Thomas A. Kursar; Bettina M. J. Engelbrecht; Melvin T. Tyree
2005-01-01
Plant productivity, distribution and diversity in tropical rain forests correlate with water availability. Water availability is determined by rainfall and also by the available water capacity of the soil. However, while rainfall is recognized as important, linkages between plant distribution and differences among soils in available water capacity have not been...
NASA Astrophysics Data System (ADS)
Juniati, A. T.; Sutjiningsih, D.; Soeryantono, H.; Kusratmoko, E.
2018-01-01
The water availability (WA) of a region is one of important consideration in both the formulation of spatial plans and the evaluation of the effectiveness of actual land use in providing sustainable water resources. Information on land-water needs vis-a-vis their availability in a region determines the state of the surplus or deficit to inform effective land use utilization. How to calculate water availability have been described in the Guideline in Determining the Carrying Capacity of the Environment in Regional Spatial Planning. However, the method of determining the supply and demand of water on these guidelines is debatable since the determination of WA in this guideline used a rational method. The rational method is developed the basis for storm drain design practice and it is essentially a peak discharge method peak discharge calculation method. This paper review the literature in methods of water availability estimation which is described descriptively, and present arguments to claim that water balance method is a more fundamental and appropriate tool in water availability estimation. A better water availability estimation method would serve to improve the practice in preparing formulations of Regional Spatial Plan (RSP) as well as evaluating land use capacity in providing sustainable water resources.
Unravelling the limits to tree height: a major role for water and nutrient trade-offs.
Cramer, Michael D
2012-05-01
Competition for light has driven forest trees to grow exceedingly tall, but the lack of a single universal limit to tree height indicates multiple interacting environmental limitations. Because soil nutrient availability is determined by both nutrient concentrations and soil water, water and nutrient availabilities may interact in determining realised nutrient availability and consequently tree height. In SW Australia, which is characterised by nutrient impoverished soils that support some of the world's tallest forests, total [P] and water availability were independently correlated with tree height (r = 0.42 and 0.39, respectively). However, interactions between water availability and each of total [P], pH and [Mg] contributed to a multiple linear regression model of tree height (r = 0.72). A boosted regression tree model showed that maximum tree height was correlated with water availability (24%), followed by soil properties including total P (11%), Mg (10%) and total N (9%), amongst others, and that there was an interaction between water availability and total [P] in determining maximum tree height. These interactions indicated a trade-off between water and P availability in determining maximum tree height in SW Australia. This is enabled by a species assemblage capable of growing tall and surviving (some) disturbances. The mechanism for this trade-off is suggested to be through water enabling mass-flow and diffusive mobility of P, particularly of relatively mobile organic P, although water interactions with microbial activity could also play a role.
Sandra J. Bucci; Fabian G. Scholz; Guillermo Goldstein; Frederick C. Meinzer; Maria E. Arce
2009-01-01
We studied the water economy of nine woody species differing in rooting depth in a Patagonian shrub steppe from southern Argentina to understand how soil water availability and rooting depth determine their hydraulic architecture. Soil water content and potentials, leaf water potentials (Leaf) hydraulic conductivity, wood density (Pw), rooting depth, and specific leaf...
Key issues for determining the exploitable water resources in a Mediterranean river basin.
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.
Country-level assessment of future risk of water scarcity in Europe
NASA Astrophysics Data System (ADS)
Garrote, Luis; Iglesias, Ana; Granados, Alfredo
2018-06-01
A methodology for regional assessment of current and future water availability in Europe is presented in this study. The methodology is based on a proposed indicator of risk of water scarcity based on the projections of runoff and water availability for European countries. The risk of water scarcity is the combined result of hydrological processes, which determine streamflow in natural conditions, and human intervention, which determines water management using the available hydraulic infrastructure and establishes water supply conditions through operating rules. Model results show that changes in runoff and availability obtained for individual GCM projections can be large and even contradictory. These heterogeneous results are summarized in the water scarcity risk index, a global value that accounts for the results obtained with the ensemble of model results and emission scenarios. The countries at larger risk are (in this order) Spain, Portugal, Macedonia, Greece, Bulgaria, Albania, France and Italy. They are mostly Mediterranean countries already exposed to significant water scarcity problems. There are countries, like Slovakia, Ireland, Belgium, Luxembourg, Croatia and Romania, with mild risk. Northern Arctic countries, like Sweden, Finland, Norway and Russia, show a robust however mild increase in water availability.
THE NEED FOR SPEED-RAPID METHODOLOGIES TO DETERMINE BATHING BEACH WATER QUALITY
Current methods for determining fecal contamination of recreational waters rely on the culture of bacterial indicators and require at least 24 hours to determine whether the water is unsafe for use. By the time monitoring results are available, exposures have already occurred. N...
The role of reservoir storage in large-scale surface water availability analysis for Europe
NASA Astrophysics Data System (ADS)
Garrote, L. M.; Granados, A.; Martin-Carrasco, F.; Iglesias, A.
2017-12-01
A regional assessment of current and future water availability in Europe is presented in this study. The assessment was made using the Water Availability and Adaptation Policy Analysis (WAAPA) model. The model was built on the river network derived from the Hydro1K digital elevation maps, including all major river basins of Europe. Reservoir storage volume was taken from the World Register of Dams of ICOLD, including all dams with storage capacity over 5 hm3. Potential Water Availability is defined as the maximum amount of water that could be supplied at a certain point of the river network to satisfy a regular demand under pre-specified reliability requirements. Water availability is the combined result of hydrological processes, which determine streamflow in natural conditions, and human intervention, which determines the available hydraulic infrastructure to manage water and establishes water supply conditions through operating rules. The WAAPA algorithm estimates the maximum demand that can be supplied at every node of the river network accounting for the regulation capacity of reservoirs under different management scenarios. The model was run for a set of hydrologic scenarios taken from the Inter-Sectoral Impact Model Intercomparison Project (ISIMIP), where the PCRGLOBWB hydrological model was forced with results from five global climate models. Model results allow the estimation of potential water stress by comparing water availability to projections of water abstractions along the river network under different management alternatives. The set of sensitivity analyses performed showed the effect of policy alternatives on water availability and highlighted the large uncertainties linked to hydrological and anthropological processes.
NASA Astrophysics Data System (ADS)
Lissner, Tabea; Reusser, Dominik
2015-04-01
Inadequate access to water is already a problem in many regions of the world and processes of global change are expected to further exacerbate the situation. Many aspects determine the adequacy of water resources: beside actual physical water stress, where the resource itself is limited, economic and social water stress can be experienced if access to resource is limited by inadequate infrastructure, political or financial constraints. To assess the adequacy of water availability for human use, integrated approaches are needed that allow to view the multiple determinants in conjunction and provide sound results as a basis for informed decisions. This contribution proposes two parts of an integrated approach to look at the multiple dimensions of water scarcity at regional to global scale. These were developed in a joint project with the German Development Agency (GIZ). It first outlines the AHEAD approach to measure Adequate Human livelihood conditions for wEll-being And Development, implemented at global scale and at national resolution. This first approach allows viewing impacts of climate change, e.g. changes in water availability, within the wider context of AHEAD conditions. A specific focus lies on the uncertainties in projections of climate change and future water availability. As adequate water access is not determined by water availability alone, in a second step we develop an approach to assess the water requirements for different sectors in more detail, including aspects of quantity, quality as well as access, in an integrated way. This more detailed approach is exemplified at region-scale in Indonesia and South Africa. Our results show that in many regions of the world, water scarcity is a limitation to AHEAD conditions in many countries, regardless of differing modelling output. The more detailed assessments highlight the relevance of additional aspects to assess the adequacy of water for human use, showing that in many regions, quality and infrastructure are the main limitations to water security.
Tarroja, Brian; AghaKouchak, Amir; Sobhani, Reza; Feldman, David; Jiang, Sunny; Samuelsen, Scott
2014-11-01
The technical potential and effectiveness of different water supply options for securing water availability in a large-scale, interconnected water supply system under historical and climate-change augmented inflow and demand conditions were compared. Part 1 of the study focused on determining the scale of the options required to secure water availability and compared the effectiveness of different options. A spatially and temporally resolved model of California's major surface reservoirs was developed, and its sensitivity to urban water conservation, desalination, and water reuse was examined. Potential capacities of the different options were determined. Under historical (baseline) hydrology conditions, many individual options were found to be capable of securing water availability alone. Under climate change augment conditions, a portfolio approach was necessary. The water savings from many individual options other than desalination were insufficient in the latter, however, relying on seawater desalination alone requires extreme capacity installations which have energy, brine disposal, management, and cost implications. The importance of identifying and utilizing points of leverage in the system for choosing where to deploy different options is also demonstrated. Copyright © 2014 Elsevier B.V. All rights reserved.
Plant roots use a patterning mechanism to position lateral root branches toward available water.
Bao, Yun; Aggarwal, Pooja; Robbins, Neil E; Sturrock, Craig J; Thompson, Mark C; Tan, Han Qi; Tham, Cliff; Duan, Lina; Rodriguez, Pedro L; Vernoux, Teva; Mooney, Sacha J; Bennett, Malcolm J; Dinneny, José R
2014-06-24
The architecture of the branched root system of plants is a major determinant of vigor. Water availability is known to impact root physiology and growth; however, the spatial scale at which this stimulus influences root architecture is poorly understood. Here we reveal that differences in the availability of water across the circumferential axis of the root create spatial cues that determine the position of lateral root branches. We show that roots of several plant species can distinguish between a wet surface and air environments and that this also impacts the patterning of root hairs, anthocyanins, and aerenchyma in a phenomenon we describe as hydropatterning. This environmental response is distinct from a touch response and requires available water to induce lateral roots along a contacted surface. X-ray microscale computed tomography and 3D reconstruction of soil-grown root systems demonstrate that such responses also occur under physiologically relevant conditions. Using early-stage lateral root markers, we show that hydropatterning acts before the initiation stage and likely determines the circumferential position at which lateral root founder cells are specified. Hydropatterning is independent of endogenous abscisic acid signaling, distinguishing it from a classic water-stress response. Higher water availability induces the biosynthesis and transport of the lateral root-inductive signal auxin through local regulation of tryptophan aminotransferase of Arabidopsis 1 and PIN-formed 3, both of which are necessary for normal hydropatterning. Our work suggests that water availability is sensed and interpreted at the suborgan level and locally patterns a wide variety of developmental processes in the root.
18 CFR 806.12 - Constant-rate aquifer testing.
Code of Federal Regulations, 2010 CFR
2010-04-01
... groundwater availability analysis to determine the availability of water during a 1-in-10-year recurrence... 18 Conservation of Power and Water Resources 2 2010-04-01 2010-04-01 false Constant-rate aquifer testing. 806.12 Section 806.12 Conservation of Power and Water Resources SUSQUEHANNA RIVER BASIN...
Current methods for determining fecal contamination of recreational waters rely on the culture of bacterial indicators and require at least 24 hours to determine whether the water is unsafe for use. By the time monitoring results are available, exposures have already occurred. N...
NASA Astrophysics Data System (ADS)
Riccardi, Maria; Alfieri, Silvia Maria; Basile, Angelo; Bonfante, Antonello; Menenti, Massimo; Monaco, Eugenia; De Lorenzi, Francesca
2013-04-01
Climate evolution, with the foreseen increase of temperature and frequency of drought events during the summer, could cause significant changes in the availability of water resources specially in the Mediterranean region. European countries need to encourage sustainable agriculture practices, reducing inputs, especially of water, and minimizing any negative impact on crop quantity and quality. Olive is an important crop in the Mediterranean region that has traditionally been cultivated with no irrigation and is known to attain acceptable production under dry farming. Therefore this crop will not compete for foreseen reduced water resources. However, a good quantitative knowledge must be available about effects of reduced precipitation and water availability on yield. Yield response functions, coupled with indicators of soil water availability, provide a quantitative description of the cultivar- specific behavior in relation to hydrological conditions. Yield response functions of 11 olive cultivars, typical of Mediterranean environment, were determined using experimental data (unpublished or reported in scientific literature). The yield was expressed as relative yield (Yr); the soil water availability was described by means of different indicators: relative soil water deficit (RSWD), relative evapotranspiration (RED) and transpiration deficit (RTD). Crops can respond nonlinearly to changes in their growing conditions and exhibit threshold responses, so for the yield functions of each olive cultivar both linear regression and threshold-slope models were considered to evaluate the best fit. The level of relative yield attained in rain-fed conditions was identified and defined as the acceptable yield level (Yrrainfed). The value of the indicator (RSWD, RED and RTD) corresponding to Yrrainfed was determined for each cultivar and indicated as the critical value of water availability. The error in the determination of the critical value was estimated. By means of a simulation model of the water flow in the soil-plant-atmosphere system, the indicators of soil water availability were calculated for different soil units in an area of Southern Italy, traditionally cultivated with olive. Simulations were performed for two climate scenarios: reference (1961-90) and future climate (2021-50). The potentiality of the indicators RSWD, RED and RTD to describe soil water availability was evaluated using simulated and experimental data. The analysis showed that RED values were correlated to RTD. The analysis demonstrated that RTD was more effective than RED in representing crop water availability RSWD is very well correlated to RTD and the degree of correlation depends of the period of deficit considered. The probability of adaptation of each cultivar was calculated for both climatic periods by comparing the critical values (and their error distribution) with soil availability indicators. Keywords: Olea europaea, soil water deficit, water availability critical value. The work was carried out within the Italian national project AGROSCENARI funded by the Ministry for Agricultural, Food and Forest Policies (MIPAAF, D.M. 8608/7303/2008)
18 CFR 701.207 - Extension of time limits for WRC initial and final determinations.
Code of Federal Regulations, 2012 CFR
2012-04-01
... 18 Conservation of Power and Water Resources 2 2012-04-01 2012-04-01 false Extension of time limits for WRC initial and final determinations. 701.207 Section 701.207 Conservation of Power and Water Resources WATER RESOURCES COUNCIL COUNCIL ORGANIZATION Availability of Information § 701.207 Extension of...
