the crust. Thus, burial heating models of sedimentary basins, which typically span kilometers in depth and persist over geological time frames, should consider Ts history to increase their accuracy. In any case, Ts history becomes important when it changes enough to be detected by a thermal maturation index like vitrinite reflectance, a parameter widely used to constrain burial heating models. Assessment of the general temperature conditions leading to petroleum generation indicates that changes in Ts as small as 6°C can be detected by vitrinite reflectance measurements. This low temperature threshold indicates that oil and gas windows can be significantly influenced by Ts history. A review of paleoclimatic factors suggests the significant and geologically resolvable factors affecting Ts history are paleolatitude, long-term changes between cool and warm geological periods (climate mode), the degree to which a basin is removed from the sea (geographic isolation), and elevation or depth relative to sea level. Case studies using geologically realistic data ranges or different methods of estimating Ts in a burial heating model indicate a significant impact of Ts when: (1) continental drift, subduction, tectonism and erosion significantly change paleolatitude, paleoaltitude, or paleogeography; (2) strata are at, or near, maximum burial, and changes in Ts directly influence maximum burial temperature; and (3), when a significant change in Ts occurs near the opening or closing of the oil or gas windows causing petroleum generation to begin or cease. Case studies show that during the burial heating and petroleum generation phase of basin development changes in climate mode alone can influence Ts by about 15°C. At present, Ts changes from the poles to the equator by about 50°C. Thus, in extreme cases, continental drift alone can seemingly produce Ts changes on the order of 50°C over a time frame of 107 years.

Hydrogeomorphic and ecological control on carbonate dissolution in a patterned landscape in South Florida

NASA Astrophysics Data System (ADS)

Dong, X.; Heffernan, J. B.; Murray, A. B.; Cohen, M. J.; Martin, J. B.

2016-12-01

The evolution of the critical zone both shapes and reflects hydrologic, geochemical, and ecological processes. These interactions are poorly understood in karst landscapes with highly soluble bedrock. In this study, we used the regular-dispersed wetland basins of Big Cypress National Preserve in Florida as a focal case to model the hydrologic, geochemical, and biological mechanisms that affect soil development in karst landscapes. We addressed two questions: (1) What is the minimum timescale for wetland basin development, and (2) do changes in soil depth feed back on dissolution processes and if so by what mechanism? We developed an atmosphere-water-soil model with coupled water-solute transport, incorporating major ion equilibria and kinetic non-equilibrium chemistry, and biogenic acid production via roots distributed through the soil horizon. Under current Florida climate, weathering to a depth of 2 m (a typical depth of wetland basins) would take 4000 6000 yrs, suggesting that landscape pattern could have origins as recent as the most recent stabilization of sea level. Our model further illustrates that interactions between ecological and hydrologic processes influence the rate and depth-dependence of weathering. Absent inundation, dissolution rate decreased exponentially with distance from the bedrock to groundwater table. Inundation generally increased bedrock dissolution, but surface water chemistry and residence time produced complex and non-linear effects on dissolution rate. Biogenic acidity accelerated the dissolution rate by 50 and 1,000 times in inundated and exposed soils. Phase portrait analysis indicated that exponential decreases in bedrock dissolution rate with soil depth could produce stable basin depths. Negative feedback between hydro-period and total basin volume could stabilize the basin radius, but the lesser strength of this mechanism may explain the coalescence of wetland basins observed in some parts of the Big Cypress Landscape.

Dynamical Approach Study of Spurious Steady-State Numerical Solutions of Nonlinear Differential Equations. Part 2; Global Asymptotic Behavior of Time Discretizations

NASA Technical Reports Server (NTRS)

Yee, H. C.; Sweby, P. K.

1995-01-01

The global asymptotic nonlinear behavior of 11 explicit and implicit time discretizations for four 2 x 2 systems of first-order autonomous nonlinear ordinary differential equations (ODEs) is analyzed. The objectives are to gain a basic understanding of the difference in the dynamics of numerics between the scalars and systems of nonlinear autonomous ODEs and to set a baseline global asymptotic solution behavior of these schemes for practical computations in computational fluid dynamics. We show how 'numerical' basins of attraction can complement the bifurcation diagrams in gaining more detailed global asymptotic behavior of time discretizations for nonlinear differential equations (DEs). We show how in the presence of spurious asymptotes the basins of the true stable steady states can be segmented by the basins of the spurious stable and unstable asymptotes. One major consequence of this phenomenon which is not commonly known is that this spurious behavior can result in a dramatic distortion and, in most cases, a dramatic shrinkage and segmentation of the basin of attraction of the true solution for finite time steps. Such distortion, shrinkage and segmentation of the numerical basins of attraction will occur regardless of the stability of the spurious asymptotes, and will occur for unconditionally stable implicit linear multistep methods. In other words, for the same (common) steady-state solution the associated basin of attraction of the DE might be very different from the discretized counterparts and the numerical basin of attraction can be very different from numerical method to numerical method. The results can be used as an explanation for possible causes of error, and slow convergence and nonconvergence of steady-state numerical solutions when using the time-dependent approach for nonlinear hyperbolic or parabolic PDEs.

Dynamical Approach Study of Spurious Steady-State Numerical Solutions of Nonlinear Differential Equations. 2; Global Asymptotic Behavior of Time Discretizations; 2. Global Asymptotic Behavior of time Discretizations

NASA Technical Reports Server (NTRS)

Yee, H. C.; Sweby, P. K.

1995-01-01

The global asymptotic nonlinear behavior of 1 1 explicit and implicit time discretizations for four 2 x 2 systems of first-order autonomous nonlinear ordinary differential equations (ODES) is analyzed. The objectives are to gain a basic understanding of the difference in the dynamics of numerics between the scalars and systems of nonlinear autonomous ODEs and to set a baseline global asymptotic solution behavior of these schemes for practical computations in computational fluid dynamics. We show how 'numerical' basins of attraction can complement the bifurcation diagrams in gaining more detailed global asymptotic behavior of time discretizations for nonlinear differential equations (DEs). We show how in the presence of spurious asymptotes the basins of the true stable steady states can be segmented by the basins of the spurious stable and unstable asymptotes. One major consequence of this phenomenon which is not commonly known is that this spurious behavior can result in a dramatic distortion and, in most cases, a dramatic shrinkage and segmentation of the basin of attraction of the true solution for finite time steps. Such distortion, shrinkage and segmentation of the numerical basins of attraction will occur regardless of the stability of the spurious asymptotes, and will occur for unconditionally stable implicit linear multistep methods. In other words, for the same (common) steady-state solution the associated basin of attraction of the DE might be very different from the discretized counterparts and the numerical basin of attraction can be very different from numerical method to numerical method. The results can be used as an explanation for possible causes of error, and slow convergence and nonconvergence of steady-state numerical solutions when using the time-dependent approach for nonlinear hyperbolic or parabolic PDES.

The Added Value of Water Footprint Assessment for National Water Policy: A Case Study for Morocco

PubMed Central

Schyns, Joep F.; Hoekstra, Arjen Y.

2014-01-01

A Water Footprint Assessment is carried out for Morocco, mapping the water footprint of different activities at river basin and monthly scale, distinguishing between surface- and groundwater. The paper aims to demonstrate the added value of detailed analysis of the human water footprint within a country and thorough assessment of the virtual water flows leaving and entering a country for formulating national water policy. Green, blue and grey water footprint estimates and virtual water flows are mainly derived from a previous grid-based (5×5 arc minute) global study for the period 1996–2005. These estimates are placed in the context of monthly natural runoff and waste assimilation capacity per river basin derived from Moroccan data sources. The study finds that: (i) evaporation from storage reservoirs is the second largest form of blue water consumption in Morocco, after irrigated crop production; (ii) Morocco’s water and land resources are mainly used to produce relatively low-value (in US$/m3 and US$/ha) crops such as cereals, olives and almonds; (iii) most of the virtual water export from Morocco relates to the export of products with a relatively low economic water productivity (in US$/m3); (iv) blue water scarcity on a monthly scale is severe in all river basins and pressure on groundwater resources by abstractions and nitrate pollution is considerable in most basins; (v) the estimated potential water savings by partial relocation of crops to basins where they consume less water and by reducing water footprints of crops down to benchmark levels are significant compared to demand reducing and supply increasing measures considered in Morocco’s national water strategy. PMID:24919194

The added value of water footprint assessment for national water policy: a case study for Morocco.

PubMed

Schyns, Joep F; Hoekstra, Arjen Y

2014-01-01

A Water Footprint Assessment is carried out for Morocco, mapping the water footprint of different activities at river basin and monthly scale, distinguishing between surface- and groundwater. The paper aims to demonstrate the added value of detailed analysis of the human water footprint within a country and thorough assessment of the virtual water flows leaving and entering a country for formulating national water policy. Green, blue and grey water footprint estimates and virtual water flows are mainly derived from a previous grid-based (5 × 5 arc minute) global study for the period 1996-2005. These estimates are placed in the context of monthly natural runoff and waste assimilation capacity per river basin derived from Moroccan data sources. The study finds that: (i) evaporation from storage reservoirs is the second largest form of blue water consumption in Morocco, after irrigated crop production; (ii) Morocco's water and land resources are mainly used to produce relatively low-value (in US$/m3 and US$/ha) crops such as cereals, olives and almonds; (iii) most of the virtual water export from Morocco relates to the export of products with a relatively low economic water productivity (in US$/m3); (iv) blue water scarcity on a monthly scale is severe in all river basins and pressure on groundwater resources by abstractions and nitrate pollution is considerable in most basins; (v) the estimated potential water savings by partial relocation of crops to basins where they consume less water and by reducing water footprints of crops down to benchmark levels are significant compared to demand reducing and supply increasing measures considered in Morocco's national water strategy.

Multi-model ensemble hydrological simulation using a BP Neural Network for the upper Yalongjiang River Basin, China

NASA Astrophysics Data System (ADS)

Li, Zhanjie; Yu, Jingshan; Xu, Xinyi; Sun, Wenchao; Pang, Bo; Yue, Jiajia

2018-06-01

Hydrological models are important and effective tools for detecting complex hydrological processes. Different models have different strengths when capturing the various aspects of hydrological processes. Relying on a single model usually leads to simulation uncertainties. Ensemble approaches, based on multi-model hydrological simulations, can improve application performance over single models. In this study, the upper Yalongjiang River Basin was selected for a case study. Three commonly used hydrological models (SWAT, VIC, and BTOPMC) were selected and used for independent simulations with the same input and initial values. Then, the BP neural network method was employed to combine the results from the three models. The results show that the accuracy of BP ensemble simulation is better than that of the single models.

Risk Assessment in Relation to the Effect of Climate Change on Water Shortage in the Taichung Area

NASA Astrophysics Data System (ADS)

Hsiao, J.; Chang, L.; Ho, C.; Niu, M.

2010-12-01

Rapid economic development has stimulated a worldwide greenhouse effect and induced global climate change. Global climate change has increased the range of variation in the quantity of regional river flows between wet and dry seasons, which effects the management of regional water resources. Consequently, the influence of climate change has become an important issue in the management of regional water resources. In this study, the Monte Carlo simulation method was applied to risk analysis of shortage of water supply in the Taichung area. This study proposed a simulation model that integrated three models: weather generator model, surface runoff model, and water distribution model. The proposed model was used to evaluate the efficiency of the current water supply system and the potential effectiveness of two additional plans for water supply: the “artificial lakes” plan and the “cross-basin water transport” plan. A first-order Markov Chain method and two probability distribution models, exponential distribution and normal distribution, were used in the weather generator model. In the surface runoff model, researchers selected the Generalized Watershed Loading Function model (GWLF) to simulate the relationship between quantity of rainfall and basin outflow. A system dynamics model (SD) was applied to the water distribution model. Results of the simulation indicated that climate change could increase the annual quantity of river flow in the Dachia River and Daan River basins. However, climate change could also increase the difference in the quantity of river flow between wet and dry seasons. Simulation results showed that in current system case or in the additional plan cases, shortage status of water for both public and agricultural uses with conditions of climate change will be mostly worse than that without conditions of climate change except for the shortage status for the public use in the current system case. With or without considering the effect of climate change, the additional plans, especially the “cross-basin water transport” plan, for water supply could significantly increase the supply of water for public use. The proposed simulation model and results of analysis in this study could provide valuable reference for decision-makers in regards to risk analysis of regional water supply.

Dilution correction equation revisited: The impact of stream slope, relief ratio and area size of basin on geochemical anomalies

NASA Astrophysics Data System (ADS)

Shahrestani, Shahed; Mokhtari, Ahmad Reza

2017-04-01

Stream sediment sampling is a well-known technique used to discover the geochemical anomalies in regional exploration activities. In an upstream catchment basin of stream sediment sample, the geochemical signals originating from probable mineralization could be diluted due to mixing with the weathering material coming from the non-anomalous sources. Hawkes's equation (1976) was an attempt to overcome the problem in which the area size of catchment basin was used to remove dilution from geochemical anomalies. However, the metal content of a stream sediment sample could be linked to several geomorphological, sedimentological, climatic and geological factors. The area size is not itself a comprehensive representative of dilution taking place in a catchment basin. The aim of the present study was to consider a number of geomorphological factors affecting the sediment supply, transportation processes, storage and in general, the geochemistry of stream sediments and their incorporation in the dilution correction procedure. This was organized through employing the concept of sediment yield and sediment delivery ratio and linking such characteristics to the dilution phenomenon in a catchment basin. Main stream slope (MSS), relief ratio (RR) and area size (Aa) of catchment basin were selected as the important proxies (PSDRa) for sediment delivery ratio and then entered to the Hawkes's equation. Then, Hawkes's and new equations were applied on the stream sediment dataset collected from Takhte-Soleyman district, west of Iran for Au, As and Sb values. A number of large and small gold, antimony and arsenic mineral occurrences were used to evaluate the results. Anomaly maps based on the new equations displayed improvement in anomaly delineation taking the spatial distribution of mineral deposits into account and could present new catchment basins containing known mineralization as the anomaly class, especially in the case of Au and As. Four catchment basins having Au and As mineralization were added to anomaly class and also one catchment basin with known As occurrence was highlighted as anomalous using new approach. The results demonstrated the usefulness of considering geomorphological parameters in dealing with dilution phenomenon in a catchment basin.

The Agost Basin (Betic Cordillera, Alicante province, Spain): a pull-apart basin involving salt tectonics

NASA Astrophysics Data System (ADS)

Martín-Martín, Manuel; Estévez, Antonio; Martín-Rojas, Ivan; Guerrera, Francesco; Alcalá, Francisco J.; Serrano, Francisco; Tramontana, Mario

2018-03-01

The Agost Basin is characterized by a Miocene-Quaternary shallow marine and continental infilling controlled by the evolution of several curvilinear faults involving salt tectonics derived from Triassic rocks. From the Serravallian on, the area experienced a horizontal maximum compression with a rotation of the maximum stress axis from E-W to N-S. The resulting deformation gave rise to a strike-slip fault whose evolution is characterized progressively by three stages: (1) stepover/releasing bend with a dextral motion of blocks; (2) very close to pure horizontal compression; and (3) restraining bend with a sinistral movement of blocks. In particular, after an incipient fracturing stage, faults generated a pull-apart basin with terraced sidewall fault and graben subzones developed in the context of a dextral stepover during the lower part of late Miocene p.p. The occurrence of Triassic shales and evaporites played a fundamental role in the tectonic evolution of the study area. The salty material flowed along faults during this stage generating salt walls in root zones and salt push-up structures at the surface. During the purely compressive stage (middle part of late Miocene p.p.) the salt walls were squeezed to form extrusive mushroom-like structures. The large amount of clayish and salty material that surfaced was rapidly eroded and deposited into the basin, generating prograding fan clinoforms. The occurrence of shales and evaporites (both in the margins of the basin and in the proper infilling) favored folding of basin deposits, faulting, and the formation of rising blocks. Later, in the last stage (upper part of late Miocene p.p.), the area was affected by sinistral restraining conditions and faults must have bent to their current shape. The progressive folding of the basin and deformation of margins changed the supply points and finally caused the end of deposition and the beginning of the current erosive systems. On the basis of the interdisciplinary results, the Agost Basin can be considered a key case of the interference between salt tectonics and the evolution of strike-slip fault zones. The reconstructed model has been compared with several scaled sandbox analogical models and with some natural pull-apart basins.

Finite Element Modelling of the Indo-Gangetic Basin to Study Site Amplification

NASA Astrophysics Data System (ADS)

Sivasubramonian, J.; Jaya, D.; Raghukanth, S. T. G.; Mai, P. M.

2017-12-01

We have developed a finite-element model of the 3D velocity structure of the Indo-Gangetic basin (IG basin) to quantify site amplifications due to seismic waves emanated from regional earthquakes. Estimating seismic wave amplifications is difficult in case of limited instrumentation, thus motivating us to propose a new simulation-based approach. The input required for the finite-element model include the spatial coordinates and the material properties (density, P-wave and S-wave velocities, Q factor) of the basin. Recent studies in the basin demarcate sediment layers of varying thickness, reaching down to a depth of 6 km and S-wave velocities ranging from 0.4-2.4 km/s (Srinivas et al., 2013). In the present study, our regional model has dimensions 900 x 900 x 80 km in x, y and z directions, discretized into 320 x 320 x 53 hexahedral elements. The top 6 km of the IG basin is divided into 8 different sediment layers with varying material properties. We use kinematic rupture models for the earthquake sources to simulate past as well as hypothetical future events. Two past earthquakes (Mw4.9, Delhi; Mw5.2, Chamoli) and two hypothetical earthquakes (Mw7.1; Mw8.5) are considered in our study. The rupture plane dimensions (L and W) and the slip distribution are estimated using the method of Mai and Beroza (2002). Based on focal-mechanism solutions and the depths of seismicity, we define the strike (580, 3090), the dip (650, 210), the rake (160, 770), and the depth of top edge of fault (5 km, 19 km) for the two large hypothetical earthquakes. Based on these parameters, the Centroid Moment Tensor (CMT) solution of the source is obtained. Ground motions are then simulated by solving the three-dimensional wave equation using the spectral element method (Komatitsch and Tromp, 1999). The key observations from our results are: 1) basin amplification factors for Peak Ground Velocity (PGV) are twice as high as Peak Ground Displacement (PGD) 2) PGV amplifications are as high as a factor of 6 for earthquakes occurring inside the basin, and a factor of 4 for Himalayan earthquakes (to the north of the study region) 3) The simulated shake maps of PGV and PGD show directivity. Based on the above observations, we conclude that it is important to include our model into low-frequency ground-motion estimation for seismic hazard analysis.

Optimization of wetland restoration siting and zoning in flood retention areas of river basins in China: A case study in Mengwa, Huaihe River Basin

NASA Astrophysics Data System (ADS)

Zhang, Xiaolei; Song, Yuqin

2014-11-01

Wetland restoration in floodplains is an ecological solution that can address basin-wide flooding issues and minimize flooding and damages to riverine and downstream areas. High population densities, large economic outputs, and heavy reliance on water resources make flood retention and management pressing issues in China. To balance flood control and sustainable development economically, socially, and politically, flood retention areas have been established to increase watershed flood storage capacities and enhance the public welfare for the populace living in the areas. However, conflicts between flood storage functions and human habitation appear irreconcilable. We developed a site-specific methodology for identifying potential sites and functional zones for wetland restoration in a flood retention area in middle and eastern China, optimizing the spatial distribution and functional zones to maximize flood control and human and regional development. This methodology was applied to Mengwa, one of 21 flood retention areas in China's Huaihe River Basin, using nine scenarios that reflected different flood, climatic, and hydraulic conditions. The results demonstrated improved flood retention and ecological functions, as well as increased economic benefits.

Key issues for determining the exploitable water resources in a Mediterranean river basin.

PubMed

Pedro-Monzonís, María; Ferrer, Javier; Solera, Abel; Estrela, Teodoro; Paredes-Arquiola, Javier

2015-01-15

One of the major difficulties in water planning is to determine the water availability in a water resource system in order to distribute water sustainably. In this paper, we analyze the key issues for determining the exploitable water resources as an indicator of water availability in a Mediterranean river basin. Historically, these territories are characterized by heavily regulated water resources and the extensive use of unconventional resources (desalination and wastewater reuse); hence, emulating the hydrological cycle is not enough. This analysis considers the Jucar River Basin as a case study. We have analyzed the different possible combinations between the streamflow time series, the length of the simulation period and the reliability criteria. As expected, the results show a wide dispersion, proving the great influence of the reliability criteria used for the quantification and localization of the exploitable water resources in the system. Therefore, it is considered risky to provide a single value to represent the water availability in the Jucar water resource system. In this sense, it is necessary that policymakers and stakeholders make a decision about the methodology used to determine the exploitable water resources in a river basin. Copyright © 2014 Elsevier B.V. All rights reserved.

Water accounting and vulnerability evaluation (WAVE): considering atmospheric evaporation recycling and the risk of freshwater depletion in water footprinting.

PubMed

Berger, Markus; van der Ent, Ruud; Eisner, Stephanie; Bach, Vanessa; Finkbeiner, Matthias

2014-04-15

Aiming to enhance the analysis of water consumption and resulting consequences along the supply chain of products, the water accounting and vulnerability evaluation (WAVE) model is introduced. On the accounting level, atmospheric evaporation recycling within drainage basins is considered for the first time, which can reduce water consumption volumes by up to 32%. Rather than predicting impacts, WAVE analyzes the vulnerability of basins to freshwater depletion. Based on local blue water scarcity, the water depletion index (WDI) denotes the risk that water consumption can lead to depletion of freshwater resources. Water scarcity is determined by relating annual water consumption to availability in more than 11,000 basins. Additionally, WDI accounts for the presence of lakes and aquifers which have been neglected in water scarcity assessments so far. By setting WDI to the highest value in (semi)arid basins, absolute freshwater shortage is taken into account in addition to relative scarcity. This avoids mathematical artifacts of previous indicators which turn zero in deserts if consumption is zero. As illustrated in a case study of biofuels, WAVE can help to interpret volumetric water footprint figures and, thus, promotes a sustainable use of global freshwater resources.

Evaluation of climate change effects on the hydrology of a medium-sized Mediterranean basin affected by data sparseness

NASA Astrophysics Data System (ADS)

Piras, Monica; Mascaro, Giuseppe; Deidda, Roberto; Vivoni, Enrique R.

2014-05-01

Many studies based on global and regional climate models agree on the prediction that the Mediterranean area will be most likely affected by climate changes with consequent reduced water availability and intensified hydrologic extremes. This study evaluates the effects of climate changes on the hydrologic response of a medium-sized Mediterranean basin through downscaling techniques and hydrologic simulations. The watershed is the Rio Mannu at Monastir basin (473 km2), located in an agricultural area of southern Sardinia, Italy, which has suffered drought issues in the last decades. It is one of the seven study cases of a multidisciplinary European research project, CLIMB (Climate Induced Changes on the Hydrology of Mediterranean Basins). In such basins, characterized by strong climate variability and by a complex hydrologic response, process based distributed hydrologic models, DHMs, combined with regional climate models, RCMs, and downscaling techniques can help in the evaluation of the local impacts of climate change on water resources decreasing the uncertainty. Since the Rio Mannu basin is affected by data sparseness (meteorological and streamflow data are collected in non overlapping time periods and at diverse time resolutions), two statistical downscaling strategies for precipitation and potential evapotranspiration have been designed which allow to obtain the high-resolution input data required for the calibration of our hydrologic model, the TIN-based Real time Integrated Basin Simulator (tRIBS). We show how the DHM has been calibrated and validated with reasonable accuracy using the disaggregation tools. Next, the same downscaling algorithms have been used to fill the resolution discrepancy between RCMs and the hydrologic model. The outputs of four RCMs, selected as the best performing and bias corrected within the CLIMB project, have been downscaled and used to force the tRIBS during a reference (1971-2000) and a future (2041-2070) period. Several hydro-climatic indicators have been computed based on the time series and spatial maps produced by the DHM to assess the variation in Rio Mannu water resources budget and hydrologic extremes in the future period as compared to the reference one. Our results confirms what is generally predicted for the Mediterranean area, showing a basin future condition of more water shortages due to both reduced precipitations and increased temperatures.

The use of AQUATOOL DSS applied to the System of Environmental-Economic Accounting for Water (SEEAW)

NASA Astrophysics Data System (ADS)

Pedro-Monzonís, María; Jiménez-Fernández, Pedro; Solera, Abel; Jiménez-Gavilán, Pablo

2016-02-01

Currently, water accounts are one of the next steps to be implemented in European River Basin Management Plans. Building water accounts is a complex task, mainly due to the lack of common European definitions and procedures. For their development, when data is not systematically measured, simulation models and estimations are necessary. The main idea of this paper is to present a new approach which enables the combined use of hydrological models and water resources models developed with AQUATOOL Decision Support System (DSS) to fill in the physical water supply and use tables and the asset accounts presented in the System of Economic and Environmental Accounts for Water (SEEAW). The case study is the Vélez River Basin, located in the southern part of the Iberian Peninsula in Spain. In addition to obtaining the physical water supply and use tables and the asset accounts in this river basin, we present here the indicators as a result thereof. These indicators cover many critical aspects of water management, showing a general description of the river basin and allowing decision-makers to characterise the pressures on water resources. As a general conclusion, the union of AQUATOOL DSS and SEEAW will provide more complete information to decision-makers and it enables to introduce these methodological decisions in order to guarantee consistency and comparability of the results between different river basins.

Natural and environmental vulnerability analysis through remote sensing and GIS techniques: a case study of Indigirka River basin, Eastern Siberia, Russia

NASA Astrophysics Data System (ADS)

Boori, Mukesh S.; Choudhary, Komal; Kupriyanov, Alexander; Sugimoto, Atsuko; Evers, Mariele

2016-10-01

The aim of this research work is to understand natural and environmental vulnerability situation and its cause such as intensity, distribution and socio-economic effect in the Indigirka River basin, Eastern Siberia, Russia. This paper identifies, assess and classify natural and environmental vulnerability using landscape pattern from multidisciplinary approach, based on remote sensing and Geographical Information System (GIS) techniques. A model was developed by following thematic layers: land use/cover, vegetation, wetland, geology, geomorphology and soil in ArcGIS 10.2 software. According to numerical results vulnerability classified into five levels: low, sensible, moderate, high and extreme vulnerability by mean of cluster principal. Results are shows that in natural vulnerability maximum area covered by moderate (29.84%) and sensible (38.61%) vulnerability and environmental vulnerability concentrated by moderate (49.30%) vulnerability. So study area has at medial level vulnerability. The results found that the methodology applied was effective enough in the understanding of the current conservation circumstances of the river basin in relation to their environment with the help of remote sensing and GIS. This study is helpful for decision making for eco-environmental recovering and rebuilding as well as predicting the future development.

Sandstone type uranium deposits in the Ordos Basin, Northwest China: A case study and an overview

NASA Astrophysics Data System (ADS)

Akhtar, Shamim; Yang, Xiaoyong; Pirajno, Franco

2017-09-01

This paper provides a comprehensive review on studies of sandstone type uranium deposits in the Ordos Basin, Northwest China. As the second largest sedimentary basin, the Ordos Basin has great potential for targeting sandstone type U mineralization. The newly found and explored Dongsheng and Diantou sandstone type uranium deposits are hosted in the Middle Jurassic Zhilou Formation. A large number of investigations have been conducted to trace the source rock compositions and relationship between lithic subarkose sandstone host rock and uranium mineralization. An optical microscopy study reveals two types of alteration associated with the U mineralization: chloritization and sericitization. Some unusual mineral structures, with compositional similarity to coffinite, have been identified in a secondary pyrite by SEM These mineral phases are proposed to be of bacterial origin, following high resolution mapping of uranium minerals and trace element determinations in situ. Moreover, geochemical studies of REE and trace elements constrained the mechanism of uranium enrichment, displaying LREE enrichment relative to HREE. Trace elements such as Pb, Mo and Ba have a direct relationship with uranium enrichment and can be used as index for mineralization. The source of uranium ore forming fluids and related geological processes have been studied using H, O and C isotope systematics of fluid inclusions in quartz veins and the calcite cement of sandstone rocks hosting U mineralization. Both H and O isotopic compositions of fluid inclusions reveal that ore forming fluids are a mixture of meteoric water and magmatic water. The C and S isotopes of the cementing material of sandstone suggest organic origin and bacterial sulfate reduction (BSR), providing an important clue for U mineralization. Discussion of the ore genesis shows that the greenish gray sandstone plays a crucial role during processes leading to uranium mineralization. Consequently, an oxidation-reduction model for sandstone-type uranium deposit is proposed, which can elucidate the source of uranium in the deposits of the Ordos Basin, based on the role of organic materials and sulfate reducing bacteria. We discuss the mechanism of uranium deposition responsible for the genesis of these large sandstone type uranium deposits in this unique sedimentary basin.

Impact of dynamically changing land cover on runoff process: the case of Iligan river basin

NASA Astrophysics Data System (ADS)

Salcedo, Stephanie Mae B.; Suson, Peter D.; Milano, Alan E.; Ignacio, Ma. Teresa T.

2016-10-01

Iligan river basin located in Northern Mindanao, Philippines covers 165.7 km2 of basin area. In December 2011, tropical storm Sendong (Washi) hit Iligan City, leaving a trail of wrecked infrastructures and about 490 persons reported dead. What transpired was a wake up call to mitigate future flood disasters. Fundamental to mitigation is understanding runoff behavior inside a basin considering that this is the main source of flooding. For this reason, the present study evaluated total runoff volume, peak discharge and lag time given land cover scenarios in four different years- 1973, 1989, 1998 and 2008. IFSAR and LIDAR DEM were integrated to generate the basin model in ArcGIS. HEC-HMS was used in simulating models for each scenario with Soil Conservation Service Curve Number (SCS CN) as the loss parameter method. Four simulation models of the runoff with varying CN values were established using RIDF as rainfall input with 5 year, 10 year, 25 year, 50 year and 100 year Rainfall Return Period (RRP). Total Runoff volume, peak discharge and lag time were progressively higher from 1973 to 2008 with 1989 land cover as exception where runoff parameters was its lowest. The total runoff volume, peak discharge and lag time is governed by vegetation type. When vegetation is characterized predominantly with woody perennials, runoff volume and peak time is lower. Conversely, when the presence of woody perennials is minimal, these parameters are higher. This study shows that an important way to mitigate flooding is to reduce surface runoff by maintaining vegetation predominantly composed of woody perennials.

Quantifying an Integral Ecology Framework: A Case Study of the Riverina, Australia

NASA Astrophysics Data System (ADS)

Wheeler, Sarah A.; Haensch, Juliane; Edwards, Jane; Schirmer, Jackie; Zuo, Alec

2018-02-01

Communities in Australia's Murray-Darling Basin face the challenge of trying to achieve social, economic, and environmental sustainability; but experience entrenched conflict about the best way to achieve a sustainable future, especially for small rural communities. Integral ecology is a philosophical concept that seeks to address community, economic, social, and environmental sustainability simultaneously. Its inclusive processes are designed to reduce stakeholder conflict. However, to date the application of the integral ecology concept has been largely qualitative in nature. This study developed a quantitative integral ecology framework, and applied this framework to a case study of the Riverina, in the Murray-Darling Basin. Seventy-seven community-focused initiatives were assessed, ranked, and quantified. The majority of the community-focused ranked initiatives did not exhibit all aspects of integral ecology. Initiatives typically prioritized either (1) economic and community development or (2) environmental health; rarely both together. The integral ecology framework developed here enables recommendations on future community initiatives and may provide a pathway for community leaders and other policy-makers to more readily apply integral ecology objectives. Further research refining the framework's operationalization, application and implementation to a wider-scale may enhance communities' capacity to develop and grow sustainably.

Predicting wildfire occurrence distribution with spatial point process models and its uncertainty assessment: a case study in the Lake Tahoe Basin, USA

Treesearch

Jian Yang; Peter J. Weisberg; Thomas E. Dilts; E. Louise Loudermilk; Robert M. Scheller; Alison Stanton; Carl Skinner

2015-01-01

Strategic fire and fuel management planning benefits from detailed understanding of how wildfire occurrences are distributed spatially under current climate, and from predictive models of future wildfire occurrence given climate change scenarios. In this study, we fitted historical wildfire occurrence data from 1986 to 2009 to a suite of spatial point process (SPP)...

Geologic framework for the national assessment of carbon dioxide storage resources─South Florida Basin: Chapter L in Geologic framework for the national assessment of carbon dioxide storage resources

USGS Publications Warehouse

Roberts-Ashby, Tina L.; Brennan, Sean T.; Merrill, Matthew D.; Blondes, Madalyn S.; Freeman, P.A.; Cahan, Steven M.; DeVera, Christina A.; Lohr, Celeste D.; Warwick, Peter D.; Corum, Margo D.

2015-08-26

This report presents five storage assessment units (SAUs) that have been identified as potentially suitable for geologic carbon dioxide sequestration within a 35,075-square-mile area that includes the entire onshore and State-water portions of the South Florida Basin. Platform-wide, thick successions of laterally extensive carbonates and evaporites deposited in highly cyclic depositional environments in the South Florida Basin provide several massive, porous carbonate reservoirs that are separated by evaporite seals. For each storage assessment unit identified within the basin, the areal distribution of the reservoir-seal couplet identified as suitable for geologic Carbon dioxide sequestration is presented, along with a description of the geologic characteristics that influence the potential carbon dioxide storage volume and reservoir performance. On a case-by-case basis, strategies for estimating the pore volume existing within structurally and (or) stratigraphically closed traps are also discussed. Geologic information presented in this report has been employed to calculate potential storage capacities for carbon dioxide sequestration in the storage assessment units assessed herein, although complete assessment results are not contained in this report.

Basalt depths in lunar basins using impact craters as stratigraphic probes: Evaluation of a method using orbital geochemical data

NASA Technical Reports Server (NTRS)

Andre, C. G.

1986-01-01

A rare look at the chemical composition of subsurface stratigraphy in lunar basins filled with mare basalt is possible at fresh impact craters. Mg/Al maps from orbital X-ray flourescence measurements of mare areas indicate chemical anomalies associated with materials ejected by large post-mare impacts. A method of constraining the wide-ranging estimates of mare basalt depths using the orbital MG/Al data is evaluated and the results are compared to those of investigators using different indirect methods. Chemical anomalies at impact craters within the maria indicate five locations where higher Mg/Al basalt compositions may have been excavated from beneath the surface layer. At eight other locations, low Mg/Al anomalies suggest that basin-floor material was ejected. In these two cases, the stratigraphic layers are interpreted to occur at depths less than the calculated maximum depth of excavation. In five other cases, there is no apparent chemical change between the crater and the surrounding mare surface. This suggests homogeneous basalt compositions that extend down to the depths sampled, i.e., no anorthositic material that might represent the basin floor was exposed.

Scale Issues in Modeling the Water Resources Sector in National Economic Models: A Case study of China

NASA Astrophysics Data System (ADS)

Strzepek, K. M.; Kirshen, P.; Yohe, G.

2001-05-01

The fundamental theme of this research was to investigate tradeoffs in model resolution for modeling water resources in the context of national economic development and capital investment decisions.. Based on a case study of China, the research team has developed water resource models at relatively fine scales, then investigated how they can be aggregated to regional or national scales and for use in national level planning decisions or global scale integrated assessment models of food and/or environmental change issues. The team has developed regional water supply and water demand functions.. Simplifying and aggregating the supply and demand functions will allow reduced form functions of the water sector for inclusion in large scale national economic models. Water Supply Cost functions were developed looking at both surface and groundwater supplies. Surface Water: Long time series of flows at the mouths of the 36 major river sub-basins in China are used in conjunction with different basin reservoir storage quantities to obtain storage-yield curves. These are then combined with reservoir and transmission cost data to obtain yield-cost or surface water demand curves. The methodology to obtain the long time series of flows for each basin is to fit a simple abcd water balance model to each basin. The costs of reservoir storage have been estimated by using a methodology developed in the USA that relates marginal storage costs to existing storage, slope and geological conditions. USA costs functions have then been adjusted to Chinese costs. The costs of some actual dams in China were used to "ground-truth" the methodology. Groundwater: The purpose of the groundwater work is to estimate the recharge in each basin, and the depths and quality of water of aquifers. A byproduct of the application of the abcd water balance model is the recharge. Depths and quality of aquifers are being taken from many separate reports on groundwater in different parts of China; we have been unable to find any global or regional datasets of groundwater.. Combining Surface and Groundwater Supply Functions Water Demand Curves. Water Use data is reported on political regions. Water Supply is reported and modeled on river basin regions. It is necessary to allocate water demands to river basins. To accomplish this China's 9 major river basins were divided into 36 hydroeconomic regions. The counties were then allocated to one of the 36-hydroeconomic zones. The county-level water use data was aggregated to 5 major water use sectors: 1)industry; 2)urban municipal and vegetable gardens: 3) major irrigation; 4) Energy and 5)Other agriculture (forestry, pasture; fishery). Sectoral Demand functions that include price and income elasticity were developed for the 5 sectors for each of the 9 major river basin. The supply and demand curves were aggregated at a variety of geographical scales as well as levels of economic sectoral aggregation. Implications for investment and sustainable development policies were examined for the various aggregation using partial and general equilibrium modeling of the Chinese economy. These results and policy implications for China as well as insights and recommendation for other developing countries will be presented.

Morphology and Distribution of Volcanic Vents in the Orientale Basin from Chandrayaan-1 Moon Mineralogy Mapper (M3) Data

NASA Technical Reports Server (NTRS)

Head, James; Pieters, C.; Staid, M.; Mustard, J.; Taylor, L.; McCord, T.; Isaacson, P.; Klima, R.; Petro, N.; Clark, R.;

[The origin and quality of water for human consumption: the health of the population residing in the Matanza-Riachuelo river basin area in Greater Buenos Aires].

PubMed

Monteverde, Malena; Cipponeri, Marcos; Angelaccio, Carlos; Gianuzzi, Leda

2013-04-01

The aim of this study is to analyze the origin and quality of water used for consumption in a sample of households in Matanza-Riachuelo river basin area in Greater Buenos Aires, Argentina. The results of drinking water by source indicated that 9% of water samples from the public water system, 45% of bottled water samples and 80% of well water samples were not safe for drinking due to excess content of coliforms, Escherichia coli or nitrates. Individuals living in households where well water is the main source of drinking water have a 55% higher chance of suffering a water-borne disease; in the cases of diarrheas, the probability is 87% higher and in the case of dermatitis, 160% higher. The water for human consumption in this region should be provided by centralized sources that assure control over the quality of the water.

A new eco-hydrological distributed model for the analysis of the climate change impact on water resources of Mediterranean ecosystems: the Flumendosa basin case study in Sardinia

NASA Astrophysics Data System (ADS)

Sarigu, Alessio; Cortis, Clorinda; Montaldo, Nicola

2014-05-01

In the last three decades, climate change and human activities increased desertification process in Mediterranean regions, with dramatic consequences for agriculture and water availability. For instance in the Flumendosa reservoir system in Sardinia the average annual runoff in the latter part of the 20th century was less than half the historic average rate, while the precipitation over the Flumendosa basin has decreased, but not at such a drastic rate as the discharge, suggesting a marked non-linear response of discharge to precipitation changes. With the objective of analyzing and looking for the reasons of the historical runoff decrease a new ecohydrological model is developed and tested for the main basin of the Sardinia island, the Flumendosa basin. The eco-hydrological model developed couples a distributed hydrological model and a vegetation dynamic model (VDM). The hydrological model estimates the soil water balance of each basin cell using the force-restore method and the Philips model for runoff estimate. Then it computes runoff propagation along the river network through a modified version of the Muskingum -Cunge method (Mancini et al., 2000; Montaldo et al., 2004). The VDM evaluates the changes in biomass over time from the difference between the rates of biomass production (photosynthesis) and loss (respiration and senescence), and provides LAI, which is then used by the hydrological model for evapotranspiration and rainfall interception estimates. Case study is the Flumendosa basin (Sardinia, basin area of about 1700 km2), which is characterized by a reservoir system that supplies water to the main city of Sardinia, Cagliari. Data are from 42 rain stations (1922-2008 period) over the entire basin and data of runoff are available for the same period. The model has been successfully calibrated for the 1922 - 2008 period for which rain, meteorological data and discharge data are available. We demonstrate that the hystorical strong decrease of runoff is due to a change of rainfall regime, with a decrease of rainfall during the winter months, and a little increase of rainfall during spring-summer months. Indeed, the higher Spring rainfall produced an increase of transpiration mainly, whithout any impact on runoff. Instead the decrease of rainfall in winter months produces a strong decrease of runoff. This trend impacts significantly on monthly runoff production, and, more important, on yearly runoff production, because most of the yearly runoff contribution comes from the winter months. Yearly runoff is more important in Sardinia water resources systems, because runoff is accumulated in dam reservoirs, and is the main water resources of the island. Hence, due to the change of rainfall regime in last decades we are observing a dramatic decrease of runoff, which is reaching to impact on the water availability of the Sardinian major city, Cagliari.

Estimation of Groundwater Storage Change via GRACE over a Small Watershed - A Case Study over Konya Closed Basin

NASA Astrophysics Data System (ADS)

Karasu, İ. G.; Yilmaz, K. K.; Yilmaz, M. T.

2017-12-01

Estimation of the groundwater storage change and its interannual variability is critical over Konya Closed Basin which has excessive agricultural production. The annual total precipitation falling over the region is not sufficient to compensate the agricultural irrigation needs of the region. This leds many to use groundwater as the primary water resource, which resulted in significant drop in the groundwater levels. Accordingly, monitoring of the groundwater change is critical for sustainable water resources management. Gravity Recovery and Climate Experiment (GRACE) observations and Global Land Data Assimilation System (GLDAS) have been succesfully used over many locations to monitor the change in the groundwater storages. In this study, GRACE-derived terrestrial water storage estimates and GLDAS model soil moisture, canopy water, snow water equivalent and surface runoff simulations are used to retrieve the change in the groundwater storage over Konya Closed Basin streching over 50,000 km2 area. Initial comparisons show the declining trend in GRACE and GLDAS combined groundwater storage change estimates between 2002 and 2016 are consistent with the actual groundwater level change observed at ground stations. Even though many studies recommend GRACE observations to be used over regions larger than 100,000 km2 - 200,000 km2 area, results show GRACE remote sensing and GLDAS modeled groundwater change information are skillful to monitor the large mass changes occured as a result of the excessive groundwater exploitation over Konya Closed Basin with 50,000 km2 area.

Seismic images of an extensional basin, generated at the hangingwall of a low-angle normal fault: The case of the Sansepolcro basin (Central Italy)

NASA Astrophysics Data System (ADS)

Barchi, Massimiliano R.; Ciaccio, Maria Grazia

2009-12-01

The study of syntectonic basins, generated at the hangingwall of regional low-angle detachments, can help to gain a better knowledge of these important and mechanically controversial extensional structures, constraining their kinematics and timing of activity. Seismic reflection images constrain the geometry and internal structure of the Sansepolcro Basin (the northernmost portion of the High Tiber Valley). This basin was generated at the hangingwall of the Altotiberina Fault (AtF), an E-dipping low-angle normal fault, active at least since Late Pliocene, affecting the upper crust of this portion of the Northern Apennines. The dataset analysed consists of 5 seismic reflection lines acquired in the 80s' by ENI-Agip for oil exploration and a portion of the NVR deep CROP03 profile. The interpretation of the seismic profiles provides a 3-D reconstruction of the basin's shape and of the sedimentary succession infilling the basin. This consisting of up to 1200 m of fluvial and lacustrine sediments: this succession is much thicker and possibly older than previously hypothesised. The seismic data also image the geometry at depth of the faults driving the basin onset and evolution. The western flank is bordered by a set of E-dipping normal faults, producing the uplifting and tilting of Early to Middle Pleistocene succession along the Anghiari ridge. Along the eastern flank, the sediments are markedly dragged along the SW-dipping Sansepolcro fault. Both NE- and SW-dipping faults splay out from the NE-dipping, low-angle Altotiberina fault. Both AtF and its high-angle splays are still active, as suggested by combined geological and geomorphological evidences: the historical seismicity of the area can be reasonably associated to these faults, however the available data do not constrain an unambiguous association between the single structural elements and the major earthquakes.