18 CFR 701.205 - Time limit for requester to appeal an initial adverse determination.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 18 Conservation of Power and Water Resources 2 2010-04-01 2010-04-01 false Time limit for requester to appeal an initial adverse determination. 701.205 Section 701.205 Conservation of Power and Water Resources WATER RESOURCES COUNCIL COUNCIL ORGANIZATION Availability of Information § 701.205 Time...
18 CFR 701.204 - Time limits for WRC initial determinations regarding requests for information.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 18 Conservation of Power and Water Resources 2 2010-04-01 2010-04-01 false Time limits for WRC initial determinations regarding requests for information. 701.204 Section 701.204 Conservation of Power and Water Resources WATER RESOURCES COUNCIL COUNCIL ORGANIZATION Availability of Information § 701.204...
18 CFR 701.207 - Extension of time limits for WRC initial and final determinations.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 18 Conservation of Power and Water Resources 2 2011-04-01 2011-04-01 false Extension of time limits for WRC initial and final determinations. 701.207 Section 701.207 Conservation of Power and Water Resources WATER RESOURCES COUNCIL COUNCIL ORGANIZATION Availability of Information § 701.207 Extension of...
18 CFR 701.207 - Extension of time limits for WRC initial and final determinations.
Code of Federal Regulations, 2013 CFR
2013-04-01
... 18 Conservation of Power and Water Resources 2 2013-04-01 2012-04-01 true Extension of time limits for WRC initial and final determinations. 701.207 Section 701.207 Conservation of Power and Water Resources WATER RESOURCES COUNCIL COUNCIL ORGANIZATION Availability of Information § 701.207 Extension of...
18 CFR 701.207 - Extension of time limits for WRC initial and final determinations.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 18 Conservation of Power and Water Resources 2 2010-04-01 2010-04-01 false Extension of time limits for WRC initial and final determinations. 701.207 Section 701.207 Conservation of Power and Water Resources WATER RESOURCES COUNCIL COUNCIL ORGANIZATION Availability of Information § 701.207 Extension of...
18 CFR 701.204 - Time limits for WRC initial determinations regarding requests for information.
Code of Federal Regulations, 2012 CFR
2012-04-01
... 18 Conservation of Power and Water Resources 2 2012-04-01 2012-04-01 false Time limits for WRC initial determinations regarding requests for information. 701.204 Section 701.204 Conservation of Power and Water Resources WATER RESOURCES COUNCIL COUNCIL ORGANIZATION Availability of Information § 701.204...
18 CFR 701.205 - Time limit for requester to appeal an initial adverse determination.
Code of Federal Regulations, 2014 CFR
2014-04-01
... 18 Conservation of Power and Water Resources 2 2014-04-01 2014-04-01 false Time limit for requester to appeal an initial adverse determination. 701.205 Section 701.205 Conservation of Power and Water Resources WATER RESOURCES COUNCIL COUNCIL ORGANIZATION Availability of Information § 701.205 Time...
18 CFR 701.204 - Time limits for WRC initial determinations regarding requests for information.
Code of Federal Regulations, 2014 CFR
2014-04-01
... 18 Conservation of Power and Water Resources 2 2014-04-01 2014-04-01 false Time limits for WRC initial determinations regarding requests for information. 701.204 Section 701.204 Conservation of Power and Water Resources WATER RESOURCES COUNCIL COUNCIL ORGANIZATION Availability of Information § 701.204...
18 CFR 701.204 - Time limits for WRC initial determinations regarding requests for information.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 18 Conservation of Power and Water Resources 2 2011-04-01 2011-04-01 false Time limits for WRC initial determinations regarding requests for information. 701.204 Section 701.204 Conservation of Power and Water Resources WATER RESOURCES COUNCIL COUNCIL ORGANIZATION Availability of Information § 701.204...
18 CFR 701.204 - Time limits for WRC initial determinations regarding requests for information.
Code of Federal Regulations, 2013 CFR
2013-04-01
... 18 Conservation of Power and Water Resources 2 2013-04-01 2012-04-01 true Time limits for WRC initial determinations regarding requests for information. 701.204 Section 701.204 Conservation of Power and Water Resources WATER RESOURCES COUNCIL COUNCIL ORGANIZATION Availability of Information § 701.204...
18 CFR 701.207 - Extension of time limits for WRC initial and final determinations.
Code of Federal Regulations, 2014 CFR
2014-04-01
... 18 Conservation of Power and Water Resources 2 2014-04-01 2014-04-01 false Extension of time limits for WRC initial and final determinations. 701.207 Section 701.207 Conservation of Power and Water Resources WATER RESOURCES COUNCIL COUNCIL ORGANIZATION Availability of Information § 701.207 Extension of...
18 CFR 701.205 - Time limit for requester to appeal an initial adverse determination.
Code of Federal Regulations, 2012 CFR
2012-04-01
... 18 Conservation of Power and Water Resources 2 2012-04-01 2012-04-01 false Time limit for requester to appeal an initial adverse determination. 701.205 Section 701.205 Conservation of Power and Water Resources WATER RESOURCES COUNCIL COUNCIL ORGANIZATION Availability of Information § 701.205 Time...
18 CFR 701.205 - Time limit for requester to appeal an initial adverse determination.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 18 Conservation of Power and Water Resources 2 2011-04-01 2011-04-01 false Time limit for requester to appeal an initial adverse determination. 701.205 Section 701.205 Conservation of Power and Water Resources WATER RESOURCES COUNCIL COUNCIL ORGANIZATION Availability of Information § 701.205 Time...
Influence of free water availability on a desert carnivore and herbivore.
Kluever, Bryan M; Gese, Eric M; Dempsey, Steven J
2017-04-01
Anthropogenic manipulation of finite resources on the landscape to benefit individual species or communities is commonly employed by conservation and management agencies. One such action in arid regions is the construction and maintenance of water developments (i.e., wildlife guzzlers) adding free water on the landscape to buttress local populations, influence animal movements, or affect distributions of certain species of interest. Despite their prevalence, the utility of wildlife guzzlers remains largely untested. We employed a before-after control-impact (BACI) design over a 4-year period on the US Army Dugway Proving Ground, Utah, USA, to determine whether water availability at wildlife guzzlers influenced relative abundance of black-tailed jackrabbits Lepus californicus and relative use of areas near that resource by coyotes Canis latrans , and whether coyote visitations to guzzlers would decrease following elimination of water. Eliminating water availability at guzzlers did not influence jackrabbit relative abundance. Coyote relative use was impacted by water availability, with elimination of water reducing use in areas associated with our treatment, but not with areas associated with our control. Visitations of radio-collared coyotes to guzzlers declined nearly 3-fold following elimination of water. Our study provides the first evidence of a potential direct effect of water sources on a mammalian carnivore in an arid environment, but the ecological relevance of our finding is debatable. Future investigations aimed at determining water effects on terrestrial mammals could expand on our findings by incorporating manipulations of water availability, obtaining absolute estimates of population parameters and vital rates and incorporating fine-scale spatiotemporal data.
Influence of free water availability on a desert carnivore and herbivore
Gese, Eric M.; Dempsey, Steven J.
2017-01-01
Abstract Anthropogenic manipulation of finite resources on the landscape to benefit individual species or communities is commonly employed by conservation and management agencies. One such action in arid regions is the construction and maintenance of water developments (i.e., wildlife guzzlers) adding free water on the landscape to buttress local populations, influence animal movements, or affect distributions of certain species of interest. Despite their prevalence, the utility of wildlife guzzlers remains largely untested. We employed a before–after control-impact (BACI) design over a 4-year period on the US Army Dugway Proving Ground, Utah, USA, to determine whether water availability at wildlife guzzlers influenced relative abundance of black-tailed jackrabbits Lepus californicus and relative use of areas near that resource by coyotes Canis latrans, and whether coyote visitations to guzzlers would decrease following elimination of water. Eliminating water availability at guzzlers did not influence jackrabbit relative abundance. Coyote relative use was impacted by water availability, with elimination of water reducing use in areas associated with our treatment, but not with areas associated with our control. Visitations of radio-collared coyotes to guzzlers declined nearly 3-fold following elimination of water. Our study provides the first evidence of a potential direct effect of water sources on a mammalian carnivore in an arid environment, but the ecological relevance of our finding is debatable. Future investigations aimed at determining water effects on terrestrial mammals could expand on our findings by incorporating manipulations of water availability, obtaining absolute estimates of population parameters and vital rates and incorporating fine-scale spatiotemporal data. PMID:29491969
NASA Astrophysics Data System (ADS)
Klise, G. T.; Tidwell, V. C.; Macknick, J.; Reno, M. D.; Moreland, B. D.; Zemlick, K. M.
2013-12-01
In the Southwestern United States, there are many large utility-scale solar photovoltaic (PV) and concentrating solar power (CSP) facilities currently in operation, with even more under construction and planned for future development. These are locations with high solar insolation and access to large metropolitan areas and existing grid infrastructure. The Bureau of Land Management, under a reasonably foreseeable development scenario, projects a total of almost 32 GW of installed utility-scale solar project capacity in the Southwest by 2030. To determine the potential impacts to water resources and the potential limitations water resources may have on development, we utilized methods outlined by the Bureau of Land Management (BLM) to determine potential water use in designated solar energy zones (SEZs) for construction and operations & maintenance (O&M), which is then evaluated according to water availability in six Southwestern states. Our results indicate that PV facilities overall use less water, however water for construction is high compared to lifetime operational water needs. There is a transition underway from wet cooled to dry cooled CSP facilities and larger PV facilities due to water use concerns, though some water is still necessary for construction, operations, and maintenance. Overall, ten watersheds, 9 in California, and one in New Mexico were identified as being of particular concern because of limited water availability. Understanding the location of potentially available water sources can help the solar industry determine locations that minimize impacts to existing water resources, and help understand potential costs when utilizing non-potable water sources or purchasing existing appropriated water. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.
18 CFR 701.205 - Time limit for requester to appeal an initial adverse determination.
Code of Federal Regulations, 2013 CFR
2013-04-01
... 18 Conservation of Power and Water Resources 2 2013-04-01 2012-04-01 true Time limit for requester to appeal an initial adverse determination. 701.205 Section 701.205 Conservation of Power and Water Resources WATER RESOURCES COUNCIL COUNCIL ORGANIZATION Availability of Information § 701.205 Time limit for...
NASA Astrophysics Data System (ADS)
Gunda, T.; Hornberger, G. M.
2017-12-01
Concerns over water resources have evolved over time, from physical availability to economic access and recently, to a more comprehensive study of "water security," which is inherently interdisciplinary because a secure water system is influenced by and affects both physical and social components. The concept of water security carries connotations of both an adequate supply of water as well as water that meets certain quality standards. Although the term "water security" has many interpretations in the literature, the research field has not yet developed a synthetic analysis of water security as both a quantity (availability) and quality (contamination) issue. Using qualitative comparative and multi-regression analyses, we evaluate the primary physical and social factors influencing U.S. states' water security from a quantity perspective and from a quality perspective. Water system characteristics are collated from academic and government sources and include access/use, governance, and sociodemographic, and ecosystem metrics. Our analysis indicates differences in variables driving availability and contamination concerns; for example, climate is a more significant determinant in water quantity-based security analyses than in water quality-based security analyses. We will also discuss coevolution of system traits and the merits of constructing a robust water security index based on the relative importance of metrics from our analyses. These insights will improve understanding of the complex interactions between quantity and quality aspects and thus, overall security of water systems.
Ground-Water Availability in the United States
Reilly, Thomas E.; Dennehy, Kevin F.; Alley, William M.; Cunningham, William L.
2008-01-01
Ground water is among the Nation's most important natural resources. It provides half our drinking water and is essential to the vitality of agriculture and industry, as well as to the health of rivers, wetlands, and estuaries throughout the country. Large-scale development of ground-water resources with accompanying declines in ground-water levels and other effects of pumping has led to concerns about the future availability of ground water to meet domestic, agricultural, industrial, and environmental needs. The challenges in determining ground-water availability are many. This report examines what is known about the Nation's ground-water availability and outlines a program of study by the U.S. Geological Survey Ground-Water Resources Program to improve our understanding of ground-water availability in major aquifers across the Nation. The approach is designed to provide useful regional information for State and local agencies who manage ground-water resources, while providing the building blocks for a national assessment. The report is written for a wide audience interested or involved in the management, protection, and sustainable use of the Nation's water resources.
NASA Astrophysics Data System (ADS)
Post, David
2010-05-01
In a water-scarce country such as Australia, detailed, accurate and reliable assessments of current and future water availability are essential in order to adequately manage the limited water resource. This presentation describes a recently completed study which provided an assessment of current water availability in Tasmania, Australia, and also determined how this water availability would be impacted by climate change and proposed catchment development by the year 2030. The Tasmania Sustainable Yields Project (http://www.csiro.au/partnerships/TasSY.html) assessed current water availability through the application of rainfall-runoff models, river models, and recharge and groundwater models. These were calibrated to streamflow records and parameterised using estimates of current groundwater and surface water extractions and use. Having derived a credible estimate of current water availability, the impacts of future climate change on water availability were determined through deriving changes in rainfall and potential evapotranspiration from 15 IPCC AR4 global climate models. These changes in rainfall were then dynamically downscaled using the CSIRO-CCAM model over the relatively small study area (50,000 square km). A future climate sequence was derived by modifying the historical 84-year climate sequence based on these changes in rainfall and potential evapotranspiration. This future climate sequence was then run through the rainfall-runoff, river, recharge and groundwater models to give an estimate of water availability under future climate. To estimate the impacts of future catchment development on water availability, the models were modified and re-run to reflect projected increases in development. Specifically, outputs from the rainfall-runoff and recharge models were reduced over areas of projected future plantation forestry. Conversely, groundwater recharge was increased over areas of new irrigated agriculture and new extractions of water for irrigation were implemented in the groundwater and river models. Results indicate that historical average water availability across the project area was 21,815 GL/year. Of this, 636 GL/year of surface water and 38 GL/year of groundwater are currently extracted for use. By 2030, rainfall is projected to decrease by an average of 3% over the project area. This decrease in rainfall and concurrent increase in potential evapotranspiration leads to a decrease in water availability of 5% by 2030. As a result of lower streamflows, under current cease-to-take rules, currently licensed extractions are projected to decrease by 3% (19 GL/year). This however is offset by an additional 120 GL/year of extractions for proposed new irrigated agriculture. These new extractions, along with the increase in commercial forest plantations lead to a reduction in total surface water of 1% in addition to the 5% reduction due to climate change. Results from this study are being used by the Tasmanian and Australian governments to guide the development of a sustainable irrigated agriculture industry in Tasmania. In part, this is necessary to offset the loss of irrigated agriculture from the southern Murray-Darling Basin where climate change induced reductions in rainfall are projected to be far worse.
Water resources of the Roseau River Watershed, Northwestern Minnesota
Winter, Thomas C.; Maclay, R.W.; Pike, G.M.
1967-01-01
This report is a general appraisal of the water resources in the Roseau River watershed unit. Detailed studies of water movement through the ground-water reservoir are needed for more exact determination of the amount of water immediately available and the specific effects of water-management practices.
NASA Astrophysics Data System (ADS)
De Lorenzi, F.; Bonfante, A.; Alfieri, S.; Patanè, C.; Basile, A.; Di Tommasi, P.; Monaco, E.; Menenti, M.
2012-04-01
Climate evolution will cause significant changes in the quality and availability of water resources, affecting many sectors including food production, where available water resources for irrigation play a crucial role. Strategies focused on managing and conserving water are one way to deal with the impact; moreover concurring adaptation measurements will be needed to cope with the foreseen decline of water resource. This work deals with i) the impacts of climate change on water requirements of an horticultural crop, determined in an irrigated district in Southern Italy, ii) the possible irrigation scheduling options and their sustainability in the future, iii) the adaptation measurements that can be undertaken to protect production, relying on intra-specific biodiversity of agricultural crops. Two climate scenarios were considered: present climate (1961-90) and future climate (2021-2050), the former from climatic statistics, and the latter from statistical downscaling of general circulation models (AOGCM). Climatic data set consists of daily time series of maximum and minimum temperature, and rainfall on a grid with spatial resolution of 35 km. The analysis of climate scenarios showed that significant increases in summer maximum daily temperature could be expected in 2021-2050 period. Soil water regime was determined by means of a mechanistic model (SWAP) of water flow in the soil-plant-atmosphere system. Twenty? soil units were identified in the district (in Sele Plain, Campania Region) and simulations were performed accounting for hydro-pedological properties of different soil units. Parameters of a generic tomato crop, in a rotation typical of the area, were used in simulations. Soil water balance was simulated in the present and future climate, both with optimal water availability and under constrains that irrigation schemes will pose. Indicators of soil water availability were calculated, in terms of soil water or evapotranspiration deficit. For several tomato cultivars, quantitative yield response functions to water availability were determined through the re-analysis of experimental data, derived from scientific literature. Variety-specific threshold values of yield reduction in dependence of soil water and evapotranspiration deficit were determined. The spatial pattern of soil water availability indicators was calculated., for present and future climate scenarios and for different irrigation scheduling options. Cultivars' threshold values were matched with indicators' values in all soil units. The future adaptability of the crop in the area is thus evaluated, and adaptation options that exploit the intra-specific biodiversity of the crop are indicated. The work was carried out within the Italian national project AGROSCENARI funded by the Ministry for Agricultural, Food and Forest Policies (MIPAAF, D.M. 8608/7303/2008) Keywords: climate change, tomato, deficit irrigation, biodiversity
Evaluating water quality -- is it important, how can it be determined and how can it be used?
NASA Astrophysics Data System (ADS)
Leahy, P. P.
2015-12-01
Freshwater is critical to sustaining all life on Earth yet most humans take this resource for granted and often consider it a free good. However, in water-poor areas, the availability of clean drinking water limits economic development, negatively impacts human health and causes significant social instability. This was a driver for the Millennium Development Goals to include providing clean water to the developing world. Unlike other resources, another commodity cannot be substituted for water. In mineral resources, substitution is common depending on the use, for example, aluminum for steel in automotive bodies. In energy, humans can, in some instances, use natural gas instead of coal for electricity generation. Given the critical nature of freshwater for human existence, it is important that the resource be evaluated in economic terms. Although efforts to assess the value of the availability of freshwater have been developed, they are not commonly used. Water quality is also a major economic factor in availability of water resources. Quality can be prohibitively expensive to bring to acceptable standards and can easily be contaminated by human activities. Determining an economic and social value on both the availability and quality of water resources is a challenge that the hydrologic community must address at local, regional and national and even global scales to support informed policy and decision-making.
Sensible heat balance measurements of soil water evaporation beneath a maize canopy
USDA-ARS?s Scientific Manuscript database
Soil water evaporation is an important component of the water budget in a cropped field. Few methods are available for continuous and independent measurement of soil water evaporation. A sensible heat balance (SHB) approach has recently been demonstrated for continuously determining soil water evapo...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Solander, Kurt C.; Reager, John T.; Wada, Yoshihide
Changes in the climate and population growth will critically impact the future supply and demand of water, leading to large uncertainties for sustainable resource management. In the absence of on-the-ground measurements to provide spatially continuous, high-resolution information on water supplies, satellite observations can provide essential insight. Here, we develop a technique using observations from the Gravity Recovery and Climate Experiment (GRACE) satellite to evaluate the sustainability of surface water and groundwater use over the continental United States. We determine the annual total water availability for 2003–2015 using the annual variability in GRACE-derived total water storage for 18 major watersheds. Themore » long-term sustainable water quantity available to humans is calculated by subtracting an annual estimate of the water needed to maintain local ecosystems, and the resulting water volumes are compared to reported consumptive water use to determine a sustainability fraction. We find over-consumption is highest in the southwest US, where increasing stress trends were observed in all five basins and annual consumptive use exceeded 100% availability twice in the Lower Colorado basin during 2003–2015. By providing a coarse-scale evaluation of sustainable water use from satellite and ground observations, the established framework serves as a blueprint for future large-scale water resource monitoring.« less
Solander, Kurt C.; Reager, John T.; Wada, Yoshihide; ...
2017-08-18
Changes in the climate and population growth will critically impact the future supply and demand of water, leading to large uncertainties for sustainable resource management. In the absence of on-the-ground measurements to provide spatially continuous, high-resolution information on water supplies, satellite observations can provide essential insight. Here, we develop a technique using observations from the Gravity Recovery and Climate Experiment (GRACE) satellite to evaluate the sustainability of surface water and groundwater use over the continental United States. We determine the annual total water availability for 2003–2015 using the annual variability in GRACE-derived total water storage for 18 major watersheds. Themore » long-term sustainable water quantity available to humans is calculated by subtracting an annual estimate of the water needed to maintain local ecosystems, and the resulting water volumes are compared to reported consumptive water use to determine a sustainability fraction. We find over-consumption is highest in the southwest US, where increasing stress trends were observed in all five basins and annual consumptive use exceeded 100% availability twice in the Lower Colorado basin during 2003–2015. By providing a coarse-scale evaluation of sustainable water use from satellite and ground observations, the established framework serves as a blueprint for future large-scale water resource monitoring.« less
An analytical method to determine ground water supply well network designs.
MacMillan, Gordon James
2009-01-01
An analytical method is provided where the ground water practitioner can quickly determine the size (number of wells) and spacing of a well network capable of meeting a known ground water demand. In order to apply the method, two new parameters are derived that relate theoretical drawdown to the maximum drawdown that is achievable without mining the aquifer. The size of a well network is shown to be proportional to the ground water demand and inversely proportional to the transmissivity and available head. The spacing between wells in a supply well network is shown to be most sensitive to a derived parameter r(HA/3) , which is related to the available head and the propagation of drawdown away from a theoretical well if the total ground water demand was applied to that well. The method can be used to quickly determine the required spacing between wells in well networks of various sizes that are completed in confined aquifers with no leakance. Copyright © 2009 The Author(s). Journal Compilation © 2009 National Ground Water Association.
Delaire, Caroline; Das, Abhijit; Amrose, Susan; Gadgil, Ashok; Roy, Joyashree; Ray, Isha
2017-10-01
Shallow groundwater containing toxic concentrations of arsenic is the primary source of drinking water for millions of households in rural West Bengal, India. Often, this water also contains unpleasant levels of iron and non-negligible fecal contamination. Alternatives to shallow groundwater are increasingly available, including government-built deep tubewells, water purchased from independent providers, municipal piped water, and household filters. We conducted a survey of 501 households in Murshidabad district in 2014 to explore what influenced the use of available alternatives. Socioeconomic status and the perceived likelihood of gastrointestinal (GI) illness (which was associated with dissatisfaction with iron in groundwater) were the primary determinants of the use of alternatives. Arsenic knowledge was limited. The choice amongst alternatives was influenced by economic, social, and aesthetic factors, but not by health risk perceptions. The use of purchased water was rarely exclusive and was strongly associated with socioeconomic status, suggesting that this form of market-based water provision does not ensure universal access. Demand for purchased water appeared to decrease significantly shortly after free piped water became available at public taps. Our results suggest that arsenic mitigation interventions that also address co-occurring water problems (iron, GI illness) could be more effective than a focus on arsenic alone.
Cayuela, Luis; González-Caro, Sebastián; Aldana, Ana M.; Stevenson, Pablo R.; Phillips, Oliver; Cogollo, Álvaro; Peñuela, Maria C.; von Hildebrand, Patricio; Jiménez, Eliana; Melo, Omar; Londoño-Vega, Ana Catalina; Mendoza, Irina; Velásquez, Oswaldo; Fernández, Fernando; Serna, Marcela; Velázquez-Rua, Cesar; Benítez, Doris; Rey-Benayas, José M.
2017-01-01
Understanding and predicting the likely response of ecosystems to climate change are crucial challenges for ecology and for conservation biology. Nowhere is this challenge greater than in the tropics as these forests store more than half the total atmospheric carbon stock in their biomass. Biomass is determined by the balance between biomass inputs (i.e., growth) and outputs (mortality). We can expect therefore that conditions that favor high growth rates, such as abundant water supply, warmth, and nutrient-rich soils will tend to correlate with high biomass stocks. Our main objective is to describe the patterns of above ground biomass (AGB) stocks across major tropical forests across climatic gradients in Northwestern South America. We gathered data from 200 plots across the region, at elevations ranging between 0 to 3400 m. We estimated AGB based on allometric equations and values for stem density, basal area, and wood density weighted by basal area at the plot-level. We used two groups of climatic variables, namely mean annual temperature and actual evapotranspiration as surrogates of environmental energy, and annual precipitation, precipitation seasonality, and water availability as surrogates of water availability. We found that AGB is more closely related to water availability variables than to energy variables. In northwest South America, water availability influences carbon stocks principally by determining stand structure, i.e. basal area. When water deficits increase in tropical forests we can expect negative impact on biomass and hence carbon storage. PMID:28301482
Álvarez-Dávila, Esteban; Cayuela, Luis; González-Caro, Sebastián; Aldana, Ana M; Stevenson, Pablo R; Phillips, Oliver; Cogollo, Álvaro; Peñuela, Maria C; von Hildebrand, Patricio; Jiménez, Eliana; Melo, Omar; Londoño-Vega, Ana Catalina; Mendoza, Irina; Velásquez, Oswaldo; Fernández, Fernando; Serna, Marcela; Velázquez-Rua, Cesar; Benítez, Doris; Rey-Benayas, José M
2017-01-01
Understanding and predicting the likely response of ecosystems to climate change are crucial challenges for ecology and for conservation biology. Nowhere is this challenge greater than in the tropics as these forests store more than half the total atmospheric carbon stock in their biomass. Biomass is determined by the balance between biomass inputs (i.e., growth) and outputs (mortality). We can expect therefore that conditions that favor high growth rates, such as abundant water supply, warmth, and nutrient-rich soils will tend to correlate with high biomass stocks. Our main objective is to describe the patterns of above ground biomass (AGB) stocks across major tropical forests across climatic gradients in Northwestern South America. We gathered data from 200 plots across the region, at elevations ranging between 0 to 3400 m. We estimated AGB based on allometric equations and values for stem density, basal area, and wood density weighted by basal area at the plot-level. We used two groups of climatic variables, namely mean annual temperature and actual evapotranspiration as surrogates of environmental energy, and annual precipitation, precipitation seasonality, and water availability as surrogates of water availability. We found that AGB is more closely related to water availability variables than to energy variables. In northwest South America, water availability influences carbon stocks principally by determining stand structure, i.e. basal area. When water deficits increase in tropical forests we can expect negative impact on biomass and hence carbon storage.