Understanding High Wintertime Ozone Events over an Oil and Natural Gas Production Region from Air Quality Model Perspective

NASA Astrophysics Data System (ADS)

Ahmadov, R.; McKeen, S. A.; Trainer, M.; Banta, R. M.; Brown, S. S.; Edwards, P. M.; Frost, G. J.; Gilman, J.; Helmig, D.; Johnson, B.; Karion, A.; Koss, A.; Lerner, B. M.; Oltmans, S. J.; Roberts, J. M.; Schnell, R. C.; Veres, P. R.; Warneke, C.; Williams, E. J.; Wild, R. J.; Yuan, B.; Zamora, R. J.; Petron, G.; De Gouw, J. A.; Peischl, J.

2014-12-01

The huge increase in production of oil and natural gas has been associated with high wintertime ozone events over some parts of the western US. The Uinta Basin, UT, where oil and natural gas production is abundant experienced high ozone concentrations in winters of recent years, when cold stagnant weather conditions were prevalent. It has been very challenging for conventional air quality models to accurately simulate such wintertime ozone pollution cases. Here, a regional air quality model study was successfully conducted for the Uinta Basin by using the WRF-Chem model. For this purpose a new emission dataset for the region's oil/gas sector was built based on atmospheric in-situ measurements made during 2012 and 2013 field campaigns in the Uinta Basin. The WRF-Chem model demonstrates that the major factors driving high ozone in the Uinta Basin in winter are shallow boundary layers with light winds, high emissions of volatile organic compounds (VOC) compared to nitrogen oxides emissions from the oil and natural gas industry, enhancement of photolysis rates and reduction of O3 dry deposition due to snow cover. We present multiple sensitivity simulations to quantify the contribution of various factors driving high ozone over the Uinta Basin. The emission perturbation simulations show that the photochemical conditions in the Basin during winter of 2013 were VOC sensitive, which suggests that targeting VOC emissions would be most beneficial for regulatory purposes. Shortcomings of the emissions within the most recent US EPA (NEI-2011, version 1) inventory are also discussed.

Water reuse in the Apatlaco River Basin (México): a feasibility study.

PubMed

Moeller-Chávez, G; Seguí-Amórtegui, L; Alfranca-Burriel, O; Escalante-Estrada, V; Pozo-Román, F; Rivas-Hernández, A

2004-01-01

The aim of this work is to determine the technical and economic feasibility of implementing different reclamation and reuse projects that improve the quality of the Apatlaco river basin located in the central part of Mexico. A special methodology based on a decision support system was developed. This methodology allows to decide if it is convenient or not to finance a reclamation or reuse project for the most common water uses in the basin. This methodology is based on the net present value criteria (NPV) of the effective cash flow during the useful life of the project. The results obtained reveal a technical and economical feasibility for industrial reuse in Jiutepec and for agricultural reuse in Zacatepec and Emiliano Zapata. On the other hand, sanitation projects are not feasible in all cases analyzed. Therefore, Mexican Regulation (Ley Federal de Derechos en Materia de Agua) as currently implemented, does not promote and support this kind of projects.

Seismic shaking in the North China Basin expected from ruptures of a possible seismic gap

NASA Astrophysics Data System (ADS)

Duan, Benchun; Liu, Dunyu; Yin, An

2017-05-01

A 160 km long seismic gap, which has not been ruptured over 8000 years, was identified recently in North China. In this study, we use a dynamic source model and a newly available high-resolution 3-D velocity structure to simulate long-period ground motion (up to 0.5 Hz) from possibly worst case rupture scenarios of the seismic gap. We find that the characteristics of the earthquake source and the local geologic structure play a critical role in controlling the amplitude and distribution of the simulated strong ground shaking. Rupture directivity and slip asperities can result in large-amplitude (i.e., >1 m/s) ground shaking near the fault, whereas long-duration shaking may occur within sedimentary basins. In particular, a deep and closed Quaternary basin between Beijing and Tianjin can lead to ground shaking of several tens of cm/s for more than 1 min. These results may provide a sound basis for seismic mitigation in one of the most populated regions in the world.

Option contracts for allocating water in inter-basin transfers: the case of the Tagus-Segura Transfer in Spain

NASA Astrophysics Data System (ADS)

Rey, Dolores; Garrido, Alberto; Calatraba, Javier

2014-05-01

Users in the Mediterranean region face significant water supply risks. Water markets mechanisms can provide flexibility to water systems run in tight situations. The largest water infrastructure in the Iberian Peninsula connects the Segura and Tagus Basins. Stakeholders and politicians in the Tagus Basin have asked that water transfers between the two basins be eventually phased out. The need to increase the statutory minimum environmental flow in the middle Tagus and to meet new urban demands is going to result in a redefinition of the Transfer's management rules, leading to a reduction in the transferable volumes. To minimise the consequences of such restrictions to irrigators in the Segura Basin who depend on the transferred volumes, we propose the establishment of water option contracts between both basins that represents an institutional innovation with respect to previous inter-basin spot market experiences. Based on the draft of the new Tagus Basin Plan, we propose both a modification of the Transfer's management rule and an innovative inter-basin option contract. The main goal of the paper is to define this contract and evaluate it with respect to non-market scenarios. We also assess the resulting impact on environmental flows in the Tagus River and water availability for users in the Segura Basin, together with the economic impacts of such contract on both basins. Our results show that the proposed option contract would reduce the impact of a change in the transfer's management rule, and reduce the supply risks of the recipient area. Keywords: environmental flow, inter-basin transfer, option contracts, Tagus-Segura, water markets, water supply reliability.

Forecasting risk along a river basin using a probabilistic and deterministic model for environmental risk assessment of effluents through ecotoxicological evaluation and GIS.

PubMed

Gutiérrez, Simón; Fernandez, Carlos; Barata, Carlos; Tarazona, José Vicente

2009-12-20

This work presents a computer model for Risk Assessment of Basins by Ecotoxicological Evaluation (RABETOX). The model is based on whole effluent toxicity testing and water flows along a specific river basin. It is capable of estimating the risk along a river segment using deterministic and probabilistic approaches. The Henares River Basin was selected as a case study to demonstrate the importance of seasonal hydrological variations in Mediterranean regions. As model inputs, two different ecotoxicity tests (the miniaturized Daphnia magna acute test and the D.magna feeding test) were performed on grab samples from 5 waste water treatment plant effluents. Also used as model inputs were flow data from the past 25 years, water velocity measurements and precise distance measurements using Geographical Information Systems (GIS). The model was implemented into a spreadsheet and the results were interpreted and represented using GIS in order to facilitate risk communication. To better understand the bioassays results, the effluents were screened through SPME-GC/MS analysis. The deterministic model, performed each month during one calendar year, showed a significant seasonal variation of risk while revealing that September represents the worst-case scenario with values up to 950 Risk Units. This classifies the entire area of study for the month of September as "sublethal significant risk for standard species". The probabilistic approach using Monte Carlo analysis was performed on 7 different forecast points distributed along the Henares River. A 0% probability of finding "low risk" was found at all forecast points with a more than 50% probability of finding "potential risk for sensitive species". The values obtained through both the deterministic and probabilistic approximations reveal the presence of certain substances, which might be causing sublethal effects in the aquatic species present in the Henares River.

The SOLUTIONS project: challenges and responses for present and future emerging pollutants in land and water resources management.

PubMed

Brack, Werner; Altenburger, Rolf; Schüürmann, Gerrit; Krauss, Martin; López Herráez, David; van Gils, Jos; Slobodnik, Jaroslav; Munthe, John; Gawlik, Bernd Manfred; van Wezel, Annemarie; Schriks, Merijn; Hollender, Juliane; Tollefsen, Knut Erik; Mekenyan, Ovanes; Dimitrov, Saby; Bunke, Dirk; Cousins, Ian; Posthuma, Leo; van den Brink, Paul J; López de Alda, Miren; Barceló, Damià; Faust, Michael; Kortenkamp, Andreas; Scrimshaw, Mark; Ignatova, Svetlana; Engelen, Guy; Massmann, Gudrun; Lemkine, Gregory; Teodorovic, Ivana; Walz, Karl-Heinz; Dulio, Valeria; Jonker, Michiel T O; Jäger, Felix; Chipman, Kevin; Falciani, Francesco; Liska, Igor; Rooke, David; Zhang, Xiaowei; Hollert, Henner; Vrana, Branislav; Hilscherova, Klara; Kramer, Kees; Neumann, Steffen; Hammerbacher, Ruth; Backhaus, Thomas; Mack, Juliane; Segner, Helmut; Escher, Beate; de Aragão Umbuzeiro, Gisela

2015-01-15

SOLUTIONS (2013 to 2018) is a European Union Seventh Framework Programme Project (EU-FP7). The project aims to deliver a conceptual framework to support the evidence-based development of environmental policies with regard to water quality. SOLUTIONS will develop the tools for the identification, prioritisation and assessment of those water contaminants that may pose a risk to ecosystems and human health. To this end, a new generation of chemical and effect-based monitoring tools is developed and integrated with a full set of exposure, effect and risk assessment models. SOLUTIONS attempts to address legacy, present and future contamination by integrating monitoring and modelling based approaches with scenarios on future developments in society, economy and technology and thus in contamination. The project follows a solutions-oriented approach by addressing major problems of water and chemicals management and by assessing abatement options. SOLUTIONS takes advantage of the access to the infrastructure necessary to investigate the large basins of the Danube and Rhine as well as relevant Mediterranean basins as case studies, and puts major efforts on stakeholder dialogue and support. Particularly, the EU Water Framework Directive (WFD) Common Implementation Strategy (CIS) working groups, International River Commissions, and water works associations are directly supported with consistent guidance for the early detection, identification, prioritisation, and abatement of chemicals in the water cycle. SOLUTIONS will give a specific emphasis on concepts and tools for the impact and risk assessment of complex mixtures of emerging pollutants, their metabolites and transformation products. Analytical and effect-based screening tools will be applied together with ecological assessment tools for the identification of toxicants and their impacts. The SOLUTIONS approach is expected to provide transparent and evidence-based candidates or River Basin Specific Pollutants in the case study basins and to assist future review of priority pollutants under the WFD as well as potential abatement options. Copyright © 2014 Elsevier B.V. All rights reserved.

Historical upscaling of the socio-hydrological cycle: Three cases from the Mediterranean Spain

NASA Astrophysics Data System (ADS)

Macian-Sorribes, Hector; Pulido-Velazquez, Manuel; Sanchis-Ibor, Carles

2015-04-01

Understanding the co-evolution between hydrological and socio-economic systems is vital to assess how anthropogenic and natural systems will evolve and interact in the future. Examining past socio-hydrological changes is therefore important to produce knowledge able to develop socio-hydrological models for predicting the future hydrology and society evolution patterns. As noticeable climate changes leading to higher water stress are expected in the Mediterranean Europe, socio-hydrological processes are likely to suffer considerable modifications in the XXI century, driving to potential conflicts as water demand increases while water resources fall. The goal of this contribution is to identify the hydro-social processes that have caused water conflicts, and how they have been solved in the Mediterranean Spain. The method is based in the analysis of historical documents, available since the Middle Ages. Once historical water conflicts (always well-documented) were located, a socio-hydrological "causal loop" is formulated, determining what caused that conflict, what factors or chain of factors were involved, and how it was addressed. Repeating that process for all the reported water conflicts allow us to gain insight into their driving forces, the socio-hydrological relationships linked to those, and the successful (and unsuccessful) strategies employed to address them. Three cases were selected from the Mediterranean Spain: the Mijares, the Turia and the Jucar river basins. All of them share similar documental sources (the Royal Archives, courts' archives, municipal archives and farmers' archives), similar climate and similar socio-economic backgrounds. Moreover, all of them are predicted to suffer similar climate change impacts. Irrigation is their major water demand. In these three rivers, during the last millennia, successive waterscapes have been constructed by different societies, in a prolonged process of institutional and environmental up-scaling, from the local level to the basin level, based on collaborative actions through multistakeholder partnerships and agreements. Irrigation development has played a major role in the evolutionary trend of the hydro-social cycle in the three basins, determining water demands and uses, and boosting institutional building. Following the main historical institutional milestones and examining the historical changes in water uses, remarkable differences can be found among the three cases, enhancing the high sensitivity of the hydrological processes with respect to socio-economic factors. Therefore, comparing them is adequate to find out those high-sensitive factors and the way they provoke the differences between the basins. The casual loop created a basin closure - basin reopening cycle. Basin closures were associated to increasing demands by population growth, irrigation and immigration, causing drought vulnerability. Basin reopenings corresponded to the building of regulation facilities (reservoirs, canals), the availability of new water sources (groundwater, regenerated water), or a change in the management strategies (conjunctive use). During basin closure, users fought during droughts but united to prevent new users' access to water. During reopenings, water use quickly increased, leading to basin closures. User conflicts were solved by user agreement in water sharing or by law requirement, establishing a new management policy. New-user conflicts were solved when the basin reopened again and those potential users gained access to water.

Evolution of canals system linking the Vistula, Dnieper and Neman basins

NASA Astrophysics Data System (ADS)

Brykala, Dariusz; Badziai, Vitali

2014-05-01

The aim of this study is to reconstruct landscape changes in the Polesie Region - one of the largest European swampy areas (Belarus), as a result of the creation and operation of a network of canals. From the 16th century efforts were undertaken to connect the Polish areas located in the drainage basins of the Black Sea and Baltic Sea with canals. Already in 1631 the Polish Sejm (parliament) approved the project to build a canal linking the River Berezina (Dnieper basin) with the River Neris (Neman basin). However, the complicated political and economic situation of the country did not allow doing this. Only in the second half of the 18th c. hetman Ogiński financed the construction of a canal linking the Dnieper and Neman basins. The canal connecting the River Szczara (Neman basin) with the River Jasiołda (Pripyat basin) was named after its creator - the Ogiński Canal. At the same time the construction of the Królewski (Royal) Canal linking the River Muchavets (Vistula basin) and the River Pina (Pripyat basin) was under way. The construction of the canal was completed in 1783. The winding channels of the Pina and Muchavets were straightened, and the numerous canals feeding the waterway system drained vast area of marshes and wetlands of the Polesia Region. The last element that connects the catchments of the Vistula and Neman is the Augustów Canal built in the years 1825-1839 (linking the catchments of the Biebrza and Neman). Numerous changes in political boundaries in the watershed area between the Black Sea and the Baltic Sea drainage basins caused the destruction of the hydraulic structures. All the analysed canals were completely destroyed during the two world wars. In the last 200 years the amount and type of locks and weirs has changed. For example, there were no weirs on the Royal Canal in the late 18th c., in the middle of the 19th c. there were 22 such structures, while now that number has gone down to 10. All canals were created for economic reasons, i.e. of the need for floating of timber and food. Currently, in most cases they are tourist attractions only. Only the Królewski Canal, known as the Dnieper-Bug Canal, plays a very important transportation role in the economy of Belarus. These studies are a contribution to the Virtual Institute of Integrated Climate and Landscape Evolution Analysis (ICLEA) and intergovernmental agreement on scientific cooperation between Poland and Belarus in years 2011-2013: No. 13.

Impact of Climate Change on Irrigation and Hydropower Potential: A Case of Upper Blue Nile Basin

NASA Astrophysics Data System (ADS)

Abdella, E. J.; Gosain, A. K.; Khosa, R.

2017-12-01

Due to the growing pressure in water resource and climate change there is great uncertainty in the availability of water for existing as well as proposed irrigation and hydropower projects in the Upper Blue Nile basin (longitude 34oE and 39oE and latitude 7oN and 12oN). This study quantitatively assessed the impact of climate change on the hydrological regime of the basin which intern affect water availability for different use including hydropower and irrigation. Ensemble of four bias corrected regional climate models (RCM) of CORDEX Africa domain and two scenarios (RCP 4.5 and RCP 8.5) were used to determine climate projections for future (2021-2050) period. The outputs from the climate models used to drive the calibrated Soil and Water Assessment Tool (SWAT) hydrologic model to simulate future runoff. The simulated discharge were used as input to a Water Evaluation and Planning (WEAP) water allocation model to determine the implication in hydropower and irrigation potential of the basin. The WEAP model was setup to simulate three scenarios which includes Current, Medium-term (by 2025) and Long-term (by 2050) Development scenario. The projected mean annual temperature of the basin are warmer than the baseline (1982 - 2005) average in the range of 1 to 1.4oC. Projected mean annual precipitation varies across the basin in the range of - 3% to 7%, much of the expected increase is in the highland region of the basin. The water use simulation indicate that the current annual average irrigation water demand in the basin is 1.29Bm3y-1 with 100% coverage. By 2025 and 2050, with the development of new schemes and changing climate, water demand for irrigation is estimated to increase by 2.5 Bm3y-1 and 3.4 Bm3y-1 with 99 % and 96% coverage respectively. Simulation for domestic water demand coverage for all scenarios shows that there will be 100% coverage for the two major cities in the basin. The hydropower generation simulation indicate that 98% of hydroelectricity potential could be produced if all planed dams are constructed. The results in this study demonstrate the general idea of future water availability for different purpose in the basin, but uncertainties still exist in the projected future climate and simulated runoff. Optimal operation of existing and proposed reservoirs is also crucial in the context of climate change.

Urbanization dramatically altered the water balances of a paddy field dominated basin in southern China

Treesearch

L. Hao; G. Sun; Y. Liu; J. Wan; M. Qin; H. Qian; C. Liu; R. John; P. Fan; J. Chen

2015-01-01

Rice paddy fields provide important ecosystem services (e.g., food production, water retention, carbon sequestration) to a large population globally. However, these benefits are declining as a result of rapid environmental and socioeconomic transformations characterized by population growth, urbanization, and climate change in many Asian countries. This case study...

Prior knowledge-based approach for associating contaminants with biological effects: A case study in the St. Croix river basin, MN, WI, USA.

EPA Science Inventory

Evaluating the potential human health and/or ecological risks associated with exposures to complex chemical mixtures in the ambient environment is one of the central challenges of chemical safety assessment and environmental protection. There is a need for approaches that can he...

Impacts of domestic and and agricultural rainwater harvesting system on watershed hydrology: A case study of Albemarle-Pamlico Watershed basins (NC, VA, USA)

EPA Science Inventory

Rainwater harvesting (RWH) is increasingly relevant in the context of growing population and its demands on water quantity. Here, we present a method to better understand the hydrologic impacts of urban domestic and agricultural rainwater harvesting and apply the approach to thre...

Evaluating MODIS snow products for modelling snowmelt runoff: case study of the Rio Grande headwaters

USDA-ARS?s Scientific Manuscript database

Snow-covered area (SCA) is a key variable in the Snowmelt-Runoff Model (SRM). Landsat Thematic Mapper (TM) or Operational Land Imager (OLI) provide remotely sensed data at an appropriate spatial resolution for mapping SCA in small headwater basins, but the temporal resolution of the data is low and ...

ANALYTIC ELEMENT MODELING FOR SOURCE WATER ASSESSMENTS OF PUBLIC WATER SUPPLY WELLS: CASE STUDIES IN GLACIAL OUTWASH AND BASIN-AND-RANGE

EPA Science Inventory

Over the last 10 years the EPA has invested in analytic elements as a computational method used in public domain software supporting capture zone delineation for source water assessments and wellhead protection. The current release is called WhAEM2000 (wellhead analytic element ...

Application of the ELOHA framework to regulated rivers in the upper Tennessee River Basin: A case study

Treesearch

Ryan A. McManamay; Donald J. Orth; Charles A. Dolloff; David C. Mathews

2013-01-01

In order for habitat restoration in regulated rivers to be effective at large scales, broadly applicable frameworks are needed that provide measurable objectives and contexts for management. The Ecological Limits of Hydrologic Alteration (ELOHA) framework was created as a template to assess hydrologic alterations, develop relationships between altered streamflow and...

DETECTING CHANGES IN RIPARIAN HABITAT CONDITIONS BASED ON PATTERNS OF GREENNESS CHANGE: A CASE STUDY FROM THE UPPER SAN PEDRO RIVER BASIN, USA

EPA Science Inventory

Healthy riparian ecosystems in arid and semi-arid regions exhibit shifting patterns of vegetation in response to periodic flooding. Their conditions also depend upon the amount of grazing and other human uses. Taking advantage of these system properties, we developed and tested a...

Linking Changes in Management and Riparian Physical Functionality to Water Quality and Aquatic Habitat: A Case Study of Maggie Creek, NV

EPA Science Inventory

The total maximum daily load (TMDL) process is ineffective and inappropriate for improving stream water quality in the rural areas of the northern Great Basin, and likely in many areas throughout the country. Important pollutants (e.g., sediment and nutrients) come from the stre...

Ground Water Recharge Estimation Using Water Table Fluctuation Method And By GIS Applications

NASA Astrophysics Data System (ADS)

Vajja, V.; Bekkam, V.; Nune, R.; M. v. S, R.

2007-05-01

Quite often it has become a debating point that how much recharge is occurring to the groundwater table through rainfall on one hand and through recharge structures such as percolation ponds and checkdams on the other. In the present investigations Musi basin of Andhra Pradesh, India is selected for study during the period 2005-06. Pre-monsoon and Post-monsoon groundwater levels are collected through out the Musi basin at 89 locations covering an area11, 291.69 km2. Geology of the study area and rainfall data during the study period has been collected. The contour maps of rainfall and the change in groundwater level between Pre-monsoon and Post- monsoon have been prepared. First the change in groundwater storage is estimated for each successive strips of areas enclosed between two contours of groundwater level fluctuations. In this calculation Specific yield (Sy) values are adopted based on the local Geology. Areas between the contours are estimated through Arc GIS software package. All such storages are added to compute the total storage for the entire basin. In order to find out the percent of rainfall converted into groundwater storage as well as to find out the ground water recharge due to storageponds, a contour map of rainfall for the study area is prepared and areas between successive contours have been calculated. Based on the Geology map, Infiltration values are adopted for each successive strip of the contour area. Then the amount of water infiltrated into the ground is calculated by adjusting the infiltration values for each strip, so that the total infiltrated water for the entire basin is matched with change in Ground water storage, which is 1314.37 MCM for the upper Musi basin while it is 2827.29 MCM for entire Musi basin. With this procedure on an average 29.68 and 30.66 percent of Rainfall is converted into Groundwater recharge for Upper Musi and for entire Musi basin respectively. In the total recharge, the contribution of rainfall directly to Groundwater recharge is 8.53 and 8.81 percent and the remaining 21.15 and 21.85 percent is due to groundwater recharge from water conservation structures such as check dams, contour bunds, tanks, etc. for Upper Musi and for entire Musi basin respectively. The difference is attributable to the canal recharge in the case of Lower Musi. Therefore the Upper Musi values may be taken as a percent of Rainfall that is converted into Groundwater recharge.

Case study on rehabilitation of a polluted urban water body in Yangtze River Basin.

PubMed

Wu, Juan; Cheng, Shuiping; Li, Zhu; Guo, Weijie; Zhong, Fei; Yin, Daqiang

2013-10-01

In the past three decades, the fast development of economy and urbanization has caused increasingly severe pollutions of urban water bodies in China. Consequently, eutrophication and deterioration of aquatic ecosystem, which is especially significant for aquatic vegetation, inevitably became a pervasive problem across the Yangtze River Basin. To rehabilitate the degraded urban water bodies, vegetation replanting is an important issue to improve water quality and to rehabilitate ecosystem. As a case study, a representative polluted urban river, Nanfeihe River, in Hefei City, Anhui Province, was chosen to be a rehabilitation target. In October 2009 and May 2010, 13 species of indigenous and prevalent macrophytes, including seven species emergent, one species floating leaved, and five species submersed macrophytes, were planted along the bank slopes and in the river. Through 1.5 years' replanting practice, the water quality and biodiversity of the river had been improved. The concentrations of total nitrogen (TN), total phosphorus (TP), and ammonia nitrogen (NH4 (+)-N) declined by 46.0, 39.5, and 60.4 %, respectively. The species of macrophytes increased from 14 to 60, and the biodiversity of phytoplankton rose significantly in the river (p<0.05). The biomasses of zooplankton and benthos were also improved after the vegetation replanting. The study confirmed that vegetation replanting could alleviate the increasing water pollution and rehabilitate the degraded aquatic ecosystem. The case study would be an example for polluted urban waters restoration in the middle-downstream area of Yangtze River Base.

Analyse sismo-stratigraphique du bassin d'Abda (Maroc occidental), exemple de structures inverses pendant le rifting atlantiqueSeismo-stratigraphic analysis of the Abda Basin (West Morocco): a case of reverse structures during the Atlantic rifting

NASA Astrophysics Data System (ADS)

Echarfaoui, Hassan; Hafid, Mohamed; Salem, Abdallah Aı̈t; Abderrahmane, Aı̈t Fora

The review of the seismic reflection and well data from the coastal Abda Basin (western Morocco) shows that its Triassic and Jurassic sequences were deposited in a submeridean sag basin, whose eastern margin is characterised by progressive truncations and pinching out of these sequences against a prominent Palaeozoic high. The uplift of this latter is interpreted as a response to an Upper Triassic-Middle Jurassic local compressional event that controlled Triassic-Jurassic sedimentation within the Abda Basin. The present day 'West Meseta Flexure' is a surface expression of this uplift. To cite this article: H. Echarfaoui et al., C. R. Geoscience 334 (2002) 371-377.

A parametric study of the value of hydrological information for irrigation and hydropower management of the Feather River

NASA Technical Reports Server (NTRS)

Wetzler, E.; Sand, F.; Stevenson, P.; Putnam, M.

1975-01-01

A case study analysis is presented of the relationships between improvements in the accuracy, frequency, and timeliness of information used in making hydrological forecasts and economic benefits in the areas of hydropower and irrigation. The area chosen for the case study is the Oroville Dam and Reservoir. Emphasis is placed on the use of timely and accurate mapping of the aerial extent of snow in the basin by earth resources survey systems such as LANDSAT. The subject of benefits resulting from improved runoff forecasts is treated in a generalized way without specifying the source of the improvements.

Pre-existing normal faults have limited control on the rift geometry of the northern North Sea

NASA Astrophysics Data System (ADS)

Claringbould, Johan S.; Bell, Rebecca E.; Jackson, Christopher A.-L.; Gawthorpe, Robert L.; Odinsen, Tore

2017-10-01

Many rifts develop in response to multiphase extension with numerical and physical models suggesting that reactivation of first-phase normal faults and rift-related variations in bulk crustal rheology control the evolution and final geometry of subsequent rifts. However, many natural multiphase rifts are deeply buried and thus poorly exposed in the field and poorly imaged in seismic reflection data, making it difficult to test these models. Here we integrate recent 3D seismic reflection and borehole data across the entire East Shetland Basin, northern North Sea, to constrain the long-term, regional development of this multiphase rift. We document the following key stages of basin development: (i) pre-Triassic to earliest Triassic development of multiple sub-basins controlled by widely distributed, NNW- to NE-trending, east- and west-dipping faults; (ii) Triassic activity on a single major, NE-trending, west-dipping fault located near the basins western margin, and formation of a large half-graben; and (iii) Jurassic development of a large, E-dipping, N- to NE-trending half-graben near the eastern margin of the basin, which was associated with rift narrowing and strain focusing in the Viking Graben. In contrast to previous studies, which argue for two discrete periods of rifting during the Permian-Triassic and Late Jurassic-Early Cretaceous, we find that rifting in the East Shetland Basin was protracted from pre-Triassic to Cretaceous. We find that, during the Jurassic, most pre-Jurassic normal faults were buried and in some cases cross-cut by newly formed faults, with only a few being reactivated. Previously developed faults thus had only a limited control on the evolution and geometry of the later rift. We instead argue that strain migration and rift narrowing was linked to the evolving thermal state of the lithosphere, an interpretation supporting the predictions of lithosphere-scale numerical models. Our study indicates that additional regional studies of natural rifts are required to test and refine the predictions of physical and numerical models, more specifically, our study suggests models not explicitly recognising or including thermal or rheological effects might over emphasise the role of discrete pre-existing rift structures such as normal faults.

Regime Behavior in Paleo-Reconstructed Streamflow: Attributions to Atmospheric Dynamics, Synoptic Circulation and Large-Scale Climate Teleconnection Patterns

NASA Astrophysics Data System (ADS)

Ravindranath, A.; Devineni, N.

2017-12-01

Studies have shown that streamflow behavior and dynamics have a significant link with climate and climate variability. Patterns of persistent regime behavior from extended streamflow records in many watersheds justify investigating large-scale climate mechanisms as potential drivers of hydrologic regime behavior and streamflow variability. Understanding such streamflow-climate relationships is crucial to forecasting/simulation systems and the planning and management of water resources. In this study, hidden Markov models are used with reconstructed streamflow to detect regime-like behaviors - the hidden states - and state transition phenomena. Individual extreme events and their spatial variability across the basin are then verified with the identified states. Wavelet analysis is performed to examine the signals over time in the streamflow records. Joint analyses of the climatic data in the 20th century and the identified states are undertaken to better understand the hydroclimatic connections within the basin as well as important teleconnections that influence water supply. Compositing techniques are used to identify atmospheric circulation patterns associated with identified states of streamflow. The grouping of such synoptic patterns and their frequency are then examined. Sliding time-window correlation analysis and cross-wavelet spectral analysis are performed to establish the synchronicity of basin flows to the identified synoptic and teleconnection patterns. The Missouri River Basin (MRB) is examined in this study, both as a means of better understanding the synoptic climate controls in this important watershed and as a case study for the techniques developed here. Initial wavelet analyses of reconstructed streamflow at major gauges in the MRB show multidecadal cycles in regime behavior.

Optimal allocation of bulk water supplies to competing use sectors based on economic criterion - An application to the Chao Phraya River Basin, Thailand

NASA Astrophysics Data System (ADS)

Divakar, L.; Babel, M. S.; Perret, S. R.; Gupta, A. Das

2011-04-01

SummaryThe study develops a model for optimal bulk allocations of limited available water based on an economic criterion to competing use sectors such as agriculture, domestic, industry and hydropower. The model comprises a reservoir operation module (ROM) and a water allocation module (WAM). ROM determines the amount of water available for allocation, which is used as an input to WAM with an objective function to maximize the net economic benefits of bulk allocations to different use sectors. The total net benefit functions for agriculture and hydropower sectors and the marginal net benefit from domestic and industrial sectors are established and are categorically taken as fixed in the present study. The developed model is applied to the Chao Phraya basin in Thailand. The case study results indicate that the WAM can improve net economic returns compared to the current water allocation practices.

Public awareness of landslide hazards: the Barranco de Tirajana, Gran Canaria, Spain

NASA Astrophysics Data System (ADS)

Carmen Solana, M.; Kilburn, Christopher R. J.

2003-08-01

When engineering methods are not cost-effective in reducing the danger from landslides, it is crucial that vulnerable communities are aware of the hazards they face and know how to respond in an emergency. Such awareness can best be maintained by a public-information programme designed around a population's existing perception of landslides. As a case study to gauge the awareness of landslide hazards, a survey has been conducted among vulnerable communities in the Barranco de Tirajana (BdT) Basin on Gran Canaria, one of the most active zones of slope movement in the Canary Islands. Results from a formal questionnaire, together with anecdotal evidence, suggest that the communities are generally aware that landslides occur in the Basin and can be dangerous, but that they rarely consider slope movements as a potential hazard to themselves. Consequently, the communities are also uncertain about the most effective response during an emergency. Another result is that there is little pressure on local authorities either to prepare contingency plans in case of major destruction by landslides, or to enforce stricter building codes to reduce the persistent damage caused by creep. Having highlighted the weaknesses in hazard perception, the results of the survey have been used to design an awareness programme for the Basin. They may also be used as a basis for similar initiatives elsewhere.

[Epidemiological trends for malaria in the cities of the upper Paraguay River basin, Mato Grosso do Sul, Brazil 1990-1996].

PubMed

Matsumoto, W K; Vicente, M G; Silva, M A; de Castro, L L

1998-01-01

Through the Regional Office of the Brazilian National Health Foundation in the State of Mato Grosso do Sul, we obtained numerical data on malaria for the upper Paraguay basin (UPB): 159 cases in 1990, 126 in 1991, 135 in 1992, 61 in 1993, 143 in 1994, 41 in 1995, and 20 in 1996, the majority of which were imported cases. There were no autochthonous cases in 1990, and since 1991 the rates of over 15% dropped to around 1.60%. Imported cases, corresponding to 0. 63% in 1990, increased in 1991 and 1992 to some 1.50%, and to 3.28% in 1993. Induced cases were recorded only in 1991 and 1992 (less than 1%). Most cases were between 16 and 45 years of age. There was a predominance of Plasmodium vivax in the thick blood smears. Although autochthonous cases of malaria are not the majority, the disease is still an important public health problem in the UPB in the presence of the Anopheles (N.) darlingi vector and human migration into the region.

Mapping potential zones for groundwater recharge and its evaluation in arid environments using a GIS approach: Case study of North Gafsa Basin (Central Tunisia)

NASA Astrophysics Data System (ADS)

Mokadem, Naziha; Boughariou, Emna; Mudarra, Matías; Ben Brahim, Fatma; Andreo, Bartolome; Hamed, Younes; Bouri, Salem

2018-05-01

With the progressive evolution of industrial sector, agricultural, urbanization, population and drinking water supply, the water demand continuously increases which necessitates the planning of groundwater recharge particularly in arid and semi-arid regions. This paper gives a comprehensive review of various recharges studies in the North Gafsa basin (South Tunisia). This latter is characterized by a natural groundwater recharge that is deeply affected by the lack of precipitations. The aim of this study is to determine the recharge potential zones and to quantify (or estimate) the rainfall recharge of the shallow aquifers. The mapping of the potential recharge zones was established in North Gafsa basin, using geological and hydrological parameters such as slope, lithology, topography and stream network. Indeed, GIS provide tools to reclassify these input layers to produce the final map of groundwater potential zones of the study area. The final output map reveals two distinct zones representing moderate and low groundwater potential recharge. Recharge estimations were based on the four methods: (1) Chloride Method, (2) ERAS Method, (3) DGRE coefficient and (4) Fersi equations. Therefore, the overall results of the different methods demonstrate that the use of the DGRE method applying on the potential zones is more validated.

Walled Sedimentary Basins of China: Perpetrators or Victims of Plateau Growth?

NASA Astrophysics Data System (ADS)

Carroll, A. R.; Graham, S. A.; Smith, M. E.

2004-12-01

Western China and adjacent areas of central Asia are characterized by low relief, internally drained sedimentary basins that are divided by actively uplifting mountain ranges. The margins of these basins often show evidence for extensive contractional deformation, yet their interiors are surprisingly stable. Basins such as the Tarim and Junggar also exhibit long and apparently continuous histories of closed drainage in the same approximate location (over 250 my in the case of Junggar). In contrast to traditional foreland basins, these basins are not uniquely associated with a specific thrust belt, nor do they show evidence for underlying decollements. We therefore propose the new term "walled basin", in recognition of the essential role of peripheral orogenic walls in creating and maintaining closed drainage and impounding sediments. Walled basins in Asia currently are restricted to areas that receive less than 40 cm/yr precipitation, suggesting that aridity plays a role in preventing fluvial breach of the basin walls (cf., Sobel et al., 2003). Entrapment of sediment within the closed Qaidam basin in the northeast Tibetan plateau has been implicated as a potential mechanism of plateau growth, based on the observations that the basin retains mass within the orogen and creates level topography. However, we propose that the Qaidam instead represents a walled basin that has been elevated due to underplating of the plateau, and is fated to eventual destruction as deformation continues. Several lines of reasoning support this conclusion. First, DEM analysis shows that modern drainage divides for the Qaidam and other walled basins never rise more than 1-2 km above the basin floors, limiting the amount of possible topgraphic infill. Second, the Tarim and Junggar basins presently remain well below 2000 m and probably have never been higher, despite receiving large influxes of detritus from adjacent ranges. Third, the Qaidam basin, like the Tarim and Junggar basins, has an older history of nonmarine fill that dates back at least to the Jurassic, and therefore its existence predates the Himalayan orogeny. Fourth, mid-Tertiary and older fill of the Qaidam basin has already been deformed, indicating an ongoing history of structural shortening. Finally, closed geomorphic basins within the southern Tibetan plateau are all much smaller than the Qaidam. This suggests that brittle deformation associated with progressive south to north underplating has disrupted preexisting sedimentary basins that were originally more prominent than they are now.

Derivation of debris flow critical rainfall thresholds from land stability modeling

NASA Astrophysics Data System (ADS)

Papa, M. N.; Medina, V.; Bateman, A.; Ciervo, F.

2012-04-01

The aim of the work is to develop a system capable of providing debris flow warnings in areas where historical events data are not available as well as in the case of changing environments and climate. For these reasons, critical rainfall threshold curves are derived from mathematical and numerical simulations rather than the classical derivation from empirical rainfall data. The operational use of distributed model, based on the stability analysis for each grid cell of the basin, is not feasible in the case of warnings due to the long running time required for this kind of model as well as the lack of detailed information on the spatial distribution of the properties of the material in many practical cases. Moreover, with the aim of giving debris flow warnings, it is not necessary to know the distribution of instable elements along the basin but only if a debris flow may affect the vulnerable areas in the valley. The capability of a debris flow of reaching the downstream areas depends on many factors linked with the topography, the solid concentration, the rheological properties of the debris mixture and the flow discharge as well as the occurrence of liquefaction of the sliding mass. In relation to a specific basin, many of these factors may be considered as not time dependent. The most rainfall dependent factors are flow discharge and correlated total debris volume. In the present study, the total volume that is instable, and therefore available for the flow, is considered as the governing factor from which it is possible to assess whether a debris flow will affect the downstream areas or not. The possible triggering debris flow is simulated, in a generic element of the basin, by an infinite slope stability analysis. The groundwater pressure is calculated by the superposition of the effect of an "antecedent" rainfall and an "event" rainfall. The groundwater pressure response to antecedent rainfall is used as the initial condition for the time-dependent computation of the groundwater pressure response to the event rainfall. Antecedent rainfall response is estimated in the hypotheses of low intensity and long duration, thus assuming steady state conditions and slope parallel groundwater flux. The short term response to rainfall is assessed in the hypothesis of vertical infiltration. The simulations are performed in a virtual basin, representative of the one studied, taking into account the uncertainties linked with the definition of the characteristics of the soil. The approach presented is based on the simulation of a large number of cases covering the entire range of the governing input dynamic variables. For any possible combination of rainfall intensity, duration and antecedent rain, the total debris volume, available for the flow, is estimated. The resulting database is elaborated in order to obtain rainfall threshold curves. When operating in real time, if the observed and forecasted rainfall exceeds a given threshold, the corresponding probability of debris flow occurrence may be estimated.

Detecting inter-aquifer leakage in areas with limited data using hydraulics and multiple environmental tracers, including 4He, 36Cl/Cl, 14C and 87Sr/86Sr

NASA Astrophysics Data System (ADS)

Priestley, Stacey C.; Wohling, Daniel L.; Keppel, Mark N.; Post, Vincent E. A.; Love, Andrew J.; Shand, Paul; Tyroller, Lina; Kipfer, Rolf

2017-11-01

The investigation of regionally extensive groundwater systems in remote areas is hindered by a shortage of data due to a sparse observation network, which limits our understanding of the hydrogeological processes in arid regions. The study used a multidisciplinary approach to determine hydraulic connectivity between the Great Artesian Basin (GAB) and the underlying Arckaringa Basin in the desert region of Central Australia. In order to manage the impacts of groundwater abstraction from the Arckaringa Basin, it is vital to understand its connectivity with the GAB (upper aquifer), as the latter supports local pastoral stations and groundwater-dependent springs with unique endemic flora and fauna. The study is based on the collation of available geological information, a detailed analysis of hydraulic data, and data on environmental tracers. Enhanced inter-aquifer leakage in the centre of the study area was identified, as well as recharge to the GAB from ephemeral rivers and waterholes. Throughout the rest of the study area, inter-aquifer leakage is likely controlled by diffuse inter-aquifer leakage, but the coarse spatial resolution means that the presence of additional enhanced inter-aquifer leakage sites cannot be excluded. This study makes the case that a multi-tracer approach along with groundwater hydraulics and geology provides a tool-set to investigate enhanced inter-aquifer leakage even in a groundwater basin with a paucity of data. A particular problem encountered in this study was the ambiguous interpretation of different age tracers, which is attributed to diffusive transport across flow paths caused by low recharge rates.

Creeping Environmental Problems and Sustainable Development in the Aral Sea Basin

NASA Astrophysics Data System (ADS)

Glantz, Michael

1999-05-01

Environmental degradation in the Aral Sea basin in Central Asia has been a touchstone for increasing public awareness of environmental issues. The Aral crisis has been touted as a "quiet Chernobyl" and as one of the worst human-made environmental catastrophes of the twentieth century. This multidisciplinary book is the first to comprehensively describe the slow onset of low grade but incremental changes (i.e., creeping environmental change) that affected the region and its peoples. Through a set of case studies, it describes how the region's decision-makers allowed these changes to grow into an environmental and societal nightmare. It outlines many lessons to be learned for other areas undergoing detrimental creeping environmental change, and provides an important example of how to approach such disasters for students and researchers of environmental studies, global change, political science and history.

Genetic research of fractures in carbonate reservoir: a case study of NT carbonate reservoir in the pre-Caspian basin

NASA Astrophysics Data System (ADS)

Fan, Zifei; Wang, Shuqin; Li, Jianxin; Zhao, Wenqi; Sun, Meng; Li, Weiqiang; Li, Changhai

2018-02-01

The degree of development and characteristics of fractures are key factors for the appraisal of carbonate reservoirs. In this paper, core data and well logging data from the NT oilfield in the Pre-Caspian Basin are used to study the formation mechanism and distribution characteristics of different genetic fractures, and analyze their influence on reservoir properties. Fractures in carbonate reservoirs can be divided into three categories according to their formation mechanism; these are tectonic fracture, dissolved fracture, and diagenetic fracture,which is further divided into interlayer fracture and stylolite. Fractures of different formation mechanism influence fluid seepage in different degree, tectonic fractures possessing strong connecting ability to pores, and dissolved fractures also improving reservoir properties effectively, however, diagenetic fractures contributing relatively little to fluid seepage.

Preliminary Geological Map of the Ac-H-14 Yalode Quadrangle of Ceres: An Integrated Mapping Study Using Dawn Spacecraft Data

NASA Astrophysics Data System (ADS)

Crown, D. A.; Yingst, R. A.; Mest, S. C.; Platz, T.; Williams, D. A.; Buczkowski, D.; Schenk, P.; Scully, J. E. C.; Jaumann, R.; Roatsch, T.; Preusker, F.; Nathues, A.; Hoffmann, M.; Schäfer, M.; Marchi, S.; De Sanctis, M. C.; Russell, C.; Raymond, C. A.