Determination of the Electronics Charge--Electrolysis of Water Method.
ERIC Educational Resources Information Center
Venkatachar, Arun C.
1985-01-01
Presents an alternative method for measuring the electronic charge using data from the electrolysis of acidified distilled water. The process (carried out in a commercially available electrolytic cell) has the advantage of short completion time so that students can determine electron charge and mass in one laboratory period. (DH)
Determining Regional Sensitivity to Energy-Related Water Withdrawals in Minnesota
NASA Astrophysics Data System (ADS)
McCulloch, A.; Brauman, K. A.
2015-12-01
Minnesota has abundant freshwater resources, yet concerns about water-impacts of energy and mining development are increasing. Statewide, total annual water withdrawals have increased, and, in some watersheds, withdrawals make up a large fraction of available water. The energy and mining sectors play a critical role in determining water availability, as water is used to irrigate biofuel feedstock crops, cool thermoelectric plants, and process and transport fuels and iron ore. We evaluated the Minnesota Department of Natural Resources (DNR) Water and Reporting System (MPARS) dataset (1988-2014) to identify regions where energy and mining-related water withdrawals are high or where they are increasing. The energy and mining sectors account for over 65 percent of total water extractions in Minnesota, but this percentage is greater in some regions. In certain southern and northeastern Minnesota watersheds, these extractions account for 90 percent of total water demand. Sensitivity to these demands is not dependent on total water demand alone, and is also not uniform among watersheds. We identified and evaluated factors influencing sensitivity, including population, extraction type (surface water or groundwater), percentage of increased demand, and whether withdrawals are consumptive or not. We determined that southern Minnesota is particularly sensitive to increased water demands, because of growing biofuel and sand extraction industries (the products of which are used in hydraulic fracturing). In the last ten years, ethanol production in Minnesota has increased by 440 percent, and over fifteen refineries (each with a capacity over 1.1 billion gallons), have been built. These users primarily extract from surface water bodies within a few watersheds, compromising local supplies. As these energy-related industries continue to grow, so will the demand for freshwater resources. Determining regional sensitivity to increased demands will allow policy-makers to manage the increased competition for Minnesota's future water supplies.
Liscum, Fred; Brown, D.W.; Kasmarek, M.C.
1997-01-01
The study area, a metropolitan area in southeast Texas about 45 miles north of the Gulf of Mexico, has been undergoing extensive urban development since the 1950s. The Houston Urban Runoff Program was begun by the U.S. Geological Survey in water year 1964 to define the magnitude and frequency of flood peaks, to determine the impact of continuing urban development on surface-water hydrologic responses, and to determine variations in stream water quality for different flow conditions, seasons, and urban development. An extensive data base has been developed.During water years 1964-89, the Houston Urban Runoff Program collected information from a total of 54 U.S. Geological Survey streamflow-gaging stations, 30 U.S. Geological Survey water-quality sampling sites, and 102 rain gages (operated by the U.S. Geological Survey, the National Weather Service, and local agencies). In addition, basin characteristics were developed to aid in understanding the effects of urban development on surface-water hydrologic responses.Surface-water hydrologic data on diskettes describe the 54 U.S. Geological Survey streamflow-gaging stations, list annual peaks (and where available, peaks above an arbitrary base) for 50 streamflow sites, tabulate 1,125 storm hydrographs from 43 sites, and document 102 waterquality parameters determined from 3,242 available samples.
Comparison of methods to determine the microbial quality of alternative irrigation waters
USDA-ARS?s Scientific Manuscript database
The availability of water for crop irrigation is decreasing due to droughts, population growth, and pollution. Implementation of Food Safety and Modernization Act (FSMA) for irrigation water standards discourages growers to use poor microbial quality water for produce crop irrigation. We evaluated m...
Betanzo, Elin A.; Hagen, Erik R.; Wilson, John T.; Reckhow, Kenneth H.; Hayes, Laura; Argue, Denise M.; Cangelosi, Allegra A.
2016-01-01
Throughout its history, the United States has made major investments in assessing natural resources, such as soils, timber, oil and gas, and water. These investments allow policy makers, the private sector and the American public to make informed decisions about cultivating, harvesting or conserving these resources to maximize their value for public welfare, environmental conservation and the economy. As policy issues evolve, new priorities and challenges arise for natural resource assessment, and new approaches to monitoring are needed. For example, new technologies for oil and gas development or alternative energy sources may present new risks for water resources both above and below ground. There is a need to evaluate whether today’s water monitoring programs are generating the information needed to answer questions surrounding these new policy priorities. The Northeast-Midwest Institute (NEMWI), in cooperation with the U.S. Geological Survey (USGS) National Water-Quality Assessment (NAWQA) Program, initiated this project to explore the types and amounts of water data needed to address water-quality related policy questions of critical concern to today’s policy makers and whether those data are currently available. The collaborating entities identified two urgent water policy questions and conducted case studies in the Northeast-Midwest region to determine the water data needed, water data available, and the best ways to fill the data gaps relative to those questions. This report details the output from one case study and focuses on the Susquehanna River Basin, a data-rich area expected to be a best-case scenario in terms of water data availability.
Parkhurst, David L.; Christenson, Scott C.; Schlottmann, Jamie L.
1989-01-01
Beginning in 1986, the Congress annually has appropriated funds for the U.S. Geological Survey to test and refine concepts for a National Water-Quality Assessment (NAWQA) Program. The long-term goals of a full-scale program would be to:Provide a nationally consistent description of current water-quality conditions for a large part of the Nation's surface- and ground-water resources;Define long-term trends (or lack of trends) in water quality; andIdentify, describe, and explain, as possible, the major factors that affect the observed water-quality conditions and trends.The results of the NAWQA Program will be made available to water managers, policy makers, and the public, and will provide an improved scientific basis for evaluating the effectiveness of water-quality management programs.At present (1988), the assessment program is in a pilot phase in seven project areas throughout the country that represent diverse hydrologic environments and water-quality conditions. The Central Oklahoma aquifer project is one of three pilot ground-water projects. One of the initial activities performed by each pilot project was to compile, screen, and interpret the large amount of water-quality data available within each study unit.The purpose of this report is to assess the water quality of the Central Oklahoma aquifer using the information available through 1987. The scope of the work includes compiling data from Federal, State, and local agencies; evaluating the suitability of the information for conducting a regional water-quality assessment; mapping regional variations in major-ion chemistry; calculating summary statistics of the available water-quality data; producing maps to show the location and number of samples that exceeded water-quality standards; and performing contingency-table analyses to determine the relation of geologic unit and depth to the occurrence of chemical constituents that exceed water-quality standards. This report provides an initial description of water-quality conditions in the Central Oklahoma aquifer study unit. No attempt was made in this report to determine the causes for regional variations in major-ion chemistry or to examine the reasons that some chemical constituents exceed water-quality standards.
40 CFR 141.803 - Coliform sampling.
Code of Federal Regulations, 2012 CFR
2012-07-01
... aircraft water system, the sampling frequency must be determined by the disinfection and flushing frequency... disinfection and flushing frequency recommended by the aircraft water system manufacturer, when available. Where the aircraft water system manufacturer does not specify a recommended routine disinfection and...
NASA Technical Reports Server (NTRS)
Jeffries, Martin; Morris, Kim; Liston, Glen
1996-01-01
Images taken by the ERS-1 synthetic aperture radar (SAR) were used to identify and to differentiate between the lakes that freeze completely to the bottom and those that do not, on the North Slope, in northwestern Alaska. The ice thickness at the time each lake froze completely is determined with numerical ice growth model that gives a maximum simulated thickness of 2.2 m. A method combining the ERS-1 SAR images and numerical ice growth model was used to determine the ice growth and the water availability in these regions.
Comparison of the Mineral Content of Tap Water and Bottled Waters
Azoulay, Arik; Garzon, Philippe; Eisenberg, Mark J
2001-01-01
OBJECTIVES Because of growing concern that constituents of drinking water may have adverse health effects, consumption of tap water in North America has decreased and consumption of bottled water has increased. Our objectives were to 1) determine whether North American tap water contains clinically important levels of calcium (Ca2+), magnesium (Mg2+), and sodium (Na+) and 2) determine whether differences in mineral content of tap water and commercially available bottled waters are clinically important. DESIGN We obtained mineral analysis reports from municipal water authorities of 21 major North American cities. Mineral content of tap water was compared with published data regarding commercially available bottled waters and with dietary reference intakes (DRIs). MEASUREMENTS AND MAIN RESULTS Mineral levels varied among tap water sources in North America and among bottled waters. European bottled waters generally contained higher mineral levels than North American tap water sources and North American bottled waters. For half of the tap water sources we examined, adults may fulfill between 8% and 16% of their Ca2+ DRI and between 6% and 31% of their Mg2+ DRI by drinking 2 liters per day. One liter of most moderate mineralization European bottled waters contained between 20% and 58% of the Ca2+ DRI and between 16% and 41% of the Mg2+ DRI in adults. High mineralization bottled waters often contained up to half of the maximum recommended daily intake of Na+. CONCLUSION Drinking water sources available to North Americans may contain high levels of Ca2+, Mg2+, and Na+ and may provide clinically important portions of the recommended dietary intake of these minerals. Physicians should encourage patients to check the mineral content of their drinking water, whether tap or bottled, and choose water most appropriate for their needs. PMID:11318912
A generic hydroeconomic model to assess future water scarcity
NASA Astrophysics Data System (ADS)
Neverre, Noémie; Dumas, Patrice
2015-04-01
We developed a generic hydroeconomic model able to confront future water supply and demand on a large scale, taking into account man-made reservoirs. The assessment is done at the scale of river basins, using only globally available data; the methodology can thus be generalized. On the supply side, we evaluate the impacts of climate change on water resources. The available quantity of water at each site is computed using the following information: runoff is taken from the outputs of CNRM climate model (Dubois et al., 2010), reservoirs are located using Aquastat, and the sub-basin flow-accumulation area of each reservoir is determined based on a Digital Elevation Model (HYDRO1k). On the demand side, agricultural and domestic demands are projected in terms of both quantity and economic value. For the agricultural sector, globally available data on irrigated areas and crops are combined in order to determine irrigated crops localization. Then, crops irrigation requirements are computed for the different stages of the growing season using Allen (1998) method with Hargreaves potential evapotranspiration. Irrigation water economic value is based on a yield comparison approach between rainfed and irrigated crops. Potential irrigated and rainfed yields are taken from LPJmL (Blondeau et al., 2007), or from FAOSTAT by making simple assumptions on yield ratios. For the domestic sector, we project the combined effects of demographic growth, economic development and water cost evolution on future demands. The method consists in building three-blocks inverse demand functions where volume limits of the blocks evolve with the level of GDP per capita. The value of water along the demand curve is determined from price-elasticity, price and demand data from the literature, using the point-expansion method, and from water costs data. Then projected demands are confronted to future water availability. Operating rules of the reservoirs and water allocation between demands are based on the maximization of water benefits, over time and space. A parameterisation-simulation-optimisation approach is used. This gives a projection of future water scarcity in the different locations and an estimation of the associated direct economic losses from unsatisfied demands. This generic hydroeconomic model can be easily applied to large-scale regions, in particular developing regions where little reliable data is available. We will present an application to Algeria, up to the 2050 horizon.
Determination of Color in Water. Training Module 5.250.2.77.
ERIC Educational Resources Information Center
Bonte, John L.; Davidson, Arnold C.
This document is an instructional module package prepared in objective form for use by an instructor familiar with the determination of color in water using the visual comparison method and the spectrophotometric method. Included are objectives, instructor guide, student handouts, and transparency masters. A videotape is also available from the…
Socioeconomic differentials and availability of domestic water in South Africa
NASA Astrophysics Data System (ADS)
Dungumaro, Esther W.
The past few decades has seen massive efforts to increasing provision of domestic water. However, water is still unavailable to many people most of them located in sub-Saharan Africa, South Asia and East Asia. Furthermore, availability of water varies greatly both spatially and temporary. While other people pay so dearly for domestic water others have an easy access to adequate clean water and sanitation. Accessibility and affordability of domestic water and sanitation is determined by a great variety of factors including socioeconomic status of households. The main objective of the paper is to inform on factors which need to be taken into account when coming up with projects to provide domestic water. It is more critical when the issue of water pricing comes into the equation. Water pricing has many facets, including equity, willingness to pay and affordability. In this premise, it is deemed important to understand the socioeconomic characteristics of the people before deciding on the amount of money they will have to pay for water consumption. It is argued that understanding people’s socioeconomic situation will greatly help to ensure that principles of sustainability and equity in water allocation and pricing are achieved. To do so, the paper utilized 2002 South Africa General Household Survey (GHS), to analyze socioeconomic variables and availability of domestic water. Analysis was mainly descriptive. However, logistic regression analysis was also utilized to determine the likelihood of living in a household that obtain water from a safe source. The study found that there is a strong relationship between availability of domestic water and socioeconomic conditions. Economic status, household size and to a lesser extent gender of head of household were found to be strong predictors of living in a household which obtained water from a safe source. The paper recommends that needs and priorities for interventions in water provision should take into account socioeconomic status of households.
USGS Regional Groundwater Availability Studies: Quantifying Aquifer Response
NASA Astrophysics Data System (ADS)
Reeves, H. W.
2017-12-01
The U.S. Geological Survey (USGS) identified six challenges in determining groundwater availability: 1) limited direct measurement, 2) varying response times for different systems, 3) varying spatial scales for different availability questions and aquifer systems, 4) varying tolerance to changes in water levels or outflows, 5) redistribution of stresses and potential return-flow of water pumped from the system, and 6) varying chemical quality of groundwater and the role of quality in determining suitability for different uses. USGS Regional groundwater availability studies are designed to address these challenges. USGS regional groundwater availability studies focus on quantifying the groundwater budget for principal aquifers and determining how this budget has changed in response to pumping or variations in climate. This focus requires relating limited measurements to a quantitative understanding of the temporal and spatial response of regional aquifers. For most principal aquifer studies, aquifer response is quantified using regional groundwater flow models, and USGS regional groundwater availability studies have provided test cases for the development and application of advanced modeling techniques and methods. Results from regional studies from the Lake Michigan Basin and Northern Atlantic Coastal Plain illustrate how different parts of these systems respond differently to pumping with some areas showing large drawdowns and others having much less drawdown but greater capture of discharge. The Central Valley and Mississippi Embayment studies show how extensive pumping and transfer of water have resulted in much more groundwater moving through the aquifer system under current conditions compared to pre-development. These and other results from regional studies will be explored to illustrate how regional groundwater availability and related studies address the six challenges to determining groundwater availability.
The influence of nutrient and water availability on carbohydrate storage in loblolly pine
K.H. Ludovici; H.L. Allen; T.J. Albaugh; P.M. Dougherty
2002-01-01
We quantified the effects of nutrient and water availability on monthly whole-tree carbohydrate budgets and determined allocation patterns of storage carbohydrates in loblolly pine (Pinus taeda) to test site resource impacts on internal carbon (C) storage. A factorial combination of two nutrient and two irrigation treatments were imposed on a 7-year...
Assessing groundwater availability in the Northern Atlantic Coastal Plain aquifer system
Masterson, John P.; Pope, Jason P.; Monti, Jack; Nardi, Mark R.
2011-01-01
The U.S. Geological Survey's Groundwater Resources Program is conducting an assessment of groundwater availability throughout the United States to gain a better understanding of the status of the Nation's groundwater resources and how changes in land use, water use, and climate may affect those resources. The goal of this National assessment is to improve our ability to forecast water availability for future economic and environmental uses. Assessments will be completed for the Nation's principal aquifer systems to help characterize how much water is currently available, how water availability is changing, and how much water we can expect to have in the future (Reilly and others, 2008). The concept of groundwater availability is more than just how much water can be pumped from any given aquifer. Groundwater availability is a function of many factors, including the quantity and quality of water and the laws, regulations, economics, and environmental factors that control its use. The primary objective of the North Atlantic Coastal Plain groundwater-availability study is to identify spatial and temporal changes in the overall water budget by more fully determining the natural and human processes that control how water enters, moves through, and leaves the groundwater system. Development of tools such as numerical models can help hydrologists gain an understanding of this groundwater system, allowing forecasts to be made about the response of this system to natural and human stresses, and water quality and ecosystem health to be analyzed, throughout the region.
Investigating the water consumption for electricity generation at Turkish power plants
NASA Astrophysics Data System (ADS)
El-Khozondar, Balkess; Aydinalp Koksal, Merih
2017-11-01
The water-energy intertwined relationship has recently gained more importance due to the high water consumption in the energy sector and to the limited availability of the water resources. The energy and electricity demand of Turkey is increasing rapidly in the last two decades. More thermal power plants are expected to be built in the near future to supply the rapidly increasing demand in Turkey which will put pressure on water availability. In this study, the water consumption for electricity generation at Turkish power plants is investigated. The main objectives of this study are to identify the amount of water consumed to generate 1 kWh of electricity for each generation technology currently used in Turkey and to investigate ways to reduce the water consumption at power plants expected to be built in the near future to supply the increasing demand. The various electricity generation technology mixture scenarios are analyzed to determine the future total and per generation water consumption, and water savings based on changes of cooling systems used for each technology. The Long-range Energy Alternatives Planning (LEAP) program is used to determine the minimum water consuming electricity generation technology mixtures using optimization approaches between 2017 and 2035.
Technical Note: Seasonality in alpine water resources management - a regional assessment
NASA Astrophysics Data System (ADS)
Vanham, D.; Fleischhacker, E.; Rauch, W.
2008-01-01
Alpine regions are particularly affected by seasonal variations in water demand and water availability. Especially the winter period is critical from an operational point of view, as being characterised by high water demands due to tourism and low water availability due to the temporal storage of precipitation as snow and ice. The clear definition of summer and winter periods is thus an essential prerequisite for water resource management in alpine regions. This paper presents a GIS-based multi criteria method to determine the winter season. A snow cover duration dataset serves as basis for this analysis. Different water demand stakeholders, the alpine hydrology and the present day water supply infrastructure are taken into account. Technical snow-making and (winter) tourism were identified as the two major seasonal water demand stakeholders in the study area, which is the Kitzbueheler region in the Austrian Alps. Based upon different geographical datasets winter was defined as the period from December to March, and summer as the period from April to November. By determining potential regional water balance deficits or surpluses in the present day situation and in future, important management decisions such as water storage and allocation can be made and transposed to the local level.
Kraemer, T.F.; Doughten, M.W.; Bullen, T.D.
2002-01-01
A method is described that allows precise determination of 234U/238U activity ratios (UAR) in most natural waters using commonly available inductively coupled plasma/mass spectrometry (ICP/MS) instrumentation and accessories. The precision achieved by this technique (??0.5% RSD, 1 sigma) is intermediate between thermal ionization mass spectrometry (??0.25% RSID, 1 sigma) and alpha particle spectrometry (??5% RSD, 1 sigma). It is precise and rapid enough to allow analysis of a large number of samples in a short period of time at low cost using standard, commercially available quadrupole instrumentation with ultrasonic nebulizer and desolvator accessories. UARs have been analyzed successfully in fresh to moderately saline waters with U concentrations of from less than 1 ??g/L to nearly 100 ??g/L. An example of the uses of these data is shown for a study of surface-water mixing in the North Platte River in western Nebraska. This rapid and easy technique should encourage the wider use of uranium isotopes in surface-water and groundwater investigations, both for qualitative (e.g. identifying sources of water) and quantitative (e.g. determining end-member mixing ratios purposes.
NASA Technical Reports Server (NTRS)
Cihlar, J. (Principal Investigator)
1980-01-01
Progress in the compilation and analysis of airborne and ground data to determine the relationship between the maximum surface minus maximum air temperature differential (delta Tsa) and available water (PAW) is reported. Also, results of an analysis of HCMM images to determine the effect of cloud cover on the availability of HCMM-type data are presented. An inverse relationship between delta Tsa and PAW is indicated along with stable delta Tsa vs. PAW distributions for fully developed canopies. Large variations, both geographical and diurnal, in the cloud cover images are reported. The average monthly daytime cloud cover fluctuated between 40 and 60 percent.
Water assessment for the Lower Colorado River region-emerging energy technology development
NASA Astrophysics Data System (ADS)
1981-08-01
Water supply availability for two hypothetical levels of emerging energy technology development are assessed. The water and related land resources implications of such hypothetical developments are evaluated. Water requirement, the effects on water quality, costs of water supplies, costs of disposal of wastewaters, and the environmental, economic and social impacts are determined, providing information for the development of non-nuclear energy research.
Perceptions about availability and adequacy of drinking water in a large California school district.
Patel, Anisha I; Bogart, Laura M; Uyeda, Kimberly E; Rabin, Alexa; Schuster, Mark A
2010-03-01
Concerns about the influence of sugar-sweetened beverage consumption on obesity have led experts to recommend that water be freely available in schools. We explored perceptions about the adequacy of drinking water provision in a large California school district to develop policies and programs to encourage student water consumption. From March to September 2007, we used semistructured interviews to ask 26 California key stakeholders - including school administrators and staff, health and nutrition agency representatives, and families - about school drinking water accessibility; attitudes about, facilitators of, and barriers to drinking water provision; and ideas for increasing water consumption. Interviews were analyzed to determine common themes. Although stakeholders said that water was available from school drinking fountains, they expressed concerns about the appeal, taste, appearance, and safety of fountain water and worried about the affordability and environmental effect of bottled water sold in schools. Stakeholders supported efforts to improve free drinking water availability in schools, but perceived barriers (eg, cost) and mistaken beliefs that regulations and beverage contracts prohibit serving free water may prevent schools from doing so. Some schools provide water through cold-filtered water dispensers and self-serve water coolers. This is the first study to explore stakeholder perceptions about the adequacy of drinking water in US schools. Although limited in scope, our study suggests that water available in at least some schools may be inadequate. Collaborative efforts among schools, communities, and policy makers are needed to improve school drinking water provision.
Philip E. Dennison; Dar A. Roberts; Sommer R. Thorgusen; Jon C. Regelbrugge; David Weise; Christopher Lee
2003-01-01
Live fuel moisture, an important determinant of fire danger in Mediterranean ecosystems, exhibits seasonal changes in response to soil water availability. Both drought stress indices based on meteorological data and remote sensing indices based on vegetation water absorption can be used to monitor live fuel moisture. In this study, a cumulative water balance index (...
Chemistry of spring and well waters on Kilauea Volcano, Hawaii, and vicinity
DOE Office of Scientific and Technical Information (OSTI.GOV)
Janik, C.J.; Nathenson, M.; Scholl, M.A.
1994-12-31
Published and new data for chemical and isotopic samples from wells and springs on Kilauea Volcano and vicinity are presented. These data are used to understand processes that determine the chemistry of dilute meteoric water, mixtures with sea water, and thermal water. Data for well and spring samples of non-thermal water indicate that mixing with sea water and dissolution of rock from weathering are the major processes that determine the composition of dissolved constituents in water. Data from coastal springs demonstrate that there is a large thermal system south of the lower east rift of Kilauea. Samples of thermal watermore » from shallow wells in the lower east rift and vicinity have rather variable chemistry indicating that a number of processes operate in the near surface. Water sampled from the available deep wells is different in composition from the shallow thermal water, indicating that generally there is not a significant component of deep water in the shallow wells. Data for samples from available deep wells show significant gradients in chemistry and steam content of the reservoir fluid. These gradients are interpreted to indicate that the reservoir tapped by the existing wells is an evolving vapor-dominated system.« less
NASA Astrophysics Data System (ADS)
Suyarto, R.; Sunarta, I. N.; Wiyanti; Padmayani, N. K. H.
2017-12-01
Pelaga Village is located in Badung regency which has the advantage in agriculture with the cultivation of coffee plants, oranges, carrots, cabbage, and chili. The physical condition of Pelaga Village which has high rainfall, bumpy areas, and sandy-sandy ground texture causes air to air to be available for plants. Based on these questions then conducted a study to determine the comparison between the available water and water requirement for agriculture. Available water was difference field capacity and permanent wilting point method and crop water requirement was using Blaney-Criddle method. The results from this research was deficit between available air and crop water requirements. Available water was 12,12% and crop water requirement in initial stage, dev. Stage, mid-season stage, and late season stage respectively, coffee 11.28%, 24.19%, 35.49%, 29.04%; cabbage 19.58%, 19.58%, 33.10%, 27.74%: carrot 14.82%, 28.61%, 28.61%, 27.95%: Orange 14.82%, 28.61%, 28.61%, 27.23%; chili, 17.37%,17.37%, 34.80%, 30.46%. Soil management that must be done is by short-term land management by sprinkling long-term soil management by means of organic material valuation, irrigation making, and terracing making.
Jeremy J. James; Tony Svejcar
2010-01-01
Seeding rangeland following wildfire is a central tool managers use to stabilize soils and inhibit the spread of invasive plants. Rates of successful seeding on arid rangeland, however, are low. The objective of this study was to determine the degree to which water availability, invasive plant abundance, and seeding technology influence postfire seedling establishment...