2015-12-01

We are conducting a geologic mapping investigation of the Ac-H-14 Yalode Quadrangle (21-66°S, 270-360°E) of Ceres to examine its surface geology and geologic history. At the time of this writing, geologic mapping has been performed on Dawn Framing Camera (FC) mosaics from the late Approach phase (up to 1.3 km/px) and Survey orbit (415 m/px), including clear filter and color images and digital terrain models derived from stereo images. In Fall 2015 images from the High Altitude Mapping Orbit (140 m/px) will be used to refine the mapping, followed by the Low Altitude Mapping Orbit (35 m/px) starting in December 2015. The Yalode Quadrangle is dominated by the ~300-km diameter impact basin Yalode and includes rugged and smooth terrains to the east. Yalode basin has a variably preserved rim, which is continuous and sharply defined to the north/northwest and is irregular or degraded elsewhere, and may have an interior ring structure. The basin floor includes hummocky and smooth areas (some bounded by scarps), crater chains, and a lineated zone. High-resolution images will be used to search for volcanic features on the basin floor and in association with basin structures. Yalode basin and its floor deposits appear to have been strongly affected by the Urvara impact to the west. Impact craters in Yalode Quadrangle display a range of preservation states. Degraded features, including Yalode basin and numerous smaller craters, exhibit subdued rims, lack discrete ejecta deposits, and have infilled interiors. More pristine features (including the large unnamed basin in the SE corner of the quadrangle and craters on Yalode basin floor) have well-defined, quasi-circular forms with prominent rims and in some cases discernible ejecta. Some of these craters have bowl-shaped interiors and others contain hills or mounds on their floors. Support of the Dawn Instrument, Operations, and Science Teams is acknowledged. This work is supported by grants from NASA, MPG, and DLR.

An investigation into the bedrock depth in the Eskisehir Quaternary Basin (Turkey) using the microtremor method

NASA Astrophysics Data System (ADS)

Tün, M.; Pekkan, E.; Özel, O.; Guney, Y.

2016-10-01

Amplification can occur in a graben as a result of strong earthquake-induced ground motion. Thus, in seismic hazard and seismic site response studies, it is of the utmost importance to determine the geometry of the bedrock depth. The main objectives of this study were to determine the bedrock depth and map the depth-to-bedrock ratio for use in land use planning in regard to the mitigation of earthquake hazards in the Eskişehir Basin. The fundamental resonance frequencies (fr) of 318 investigation sites in the Eskişehir Basin were determined through case studies, and the 2-D S-wave velocity structure down to the bedrock depth was explored. Single-station microtremor data were collected from the 318 sites, as well as microtremor array data from nine sites, seismic reflection data from six sites, deep-drilling log data from three sites and shallow drilling log data from ten sites in the Eskişehir Graben. The fundamental resonance frequencies of the Eskişehir Basin sites were obtained from the microtremor data using the horizontal-to vertical (H/V) spectral ratio (HVSR) method. The phase velocities of the Rayleigh waves were estimated from the microtremor data using the spatial autocorrelation (SPAC) method. The fundamental resonance frequency range at the deepest point of the Eskişehir Basin was found to be 0.23-0.35 Hz. Based on the microtremor array measurements and the 2-D S-wave velocity profiles obtained using the SPAC method, a bedrock level with an average velocity of 1300 m s-1 was accepted as the bedrock depth limit in the region. The log data from a deep borehole and a seismic reflection cross-section of the basement rocks of the Eskişehir Basin were obtained and permitted a comparison of bedrock levels. Tests carried out using a multichannel walk-away technique permitted a seismic reflection cross-section to be obtained up to a depth of 1500-2000 m using an explosive energy source. The relationship between the fundamental resonance frequency in the Eskişehir Basin and the results of deep drilling, shallow drilling, shear wave velocity measurement and sedimentary cover depth measurement obtained from the seismic reflection section was expressed in the form of a nonlinear regression equation. An empirical relationship between fr, the thickness of sediments and the bedrock depth is suggested for use in future microzonation studies of sites in the region. The results revealed a maximum basin depth of 1000 m, located in the northeast of the Eskişehir Basin, and the SPAC and HVSR results indicated that within the study area the basin is characterized by a thin local sedimentary cover with low shear wave velocity overlying stiff materials, resulting in a sharp velocity contrast. The thicknesses of the old Quaternary and Tertiary fluvial sediments within the basin serve as the primary data sources in seismic hazard and seismic site response studies, and these results add to the body of available seismic hazard data contributing to a seismic microzonation of the Eskişehir Graben in advance of the severe earthquakes expected in the Anatolian Region.

The Caspar Creek watersheds: a case study of cumulative effects in a small coastal basin in northern California

Treesearch

R. R. Ziemer; P. H. Cafferata

1991-01-01

Abstract - Since 1962, the 483-ha North Fork and 424-ha South Fork of Caspar Creek in northwestern California have been used to evaluate the hydrologic impacts of road building and harvesting second-growth redwood/Douglas-fir forests. Three tributaries are serving as untreated controls. In 1985, the study was modified to evaluate the cumulative watershed effects of...

Effectiveness of fuel treatments for mitigating wildfire risk and sequestering forest carbon: a case study in the Lake Tahoe Basin

Treesearch

Louise Loudermilk; Alison Stanton; Robert M. Scheller; Thomas E. Dilts; Peter J. Weisberg; Carl Skinner; Jian Yang

2014-01-01

Fuel-reduction treatments are used extensively to reduce wildfire risk and restore forest diversity and function. In the near future, increasing regulation of carbon (C) emissions may force forest managers to balance the use of fuel treatments for reducing wildfire risk against an alternative goal of C sequestration. The objective of this study was to evaluate how long...

Functioning of the Primary Aquifer Relating to the Maider Basin, Morocco: Case of the Ordovician aquifer.

NASA Astrophysics Data System (ADS)

Ben-said, E.; Boukdir, A.; Mahboub, A.; Younsi, A.; Zitouni, A.; Alili, L.; Ikhmerdi, H.

2018-05-01

The basin of Maider is limited northly by the vast ensemble Oriental Saghro-Ougnate, from the east by the Tafilalet plain, from the west by the oriental Jbel Bani, finally from the south and south-east by the Cretaceous Hamada of Kern-Kem. During last decades, groundwater in the basin of Maider, is confronting degradation in both cases: Quantitative and qualitative, as a result of the drought, the overexploitation and the salinization. The aim of this action research is to understand the current state of water resources in the area of stady. At the end of this work, we can get the following conclusions: the general flow of the ordovician aquifer is always directed from the north to the south-east of the basin by following the principal axes of the wadis:Taghbalt, Hssiya and Fezzou. The recharge of the aquifer is primarily done, either by the underground flow, or by the surface runoff of torrential waters from the upstream of Jbel Saghro. The piezometric anomaly noticed at the level of Ait Saàdane, explained by overexploitation linked to the needs of irrigation water. The physicochemical approach for the Maider basin identifies two essential factors of the salinisation of groundwater: the dissolution of the aquifer which is rich in minerals with high temperature on the one hand, and the decrease of the piezometric surface due to the overexploitation and drought on the other hand.

Effect of DEM resolution on rainfall-triggered landslide modeling within a triangulated network-based model. A case study in the Luquillo Forest, Puerto Rico

NASA Astrophysics Data System (ADS)

Arnone, E.; Dialynas, Y. G.; Noto, L. V.; Bras, R. L.

2013-12-01

Catchment slope distribution is one of the topographic characteristics that significantly control rainfall-triggered landslide modeling, in both direct and indirect ways. Slope directly determines the soil volume associated with instability. Indirectly slope also affects the subsurface lateral redistribution of soil moisture across the basin, which in turn determines the water pore pressure conditions that impact slope stability. In this study, we investigate the influence of DEM resolution on slope stability and the slope stability analysis by using a distributed eco-hydrological and landslide model, the tRIBS-VEGGIE (Triangulated Irregular Network (TIN)-based Real-time Integrated Basin Simulator - VEGetation Generator for Interactive Evolution). The model implements a triangulated irregular network to describe the topography, and it is capable of evaluating vegetation dynamics and predicting shallow landslides triggered by rainfall. The impact of DEM resolution on the landslide prediction was studied using five TINs derived from five grid DEMs at different resolutions, i.e. 10, 20, 30, 50 and 70 m respectively. The analysis was carried out on the Mameyes Basin, located in the Luquillo Experimental Forest in Puerto Rico, where previous landslide analyses have been carried out. Results showed that the use of the irregular mesh reduced the loss of accuracy in the derived slope distribution when coarser resolutions were used. The impact of the different resolutions on soil moisture patterns was important only when the lateral redistribution was considerable, depending on hydrological properties and rainfall forcing. In some cases, the use of different DEM resolutions did not significantly affect tRIBS-VEGGIE landslide output, in terms of landslide locations, and values of slope and soil moisture at failure.

Regional scale flood modeling using NEXRAD rainfall, GIS, and HEC-HMS/RAS: a case study for the San Antonio River Basin Summer 2002 storm event.

PubMed

Knebl, M R; Yang, Z-L; Hutchison, K; Maidment, D R

2005-06-01

This paper develops a framework for regional scale flood modeling that integrates NEXRAD Level III rainfall, GIS, and a hydrological model (HEC-HMS/RAS). The San Antonio River Basin (about 4000 square miles, 10,000 km2) in Central Texas, USA, is the domain of the study because it is a region subject to frequent occurrences of severe flash flooding. A major flood in the summer of 2002 is chosen as a case to examine the modeling framework. The model consists of a rainfall-runoff model (HEC-HMS) that converts precipitation excess to overland flow and channel runoff, as well as a hydraulic model (HEC-RAS) that models unsteady state flow through the river channel network based on the HEC-HMS-derived hydrographs. HEC-HMS is run on a 4 x 4 km grid in the domain, a resolution consistent with the resolution of NEXRAD rainfall taken from the local river authority. Watershed parameters are calibrated manually to produce a good simulation of discharge at 12 subbasins. With the calibrated discharge, HEC-RAS is capable of producing floodplain polygons that are comparable to the satellite imagery. The modeling framework presented in this study incorporates a portion of the recently developed GIS tool named Map to Map that has been created on a local scale and extends it to a regional scale. The results of this research will benefit future modeling efforts by providing a tool for hydrological forecasts of flooding on a regional scale. While designed for the San Antonio River Basin, this regional scale model may be used as a prototype for model applications in other areas of the country.

Building the ensemble flood prediction system by using numerical weather prediction data: Case study in Kinu river basin, Japan

NASA Astrophysics Data System (ADS)

Ishitsuka, Y.; Yoshimura, K.

2016-12-01

Floods have a potential to be a major source of economic or human damage caused by natural disasters. Flood prediction systems were developed all over the world and to treat the uncertainty of the prediction ensemble simulation is commonly adopted. In this study, ensemble flood prediction system using global scale land surface and hydrodynamic model was developed. The system requests surface atmospheric forcing and Land Surface Model, MATSIRO, calculates runoff. Those generated runoff is inputted to hydrodynamic model CaMa-Flood to calculate discharge and flood inundation. CaMa-Flood can simulate flood area and its fraction by introducing floodplain connected to river channel. Forecast leadtime was set 39hours according to forcing data. For the case study, the flood occurred at Kinu river basin, Japan in 2015 was hindcasted. In a 1761 km² Kinu river basin, 3-days accumulated average rainfall was 384mm and over 4000 people was left in the inundated area. Available ensemble numerical weather prediction data at that time was inputted to the system in a resolution of 0.05 degrees and 1hour time step. As a result, the system predicted the flood occurrence by 45% and 84% at 23 and 11 hours before the water level exceeded the evacuation threshold, respectively. Those prediction lead time may provide the chance for early preparation for the floods such as levee reinforcement or evacuation. Adding to the discharge, flood area predictability was also analyzed. Although those models were applied for Japan region, this system can be applied easily to other region or even global scale. The areal flood prediction in meso to global scale would be useful for detecting hot zones or vulnerable areas over each region.

Case study of small harbor excitation under storm and tsunami conditions

NASA Astrophysics Data System (ADS)

Synolakis, Costas; Maravelakis, Nikos; Kalligeris, Nikos; Skanavis, Vassilios; Kanoglu, Utku; Yalciner, Ahmet; Lynett, Pat

2016-04-01

Simultaneous nearshore and interior-to-ports wave and current measurements for small ports are not common, and few, if any, benchmarking cases at sufficient resolution exist to help validate numerical model of intermediate waves, or even long waves. The wave conditions inside the old Venetian harbor of Chania, Greece and offshore were measured and studied from 2012 to 2015. The construction of this harbor began in the 14th century, and since then, its layout has been modified to adapt to different social and to economic conditions. It is divided into a western and an eastern basin. The eastern basin is used by recreational vessels and fishing boats throughout the year. The western basin has an exposed entrance to the north, and it is essentially functional half of the year, because of the severe overtopping and flooding that occur during the northern winter storms. Our work is motivated by the necessity to protect the monument from severe winter storm conditions and allow safe mooring and all other recreational activities that take place in the exposed western basin. Two earlier studies had proposed the construction of a low crested breakwater near the harbor entrance. The first design has been partially constructed, while the second never materialized. The main disadvantage of both studies was the lack of any wave field measurements. At the same time, second order or complimentary phenomena such as harbor resonance had not been considered. To address the lack of field data, the offshore wave climate has been monitored since October 2012 using an AWAC 600kHz instrument, deployed at 23m depth. The response of the western and eastern basins of the harbor was measured with a TWR-2050 (deployed at 5.5m depth) and an RBRDuet T.D./wave (deployed at 2m depth) pressure gauges respectively. Significant wave heights ranging up to 5.8 m with significant periods of up to 10 sec were measured. The harbor pressure gauges are now being re-deployed in other locations to collect enough information to infer the resonant modes of the basins excited during storm conditions. The deployment position of the pressure gauges is based on numerical modeling results. We have employed the fully nonlinear Boussinesq module of COULWAVE using a high resolution (2m cell size) relief model and an idealized TMA directional wave spectrum. The wave field and low frequency energy distribution in the basin are captured by both numerical modeling and field measurements. The field measurements agree well with the numerical modeling analysis, providing insight as to the causes of severe disturbance and useful information that should be considered for an effective solution to the protection of the harbor. Our measurements appear the first ever nearshore measurements of waves and currents for a 2+ year period duration in Greece. The work is also being used for validation tsunami inundation models for civil defense applications in Crete. * This work was supported by the project ASTARTE, Grant no 603839 7th FP (ENV.213.6.4.3) to the Technical University of Crete and to the Middle East Technical University.

Modulation of frontogenetic plankton production along a meandering jet by zonal wind forcing: An application to the Alboran Sea

NASA Astrophysics Data System (ADS)

Oguz, Temel; Mourre, Baptiste; Tintoré, Joaquin

2017-08-01

We present a coupled physical-biological modeling study to elucidate the changes in ageostrophic frontal dynamics and the frontogenetic plankton production characteristics of a meandering jet under the impacts of successive westerly/easterly wind events combined with seasonal variations in the upstream transport and buoyancy flux characteristics of the jet, using a case study for the Alboran Sea (Western Mediterranean). Their nonlinear coupling is shown to result in different forms of physical and biological characteristics of the background jet structure that follows a meandering path around two anticyclonic gyres in the western and eastern basins and a cyclonic eddy in between. The westerly, downfront wind events broaden the jet, and result in stronger cross-frontal density contrast and intensify ageostrophic cross-frontal secondary circulation. Thus, they improve the frontogenetic plankton production with respect to the no-wind case. They also support higher production along the northern coast in response to wind-induced coastal upwelling and spreading of resulting nutrient-rich, productive water by mesoscale stirring. These features weaken gradually as the jet transport reduces. In contrast, stronger and longer-lasting easterlies during the reduced jet transport phase weaken the currents and frontal density structure, change the circular Western Alboran Gyre to an elongated form, and shift the main axis of the jet towards the southern basin. Then, frontogenesis fails to contribute to phytoplankton production that becomes limited to the eddy pumping within cyclones. Apart from the frontogenetic production, eddy pumping, mesoscale stirring, and diapycnal mixing of nutrients support intermittent and localized phytoplankton patches over the basin.

Assessing landscape hydroperiods across the Mekong Basin using multi-scale remote sensing to understand water-energy-food tradeoffs

NASA Astrophysics Data System (ADS)

Torbick, N.; Salas, W.; Qi, J.; Huang, X.

2017-12-01

In the Lower Mekong River Basin (LMRB), population growth and transitioning economies, shifting climate, and intense pressures for resources are driving tradeoffs among the water-enegery-food (WEF) nexus. Rice production and irrigation, wetlands habitat, and damn constructions are intertwinned across the region. There are 11 major hydropower dams on the main stem of the Lower Mekong River and many smaller dams in the basin. At the same time increased pressure for food production has amplified cropping intensity and irrigation infrastructure projects. These human acitivies are impacting inundation patterns and phenology of wetland and lake ecosystems. We are mapping rice, wetlands, and lake inundation dynamics using multi-scale satellite remote sensing. New opportunities exist for moderate scale, near-daily mapping of rice, wetland, shrimp, and lake hydroperiod with multi-source imaging and BigData computational approaches on the NAS cloud. Primarily we rely on Sentinel-1 IW and PALSAR-2 ScanSAR to map inundation dynamics at 10m resolution including under canopy conditions using double bounce properties. As part of this effort we are assessing different damn impacts at case studies in Thailand, Cambodia, Laos, and Vietnam with high resolution commercial imagery, social surveys, and socioeconomic models. These dams are currently regulated individually without coordination. As a result, their operation has outsized impacts on lake and wetland ecologies, negatively affecting the associated ecosystem services that local communities have relied on. All new products are shared openly with the science community. Case study illustrations will be presented.

Classification of gravity-flow deposits and their significance for unconventional petroleum exploration, with a case study from the Triassic Yanchang Formation (southern Ordos Basin, China)

NASA Astrophysics Data System (ADS)

Fan, Aiping; Yang, Renchao; (Tom) van Loon, A. J.; Yin, Wei; Han, Zuozhen; Zavala, Carlos

2018-08-01

The ongoing exploration for shale oil and gas has focused sedimentological research on the transport and deposition mechanisms of fine-grained sediments, and more specifically on fine-grained mass-flow deposits. It appears, however, that no easily applicable classification scheme for gravity-flow deposits exists, and that such classifications almost exclusively deal with sandy and coarser sediments. Since the lack of a good classification system for fine-grained gravity flow deposits hampers scientific communication and understanding, we propose a classification scheme on the basis of the mud content in combination with the presumed transport mechanism. This results in twelve types of gravity-flow deposits. In order to show the practical applicability of this classification system, we apply it to the Triassic lacustrine Yanchang Formation in the southern Ordos Basin (China), which contains numerous slumps, debris-flows deposits, turbidites and hyperpycnites. The slumps and debrites occur mostly close to a delta front, and the turbidites and hyperpycnites extend over large areas from the delta slopes into the basin plain. The case study shows that (1) mud cannot only be transported but also deposited under active hydrodynamic conditions; (2) fine-grained gravity-flow constitute a significant part of the lacustrine mudstones and shales; (3) muddy gravity flows are important for the transport and deposition of clastic particles, clay minerals and organic matter, and thus are important mechanisms involved in the generation of hydrocarbons, also largely determining the reservoir capability for unconventional petroleum.

Adequacy of TRMM satellite rainfall data in driving the SWAT modeling of Tiaoxi catchment (Taihu lake basin, China)

NASA Astrophysics Data System (ADS)

Li, Dan; Christakos, George; Ding, Xinxin; Wu, Jiaping

2018-01-01

Spatial rainfall data is an essential input to Distributed Hydrological Models (DHM), and a significant contributor to hydrological model uncertainty. Model uncertainty is higher when rain gauges are sparse, as is often the case in practice. Currently, satellite-based precipitation products increasingly provide an alternative means to ground-based rainfall estimates, in which case a rigorous product assessment is required before implementation. Accordingly, the twofold objective of this work paper was the real-world assessment of both (a) the Tropical Rainfall Measuring Mission (TRMM) rainfall product using gauge data, and (b) the TRMM product's role in forcing data for hydrologic simulations in the area of the Tiaoxi catchment (Taihu lake basin, China). The TRMM rainfall products used in this study are the Version-7 real-time 3B42RT and the post-real-time 3B42. It was found that the TRMM rainfall data showed a superior performance at the monthly and annual scales, fitting well with surface observation-based frequency rainfall distributions. The Nash-Sutcliffe Coefficient of Efficiency (NSCE) and the relative bias ratio (BIAS) were used to evaluate hydrologic model performance. The satisfactory performance of the monthly runoff simulations in the Tiaoxi study supports the view that the implementation of real-time 3B42RT allows considerable room for improvement. At the same time, post-real-time 3B42 can be a valuable tool of hydrologic modeling, water balance analysis, and basin water resource management, especially in developing countries or at remote locations in which rainfall gauges are scarce.

The Water Footprint as an indicator of environmental sustainability in water use at the river basin level.

PubMed

Pellicer-Martínez, Francisco; Martínez-Paz, José Miguel

2016-11-15

One of the main challenges in water management is to determine how the current water use can condition its availability to future generations and hence its sustainability. This study proposes the use of the Water Footprint (WF) indicator to assess the environmental sustainability in water resources management at the river basin level. The current study presents the methodology developed and applies it to a case study. The WF is a relatively new indicator that measures the total volume of freshwater that is used as a production factor. Its application is ever growing in the evaluation of water use in production processes. The calculation of the WF involves water resources (blue), precipitation stored in the soil (green) and pollution (grey). It provides a comprehensive assessment of the environmental sustainability of water use in a river basin. The methodology is based upon the simulation of the anthropised water cycle, which is conducted by combining a hydrological model and a decision support system. The methodology allows the assessment of the environmental sustainability of water management at different levels, and/or ex-ante analysis of how the decisions made in water planning process affect sustainability. The sustainability study was carried out in the Segura River Basin (SRB) in South-eastern Spain. The SRB is among the most complex basins in Europe, given its special peculiarities: competition for the use, overexploitation of aquifers, pollution, alternative sources, among others. The results indicate that blue water use is not sustainable due to the generalised overexploitation of aquifers. They also reveal that surface water pollution, which is not sustainable, is mainly caused by phosphate concentrations. The assessment of future scenarios reveals that these problems will worsen if no additional measures are implemented, and therefore the water management in the SRB is environmentally unsustainable in both the short- and medium-term. Copyright © 2016 Elsevier B.V. All rights reserved.

Development of a relative risk model for evaluating ecological risk of water environment in the Haihe River Basin estuary area.

PubMed

Chen, Qiuying; Liu, Jingling; Ho, Kin Chung; Yang, Zhifeng

2012-03-15

Ecological risk assessment for water environment is significant to water resource management of basin. Effective environmental management and systems restoration such as the Haihe River Basin require holistic understanding of the relative importance of various stressor-related impacts throughout the basin. As an effective technical tool for evaluating the ecological risk, relative risk model (RRM) was applied in regional scale successfully. In this study, the risk transfer from upstream of basin was considered and the RRM was developed through introducing the source-stressor-habitat exposure filter (SSH), the endpoint-habitat exposure filter (EH) and the stressor-endpoint effect filter (SE) to reflect the meaning of exposure and effect more explicit. Water environment which includes water quality, water quantity and aquatic ecosystems was selected as the assessment endpoints. We created a conceptual model which depicting potential and effect pathways from source to stressor to habitat to endpoint. The Haihe River Basin estuary (HRBE) was selected as the model case. The results showed that there were two low risk regions, one medium risk region and two high risk regions in the HRBE. The results also indicated that urbanization was the biggest source, the second was shipping and the third was industry, their risk scores are 5.65, 4.71 and 3.68 respectively. Furthermore, habitat destruction was the largest stressor with the risk scores (2.66), the second was oxygen consuming organic pollutants (1.75) and the third was pathogens (1.75). So these three stressors were the main influencing factors of the ecological pressure in the study area. For habitats, open waters (9.59) and intertidal mudflat were enduring the bigger pressure and should be taken considerable attention. Ecological service values damaged (30.54) and biodiversity decreased were facing the biggest risk pressure. Copyright © 2011 Elsevier B.V. All rights reserved.

Exploring Sedimentary Basins with High Frequency Receiver Function: the Dublin Basin Case Study

NASA Astrophysics Data System (ADS)

Licciardi, A.; Piana Agostinetti, N.

2015-12-01

The Receiver Function (RF) method is a widely applied seismological tool for the imaging of crustal and lithospheric structures beneath a single seismic station with one to tens kilometers of vertical resolution. However, detailed information about the upper crust (0-10 km depth) can also be retrieved by increasing the frequency content of the analyzed RF data-set (with a vertical resolution lower than 0.5km). This information includes depth of velocity contrasts, S-wave velocities within layers, as well as presence and location of seismic anisotropy or dipping interfaces (e.g., induced by faulting) at depth. These observables provides valuable constraints on the structural settings and properties of sedimentary basins both for scientific and industrial applications. To test the RF capabilities for this high resolution application, six broadband seismic stations have been deployed across the southwestern margin of the Dublin Basin (DB), Ireland, whose geothermal potential has been investigated in the last few years. With an inter-station distance of about 1km, this closely spaced array has been designed to provide a clear picture of the structural transition between the margin and the inner portion of the basin. In this study, a Bayesian approach is used to retrieve the posterior probability distributions of S-wave velocity at depth beneath each seismic station. A multi-frequency RF data-set is analyzed and RF and curves of apparent velocity are jointly inverted to better constrain absolute velocity variations. A pseudo 2D section is built to observe the lateral changes in elastic properties across the margin of the basin with a focus in the shallow portion of the crust. Moreover, by means of the harmonic decomposition technique, the azimuthal variations in the RF data-set are isolated and interpreted in terms of anisotropy and dipping interfaces associated with the major fault system in the area. These results are compared with the available information from previous seismic active surveys in the area, including boreholes data.

Natural and human forcing in recent geomorphic change; case studies in the Rio de la Plata basin.

PubMed

Bonachea, Jaime; Bruschi, Viola M; Hurtado, Martín A; Forte, Luis M; da Silva, Mario; Etcheverry, Ricardo; Cavallotto, José L; Dantas, Marcilene F; Pejon, Osni J; Zuquette, Lázaro V; Bezerra, Maria Angélica de O; Remondo, Juan; Rivas, Victoria; Gómez-Arozamena, José; Fernández, Gema; Cendrero, Antonio

2010-06-01

An analysis of geomorphic system's response to change in human and natural drivers in some areas within the Río de la Plata basin is presented. The aim is to determine whether an acceleration of geomorphic processes has taken place in recent years and, if so, to what extent it is due to natural (climate) or human (land-use) drivers. Study areas of different size, socio-economic and geomorphic conditions have been selected: the Río de la Plata estuary and three sub-basins within its watershed. Sediment cores were extracted and dated ((210)Pb) to determine sedimentation rates since the end of the 19th century. Rates were compared with time series on rainfall as well as human drivers such as population, GDP, livestock load, crop area, energy consumption or cement consumption, all of them related to human capacity to disturb land surface. Data on river discharge were also gathered. Results obtained indicate that sedimentation rates during the last century have remained essentially constant in a remote Andean basin, whereas they show important increases in the other two, particularly one located by the São Paulo metropolitan area. Rates in the estuary are somewhere in between. It appears that there is an intensification of denudation/sedimentation processes within the basin. Rainfall remained stable or varied very slightly during the period analysed and does not seem to explain increases of sedimentation rates observed. Human drivers, particularly those more directly related to capacity to disturb land surface (GDP, energy or cement consumption) show variations that suggest human forcing is a more likely explanation for the observed change in geomorphic processes. It appears that a marked increase in denudation, of a "technological" nature, is taking place in this basin and leading to an acceleration of sediment supply. This is coherent with similar increases observed in other regions. Copyright (c) 2010 Elsevier B.V. All rights reserved.

Sierra Nevada snowpack and runoff prediction integrating basin-wide wireless-sensor network data

NASA Astrophysics Data System (ADS)

Yoon, Y.; Conklin, M. H.; Bales, R. C.; Zhang, Z.; Zheng, Z.; Glaser, S. D.

2016-12-01

We focus on characterizing snowpack and estimating runoff from snowmelt in high elevation area (>2100 m) in Sierra Nevada for daily (for use in, e.g. flood and hydropower forecasting), seasonal (supply prediction), and decadal (long-term planning) time scale. Here, basin-wide wireless-sensor network data (ARHO, http://glaser.berkeley.edu/wsn/) is integrated into the USGS Precipitation-Runoff Modeling System (PRMS), and a case study of the American River basin is presented. In the American River basin, over 140 wireless sensors have been planted in 14 sites considering elevation gradient, slope, aspect, and vegetation density, which provides spatially distributed snow depth, temperature, solar radiation, and soil moisture from 2013. 800 m daily gridded dataset (PRISM) is used as the climate input for the PRMS. Model parameters are obtained from various sources (e.g., NLCD 2011, SSURGO, and NED) with a regionalization method and GIS analysis. We use a stepwise framework for a model calibration to improve model performance and localities of estimates. For this, entire basin is divided into 12 subbasins that include full natural flow measurements. The study period is between 1982 and 2014, which contains three major storm events and recent severe drought. Simulated snow depth and snow water equivalent (SWE) are initially compared with the water year 2014 ARHO observations. The overall results show reasonable agreements having the Nash-Sutcliffe efficiency coefficient (NS) of 0.7, ranged from 0.3 to 0.86. However, the results indicate a tendency to underestimate the SWE in a high elevation area compared with ARHO observations, which is caused by the underestimated PRISM precipitation data. Precipitation at gauge-sparse regions (e.g., high elevation area), in general, cannot be well represented in gridded datasets. Streamflow estimates of the basin outlet have NS of 0.93, percent bias of 7.8%, and normalized root mean square error of 3.6% for the monthly time scale.

Origin and migration of hydrocarbon gases and carbon dioxide, Bekes Basin, southeastern Hungary

USGS Publications Warehouse

Clayton, J.L.; Spencer, C.W.; Koncz, I.; Szalay, A.

1990-01-01

The Bekes Basin is a sub-basin within the Pannonian Basin, containing about 7000 m of post-Cretaceous sedimentary rocks. Natural gases are produced from reservoirs (Precambrian to Tertiary in age) located on structural highs around the margins of the basin. Gas composition and stable carbon isotopic data indicate that most of the flammable gases were derived from humic kerogen contained in source rocks located in the deep basin. The depth of gas generation and vertical migration distances were estimated using quantitative source rock maturity-carbon isotope relationships for methane compared to known Neogene source rock maturity-depth relationships in the basin. These calculations indicate that as much as 3500 m of vertical migration has occured in some cases. Isotopically heavy (> - 7 > 0) CO2 is the predominant species present in some shallow reservoirs located on basin-margin structural highs and has probably been derived via long-distance vertical and lateral migration from thermal decompositon of carbonate minerals in Mesozoic and older rocks in the deepest parts of the basin. A few shallow reservoirs (< 2000m) contain isotopically light (-50 to -60%0) methane with only minor amounts of C2+ homologs (< 3% v/v). This methane is probably mostly microbial in origin. Above-normal pressures, occuring at depths greater than 1800 m, are believed to be the principal driving force for lateral and vertical gas migration. These pressures are caused in part by active hydrocarbon generation, undercompaction, and thermal decomposition of carbonates. 

Hydrological modelling of the Mara River Basin, Kenya: Dealing with uncertain data quality and calibrating using river stage

NASA Astrophysics Data System (ADS)

Hulsman, P.; Bogaard, T.; Savenije, H. H. G.

2016-12-01

In hydrology and water resources management, discharge is the main time series for model calibration. Rating curves are needed to derive discharge from continuously measured water levels. However, assuring their quality is demanding due to dynamic changes and problems in accurately deriving discharge at high flows. This is valid everywhere, but even more in African socio-economic context. To cope with these uncertainties, this study proposes to use water levels instead of discharge data for calibration. Also uncertainties in rainfall measurements, especially the spatial heterogeneity needs to be considered. In this study, the semi-distributed rainfall runoff model FLEX-Topo was applied to the Mara River Basin. In this model seven sub-basins were distinguished and four hydrological response units with each a unique model structure based on the expected dominant flow processes. Parameter and process constrains were applied to exclude unrealistic results. To calibrate the model, the water levels were back-calculated from modelled discharges, using cross-section data and the Strickler formula calibrating parameter `k•s1/2', and compared to measured water levels. The model simulated the water depths well for the entire basin and the Nyangores sub-basin in the north. However, the calibrated and observed rating curves differed significantly at the basin outlet, probably due to uncertainties in the measured discharge, but at Nyangores they were almost identical. To assess the effect of rainfall uncertainties on the hydrological model, the representative rainfall in each sub-basin was estimated with three different methods: 1) single station, 2) average precipitation, 3) areal sub-division using Thiessen polygons. All three methods gave on average similar results, but method 1 resulted in more flashy responses, method 2 dampened the water levels due to averaging the rainfall and method 3 was a combination of both. In conclusion, in the case of unreliable rating curves, water level data can be used instead and a new rating curve can be calibrated. The effect of rainfall uncertainties on the hydrological model was insignificant.

Harmonic analyses of stream temperatures in the Upper Colorado River Basin

USGS Publications Warehouse

Steele, T.D.

1985-01-01

Harmonic analyses were made for available daily water-temperature records for 36 measurement sites on major streams in the Upper Colorado River Basin and for 14 measurement sites on streams in the Piceance structural basin. Generally (88 percent of the station years analyzed), more than 80 percent of the annual variability of temperatures of streams in the Upper Colorado River Basin was explained by the simple-harmonic function. Significant trends were determined for 6 of the 26 site records having 8 years or more record. In most cases, these trends resulted from construction and operation of upstream surface-water impoundments occurring during the period of record. Regional analysis of water-temperature characteristics at the 14 streamflow sites in the Piceance structural basin indicated similarities in water-temperature characteristics for a small range of measurement-site elevations. Evaluation of information content of the daily records indicated that less-than-daily measurement intervals should be considered, resulting in substantial savings in measurement and data-processing costs. (USGS)

The influence of changes in land use and landscape patterns on soil erosion in a watershed.

PubMed

Zhang, Shanghong; Fan, Weiwei; Li, Yueqiang; Yi, Yujun

2017-01-01

It is very important to have a good understanding of the relation between soil erosion and landscape patterns so that soil and water conservation in river basins can be optimized. In this study, this relationship was explored, using the Liusha River Watershed, China, as a case study. A distributed water and sediment model based on the Soil and Water Assessment Tool (SWAT) was developed to simulate soil erosion from different land use types in each sub-basin of the Liusha River Watershed. Observed runoff and sediment data from 1985 to 2005 and land use maps from 1986, 1995, and 2000 were used to calibrate and validate the model. The erosion modulus for each sub-basin was calculated from SWAT model results using the different land use maps and 12 landscape indices were chosen and calculated to describe the land use in each sub-basin for the different years. The variations in instead of the absolute amounts of the erosion modulus and the landscape indices for each sub-basin were used as the dependent and independent variables, respectively, for the regression equations derived from multiple linear regression. The results indicated that the variations in the erosion modulus were closely related to changes in the large patch index, patch cohesion index, modified Simpson's evenness index, and the aggregation index. From the regression equation and the corresponding landscape indices, it was found that watershed erosion can be reduced by decreasing the physical connectivity between patches, improving the evenness of the landscape patch types, enriching landscape types, and enhancing the degree of aggregation between the landscape patches. These findings will be useful for water and soil conservation and for optimizing the management of watershed landscapes. Copyright © 2016 Elsevier B.V. All rights reserved.

Major variation of paleo-maximum temperature and consolidation state within post Miocene forearc basin, central Japan

NASA Astrophysics Data System (ADS)

Kamiya, N.; Yamamoto, Y.; Takemura, T.

2015-12-01

Since forearc-basin evolve associated with development of the accretionary prisms, their geologic structures have clues to understanding the tectonic processes associated with plate subduction. We found a major difference in paleo-geothermal structure and consolidation states between the unconformity in the forearc basin in the Boso Peninsula, central Japan. The geology of the Boso Peninsula, central Japan is divided into three parts; Early Miocene and Late Miocene accretionary prisms in the southern part, the Hayama-Mineoka tectonic belt mainly composed of ophiolite in the middle part, and post-Middle Miocene forearc basin in the northern part. Sediments in the forearc basin are composed of 15-3Ma Miura Group and 3-0.6Ma Kazusa Group. Boundary of the two groups is the Kurotaki Unconformity formed about 3Ma, when convergent direction of the Philippine Sea Plate has been changed (Takahashi, 2006). Vitrinite reflectance (Ro) analyses were conducted and revealed that major variation of paleo-maximum temperature between the Miura and Kazusa groups. The maximum paleo-temperature in the Miura Group is estimated as 70-95˚C, whereas in the lower part of the Kazusa Group is less than 10-35˚C. Given 20˚C/km (Sakai et al, 2011) paleo-geothermal gradient, approximately 2000 m uplifting/erosion of the Miura Group is expected when the unconformity formed. To verify the amount of this uplifting/erosion, we are performing consolidation test of mudstone. [Reference] Takahashi, M., 2006, Tectonic Development of the Japanese Islands Controlled by Philippine Sea Plate Motion, Journal of Geography, 115, 116-123. Sakai R., Munakata M., Kimura H., Ichikawa Y., and Nakamura M., 2011, Study on Validation Method of Regional Groundwater Flow Model : Case Study for Boso Peninsula, JAEA-research 2010(66), 1-20, 1-2.

Climate Change Impacts on River Temperature in the Southeastern United States: A Case Study of the Tennessee River Basin

NASA Astrophysics Data System (ADS)

Cheng, Y.; Niemeyer, R. J.; Mao, Y.; Yearsley, J. R.; Nijssen, B.

2016-12-01

In the coming decades, climate change and population growth are expected to affect water and energy supply as well as demand in the southeastern United States. Changes in temperature and precipitation impact river flow and stream temperature with implications for hydropower generation, industrial and municipal water supply, cooling for thermo-electric power plants, agricultural irrigation, ecosystem functions and flood control. At the same time, water and energy demand are expected to change in response to temperature increase, population growth and changing crop water requirements. As part of a multi-institution study of the food-energy-water nexus in the southeastern U.S., we are developing coupled hydrological and stream temperature models that will be linked to water resources, power systems and crop models at a later stage. Here we evaluate the ability of our system to simulate water supply and stream temperature in the Tennessee River Basin using the Variable Infiltration Capacity (VIC) macroscale hydrology model coupled to the River Basin Model (RBM), a 1-D semi-Lagrangian river temperature model, which has recently been expanded with a two-layer reservoir temperature model. Simulations with VIC-RBM were performed for the Tennessee River Basin at 1/8-degree spatial resolution and a temporal resolution of 1 day or less. Reservoir releases were prescribed based on historic operating rules. In future iterations, these releases will be modeled directly by a water resources model that incorporates flood control, and power and agricultural water demands. We compare simulated flows, as well as stream and reservoir temperatures with observed flows and temperatures throughout the basin. In preparation for later stages of the project, we also perform a set of climate change sensitivity experiments to evaluate how changes in climate may impact river and reservoir temperature.

Dry season limnological conditions and basin geology exhibit complex relationships with δ13C and δ15N of carbon sources in four Neotropical floodplains.

PubMed

Zaia Alves, Gustavo H; Hoeinghaus, David J; Manetta, Gislaine I; Benedito, Evanilde

2017-01-01

Studies in freshwater ecosystems are seeking to improve understanding of carbon flow in food webs and stable isotopes have been influential in this work. However, variation in isotopic values of basal production sources could either be an asset or a hindrance depending on study objectives. We assessed the potential for basin geology and local limnological conditions to predict stable carbon and nitrogen isotope values of six carbon sources at multiple locations in four Neotropical floodplain ecosystems (Paraná, Pantanal, Araguaia, and Amazon). Limnological conditions exhibited greater variation within than among systems. δ15N differed among basins for most carbon sources, but δ13C did not (though high within-basin variability for periphyton, phytoplankton and particulate organic carbon was observed). Although δ13C and δ15N values exhibited significant correlations with some limnological factors within and among basins, those relationships differed among carbon sources. Regression trees for both carbon and nitrogen isotopes for all sources depicted complex and in some cases nested relationships, and only very limited similarity was observed among trees for different carbon sources. Although limnological conditions predicted variation in isotope values of carbon sources, we suggest the resulting models were too complex to enable mathematical corrections of source isotope values among sites based on these parameters. The importance of local conditions in determining variation in source isotope values suggest that isotopes may be useful for examining habitat use, dispersal and patch dynamics within heterogeneous floodplain ecosystems, but spatial variability in isotope values needs to be explicitly considered when testing ecosystem models of carbon flow in these systems.

Potential evaluation of CO2 storage and enhanced oil recovery of tight oil reservoir in the Ordos Basin, China.

PubMed

Tian, Xiaofeng; Cheng, Linsong; Cao, Renyi; Zhang, Miaoyi; Guo, Qiang; Wang, Yimin; Zhang, Jian; Cui, Yu

2015-07-01

Carbon -di-oxide (CO2) is regarded as the most important greenhouse gas to accelerate climate change and ocean acidification. The Chinese government is seeking methods to reduce anthropogenic CO2 gas emission. CO2 capture and geological storage is one of the main methods. In addition, injecting CO2 is also an effective method to replenish formation energy in developing tight oil reservoirs. However, exiting methods to estimate CO2 storage capacity are all based on the material balance theory. This was absolutely correct for normal reservoirs. However, as natural fractures widely exist in tight oil reservoirs and majority of them are vertical ones, tight oil reservoirs are not close. Therefore, material balance theory is not adaptive. In the present study, a new method to calculate CO2 storage capacity is presented. The CO2 effective storage capacity, in this new method, consisted of free CO2, CO2 dissolved in oil and CO2 dissolved in water. Case studies of tight oil reservoir from Ordos Basin was conducted and it was found that due to far lower viscosity of CO2 and larger solubility in oil, CO2 could flow in tight oil reservoirs more easily. As a result, injecting CO2 in tight oil reservoirs could obviously enhance sweep efficiency by 24.5% and oil recovery efficiency by 7.5%. CO2 effective storage capacity of Chang 7 tight oil reservoir in Longdong area was 1.88 x 10(7) t. The Chang 7 tight oil reservoir in Ordos Basin was estimated to be 6.38 x 10(11) t. As tight oil reservoirs were widely distributed in Songliao Basin, Sichuan Basin and so on, geological storage capacity of CO2 in China is potential.

Dry season limnological conditions and basin geology exhibit complex relationships with δ13C and δ15N of carbon sources in four Neotropical floodplains

PubMed Central

Hoeinghaus, David J.; Manetta, Gislaine I.; Benedito, Evanilde

2017-01-01

Studies in freshwater ecosystems are seeking to improve understanding of carbon flow in food webs and stable isotopes have been influential in this work. However, variation in isotopic values of basal production sources could either be an asset or a hindrance depending on study objectives. We assessed the potential for basin geology and local limnological conditions to predict stable carbon and nitrogen isotope values of six carbon sources at multiple locations in four Neotropical floodplain ecosystems (Paraná, Pantanal, Araguaia, and Amazon). Limnological conditions exhibited greater variation within than among systems. δ15N differed among basins for most carbon sources, but δ13C did not (though high within-basin variability for periphyton, phytoplankton and particulate organic carbon was observed). Although δ13C and δ15N values exhibited significant correlations with some limnological factors within and among basins, those relationships differed among carbon sources. Regression trees for both carbon and nitrogen isotopes for all sources depicted complex and in some cases nested relationships, and only very limited similarity was observed among trees for different carbon sources. Although limnological conditions predicted variation in isotope values of carbon sources, we suggest the resulting models were too complex to enable mathematical corrections of source isotope values among sites based on these parameters. The importance of local conditions in determining variation in source isotope values suggest that isotopes may be useful for examining habitat use, dispersal and patch dynamics within heterogeneous floodplain ecosystems, but spatial variability in isotope values needs to be explicitly considered when testing ecosystem models of carbon flow in these systems. PMID:28358822

Estimates of (239+240)Pu inventories in Gdańsk Bay and Gdańsk basin.