Alison Whittaker; Bruce Roundy; Jeanne Chambers; Susan Meyer; Robert Blank; Stanley Kitchen; John Korfmacher
2008-01-01
Over the past several decades, cheatgrass (Bromus tectorum) has been continually expanding in the sagebrush steppe ecosystem. There has been very little research that examines why cheatgrass is able to invade these communities. To determine the effects of herbaceous vegetation removal and fire on available water for cheatgrass invasion, as well as...
Reduction of Turbidity of Water Using Locally Available Natural Coagulants
Asrafuzzaman, Md.; Fakhruddin, A. N. M.; Hossain, Md. Alamgir
2011-01-01
Turbidity imparts a great problem in water treatment. Moringa oleifera, Cicer arietinum, and Dolichos lablab were used as locally available natural coagulants in this study to reduce turbidity of synthetic water. The tests were carried out, using artificial turbid water with conventional jar test apparatus. Optimum mixing intensity and duration were determined. After dosing water-soluble extracts of Moringa oleifera, Cicer arietinum, and Dolichos lablab reduced turbidity to 5.9, 3.9, and 11.1 nephelometric turbidity unit (NTU), respectively, from 100 NTU and 5, 3.3, and 9.5, NTU, respectively, after dosing and filtration. Natural coagulants worked better with high, turbid, water compare to medium, or low, turbid, water. Highest turbidity reduction efficiency (95.89%) was found with Cicer arietinum. About 89 to 96% total coliform reduction were also found with natural coagulant treatment of turbid water. Using locally available natural coagulants, suitable, easier, and environment friendly options for water treatment were observed. PMID:23724307
Lower limits of crop water use in three soil textural classes
USDA-ARS?s Scientific Manuscript database
Accurate knowledge of the amount of soil water available for crop use allows better management of limited water supplies. Using neutron scattering, we determined the mean lower limit of field soil water use (LL*F, m**3 m**-3) to a depth of 2.2 m at harvest (three seasons each) of short-season maize...
Root response of Jerusalem artichoke genotypes to different water regimes
USDA-ARS?s Scientific Manuscript database
The objective of this study was to determine effects of drought on selected root growth parameters and develop relationships between root parameters and tuber yield for selected Jerusalem artichoke (JA) genotypes. Three water regimes (Field capacity, 50% available water (AW) and 25% AW) and five JA...
Shallow ground-water conditions, Tom Green County, Texas
Lee, J.N.
1986-01-01
Pollution from oil-field activities may affect the quality of water in some isolated wells and in some areas in the county. No historical records are available for determining any changes in pesticides, minor elements, or bacteria.
Berger, David L.; Halford, Keith J.; Belcher, Wayne R.; Lico, Michael S.
2008-01-01
The Nevada State Engineer in Ruling No. 5181 required Lincoln County and Vidler Water Company, Inc., to provide results from additional water-resources studies of Tule Desert in southern Nevada to support water-rights application 64692. As outlined by the ruling, the additional studies were to include the determination of the amount of ground water available from the Tule Desert basin, ground-water recharge to the Tule Desert, and the direction of ground-water flow. Results of these additional studies were published in five reports prepared for Lincoln County and Vidler Water Company, Inc. The National Park Service formally requested that the U.S. Geological Survey provide technical reviews of these five reports. The Nevada State Engineer in Ruling No. 5181 required Lincoln County and Vidler Water Company, Inc., to provide results from additional water-resources studies of Tule Desert in southern Nevada to support water-rights application 64692. As outlined by the ruling, the additional studies were to include the determination of the amount of ground water available from the Tule Desert basin, ground-water recharge to the Tule Desert, and the direction of ground-water flow. Results of these additional studies were published in five reports prepared for Lincoln County and Vidler Water Company, Inc. The National Park Service formally requested that the U.S. Geological Survey provide technical reviews of these five reports.
Gątarska, Anna; Tońska, Elżbieta; Ciborska, Joanna
2016-01-01
Natural mineral waters may be an essential source of calcium, magnesium and other minerals. In bottled waters, minerals occur in an ionized form which is very well digestible. However, the concentration of minerals in underground waters (which constitute the material for the production of bottled waters) varies. In view of the above, the type of water consumed is essential. The aim of the study was to estimate the calcium and magnesium contents in products available on the market and to evaluate calcium and magnesium consumption with natural mineral water by different consumer groups with an assumed volume of the consumed product. These represented forty different brands of natural mineral available waters on Polish market. These waters were produced in Poland or other European countries. Among the studied products, about 30% of the waters were imported from Lithuania, Latvia, Czech Republic, France, Italy and Germany. The content of calcium and magnesium in mineral waters was determined using flame atomic absorption spectrometry in an acetylene-air flame. Further determinations were carried out using atomic absorption spectrometer--ICE 3000 SERIES-THERMO-England, equipped with a GLITE data station, background correction (a deuterium lamp) as well as other cathode lamps. Over half of the analysed natural mineral waters were medium-mineralized. The natural mineral waters available on the market can be characterized by a varied content of calcium and magnesium and a high degree of product mineralization does not guarantee significant amounts of these components. Among the natural mineral waters available on the market, only a few feature the optimum calcium-magnesium proportion (2:1). Considering the mineralization degree of the studied products, it can be stated that the largest percentage of products with significant calcium and magnesium contents can be found in the high-mineralized water group. For some natural mineral waters, the consumption of 1 litre daily may ensure the recommended intake levels of calcium and magnesium in some consumer groups to a considerable degree. For 1-3-year-old children it is recommended to consume less than 1 litre daily of natural mineral waters containing an excess of 700 mg of calcium and 80 mg of magnesium in 1 litre.
18 CFR 806.12 - Constant-rate aquifer testing.
Code of Federal Regulations, 2014 CFR
2014-04-01
... withdraw or increase a withdrawal of groundwater shall perform a constant-rate aquifer test in accordance... groundwater availability analysis to determine the availability of water during a 1-in-10-year recurrence...
18 CFR 806.12 - Constant-rate aquifer testing.
Code of Federal Regulations, 2012 CFR
2012-04-01
... withdraw or increase a withdrawal of groundwater shall perform a constant-rate aquifer test in accordance... groundwater availability analysis to determine the availability of water during a 1-in-10-year recurrence...
18 CFR 806.12 - Constant-rate aquifer testing.
Code of Federal Regulations, 2011 CFR
2011-04-01
... withdraw or increase a withdrawal of groundwater shall perform a constant-rate aquifer test in accordance... groundwater availability analysis to determine the availability of water during a 1-in-10-year recurrence...
18 CFR 806.12 - Constant-rate aquifer testing.
Code of Federal Regulations, 2013 CFR
2013-04-01
... withdraw or increase a withdrawal of groundwater shall perform a constant-rate aquifer test in accordance... groundwater availability analysis to determine the availability of water during a 1-in-10-year recurrence...
Topographic, edaphic, and vegetative controls on plant-available water
Dymond, Salli F.; Bradford, John B.; Bolstad, Paul V.; Kolka, Randall K.; Sebestyen, Stephen D.; DeSutter, Thomas S.
2017-01-01
Soil moisture varies within landscapes in response to vegetative, physiographic, and climatic drivers, which makes quantifying soil moisture over time and space difficult. Nevertheless, understanding soil moisture dynamics for different ecosystems is critical, as the amount of water in a soil determines a myriad ecosystem services and processes such as net primary productivity, runoff, microbial decomposition, and soil fertility. We investigated the patterns and variability in in situ soil moisture measurements converted to plant-available water across time and space under different vegetative cover types and topographic positions at the Marcell Experimental Forest (Minnesota, USA). From 0 – 228.6 cm soil depth, plant-available water was significantly higher under the hardwoods (12%), followed by the aspen (8%) and red pine (5%) cover types. Across the same soil depth, toeslopes were wetter (mean plant-available water = 10%) than ridges and backslopes (mean plant-available water was 8%), although these differences were not statistically significant (p < 0.05). Using a mixed model of fixed and random effects, we found that cover type, soil texture, and time were related to plant-available water and that topography was not significantly related to plant-available water within this low-relief landscape. Additionally, during the three-year monitoring period, red pine and quaking aspen sites experienced plant-available water levels that may be considered limiting to plant growth and function. Given that increasing temperatures and more erratic precipitation patterns associated with climate change may result in decreased soil moisture in this region, these species may be sensitive and vulnerable to future shifts in climate.
Code of Federal Regulations, 2010 CFR
2010-01-01
... conservation includes actions that, for a given level of water supply, reduce the demand for or use of water by... reuse of water, thereby making existing supplies available for other current or future uses; or (iv) Improving land management practices for the purpose of reducing water use, loss, waste, increasing the...
Improved methods for national water assessment, water resources contract: WR15249270
Thomas, Harold A.
1981-01-01
The purpose of our research is to develop methods to make National Water Assessment more useful in estimating water availability for economic growth and more helpful in determining the effect of water resource development upon the environmental quality of related land resources. There are serious questions pertaining to the 1975 Water Assessment and these amplify the significance of decisions made as to the planning and scheduling of the next assessment.
Optimal foraging of a herbivorous lizard, the green iguana in a seasonal environment.
van Marken Lichtenbelt, Wouter D
1993-08-01
Food selection was studied in free living green iguanas (Iguana iguana) throughout the year in a semiarid environment, Curaçao (Netherlands Antilles). Food intake was determined by direct observations and converted into biomass intake. Comparison between intake and biomass availability of the various food items revealed that the lizards were selective, and that changes in seasonal food availability led to periodic switching of food plants. The extent to which nutrient constraints determine iguana feeding ecology was investigated. Potential constraints were the requirements for water, digestible crude protein, and metabolizable energy. By using a linear programming model that incorporates characteristics of the food (chemical composition, energy content, item size) and requirements and constraints of the green iguanas (nutrient and energy requirements digestive tract capacity, feeding rate) it was possible to identify which factors determine food choice over the year. During the dry period, when the iguanas had no access to drinking water they consumed flowers to increase water intake, though the amount of flowers consumed was too low to cover maintenance requirements for either energy or protein. After the young leaf flush, following the early rains in May, the biomass increased, free surface water was available during showers, and the linear programming solutions indicate that food selection conformed to the protein maximization criterion. Reproduction in green iguanas shows an annual cycle, in which oviposition takes place at the end of the dry season, when intake is below maintenance levels. Females show a 8-10 month gap between acquisition of most of the protein required for egg synthesis and the act of laying. Thus, as in avian and mammalian herbivores, food availability during a period prior to the energy and protein demanding reproductive season of iguanas determines reproductive success.
The chlorinated salts of cyanuric acid have found an important role in recreational swimming pool waters across the United States. Upon application to pool water, they can (1) release disinfectant chlorine or (2) stabilize the free available chlorine by acting as chlorine reserv...
The available data resources in the State of Iowa were used to investigate the relationships of drinking water contaminants and cancer incidence rates for communities. Age-adjusted, sex-specific cancer incidence rates for the years 1969-1978 were determined for municipalities hav...
Fish habitat in lakes is strongly constrained by water temperature and available dissolved oxygen (DO). Suitable fish habitat for three fish assemblages (cold-, cool-, and warm-water) in Minnesota (US) lakes was therefore determined from simulated daily water ...
Diffuse attenuation of solar light (Kd, m−1) determines the percentage of light penetrating the water column and available for benthic organisms. Therefore, Kd can be used as an index of water quality for coastal ecosystems that are dependent on photosynthesis, such as the coral ...
Assessing water use and quality through youth participatory research in a rural Andean watershed.
Roa García, C E; Brown, S
2009-07-01
Water availability, use and quality in a rural watershed of the Colombian Andes were investigated through participatory research involving local youth. Research included the quantification of disaggregated water use at the household level; comparison of water use with availability; monitoring water quality of streams, community water intakes and household faucets; and the determination of land use-water quality interactions. Youth were involved in all aspects of the research from design to implementation, dissemination of results and remediation options. Quantification of domestic and on-farm water use, and water availability indicated that water availability was sufficient during the study period, but that only an 8% decrease in dry season supply would result in shortages. Elevated conductivity levels in the headwaters were related to "natural" bank erosion, while downstream high conductivity and coliform levels were associated with discharges from livestock stalls and poorly maintained septic tanks in the stream buffer zone. Through the involvement of youth as co-investigators, the knowledge generated by the research was appropriated at the local level. Community workshops led by local youth promoted water conservation and water quality protection practices based on research, and resulted in broader community participation in water management. The approach involving youth in research stimulated improved management of both land and water resources, and could be applied in small rural watersheds in developed or developing countries.
Bentanzo, Elin A.; Choquette, Anne F.; Reckhow, Kenneth H.; Hayes, Laura; Hagan, Erik R; Argue, Denise M.; Cangelosi, A.A.
2015-01-01
Throughout its history, the United States has made major investments in assessing natural resources, such as soils, timber, oil and gas, and water. These investments allow policy makers, the private sector and the American public to make informed decisions about cultivating, harvesting or conserving these resources to maximize their value for public welfare, environmental conservation and the economy. As policy issues evolve, new priorities and challenges arise for natural resource assessment, and new approaches to monitoring are needed. For example, informed conservation and use of the nation’s finite fresh water resources in the context of increasingly intensive land development is a priority for today’s policy decisionmakers. There is a need to evaluate whether today’s water monitoring programs are generating the information needed to answer questions surrounding these new policy priorities. The Northeast-Midwest Institute (NEMWI), in cooperation with the U.S. Geological Survey (USGS) National Water-Quality Assessment (NAWQA) Program, initiated this project to explore the types and amounts of water data needed to address water-quality related policy questions of critical concern to today’s policy makers. The collaborating entities identified two urgent water policy questions and conducted case studies in the Northeast-Midwest region to determine the water data needed, water data available, and the best ways to fill the data gaps relative to those questions. This report details the output from one case study and focuses on the Lake Erie drainage basin, a data-rich area expected to be a best-case scenario in terms of water data availability.