PubMed

Skwarzec, Bogdan; Strumińska, Dagmara I; Prucnal, Małgorzata

2003-01-01

This paper presents and discusses the results of (239+240)Pu determinations in different components of Gdańsk bay and Gdańsk basin ecosystem, as well as estimated sources and inventories of plutonium in these basins. The total plutonium (239+240)Pu activities deposited in Gdańsk bay and Gdańsk basin sediments are 1.18 TBq and 3.77 TBq, respectively. Two rivers, the Vistula and Neman rivers, and atmospheric fallout were distinguished as the main sources of plutonium in these basins. In seawater (with suspended matter included) there is about 2.33 GBq (239+240)Pu (0.2% of total activity) in Gdańsk bay and 9.92 GBq (239+240)Pu (0.3% of total activity) in Gdańsk basin. In both cases, 56% of (239+240)Pu is associated with suspended matter. Organisms contain 3.81 MBq in Gdańsk bay and 7.45 MBq (239+240)Pu in Gdańsk basin. From this value in Gdańsk bay 82.1% of plutonium is associated with zoobenthos, 13.6% with phytobenthos, 1.6% with phytoplankton, 1.5% with zooplankton and 1.2% with fish. In Gdańsk basin, 83.2% is associated with zoobenthos, 7.5% with phytobenthos, 3.6% with phytoplankton, 3.2% with zooplankton and 2.5% with fish.

The San Pedro Basin: A Case Study of US and Mexican Strategies to Connect Science to Societal Needs

NASA Astrophysics Data System (ADS)

Scott, R. L.; Goodrich, D. C.; Browning-Aiken, A.; Richter, H.; Varady, R.; Shuttleworth, W. J.

2007-05-01

The San Pedro River originates in northern Sonora near the town of Cananea and spans the U.S. - Mexico border into southeastern Arizona. The San Pedro Basin and perennial portions of its river support one of the most ecological diverse regions in the world. The regional groundwater aquifer which largely supports perennial flow and the associated riparian ecosystem is the primary water source for a number of communities, and for the Cananea copper mine in Sonora, which produces roughly two to three percent of the world's copper, and Ft. Huachuca, a major military installation in Arizona and the largest employer of southern Arizona. This presentation will discuss strategies and efforts over the past decade on both sides of the border to link hydrological, ecological and social sciences to aid elected officials and decision-makers in managing the basin, its growing population, and the water it so vitally depends upon. The disparate legal, cultural, economic and scientific environments, as well as the unequal degrees of decentralization and regional autonomy on the two sides of the border have resulted in distinct concerns and approaches to water resource management and varying rates of success. In the Sonoran portion of the basin water quality is the primary concern and in Arizona, water quantity is the major concern. The paper will report on sustained binational efforts and constraints encountered by researchers at the University of Arizona's NSF-funded SAHRA project and several NOAA-supported efforts in the basin region.

GIS and remote sensing techniques for the assessment of land use change impact on flood hydrology: the case study of Yialias basin in Cyprus

NASA Astrophysics Data System (ADS)

Alexakis, D. D.; Grillakis, M. G.; Koutroulis, A. G.; Agapiou, A.; Themistocleous, K.; Tsanis, I. K.; Michaelides, S.; Pashiardis, S.; Demetriou, C.; Aristeidou, K.; Retalis, A.; Tymvios, F.; Hadjimitsis, D. G.

2014-02-01

Floods are one of the most common natural disasters worldwide, leading to economic losses and loss of human lives. This paper highlights the hydrological effects of multi-temporal land use changes in flood hazard within the Yialias catchment area, located in central Cyprus. A calibrated hydrological model was firstly developed to describe the hydrological processes and internal basin dynamics of the three major subbasins, in order to study the diachronic effects of land use changes. For the implementation of the hydrological model, land use, soil and hydrometeorological data were incorporated. The climatic and stream flow data were derived from rain and flow gauge stations located in the wider area of the watershed basin. In addition, the land use and soil data were extracted after the application of object-oriented nearest neighbor algorithms of ASTER satellite images. Subsequently, the cellular automata (CA)-Markov chain analysis was implemented to predict the 2020 land use/land cover (LULC) map and incorporate it to the hydrological impact assessment. The results denoted the increase of runoff in the catchment area due to the recorded extensive urban sprawl phenomenon of the last decade.

A generalized land-use scenario generator: a case study for the Congo basin.

NASA Astrophysics Data System (ADS)

Caporaso, Luca; Tompkins, Adrian Mark; Biondi, Riccardo; Bell, Jean Pierre

2014-05-01

The impact of deforestation on climate is often studied using highly idealized "instant deforestation" experiments due to the lack of generalized deforestation scenario generators coupled to climate model land-surface schemes. A new deforestation scenario generator has been therefore developed to fulfill this role known as the deforestation ScenArio GEnerator, or FOREST-SAGE. The model produces distributed maps of deforestation rates that account for local factors such as proximity to transport networks, distance weighted population density, forest fragmentation and presence of protected areas and logging concessions. The integrated deforestation risk is scaled to give the deforestation rate as specified by macro-region scenarios such as "business as usual" or "increased protection legislation" which are a function of future time. FOREST-SAGE was initialized and validated using the MODerate Resolution Imaging Spectroradiometer Vegetation Continuous Field data. Despite the high cloud coverage of Congo Basin over the year, we were able to validate the results with high confidence from 2001 to 2010 in a large forested area. Furthermore a set of scenarios has been used to provide a range of possible pathways for the evolution of land-use change over the Congo Basin for the period 2010-2030.

Health and ecological risk assessment of heavy metals pollution in an antimony mining region: a case study from South China.

PubMed

Fei, Jiang-Chi; Min, Xiao-Bo; Wang, Zhen-Xing; Pang, Zhi-Hua; Liang, Yan-Jie; Ke, Yong

2017-12-01

In recent years, international research on the toxicity of the heavy metal, antimony, has gradually changed focus from early medical and pharmacological toxicology to environmental toxicology and ecotoxicology. However, little research has been conducted for sources identification and risk management of heavy metals pollution by long-term antimony mining activities. In this study, a large number of investigations were conducted on the temporal and spatial distribution of antimony and related heavy metal contaminants (lead, zinc, and arsenic), as well as on the exposure risks for the population for the Yuxi river basin in the Hunan province, China. The scope of the investigations included mine water, waste rock, tailings, agricultural soil, surface water, river sediments, and groundwater sources of drinking water. Health and ecological risks from exposure to heavy metal pollution were evaluated. The main pollution sources of heavy metals in the Yuxi River basin were analyzed. Remediation programs and risk management strategies for heavy metal pollution were consequently proposed. This article provides a scientific basis for the risk assessment and management of heavy metal pollution caused by antimony basin ore mining.

Coal and coalbed-methane resources in the Appalachian and Black Warrior basins: maps showing the distribution of coal fields, coal beds, and coalbed-methane fields: Chapter D.1 in Coal and petroleum resources in the Appalachian basin: distribution, geologic framework, and geochemical character

USGS Publications Warehouse

Trippi, Michael H.; Ruppert, Leslie F.; Milici, Robert C.; Kinney, Scott A.; Ruppert, Leslie F.; Ryder, Robert T.

2014-01-01

The study area for most reports in this volume is the Appalachian basin. The term “Appalachian basin study area” (shortened from “Appalachian basin geologic framework study area”) includes all of the Appalachian Basin Province (Province 67) and part of the neighboring Black Warrior Basin Province (Province 65) of Dolton and others (1995). The boundaries for these two provinces and the study area are shown on figure 1.

Modelling ecological flow regime: an example from the Tennessee and Cumberland River basins

USGS Publications Warehouse

Knight, Rodney R.; Gain, W. Scott; Wolfe, William J.

2012-01-01

Predictive equations were developed for 19 ecologically relevant streamflow characteristics within five major groups of flow variables (magnitude, ratio, frequency, variability, and date) for use in the Tennessee and Cumberland River basins using stepbackward regression. Basin characteristics explain 50% or more of the variation for 12 of the 19 equations. Independent variables identified through stepbackward regression were statistically significant in 78 of 304 cases (α > 0.0001) and represent four major groups: climate, physical landscape features, regional indicators, and land use. Of these groups, the regional and climate variables were the most influential for determining hydrologic response. Daily temperature range, geologic factor, and rock depth were major factors explaining the variability in 17, 15, and 13 equations, respectively. The equations and independent datasets were used to explore the broad relation between basin properties and streamflow and the implication of streamflow to the study of ecological flow requirements. Key results include a high degree of hydrologic variability among least disturbed Blue Ridge streams, similar hydrologic behaviour for watersheds with widely varying degrees of forest cover, and distinct hydrologic profiles for streams in different geographic regions. Published in 2011. This article is a US Government work and is in the public domain in the USA.

Biodiversity of cyanobacteria and green algae on monuments in the Mediterranean Basin: an overview.

PubMed

Macedo, Maria Filomena; Miller, Ana Zélia; Dionísio, Amélia; Saiz-Jimenez, Cesareo

2009-11-01

The presence and deteriorating action of micro-organisms on monuments and stone works of art have received considerable attention in the last few years. Knowledge of the microbial populations living on stone materials is the starting point for successful conservation treatment and control. This paper reviews the literature on cyanobacteria and chlorophyta that cause deterioration of stone cultural heritage (outdoor monuments and stone works of art) in European countries of the Mediterranean Basin. Some 45 case studies from 32 scientific papers published between 1976 and 2009 were analysed. Six lithotypes were considered: marble, limestone, travertine, dolomite, sandstone and granite. A wide range of stone monuments in the Mediterranean Basin support considerable colonization of cyanobacteria and chlorophyta, showing notable biodiversity. About 172 taxa have been described by different authors, including 37 genera of cyanobacteria and 48 genera of chlorophyta. The most widespread and commonly reported taxa on the stone cultural heritage in the Mediterranean Basin are, among cyanobacteria, Gloeocapsa, Phormidium and Chroococcus and, among chlorophyta, Chlorella, Stichococcus and Chlorococcum. The results suggest that cyanobacteria and chlorophyta colonize a wide variety of substrata and that this is related primarily to the physical characteristics of the stone surface, microclimate and environmental conditions and secondarily to the lithotype.

Taxonomic challenges in freshwater fishes: a mismatch between morphology and DNA barcoding in fish of the north-eastern part of the Congo basin.

PubMed

Decru, Eva; Moelants, Tuur; De Gelas, Koen; Vreven, Emmanuel; Verheyen, Erik; Snoeks, Jos

2016-01-01

This study evaluates the utility of DNA barcoding to traditional morphology-based species identifications for the fish fauna of the north-eastern Congo basin. We compared DNA sequences (COI) of 821 samples from 206 morphologically identified species. Best match, best close match and all species barcoding analyses resulted in a rather low identification success of 87.5%, 84.5% and 64.1%, respectively. The ratio 'nearest-neighbour distance/maximum intraspecific divergence' was lower than 1 for 26.1% of the samples, indicating possible taxonomic problems. In ten genera, belonging to six families, the number of species inferred from mtDNA data exceeded the number of species identified using morphological features; and in four cases indications of possible synonymy were detected. Finally, the DNA barcodes confirmed previously known identification problems within certain genera of the Clariidae, Cyprinidae and Mormyridae. Our results underscore the large number of taxonomic problems lingering in the taxonomy of the fish fauna of the Congo basin and illustrate why DNA barcodes will contribute to future efforts to compile a reliable taxonomic inventory of the Congo basin fish fauna. Therefore, the obtained barcodes were deposited in the reference barcode library of the Barcode of Life Initiative. © 2015 John Wiley & Sons Ltd.

Paleogeography of the upper Paleozoic basins of southern South America: An overview

NASA Astrophysics Data System (ADS)

Limarino, Carlos O.; Spalletti, Luis A.

2006-12-01

The paleogeographic evolution of Late Paleozoic basins located in southern South America is addressed. Three major types of basins are recognized: infracratonic or intraplate, arc-related, and retroarc. Intraplate basins (i.e., Paraná, Chaco-Paraná, Sauce Grande-Colorado, and La Golondrina) are floored by continental or quasi-continental crust, with low or moderate subsidence rates and limited magmatic and tectonic activity. Arc-related basins (northern and central Chile, Navidad-Arizaro, Río Blanco, and Calingasta-Uspallata basins and depocenters along Chilean Patagonia) show a very complex tectonic history, widespread magmatic activity, high subsidence rates, and in some cases metamorphism of Late Paleozoic sediments. An intermediate situation corresponds to the retroarc basins (eastern Madre de Dios, Tarija, Paganzo, and Tepuel-Genoa), which lack extensive magmatism and metamorphism but in which coeval tectonism and sedimentation rates were likely more important than those in the intraplate region. According to the stratigraphic distribution of Late Paleozoic sediments, regional-scale discontinuities, and sedimentation pattern changes, five major paleogeographic stages are proposed. The lowermost is restricted to the proto-Pacific and retroarc basins, corresponds to the Mississippian (stage 1), and is characterized by shallow marine and transitional siliciclastic sediments. During stage 2 (Early Pennsylvanian), glacial-postglacial sequences dominated the infracratonic (or intraplate) and retroarc basins, and terrigenous shallow marine sediments prevailed in arc-related basins. Stage 3 (Late Pennsylvanian-Early Cisuralian) shows the maximum extension of glacial-postglacial sediments in the Paraná and Sauce Grande-Colorado basins (intraplate region), whereas fluvial deposits interfingering with thin intervals of shallow marine sediments prevailed in the retroarc basins. To the west, arc-related basins were dominated by coastal to deep marine conditions (including turbiditic successions). In the Late Cisuralian (stage 4), important differences in sedimentation patterns are registered for the western arc-related basins and eastern intraplate basins. The former were locally dominated by volcaniclastic sediments or marine deposits, and the intraplate basins are characterized by shallow marine conditions punctuated by several episodes of deltaic progradation. Finally, in the Late Permian (stage 5), volcanism and volcaniclastic sedimentation dominated in basins located along the western South American margin. The intraplate basins in turn were characterized by T-R cycles composed of shallow marine, deltaic, and fluvial siliciclastic deposits.

Digging Deep: Is Lunar Mantle Excavated Around the Imbrium Basin?

NASA Astrophysics Data System (ADS)

Klima, R. L.; Bretzfelder, J.; Buczkowski, D.; Ernst, C. M.; Greenhagen, B. T.; Petro, N. E.; Shusterman, M. L.

2017-12-01

The Moon has experienced over a dozen impacts resulting in basins large enough to have excavated mantle material. With many of those basins concentrated on the lunar near side, and extensive regolith mixing since the lunar magma ocean crystallized, one might expect that some mantle material would have been found among the lunar samples on Earth. However, so far, no mantle clasts have been definitively identified in lunar samples [1]. From orbit, a number of olivine-bearing localities, potentially sourced from the mantle, have been identified around impact basins [2]. Based on analysis of near-infrared (NIR) and imaging data, [3] suggest that roughly 60% of these sites represent olivine from the mantle. If this is the case and the blocks are coherent and not extensively mixed into the regolith, these deposits should be ultramafic, containing olivine and/or pyroxenes and little to no plagioclase. In the mid-infrared, they would thus exhibit Christiansen features at wavelengths in excess of 8.5 μm, which has not been observed in global studies using the Diviner Lunar Radiometer [4]. We present an integrated study of the massifs surrounding the Imbrium basin, which, at over 1000 km wide, is large enough to have penetrated through the lunar crust and into the mantle. These massifs are clearly associated with the Imbrium basin-forming impact, but existing geological maps do not distinguish between whether they are likely ejecta or rather uplifted from beneath the surface during crustal rebound [5]. We examine these massifs using vis, NIR and Mid IR data to determine the relationships between and the bulk mineralogy of local lithologies. NIR data suggest that the massifs contain exposures of four dominant minerals: olivine, Mg-rich orthopyroxene, a second low-Ca pyroxene, and anorthite. Mid IR results suggest that though many of these massifs are plagioclase-rich, portions of some may be significantly more mafic. We will present our growing mineralogical map of the Imbrium basin perimeter, and discuss implications for the sub-basin stratigraphy and potential excavation of mantle material. [1] Shearer et al. (2015) MAPS 50, 1449. [2] Yamamoto et al. (2012) GRL 39, L13201. [3] Ohtake et al. (2017) New Views of the Moon 2 - Europe, Abstract #6016 [4] Greenhagen et al. (2010) Science 329, 1507. [5] Wilhelms D. E. et al. (1987), USGS Lunar map.

Impact of Climate Change on Water Resources in the Guadalquivir River Basin

NASA Astrophysics Data System (ADS)

Yeste Donaire, P.; García-Valdecasas-Ojeda, M.; Góngora García, T. M.; Gámiz-Fortis, S. R.; Castro-Diez, Y.; Esteban-Parra, M. J.

2017-12-01

Climate change has lead to a decrease of precipitation and an increase of temperature in the Mediterranean Basin during the last fifty years. These changes will be more intense over the course of the 21thcentury according to global climate projections. As a consequence, water resources are expected to decrease, particularly in the Guadalquivir River Basin. This study focuses on the hydrological response of the Guadalquivir River Basin to the climate change. For this end, firstly, the implementation of the Variable Infiltration Capacity (VIC) model in the Basin was carried out. The VIC model was calibrated with a dataset of daily precipitation, temperature and streamflow for the period 1990-2000. Precipitation and temperature data were extracted from SPAIN02, a dataset that covers the Peninsular Spain at 0.11º of spatial resolution. Streamflow data were gathered for a representative subset of gauging stations in the basin. These data were provided by the Spanish Center for Public Work Experimentation and Study (CEDEX). Subsequently, the VIC model was validated for the period 2000-2005 in order to verify that the model outputs fit well with the observational data. After the validation of the VIC model for present climate, secondly, the effect of climate change on the Guadalquivir River Basin will be analyzed by developing several simulations of the streamflow for future climate. Precipitation and temperature data will be obtained in this case from future projections coming from high resolution (at 0.088º) simulations carried out with the Weather Research and Forecasting (WRF) model for the Iberian Peninsula. These last simulations will be driven under two different Representative Concentration Pathway (RCP) scenarios, RCP 4.5 and RCP 8.5 for the periods 2021-50 and 2071-2100. The first results of this work show that the VIC model outputs are in good agreement with the observed streamflow for both the calibration and validation periods. In the context of climate change, a generalized decrease in surface and subsurface water resources is expected in the Guadalquivir River Basin. All these results will be of interest for water policy makers and practitioners in the next decades. ACKNOWLEDGEMENTS: This work has been financed by the projects P11-RNM-7941 (Junta de Andalucía) and CGL2013-48539-R (MINECO-Spain, FEDER).

Towards a mechanistic understanding of the linkages between PETM climate modulation and stratigraphy, as discerned from the Piceance Basin, CO, USA

NASA Astrophysics Data System (ADS)

Barefoot, E. A.; Nittrouer, J. A.; Foreman, B.; Moodie, A. J.; Dickens, G. R.

2017-12-01

The Paleocene-Eocene Thermal Maximum (PETM) was a period of rapid climatic change when global temperatures increased by 5-8˚C in as little as 5 ka. It has been hypothesized that by drastically enhancing the hydrologic cycle, this temperature change significantly perturbed landscape dynamics over the ensuing 200 ka. Much of the evidence documenting hydrological variability derives from studies of the stratigraphic record, which is interpreted to encode a system-clearing event in fluvial systems worldwide during and after the PETM. For example, in the Piceance Basin of Western Colorado, it is hypothesized that intensification of monsoons due to PETM warming caused an increase in sediment flux to the basin. The resulting stratigraphy records a modulation of the sedimentation rate, where the PETM interval is represented by a laterally extensive sheet sand positioned between units dominated by floodplain muds. The temporal interval, the sediment provenance history, as well as the tectonic history of the PETM in the Piceance Basin are all well-constrained, leaving climate as the most significant allogenic forcing in the Piceance Basin during the PETM. However, the precise nature of landscape change that link climate forcing by the PETM to modulation of the sedimentation rate in this basin remains to be demonstrated. Here, we present a simple stratigraphic numerical model coupled with a conceptual source-to-sink framework to test the impact of a suite of changing upstream boundary conditions on the fluvial system. In the model, climate-related variables force changes in flow characteristics such as sediment transport, slope, and velocity, which determine the resultant floodplain stratigraphy. The model is based on mathematical relations that link bankfull geometry and water discharge, impacting the lateral migration rate of the channel, sediment transport rate, and avulsion frequency, thereby producing a cross-section of basin stratigraphy. In this way, we simulate a raft of plausible, and mutually exclusive, climate-change scenarios for the case study of the Piceance Basin during the PETM, which may be compared to the stratigraphic record through field observation. The method described here represents a step towards connecting the impacts of global climate change to fluvial systems and sedimentation dynamics.

Modeling of extreme freshwater outflow from the north-eastern Japanese river basins to western Pacific Ocean

NASA Astrophysics Data System (ADS)

Troselj, Josko; Sayama, Takahiro; Varlamov, Sergey M.; Sasaki, Toshiharu; Racault, Marie-Fanny; Takara, Kaoru; Miyazawa, Yasumasa; Kuroki, Ryusuke; Yamagata, Toshio; Yamashiki, Yosuke

2017-12-01

This study demonstrates the importance of accurate extreme discharge input in hydrological and oceanographic combined modeling by introducing two extreme typhoon events. We investigated the effects of extreme freshwater outflow events from river mouths on sea surface salinity distribution (SSS) in the coastal zone of the north-eastern Japan. Previous studies have used observed discharge at the river mouth, as well as seasonally averaged inter-annual, annual, monthly or daily simulated data. Here, we reproduced the hourly peak discharge during two typhoon events for a targeted set of nine rivers and compared their impact on SSS in the coastal zone based on observed, climatological and simulated freshwater outflows in conjunction with verification of the results using satellite remote-sensing data. We created a set of hourly simulated freshwater outflow data from nine first-class Japanese river basins flowing to the western Pacific Ocean for the two targeted typhoon events (Chataan and Roke) and used it with the integrated hydrological (CDRMV3.1.1) and oceanographic (JCOPE-T) model, to compare the case using climatological mean monthly discharges as freshwater input from rivers with the case using our hydrological model simulated discharges. By using the CDRMV model optimized with the SCE-UA method, we successfully reproduced hindcasts for peak discharges of extreme typhoon events at the river mouths and could consider multiple river basin locations. Modeled SSS results were verified by comparison with Chlorophyll-a distribution, observed by satellite remote sensing. The projection of SSS in the coastal zone became more realistic than without including extreme freshwater outflow. These results suggest that our hydrological models with optimized model parameters calibrated to the Typhoon Roke and Chataan cases can be successfully used to predict runoff values from other extreme precipitation events with similar physical characteristics. Proper simulation of extreme typhoon events provides more realistic coastal SSS and may allow a different scenario analysis with various precipitation inputs for developing a nowcasting analysis in the future.

Characterizing directional variations in long-period ground motion amplifications in the Kanto Basin, Japan

NASA Astrophysics Data System (ADS)

Mukai, Y.; Furumura, T.; Maeda, T.

2017-12-01

In the Kanto Basin (including Tokyo in Japan), the long-period (T=3-10 s) ground motions are strongly developed when large earthquakes occur nearby. The amplitude of the long-period ground motion in the basin varies strongly among earthquakes; it is tremendous from the earthquakes in Niigata (northwest of Kanto), but is several times weaker from the earthquakes in Tohoku (north of Kanto). In this study, we examined the cause of such azimuthal-dependent amplitude variation for the 2004 Niigata Chuetsu (M6.8) and the 2011 Fukushima Hamadori (M7.0) earthquake based on numerical simulations of seismic wave propagation by the finite-difference method. We first examined the non-isotropic source-radiation effect of these events. By performing numerical simulations for different strike angles of these source faults, significant variation in amplitude of the long-period ground motions were observed in Tokyo for both the events. Among tested strike angles, the source of the 2004 event (strike = 212 deg.) produced the largest long-period ground motion due to strong radiation of surface wave towards the Kanto Basin, while the 2011 event (strike = 132 deg.) produced the least. The minimum-to-maximum ratio of their amplitudes with respect to strike angle is about 2 and 1.3, respectively. These investigations suggest the source radiation effect considerably contributes to the variations of the long-period ground motions. We then examined the effect of the 3D structure of the Kanto Basin on the generation of the long-period ground motion. For the 2004 event, we found that the long-period signal first arrives at the central Tokyo from the western edge of the Kanto Basin. Then, later signals containing both the Rayleigh and Love waves were amplified dramatically due to the localized low-velocity structure to the northwestern part of the basin. On the other hand, in the case of the 2011 event, the seismic waves propagating towards the basin were dissipated significantly as it travels over the ridge structure of the basement in the northern part of the basin, where the seismic wave speed is faster than the surroundings. Therefore, the large variation of the long-period ground motion among earthquakes occurs due to the combined effects of source radiation and propagation properties in the 3D heterogeneous structure of the Kanto Basin.

Analysis of gravity anomalies in the Ulleung Basin (East Sea/Sea of Japan) and its implications for the crustal structure of rift-dominated back-arc basin

NASA Astrophysics Data System (ADS)

Kim, Yoon-Mi; Lee, Sang-Mook

2018-01-01

The Ulleung Basin (UB), one of three major basins in the East Sea/Sea of Japan, is considered to represent a continental-rifting end-member of back-arc basin system, but is much less understood compared to the nearby Yamato Basin (YB) and Japan Basin (JB). This study examines the gravity anomalies of the UB since the variation in crustal thickness can provide important insights on the mode of extension during basin opening. Our analysis shows that the Moho depth (from the sea surface) varies from 16 km at the basin center to 22 km at the edges. However, within the central part of the basin, the crustal thickness (not including sediment) is more or less the same (10-12 km), by varying only about 10-20% of the total thickness, contrary to the previous suggestions. Our finding of anomalous but uniformly thick crust is consistent with the recent seismic results from the YB (14 km on average). A mantle residual gravity anomaly high (∼20 mGal) exists in the northeastern part of the UB. This feature is interpreted as the location of maximum extension (slightly thinner crust by ∼1 km). Together with another moderate gravity high to the southwest, the two anomalies form a NNE-SSW line, which corresponds to the direction of the major tectonic structures of the Korean Peninsula. We argue that the a massive magmatic emplacement took place extensively in the lower crust of the UB during the opening, significantly increasing its overall thickness to almost twice as that of the JB where a mid-ocean-ridge style seafloor spreading occurred. Two important post-opening processes took place after the formation of uniformly thick crust: post-rift volcanic intrusions in the north, especially in its northeast sections but had little effect on the residual gravity anomaly itself, and the deflection of crust in response to differential sediment loading towards the south, producing the median high in the basement in response to the flexural bending. We also conducted a simple test to examine what effect the variations in the mantle potential temperature and degree of extension may have on the gravity anomaly. According to our model, the latter case is much more likely to cause the variations in gravity anomaly than the former.

Eliciting Students' Understanding of a Local Socioscientific Issue through the Use of Critical Response Pedagogies

ERIC Educational Resources Information Center

Karahan, Engin; Andzenge, Senenge T.; Roehrig, Gillian

2017-01-01

This study introduces a critical response pedagogy (CRP), an arts-based critical technique to facilitate meaningful dialogue in focus group settings, to secondary school science education students to engage them in discussion about sediment and chemical load in their local river basin community. Using a holistic single case design, twenty-two 11th…

A method to identify the variable ecosystem services relationship across time: a case study on Yanhe Basin, China

Treesearch

Zhenmin Zheng; Bojie Fu; Haitang Hu; Ge Sun

2014-01-01

Ecosystem services are increasingly recognized as the foundations of a well-functioning society. Large-scale ecological restoration projects have been implemented around China with the goal of restoring and sustaining ecosystem services, especially in vulnerable semi-arid regions where soil and water resources are most stressed due to historic human activities. The...

Tectono-thermal History of the Southern Nenana Basin, Interior Alaska: Implications for Conventional and Unconventional Hydrocarbon Exploration

NASA Astrophysics Data System (ADS)

Dixit, N. C.; Hanks, C. L.

2014-12-01

The Tertiary Nenana basin of Interior Alaska is currently the focus of both new oil exploration and coalbed methane exploitation and is being evaluated as a potential CO2sequestration site. The basin first formed as a Late Paleocene extensional rift with the deposition of oil and gas-prone, coal-bearing non-marine sediments with excellent source potential. Basin inversion during the Early Eocene-Early Oligocene times resulted in folding and erosion of higher stratigraphic levels, forming excellent structural and stratigraphic traps. Initiation of active faulting on its eastern margin in the middle Oligocene caused slow tectonic subsidence that resulted in the deposition of reservoir and seal rocks of the Usibelli Group. Onset of rapid tectonic subsidence in Pliocene that continues to the present-day has provided significant pressure and temperature gradient for the source rocks. Apatite fission-track and vitrinite reflectance data reveals two major paleo-thermal episodes: Late Paleocene to Early Eocene (60 Ma to 54.8 Ma) and Late Miocene to present-day (7 Ma to present). These episodes of maximum paleotemperatures have implications for the evolution of source rock maturity within the basin. In this study, we are also investigating the potential for coalbed methane production from the Late Paleocene coals via injection of CO2. Our preliminary analyses demonstrate that 150 MMSCF of methane could be produced while 33000 tonnes of CO2 per injection well (base case of ~9 years) can be sequestered in the vicinity of existing infrastructure. However, these volumes of sequestered CO2and coal bed methane recovery are estimates and are sensitive to the reservoir's geomechanical and flow properties. Keywords: extensional rift, seismic, subsidence, thermal history, fission track, vitrinite reflectance, coal bed methane, Nenana basin, CO2 sequestration

Hydrological Impacts of Land Use Change and Climate Variability in the Headwater Region of the Heihe River Basin, Northwest China

PubMed Central

Zhang, Ling; Nan, Zhuotong; Xu, Yi; Li, Shuo

2016-01-01

Land use change and climate variability are two key factors impacting watershed hydrology, which is strongly related to the availability of water resources and the sustainability of local ecosystems. This study assessed separate and combined hydrological impacts of land use change and climate variability in the headwater region of a typical arid inland river basin, known as the Heihe River Basin, northwest China, in the recent past (1995–2014) and near future (2015–2024), by combining two land use models (i.e., Markov chain model and Dyna-CLUE) with a hydrological model (i.e., SWAT). The potential impacts in the near future were explored using projected land use patterns and hypothetical climate scenarios established on the basis of analyzing long-term climatic observations. Land use changes in the recent past are dominated by the expansion of grassland and a decrease in farmland; meanwhile the climate develops with a wetting and warming trend. Land use changes in this period induce slight reductions in surface runoff, groundwater discharge and streamflow whereas climate changes produce pronounced increases in them. The joint hydrological impacts are similar to those solely induced by climate changes. Spatially, both the effects of land use change and climate variability vary with the sub-basin. The influences of land use changes are more identifiable in some sub-basins, compared with the basin-wide impacts. In the near future, climate changes tend to affect the hydrological regimes much more prominently than land use changes, leading to significant increases in all hydrological components. Nevertheless, the role of land use change should not be overlooked, especially if the climate becomes drier in the future, as in this case it may magnify the hydrological responses. PMID:27348224

On the Edge: the Impact of Climate Change, Climate Extremes, and Climate-driven Disturbances on the Food-Energy-Water Nexus in the Colorado River Basin

NASA Astrophysics Data System (ADS)

Bennett, K. E.; McDowell, N. G.; Tidwell, V. C.; Xu, C.; Solander, K.; Jonko, A. K.; Wilson, C. J.; Middleton, R. S.

2016-12-01

The Colorado River Basin (CRB) is a critical watershed in terms of vulnerability to climate change and supporting the food-energy-water nexus. Climate-driven disturbances in the CRB—including wildfire, drought, and pests—threaten the watershed's ability to reliably support a wide array of ecosystem services while meeting the interrelated demands of the food-energy-water nexus. Our work illustrates future changes for upper Colorado River headwater basins using the Variable Infiltration Capacity hydrologic model driven by downscaled CMIP5 global climate data coupled with pseudo-dynamic vegetation shifts associated with changing fire and drought conditions. We examine future simulated streamflow within the context of an operational model framework to consider the impacts on water operators and managers who rely upon the timely and continual delivery of streamflow. We focus on results for a large case study basin within the CRB—the San Juan River—showing future scenarios where this ecosystem is pushed towards the extremes. Our findings illustrate that landscape change in the CRB cause delayed snowmelt and increased evapotranspiration from shrublands, which leads to increases in the frequency and magnitude of both droughts and floods within disturbed systems. By 2080, coupled climate and landscape change produces a dramatically altered hydrograph resulting in larger peak flows, reduced lower flows, and lower overall streamflow. Operationally, this results in increased future water delivery challenges and lower reservoir storages driven by changes in the headwater basins. Ultimately, our work shows that the already-stressed CRB ecosystem could, in the future, be pushed over a tipping point, significantly impacting the basin's ability to reliably supply water for food, energy, and urban uses.

Hydrological Impacts of Land Use Change and Climate Variability in the Headwater Region of the Heihe River Basin, Northwest China.

PubMed

Zhang, Ling; Nan, Zhuotong; Xu, Yi; Li, Shuo

2016-01-01

Land use change and climate variability are two key factors impacting watershed hydrology, which is strongly related to the availability of water resources and the sustainability of local ecosystems. This study assessed separate and combined hydrological impacts of land use change and climate variability in the headwater region of a typical arid inland river basin, known as the Heihe River Basin, northwest China, in the recent past (1995-2014) and near future (2015-2024), by combining two land use models (i.e., Markov chain model and Dyna-CLUE) with a hydrological model (i.e., SWAT). The potential impacts in the near future were explored using projected land use patterns and hypothetical climate scenarios established on the basis of analyzing long-term climatic observations. Land use changes in the recent past are dominated by the expansion of grassland and a decrease in farmland; meanwhile the climate develops with a wetting and warming trend. Land use changes in this period induce slight reductions in surface runoff, groundwater discharge and streamflow whereas climate changes produce pronounced increases in them. The joint hydrological impacts are similar to those solely induced by climate changes. Spatially, both the effects of land use change and climate variability vary with the sub-basin. The influences of land use changes are more identifiable in some sub-basins, compared with the basin-wide impacts. In the near future, climate changes tend to affect the hydrological regimes much more prominently than land use changes, leading to significant increases in all hydrological components. Nevertheless, the role of land use change should not be overlooked, especially if the climate becomes drier in the future, as in this case it may magnify the hydrological responses.

Fueling plankton production by a meandering frontal jet: a case study for the Alboran Sea (Western Mediterranean).

PubMed

Oguz, Temel; Macias, Diego; Garcia-Lafuente, Jesus; Pascual, Ananda; Tintore, Joaquin

2014-01-01

A three dimensional biophysical model was employed to illustrate the biological impacts of a meandering frontal jet, in terms of efficiency and persistency of the autotrophic frontal production, in marginal and semi-enclosed seas. We used the Alboran Sea of the Western Mediterranean as a case study. Here, a frontal jet with a width of 15-20 km, characterized by the relatively low density Atlantic water mass, flows eastward within the upper 100 m as a marked meandering current around the western and the eastern anticyclonic gyres prior to its attachment to the North African shelf/slope topography of the Algerian basin. Its inherent nonlinearity leads to the development of a strong ageostrophic cross-frontal circulation that supplies nutrients into the nutrient-starved euphotic layer and stimulates phytoplankton growth along the jet. Biological production is larger in the western part of the basin and decreases eastwards with the gradual weakening of the jet. The higher production at the subsurface levels suggests that the Alboran Sea is likely more productive than predicted by the satellite chlorophyll data. The Mediterranean water mass away from the jet and the interiors of the western and eastern anticyclonic gyres remain unproductive.

Basins in ARC-continental collisions

USGS Publications Warehouse

Draut, Amy E.; Clift, Peter D.; Busby, Cathy; Azor, Antonio

2012-01-01

Arc-continent collisions occur commonly in the plate-tectonic cycle and result in rapidly formed and rapidly collapsing orogens, often spanning just 5-15 My. Growth of continental masses through arc-continent collision is widely thought to be a major process governing the structural and geochemical evolution of the continental crust over geologic time. Collisions of intra-oceanic arcs with passive continental margins (a situation in which the arc, on the upper plate, faces the continent) involve a substantially different geometry than collisions of intra-oceanic arcs with active continental margins (a situation requiring more than one convergence zone and in which the arc, on the lower plate, backs into the continent), with variable preservation potential for basins in each case. Substantial differences also occur between trench and forearc evolution in tectonically erosive versus tectonically accreting margins, both before and after collision. We examine the evolution of trenches, trench-slope basins, forearc basins, intra-arc basins, and backarc basins during arc-continent collision. The preservation potential of trench-slope basins is low; in collision they are rapidly uplifted and eroded, and at erosive margins they are progressively destroyed by subduction erosion. Post-collisional preservation of trench sediment and trench-slope basins is biased toward margins that were tectonically accreting for a substantial length of time before collision. Forearc basins in erosive margins are usually floored by strong lithosphere and may survive collision with a passive margin, sometimes continuing sedimentation throughout collision and orogeny. The low flexural rigidity of intra-arc basins makes them deep and, if preserved, potentially long records of arc and collisional tectonism. Backarc basins, in contrast, are typically subducted and their sediment either lost or preserved only as fragments in melange sequences. A substantial proportion of the sediment derived from collisional orogenesis ends up in the foreland basin that forms as a result of collision, and may be preserved largely undeformed. Compared to continent-continent collisional foreland basins, arc-continent collisional foreland basins are short-lived and may undergo partial inversion after collision as a new, active continental margin forms outboard of the collision zone and the orogen whose load forms the basin collapses in extension.

Land factors affecting soil erosion during snow melting: a case study from Lebanon

NASA Astrophysics Data System (ADS)

Darwich, Talal

2014-05-01

Soil erosion is one of the major problems facing the mountainous agricultural lands in Lebanon. In order to assess the land factors acting on soil erosion; a study was conducted in the upper watershed of Ibrahim River in the spring months of April, May and June. Water and bed load sediments from six locations alimented by six sub-basins were sampled. Four sub-basins (1, 2, 3 and 6) were dominated by agricultural lands while lands in sub-basins 4 and 7 were occupied by grassland and bare soils. The highest quantities of suspended sediments were found in waters originating from watersheds dominated by agricultural lands, such as Location 2 (713.72 mg L-1 in April 2012). Low clay content and the combination of land occupation (orchards = 71%) and slope (20.7 degrees) caused this ecosystem disturbance. Locations 1, 2, 3 and 6 were alimented by runoff water due to the melting of the snow. For this, the concentrations of sediments decreased by 4 fold between April and May in sub-basin 1 and by 11-14 fold in sub-basins 2, 3 and 6. Globally, some 1669.4 tons of sediments were delivered in the upper river during April. Bed load sediments were separated into 4 classes according to their size. The size of the particles found in the bed load reflected to a large extent the type of soils surrounding the watershed. The range of sand in the regions surrounding locations 6 and 7 was 64% and 82%, while the average in the bed load was 80.9% and 78.25% respectively. The silt content in locations 2, 3 and 5 was well reflected in the concentrations of silt in the bed load. In bed load samples, the exchangeable potassium ranged from 70-250 mg kg-1 in sub-basins dominated by agricultural lands against 20-50 mg kg-1 in sub-basins dominated by grassland and bare rocks. Further quantitative studies need to be conducted especially during the first rains to fully estimate the water load sediments after a prolonged dry season, characterizing the east Mediterranean. Action must be taken for land conservation by improving the farmer's practices, modifying the frequency of plowing and introducing no tillage beside the maintenance of terraces. Keywords: Mountains, erosion, sediments, East Mediterranean, river, bed load quality.

[Effect of hydrochemistry characteristics under impact of human activity: a case study in the upper reaches of the Xijiang River basin].

PubMed

Yu, Shil; Sun, Ping-an; Du, Wen-yue; He, Shi-yi; Li, Rui

2015-01-01

In this paper, observation and sampling were taken three times a month in a hydrological year for three typical sections of the middle and upper reaches of the Xijiang River basin, based on the data of hydrochemistry and flow, the article mainly discusses the evolution process of hydrochemistry in river under natural process and impact of human activity. Hydrochemical characteristics of 116. samples were analyzed in the study area. The hydrochemistry type in the middle and upper reaches of the Xijiang River basin belonged to HCO3- -Ca2+ type, and the chemical weathering type mainly came from carbonate rock weathering. Ca2+ and HCO3- were the main cations and anions, which reflected that hydrochemical characteristics of river in karst area mainly affected by the dissolution of carbonate rock. Na, Mg2, Ca2+ and Cl- mainly affected by natural conditions, the impact of human activity was little. K+, NO3-, SO4(2-) and HCO3- were affected by human activity in different degrees, and it showed different influence ways. This study had an important significance for the change of river hydrochemistry, water quality characteristics, and the effect on substance transported fluxes in the downstream of Pearl River and water quality protection in South China Monsoon Area.

Understanding the impacts of climate change and human activities on streamflow: a case study of the Soan River basin, Pakistan

NASA Astrophysics Data System (ADS)

Shahid, Muhammad; Cong, Zhentao; Zhang, Danwu

2017-09-01

Climate change and land use change are the two main factors that can alter the catchment hydrological process. The objective of this study is to evaluate the relative contribution of climate change and land use change to runoff change of the Soan River basin. The Mann-Kendal and the Pettit tests are used to find out the trends and change point in hydroclimatic variables during the period 1983-2012. Two different approaches including the abcd hydrological model and the Budyko framework are then used to quantify the impact of climate change and land use change on streamflow. The results from both methods are consistent and show that annual runoff has significantly decreased with a change point around 1997. The decrease in precipitation and increases in potential evapotranspiration contribute 68% of the detected change while the rest of the detected change is due to land use change. The land use change acquired from Landsat shows that during post-change period, the agriculture has increased in the Soan basin, which is in line with the positive contribution of land use change to runoff decrease. This study concludes that aforementioned methods performed well in quantifying the relative contribution of land use change and climate change to runoff change.

Valuing investments in sustainable land management in the Upper Tana River basin, Kenya.

PubMed

Vogl, Adrian L; Bryant, Benjamin P; Hunink, Johannes E; Wolny, Stacie; Apse, Colin; Droogers, Peter

2017-06-15

We analyze the impacts of investments in sustainable land use practices on ecosystem services in the Upper Tana basin, Kenya. This work supports implementation of the Upper Tana-Nairobi Water Fund, a public-private partnership to safeguard ecosystem service provision and food security. We apply an integrated modelling framework, building on local knowledge and previous field- and model-based studies, to link biophysical landscape changes at high temporal and spatial resolution to economic benefits for key actors in the basin. The primary contribution of this study is that it a) presents a comprehensive analysis for targeting interventions that takes into account stakeholder preferences, local environmental and socio-economic conditions, b) relies on detailed, process-based, biophysical models to demonstrate the biophysical return on those investments for a practical, decision-driven case, and c) in close collaboration with downstream water users, links those biophysical outputs to monetary metrics, including: reduced water treatment costs, increased hydropower production, and crop yield benefits for agricultural producers in the conservation area. This study highlights the benefits and trade-offs that come with conducting participatory research as part of a stakeholder engagement process: while results are more likely to be decision-relevant within the local context, navigating stakeholder expectations and data limitations present ongoing challenges. Copyright © 2016 Elsevier Ltd. All rights reserved.

Monitoring Rainfall by Combining Ground-based Observed Precipitation and PERSIANN Satellite Product (Case Study Area: Lake Urmia Basin)

NASA Astrophysics Data System (ADS)

Abrishamchi, A.; Mirshahi, A.

2015-12-01

The global coverage, quick access, and appropriate spatial-temporal resolution of satellite precipitation data renders the data appropriate for hydrologic studies, especially in regions with no sufficient rain-gauge network. On the other hand, satellite precipitation products may have major errors. The present study aims at reduction of estimation error of the PERSIANN satellite precipitation product. Bayesian logic employed to develop a statistical relationship between historical ground-based and satellite precipitation data. This relationship can then be used to reduce satellite precipitation product error in near real time, when there is no ground-based precipitation observation. The method was evaluated in the Lake Urmia basin with a monthly time scale; November to May of 2000- 2008 for the purpose of model development and two years of 2009 and 2010 for the validation of the established relationships. Moreover, Kriging interpolation method was employed to estimate the average rainfall in the basin. Furthermore, to downscale the satellite precipitation product from 0.25o to 0.05o, data-location downscaling algorithm was used. In 76 percent of months, the final product, compared with the satellite precipitation, had less error during the validation period. Additionally, its performance was marginally better than adjusted PERSIANN product.

An approach of understanding acid volcanics and tuffaceous volcaniclastics from field studies: A case from Tadpatri Formation, Proterozoic Cuddapah basin, Andhra Pradesh, India

NASA Astrophysics Data System (ADS)

Goswami, Sukanta; Upadhyay, P. K.; Bhagat, Sangeeta; Zakaulla, Syed; Bhatt, A. K.; Natarajan, V.; Dey, Sukanta

2018-03-01

The lower stratigraphic part of the Cuddapah basin is marked by mafic and felsic volcanism. Tadpatri Formation consists of a greater variety of rock types due to bimodal volcanism in the upper part. Presence of bimodal volcanism is an indication of continental rift setting. Various genetic processes involved in the formation of such volcanic sequence result in original textures which are classified into volcaniclastic and coherent categories. Detailed and systematic field works in Tadpatri-Tonduru transect of SW Cuddapah basin have provided information on the physical processes producing this diversity of rock types. Felsic volcanism is manifested here with features as finger print of past rhyolite-dacite eruptions. Acid volcanics, tuffs and associated shale of Tadpatri Formation are studied and mapped in the field. With supporting subordinate studies on geochemistry, mineralogy and petrogenesis of the volcanics to validate field features accurately, it is understood that volcanism was associated with rifting and shallow marine environmental condition. Four facies (i.e., surge, flow, fall and resedimented volcaniclastic) are demarcated to describe stratigraphic units and volcanic history of the mapped area. The present contribution focuses on the fundamental characterization and categorization of field-based features diagnostic of silica-rich volcanic activities in the Tadpatri Formation.

Full 40 km crustal reflection seismic datasets in several Indonesian basins

NASA Astrophysics Data System (ADS)

Dinkelman, M. G.; Granath, J. W.; Christ, J. M.; Emmet, P. A.; Bird, D. E.

2010-12-01

Long offset, deep penetration regional 2D seismic data sets have been acquired since 2002 by GX Technology in a number of regions worldwide (www.iongeo.com/Data_Libraries/Spans/). Typical surveys consist of 10+ lines located to image specific critical aspects of basin structure. Early surveys were processed to 20 km, but more recent ones have extended to 40-45 km from 16 sec records. Pre-stack time migration is followed by pre-stack depth migration using gravity and in some cases magnetic modeling to constrain the velocity structure. We illustrate several cases in the SE Asian and Australasian area. In NatunaSPAN™ two generations of inversion can be distinguished, one involving Paleogene faults with Neogene inversion and one involving strike slip-related uplift in the West Natuna Basin. Crustal structure in the very deep Neogene East Natuna Basin has also been imaged. The JavaSPAN™ program traced Paleogene sediments onto oceanic crust of the Flores Sea, thus equating back arc spreading there to the widespread Eocene extension. It also imaged basement in the Makassar Strait beneath as much as 6 km of Cenozoic sedimentary rocks that accumulated Eocene rift basins (the North and South Makassar basins) on the edge of Sundaland, the core of SE Asia. The basement is seismically layered: a noisy upper crust overlies a prominent 10 km thick transparent zone, the base of which marks another change to slightly noisier reflectivity. Eocene normal faults responsible for the opening of extensional basins root in the top of the transparent layer which may be Moho or a brittle-ductile transition within the extended continental crust. Of particular significance is the first image of thick Precambrian basins comprising the bulk of continental crust under the Arafura Sea in the ArafuraSPAN™ program. Four lines some 1200 km long located between Australia and New Guinea on the Arafura platform image a thin Phanerozoic section overlying a striking Precambrian basement composed of sedimentary and burial metamorphosed sedimentary rock that we divide into two packages on the basis of seismic character. The upper is 8-15 km of undeformed late Precambrian sediments the top of which ties Eocambrian rocks in wells in offshore New Guinea. This package appears to correlate to the Wessel Group in northern Australia. The lower package is composed of 10-15 km of strongly bedded, presumably burial metamorphosed rocks that make up the bulk of the lower crust. These may equate to any of a number of northern Australian Mesoproterozoic basins. This lower package offlaps ‘pods’ of seismically transparent basement (?Paleoproterozoic or Archean) that make up at most the lowermost 15 km of the 40 km PSDM line. Both Precambrian packages appear to be craton-margin sedimentary wedges, the younger overlapping the older. The SE extent of the lowermost package is deformed in a thrust system which may mark the event that detached it from its original underlying oceanic or transitional crust during cratonization. The SPAN programs are important new data sets to clarify and in some cases solve outstanding problems in basin architecture and tectonic evolution.

Seasonal And Intra-seasonal Hydrological Responses To Change In Climate Pattern And Small Dams of the Faga Watershed In Burkina-Faso

NASA Astrophysics Data System (ADS)

Mamounata, K.

2015-12-01

In response to the increasing demand for food linked to the substantial growth of population in Burkina Faso, irrigation has been widely used by the farming community to support agricultural production. Thus a promising option for water resources development in such a context is to increase the number of small dams. It is assumed that the great number of small dams may have effect on sub-basins' hydrological dynamic. This study aims to assess the seasonal and the intra-seasonal change in river basins hydrology with the case study of the Faga River sub-basin located in Burkina-Faso, West Africa, using Water Simulation Model (WaSiM). For this watershed the number of small dams is slightly very important (More than 60) and their impact on the watershed runoff has been estimated simultaneously with the change in climate pattern. The coefficient of variation for rainfall in this sub-basin from 1982 to 2010 is 0.097 and the stream flow presents a seasonal average of 25.58Km3 per month for the same period. The intra-seasonal climate variation for the same period is estimated at 0.087 in the scenario where any dam has not been considered. Results based on simulation including the five important dams over the sub-basin show that the overall effect of small dams is on average a 20.76% in runoff. Projections using the Representative Concentration Pathways (RCP) 4.5 and 8.5 climate scenarios with increase of 25% of dams' number show a probable decrease of about 29.54% and 35.25% of the average during the next fifty years runoff. The study findings show that small dams reduce significantly the runoff from their watershed and the uncertainties related to the sustainability of the resource seems to be increasing during the same period. Therefore, despite the very large number of water storage infrastructures, reservoirs operating strategies have to be achieved for water sustainability within the Faga sub-basin.

A framework for human-hydrologic system model development integrating hydrology and water management: application to the Cutzamala water system in Mexico

NASA Astrophysics Data System (ADS)

Wi, S.; Freeman, S.; Brown, C.

2017-12-01

This study presents a general approach to developing computational models of human-hydrologic systems where human modification of hydrologic surface processes are significant or dominant. A river basin system is represented by a network of human-hydrologic response units (HHRUs) identified based on locations where river regulations happen (e.g., reservoir operation and diversions). Natural and human processes in HHRUs are simulated in a holistic framework that integrates component models representing rainfall-runoff, river routing, reservoir operation, flow diversion and water use processes. We illustrate the approach in a case study of the Cutzamala water system (CWS) in Mexico, a complex inter-basin water transfer system supplying the Mexico City Metropolitan Area (MCMA). The human-hydrologic system model for CWS (CUTZSIM) is evaluated in terms of streamflow and reservoir storages measured across the CWS and to water supplied for MCMA. The CUTZSIM improves the representation of hydrology and river-operation interaction and, in so doing, advances evaluation of system-wide water management consequences under altered climatic and demand regimes. The integrated modeling framework enables evaluation and simulation of model errors throughout the river basin, including errors in representation of the human component processes. Heretofore, model error evaluation, predictive error intervals and the resultant improved understanding have been limited to hydrologic processes. The general framework represents an initial step towards fuller understanding and prediction of the many and varied processes that determine the hydrologic fluxes and state variables in real river basins.

A large-scale simulation of climate change effects on flood regime - A case study for the Alabama-Coosa-Tallapoosa River Basin

NASA Astrophysics Data System (ADS)

Dullo, T. T.; Gangrade, S.; Marshall, R.; Islam, S. R.; Ghafoor, S. K.; Kao, S. C.; Kalyanapu, A. J.

2017-12-01

The damage and cost of flooding are continuously increasing due to climate change and variability, which compels the development and advance of global flood hazard models. However, due to computational expensiveness, evaluation of large-scale and high-resolution flood regime remains a challenge. The objective of this research is to use a coupled modeling framework that consists of a dynamically downscaled suite of eleven Coupled Model Intercomparison Project Phase 5 (CMIP5) climate models, a distributed hydrologic model called DHSVM, and a computational-efficient 2-dimensional hydraulic model called Flood2D-GPU to study the impacts of climate change on flood regime in the Alabama-Coosa-Tallapoosa (ACT) River Basin. Downscaled meteorologic forcings for 40 years in the historical period (1966-2005) and 40 years in the future period (2011-2050) were used as inputs to drive the calibrated DHSVM to generate annual maximum flood hydrographs. These flood hydrographs along with 30-m resolution digital elevation and estimated surface roughness were then used by Flood2D-GPU to estimate high-resolution flood depth, velocities, duration, and regime. Preliminary results for the Conasauga river basin (an upper subbasin within ACT) indicate that seven of the eleven climate projections show an average increase of 25 km2 in flooded area (between historic and future projections). Future work will focus on illustrating the effects of climate change on flood duration and area for the entire ACT basin.

Estimation of evapotranspiration in an arid region by remote sensing—A case study in the middle reaches of the Heihe River Basin

NASA Astrophysics Data System (ADS)

Li, Xingmin; Lu, Ling; Yang, Wenfeng; Cheng, Guodong

2012-07-01

Estimating surface evapotranspiration is extremely important for the study of water resources in arid regions. Data from the National Oceanic and Atmospheric Administration's Advanced Very High Resolution Radiometer (NOAA/AVHRR), meteorological observations and data obtained from the Watershed Allied Telemetry Experimental Research (WATER) project in 2008 are applied to the evaporative fraction model to estimate evapotranspiration over the Heihe River Basin. The calculation method for the parameters used in the model and the evapotranspiration estimation results are analyzed and evaluated. The results observed within the oasis and the banks of the river suggest that more evapotranspiration occurs in the inland river basin in the arid region from May to September. Evapotranspiration values for the oasis, where the land surface types and vegetations are highly variable, are relatively small and heterogeneous. In the Gobi desert and other deserts with little vegetation, evapotranspiration remains at its lowest level during this period. These results reinforce the conclusion that rational utilization of water resources in the oasis is essential to manage the water resources in the inland river basin. In the remote sensing-based evapotranspiration model, the accuracy of the parameter estimate directly affects the accuracy of the evapotranspiration results; more accurate parameter values yield more precise values for evapotranspiration. However, when using the evaporative fraction to estimate regional evapotranspiration, better calculation results can be achieved only if evaporative fraction is constant in the daytime.

Quantifying drag on wellbore casings in moving salt sheets

NASA Astrophysics Data System (ADS)

Weijermars, R.; Jackson, M. P. A.; Dooley, T. P.

2014-08-01

Frontier hydrocarbon development projects in the deepwater slopes of the Gulf of Mexico Basin, Santos Basin and Lower Congo Basin all require wells to cross ductile layers of autochthonous or allochthonous salt moving at peak rates of 100 mm yr-1. The Couette-Poiseuille number is introduced here to help pinpoint the depth of shear stress reversal in such salt layers. For any well-planned through salt, the probable range of creep forces of moving salt needs to be taken into account when designing safety margins and load-factor tolerance of the well casing. Drag forces increase with wellbore diameter, but more significantly with effective viscosity and speed of the creeping salt layer. The potential drag forces on cased wellbores in moving salt sheets are estimated analytically using a range of salt viscosities (1015-1019 Pa s) and creep rates (0-10 mm yr-1). Drag on perfectly rigid casing of infinite strength may reach up to 13 Giga Newton per meter wellbore length in salt having a viscosity of 1019 Pa s. Well designers may delay stress accumulations due to salt drag when flexible casing accommodates some of the early displacement and strain. However, all creeping salt could displace, fracture and disconnect well casing, eventually. The shear strength of typical heavy duty well casing (about 1000 MPa) can be reached due to drag by moving salt. Internal flow of salt will then fracture the casing near salt entry and exit points, but the structural damage is likely to remain unnoticed early in the well-life when the horizontal shift of the wellbore is still negligibly small (at less than 1 cm yr-1). Disruption of casing and production flow lines within the anticipated service lifetime of a well remains a significant risk factor within distinct zones of low-viscosity salt which may reach ultrafast creep rates of 100 mm yr-1.

[Integrated assessment of ecosystem quality of arid inland river basin based on RS and GIS: A case study on Shiyang River Basin, Northwest China].

PubMed

Liang, Bian Bian; Shi, Pei Ji; Wang, Wei; Tang, Xiao; Zhou, Wen Xia; Jing, Ye

2017-01-01

The Shiyang River Basin is an important ecological area of the Eastern Hexi Corridor, and is one of the most prominent areas of water conflict and ecological environment problems. An assessment of ecosystem quality in the Shiyang River Basin can provide a reference for ecological protection in arid inland basin. Based on the concept of ecosystem quality and the statistical yearbook, remotely sensed and land cover data, an evaluation index was established with consideration of three aspects of ecosystem (i.e., productivity, stability and bearing capacity). Kruskal-Wallis (Φ 2 ) test and entropy method were applied to determine the weights of evaluation index. With the assistance of RS, GIS and SPSS software, a comprehensive evaluation and change analysis of ecosystem quality and corresponding index were conducted for various ecosystem types in the Shiyang River Basin in 2000, 2005, 2010 and 2015. Results showed that the average ecosystem quality of the Shiyang River Basin was 57.76, and presented an obvious decrease with a magnitude of 0.72 per year du-ring 2000-2015. The spatial pattern of ecosystem quality was that the upstream was better than the midstream, and the midstream was superior to the downstream. The mean values of production capacity, stability and carrying capacity of ecosystem were 67.52, 45.37, and 58.53, respectively. Production capacity and stability had increased slightly, while carrying capacity gradually decreased. Considering various ecosystem types, the highest quality was detected for forest ecosystem with average annual value of 78.12, and this ecosystem presented the lowest decreasing magnitude of 0.28 per year; for grassland, farmland and urban ecosystems, the average annual value was 62.45, 58.76 and 50.29, respectively; the quality of wetland ecosystem was the lowest, and suffered the largest decline with an average rate of 0.98 per year.

Water Induced Hazard Mapping in Nepal: A Case Study of East Rapti River Basin

NASA Astrophysics Data System (ADS)

Neupane, N.

2010-12-01

This paper presents illustration on typical water induced hazard mapping of East Rapti River Basin under the DWIDP, GON. The basin covers an area of 2398 sq km. The methodology includes making of base map of water induced disaster in the basin. Landslide hazard maps were prepared by SINMAP approach. Debris flow hazard maps were prepared by considering geology, slope, and saturation. Flood hazard maps were prepared by using two approaches: HEC-RAS and Satellite Imagery Interpretation. The composite water-induced hazard maps were produced by compiling the hazards rendered by landslide, debris flow, and flood. The monsoon average rainfall in the basin is 1907 mm whereas maximum 24 hours precipitation is 456.8 mm. The peak discharge of the Rapati River in the year of 1993 at station was 1220 cu m/sec. This discharge nearly corresponds to the discharge of 100-year return period. The landslides, floods, and debris flows triggered by the heavy rain of July 1993 claimed 265 lives, affected 148516 people, and damaged 1500 houses in the basin. The field investigation and integrated GIS interpretation showed that the very high and high landslide hazard zones collectively cover 38.38% and debris flow hazard zone constitutes 6.58%. High flood hazard zone occupies 4.28% area of the watershed. Mitigation measures are recommendated according to Integrated Watershed Management Approach under which the non-structural and structural measures are proposed. The non-structural measures includes: disaster management training, formulation of evacuation system (arrangement of information plan about disaster), agriculture management practices, protection of water sources, slope protections and removal of excessive bed load from the river channel. Similarly, structural measures such as dike, spur, rehabilitation of existing preventive measures and river training at some locations are recommendated. The major factors that have contributed to induce high incidences of various types of mass movements and inundation in the basin are rock and soil properties, prolonged and high-intensity rainfall, steep topography and various anthropogenic factors.

Geochemical evolution of groundwater salinity at basin scale: a case study from Datong basin, Northern China.

PubMed

Wu, Ya; Wang, Yanxin

2014-05-01

A hydrogeochemical investigation using integrated methods of stable isotopes ((18)O, (2)H), (87)Sr/(86)Sr ratios, Cl/Br ratios, chloride-mass balance, mass balance and hydrogeochemical modeling was conducted to interpret the geochemical evolution of groundwater salinity in Datong basin, northern China. The δ(2)H, δ(18)O ratios in precipitation exhibited a local meteoric water line of δ(2)H = 6.4 δ(18)O -5 (R(2) = 0.94), while those in groundwater suggested their meteoric origin in a historically colder climatic regime with a speculated recharge rate of less than 20.5 mm overall per year, in addition to recharge from a component of deep residual ancient lake water enriched with Br. According to the Sr isotope binary mixing model, the mixing of recharges from the Shentou karst springs (24%), the western margins (11%) and the eastern margins (65%) accounts for the groundwater from the deep aquifers of the down-gradient parts in the central basin is a possible mixing mechanism. In Datong, hydrolysis of silicate minerals is the most important hydrogeochemical process responsible for groundwater chemistry, in addition to dissolution of carbonate and evaporites. In the recharge areas, silicate chemical weathering is typically at the bisiallitization stage, while that in the central basin is mostly at the monosiallitization stage with limited evidence of being in equilibrium with gibbsite. Na exchange with bound Ca, Mg prevails at basin scale, and intensifies with groundwater salinity, while Ca, Mg exchange with bound Na locally occurs in the east pluvial and alluvial plains. Although groundwater salinity increases with the progress of water-rock/sediment interactions along the flow path, as a result of carbonate solubility control and continuous evapotranspiration, Na-HCO3 and Na-Cl-SO4 types of water are usually characterized respectively in the deep and the shallow aquifers of an inland basin with a silicate terrain in an arid climatic regime.

Integrated Risk Index of Chemical Aquatic Pollution (IRICAP): case studies in Iberian rivers.

PubMed

Fàbrega, Francesc; Marquès, Montse; Ginebreda, Antoni; Kuzmanovic, Maja; Barceló, Damià; Schuhmacher, Marta; Domingo, José L; Nadal, Martí

2013-12-15

The hazard of chemical compounds can be prioritized according to their PBT (persistence, bioaccumulation, toxicity) properties by using Self-Organizing Maps (SOM). The objective of the present study was to develop an Integrated Risk Index of Chemical Aquatic Pollution (IRICAP), useful to evaluate the risk associated to the exposure of chemical mixtures contained in river waters. Four Spanish river basins were considered as case-studies: Llobregat, Ebro, Jucar and Guadalquivir. A SOM-based hazard index (HI) was estimated for 205 organic compounds. IRICAP was calculated as the product of the HI by the concentration of each pollutant, and the results of all substances were aggregated. Finally, Pareto distribution was applied to the ranked lists of compounds in each site to prioritize those chemicals with the most significant incidence on the IRICAP. According to the HI outcomes, perfluoroalkyl substances, as well as specific illicit drugs and UV filters, were among the most hazardous compounds. Xylazine was identified as one of the chemicals with the highest contribution to the total IRICAP value in the different river basins, together with other pharmaceutical products such as loratadine and azaperol. These organic compounds should be proposed as target chemicals in the implementation of monitoring programs by regulatory organizations. Copyright © 2013 Elsevier B.V. All rights reserved.

Institutional arrangements for beneficial regional cooperation on water, energy and food priority issues in the Eastern Nile Basin

NASA Astrophysics Data System (ADS)

Al-Saidi, Mohammad; Hefny, Amr

2018-07-01

Research on water cooperation in the Eastern Nile Basin has focused on expanding policy and diplomacy tools for a better allocation of transboundary water resources confined to the river. Regional cooperation on water and related sectors such as energy and land expands the bargaining and areas for mutual gain, and thus enhances cooperation perspectives. This paper looks at the contribution and the potential benefits of a regional cooperation approach to addressing the underlying challenges of water diplomacy, such as complexity and distrust. It also promotes the understanding of river basins as a "resource basin" of integrated and linked resource-use issues, not always related to the river flow. The paper provides an analysis of priority issues for water-energy-food nexus in regional cooperation in the Eastern Nile Basin. This basin represents an illustrative case for regional cooperation and increased integration due to multiple comparative advantages inherent in the uneven endowments of water, energy and arable land resources, and to varying levels of economic and technological advancement among the three riparian countries: Egypt, Sudan and Ethiopia. The paper also analyzes institutional arrangements on a regional scale, and elaborates on the inherent trade-offs associated with them.

Geometry and structure of the pull-apart basins developed along the western South American-Scotia plate boundary (SW Atlantic Ocean)

NASA Astrophysics Data System (ADS)

Esteban, F. D.; Tassone, A.; Isola, J. I.; Lodolo, E.; Menichetti, M.

2018-04-01

The South American-Scotia plate boundary is a left-lateral fault system which runs roughly E-W for more than 3000 km across the SW Atlantic Ocean and the Tierra del Fuego Island, reaching to the west the southern Chile Trench. Analyses of a large dataset of single- and multi-channel seismic reflection profiles acquired offshore has allowed to map the trace of the plate boundary from Tierra del Fuego to the Malvinas Trough, a tectonic depression located in the eastern part of the fault system, and to reconstruct the shape and geometry of the basins formed along the principal displacement zone of the fault system. Three main Neogene pull-apart basins that range from 70 to 100 km in length, and from 12 to 22 km in width, have been identified along this segment of the plate boundary. These basins have elongated shapes with their major axes parallel to the ENE-WSW direction of the fault zone. The sedimentary architecture and the infill geometry of the basins suggest that they represent mostly strike-slip dominated transtension basins which propagated from E to W. The basins imaged by seismic data show in some cases geometrical and structural features linked to the possible reactivation of previous wedge-top basins and inherited structures pertaining to the external front of the Magallanes fold-and-thrust compression belt, along which the South American-Scotia fault system has been superimposed. It is suggested that the sequence of the elongated basins occur symmetrically to a thorough going strike-slip fault, in a left-stepping geometrical arrangement, in a manner similar to those basins seen in other transcurrent environments.

Occurrence, Distribution, Instantaneous Loads, and Yields of Dissolved Pesticides in the San Joaquin River Basin, California, During Summer Conditions, 1994 and 2001

USGS Publications Warehouse

Brown, Larry R.; Panshin, Sandra Y.; Kratzer, Charles R.; Zamora, Celia; Gronberg, JoAnn M.

2004-01-01

Water samples were collected from 22 drainage basins for analysis of 48 dissolved pesticides during summer flow conditions in 1994 and 2001. Of the 48 pesticides, 31 were reported applied in the basin in the 28 days preceding the June 1994 sampling, 25 in the 28 days preceding the June 2001 sampling, and 24 in the 28 days preceding the August 2001 sampling. The number of dissolved pesticides detected was similar among sampling periods: 26 were detected in June 1994, 28 in June 2001, and 27 in August 2001. Concentrations of chlorpyrifos exceeded the California criterion for the protection of aquatic life from acute exposure at six sites in June 1994 and at five sites in June 2001. There was a single exceedance of the criterion for diazinon in June 1994. The number of pesticides applied in tributary basins was highly correlated with basin area during each sampling period (Spearman's r = 0.85, 0.70, and 0.84 in June 1994, June 2001, and August 2001, respectively, and p < 0.01 in all cases). Larger areas likely include a wider variety of crops, resulting in more varied pesticide use. Jaccard's similarities, cluster analysis, principal components analysis, and instantaneous load calculations generally indicate that west-side tributary basins were different from east-side tributary basins. In general, west-side basins had higher concentrations, instantaneous loads, and instantaneous yields of dissolved pesticides than east-side basins, although there were a number of exceptions. These differences may be related to a number of factors, including differences in basin size, soil texture, land use, irrigation practices, and stream discharge.

Cost effectiveness of conventional versus LANDSAT use data for hydrologic modeling

NASA Technical Reports Server (NTRS)

George, T. S.; Taylor, R. S.

1982-01-01

Six case studies were analyzed to investigate the cost effectiveness of using land use data obtained from LANDSAT as opposed to conventionally obtained data. A procedure was developed to determine the relative effectiveness of the two alternative means of acquiring data for hydrological modelling. The cost of conventionally acquired data ranged between $3,000 and $16,000 for the six test basins. Information based on LANDSAT imagery cost between $2,000 and $5,000. Results of the effectiveness analysis shows the differences between the two methods are insignificant. From the cost comparison and the act that each method, conventional and LANDSAT, is shown to be equally effective in developing land use data for hydrologic studies, the cost effectiveness of the conventional or LANDSAT method is found to be a function of basin size for the six test watersheds analyzed. The LANDSAT approach is cost effective for areas containing more than 10 square miles.

Analysis of Infrequent (Quasi-Decadal) Large Groundwater Recharge Events: A Case Study for Northern Utah, United States

NASA Astrophysics Data System (ADS)

Masbruch, M.; Rumsey, C.; Gangopadhyay, S.; Susong, D.; Pruitt, T.

2015-12-01

There has been a considerable amount of research linking climatic variability to hydrologic responses in arid and semi-arid regions such as the western United States. Although much effort has been spent to assess and predict changes in surface-water resources, little has been done to understand how climatic events and changes affect groundwater resources. This study focuses on quantifying the effects of large quasi-decadal groundwater recharge events on groundwater in the northern Utah portion of the Great Basin for the period 1960 to 2013. Groundwater-level monitoring data were analyzed with climatic data to characterize climatic conditions and frequency of these large recharge events. Using observed water-level changes and multivariate analysis, five large groundwater recharge events were identified within the study area and period, with a frequency of about 11 to 13 years. These events were generally characterized as having above-average annual precipitation and snow water equivalent and below-average seasonal temperatures, especially during the spring (April through June). Existing groundwater flow models for several basins within the study area were used to quantify changes in groundwater storage from these events. Simulated groundwater storage increases per basin from a single event ranged from about 115 Mm3 (93,000 acre-feet) to 205 Mm3 (166,000 acre-ft). Extrapolating these amounts over the entire northern Great Basin indicates that even a single large quasi-decadal recharge event could result in billions of cubic meters (millions of acre-feet) of groundwater recharge. Understanding the role of these large quasi-decadal recharge events in replenishing aquifers and sustaining water supplies is crucial for making informed water management decisions.

On the intensity and type transition of land use at the basin scale using RS/GIS: a case study of the Hanjiang River Basin.

PubMed

Yu, Guangming; Zeng, Qun; Yang, Shan; Hu, Limei; Lin, Xiaowei; Che, Yi; Zheng, Yuge

2010-01-01

The purpose of this study is to investigate the land use intensity and land use change type at the basin scale in the middle and lower reaches of the Hanjiang River Basin (in Hubei Province, China) by combining the Landsat TM images in 1995 and 2000 with the land use database (in scale 1:10,000) and relative data. In this study, the basic data is acquired from the interpretation of remote sensing (RS) images. The intensity of land use and the rate of change in double-directions of land use dynamics are calculated with the support of software ARC/INFO. The intensity of land use is indicated by the intensity coefficient of land use, and the transition of land use types is quantified as the rate of change in double-direction of land use types and also expressed as the transition matrix of land use types. The results are expressed in space by Geographic Information System (GIS) software. Results of this study show that (1) the intensity of land use is high in the study region, the intensity coefficients of land use in 1995 and 2000 are 260.025 and 290.526, respectively, and the intensity of development and utilization of land is trend to increscent; and (2) the rate of land use change in double directions in the whole study region is 0.52 with great spatial variation and the differentiation of land use types. In the differentiation of land use types, the unutilized land (with the rate to 4.391) is developed fast, the grassland (with 2.836) and water area (with 1.664) are disturbed severely, and these changes will influence the eco-environment in the Hanjiang River Basin and all the Yangtze Basin. The rates of the farmland and the woodland are 0.424 and 0.344, respectively, meaning that the fundamentals of regional human-environmental system are relative stable. With this study, we can conclude that (1) the patterns of land use are increasingly changing in the study region, the environmental impacts are escalated on this stage, and the further outcomes are destined to change the stability of the regional human-environmental system; and (2) the most useful method to study the present land use and its change is through the use of the RS/GIS with the land use database (in scale 1:10,000).

Lunar impact basins: New data for the western limb and far side (Orientale and South Pole-Aitken basins) from the first Galileo flyby

NASA Astrophysics Data System (ADS)

Head, James W.; Murchie, Scott; Mustard, John F.; Pieters, Carle M.; Neukum, Gerhard; McEwen, Alfred; Greeley, Ronald; Nagel, Engelbert; Belton, Michael J. S.

1993-09-01

Compositional aspects of impact basin materials can be analyzed using multispectral image data acquired by the Galileo solid state imaging (SSI) experiment during the December 1990 lunar encounter. These data provide important information on the spectral properties of the western lunar limb and parts of the far side. The SSI images cover the wavelength range 0.4-1.0 μm, allowing measurement of spectral slope and estimation of the strength of the 1 μm absorption due to iron in the mafic minerals olivine and pyroxene. Among deposits of the 930-km-diameter Orientale basin, exterior ejecta comprising the Hevelius Formation is relatively homogeneous and spectrally similar to mature Apollo 16 soils, suggesting an upper crustal source. The centrally located Maunder Formation is distinct from the younger mare basalts but comparable to the Hevelius Formation in its spectral reflectance properties, supporting an interpretation as basin impact melt. The Montes Rook Formation, located in an annulus between the Maunder and the Hevelius, shows a slightly stronger mafic absorption and may be the deepest crustal material excavated. The distal Orientale deposits show local mafic enhancements (in the Schiller-Schickard and Mendel-Rydberg regions) interpreted to represent pre-Orientale mare deposits, or cryptomaria, intermixed with overlying basin ejecta. In this case, maria of sizes comparable to those presently observed were widespread in this region before the Orientale impact. Mixing-model analyses are consistent with the ballistic erosion and sedimentation model for ejecta emplacement in the distal regions beyond the continuous ejecta deposit. On the southern lunar farside, a high area with an enhanced mafic absorption corresponds to the interior and rim of the pre-Nectarian South Pole-Aitken impact basin, 2000-2500 km in diameter. The anomaly is interpreted to be due to several factors, including excavation into the more mafic lower crust, and the presence of extensive early volcanic fill (cryptomare), similar to that seen in ancient basins such as Smythii and Australe. These results show that although basin-forming events are an important factor in producing lateral heterogeneities in crustal composition, and in modifying preexisting deposits (such as cryptomaria), the majority of material in even the largest basins was excavated from mixed crustal layer of anorthosite, basin ejecta, and cryptomaria deposits (generally corresponding to the megaregolith), an upper crustal layer of anorthosite, and a lower more noritic layer. Many of the basic questions remaining from this study could be addressed by global high-resolution geochemical and mineralogical data obtained by polar orbiting spacecraft.

Tectonics vs. Climate efficiency in triggering detrital input in sedimentary basins: the Po Plain-Venetian-Adriatic Foreland Basin (Northern Italy)

NASA Astrophysics Data System (ADS)

Amadori, Chiara; Di Giulio, Andrea; Toscani, Giovanni; Lombardi, Stefano; Milanesi, Riccardo; Panara, Yuri; Fantoni, Roberto

2017-04-01

The relative efficiency of tectonics respect to climate in triggering erosion of mountain belts is a classical but still open debate in geosciences. The fact that data both from tectonically active and inactive mountain regions in different latitudes, record a worldwide increase of sediment input to sedimentary basins during the last million years concomitantly with the cooling of global climate and its evolution toward the modern high amplitude oscillating conditions pushed some authors to conclude that Pliocene-Pleistocene climate has been more efficient than tectonics in triggering mountain erosion. Po Plain-Venetian-Adriatic Foreland System, made by the relatively independent Po Plain-Northern Adriatic Basin and Venetian-Friulian Basin, provides an ideal case of study to test this hypothesis and possibly quantify the difference between the efficiency of the two. In fact it is a relatively closed basin (i.e. without significant sediment escape) with a fairly continuous sedimentation (i.e. with a quite continuous sedimentary record) completely surrounded by collisional belts (Alps, Northern Apennines and Dinarides) that experienced only very weak tectonic activity since Calabrian time, i.e. when climate cooling and cyclicity increased the most. We present a quantitative reconstruction of the sediment flow delivered from the surrounding mountain belts to the different part of the basin during Pliocene-Pleistocene time. This flow was obtained through the 3D reconstruction of the Venetian-Friulian and Po Plain Northern Adriatic Basins architecture, performed by means of the seismic-based interpretation and time-to-depth conversion of six chronologically constrained surfaces (seismic and well log data from courtesy of ENI); moreover, a 3D decompaction of the sediment volume bounded by each couple of surfaces has been included in the workflow, in order to avoid compaction-related bias. The obtained results show in both Basins a rapid four-folds increase of the sediment input occurred since mid-Pleistocene time respect to Pliocene-Gelasian times. Even if the absolute amount of sediment arriving in the two basins is quite different, reflecting the different extension of their source regions, this increase occurred concomitantly with both the strong decrease of tectonic activity in the surrounding belts and the onset of major glaciations in the Alpine range. Therefore we argue that a cool, highly oscillating climate, causing glacial-interglacial cycles is approximately 4 times more efficient than tectonics in promoting the erosion of mountain belts and the related detrital input in the surrounding sedimentary basins.

An integrated framework to assess adaptation options to climate change impacts in an irrigated basin in Central North Chile

NASA Astrophysics Data System (ADS)

Vicuna, S.; Melo, O.; Meza, F. J.; Alvarez, P.; Maureira, F.; Sanchez, A.; Tapia, A.; Cortes, M.; Dale, L. L.

2013-12-01

Future climate conditions could potentially affect water supply and demand on water basins throughout the world but especially on snowmelt-driven agriculture oriented basins that can be found throughout central Chile. Increasing temperature and reducing precipitation will affect both the magnitude and timing of water supply this part of the world. Different adaptation strategies could be implemented to reduce the impacts of such scenarios. Some could be incorporated as planned policies decided at the basin or Water Use Organization levels. Examples include changing large scale irrigation infrastructure (reservoirs and main channels) either physically or its operation. Complementing these strategies it is reasonable to think that at a disaggregated level, farmers would also react (adapt) to these new conditions using a mix of options to either modify their patterns of consumption (irrigation efficiency, crop mix, crop area reduction), increase their ability to access new sources of water (groundwater, water markets) or finally compensate their expected losses (insurance). We present a modeling framework developed to represent these issues using as a case study the Limarí basin located in Central Chile. This basin is a renowned example of how the development of reservoirs and irrigation infrastructure can reduce climate vulnerabilities allowing the economic development of a basin. Farmers in this basin tackle climate variability by adopting different strategies that depend first on the reservoir water volume allocation rule, on the type and size of investment they have at their farms and finally their potential access to water markets and other water supplies options. The framework developed can be used to study these strategies under current and future climate scenarios. The cornerstone of the framework is an hydrology and water resources model developed on the WEAP platform. This model is able to reproduce the large scale hydrologic features of the basin such as snowmelt hydrology, reservoir operation and groundwater dynamics. Crop yield under different water irrigation patterns have been inferred using a calibrated Cropsyst model. These crop yields together with user association irrigation constraints are used in a GAMS optimization model embedded dynamically in WEAP in order to obtain every year decisions on crop mix (including fallow land), irrigation patterns and participation in the spot water market. The GAMS optimization model has been calibrated using annual crop mix time series derived using a combination of sources of information ranging from different type of census plus satellite images. The resulting modeling platform is able to simulate under historic and future climate scenarios water availability in different locations of the basin with associated crop yield and economic consequences. The platform also allows the implementation of autonomous and planned adaptation strategies that could reduce the impacts of climate variability and climate change.

Using the analytical hierarchy process to assess the environmental vulnerabilities of basins in Taiwan.

PubMed

Chang, Chia-Ling; Chao, Yu-Chi

2012-05-01

Every year, Taiwan endures typhoons and earthquakes; these natural hazards often induce landslides and debris flows. Therefore, watershed management strategies must consider the environmental vulnerabilities of local basins. Because many factors affect basin ecosystems, this study applied multiple criteria analysis and the analytical hierarchy process (AHP) to evaluate seven criteria in three phases (geographic phase, hydrologic phase, and societal phase). This study focused on five major basins in Taiwan: the Tan-Shui River Basin, the Ta-Chia River Basin, the Cho-Shui River Basin, the Tseng-Wen River Basin, and the Kao-Ping River Basin. The objectives were a comprehensive examination of the environmental characteristics of these basins and a comprehensive assessment of their environmental vulnerabilities. The results of a survey and AHP analysis showed that landslide area is the most important factor for basin environmental vulnerability. Of all these basins, the Cho-Shui River Basin in central Taiwan has the greatest environmental vulnerability.

Streambed adjustment and channel widening in eastern Nebraska

USGS Publications Warehouse

Rus, David L.; Dietsch, Benjamin J.; Simon, Andrew

2003-01-01

In eastern Nebraska, stream straightening and dredging efforts since the 1890s have disturbed the natural equilibrium of stream channels and have led to streambed adjustment by degradation and subsequent channel widening. This report describes a study to evaluate the effect these disturbances have had on stream channels in eastern Nebraska. Two sets of survey data were collected approximately 2 years apart during 1996-99 at 151 primary sites. Additionally, historical streambed-elevation data (dating back to the 1890s) were compiled from several sources for the primary sites and 45 supplemental sites, and relevant disturbances were identified for each of eight basin groupings. Streambed-elevation data sets were used to estimate the amount of change to the streambed at the sites over the time period of the data. Recent channel widening was documented for 73 of the primary sites by comparing the two survey sets. The majority of observed streambed-gradation responses appear to be related to the various straightening efforts and to the effects of grade-control structures in the study area. Channel responses were complicated by the presence of multiple disturbances. However, in many cases, the streambed-elevation data sets provide a reliable representation of the past streambed gradation, with some sites showing 6 to 7 meters of degradation since they were straightened. Many sites that had been straightened showed considerable degradation following the disturbance. This indicates that eastern Nebraska stream channels can regain equilibrium mainly through the slope adjustment process of head-ward-progressing degradation. Bank failures were documented at sites in all eight of the basin groupings analyzed, and widening rates were computed at 64 of 73 sites. Observed bank widening in the Big Blue River Basin, a relatively unstraightened basin, indicates that other disturbances besides stream-channel straightening may be causing channel responses in the basin and possibly in the entire study area.

The assessment of land use change impact on watersheds runoff using SWAT: case study of Urmia Lake in Iran

NASA Astrophysics Data System (ADS)

Jabbari, Anahita; Jarihani, Ben; Rezaie, Hossein

2015-04-01

Lake Urmia, long counted among the world's largest saltwater lakes, contains only 5% of the amount of water it did just 20 years ago. The decline is generally blamed on a combination of drought, increased water diversion for irrigated agriculture within the lake's watershed and land use mismanagement. It has been believed that land use changes in Lake Urmia basin is one of the most important factors in shrinkage of Urmia Lake in recent decades. Transforming the traditional agricultural practices (i.e., wheat) to the more water consuming practices (i.e., apple orchards) is one of the most important reasons increased agricultural water consumption in the watershed. In this study we assessed the effect of the land use changes of watershed in hydrological runoff processing in the Nazloo chai watershed, one of the most important river basins of the Urmia Lake basin. Actually the rapid and at the same time unreasonable transformations of land use in farm lands of Urmia lake sub basins, extremely has been raised the amount of blue water (surface or groundwater) consumption in watershed which leads to dramatic decrement of watershed runoff amounts. One of the most unfavorable consequences of land use change was changing the blue and green (rainwater insofar as it does not become runoff) water usage patterns in watershed, in addition to water use increment. The soil and water assessment tool (SWAT), one of the most important and reliable models which was used to model the rainfall runoff, has been used in current study. The land use maps were extracted from Landsat images archives for the most severe turning points in respect of land use change in the recent 30 years. After calibrating the model, several land use patterns of historical data were used in the model to produce the runoff. The results showed the strong relation between land use change and runoff reduction in the Lake Urmia basin.

Report of the Workshop on Geologic Applications of Remote Sensing to the Study of Sedimentary Basins

NASA Technical Reports Server (NTRS)

Lang, H. R. (Editor)

1985-01-01

The Workshop on Geologic Applications of Remote Sensing to the Study of Sedimentary Basins, held January 10 to 11, 1985 in Lakewood, Colorado, involved 43 geologists from industry, government, and academia. Disciplines represented ranged from vertebrate paleontology to geophysical modeling of continents. Deliberations focused on geologic problems related to the formation, stratigraphy, structure, and evolution of foreland basins in general, and to the Wind River/Bighorn Basin area of Wyoming in particular. Geological problems in the Wind River/Bighorn basin area that should be studied using state-of-the-art remote sensing methods were identified. These include: (1) establishing the stratigraphic sequence and mapping, correlating, and analyzing lithofacies of basin-filling strata in order to refine the chronology of basin sedimentation, and (2) mapping volcanic units, fracture patterns in basement rocks, and Tertiary-Holocene landforms in searches for surface manifestations of concealed structures in order to refine models of basin tectonics. Conventional geologic, topographic, geophysical, and borehole data should be utilized in these studies. Remote sensing methods developed in the Wind River/Bighorn Basin area should be applied in other basins.

Quantification of site-city interaction effects on the response of structure under double resonance condition

NASA Astrophysics Data System (ADS)

Kumar, Neeraj; Narayan, Jay Prakash

2018-01-01

This paper presents the site-city interaction (SCI) effects on the response of closely spaced structures under double resonance condition (F_{02{{D}}}^{{S}} = F_{02{{D}}}^{{B}}), where F_{02{{D}}}^{{S}} and F_{02{{D}}}^{{B}} are fundamental frequencies of 2-D structure and 2-D basin, respectively. This paper also presents the development of empirical relations to predict the F_{02{{D}}}^{{B}} of elliptical and trapezoidal basins for both the polarizations of the S wave. Simulated results revealed that F_{02{{D}}}^{{B}} of a 2-D basin very much depends on its geometry, shape ratio and polarization of the incident S wave. The obtained spectral amplification factor (SAF) at F_{02{{D}}}^{{S}} of a standalone structure in a 2-D basin is greater than that in the 1-D case under double resonance condition. A considerable reduction of the fundamental resonance frequency of structures due to the SCI effects is observed for both the polarizations of the S wave. The SAFs at F_{02{{D}}}^{{S}} of closely spaced structures due to SCI effects is larger in the case of SV than SH waves. A splitting of the fundamental-mode frequency bandwidth along with the drastic decrease of SAF due to the SCI effects is obtained. The findings of this paper raise the question concerning the validity of the predicted response of standalone structure based on soil-structure interaction for the design of structures in a 2-D small basin, in an urban environment.