Water use patterns of estuarine vegetation in a tidal creek system.
Wei, Lili; Lockington, David A; Poh, Seng-Chee; Gasparon, Massimo; Lovelock, Catherine E
2013-06-01
Water availability is a key determinant of the zonation patterns in estuarine vegetation, but water availability and the use of different water sources over space and time are not well understood. We have determined the seasonal water use patterns of riparian vegetation over an estuarine ecotone. Our aim was to investigate how the water use patterns of estuarine vegetation respond to variations in the availability of tidal creek water and rain-derived freshwater. The levels of natural stable isotopes of oxygen and hydrogen were assessed in the stem of the mangrove Avicennia marina (tall and scrub growth forms), Casuarina glauca and Melaleuca quinquenervia that were distributed along transects from river/creek-front towards inland habitats. The isotopic composition of plant tissues and the potential water sources were assessed in both the wet season, when freshwater from rainfall is present, and the dry season, when mangrove trees are expected to be more dependent on tidal water, and when Casuarina and Melaleuca are expected to be dependent on groundwater. Our results indicate that rainwater during the wet season contributes significantly to estuarine vegetation, even to creek-side mangroves which are inundated by tidal creek water daily, and that estuarine vegetation depends primarily on freshwater throughout the year. In contrast, high intertidal scrub mangroves were found to use the greatest proportion of tidal creek water, supplemented by groundwater in the dry season. Contrary to prediction, inland trees C. glauca and M. quinquenervia were found also to rely predominantly on rainwater--even in the dry season. The results of this study reveal a high level of complexity in vegetation water use in estuarine settings.
Water resources of Bannock Creek basin, southeastern Idaho
Spinazola, Joseph M.; Higgs, B.D.
1997-01-01
The potential for development of water resources in the Bannock Creek Basin is limited by water supply. Bannock Creek Basin covers 475 square miles in southeastern Idaho. Shoshone-Bannock tribal lands on the Fort Hall Indian Reservation occupy the northern part of the basin; the remainder of the basin is privately owned. Only a small amount of information on the hydrologic and water-quality characteristics of Bannock Creek Basin is available, and two previous estimates of water yield from the basin ranged widely from 45,000 to 132,500 acre-feet per year. The Shoshone-Bannock Tribes need an accurate determination of water yield and baseline water-quality characteristics to plan and implement a sustainable level of water use in the basin. Geologic setting, quantities of precipitation, evapotranspiration, surface-water runoff, recharge, and ground-water underflow were used to determine water yield in the basin. Water yield is the annual amount of surface and ground water available in excess of evapotranspiration by crops and native vegetation. Water yield from Bannock Creek Basin was affected by completion of irrigation projects in 1964. Average 1965-89 water yield from five subbasins in Bannock Creek Basin determined from water budgets was 60,600 acre-feet per year. Water yield from the Fort Hall Indian Reservation part of Bannock Creek Basin was estimated to be 37,700 acre-feet per year. Water from wells, springs, and streams is a calcium bicarbonate type. Concentrations of dissolved nitrite plus nitrate as nitrogen and fluoride were less than Maximum Contaminant Levels for public drinking-water supplies established by the U.S. Environmental Protection Agency. Large concentrations of chloride and nitrogen in water from several wells, springs, and streams likely are due to waste from septic tanks or stock animals. Estimated suspended-sediment load near the mouth of Bannock Creek was 13,300 tons from December 1988 through July 1989. Suspended-sediment discharge was greatest during periods of high streamflow.
Water resources scientific information center
Cardin, C. William; Campbell, J.T.
1986-01-01
The Water Resources Scientific Information Center (WRSIC) acquires, abstracts and indexes the major water resources related literature of the world, and makes information available to the water resources community and the public. A component of the Water Resources Division of the US Geological Survey, the Center maintains a searchable computerized bibliographic data base, and publishers a monthly journal of abstracts. Through its services, the Center is able to provide reliable scientific and technical information about the most recent water resources developments, as well as long-term trends and changes. WRSIC was established in 1966 by the Secretary of the Interior to further the objectives of the Water Resources Research Act of 1964--legislation that encouraged research in water resources and the prevention of needless duplication of research efforts. It was determined the WRSIC should be the national center for information on water resources, covering research reports, scientific journals, and other water resources literature of the world. WRSIC would evaluate all water resources literature, catalog selected articles, and make the information available in publications or by computer access. In this way WRSIC would increase the availability and awareness of water related scientific and technical information. (Lantz-PTT)
Tsurim, Ido; Sapir, Nir; Belmaker, Jonathan; Shanni, Itai; Izhaki, Ido; Wojciechowski, Michał S; Karasov, William H; Pinshow, Berry
2008-05-01
Fat accumulation by blackcaps (Sylvia atricapilla) is a prerequisite for successful migratory flight in the autumn and has recently been determined to be constrained by availability of drinking water. Birds staging in a fruit-rich Pistacia atlantica plantation that had access to water increased their body mass and fat reserves both faster and to a greater extent than birds deprived of water. We conducted a series of laboratory experiments on birds captured during the autumn migration period in which we tested the hypotheses that drinking water increases food use by easing limitations on the birds' dietary choices and, consequently, feeding and food processing rates, and that the availability of drinking water leads to improved digestion and, therefore, to higher apparent metabolizable energy. Blackcaps were trapped in autumn in the Northern Negev Desert, Israel and transferred to individual cages in the laboratory. Birds were provided with P. atlantica fruit and mealworms, and had either free access to water (controls) or were water-deprived. In experiment 1, in which mealworm availability was restricted, water-deprived birds had a fourfold lower fruit and energy intake rates and, consequently, gained less fat and total mass than control birds. Water availability did not affect food metabolizability. In experiment 2, in which mealworms were provided ad libitum, water availability influenced the birds' diet: water-restricted birds ate more mealworms, while control birds consumed mainly P. atlantica fruit. Further, in experiment 2, fat and mass gain did not differ between the two treatment groups. We conclude that water availability may have important consequences for fat accumulation in migrating birds while they fatten at stopover sites, especially when water-rich food is scarce. Restricted water availability may also impede the blackcap's dietary shift from insectivory to frugivory, a shift probably necessary for successful pre-migratory fattening.
30 CFR 260.114 - How does MMS assign and monitor royalty suspension volumes for eligible leases?
Code of Federal Regulations, 2010 CFR
2010-07-01
... have specified the water depth category for each eligible lease in the final Notice of OCS Lease Sale... OCS Lease Sale Package is available on the MMS Web site. Our determination of water depth for each... royalty suspension volume applicable to each water depth. The following table shows the royalty suspension...
Estimating national water use associated with unconventional oil and gas development
Carter, Janet M.; Macek-Rowland, Kathleen M.; Thamke, Joanna N.; Delzer, Gregory C.
2016-05-18
The U.S. Geological Survey’s (USGS) Water Availability and Use Science Program (WAUSP) goals are to provide a more accurate assessment of the status of the water resources of the United States and assist in the determination of the quantity and quality of water that is available for beneficial uses. These assessments would identify long-term trends or changes in water availability since the 1950s in the United States and help to develop the basis for an improved ability to forecast water avail- ability for future economic, energy-production, and environmental uses. The National Water Census (http://water.usgs.gov/watercensus/), a research program of the WAUSP, supports studies to develop new water accounting tools and assess water availability at the regional and national scales. Studies supported by this program target focus areas with identified water availability concerns and topical science themes related to the use of water within a specific type of environmental setting. The topical study described in this fact sheet will focus on understanding the relation between production of unconventional oil and gas (UOG) for energy and the water needed to produce and sustain this type of energy development. This relation applies to the life-cycle of renewable and nonrenewable forms of UOG energy and includes extraction, production, refinement, delivery, and disposal of waste byproducts. Water-use data and models derived from this topical study will be applied to other similar oil and gas plays within the United States to help resource managers assess and account for water used or needed in these areas. Additionally, the results from this topical study will be used to further refine the methods used in compiling water-use data for selected categories (for example, mining, domestic self-supplied, public supply, and wastewater) in the USGS’s 5-year national water-use estimates reports (http://water.usgs.gov/watuse/).
Carvalho, Ana; Nabais, Cristina; Vieira, Joana; Rossi, Sergio; Campelo, Filipe
2015-01-01
The formation of wood results from cambial activity and its anatomical properties reflect the variability of environmental conditions during the growing season. Recently, it was found that wood density variations in conifers growing under cold-limited environment result from the adjustment of cell wall thickness (CWT) to temperature. Additionally, it is known that intra-annual density fluctuations (IADFs) are formed in response to precipitation after the summer drought. Although IADFs are frequent in Mediterranean conifers no study has yet been conducted to determine if these structures result from the adjustment of lumen diameter (LD) or CWT to soil water availability. Our main objective is to investigate the intra-ring variation of wood anatomical features (LD and CWT) in Pinus pinaster Ait. growing under a water-limited environment. We compared the tracheidograms of LD and CWT for the years 2010–2013 in P. pinaster growing in the west coast of Portugal. Our results suggest a close association between LD and soil moisture content along the growing season, reinforcing the role of water availability in determining tracheid size. Compared with CWT, LD showed a higher intra- and inter-annual variability suggesting its strong adjustment value to variations in water availability. The formation of a latewood IADF appears to be predisposed by higher rates of cell production in spring and triggered by early autumn precipitation. Our findings reinforce the crucial role of water availability on cambial activity and wood formation in Mediterranean conifers, and emphasize the high plasticity of wood anatomical features under Mediterranean climate. PMID:26305893
Carvalho, Ana; Nabais, Cristina; Vieira, Joana; Rossi, Sergio; Campelo, Filipe
2015-01-01
The formation of wood results from cambial activity and its anatomical properties reflect the variability of environmental conditions during the growing season. Recently, it was found that wood density variations in conifers growing under cold-limited environment result from the adjustment of cell wall thickness (CWT) to temperature. Additionally, it is known that intra-annual density fluctuations (IADFs) are formed in response to precipitation after the summer drought. Although IADFs are frequent in Mediterranean conifers no study has yet been conducted to determine if these structures result from the adjustment of lumen diameter (LD) or CWT to soil water availability. Our main objective is to investigate the intra-ring variation of wood anatomical features (LD and CWT) in Pinus pinaster Ait. growing under a water-limited environment. We compared the tracheidograms of LD and CWT for the years 2010-2013 in P. pinaster growing in the west coast of Portugal. Our results suggest a close association between LD and soil moisture content along the growing season, reinforcing the role of water availability in determining tracheid size. Compared with CWT, LD showed a higher intra- and inter-annual variability suggesting its strong adjustment value to variations in water availability. The formation of a latewood IADF appears to be predisposed by higher rates of cell production in spring and triggered by early autumn precipitation. Our findings reinforce the crucial role of water availability on cambial activity and wood formation in Mediterranean conifers, and emphasize the high plasticity of wood anatomical features under Mediterranean climate.
Haines, Seth S.; Varela, Brian; Hawkins, Sarah J.; Gianoutsos, Nicholas J.; Tennyson, Marilyn E.
2017-01-01
The U.S. Geological Survey (USGS) has conducted an assessment of water and proppant requirements, and water production volumes, associated with possible future production of undiscovered petroleum resources in the Bakken and Three Forks Formations, Williston Basin, USA. This water and proppant assessment builds directly from the 2013 USGS petroleum assessment for the Bakken and Three Forks Formations, and it has been conducted using a new water and proppant assessment methodology that builds from the established USGS methodology for assessment of undiscovered petroleum in continuous reservoirs. We determined the assessment input values through extensive analysis of available data on per-well water and proppant use for hydraulic fracturing, including trends over time and space. We determined other assessment inputs through analysis of regional water-production trends.
A toolkit for determining historical eco-hydrological interactions
NASA Astrophysics Data System (ADS)
Singer, M. B.; Sargeant, C. I.; Evans, C. M.; Vallet-Coulomb, C.
2016-12-01
Contemporary climate change is predicted to result in perturbations to hydroclimatic regimes across the globe, with some regions forecast to become warmer and drier. Given that water is a primary determinant of vegetative health and productivity, we can expect shifts in the availability of this critical resource to have significant impacts on forested ecosystems. The subject is particularly complex in environments where multiple sources of water are potentially available to vegetation and which may also exhibit spatial and temporal variability. To anticipate how subsurface hydrological partitioning may evolve in the future and impact overlying vegetation, we require well constrained, historical data and a modelling framework for assessing the dynamics of subsurface hydrology. We outline a toolkit to retrospectively investigate dynamic water use by trees. We describe a synergistic approach, which combines isotope dendrochronology of tree ring cellulose with a biomechanical model, detailed climatic and isotopic data in endmember waters to assess the mean isotopic composition of source water used in annual tree rings. We identify the data requirements and suggest three versions of the toolkit based on data availability. We present sensitivity analyses in order to identify the key variables required to constrain model predictions and then develop empirical relationships for constraining these parameters based on climate records. We demonstrate our methodology within a Mediterranean riparian forest site and show how it can be used along with subsurface hydrological modelling to validate source water determinations, which are fundamental to understanding climatic fluctuations and trends in subsurface hydrology. We suggest that the utility of our toolkit is applicable in riparian zones and in a range of forest environments where distinct isotopic endmembers are present.