How reframing a water management issue across scales and levels impacts on perceptions of justice and injustice

NASA Astrophysics Data System (ADS)

Patrick, M. J.; Syme, G. J.; Horwitz, P.

2014-11-01

Social justice is a key outcome of water allocation, management and governance. It is commonly expressed in water policies and strategies in terms of achieving equitable distribution of water resources. In complex multi-level systems just and unjust outcomes can result from the same water allocation decision. In some cases a just outcome at one level may cause an injustice at another level for the same or a different set of stakeholders. The manner in which a water management issue is framed and reframed across different levels within a system influences stakeholder perceptions of whether a water allocation decision is just or unjust, which in turn influences the successful adoption and implementation of such a decision. This paper utilises a case study from the Murray-Darling Basin in Australia to illustrate how reframing a water management issue across multiple scales and levels can help understand stakeholders' perceptions of justice and injustice. In this case study two scales are explored, an institutional and an organisational scale; each comprising levels at the federal, basin, state and region. The water management issue of domestic and stock dams was tracked through the various scales and levels and illustrated how reframing an issue at different levels can influence the analysis of just or equitable outcomes. The case study highlights the need to treat justice in water allocation as an ever evolving problem of the behaviour of a social system rather than the meeting of static principles of what is 'right'. This points to the importance of being attentive to the dynamic and dialogical nature of justice when dealing with water allocation issues across scales and levels of water governance.

Numerical modeling of severe convective storms occurring in the Carpathian Basin

NASA Astrophysics Data System (ADS)

Horváth, Á.; Geresdi, I.; Németh, P.; Csirmaz, K.; Dombai, F.

Squall lines often cause serious damages due to the strong surface outflow, hail, or heavy precipitation in Hungary every summer. Squall lines in the Carpathian Basin can be classified into two main categories: pre-frontal squall-lines and frontal convective lines. In this paper, these two types of severe mesoscale phenomena are investigated using the high resolution numerical weather prediction model, the MM5. The case study for the first type of convective systems occurred on 18th May 2005 when two main convective lines with their embedded severe storms formed daytime and caused high-velocity wind events and extensive damages in the eastern part of Hungary. The second case study is a frontal squall line that hit Budapest on 20th August 2006 and the associated high precipitation (HP) supercells reached the capital of Hungary at same time when the traditional Constitution Day firework began. The consequences were catastrophic: five people were killed and more than one thousand were injured due to the extreme weather. The non-hydrostatic high resolution MM5 model was able to simulate and catch the severe weather events occurred on the days under discussion. Moreover, the model was able to compute the detailed structure of the supercells embedded in thunderstorm lines. By studying the equivalent potential temperature (EPT) fields at lower levels, we state that in the prefrontal case, there is a competition between the supercell thunderstorms for the wet and warm air. A thunderstorm that can collect the wet and warm air from larger area will have longer lifetime and more intense updraft. In the second case, the frontal squall lines, the movement and the behavior of the supercell storms embedded in the line was highly determined by the synoptic-scale motions and less affected by the EPT field of the prefrontal masses.

THE DRAINAGE EFFICIENCY INDEX (DEI) AS AN MORPHOLOGIAL INDICATOR OF LANDSLIDE SPATIAL OCCURRENCE IN MOUNTAINOUS CATCHMENTS. A case of study applied in the mountainous region of Brazilian Southeastern.

NASA Astrophysics Data System (ADS)

Henrique Muniz Lima, Pedro; Luiza Coelho Netto, Ana; do Couto Fernandes, Manoel

2016-04-01

Morphometric parameters, acquired notoriety mainly after the Drainage Density proposition (Horton 1932, 1945) and after they were applied by geomorphologists on the perspective to understand landscape functionalities, quantifying their characteristics through parameters and indexes. After the drainage density, many other parameters which describe the basin characteristics, behavior and dynamics have been proposed. Among them, for example, the DEI was proposed by Coelho Netto and contributors during the 80's, while they were seek to understand the hydrological and erosive dynamics on Bananal river basin (Brazilian Southeastern). Through this investigations the DEI was created, revealing the importance of parameters as hollow and drainage density, conjugated to the topographic gradient (Meis et al. 1982) who prosecute controls on the water flow efficiency along the hollows in order to activate the regressive erosion of the main channel. Later on this index was applied on the basin scale in several works developed in mountainous regions, showing a remarkable correlation with the occurrence of landslides such as showed by Coelho Netto et al. (2007); that posteriorly use this index as one of the components of the landslide susceptibility map for the Tijuca Massif, located in Rio de Janeiro Municipality. This work aims to establish patterns of the DEI index values (applied to mountainous low order basins) and the relationship on the occurrence of Debriflows or shallow translational slides. For this, the DEI index was applied on 4 different study areas located on the Southeastern mountainous region of Brazil to address deeply the connection between the index and the occurrence of landslides of different types applied for first and second order basins. The major study area is the Córrego Dantas Basin, situated in Nova Friburgo municipality (RJ), which is a 53 km² basin was affected by 327 landslides caused by a heavy rainfall on January 2011; Coelho Netto et al. (in press). The other selected areas were also affected by landslides and were selected to enrich the sampling and turn the analysis more reliable and complete. Briefly regarding the results, it was found a heavy relationship between the Debris flows occurrence and basin with high values of DEI and also a good relationship between shallow landslides and low values of DEI index, as expected. This relation can be briefly explained through one of the initial believes that expect on basin with a high drainage potential, consequently high values of DEI, are more prone to happen landslides as Debriflows enhancing regressive erosion of the main channel and their development on the headward direction. While basin with low drainage potential, consequently lower values of DEI are more prone to happen landslides as shallow translational that are movements more related to the particular slope properties. Finally we believe that the proposed index can be a good predictor of landslide occurrence (on their different types) when applied to lower order basin. Supplementary analysis are intend to be showed during the presentation during the European Geosciences Union General Assembly 2016.

How large is the Upper Indus Basin? The pitfalls of auto-delineation using DEMs

NASA Astrophysics Data System (ADS)

Khan, Asif; Richards, Keith S.; Parker, Geoffrey T.; McRobie, Allan; Mukhopadhyay, Biswajit

2014-02-01

Extraction of watershed areas from Digital Elevation Models (DEMs) is increasingly required in a variety of environmental analyses. It is facilitated by the availability of DEMs based on remotely sensed data, and by Geographical Information System (GIS) software. However, accurate delineation depends on the quality of the DEM and the methodology adopted. This paper considers automated and supervised delineation in a case study of the Upper Indus Basin (UIB), Pakistan, for which published estimates of the basin area show significant disagreement, ranging from 166,000 to 266,000 km2. Automated delineation used ArcGIS Archydro and hydrology tools applied to three good quality DEMs (two from SRTM data with 90m resolution, and one from 30m resolution ASTER data). Automatic delineation defined a basin area of c.440,000 km2 for the UIB, but included a large area of internal drainage in the western Tibetan Plateau. It is shown that discrepancies between different estimates reflect differences in the initial extent of the DEM used for watershed delineation, and the unchecked effect of iterative pit-filling of the DEM (going beyond the filling of erroneous pixels to filling entire closed basins). For the UIB we have identified critical points where spurious addition of catchment area has arisen, and use Google Earth to examine the geomorphology adjacent to these points, and also examine the basin boundary data provided by the HydroSHEDS database. We show that the Pangong Tso watershed and some other areas in the western Tibetan plateau are not part of the UIB, but are areas of internal drainage. Our best estimate of the area of the Upper Indus Basin (at Besham Qila) is 164,867 km2 based on the SRTM DEM, and 164,853 km2 using the ASTER DEM). This matches the catchment area measured by WAPDA SWHP. An important lesson from this investigation is that one should not rely on automated delineation, as iterative pit-filling can produce spurious drainage networks and basins, when there are areas of internal drainage nearby.

Web-Based Water Accounting Scenario Platform to Address Uncertainties in Water Resources Management in the Mekong : A Case Study in Ca River Basin, Vietnam

NASA Astrophysics Data System (ADS)

Apirumanekul, C.; Purkey, D. R.; Pudashine, J.; Seifollahi-Aghmiuni, S.; Wang, D.; Ate, P.; Meechaiya, C.

2017-12-01

Rapid economic development in the Mekong Region is placing pressure on environmental resources. Uncertain changes in land-use, increasing urbanization, infrastructure development, migration patterns and climate risks s combined with scarce water resources are increasing water demand in various sectors. More appropriate policies, strategies and planning for sustainable water resource management are urgently needed. Over the last five years, Vietnam has experienced more frequent and intense droughts affecting agricultural and domestic water use during the dry season. The Ca River Basin is the third largest river basin in Vietnam with 35% of its area located in Lao PDR. The delta landscape comprises natural vegetation, forest, paddy fields, farming and urban areas. The Ca River Basin is experiencing ongoing water scarcity that impacts on crop production, farming livelihoods and household water consumption. Water scarcity is exacerbated by uncertainties in policy changes (e.g. changes in land-use, crop types), basin development (e.g. reservoir construction, urban expansion), and climate change (e.g. changes in rainfall patterns and onset of monsoon). The Water Evaluation And Planning (WEAP) model, with inputs from satellite-based information and institutional data, is used to estimate water supply, water use and water allocation in various sectors (e.g. household, crops, irrigation and flood control) under a wide range of plausible future scenarios in the Ca River Basin. Web-Based Water Allocation Scenario Platform is an online implementation of WEAP model structured in terms of a gaming experience. The online game, as an educational tool, helps key agencies relevant to water resources management understand and explore the complexity of integrated system of river basin under a wide range of scenarios. Performance of the different water resources strategies in Ca River Basin (e.g. change of dam operation to address needs in various sectors, construction of dams, changes in cropping patterns and increasing irrigation diversion) under a wide range of uncertainties will be assessed. The game allows stakeholders to participate in a realistic game that requires them to make choices amongst various water management strategies with the goal of improving water management towards greater sustainability.

Ground and satellite based assessment of meteorological droughts: The Coello river basin case study

NASA Astrophysics Data System (ADS)

Cruz-Roa, A. F.; Olaya-Marín, E. J.; Barrios, M. I.

2017-10-01

The spatial distribution of droughts is a key factor for designing water management policies at basin scale in arid and semi-arid regions. Ground hydro-meteorological data in neo-tropical areas are scarce; therefore, the merging of ground and satellite datasets is a promissory approach for improving our understanding of water distribution. This paper compares three monthly rainfall interpolation methods for drought evaluation. The ordinary kriging technique based on ground data, and cokriging with elevation as auxiliary variable were compared against cokriging using the Tropical Rainfall Measuring Mission (TRMM) Multi-Satellite Precipitation Analysis (TMPA). Twenty rain gauge stations and the 3B42V7 version of the TMPA research dataset were considered. Comparisons were made over the Coello river basin (Colombia) at 3″ spatial resolution covering a period of eight years (1998-2005). The best spatial rainfall estimation was found for cokriging using ground data and elevation. The spatial support of TMPA dataset is very coarse for a merged interpolation with ground data, this spatial scales discrepancy highlight the need to consider scaling rules in the interpolation process.

Vegetation Response to Changing Climate - A Case Study from Gandaki River Basin in Nepal Himalaya

NASA Astrophysics Data System (ADS)

Panthi, J., Sr.; Kirat, N. H.; Dahal, P.

2015-12-01

The climate of the Himalayan region is changing rapidly - temperature is increasingly high and rainfall has become unpredictable. IPCC predicts that average annual mean temperature over the Asian land mass, including the Himalayas, will increase by about 3°C by the 2050s and about 5°C by the 2080s and the average annual precipitation in this region will increase by 10-30% by 2080s. Climate and the human activities can influence the land cover status and the eco-environmental quality. There are enough evidences that there is strong interaction between climate variability and ecosystems. A project was carried out in Gandaki river basin in central Nepal to analyze the relationship of NDVI vegetation index with the temperature, rainfall and snowcover information. The relationships were analyzed for different landuses classes-grassland, forest and agriculture. Results show that the snowcover area is decreasing at the rate of 0.15% per year in the basin. The NDVI shows seasonal fluctuations and lightly correlated with the rainfall and temperature.

The fish fauna in tropical rivers: the case of the Sorocaba River basin, São Paulo, Brazil.

PubMed

Smith, Welber Senteio; Petrere Júnior, Miguel; Barrella, Walter

2003-01-01

A survey was carried out on the fish species in the Sorocaba River basin, the main tributary of the left margin of the Tietê River, located in the State of São Paulo, Brazil. The species were collected with gill nets. After identification of the specimens, their relative abundance, weight and standard length were determined. Up to the present moment there are not any studies that focus this subject in this hydrographic basin. Fifty-three species, distributed in eighteen families and six orders were collected. Characiformes were represented by twenty-eight species, Siluriformes by seventeen species, the Gymnotiformes by three species, Perciformes and Cyprinodontiformes by two species, and the Synbranchiformes by one species. Among the collected species there were two exotic. The most abundant species were Astyanax fasciatus and Hypostomus ancistroides. In relation to total weight the most representative species were Hoplias malabaricus and Hypostomus ancistroides. Cyprinus carpio, Prochilodus lineatus, Schizodon nasutus and Hoplias malabaricus were the most representative species in relation to average weight. Largest standard length were recorded for Sternopygus macrurus, Steindachnerina insculpta, Eigenmannia aff. virescens and Cyprinus carpio.

A Geomorphologic Synthesis of Nonlinearity in Surface Runoff

NASA Astrophysics Data System (ADS)

Wang, C. T.; Gupta, Vijay K.; Waymire, Ed

1981-06-01

The geomorphic approach leading to a representation of an instantaneous unit hydrograph (iuh) which we developed earlier is generalized to incorporate nonlinear effects in the rainfall-runoff transformation. It is demonstrated that the nonlinearity in the transformation enters in part through the dependence of the mean holding time on the rainfall intensity. Under an assumed first approximation that this dependence is the sole source of nonlinearity an explicit quasi-linear representation results for the rainfall- runoff transformation. The kernel function of this transformation can be termed as the instantaneous response function (irf) in contradistinction to the notion of an iuh for the case of a linear rainfall-runoff transformation. The predictions from the quasi-linear theory agree very well with predictions from the kinematic wave approach for the one small basin that is analyzed. Also, for two large basins in Illinois having areas of about 1100 mi2 the predictions from the quasi-linear approach compare very well with the observed flows. A measure of nonlinearity, α naturally arises through the dependence of the mean holding time KB(i0) on the rainfall intensity i0via KB (i0) ˜ i0 -α. Computations of α for four basins show that α approaches ⅔ as basin size decreases and approaches zero as the basin size increases. A semilog plot of α versus the square root of the basin area gives a straight line. Confirmation of this relationship for other basins would be of basic importance in predicting flows from ungaged basins.

Insights and participatory actions driven by a socio-hydrogeological approach for groundwater management: the Grombalia Basin case study (Tunisia)

NASA Astrophysics Data System (ADS)

Tringali, C.; Re, V.; Siciliano, G.; Chkir, N.; Tuci, C.; Zouari, K.

2017-08-01

Sustainable groundwater management strategies in water-scarce countries need to guide future decision-making processes pragmatically, by simultaneously considering local needs, environmental problems and economic development. The socio-hydrogeological approach named `Bir Al-Nas' has been tested in the Grombalia region (Cap Bon Peninsula, Tunisia), to evaluate the effectiveness of complementing hydrogeochemical and hydrogeological investigations with the social dimension of the issue at stake (which, in this case, is the identification of groundwater pollution sources). Within this approach, the social appraisal, performed through social network analysis and public engagement of water end-users, allowed hydrogeologists to get acquainted with the institutional dimension of local groundwater management, identifying issues, potential gaps (such as weak knowledge transfer among concerned stakeholders), and the key actors likely to support the implementation of the new science-based management practices resulting from the ongoing hydrogeological investigation. Results, hence, go beyond the specific relevance for the Grombaila basin, showing the effectiveness of the proposed approach and the importance of including social assessment in any given hydrogeological research aimed at supporting local development through groundwater protection measures.

U.S. Geological Survey middle Rio Grande basin study; proceedings of the third annual workshop, Albuquerque, New Mexico, February 24-25, 1999

USGS Publications Warehouse

Bartolino, James R.

1999-01-01

Approximately 40 percent (about 600,000 people) of the total population of New Mexico lives within the Middle Rio Grande Basin, which includes the City of Albuquerque. Ongoing analyses of the central portion of the Middle Rio Grande Basin by the U.S. Geological Survey (USGS) in cooperation with the City of Albuquerque and other agencies have shown that ground water in the basin is not as readily accessible as earlier studies indicated. A more complete characterization of the ground-water resources of the entire Middle Rio Grande Basin is hampered by a scarcity of data in the northern and southern areas of the basin. The USGS Middle Rio Grande Basin study is a 5-year effort by the USGS and other agencies to improve the understanding of the hydrology, geology, and land-surface characteristics of the Middle Rio Grande Basin. The primary objective of this study is to improve the understanding of the water resources of the basin. Of particular interest is to determine the extent of hydrologic connection between the Rio Grande and the Santa Fe Group aquifer. Additionally, ground-water quality affects the availability of water supplies in the basin. Improving the existing USGS-constructed ground-water flow model of the Middle Rio Grande Basin will integrate all the various tasks that improve our knowledge of the various components of the Middle Rio Grande water budget. Part of this improvement will be accompanied by extended knowledge of the aquifer system beyond the Albuquerque area into the northern and southern reaches of the basin. Other improvements will be based on understanding gained through process-oriented research and improved geologic characterization of the deposits. The USGS and cooperating agencies will study the hydrology, geology, and land-surface characteristics of the basin to provide the scientific information needed for water-resources management and for managers to plan for water supplies needed for a growing population. To facilitate exchange of information among the scientists working on the Middle Rio Grande Basin study, yearly technical meetings have been held for each of the first 3 years of the anticipated 5-year study. These meetings provide an opportunity to present research results and plan new field efforts. This report documents the results of research presented at the third annual technical workshop held in Albuquerque, New Mexico, February 24-25, 1999. The report is organized into this introduction and five chapters that focus on Middle Rio Grande Basin study investigations in progress in the Middle Rio Grande Basin. The first chapter describes geographic data and analysis efforts in the basin. The second chapter details work being done on the hydrogeologic and geologic framework of the basin. The third chapter describes studies on ground-water recharge in the basin. The fourth chapter provides details on the research on the ground-water flow system in the basin, including modeling efforts. The fifth chapter is devoted to an overview of New Mexico District Cooperative Program studies in the basin. The information in this report presents preliminary results of an evolving study. As the study progresses and individual projects publish their results in more detail, the USGS hopes to expand the scientific basis needed for management decisions regarding the Middle Rio Grande Basin.

Trend analysis of vegetation in Louisiana's Atchafalaya river basin

USGS Publications Warehouse

O'Neil, Calvin P.; deSteiguer, J. Edward; North, Gary W.

1978-01-01

The purpose of the study was to determine vegetation succession trends; produce a current vegetation map of the basin; and to develop a mathematical model capable of predicting vegetation changes based on hydrologic factors. A statistical relationship of forests and hydrological variables with forest succession constraints predicted forest acreage totals for 16 forest categories within 70% or better of actual values in two-thirds of the cases. Using time-lapsed photography covering 42 years, 23 categories were described. The succession trend of vegetation since 1930, by sedimentation, had been toward mixed hardwoods, except for isolated areas. Satellite MSS Band 7 imagery was used to map the current vegetation into three main categories and for assessment of acreage. Additionally, a geological anomaly was recognized on satellite imagery indication an effect on drainage and sedimentation.

Effects of Jefferson Road stormwater-detention basin on loads and concentrations of selected chemical constituents in East Branch of Allen Creek at Pittsford, Monroe County, New York

USGS Publications Warehouse

Sherwood, Donald A.

2004-01-01

Discharge and water-quality data collection at East Branch Allen Creek from 1990 through 2000 provide a basis for estimating the effect of the Jefferson Road detention basin on loads and concentrations of chemical constituents downstream from the basin. Mean monthly flow for the 5 years prior to construction of the detention basin (8.71 ft3/s) was slightly lower than after (9.08 ft3/s). The slightly higher mean monthly flow after basin construction may have been influenced by the peak flow for the period of record that occurred in July 1998 or variations in flow diverted from the canal. No statistically significant difference in average monthly mean flow before and after basin installation was indicated.Total phosphorus was the only constituent to show no months with significant differences in load after basin construction. Several constituents showed months with significantly smaller loads after basin construction than before, whereas some constituents showed certain months with smaller and some months with greater loads, after basin construction. Statistical analysis of the "mean monthly load" for all months before and all months after construction of the detention basin showed only one constituent (ammonia + organic nitrogen) with a significantly lower load after construction and none with higher loads.Median concentrations of ammonia + organic nitrogen showed a statistically significant decrease (from 0.78 mg/L to 0.60 mg/L) after basin installation, as did nitrite + nitrate (from 1.50 mg/L to 0.96 mg/L); in contrast, the median concentration of dissolved chloride increased from 95.5 mg/L before basin installation to 109 mg/L thereafter. A trend analysis of constituent concentrations before and after installation of the detention basin showed that total phosphorus had a downward trend after installation.Analysis of the data collected at East Branch Allen Creek indicates that the Jefferson Road detention basin, in some cases, provides an improvement (reduction) in loads of some constituents. These results are uncertain, however, because hydrologic conditions before basin installation differed from those in the 5 years that followed, and because inflow from the Erie-Barge canal may alter the water quality in the 1-mi reach between the basin outflow and the gaging station.

Assessment of ecological security based on soil and water conservation: a case study from Gansu Province, China

NASA Astrophysics Data System (ADS)

Li, Z. J.; Tian, Q.; Song, L. L.

2016-08-01

In this study, the analytic hierarchy process (ahp), ecological security index(S) and PSR model were used to evaluate Gansu's ecological security based on the large number of survey data. The results indicated that Gansu's ecological security index increased from 0.31 in 1986 to 0.66 in 2013, which reflected ecological security was in sensitive state (0.7༞S≥⃒0.5). The main reason was that national policy on protecting the ecological environment has played a crucial role, especially the national project of returning farmland to forest and grass carried out in recent years. Moreover, the environmental issues such as the higher PM2.5, sand storms and climate extremes, had significantly improved people's environmental awareness in the study area. The regional difference of ecological security index was significant in Gansu Provinces, and the part of Yangtze river basin was higher than the part of Yellow River basin, whiles the in-land river basin was the lowest value. In a world, Gansu's ecological security had improved in recent years, but there was strong need for paying more attention to policy for ecological environment protection and increasing the propaganda to ensure the Gansu's ecological security in the future. This study will provide a scientific basis for the sustainable development of regional social economy and ecological environment.

Developing a Science-based River Basin Management Plan for the Kharaa River Basin, Mongolia

NASA Astrophysics Data System (ADS)

Karthe, Daniel

2013-04-01

The Kharaa River Basin (KRB), which is located north of Mongolia's capital Ulaanbaatar and south of Lake Baikal, was chosen as a model region for the development and implementation of an integrated water resources management consisting of a monitoring concept, technical measures and a capacity development program (Karthe et al. 2012a). The basin of the Kharaa River covers an area of 14534 km² that is partly mountaineous and largely covered by taiga and steppe. At its outlet, the 362 km Kharaa River has a mean long-term annual discharge of 12.1 m³/s (MoMo Consortium 2009). A highly continental climate results in limited water resources, and rising water consumption coupled with the effects of climate and land use change may in the future exacerbate this water scarcity (Malsy et al. 2012; Karthe et al. 2013). Whereas the environment in the upper part of the catchment is in a relatively pristine state, the mid- and downstream sections of the river are characterized by nearby industry, mining activities and intensive agriculture (Menzel et al. 2011), resulting in declining water quality and ultimately a degradation of aquatic ecosystems (Hofmann et al. 2010; Hartwig et al. 2012). Moreover, it is a problem for the supply of major cities like Darkhan which largely rely on alluvial aquifers containing shallow-depth groundwater (Mun et al. 2008). Currently, there are alarming signs of water quality deterioration. With regard to water provision, a major problem is the poor state of distribution infrastructures which were often built in the 1960s and 70s (Scharaw & Westerhoff 2011). Rather little is currently known about the water quality supplied to end users; the latter is even more dubious in the city's informal ger districts (Karthe et al. 2012b). One important goal of the research and development project "Integrated Water Resources Management in Central Asia: Model Region Mongolia" lies in the implementation of a holistic concept for water resources monitoring and management. In the past, shared and unclear responsibilities, a spatial mismatch between administrative and river basin boundaries, the lack of relevant information, financial resources and implementation capacity resulted in an uncoordinated and partially uncontrolled exploitation of water resources (Livingstone et al. 2009; Horlemann et al. 2012). The recent decision of the Mongolian government to develop river basin management plans and to provide for their implementation through river basin councils and administrations, and the comparatively good data availability resulting from the R&D project, resulted in the decision to jointly develop a science-based river basin management plan for the KRB as a model region for other river basins of the country. References: Hartwig, M.; Theuring, P.; Rode, M. & Borchardt, D. (2012): Suspended sediments in the Kharaa River catchment (Mongolia) and its impact on hyporheic zone functions. Environmental Earth Sciences 65(5):1535-1546. Hofmann, J.; Venohr, M.; Behrendt, H. & Opitz, D. (2010): Integrated Water Resources Management in Central Asia: Nutrient and heavy metal emissions and their relevance for the Kharaa River Basin, Mongolia. Water Science and Technology 62(2):353-363. Horlemann, L. & Dombrowsky, I. (2012): Institutionalising IWRM in developing and transition countries: the case of Mongolia. Environmental Earth Sciences 65(5):1547-1559. Karthe, D.; Borchardt, D. & Hufert, F. (2012a): Implementing IWRM: Experiences from a Central Asian Model Region. In: Pandya, A.B. (Ed.) (2012): India Water Week 2012. Water, Energy and Food Security: Call for Solutions, Part A3, pp. 1-15. Delhi: Ministry of Water Resources, Government of India. Karthe, D.; Sigel, K.; Scharaw, B. et al. (2012b): Towards an integrated concept for monitoring and improvements in water supply, sanitation and hygiene (WASH) in urban Mongolia. Water & Risk 20:1-5. Karthe, D.; Malsy, M.; Kopp, B. & Minderlein, S. (2013): Assessing Water Availibility and its Drivers in the Context of an Integrated Water Resources Management (IWRM): A Case Study from the Kharaa River Basin, Mongolia. GeoÖko (submitted). Livingstone, A.J.; Erdenechimeg, C. & Oyunsuvd, A. (2009): Needs assessment on institutional capacity for water governance in Mongolia. Ulaan Baatar: Government of Mongolia & UNDP Mongolia. Malsy, M.; aus der Beek, T.; Eisner, S. & Flörke, M. (2012): Climate Change impacts on Central Asian water resources. Advances in Geosciences 32:77-83. Menzel, L.; Hofmann, J. & Ibisch, R. (2011): Untersuchung von Wasser- und Stoffflüssen als Grundlage für ein Integriertes Wasserressourcen - Management im Kharaa-Einzugsgebiet (Mongolei). Hydrologie und Wasserbewirtschaftung 55(2):88-103. MoMo Consortium (2009): Integrated Water Resources Management for Central Asia: Model Region Mongolia (MoMo). Case Study in the Kharaa River Basin. Final Project Report. Mun, Y.; Ko, I.H.; Janchivdorj, L. et al. (2008): Integrated Water Management Model on the Selenge River Basin: Status Survey and Investigation (Phase I). Seoul: KEI Publications. Scharaw, B. & T. Westerhoff (2011): A Leak Detection in Drinking Water Distribution Network of Darkhan in Framework of the Project Integrated Water Resources Management in Central Asia, Model Region Mongolia. Proceedings of the IWA 1st Central Asian Regional Young and Senior Water Professionals Conference, Almaty/Kazakhstan, pp. 275-282.

Defining boundaries across borders: a case study extending a major land resource area into Mexico

Treesearch

Rebecca MacEwen; Roy S. Mann; Philip Heilman; Jeffry J. Stone; Alicia Melgoza Castillo; D. Phillip Guertin

2005-01-01

Geographic information science (GIS) and field work were applied to extend Major Land Resource Area (MLRA) 41, Southeastern Arizona Basin and Range, from Arizona and New Mexico into Sonora and Chihuahua, Mexico. The result of this analysis is a tentative boundary line that delineates MLRA 41 for both the United States and Mexico based on elevation, soils, temperature,...

Groundwater quality in the Monterey Bay and Salinas Valley groundwater basins, California

USGS Publications Warehouse

Kulongoski, Justin T.; Belitz, Kenneth

2011-01-01

The Monterey-Salinas study unit is nearly 1,000 square miles and consists of the Santa Cruz Purisima Formation Highlands, Felton Area, Scotts Valley, Soquel Valley, West Santa Cruz Terrace, Salinas Valley, Pajaro Valley, and Carmel Valley groundwater basins (California Department of Water Resources, 2003; Kulongski and Belitz, 2011). These basins were grouped into four study areas based primarily on geography. Groundwater basins in the north were grouped into the Santa Cruz study area, and those to the south were grouped into the Monterey Bay, the Salinas Valley, and the Paso Robles study areas (Kulongoski and others, 2007). The study unit has warm, dry summers and cool, moist winters. Average annual rainfall ranges from 31 inches in Santa Cruz in the north to 13 inches in Paso Robles in the south. The study areas are drained by several rivers and their principal tributaries: the Salinas, Pajaro, and Carmel Rivers, and San Lorenzo Creek. The Salinas Valley is a large intermontane valley that extends southeastward from Monterey Bay to Paso Robles. It has been filled, up to a thickness of 2,000 feet, with Tertiary and Quaternary marine and terrestrial sediments that overlie granitic basement. The Miocene-age Monterey Formation and Pliocene- to Pleistocene-age Paso Robles Formation, and Pleistocene to Holocene-age alluvium contain freshwater used for supply. The primary aquifers in the study unit are defined as those parts of the aquifers corresponding to the perforated intervals of wells listed in the California Department of Public Health database. Public-supply wells are typically drilled to depths of 200 to 650 feet, consist of solid casing from the land surface to depths of about 175 to 500 feet, and are perforated below the solid casing. Water quality in the primary aquifers may differ from that in the shallower and deeper parts of the aquifer system. Groundwater movement is generally from the southern part of the Salinas Valley north towards the Monterey Bay. Land use in the study unit is about 44 percent (%) natural (mostly grassland and forests), 43% agricultural, and 13% urban. The primary agricultural uses are row crops, pasture, hay, and vineyards. The largest urban areas are the cities of Santa Cruz, Watsonville, Monterey, Salinas, King City, and Paso Robles. Recharge to the groundwater system is primarily from stream-channel infiltration from the major rivers and their tributaries, and from infiltration of water from precipitation and irrigation. The primary sources of discharge are water pumped for irrigation and municipal supply, evaporation, and discharge to streams.

Stochastic or statistic? Comparing flow duration curve models in ungauged basins and changing climates

NASA Astrophysics Data System (ADS)

Müller, M. F.; Thompson, S. E.

2015-09-01

The prediction of flow duration curves (FDCs) in ungauged basins remains an important task for hydrologists given the practical relevance of FDCs for water management and infrastructure design. Predicting FDCs in ungauged basins typically requires spatial interpolation of statistical or model parameters. This task is complicated if climate becomes non-stationary, as the prediction challenge now also requires extrapolation through time. In this context, process-based models for FDCs that mechanistically link the streamflow distribution to climate and landscape factors may have an advantage over purely statistical methods to predict FDCs. This study compares a stochastic (process-based) and statistical method for FDC prediction in both stationary and non-stationary contexts, using Nepal as a case study. Under contemporary conditions, both models perform well in predicting FDCs, with Nash-Sutcliffe coefficients above 0.80 in 75 % of the tested catchments. The main drives of uncertainty differ between the models: parameter interpolation was the main source of error for the statistical model, while violations of the assumptions of the process-based model represented the main source of its error. The process-based approach performed better than the statistical approach in numerical simulations with non-stationary climate drivers. The predictions of the statistical method under non-stationary rainfall conditions were poor if (i) local runoff coefficients were not accurately determined from the gauge network, or (ii) streamflow variability was strongly affected by changes in rainfall. A Monte Carlo analysis shows that the streamflow regimes in catchments characterized by a strong wet-season runoff and a rapid, strongly non-linear hydrologic response are particularly sensitive to changes in rainfall statistics. In these cases, process-based prediction approaches are strongly favored over statistical models.

Comparing statistical and process-based flow duration curve models in ungauged basins and changing rain regimes

NASA Astrophysics Data System (ADS)

Müller, M. F.; Thompson, S. E.

2016-02-01

The prediction of flow duration curves (FDCs) in ungauged basins remains an important task for hydrologists given the practical relevance of FDCs for water management and infrastructure design. Predicting FDCs in ungauged basins typically requires spatial interpolation of statistical or model parameters. This task is complicated if climate becomes non-stationary, as the prediction challenge now also requires extrapolation through time. In this context, process-based models for FDCs that mechanistically link the streamflow distribution to climate and landscape factors may have an advantage over purely statistical methods to predict FDCs. This study compares a stochastic (process-based) and statistical method for FDC prediction in both stationary and non-stationary contexts, using Nepal as a case study. Under contemporary conditions, both models perform well in predicting FDCs, with Nash-Sutcliffe coefficients above 0.80 in 75 % of the tested catchments. The main drivers of uncertainty differ between the models: parameter interpolation was the main source of error for the statistical model, while violations of the assumptions of the process-based model represented the main source of its error. The process-based approach performed better than the statistical approach in numerical simulations with non-stationary climate drivers. The predictions of the statistical method under non-stationary rainfall conditions were poor if (i) local runoff coefficients were not accurately determined from the gauge network, or (ii) streamflow variability was strongly affected by changes in rainfall. A Monte Carlo analysis shows that the streamflow regimes in catchments characterized by frequent wet-season runoff and a rapid, strongly non-linear hydrologic response are particularly sensitive to changes in rainfall statistics. In these cases, process-based prediction approaches are favored over statistical models.

Implementation of Theeuropeanwater Framework Directive In France: New Challenges For River Basin Organisat Ion, Planning and Participation

NASA Astrophysics Data System (ADS)

Allain, S.

The European Water Framework Directive (2000/60/EC) establishes a system of participatory river basin planning for national and international basins. The French institutional framework for water management is already very close to this system: the 1964 Water Law actually set up basin bodies, the Agences de l'Eau ("Water Agencies"), at the level of large river basins, and multipartite basin commissions, the Comités de Bassin ("River Basin Authorities"), in order to monitor the Agences de l'Eau's policies; besides, the 1992 Water Law created a planning procedure at this level, the Schéma Directeur d'Aménagement et de Gestion des Eaux (SDAGE : "General Water Management Plan"), aiming to determine general orientations for the management of water resources and having to be defined by the Comités de Bassin. At first glance therefore, the implementation of the European Water Framework Directive should not raise a lot of problems in France. However, a quick analysis of the current situation shows that it is not so obvious : if the French Water Policy set up two basin organisations, neither of them deals concretely with the management of the water resources, and the implementation of water management plans depends on many stakeholders; the SDAGE itself only partially meets the demands of the Directive, regarding e. g. the economic analysis; finally, in spite of the creation of multipartite basin commissions, the public participation is very restricted. Such an analysis leads to pay more attention to the relations to establish between organisation, planning and participation at the level of large river basins. An analysis of other elements of the French institutional framework can help us in this way : another planning procedure was actually created by the 1992 Water Law, the Schéma d'Aménagement et de Gestion des Eaux (SAGE : "Water Management Plan"), aiming to fix general objectives to manage the water resources at the level of small river basins, and having to be defined and implemented by a new tripartite entity, the Commission Locale de l'Eau (CLE : Local Water Commission), which can be considered as a real river basin organisation; an empirical analysis of the implementation of such a procedure can offer therefore many new insights and the paper will present the results of an analysis of 10 case studies. But it will be also necessary to put such an experience side by side with the political will to develop public debates and to extend the roles of the Commission Nationale du Débat Public ("Public Debate National Commission").

Morphostructural characterization of the Charco basin and its surrounding areas in the Chihuahua segment of north Mexican Basin and Range Province

NASA Astrophysics Data System (ADS)

Troiani, Francesco; Menichetti, Marco

2014-05-01

The Chihuahua Basin and Range (CBR) is the eastern branch of the northern Mexican Basin and Range Province that, from a morphostructural point of view, presently is one amongst the lesser-known zones of the southern portion of the North America Basin and Range Province. The study area covers an approximately 800 km2-wide portion of the CBR and encompasses the fault-bounded Charco basin and its surrounding areas. The bedrock of the area pertains to the large siliceous-igneous province of the Sierra Madre Occidental and consists of volcanoclastic rocks including Oligocene dacite, rhyolite, rhyolitic tuffs, and polimitic conglomerates. The region is characterized by a series of NW-SE oriented valleys delimited by tilted monoclinal blocks bounded by high angle, SW-dipping, normal faults. Abrupt changes in elevation, alternating between narrow faulted mountain chains and flat arid valleys or basins are the main morphological elements of the area. The valleys correspond to structural grabens filled with Plio-Pleistocene continental sediments. These grabens are about 10 km wide, while the extensional fault system extend over a distance of more than 15 km. The mountain ranges are in most cases continuous over distances that range from 10 to 70 km including different branches of the extensional and transfer faults. The morphogenesis is mainly erosive in character: erosional landforms (such as rocky scarps, ridges, strath-terraces, erosional pediment, reverse slopes, landslide scar zones, litho-structural flat surfaces) dominate the landscape. In contrast, Quaternary depositional landforms are mainly concentrated within the flat valleys or basins. The Quaternary deposits consist of wide alluvial fans extending to the foot of the main ridges, fluvial and debris-slope deposits. The morphostructural characterization of the area integrated different methodologies, including: i) geomorphological and structural field analyses; ii) remote sensing and geo-morphometric investigations based on aerial photos and Digital Elevation Models (a 28x28 m DEM and high-resolution LIDAR dataset in key sites), and iii) geophysical investigations (high resolution reflection seismic profiling combined with refraction seismic tomography). The main outputs of this research are as follows: i) the Charco basin master-faults and their conjugate extensional system were geometrically characterized and their main associated landforms mapped and described; ii) the morphostratigraphic correlations amongst both deformed and tectonically unaffected Quaternary deposits revealed that the Charco basin master fault has been inactive over the Holocene; iii) the main extensional fault system is associated with conjugate faults, oriented approximately SSW-NNE, that segmented the Charco basin master faults and favored the deposition of the most recent piedmont fans along the eastern margin of the basin; iv) the local morphostructures had played a dominant influence on the Quaternary evolution of both drainage network and relief landforms.

Microbial-caddisfly bioherm association from the Lower Cretaceous Shinekhudag Formation, Mongolia: Earliest record of plant armoring in fossil caddisfly cases.

PubMed

Adiya, Tsolmon; Johnson, Cari L; Loewen, Mark A; Ritterbush, Kathleen A; Constenius, Kurt N; Dinter, Cory M

2017-01-01

Caddisfly larvae construct underwater protective cases using surrounding materials, thus providing information on environmental conditions in both modern and ancient systems. Microbial bioherms associated with caddisfly cases are found in the Berriassian-Hauterivian (~140-130 Ma) Shinekhudag Formation of Mongolia, and yield new insights into aspects of lacustrine paleoecosystems and paleoenvironments. This formation contains the earliest record of plant-armored caddisfly cases and a rare occurrence of microbial-caddisfly association from the Mesozoic. The bioherms are investigated within the context of stratigraphic correlations, depositional environment interpretations, and basin-evolution models of the sedimentary fill. The bioherms form 0.5-2.0 m diameter mound-shaped bodies and are concentrated within a single, oil shale-bound stratigraphic interval. Each bioherm is composed of up to 40% caddisfly cases along with stromatolites of millimeter-scale, micritic laminations. Petrographic analyses reveal these bioherms are composed of non-systematic associations of columnar and oncoidal microbialites, constructed around colonies of caddisfly cases. The cases are straight to curved, slightly tapered, and tube-shaped, with a progressively increasing length and width trend (7-21 mm by 1.5-2.5 mm). Despite these variations, the case architectures reveal similar construction materials; the particles used for cases are dominated by plant fragments, ostracod valves, carbonate rocks, and rare mica and feldspar grains. Allochems within the bioherms include ooids, ostracods, plant fragments, rare gastropods, feldspar grains bound in micritic matrices, and are consolidated by carbonate dominated cements. The combination of microbial-caddisfly association, plant fragment case particles, and ooids/oncoids are indicative of a shallow, littoral lake setting. Stratigraphic juxtaposition of nearshore bioherms and the bounding distal oil-shale facies suggests that the bioherms developed in an underfilled lake basin, resulting from an abrupt and short-lived lake desiccation event. Lake chemistry is believed to have been relatively alkaline, saline to hypersaline, and rich in Ca, Mg, and HCO3 ions. Through analyzing bioherm characteristics, caddisfly case architecture, carbonate microfacies, and stratigraphic variability, we infer larger-scale processes that controlled basin development during their formation.

Microbial-caddisfly bioherm association from the Lower Cretaceous Shinekhudag Formation, Mongolia: Earliest record of plant armoring in fossil caddisfly cases

PubMed Central

Johnson, Cari L.; Loewen, Mark A.; Ritterbush, Kathleen A.; Constenius, Kurt N.; Dinter, Cory M.

2017-01-01

Caddisfly larvae construct underwater protective cases using surrounding materials, thus providing information on environmental conditions in both modern and ancient systems. Microbial bioherms associated with caddisfly cases are found in the Berriassian-Hauterivian (~140–130 Ma) Shinekhudag Formation of Mongolia, and yield new insights into aspects of lacustrine paleoecosystems and paleoenvironments. This formation contains the earliest record of plant-armored caddisfly cases and a rare occurrence of microbial-caddisfly association from the Mesozoic. The bioherms are investigated within the context of stratigraphic correlations, depositional environment interpretations, and basin-evolution models of the sedimentary fill. The bioherms form 0.5–2.0 m diameter mound-shaped bodies and are concentrated within a single, oil shale-bound stratigraphic interval. Each bioherm is composed of up to 40% caddisfly cases along with stromatolites of millimeter-scale, micritic laminations. Petrographic analyses reveal these bioherms are composed of non-systematic associations of columnar and oncoidal microbialites, constructed around colonies of caddisfly cases. The cases are straight to curved, slightly tapered, and tube-shaped, with a progressively increasing length and width trend (7–21 mm by 1.5–2.5 mm). Despite these variations, the case architectures reveal similar construction materials; the particles used for cases are dominated by plant fragments, ostracod valves, carbonate rocks, and rare mica and feldspar grains. Allochems within the bioherms include ooids, ostracods, plant fragments, rare gastropods, feldspar grains bound in micritic matrices, and are consolidated by carbonate dominated cements. The combination of microbial-caddisfly association, plant fragment case particles, and ooids/oncoids are indicative of a shallow, littoral lake setting. Stratigraphic juxtaposition of nearshore bioherms and the bounding distal oil-shale facies suggests that the bioherms developed in an underfilled lake basin, resulting from an abrupt and short-lived lake desiccation event. Lake chemistry is believed to have been relatively alkaline, saline to hypersaline, and rich in Ca, Mg, and HCO3 ions. Through analyzing bioherm characteristics, caddisfly case architecture, carbonate microfacies, and stratigraphic variability, we infer larger-scale processes that controlled basin development during their formation. PMID:29161280

Bibliography, geophysical data locations, and well core listings for the Mississippi Interior Salt Basin

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

1998-05-01

To date, comprehensive basin analysis and petroleum system modeling studies have not been performed on any of the basins in the northeastern Gulf of Mexico. Of these basins, the Mississippi Interior Salt Basin has been selected for study because it is the most petroliferous basin in the northeastern Gulf of Mexico, small- and medium-size companies are drilling the majority of the exploration wells. These companies do not have the resources to perform basin analysis or petroleum system modeling research studies nor do they have the resources to undertake elaborate information searches through the volumes of publicly available data at themore » universities, geological surveys, and regulatory agencies in the region. The Advanced Geologic Basin Analysis Program of the US Department of Energy provides an avenue for studying and evaluating sedimentary basins. This program is designed to improve the efficiency of the discovery of the nation`s remaining undiscovered oil resources by providing improved access to information available in the public domain and by increasing the amount of public information on domestic basins. This report provides the information obtained from Year 1 of this study of the Mississippi Interior Salt Basin. The work during Year 1 focused on inventorying the data files and records of the major information repositories in the northeastern Gulf of Mexico and making these inventories easily accessible in an electronic format.« less

Magnitude and Frequency of Rural Floods in the Southeastern United States, through 2006: Volume 2, North Carolina

USGS Publications Warehouse

Weaver, J. Curtis; Feaster, Toby D.; Gotvald, Anthony J.

2009-01-01

Reliable estimates of the magnitude and frequency of floods are required for the economical and safe design of transportation and water-conveyance structures. A multistate approach was used to update methods for estimating the magnitude and frequency of floods in rural, ungaged basins in North Carolina, South Carolina, and Georgia that are not substantially affected by regulation, tidal fluctuations, or urban development. In North Carolina, annual peak-flow data available through September 2006 were available for 584 sites; 402 of these sites had a total of 10 or more years of systematic record that is required for at-site, flood-frequency analysis. Following data reviews and the computation of 20 physical and climatic basin characteristics for each station as well as at-site flood-frequency statistics, annual peak-flow data were identified for 363 sites in North Carolina suitable for use in this analysis. Among these 363 sites, 19 sites had records that could be divided into unregulated and regulated/ channelized annual peak discharges, which means peak-flow records were identified for a total of 382 cases in North Carolina. Considering the 382 cases, at-site flood-frequency statistics are provided for 333 unregulated cases (also used for the regression database) and 49 regulated/channelized cases. The flood-frequency statistics for the 333 unregulated sites were combined with data for sites from South Carolina, Georgia, and adjacent parts of Alabama, Florida, Tennessee, and Virginia to create a database of 943 sites considered for use in the regional regression analysis. Flood-frequency statistics were computed by fitting logarithms (base 10) of the annual peak flows to a log-Pearson Type III distribution. As part of the computation process, a new generalized skew coefficient was developed by using a Bayesian generalized least-squares regression model. Exploratory regression analyses using ordinary least-squares regression completed on the initial database of 943 sites resulted in defining five hydrologic regions for North Carolina, South Carolina, and Georgia. Stations with drainage areas less than 1 square mile were removed from the database, and a procedure to examine for basin redundancy (based on drainage area and periods of record) also resulted in the removal of some stations from the regression database. Flood-frequency estimates and basin characteristics for 828 gaged stations were combined to form the final database that was used in the regional regression analysis. Regional regression analysis, using generalized least-squares regression, was used to develop a set of predictive equations that can be used for estimating the 50-, 20-, 10-, 4-, 2-, 1-, 0.5-, and 0.2-percent chance exceedance flows for rural ungaged, basins in North Carolina, South Carolina, and Georgia. The final predictive equations are all functions of drainage area and the percentage of drainage basin within each of the five hydrologic regions. Average errors of prediction for these regression equations range from 34.0 to 47.7 percent. Discharge estimates determined from the systematic records for the current study are, on average, larger in magnitude than those from a previous study for the highest percent chance exceedances (50 and 20 percent) and tend to be smaller than those from the previous study for the lower percent chance exceedances when all sites are considered as a group. For example, mean differences for sites in the Piedmont hydrologic region range from positive 0.5 percent for the 50-percent chance exceedance flow to negative 4.6 percent for the 0.2-percent chance exceedance flow when stations are grouped by hydrologic region. Similarly for the same hydrologic region, median differences range from positive 0.9 percent for the 50-percent chance exceedance flow to negative 7.1 percent for the 0.2-percent chance exceedance flow. However, mean and median percentage differences between the estimates from the previous and curre

U.S. Geological Survey Middle Rio Grande Basin Study; Proceedings of the first annual workshop, Denver, Colorado, November 12-14, 1996

USGS Publications Warehouse

Bartolino, James R.

1997-01-01

Approximately 40 percent (about 600,000 people) of the total population of New Mexico lives within the Middle Rio Grande Basin, which includes the City of Albuquerque. Ongoing analyses of the central portion of the Middle Rio Grande Basin by the U.S. Geological Survey (USGS) in cooperation with the City of Albuquerque and other cooperators have shown that ground water in the basin is not as readily accessible as earlier studies indicated. A more complete characterization of the ground-water resources of the entire Middle Rio Grande Basin is hampered by a scarcity of data in the northern and southern areas of the basin. The USGS Middle Rio Grande Basin Study is a 5-year effort by the USGS and other agencies to improve the understanding of the hydrology, geology, and land-surface characteristics of the Middle Rio Grande Basin. The primary objective of this study is to improve the understanding of the water resources of the basin. Of particular interest is to determine the extent of hydrologic connection between the Rio Grande and the Santa Fe Group aquifer. Additionally, ground-water quality affects the availability of water supplies in the basin. Improving the existing USGS- constructed ground-water flow model of the Middle Rio Grande Basin will integrate all the various tasks that improve our knowledge of the various components of the Middle Rio Grande water budget. Part of this improvement will be accompanied by extended knowledge of the aquifer system beyond the Albuquerque area into the northern and southern reaches of the basin. Other improvements will be based on understanding gained through process-oriented research and improved geologic characterization of the deposits. The USGS will study the hydrology, geology, and land-surface characteristics of the basin to provide the scientific information needed for water- resources management and for managers to plan for water supplies needed for a growing population. To facilitate exchange of information among the many USGS scientists working in the Middle Rio Grande Basin, yearly technical meetings are planned for the anticipated 5-year study. These meetings provide an opportunity to present research results and plan new field efforts. This report documents the results of research presented at the first technical workshop held in Denver, Colorado, in November 1996. The report is organized into this introduction, five chapters that focus on USGS investigations in progress in the Middle Rio Grande Basin, and three appendixes with supplemental information. The first chapter provides an overview of the USGS program in the basin. The second chapter describes geographic data and analysis efforts in the basin. The third chapter details work being done on the hydrogeologic framework of the basin. The fourth chapter describes studies on ground-water availability in the basin and is divided into three areas of research: ground-water/surface-water interaction, ground-water flow and aquifer properties, and recharge. The fifth chapter is devoted to an overview of New Mexico District Cooperative Program studies in the basin. Finally, the appendixes list publications and presentations made during the first year of the study and 1996 workshop attendees. The report concludes with a list of selected references relevant to the study. The information in this report presents preliminary results of an evolving study. As the study progresses and individual projects publish their results in more detail, the USGS hopes to expand the scientific basis needed for management decisions regarding the Middle Rio Grande Basin.

Selected geohydrologic data from a regional aquifer-system analysis of the Northern Rocky Mountains intermontane basins in Idaho

USGS Publications Warehouse

Stone, M.A.; Parliman, D.J.; Schaefer, J.L.

1996-01-01

The U.S. Geological Survey began a regional aquifer-system analysis of the Northern Rocky Mountains of northern and central Idaho and western Montana in 1990. The analysis helped establish a regional framework of information for aquifers in about 70 ntermontane basins in an area of 80,000 square miles. In many areas, ground water is the only suitable source of supply, yet little information is available about this resource. Selected geohydrologic data from 1,004 wells in 19 intermontane basins in Idaho were compiled as part of the regional analysis. Data consist of basin name and well number, altitude of land surface, date of well construction, geologic unit, depth of well, diameter of casing, type of finish, top of open interval, primary use of water, date of water level measurement, water level, discharge, specific capacity, source of discharge data, type of log available, date of water-quality constituent measurement, specific conductance, pH, and temperature. A similar report for intermontane basins in Montana has been published by the U.S. Geologcial Survey in Montana. (USGS)

Sedimentologic and reservoir characteristics under the tectono-sequence stratigraphic framework: A case study from the Early Cretaceous, upper Abu Gabra sandstones, Sufyan Sub-basin, Muglad Basin, Sudan

NASA Astrophysics Data System (ADS)

Yassin, Mohamed A.; Hariri, Mustafa M.; Abdullatif, Osman M.; Makkawi, M.; Bertotti, G.; Kaminski, Michael A.

2018-06-01

The Sufyan Sub-basin is an east-west trending Sub-basin located in the northwestern part of the Muglad Basin, in the eastern extension of the West and Central Africa Rift System (WCARS). Exploration results showed the occurrence of accumulations of hydrocarbon. The source rock for these hydrocarbons is believed to be the lacustrine shale of the Abu Gabra Formation. Fluvio-deltaic sandstones within the Abu Gabra Formation represent the primary reservoir. Depositional and post-depositional processes influence reservoir heterogeneity, quality, and architecture. This study investigates different scales of reservoir heterogeneities from basin to micro scale and discusses the impact of depositional facies and diagenesis on reservoir quality. Approaches include seismic interpretation, seismic attribute analysis, well log analysis, thin sections and scanning electron microscope (SEM) investigations, and X-ray diffraction (XRD) analysis of the Abu Gabra Formation. Sedimentologic interpretation in this study was performed based on core cuttings, well logs, and seismic data. Subsurface facies analysis was analyzed based on the description of six conventional cores from two wells. Seven lithofacies in Abu Gabra Formation are identified. Four types of depositional systems are identified in the studied succession. These are braided delta, fan delta, sublacustrine fan, and lacustrine systems. The sandstone is medium to coarse-grained, poorly to moderately sorted and sub-angular to sub-rounded, sub-feldspathic arenite to quartz arenite. At the basin scale, the Abu Gabra Formation showed different sandstone bodies thickness, geometry, and architecture and are ascribed to different depositional systems. At macro and meso-scales, reservoir quality varies within the Abu Gabra reservoir where it shows progressive coarsening upward tendencies with different degrees of connectivity. The upper part of the reservoir is well connected with amalgamated sandstone bodies, however, the middle to lower parts have moderate to low sandstone body connectivity and amalgamation. At a micro-scale, sandstone reservoir quality is directly affected by texture and diagenesis. The XRD and SEM analyses show that kaolinite and chlorite clay are the common clay minerals in the studied samples. Clay matrix and quartz overgrowth have significantly reduced the reservoir porosity and permeability, while the dissolution of feldspars during the diagenetic process increase it. The estimated porosity in Abu Gabra Formation ranges from 5 to 21% with an average of 13%; while permeability varies from 0.22 to 732 mD with an average of 240 mD. The results of this study contribute to a better understanding of reservoir heterogeneities and help in reservoir quality prediction, therefore enhancing the hydrocarbon productivity.

Structural equation model of total phosphorus loads in the Red River of the North Basin, USA and Canada

USGS Publications Warehouse

Ryberg, Karen R.

2017-01-01

Attribution of the causes of trends in nutrient loading is often limited to correlation, qualitative reasoning, or references to the work of others. This paper represents efforts to improve causal attribution of water-quality changes. The Red River of the North basin provides a regional test case because of international interest in the reduction of total phosphorus loads and the availability of long-term total phosphorus data and ancillary geospatial data with the potential to explain changes in water quality over time. The objectives of the study are to investigate structural equation modeling methods for application to water-quality problems and to test causal hypotheses related to the drivers of total phosphorus loads over the period 1970 to 2012. Multiple working hypotheses that explain total phosphorus loads and methods for estimating missing ancillary data were developed, and water-quality related challenges to structural equation modeling (including skewed data and scaling issues) were addressed. The model indicates that increased precipitation in season 1 (November–February) or season 2 (March–June) would increase total phosphorus loads in the basin. The effect of agricultural practices on total phosphorus loads was significant, although the effect is about one-third of the effect of season 1 precipitation. The structural equation model representing loads at six sites in the basin shows that climate and agricultural practices explain almost 60% of the annual total phosphorus load in the Red River of the North basin. The modeling process and the unexplained variance highlight the need for better ancillary long-term data for causal assessments.

Dynamics of a minimal consumer network with bi-directional influence

NASA Astrophysics Data System (ADS)

Ekaterinchuk, Ekaterina; Jungeilges, Jochen; Ryazanova, Tatyana; Sushko, Iryna

2018-05-01

We study the dynamics of a model of interdependent consumer behavior defined by a family of two-dimensional noninvertible maps. This family belongs to a class of coupled logistic maps with different nonlinearity parameters and coupling terms that depend on one variable only. In our companion paper we considered the case of independent consumers as well as the case of uni-directionally connected consumers. The present paper aims at describing the dynamics in the case of a bi-directional connection. In particular, we investigate the bifurcation structure of the parameter plane associated with the strength of coupling between the consumers, focusing on the mechanisms of qualitative transformations of coexisting attractors and their basins of attraction.

Runoff characteristics and non-point source pollution analysis in the Taihu Lake Basin: a case study of the town of Xueyan, China.

PubMed

Zhu, Q D; Sun, J H; Hua, G F; Wang, J H; Wang, H

2015-10-01

Non-point source pollution is a significant environmental issue in small watersheds in China. To study the effects of rainfall on pollutants transported by runoff, rainfall was monitored in Xueyan town in the Taihu Lake Basin (TLB) for over 12 consecutive months. The concentrations of different forms of nitrogen (N) and phosphorus (P), and chemical oxygen demand, were monitored in runoff and river water across different land use types. The results indicated that pollutant loads were highly variable. Most N losses due to runoff were found around industrial areas (printing factories), while residential areas exhibited the lowest nitrogen losses through runoff. Nitrate nitrogen (NO3-N) and ammonia nitrogen (NH4-N) were the dominant forms of soluble N around printing factories and hotels, respectively. The levels of N in river water were stable prior to the generation of runoff from a rainfall event, after which they were positively correlated to rainfall intensity. In addition, three sites with different areas were selected for a case study to analyze trends in pollutant levels during two rainfall events, using the AnnAGNPS model. The modeled results generally agreed with the observed data, which suggests that AnnAGNPS can be used successfully for modeling runoff nutrient loading in this region. The conclusions of this study provide important information on controlling non-point source pollution in TLB.

Combined use of local and global hydrometeorological data with regional and global hydrological models in the Magdalena - Cauca river basin, Colombia

NASA Astrophysics Data System (ADS)

Rodriguez, Erasmo; Sanchez, Ines; Duque, Nicolas; Lopez, Patricia; Kaune, Alexander; Werner, Micha; Arboleda, Pedro

2017-04-01

The Magdalena Cauca Macrobasin (MCMB) in Colombia, with an area of about 257,000 km2, is the largest and most important water resources system in the country. With almost 80% of the Colombian population (46 million people) settled in the basin, it is the main source of water for demands including human consumption, agriculture, hydropower generation, industrial activities and ecosystems. Despite its importance, the basin has witnessed enormous changes in land-cover and extensive deforestation during the last three decades. To make things more complicated, the MCMB currently lacks a set of tools to support planning and decision making processes at scale of the whole watershed. Considering this, the MCMB has been selected as one of the six different regional case studies in the eartH2Observe research project, in which hydrological and meteorological reanalysis products are being validated for the period 1980-2012. The combined use of the hydrological and meteorological reanalysis data, with local hydrometeorological data (precipitation, temperature and streamflow) provided by the National Hydrometeorological Agency (IDEAM), has given us the opportunity to implement and test three hydrological models (VIC, WFLOW and a Water Balance Model based on the Budyko framework) at the basin scale. Additionally, results from the global models in the eartH2Observe hydrological reanalysis have been used to evaluate their performance against the observed streamflow data. This paper discusses the comparison between streamflow observations and simulations from the global hydrological models forced with the WFDEI data, and regional models forced with a combination of observed and meteorological reanalysis data, in the whole domain of the MCMB. For the three regional models analysed results show good performances for some sub-basins and poor performances for others. This can be due to the smoothing of the precipitation fields, interpolated from point daily rainfall data, the effect of horizontal precipitation (not included in the models) and weaknesses in the models structures; for example the poor performance of the VIC model in base flow dominated basins. In order to improve these simulations a strategy based on a hydrological model ensemble is currently being developed in the case study. Results from the global models, show that these consistently tend to overestimate runoff. This may be due to the coarse resolution used (50 km), biases in the ERA-Interim precipitation forcing, and the different partitioning within the global models of the precipitation into evapotranspiration and runoff. It is expected that within the Tier II hydrological reanalysis, where the models will produce outputs at 25 km resolution, some improvements may be identified.

Characterization of the regional variability of flood regimes within the Omo-Gibe River Basin, Ethiopia

NASA Astrophysics Data System (ADS)

Yared, Adanech; Demissie, Solomon S.; Sivapalan, Murugesu; Viglione, Alberto; MacAlister, Charlotte

2014-05-01

Hydrological variability and seasonality is one of the Ethiopia's primary water resource management challenges. Variability is most obviously manifest in endemic, devastating droughts and floods. While the level of flooding is quite often extremely high and destroys human beings and property, in many cases flooding is of vital importance because the community benefits from flood recession agriculture. This is the case of the lower Omo plain whose agriculture is based on the regularity of the inundations due to flooding of the Omo Gibe River. The big flood in 2006, which caused death for more than 300 people and 2000 cattle, poses a dilemma. Flooding must be controlled and regulated in a way that the damages are reduced as much as possible but the flooding-related benefits are not lost. To this aim, characterization and understanding of hydrological variability of the Omo Gibe River basin is fundamental. The goal of this work is to extract the maximal amount of information on the hydrological variability and specially on the flooding regime from the few data available in the region. Because most of the basin is ungauged, hydrological information is reconstructed using the data from 9 gauged catchments. A daily water balance model has been developed, calibrated and validated for 9 gauged catchments and, subsequently, the parameters have been correlated to catchment characteristics in order to establish a functional relationship that allows to apply the model to ungauged catchments. Daily streamflow has been predicted for 15 ungauged catchments, which are assumed to comprehensively represent the hydrological variability of the Omo-Gibe River Basin. Even though both northern and southern catchments are affected by a strong seasonality of precipitation, with most of the rain falling in less than 3 months, most of the northern catchments are humid, while in the southern part of the Omo-Gibe River basin, the catchments are either humid, dry sub humid, semiarid or arid. As for climate, also landscape and vegetation cover is more homogeneous in the northern part of the Omo Gibe River basin than in the southern part. Consequently, the runoff variability reflects the interesting diversity of climate and landscape of the basin. The gradient of flooding regimes from the north to the south of the Omo Gibe River basin will be analysed and the impacts of possible regime changes will be discussed.

Identifying stakeholder-relevant climate change impacts: a case study in the Yakima River Basin, Washington, USA

USGS Publications Warehouse

Jenni, K.; Graves, D.; Hardiman, Jill M.; Hatten, James R.; Mastin, Mark C.; Mesa, Matthew G.; Montag, J.; Nieman, Timothy; Voss, Frank D.; Maule, Alec G.

2014-01-01

Designing climate-related research so that study results will be useful to natural resource managers is a unique challenge. While decision makers increasingly recognize the need to consider climate change in their resource management plans, and climate scientists recognize the importance of providing locally-relevant climate data and projections, there often remains a gap between management needs and the information that is available or is being collected. We used decision analysis concepts to bring decision-maker and stakeholder perspectives into the applied research planning process. In 2009 we initiated a series of studies on the impacts of climate change in the Yakima River Basin (YRB) with a four-day stakeholder workshop, bringing together managers, stakeholders, and scientists to develop an integrated conceptual model of climate change and climate change impacts in the YRB. The conceptual model development highlighted areas of uncertainty that limit the understanding of the potential impacts of climate change and decision alternatives by those who will be most directly affected by those changes, and pointed to areas where additional study and engagement of stakeholders would be beneficial. The workshop and resulting conceptual model highlighted the importance of numerous different outcomes to stakeholders in the basin, including social and economic outcomes that go beyond the physical and biological outcomes typically reported in climate impacts studies. Subsequent studies addressed several of those areas of uncertainty, including changes in water temperatures, habitat quality, and bioenergetics of salmonid populations.

Groundwater quality in the Antelope Valley, California

USGS Publications Warehouse

Dawson, Barbara J. Milby; Belitz, Kenneth

2012-01-01

Groundwater provides more than 40 percent of California’s drinking water. To protect this vital resource, the State of California created the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The Priority Basin Project of the GAMA Program provides a comprehensive assessment of the State’s groundwater quality and increases public access to groundwater-quality information. Antelope Valley is one of the study areas being evaluated. The Antelope study area is approximately 1,600 square miles (4,144 square kilometers) and includes the Antelope Valley groundwater basin (California Department of Water Resources, 2003). Antelope Valley has an arid climate and is part of the Mojave Desert. Average annual rainfall is about 6 inches (15 centimeters). The study area has internal drainage, with runoff from the surrounding mountains draining towards dry lakebeds in the lower parts of the valley. Land use in the study area is approximately 68 percent (%) natural (mostly shrubland and grassland), 24% agricultural, and 8% urban. The primary crops are pasture and hay. The largest urban areas are the cities of Palmdale and Lancaster (2010 populations of 152,000 and 156,000, respectively). Groundwater in this basin is used for public and domestic water supply and for irrigation. The main water-bearing units are gravel, sand, silt, and clay derived from surrounding mountains. The primary aquifers in Antelope Valley are defined as those parts of the aquifers corresponding to the perforated intervals of wells listed in the California Department of Public Health database. Public-supply wells in Antelope Valley are completed to depths between 360 and 700 feet (110 to 213 meters), consist of solid casing from the land surface to a depth of 180 to 350 feet (55 to 107 meters), and are screened or perforated below the solid casing. Recharge to the groundwater system is primarily runoff from the surrounding mountains, and by direct infiltration of irrigation and sewer and septic systems. The primary sources of discharge are pumping wells and evapotranspiration near the dry lakebeds.

Groundwater quality in Coachella Valley, California

USGS Publications Warehouse

Dawson, Barbara J. Milby; Belitz, Kenneth

2012-01-01

Groundwater provides more than 40 percent of California’s drinking water. To protect this vital resource, the State of California created the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The Priority Basin Project of the GAMA Program provides a comprehensive assessment of the State’s groundwater quality and increases public access to groundwater-quality information. Coachella Valley is one of the study areas being evaluated. The Coachella study area is approximately 820 square miles (2,124 square kilometers) and includes the Coachella Valley groundwater basin (California Department of Water Resources, 2003). Coachella Valley has an arid climate, with average annual rainfall of about 6 inches (15 centimeters). The runoff from the surrounding mountains drains to rivers that flow east and south out of the study area to the Salton Sea. Land use in the study area is approximately 67 percent (%) natural, 21% agricultural, and 12% urban. The primary natural land cover is shrubland. The largest urban areas are the cities of Indio and Palm Springs (2010 populations of 76,000 and 44,000, respectively). Groundwater in this basin is used for public and domestic water supply and for irrigation. The main water-bearing units are gravel, sand, silt, and clay derived from surrounding mountains. The primary aquifers in Coachella Valley are defined as those parts of the aquifers corresponding to the perforated intervals of wells listed in the California Department of Public Health database. Public-supply wells in Coachella Valley are completed to depths between 490 and 900 feet (149 to 274 meters), consist of solid casing from the land surface to a depth of 260 to 510 feet (79 to 155 meters), and are screened or perforated below the solid casing. Recharge to the groundwater system is primarily runoff from the surrounding mountains, and by direct infiltration of irrigation. The primary sources of discharge are pumping wells, evapotranspiration, and underflow to the Salton Sea and Imperial Valley areas.

Geodatabase of sites, basin boundaries, and topology rules used to store drainage basin boundaries for the U.S. Geological Survey, Colorado Water Science Center

USGS Publications Warehouse

Dupree, Jean A.; Crowfoot, Richard M.

2012-01-01

This geodatabase and its component datasets are part of U.S. Geological Survey Digital Data Series 650 and were generated to store basin boundaries for U.S. Geological Survey streamgages and other sites in Colorado. The geodatabase and its components were created by the U.S. Geological Survey, Colorado Water Science Center, and are used to derive the numeric drainage areas for Colorado that are input into the U.S. Geological Survey's National Water Information System (NWIS) database and also published in the Annual Water Data Report and on NWISWeb. The foundational dataset used to create the basin boundaries in this geodatabase was the National Watershed Boundary Dataset. This geodatabase accompanies a U.S. Geological Survey Techniques and Methods report (Book 11, Section C, Chapter 6) entitled "Digital Database Architecture and Delineation Methodology for Deriving Drainage Basins, and Comparison of Digitally and Non-Digitally Derived Numeric Drainage Areas." The Techniques and Methods report details the geodatabase architecture, describes the delineation methodology and workflows used to develop these basin boundaries, and compares digitally derived numeric drainage areas in this geodatabase to non-digitally derived areas. 1. COBasins.gdb: This geodatabase contains site locations and basin boundaries for Colorado. It includes a single feature dataset, called BasinsFD, which groups the component feature classes and topology rules. 2. BasinsFD: This feature dataset in the "COBasins.gdb" geodatabase is a digital container that holds the feature classes used to archive site locations and basin boundaries as well as the topology rules that govern spatial relations within and among component feature classes. This feature dataset includes three feature classes: the sites for which basins have been delineated (the "Sites" feature class), basin bounding lines (the "BasinLines" feature class), and polygonal basin areas (the "BasinPolys" feature class). The feature dataset also stores the topology rules (the "BasinsFD_Topology") that constrain the relations within and among component feature classes. The feature dataset also forces any feature classes inside it to have a consistent projection system, which is, in this case, an Albers-Equal-Area projection system. 3. BasinsFD_Topology: This topology contains four persistent topology rules that constrain the spatial relations within the "BasinLines" feature class and between the "BasinLines" feature class and the "BasinPolys" feature classes. 4. Sites: This point feature class contains the digital representations of the site locations for which Colorado Water Science Center basin boundaries have been delineated. This feature class includes point locations for Colorado Water Science Center active (as of September 30, 2009) gages and for other sites. 5. BasinLines: This line feature class contains the perimeters of basins delineated for features in the "Sites" feature class, and it also contains information regarding the sources of lines used for the basin boundaries. 6. BasinPolys: This polygon feature class contains the polygonal basin areas delineated for features in the "Sites" feature class, and it is used to derive the numeric drainage areas published by the Colorado Water Science Center.

Genesis analysis of high-gamma ray sandstone reservoir and its log evaluation techniques: a case study from the Junggar basin, northwest China.

PubMed

Wang, Liang; Mao, Zhiqiang; Sun, Zhongchun; Luo, Xingping; Song, Yong; Liu, Zhen

2013-01-01

In the Junggar basin, northwest China, many high gamma-ray (GR) sandstone reservoirs are found and routinely interpreted as mudstone non-reservoirs, with negative implications for the exploration and exploitation of oil and gas. Then, the high GR sandstone reservoirs' recognition principles, genesis, and log evaluation techniques are systematically studied. Studies show that the sandstone reservoirs with apparent shale content greater than 50% and GR value higher than 110API can be regarded as high GR sandstone reservoir. The high GR sandstone reservoir is mainly and directly caused by abnormally high uranium enrichment, but not the tuff, feldspar or clay mineral. Affected by formation's high water sensitivity and poor borehole quality, the conventional logs can not recognize reservoir and evaluate the physical property of reservoirs. Then, the nuclear magnetic resonance (NMR) logs is proposed and proved to be useful in reservoir recognition and physical property evaluation.

Genesis Analysis of High-Gamma Ray Sandstone Reservoir and Its Log Evaluation Techniques: A Case Study from the Junggar Basin, Northwest China

PubMed Central

Wang, Liang; Mao, Zhiqiang; Sun, Zhongchun; Luo, Xingping; Song, Yong; Liu, Zhen

2013-01-01

In the Junggar basin, northwest China, many high gamma-ray (GR) sandstone reservoirs are found and routinely interpreted as mudstone non-reservoirs, with negative implications for the exploration and exploitation of oil and gas. Then, the high GR sandstone reservoirs' recognition principles, genesis, and log evaluation techniques are systematically studied. Studies show that the sandstone reservoirs with apparent shale content greater than 50% and GR value higher than 110API can be regarded as high GR sandstone reservoir. The high GR sandstone reservoir is mainly and directly caused by abnormally high uranium enrichment, but not the tuff, feldspar or clay mineral. Affected by formation's high water sensitivity and poor borehole quality, the conventional logs can not recognize reservoir and evaluate the physical property of reservoirs. Then, the nuclear magnetic resonance (NMR) logs is proposed and proved to be useful in reservoir recognition and physical property evaluation. PMID:24078797

Chemical equilibria of thermal waters for the application of geothermometers from the Guanzhong basin, China

NASA Astrophysics Data System (ADS)

Xilai, Zheng; Armannsson, Halldor; Yongle, Li; Hanxue, Qiu

2002-03-01

In this study, representative samples from thermal wells and springs were chemically analyzed and geothermometers were used to calculate the deep temperatures of geothermal reservoirs on the basis of water-mineral equilibrium. In some cases, however, the chemical components are not in equilibrium with the minerals in the reservoir. Therefore, log( Q/ K) diagrams are used to study the chemical equilibrium for the minerals that are likely to participate. The Na-K-Mg triangular diagram is also applied to evaluate the equilibrium of water with reservoir rocks. Standard curves at the reference temperatures are prepared to reveal which type of silica geothermometer is appropriate for the specified condition. This study shows that water samples from geothermal wells W9 and W12 are in equilibrium with the selective minerals, and chalcedony may control the fluid-silica equilibrium. It is estimated that there is an exploitable low-temperature reservoir with possible temperatures of 80-90°C in the Guanzhong basin.

Excitation of secondary Love and Rayleigh waves in athree-dimensional sedimentary basin evaluated by the direct boundary element method with normal modes

NASA Astrophysics Data System (ADS)

Hatayama, Ken; Fujiwara, Hiroyuki

1998-05-01

This paper aims to present a new method to calculate surface waves in 3-D sedimentary basin models, based on the direct boundary element method (BEM) with vertical boundaries and normal modes, and to evaluate the excitation of secondary surface waves observed remarkably in basins. Many authors have so far developed numerical techniques to calculate the total 3-D wavefield. However, the calculation of the total wavefield does not match our purpose, because the secondary surface waves excited on the basin boundaries will be contaminated by other undesirable waves. In this paper, we prove that, in principle, it is possible to extract surface waves excited on part of the basin boundaries from the total 3-D wavefield with a formulation that uses the reflection and transmission operators defined in the space domain. In realizing this extraction in the BEM algorithm, we encounter the problem arising from the lateral and vertical truncations of boundary surfaces extending infinitely in the half-space. To compensate the truncations, we first introduce an approximate algorithm using 2.5-D and 1-D wavefields for reference media, where a 2.5-D wavefield means a 3-D wavefield with a 2-D subsurface structure, and we then demonstrate the extraction. Finally, we calculate the secondary surface waves excited on the arc shape (horizontal section) of a vertical basin boundary subject to incident SH and SV plane waves propagating perpendicularly to the chord of the arc. As a result, we find that in the SH-incident case the Love waves are predominantly excited, rather than the Rayleigh waves and that in the SV-wave incident case the Love waves as well as the Rayleigh waves are excited. This suggests that the Love waves are more detectable than the Rayleigh waves in the horizontal components of observed recordings.

Investigation of the structure and lithology of bedrock concealed by basin fill, using ground-based magnetic-field-profile data acquired in the San Rafael Basin, southeastern Arizona

USGS Publications Warehouse

Bultman, Mark W.

2013-01-01

Data on the Earth’s total-intensity magnetic field acquired near ground level and at measurement intervals as small as 1 m include information on the spatial distribution of nearsurface magnetic dipoles that in many cases are unique to a specific lithology. Such spatial information is expressed in the texture (physical appearance or characteristics) of the data at scales of hundreds of meters to kilometers. These magnetic textures are characterized by several descriptive statistics, their power spectrum, and their multifractal spectrum. On the basis of a graphical comparison and textural characterization, ground-based magnetic-field profile data can be used to estimate bedrock lithology concealed by as much as 100 m of basin fill in some cases, information that is especially important in assessing and exploring for concealed mineral deposits. I demonstrate that multifractal spectra of ground-based magnetic-field-profile data can be used to differentiate exposed lithologies and that the shape and position of the multifractal spectrum of the ground-based magnetic-field-profile of concealed lithologies can be matched to the upward-continued multifractal spectrum of an exposed lithology to help distinguish the concealed lithology. In addition, ground-based magnetic-field-profile data also detect minute differences in the magnetic susceptibility of rocks over small horizontal and vertical distances and so can be used for precise modeling of bedrock geometry and structure, even when that bedrock is concealed by 100 m or more of nonmagnetic basin fill. Such data contain valuable geologic information on the bedrock concealed by basin fill that may not be so visible in aeromagnetic data, including areas of hydrothermal alteration, faults, and other bedrock structures. Interpretation of these data in the San Rafael Basin, southeastern Arizona, has yielded results for estimating concealed lithologies, concealed structural geology, and a concealed potential mineral-resource target.

The role of storage capacity in coping with intra-annual runoff variability on a global scale

NASA Astrophysics Data System (ADS)

Gaupp, Franziska; Hall, Jim; Dadson, Simon

2015-04-01

Intra-annual variability poses a risk to water security in many basins as runoff is unevenly distributed over the year. Areas such as Northern Africa, Australia and the South-Western USA are characterized by a high coefficient of variability of monthly runoff. Analyzing the global risk of water scarcity, this study examines 680 basin-country units (BCUs) (403 river basins divided by country borders). By calculating the water balance for each BCU, the interplay of runoff on the one hand and domestic, industrial and environmental water needs on the other hand is shown. In contrast to other studies on average water scarcity, this work focuses on variability of water supply as metrics based on annual average water availability and demand can underestimate the risk of scarcity. The model is based on the assumption that each country-basin with sub-basins and tributaries can be treated as one single reservoir with storage capacity aggregated over that BCU. It includes surface runoff and the possibility to withdraw groundwater as water supply. The storage capacity of each BCU represents the ability to transfer water from wet months to dry months in order to buffer and cope with intra-annual water supply variability and to meet total water demand. Average monthly surface runoff per country-basin for the period 1979 to 2012 is derived from outcomes of the hydrological model Mac-PDM. Mac-PDM is forced with monthly ERAI-Interim reanalysis climate data on a one degree resolution. Groundwater withdrawal capacity, total water demand and storage capacity are taken from the IMPACT model provided by the International Food Research Institute (IFPRI). Storage refers to any kind of surface reservoir whose water can be managed and used for human activities in the industrial, domestic and agricultural sectors. Groundwater withdrawal capacity refers to the technological capacity to pump water rather than the amount of groundwater available. Total water demand includes consumptive water use from the industrial, domestic and agricultural sectors and varies between months. Due to a lack of data, the 2010 figures for groundwater withdrawal capacity are assumed to be equally distributed over 12 months without accounting for possible variation within a year. For runoff and water demand, monthly data are used. Our study shows that storage capacity helps to cope with intra-annual water variability and thereby decreases the risk of water scarcity. Several cases emerge where water security is critically dependent on transboundary flows such as the Nile in Egypt or the Aral Drainage in Uzbekistan. Furthermore, we calculate environmental flow requirements using the Variable Monthly Flow (VMF) method and analyse the effects of abstraction and dam construction on environmental flows. For each BCU, we examine whether environmental water requirements can be met with given human abstractions. Additionally, water scarcity is examined for the case when water is reserved for the environment and cannot be abstracted for human purposes.

Assessment of climate change impacts on meteorological and hydrological droughts in the Jucar River Basin

NASA Astrophysics Data System (ADS)

Marcos-Garcia, Patricia; Pulido-Velazquez, Manuel; Lopez-Nicolas, Antonio

2016-04-01

Extreme natural phenomena, and more specifically droughts, constitute a serious environmental, economic and social issue in Southern Mediterranean countries, common in the Mediterranean Spanish basins due to the high temporal and spatial rainfall variability. Drought events are characterized by their complexity, being often difficult to identify and quantify both in time and space, and an universally accepted definition does not even exist. This fact, along with future uncertainty about the duration and intensity of the phenomena on account of climate change, makes necessary increasing the knowledge about the impacts of climate change on droughts in order to design management plans and mitigation strategies. The present abstract aims to evaluate the impact of climate change on both meteorological and hydrological droughts, through the use of a generalization of the Standardized Precipitation Index (SPI). We use the Standardized Flow Index (SFI) to assess the hydrological drought, using flow time series instead of rainfall time series. In the case of the meteorological droughts, the Standardized Precipitation and Evapotranspiration Index (SPEI) has been applied to assess the variability of temperature impacts. In order to characterize climate change impacts on droughts, we have used projections from the CORDEX project (Coordinated Regional Climate Downscaling Experiment). Future rainfall and temperature time series for short (2011-2040) and medium terms (2041-2070) were obtained, applying a quantile mapping method to correct the bias of these time series. Regarding the hydrological drought, the Témez hydrological model has been applied to simulate the impacts of future temperature and rainfall time series on runoff and river discharges. It is a conceptual, lumped and a few parameters hydrological model. Nevertheless, it is necessary to point out the time difference between the meteorological and the hydrological droughts. The case study is the Jucar river basin (Spain), a highly regulated system with a share of 80% of water use for irrigated agriculture. The results show that the climate change would increase the historical drought impacts in the river basin. Acknowledgments The study has been supported by the IMPADAPT project (CGL2013-48424-C2-1-R) with Spanish MINECO (Ministerio de Economía y Competitividad) and European FEDER funds.

River mixing in the Amazon as a driver of concentration-discharge relationships

NASA Astrophysics Data System (ADS)

Moquet, Jean-Sébastien; Bouchez, Julien; Carlo Espinoza, Jhan; Martinez, Jean-Michel; Guyot, Jean-Loup; Lagane, Christelle; Filizola, Naziano; Aniceto, Keila; Noriega, Luis; Hidalgo Sanchez, Liz; Pombosa, Rodrigo; Fraizy, Pascal; Santini, William; Timouk, Franck; Vauchel, Philippe

2017-04-01

Large hydrological systems such as continental-scale river basins aggregate water from compositionally different tributaries. Here we explore how such aggregation can affect solute concentration-discharge (C-Q) relationships and thus obscure the message carried by these relationships in terms of weathering properties of the Critical Zone. We compute 10 day-frequency time series of Q and major solute (Si, Ca2+, Mg2+, K+, Na+, Cl-, SO42-) C and fluxes (F) for 13 gauging stations of the SNO-HYBAM Monitoring Program (Geodynamical, hydrological and Biogeochemical control of erosion/weathering and material transport in the Amazon, Orinoco and Congo basins) located throughout the Amazon basin, the largest river basin in the world. Concentration-discharge relationships vary in a systematic manner, shifting for most solutes from a nearly "chemostatic" behavior (constant C) at the Andean mountain front to a more "dilutional" pattern (negative C-Q relationship) towards the system mouth. Associated to this shift in trend is a shift in shape: C-Q hysteresis becomes more prominent at the most downstream stations. A simple model of tributary mixing allows us to identify the important parameters controlling C-Q trends and shapes in the mixture, and we show that for the Amazon case, the model results are in qualitative agreement with the observations. Altogether, this study suggests that mixing of water and solutes between different flowpaths leads to altered C-Q relationships.

Characterizing hydrological activities over Yangtze River basin using the new HUST-Grace2016 model, MODIS, and NCEP/NCAR data

NASA Astrophysics Data System (ADS)

Zhou, H.; Luo, Z.; Tangdamrongsub, N.; He, L.

2017-12-01

Accurate TWS estimation is important to evaluate the situation of the water resource over the Yangtze River basin. This study exploits the TWS observation from the new gravity model, HUST-Grace06, which is developed by a new low-frequency noise processing strategy. A novel GRACE post-processing approach is proposed to enhance the quality of the TWS estimate, and the improved TWS is used to characterize the hydrological activities over the Yangtze River basin. The approach includes the effective noise reduction and the leakage error mitigation based on forward modeling. The HUST-Grace06 derived TWS presents good agreement with the CSR mascon solution as well as the PCR-GLOBWB hydrological model. Particularly, our solution provides remarkable performance in identifying the extreme climate events e.g., flood and drought over the Yangtze River basin. In addition, for the first time, the NCEP/NCAR reanalysis data is incorporated with GRACE in the exploration of the climate induced hydrological activities. The comparison between GRACE and the MODIS-derived NDVI data is also conducted to investigate their connection regarding temporal and spatial distribution. The analysis suggests that the terrestrial reflectance data can be used to represent the TWS information. Importantly, such information can be used to fill the missing data in case of the early termination of GRACE or during the prelaunch of the GRACE Follow-On mission.

The Borderlands - A region of physical and cultural diversity: Chapter 2 in United States-Mexican Borderlands: Facing tomorrow's challenges through USGS science

USGS Publications Warehouse

Parcher, Jean W.; Papoulias, Diana M.; Woodward, Dennis G.; Durall, Roger A.

2013-01-01

The area surrounding the United States–Mexican border is very physically and culturally diverse and cannot be generalized by any single description. To assist in an accurate appraisal and understanding of this remarkable region, the Borderlands team has divided it into eight subareas based on the watershed subareas of the U.S. Geological Survey Border Environmental Health Initiative (http://borderhealth.cr.usgs.gov) (fig. 2–1), the boundaries of which are defined primarily by surface-water drainage basins. The drainage basins directly adjacent to or crossing the international boundary were automatically included in the defined border region, as were those basins that contain unconsolidated aquifers that extend to or cross the international boundary. Also, “protected areas” adjacent to included basins were selectively added to the defined border region. Though some geographic features are entirely within the Borderlands, many features—deserts, mountain ranges, rivers, etc.— extend beyond the region boundaries but are still influential to Borderlands environments (fig. 2–2). In some cases, the authors of the following chapters have made fine adjustments to the Borderlands boundaries, and they have described those alterations where necessary. By describing and studying these subareas individually and comparing them to one another, we can emphasize the physical and cultural diversity that makes the Borderlands such an important geographic area.

Enhancing sedimentation by improving flow conditions using parallel retrofit baffles.

PubMed

He, Cheng; Scott, Eric; Rochfort, Quintin

2015-09-01

In this study, placing parallel-connected baffles in the vicinity of the inlet was proposed to improve hydraulic conditions for enhancing TSS (total suspended solids) removal. The purpose of the retrofit baffle design is to divide the large and fast inflow into smaller and slower flows to increase flow uniformity. This avoids short-circuiting and increases residence time in the sedimentation basin. The newly proposed parallel-connected baffle configuration was assessed in the laboratory by comparing its TSS removal performance and the optimal flow residence time with those from the widely used series-connected baffles. The experimental results showed that the parallel-connected baffles outperformed the series-connected baffles because it could disperse flow faster and in less space by splitting the large inflow into many small branches instead of solely depending on flow internal friction over a longer flow path, as was the case under the series-connected baffles. Being able to dampen faster flow before entering the sedimentation basin is critical to reducing the possibility of disturbing any settled particles, especially under high inflow conditions. Also, for a large sedimentation basin, it may be more economically feasible to deploy the proposed parallel retrofit baffle in the vicinity of the inlet than series-connected baffles throughout the entire settling basin. Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved.

Sources of water pollution and evolution of water quality in the Wuwei basin of Shiyang river, Northwest China.

PubMed

Ma, Jinzhu; Ding, Zhenyu; Wei, Guoxiao; Zhao, Hua; Huang, Tianming

2009-02-01

Based on surveys and chemical analyses, we performed a case study of the surface water and groundwater quality in the Wuwei basin, in order to understand the sources of water pollution and the evolution of water quality in Shiyang river. Concentrations of major chemical elements in the surface water were related to the distance downstream from the source of the river, with surface water in the upstream reaches of good quality, but the river from Wuwei city to the Hongya reservoir was seriously polluted, with a synthetic pollution index of 25. Groundwater quality was generally good in the piedmont with dominant bicarbonate and calcium ions, but salinity was high and nitrate pollution occurs in the northern part of the basin. Mineralization of the groundwater has changed rapidly during the past 20 years. There are 23 wastewater outlets that discharge a total of 22.4 x 10(6)m(3)y(-1) into the river from Wuwei city, which, combined with a reduction of inflow water, were found to be the major causes of water pollution. Development of fisheries in the Hongya reservoir since 2000 has also contributed to the pollution. The consumption of water must be decreased until it reaches the sustainable level permitted by the available resources in the whole basin, and discharge of wastes must also be drastically reduced.

Climatic Change, Conflict and Peace in Transboundary River Basins - A Theoretical Perspective

NASA Astrophysics Data System (ADS)

Siegfried, T. U.; Beck, L.; Koubi, V.; Bernauer, T.

2011-12-01

Recent research shows that one of the most significant risk for societal development pertains to water availability and that the greatest risks for unrest stemming from economic deprivation and the erosion of livelihoods is found in transboundary river basins in poor and politically unstable parts of the world. While until now, historic linkages between water scarcity and conflict were weak at best, there is growing fear that environmental change will increasingly lead to an entanglement of conflict and resources dynamics in the future. Where resources are not jointly managed in a cooperative way and resources sharing mechanisms not legislated by sound international institutions and were significant impacts from environmental change are expected, these developments give rise to concern. To study environmental change and conflict interlinkages, we develop a formal hydro-climatological model for transboundary freshwater resources and investigate theoretically how climate change translates into potential for conflict and peace, contingent on configurations of power between riparians. The model accounts for how upstream countries exercise power by using water whereas downstream countries use power to obtain water. We show that equilibrium water allocation outcomes are biased towards the more powerful riparian, and that absolute upstream or downstream river basin dominance are limiting cases of our general model. Our model suggests that the basin-wide conflict potential is always more sensitive to changes in relative power between riparian states than to impacts from climatic changes.

Analysis of data characterizing tide and current fluxes in coastal basins

NASA Astrophysics Data System (ADS)

Armenio, Elvira; De Serio, Francesca; Mossa, Michele

2017-07-01

Many coastal monitoring programmes have been carried out to investigate in situ hydrodynamic patterns and correlated physical processes, such as sediment transport or spreading of pollutants. The key point is the necessity to transform this growing amount of data provided by marine sensors into information for users. The present paper aims to outline that it is possible to recognize the recurring and typical hydrodynamic processes of a coastal basin, by conveniently processing some selected marine field data. The illustrated framework is made up of two steps. Firstly, a sequence of analysis with classic methods characterized by low computational cost was executed in both time and frequency domains on detailed field measurements of waves, tides, and currents. After this, some indicators of the hydrodynamic state of the basin were identified and evaluated. Namely, the assessment of the net flow through a connecting channel, the time delay of current peaks between upper and bottom layers, the ratio of peak ebb and peak flood currents and the tidal asymmetry factor exemplify results on the vertical structure of the flow, on the correlation between currents and tide and flood/ebb dominance. To demonstrate how this simple and generic framework could be applied, a case study is presented, referring to Mar Piccolo, a shallow water basin located in the inner part of the Ionian Sea (southern Italy).

Environmental Conditions in a Carpathian Deep Sea Basin During the Period Preceding Oceanic Anoxic Event 2 - A Case Study from the Skole Nappe

NASA Astrophysics Data System (ADS)

Bąk, Krzysztof; Bąk, Marta; Górny, Zbigniew; Wolska, Anna

2015-01-01

Hemipelagic green clayey shales and thin muddy turbidites accumulated in a deep sea environment below the CCD in the Skole Basin, a part of the Outer Carpathian realm, during the Middle Cenomanian. The hemipelagites contain numerous radiolarians, associated with deep-water agglutinated foraminifera. These sediments accumulated under mesotrophic conditions with limited oxygen concentration. Short-term periodic anoxia also occurred during that time. Muddy turbidity currents caused deposition of siliciclastic and biogenic material, including calcareous foramini-fers and numerous sponge spicules. The preservation and diversity of the spicules suggests that they originate from disarticulation of moderately diversified sponge assemblages, which lived predominantly in the neritic-bathyal zone. Analyses of radiolarian ecological groups and pellets reflect the water column properties during the sedimentation of green shales. At that time, surface and also intermediate waters were oxygenated enough and sufficiently rich in nutri-ents to enable plankton production. Numerous, uncompacted pellets with nearly pristine radiolarian skeletons inside show that pelletization was the main factor of radiolarian flux into the deep basin floor. Partly dissolved skeletons indicate that waters in the Skole Basin were undersaturated in relation to silica content. Oxygen content might have been depleted in the deeper part of the water column causing periodic anoxic conditions which prevent rapid bacterial degra-dation of the pellets during their fall to the sea floor.

Biogeochemistry of Arsenic in Groundwater Flow Systems: The Case of Southern Louisiana

NASA Astrophysics Data System (ADS)

Johannesson, K. H.; Yang, N.; Datta, S.

2017-12-01

Arsenic (As) is a highly toxic and carcinogenic metalloid that can cause serious health effects, including increased risk of cancers, infant mortality, and reduced intellectual and motor function in children to populations chronically exposed to As. Recent estimates suggest that more than 140 million people worldwide are drinking As-contaminated groundwater (i.e., As ≥ 10 µg kg-1), and the most severely affected region is the Ganges-Brahmaputra-Meghna delta in Bangladesh and India (i.e., Bengal Basin). Arsenic appears to be mobilized to Bengal Basin groundwaters by reductive dissolution of Fe oxides in aquifer sediments with the source of the labile organic matter occurring in the aquifer sediments. Studies within the lower Mississippi River delta of southern Louisiana (USA) also reveal high As concentrations (up to 640 µg kg-1) in shallow groundwaters. It is not known what affects, if any, the elevated groundwater As has had on local communities. The regional extent of high As shallow groundwaters is controlled, in part, by the distribution of Holocene sediments, deltaic deposits, and organic-rich sediments, similar to the Bengal Basin. Field and laboratory studies suggest that As is largely of geogenic origin, and further that microbial reduction of Fe(III)/Mn(IV) oxides/oxyhydroxides within the sediments contributes the bulk of the As to the groundwaters. Incubation studies are supported by biogeochemical reactive transport modeling, which also indicates reductive dissolution of metal oxides/oxyhydroxides as the likely source of As to these groundwaters. Finally, reactive transport modeling of As in shallow groundwaters suggests that sorption to aquifer mineral surfaces limits the transport of As after mobilization, which may explain, in part, the heterogeneous distribution of As in groundwaters of southern Louisiana and, perhaps, the Bengal Basin.

Assessment of watershed regionalization for the land use change parameterization

NASA Astrophysics Data System (ADS)

Randusová, Beata; Kohnová, Silvia; Studvová, Zuzana; Marková, Romana; Nosko, Radovan

2016-04-01

The estimation of design discharges and water levels of extreme floods is one of the most important parts of the design process for a large number of engineering projects and studies. Floods and other natural hazards initiated by climate, soil, and land use changes are highly important in the 21st century. Flood risks and design flood estimation is particularly challenging. Methods of design flood estimation can be applied either locally or regionally. To obtain the design values in such cases where no recorded data exist, many countries have adopted procedures that fit the local conditions and requirements. One of these methods is the Soil Conservation Service - Curve number (SCS-CN) method which is often used in design flood estimation for ungauged sites. The SCS-CN method is an empirical rainfall-runoff model developed by the USDA Natural Resources Conservation Service (formerly called the Soil Conservation Service or SCS). The runoff curve number (CN) is based on the hydrological soil characteristics, land use, land management and antecedent saturation conditions of soil. This study is focused on development of the SCS-CN methodology for the changing land use conditions in Slovak basins (with the pilot site of the Myjava catchment), which regionalize actual state of land use data and actual rainfall and discharge measurements of the selected river basins. In this study the state of the water erosion and sediment transport along with a subsequent proposal of erosion control measures was analyzed as well. The regionalized SCS-CN method was subsequently used for assessing the effectiveness of this control measure to reduce runoff from the selected basin. For the determination of the sediment transport from the control measure to the Myjava basin, the SDR (Sediment Delivery Ratio) model was used.

Bentonite chemical features as proxy of late Cretaceous provenance changes: A case study from the Western Interior Basin of Canada

NASA Astrophysics Data System (ADS)

Fanti, Federico

2009-05-01

Bentonite beds are fairly common in both marine and terrestrial Upper Cretaceous (Campanian-Maastrichtian) deposits of the Western Interior Basin of western Canada and northwestern United States. A detailed stratigraphic, sedimentologic, geochemical (X-ray fluorescence), and mineralogical (X-ray diffraction) study of twenty-one bentonites from the Puskwaskau and Wapiti formations in the Grande Prairie area (west-central Alberta, Canada) is here presented. Major and trace-element concentrations from altered volcanic ashes document the presence in the study area of predominantly trachyandesitic and rhyolitic volcanogenic products, resulted from intense volcanic arc to within-plate pyroclastic activity. Concentration values of high field strength elements (HFSE) and selected large ion lithophile elements (LILE) (e.g. Nb, Zr, Th, and Y) obtained by X-ray fluorescence spectroscopy strongly support the presence of multiple volcanic sources. Integrated paleoenvironmental and geochemical criteria for provenance determination indicate a bimodal occurrence of basic and acid volcanic products interpreted as reflection of source areas characterized by different tectonic setting and magmatic composition. A comparative analysis of geochemical compositions between Grande Prairie bentonites and 30 known volcanic beds from central and southern Alberta, Manitoba and Montana 1. documents a trend toward more acidic and alkali-depleted volcanic products during the late Campanian-early Maastrichtian interval, and 2. suggests a well constrained stratigraphic and geographic subdivision of the non-marine successions of the foreland basin on the basis of geochemical characteristic of volcanic ash beds. Furthermore, geochemical "fingerprints" of several decimeter to meter thick bentonite beds have been coupled with volcanic ash subsurface signature in order to investigate their role as marker beds. This multiple-approach provides a reliable tool for basin-scale identification and correlation of non-marine sedimentary successions.

Larval fish feeding ecology, growth and mortality from two basins with contrasting environmental conditions of an inner sea of northern Patagonia, Chile.

PubMed

Landaeta, Mauricio F; Bustos, Claudia A; Contreras, Jorge E; Salas-Berríos, Franco; Palacios-Fuentes, Pámela; Alvarado-Niño, Mónica; Letelier, Jaime; Balbontín, Fernando

2015-05-01

During austral spring 2011, a survey was carried out in the inland sea (41°30'-44°S) of north Patagonia, South Pacific, studying a northern basin (NB: Reloncaví Fjord, Reloncaví Sound and Ancud Gulf) characterized by estuarine regime with stronger vertical stratification and warmer (11-14 °C) and most productive waters, and a southern basin (SB: Corcovado Gulf and Guafo mouth), with more oceanic water influence, showed mixed conditions of the water column, colder (11-10.5 °C) and less productive waters. Otolith microstructure and gut content analysis of larval lightfish Maurolicus parvipinnis and rockfish Sebastes oculatus were studied. Larval M. parvipinnis showed similar growth rates in both regions (0.13-0.15 mm d(-1)), but in NB larvae were larger-at-age than in SB. Larval S. oculatus showed no differences in size-at-age and larval growth (0.16 and 0.11 mm d(-1) for NB and SB, respectively). M. parvipinnis larvae from NB had larger number of prey items (mostly invertebrate eggs), similar total volume in their guts and smaller prey size than larvae collected in SB (mainly calanoid copepods). Larval S. oculatus had similar number, volume and body width of prey ingested at both basins, although prey ingestion rate by size was 5 times larger in NB than in SB, and prey composition varied from nauplii in NB to copepodites in SB. This study provides evidence that physical-biological interactions during larval stages of marine fishes from Chilean Patagonia are species-specific, and that in some cases large size-at-age correspond to increasing foraging success. Copyright © 2015 Elsevier Ltd. All rights reserved.

Modelling the Effects of Land-Use Changes on Climate: a Case Study on Yamula DAM

NASA Astrophysics Data System (ADS)

Köylü, Ü.; Geymen, A.

2016-10-01

Dams block flow of rivers and cause artificial water reservoirs which affect the climate and the land use characteristics of the river basin. In this research, the effect of the huge water body obtained by Yamula Dam in Kızılırmak Basin is analysed over surrounding spatial's land use and climate change. Mann Kendal non-parametrical statistical test, Theil&Sen Slope method, Inverse Distance Weighting (IDW), Soil Conservation Service-Curve Number (SCS-CN) methods are integrated for spatial and temporal analysis of the research area. For this research humidity, temperature, wind speed, precipitation observations which are collected in 16 weather stations nearby Kızılırmak Basin are analyzed. After that these statistical information is combined by GIS data over years. An application is developed for GIS analysis in Python Programming Language and integrated with ArcGIS software. Statistical analysis calculated in the R Project for Statistical Computing and integrated with developed application. According to the statistical analysis of extracted time series of meteorological parameters, statistical significant spatiotemporal trends are observed for climate change and land use characteristics. In this study, we indicated the effect of big dams in local climate on semi-arid Yamula Dam.

Hydrocarbon potential assessment of Ngimbang formation, Rihen field of Northeast Java Basin

NASA Astrophysics Data System (ADS)

Pandito, R. H.; Haris, A.; Zainal, R. M.; Riyanto, A.

2017-07-01

The assessment of Ngimbang formation at Rihen field of Northeast Java Basin has been conducted to identify the hydrocarbon potential by analyzing the response of passive seismic on the proven reservoir zone and proposing a tectonic evolution model. In the case of petroleum exploration in Northeast Java basin, the Ngimbang formation cannot be simply overemphasized. East Java Basin has been well known as one of the mature basins producing hydrocarbons in Indonesia. This basin was stratigraphically composed of several formations from the old to the young i.e., the basement, Ngimbang, Kujung, Tuban, Ngerayong, Wonocolo, Kawengan and Lidah formation. All of these formations have proven to become hydrocarbon producer. The Ngrayong formation, which is geologically dominated by channels, has become a production formation. The Kujung formation that has been known with the reef build up has produced more than 102 million barrel of oil. The Ngimbang formation so far has not been comprehensively assessed in term its role as a source rock and a reservoir. In 2013, one exploratory well has been drilled at Ngimbang formation and shown a gas discovery, which is indicated on Drill Stem Test (DST) reading for more than 22 MMSCFD of gas. This discovery opens new prospect in exploring the Ngimbang formation.

Anoxic monimolimnia: Nutrients devious feeders or bombs ready to explode?

NASA Astrophysics Data System (ADS)

Gianni, Areti; Zacharias, Ierotheos

2015-04-01

Coastal regions are under strong human influence and its environmental impact is reflected into their water quality. Oligotrophic estuaries and coastal systems have changed in mesotrophic and/or eutrophic, shown an increase in toxic algal blooms, hypoxic/anoxic events, and massive mortalities of many aquatic and benthic organisms. In strongly stratified and productive water basins, bottom water dissolved oxygen is depleted due to the excessive organic matter decomposition in these depths. Distribution and recycling of nutrients in their water column is inextricably dependent on oxygenation and redox conditions. Bottom water anoxia accelerates PO43-, NH4+ and H2S recycling and accumulation from organic matter decomposition. The anoxic, H2S, PO43- and NH4+ rich bottom water constitutes a toxic layer, threatening the balance of the entire ecosystem. In permanently stratified water basins, storm events could result in stratification destruction and water column total mixing. The turnover brings large amounts of H2S to the surface resulting in low levels of oxygen and massive fish kills. PO43- and NH4+ are released to the interface and surface waters promoting algal blooms. Μore organic matter is produced fueling anoxia. The arising question is, whether the balance of an anoxic water ecosystem is under the threat of its hypolimnetic nutrient and sulfide load, only in the case of storm events and water column total mixing. In polymictic water basins it is clear that the accumulated, in the bottom layer, nutrients will supply surface waters, after the pycnocline overturn. Besides this mechanism of basins' water quality degradation is nowadays recognized as one of the biggest obstacles in eutrophic environments management and restoration efforts. The role of internal load, in permanently stratified water basins, is not so clear. In the present study the impact of storm events on water column stability and bottom water anoxia of meromictic coastal basins, is investigated. The importance of internal load is emerged, presenting the disturbance on the main nutrients, dissolved oxygen, hydrogen sulfide and chlorophyll distribution, caused by the total water column mixing. Additionally, the relationship between temporal nutrients variations in surface layers, of permanent anoxic coastal basins with a) changes on the physicochemical characteristics of their water column, b) changes on the bottom water phosphorus and nitrogen concentration and c) their effect on the basin's primary productivity, is sought. In order to achieve the objectives of this study, two different sets of Aitoliko basin's (western Greece) data were used. The first one includes measurements of physicochemical parameters, nutrients, chlorophyll and hydrogen sulfide, four days after a storm event and the consequent anoxic crisis in Aitoliko basin on 4th of December 2008. The second one contains respective data obtained from a biennial (May 2006-May 2008) basin's monitoring. The changes in the physical, chemical and biological characteristics, of Aitoliko basin water column, after its total mixing, highlighted the importance of the accumulated nutrients and sulfides in the bottom layer. In addition, turned out that bottom layer can supply with nutrients the surface waters, even during periods of high water column stratification. Small scale, subtle, changes in physicochemical and hydrological basin's characteristics promoted this supply, affecting both quantitative and qualitative the ecosystem's primary productivity and shifting its quality character.

Transport of 137Cs and 239,240Pu with ice-rafted debris in the Arctic Ocean

USGS Publications Warehouse

Landa, E.R.; Reimnitz, E.; Beals, D.M.; Pochkowski, J.M.; Winn, W.G.; Rigor, I.

1998-01-01

Ice rafting is the dominant mechanism responsible for the transport of fine-grained sediments from coastal zones to the deep Arctic Basin. Therefore, the drift of ice-rafted debris (IRD) could be a significant transport mechanism from the shelf to the deep basin for radionuclides originating from nuclear fuel cycle activities and released to coastal Arctic regions of the former Soviet Union. In this study, 28 samples of IRD collected from the Arctic ice pack during expeditions in 1989-95 were analyzed for 137Cs by gamma spectrometry and for 239Pu and 240Pu by thermal ionization mass spectrometry. 137Cs concentrations in the IRD ranged from less than 0.2 to 78 Bq??kg-1 (dry weight basis). The two samples with the highest 137Cs concentrations were collected in the vicinity of Franz Josef Land, and their backward trajectories suggest origins in the Kara Sea. Among the lowest 137Cs values are seven measured on sediments entrained on the North American shelf in 1989 and 1995, and sampled on the shelf less than six months later. Concentrations of 239Pu + 240Pu ranged from about 0.02 to 1.8 Bq??kg-1. The two highest values came from samples collected in the central Canada Basin and near Spitsbergen; calculated backward trajectories suggest at least 14 years of circulation in the Canada Basin in the former case, and an origin near Severnaya Zemlya (at the Kara Sea/Laptev Sea boundary) in the latter case. While most of the IRD samples showed 240Pu/239Pu ratios near the mean global fallout value of 0.185, five of the samples had lower ratios, in the 0.119 to 0.166 range, indicative of mixtures of Pu from fallout and from the reprocessing of weapons-grade Pu. The backward trajectories of these five samples suggest origins in the Kara Sea or near Severnaya Zemlya.

Performance of two predictive uncertainty estimation approaches for conceptual Rainfall-Runoff Model: Bayesian Joint Inference and Hydrologic Uncertainty Post-processing

NASA Astrophysics Data System (ADS)

Hernández-López, Mario R.; Romero-Cuéllar, Jonathan; Camilo Múnera-Estrada, Juan; Coccia, Gabriele; Francés, Félix

2017-04-01

It is noticeably important to emphasize the role of uncertainty particularly when the model forecasts are used to support decision-making and water management. This research compares two approaches for the evaluation of the predictive uncertainty in hydrological modeling. First approach is the Bayesian Joint Inference of hydrological and error models. Second approach is carried out through the Model Conditional Processor using the Truncated Normal Distribution in the transformed space. This comparison is focused on the predictive distribution reliability. The case study is applied to two basins included in the Model Parameter Estimation Experiment (MOPEX). These two basins, which have different hydrological complexity, are the French Broad River (North Carolina) and the Guadalupe River (Texas). The results indicate that generally, both approaches are able to provide similar predictive performances. However, the differences between them can arise in basins with complex hydrology (e.g. ephemeral basins). This is because obtained results with Bayesian Joint Inference are strongly dependent on the suitability of the hypothesized error model. Similarly, the results in the case of the Model Conditional Processor are mainly influenced by the selected model of tails or even by the selected full probability distribution model of the data in the real space, and by the definition of the Truncated Normal Distribution in the transformed space. In summary, the different hypotheses that the modeler choose on each of the two approaches are the main cause of the different results. This research also explores a proper combination of both methodologies which could be useful to achieve less biased hydrological parameter estimation. For this approach, firstly the predictive distribution is obtained through the Model Conditional Processor. Secondly, this predictive distribution is used to derive the corresponding additive error model which is employed for the hydrological parameter estimation with the Bayesian Joint Inference methodology.

Chrystal and Proudman resonances simulated with three numerical models

NASA Astrophysics Data System (ADS)

Bubalo, Maja; Janeković, Ivica; Orlić, Mirko

2018-05-01

The aim of this work was to study Chrystal and Proudman resonances in a simple closed basin and to explore and compare how well the two resonant mechanisms are reproduced with different, nowadays widely used, numerical ocean models. The test case was based on air pressure disturbances of two commonly used shapes (a sinusoidal and a boxcar), having various wave lengths, and propagating at different speeds. Our test domain was a closed rectangular basin, 300 km long with a uniform depth of 50 m, with the theoretical analytical solution available for benchmark. In total, 2250 simulations were performed for each of the three different numerical models: ADCIRC, SCHISM and ROMS. During each of the simulations, we recorded water level anomalies and computed the integral of the energy density spectrum for a number of points distributed along the basin. We have successfully documented the transition from Proudman to Chrystal resonance that occurs for a sinusoidal air pressure disturbance having a wavelength between one and two basin lengths. An inter-model comparison of the results shows that different models represent the two resonant phenomena in a slightly different way. For Chrystal resonance, all the models showed similar behavior; however, ADCIRC model providing slightly higher values of the mean resonant period than the other two models. In the case of Proudman resonance, the most consistent results, closest to the analytical solution, were obtained using ROMS model, which reproduced the mean resonant speed equal to 22.00 m/s— i.e., close to the theoretical value of 22.15 m/s. ADCIRC and SCHISM models showed small deviations from that value, with the mean speed being slightly lower—21.97 m/s (ADCIRC) and 21.93 m/s (SCHISM). The findings may seem small but could play an important role when resonance is a crucial process producing enhancing effects by two orders of magnitude (i.e., meteotsunamis).

Distributions, Early Diagenesis, and Spatial Characteristics of Amino Acids in Sediments of Multi-Polluted Rivers: A Case Study in the Haihe River Basin, China.

PubMed

Zhao, Yu; Shan, Baoqing; Tang, Wenzhong; Zhang, Hong; Rong, Nan; Ding, Yuekui

2016-02-19

The Haihe River Basin, which is one of the most water-scarce and polluted river basins in China, has abnormally high nitrogen levels. In this study, total hydrolyzable amino acids (THAAs) were measured in surface sediment and sediment core samples in the Haihe River Basin to determine if amino acids were potential sources of ammonium, organic nitrogen, and organic carbon. The rivers were found to be in a state of hypoxia and contain abnormally high levels of ammonium and organic nitrogen. Additionally, NH₃-N was the predominant form of inorganic nitrogen in the surface sediments, while organic nitrogen accounted for 92.53% of sedimentary nitrogen. THAAs-C accounted for 14.92% of the total organic carbon, while THAAs-N accounted for more than 49.59% of organic nitrogen and 45.68% of total nitrogen. The major fraction of THAAs were protein amino acids. Three sediment cores of the most heavily polluted rivers also showed high levels of THAAs. Evaluation of the degradation index (DI) of sedimentary organic matter in sediments evaluated based on the THAAs revealed that most positive DI values were found in the downstream portion of the Ziya River Watershed. Additionally, the DI of surface sediment was correlated with THAAs (r² = 0.763, p < 0.001), as was the DI of sediment cores (r² = 0.773, p < 0.001). Overall, amino acids in sediments were found to be an important potential source of ammonium, organic nitrogen, and organic carbon.

Nitrate source identification in groundwater of multiple land-use areas by combining isotopes and multivariate statistical analysis: A case study of Asopos basin (Central Greece).

PubMed

Matiatos, Ioannis

2016-01-15

Nitrate (NO3) is one of the most common contaminants in aquatic environments and groundwater. Nitrate concentrations and environmental isotope data (δ(15)N-NO3 and δ(18)O-NO3) from groundwater of Asopos basin, which has different land-use types, i.e., a large number of industries (e.g., textile, metal processing, food, fertilizers, paint), urban and agricultural areas and livestock breeding facilities, were analyzed to identify the nitrate sources of water contamination and N-biogeochemical transformations. A Bayesian isotope mixing model (SIAR) and multivariate statistical analysis of hydrochemical data were used to estimate the proportional contribution of different NO3 sources and to identify the dominant factors controlling the nitrate content of the groundwater in the region. The comparison of SIAR and Principal Component Analysis showed that wastes originating from urban and industrial zones of the basin are mainly responsible for nitrate contamination of groundwater in these areas. Agricultural fertilizers and manure likely contribute to groundwater contamination away from urban fabric and industrial land-use areas. Soil contribution to nitrate contamination due to organic matter is higher in the south-western part of the area far from the industries and the urban settlements. The present study aims to highlight the use of environmental isotopes combined with multivariate statistical analysis in locating sources of nitrate contamination in groundwater leading to a more effective planning of environmental measures and remediation strategies in river basins and water bodies as defined by the European Water Frame Directive (Directive 2000/60/EC).

Distributions, Early Diagenesis, and Spatial Characteristics of Amino Acids in Sediments of Multi-Polluted Rivers: A Case Study in the Haihe River Basin, China

PubMed Central

Zhao, Yu; Shan, Baoqing; Tang, Wenzhong; Zhang, Hong; Rong, Nan; Ding, Yuekui

2016-01-01

The Haihe River Basin, which is one of the most water-scarce and polluted river basins in China, has abnormally high nitrogen levels. In this study, total hydrolyzable amino acids (THAAs) were measured in surface sediment and sediment core samples in the Haihe River Basin to determine if amino acids were potential sources of ammonium, organic nitrogen, and organic carbon. The rivers were found to be in a state of hypoxia and contain abnormally high levels of ammonium and organic nitrogen. Additionally, NH3-N was the predominant form of inorganic nitrogen in the surface sediments, while organic nitrogen accounted for 92.53% of sedimentary nitrogen. THAAs-C accounted for 14.92% of the total organic carbon, while THAAs-N accounted for more than 49.59% of organic nitrogen and 45.68% of total nitrogen. The major fraction of THAAs were protein amino acids. Three sediment cores of the most heavily polluted rivers also showed high levels of THAAs. Evaluation of the degradation index (DI) of sedimentary organic matter in sediments evaluated based on the THAAs revealed that most positive DI values were found in the downstream portion of the Ziya River Watershed. Additionally, the DI of surface sediment was correlated with THAAs (r2 = 0.763, p < 0.001), as was the DI of sediment cores (r2 = 0.773, p < 0.001). Overall, amino acids in sediments were found to be an important potential source of ammonium, organic nitrogen, and organic carbon. PMID:26907310

Bedload Rating and Flow Competence Curves Vary With Watershed and Bed Material Parameters

NASA Astrophysics Data System (ADS)

Bunte, K.; Abt, S. R.

2003-12-01

Bedload transport rating curves and flow competence curves (largest bedload size for specified flow) are usually not known for streams unless a large number of bedload samples has been collected and analyzed. However, this information is necessary for assessing instream flow needs and stream responses to watershed effects. This study therefore analyzed whether bedload transport rating and flow competence curves were related to stream parameters. Bedload transport rating curves and flow competence curves were obtained from extensive bedload sampling in six gravel- and cobble-bed mountain streams. Samples were collected using bedload traps and a large net sampler, both of which provide steep and relatively well-defined bedload rating and flow competence curves due to a long sampling duration, a large sampler opening and a large sampler capacity. The sampled streams have snowmelt regimes, steep (1-9%) gradients, and watersheds that are mainly forested and relatively undisturbed with basin area sizes of 8 to 105 km2. The channels are slightly incised and can contain flows of more than 1.5 times bankfull with little overbank flow. Exponents of bedload rating and flow competence curves obtained from these measurements were found to systematically increase with basin area size and decrease with the degree of channel armoring. By contrast, coefficients of bedload rating and flow competence curves decreased with basin size and increased with armoring. All of these relationships were well-defined (0.86 < r2 < 0.99). Data sets from other studies in coarse-bedded streams fit the indicated trend if the sampling device used allows measuring bedload transport rates over a wide range and if bedload supply is somewhat low. The existence of a general positive trend between bedload rating curve exponents and basin area, and a negative trend between coefficients and basin area, is confirmed by a large data set of bedload rating curves obtained from Helley-Smith samples. However, in this case, the trends only become visible as basin area sizes span a wide range (1 - 10,000 km2). The well-defined relationships obtained from the bedload trap and the large net sampler suggest that exponents and coefficients of bedload transport rating curves (and flow competence curves) are predictable from an easily obtainable parameter such as basin size. However, the relationships of bedload rating curve exponents and coefficients with basin size and armoring appear to be influenced by the sampling device used and the watershed sediment production.

A Systems Approach to Identifying Exploration and Development Opportunities in the Illinois Basin: Digital Portifolio of Plays in Underexplored Lower Paleozoic Rocks [Part 1 of 2

DOE Office of Scientific and Technical Information (OSTI.GOV)

Seyler, Beverly; Harris, David; Keith, Brian

2008-06-30

This study examined petroleum occurrence in Ordovician, Silurian and Devonian reservoirs in the Illinois Basin. Results from this project show that there is excellent potential for additional discovery of petroleum reservoirs in these formations. Numerous exploration targets and exploration strategies were identified that can be used to increase production from these underexplored strata. Some of the challenges to exploration of deeper strata include the lack of subsurface data, lack of understanding of regional facies changes, lack of understanding the role of diagenetic alteration in developing reservoir porosity and permeability, the shifting of structural closures with depth, overlooking potential producing horizons,more » and under utilization of 3D seismic techniques. This study has shown many areas are prospective for additional discoveries in lower Paleozoic strata in the Illinois Basin. This project implemented a systematic basin analysis approach that is expected to encourage exploration for petroleum in lower Paleozoic rocks of the Illinois Basin. The study has compiled and presented a broad base of information and knowledge needed by independent oil companies to pursue the development of exploration prospects in overlooked, deeper play horizons in the Illinois Basin. Available geologic data relevant for the exploration and development of petroleum reservoirs in the Illinois Basin was analyzed and assimilated into a coherent, easily accessible digital play portfolio. The primary focus of this project was on case studies of existing reservoirs in Devonian, Silurian, and Ordovician strata and the application of knowledge gained to future exploration and development in these underexplored strata of the Illinois Basin. In addition, a review of published reports and exploration in the New Albany Shale Group, a Devonian black shale source rock, in Illinois was completed due to the recent increased interest in Devonian black shales across the United States. The New Albany Shale is regarded as the source rock for petroleum in Silurian and younger strata in the Illinois Basin and has potential as a petroleum reservoir. Field studies of reservoirs in Devonian strata such as the Geneva Dolomite, Dutch Creek Sandstone and Grassy knob Chert suggest that there is much additional potential for expanding these plays beyond their current limits. These studies also suggest the potential for the discovery of additional plays using stratigraphic concepts to develop a subcrop play on the subkaskaskia unconformity boundary that separates lower Devonian strata from middle Devonian strata in portions of the basin. The lateral transition from Geneva Dolomite to Dutch Creek Sandstone also offers an avenue for developing exploration strategies in middle Devonian strata. Study of lower Devonian strata in the Sesser Oil Field and the region surrounding the field shows opportunities for development of a subcrop play where lower Devonian strata unconformably overlie Silurian strata. Field studies of Silurian reservoirs along the Sangamon Arch show that opportunities exist for overlooked pays in areas where wells do not penetrate deep enough to test all reservoir intervals in Niagaran rocks. Mapping of Silurian reservoirs in the Mt. Auburn trend along the Sangamon Arch shows that porous reservoir rock grades laterally to non-reservoir facies and several reservoir intervals may be encountered in the Silurian with numerous exploration wells testing only the uppermost reservoir intervals. Mapping of the Ordovician Trenton and shallower strata at Centralia Field show that the crest of the anticline shifted through geologic time. This study illustrates that the axes of anticlines may shift with depth and shallow structure maps may not accurately predict structurally favorable reservoir locations at depth.« less

Assessing the Costs and Benefits of Resilience Investments: Tennessee Valley Authority Case Study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Allen, Melissa R.; Wilbanks, Thomas J.; Preston, Benjamin L.

This report describes a general approach for assessing climate change vulnerabilities of an electricity system and evaluating the costs and benefits of certain investments that would increase system resilience. It uses Tennessee Valley Authority (TVA) as a case study, concentrating on the Cumberland River basin area on the northern side of the TVA region. The study focuses in particular on evaluating risks associated with extreme heat wave and drought conditions that could be expected to affect the region by mid-century. Extreme climate event scenarios were developed using a combination of dynamically downscaled output from the Community Earth System Model andmore » historical heat wave and drought conditions in 1993 and 2007, respectively.« less

Land-use effects on erosion, sediment yields, and reservoir sedimentation: a case study in the Lago Loiza Basin, Puerto Rico

USGS Publications Warehouse

Gellis, A.C.; Webb, R.M.T.; McIntyre, S.C.; Wolfe, W.J.

2006-01-01

 Lago Loíza impounded in 1953 to supply San Juan, Puerto Rico, with drinking water; by 1994, it had lost 47% of its capacity. To characterize sedimentation in Lago Loíza, a study combining land-use history, hillslope erosion rates, and subbasin sediment yields was conducted. Sedimentation rates during the early part of the reservoir’s operation (1953– 1963) were slightly higher than the rates during 1964–1990. In the early history of the reservoir, cropland comprised 48% of the basin and erosion rates were high. Following economic shifts during the 1960s, cropland was abandoned and replaced by forest, which increased from 7.6% in 1950 to 20.6% in 1987. These land-use changes follow a pattern similar to the northeastern United States. Population in the Lago Loíza Basin increased 77% from 1950 to 1990, and housing units increased 194%. Sheetwash erosion measured from 1991 to 1993 showed construction sites had the highest sediment concentration (61,400 ppm), followed by cropland (47,400 ppm), pasture (3510 ppm), and forest (2050 ppm). This study illustrates how a variety of tools and approaches can be used to understand the complex interaction between land use, upland erosion, fluvial sediment transport and storage, and reservoir sedimentation. 

Sediment Transportation Induced by Deep-Seated Landslides in a Debris Flow Basin in Taiwan

NASA Astrophysics Data System (ADS)

Lin, Meei Ling; Chen, Te Wei; Chen, Yong Sheng; Sin Jhuang, Han

2016-04-01

Typhoon Morakot brought huge amount of rainfall to the southern Taiwan in 2009 and caused severe landslides and debris flow hazard. After Typhoon Morakot, it was found that the volume of sediment transported by the debris flow and its effects on the affected area were much more significant compared to previous case history, which may due to the huge amount of rainfall causing significant deep-seated landslides in the basin. In this study, the effects and tendency of the sediment transportation in a river basin following deep-seated landslides caused by typhoon Morakot were evaluated. We used LiDAR, DEM, and aerial photo to identify characteristics of deep-seated landslides in a debris flow river basin, KSDF079 in Liuoguey District, Kaohsiung City, Taiwan. Eight deep-seated landslides were identified in the basin. To estimate the potential landslide volume associated with the deep-seated landslides, the stability analysis was conducted to locate the critical sliding surface, and the potential landside volume was estimated based on the estimation equation proposed by the International Geotechnical Societies' UNESCO Working Party on World Landslide Inventory (WP/WLI, 1990). The total potential landslide volume of the eight deep-seated landslides in KSDF079 basin was about 28,906,856 m3. Topographic analysis was performed by using DEM before and LiDAR derived DEM after typhoon Morakot to calculate the landslide volume transported. The result of erosion volume and deposition volume lead to a run out volume of 5,832,433 m3. The results appeared to consist well with the field condition and aerial photo. Comparing the potential landslide volume and run out volume of eight deep-seated landslides, it was found that the remaining potential landslide volume was about 80%. Field investigation and topographic analysis of the KSDF079 debris flow revealed that a significant amount of sediment deposition remained in the river channel ranging from the middle to the downstream section of the channel, and the channel has been widen. Such large proportion of landslide volume remained in the basin on deep-seated landslide scars and debris flow river channel would likely to cause further debris transportation in the future events. The stability analysis used in this study provided a feasible method and satisfactory results for estimating sediment volume transportation associated with the deep-seated landslides in the study area. Combination of the stability analysis results and the topographic analysis provided estimation of sediment transportation caused by the deep-seated landslides, and trend variation of further sediment transport of the basin, which could provide vital information for hazard mitigation. Keyword: deep-seated landslide, sediment transport, DEM, LiDAR, stability analysis

Hydrological Retrospective of floods and droughts: Case study in the Amazon

NASA Astrophysics Data System (ADS)

Wongchuig Correa, Sly; Cauduro Dias de Paiva, Rodrigo; Carlo Espinoza Villar, Jhan; Collischonn, Walter

2017-04-01

Recent studies have reported an increase in intensity and frequency of hydrological extreme events in many regions of the Amazon basin over last decades, these events such as seasonal floods and droughts have originated a significant impact in human and natural systems. Recently, methodologies such as climatic reanalysis are being developed in order to create a coherent register of climatic systems, thus taking this notion, this research efforts to produce a methodology called Hydrological Retrospective (HR), that essentially simulate large rainfall datasets over hydrological models in order to develop a record over past hydrology, enabling the analysis of past floods and droughts. We developed our methodology on the Amazon basin, thus we used eight large precipitation datasets (more than 30 years) through a large scale hydrological and hydrodynamic model (MGB-IPH), after that HR products were validated against several in situ discharge gauges dispersed throughout Amazon basin, given focus in maximum and minimum events. For better HR results according performance metrics, we performed a forecast skill of HR to detect floods and droughts considering in-situ observations. Furthermore, statistical temporal series trend was performed for intensity of seasonal floods and drought in the whole Amazon basin. Results indicate that better HR represented well most past extreme events registered by in-situ observed data and also showed coherent with many events cited by literature, thus we consider viable to use some large precipitation datasets as climatic reanalysis mainly based on land surface component and datasets based in merged products for represent past regional hydrology and seasonal hydrological extreme events. On the other hand, an increase trend of intensity was realized for maximum annual discharges (related to floods) in north-western regions and for minimum annual discharges (related to drought) in central-south regions of the Amazon basin, these features were previously detected by other researches. In the whole basin, we estimated an upward trend of maximum annual discharges at Amazon River. In order to estimate better future hydrological behavior and their impacts on the society, HR could be used as a methodology to understand past extreme events occurrence in many places considering the global coverage of rainfall datasets.

Spatial and temporal characteristics of droughts in Luanhe River basin, China

NASA Astrophysics Data System (ADS)

Wang, Yixuan; Zhang, Ting; Chen, Xu; Li, Jianzhu; Feng, Ping

2018-02-01

The spatial and temporal characteristics of drought are investigated for Luanhe River basin, using monthly precipitation data from 26 stations covering the common period of 1958-2011. The spatial pattern of drought was assessed by applying principal component analysis (PCA) to the Standardized Precipitation Index (SPI) computed on 3- and 12-month time scales. In addition, annual SPI and seasonal SPIs (including spring SPI, summer SPI, autumn SPI, and winter SPI) were also defined and considered in this study to characterize seasonal and annual drought conditions, respectively. For all seven SPI cases, three distinctive sub-regions with different temporal evolutions of droughts are well identified, respectively, representing the southeast, middle, and northwest of the Luanhe River basin. The Mann-Kendall (MK) trend test with a trend-free pre-whitening (TFPW) procedure and Sen's method were used to determine the temporal trends in the annual and seasonal SPI time series. The continuous wavelet transform (CWT) was employed for further detecting the periodical features of drought condition in each sub-region. Results of MK and Sen's tests show a general tendency of intensification in summer drought over the entire basin, while a significant mitigating trend in spring drought. On the whole, an aggravating trend of inter-annual drought is discovered across the basin. Based on the CWT, the drought variability in the basin is generally dominated by 16- to 64-month cycles, and the 2- to 6-year cycles appear to be obvious when concerned with annual and seasonal droughts. Furthermore, a cross wavelet analysis was performed to examine the possible links between the drought conditions and large-scale climate patterns. The teleconnections of ENSO, NAO, PDO, and AMO show significant influences on the regional droughts principally concentrated in the 16- to 64-month period, maybe responsible for the physical causes of the cyclical behavior of drought occurrences. PDO and AMO also highlight a noteworthy correlation with drought variability on a decadal scale (around 128-month period). The findings of this study will provide valuable references for regional drought mitigation and water resource management.

Case Study: Sensitivity Analysis of the Barataria Basin Barrier Shoreline Wetland Value Assessment Model

DTIC Science & Technology

2014-07-01

wetlands in providing resting, foraging , breeding, and nursery habitat to a diverse assemblage of fish and wildlife species in coastal Louisiana (EWG...services, including fish and wildlife production, storm damage reduction, and recreation. Federal, state, and local partners have jointly pursued large...habitat units” (HU) provided by a given alternative. Whereas traditional HEP models focused on specific taxa, WVA assesses the fish and wildlife community

Detecting changes in riparian habitat conditions based on patterns of greenness change: a case study from the upper San Pedro River Basin, USA

Treesearch

K. Bruce Jones; Curtis E. Edmonds; E. Terrance Slonecker; James D. Wickham; Anne C. Neale; Timothy G. Wade; Kurt H. Riitters; William G. Kepner

2008-01-01

Healthy riparian ecosystems in arid and semi-arid regions exhibit shifting patterns of vegetation in response to periodic flooding. Their conditions also depend upon the amount of grazing and other human uses. Taking advantage of these system properties, we developed and tested an approach that utilizes historical Landsat data to track changes in the patterns...