Fisher, Michael B; Shields, Katherine F; Chan, Terence U; Christenson, Elizabeth; Cronk, Ryan D; Leker, Hannah; Samani, Destina; Apoya, Patrick; Lutz, Alexandra; Bartram, Jamie
2015-10-01
Safe drinking water is critical to human health and development. In rural sub-Saharan Africa, most improved water sources are boreholes with handpumps; studies suggest that up to one third of these handpumps are nonfunctional at any given time. This work presents findings from a secondary analysis of cross-sectional data from 1509 water sources in 570 communities in the rural Greater Afram Plains (GAP) region of Ghana; one of the largest studies of its kind. 79.4% of enumerated water sources were functional when visited; in multivariable regressions, functionality depended on source age, management, tariff collection, the number of other sources in the community, and the district. A Bayesian network (BN) model developed using the same data set found strong dependencies of functionality on implementer, pump type, management, and the availability of tools, with synergistic effects from management determinants on functionality, increasing the likelihood of a source being functional from a baseline of 72% to more than 97% with optimal management and available tools. We suggest that functionality may be a dynamic equilibrium between regular breakdowns and repairs, with management a key determinant of repair rate. Management variables may interact synergistically in ways better captured by BN analysis than by logistic regressions. These qualitative findings may prove generalizable beyond the study area, and may offer new approaches to understanding and increasing handpump functionality and safe water access.
Geology and ground-water resources of Dane County, Wisconsin
Cline, Denzel R.
1965-01-01
The purpose of the ground-water investigation of Dane County, Wis., was to determine the occurrence, movement, quantity, quality, and availability of ground water in the unconsolidated deposits and the underlying bedrock. The relationships between ground water and surface water were studied in general in Dane County and in detail in the Madison metropolitan area. An analysis was made of the hydrologic system of the Yahara River valley and of the effects of ground-water pumpage on that system.
NASA Astrophysics Data System (ADS)
Finger, D.; Hugentobler, A.; Huss, M.; Voinesco, A.; Wernli, H.; Fischer, D.; Weber, E.; Jeannin, P.-Y.; Kauzlaric, M.; Wirz, A.; Vennemann, T.; Hüsler, F.; Schädler, B.; Weingartner, R.
2013-03-01
Glaciers all over the world are expected to continue to retreat due to the global warming throughout the 21st century. Consequently, future seasonal water availability might become scarce once glacier areas have declined below a certain threshold affecting future water management strategies. Particular attention should be paid to glaciers located in a karstic environment, as parts of the melt water can be drained by souterrain karst systems. In this study tracer experiments, karst modeling and glacier melt modeling are combined in order to identify flow paths in a high alpine, glacierized, karstic environment (Glacier de la Plaine Morte, Switzerland) and to investigate current and predict future downstream water availability. Flow paths through the karst underground were determined with natural and fluorescent tracers. Subsequently, tracer results and geologic information were assembled in a karst model. Finally, glacier melt projections driven with a climate scenario were performed to discuss future water availability in the area surrounding the glacier. The results suggest that during late summer glacier melt water is rapidly drained through well-developed channels at the glacier bottom to the north of the glacier, while during low flow season melt water enters into the karst and is drained to the south. Climate change projections reveal that by the end of the century glacier melt will be significantly reduced in the summer, jeopardizing water availability in glacier-fed karst springs.
Availability of ground water in the middle Merrimack River basin, central and southern New Hampshire
Cotton, J.E.
1976-01-01
Sufficient amounts of water to supply single family homes are available from the bedrock aquifer nearly everywhere in the middle Merrimack River basin in central and southern New Hampshire. Relatively this and narrow, unconsolidated aquifers of sand or sand and gravel commonly capable of yielding more than 200 gallons per minute to properly located and constructed wells are found only in major stream valleys. The map provides a preliminary assessment of the availability of ground water in the basin, as determined by estimating the capability of the aquifers to store and transmit water. On the map, aquifers are rated as having high, medium, or low potential to yield water. Ground water in the middle Merrimack River basin is generally of good chemical quality. Most of it is clear and colorless, contains no suspended matter and practically no bacteria, water may be affected by land-use practices. Degradation of water quality may occur in unsewered residential and village areas, near solid-waste-disposal sites, agricultural land, and major highways. (Woodard-USGS)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bloomquist, R.G.; Wegman, S.
1998-04-01
The purpose of the present work was to determine if existing heat pump systems based on municipal water systems meet existing water quality standards, to analyze water that has passed through a heat pump or heat exchanger to determine if corrosion products can be detected, to determine residual chlorine levels in municipal waters on the inlet as well as the outlet side of such installations, to analyses for bacterial contaminants and/or regrowth due to the presence of a heat pump or heat exchanger, to develop and suggest criteria for system design and construction, to provide recommendations and specifications for materialmore » and fluid selection, and to develop model rules and regulations for the installation, operation, and monitoring of new and existing systems. In addition, the Washington State University (WSU) has evaluated availability of computer models that would allow for water system mapping, water quality modeling and system operation.« less
How Much Water Trees Access and How It Determines Forest Response to Drought
NASA Astrophysics Data System (ADS)
Berdanier, A. B.; Clark, J. S.
2015-12-01
Forests are transformed by drought as water availability drops below levels where trees of different sizes and species can maintain productivity and survive. Physiological studies have provided detailed understanding of how species differences affect drought vulnerability but they offer almost no insights about the amount of water different trees can access beyond general statements about rooting depth. While canopy architecture provides strong evidence for light availability aboveground, belowground moisture availability remains essentially unknown. For example, do larger trees always have greater access to soil moisture? In temperate mixed forests, the ability to access a large soil moisture pool could minimize damage during drought events and facilitate post-drought recovery, potentially at the expense of neighboring trees. We show that the pool of accessible soil moisture can be estimated for trees with data on whole-plant transpiration and that this data can be used to predict water availability for forest stands. We estimate soil water availability with a Bayesian state-space model based on a simple water balance, where cumulative depressions in water use below potential transpiration indicate soil resource depletion. We compare trees of different sizes and species, extend these findings to the entire stand, and connect them to our recent research showing that tree survival after drought depends on post-drought growth recovery and local moisture availability. These results can be used to predict competitive abilities for soil water, understand ecohydrological variation within stands, and identify trees that are at risk of damage from future drought events.
Northern part, Ten Mile and Taunton River basins
Williams, John R.; Willey, Richard E.
1967-01-01
This report is one of two prepared by the Geological Survey for the Water Resources Commission. The principal purpose of this report is to make available the basic data on which the other, a map showing availability of ground water, is based. This basic-data report also can be used by engineers, planners, and others interested in or responsible for water-resources planning to determine the materials to be encountered (tables 3 and 4) and the yields which may be obtained from wells and test holes (tables 1 and 2) in the stratified sand and gravel that are the principal source of ground water and in bedrock. Partial and complete chemical analyses (tables 7 and 8) of these test holes and of some privately-owned wells provide information on the general quality of the water for domestic and other uses. A tabulation of existing municipal supplies, their capacity, production (table 5), and chemical quality of the water (table 6) may be used for regional planning purposes. Water-level measurements (figure 1) can be used to determine the annual fluctuations of the water table in certain types of materials. Seismic work (table 9) in the Canoe River valley, Norton, and test drilling with a power augur (tables 2 and 4) were done for the Geological Survey as part of the investigation.
DETERMINATION OF KOW VALUES FOR A SERIES OF ARYL GLUCURONIDES
An important perameter in toxicokinetic modeling is the octanol/water partition coefficient (Kow). This parameter has often been used to predict the accumulation of contaminants from water to fish (Klamer and Beekman 1995); however, few Kow values are available for modeling the b...
Reliability-Productivity Curve, a Tool for Adaptation Measures Identification
NASA Astrophysics Data System (ADS)
Chávez-Jiménez, A.; Granados, A.; Garrote, L. M.
2015-12-01
Due to climate change effects, water scarcity problems would intensify in several regions. These problems are going to impact negatively in the water low-priority demands, since these will be reduced in favor of those with high-priority. An example would be the reduction of agriculture water resources in favor of the urban ones. Then, it is important the evaluation of adaptation measures for a better water resources management. An important tool to face this challenge is the economic valuation of the water demands' impact within a water resources system. In agriculture this valuation is usually performed through the water productivity evaluation. The water productivity evaluation requires detailed information regarding the different crops like the applied technology, the agricultural supplies management, the water availability, etc. This is a restriction for an evaluation at basin scale due to the difficulty of gathers this level of detailed information. Besides, only the water availability is taken into account, but not the period when the water is distributed (i.e. water resources reliability). Water resources reliability is one of the most important variables in water resources management. This research proposes a methodology to determine the agriculture water productivity, using as variables the crops information, the crops price, the water resources availability, and the water resources reliability, at a basin scale. This methodology would allow identifying general water resources adaptation measures, providing the basis for further detailed studies in critical regions.
NASA Astrophysics Data System (ADS)
Roy, A.; Inamdar, A. B.
2016-12-01
Major part of Godavari River Basin is intensely drought prone and climate vulnerable in the Western Maharashtra State, India. The economy of the state depends on the agronomic productivity of this region. So, it is necessary to regulate the effects of existing and upcoming hydro-meteorological advances in various strata. This study investigates and maps the surface water resources availability and vegetation, their decadal deviations with multi-temporal LANDSAT images; and finally quantifies the agricultural adaptations. This work involves the utilization of Remote Sensing and GIS with Hydrological modeling. First, climatic trend analysis is carried out with NCEP dataset. Then, multi-temporal LANDSAT images are classified to determine the decadal LULC changes and correlated to the community level hydrological demand. Finally, NDVI, NDWI and SWAT model analysis are accomplished to determine irrigated and non-irrigated cropping area for identifying the agricultural adaptations. The analysis shows that the mean value of annual and monsoon rainfall is significantly decreasing, whereas the mean value of annual and summer temperature is increasing significantly and the winter temperature is decreasing. The analysis of LANDSAT images shows that the surface water availability is highly dependent on climatic conditions. Barren-lands are most dynamic during the study period followed by, vegetation, and water bodies. The spatial extent of barren-lands is increased drastically during the climate vulnerable years replacing the vegetation and surface water bodies. Hence, the barren lands are constantly increasing and the vegetation cover is linearly decreasing, whereas the water extent is changing either way in a random fashion. There appears a positive correlation between surface water and vegetation occurrence; as they are fluctuating in a similar fashion in all the years. The vegetation cover is densely replenished around the dams and natural water bodies which serve as the water supply stations for the irrigation purposes. Moreover, there is a shift to non-irrigated and less water demanding crops, from more water demanding crops, which is a conspicuous adaptation. Hence, the study shows there are alteration in meteorological predictors, land cover, agricultural practices and surface water availability.
NASA Technical Reports Server (NTRS)
Hu, Hua; Liu, W. Timothy
1999-01-01
Water vapor and precipitation are two important parameters confining the hydrological cycle in the atmosphere and over the ocean surface. In the extratropical areas, due to variations of midlatitude storm tracks and subtropical jetstreams, water vapor and precipitation have large variability. Recently, a concept of water recycling rate defined previously by Chahine et al. (GEWEX NEWS, August, 1997) has drawn increasing attention. The recycling rate of moisture is calculated as the ratio of precipitation to total precipitable water (its inverse is the water residence time). In this paper, using multi-sensor spacebased measurements we will study the role of sea surface temperature and ocean surface wind in determining the water recycling rate over oceans and coastal lands. Response of water recycling rate in midlatitudes to the El Nino event will also be discussed. Sea surface temperature data are derived from satellite observations from the Advanced Very High Resolution Radiometer (AVHRR) blended with in situ measurements, available for the period 1982-1998. Global sea surface wind observations are obtained from spaceborne scatterometers aboard on the European Remote-Sensing Satellite (ERS1 and 2), available for the period 1991-1998. Global total precipitable water provided by the NASA Water Vapor Project (NVAP) is available for the period 1988-1995. Global monthly mean precipitation provided by the Global Precipitation Climatology Project (GPCP) is available for the period 1987-1998.
Huckins, J.N.; Petty, J.D.; Orazio, C.E.; Lebo, J.A.; Clark, R.C.; Gibson, V.L.; Gala, W.R.; Echols, K.R.
1999-01-01
The use of lipid-containing semipermeable membrane devices (SPMDs) is becoming commonplace, but very little sampling rate data are available for the estimation of ambient contaminant concentrations from analyte levels in exposed SPMDs. We determined the aqueous sampling rates (R(s)s; expressed as effective volumes of water extracted daily) of the standard (commercially available design) 1-g triolein SPMD for 15 of the priority pollutant (PP) polycyclic aromatic hydrocarbons (PAHs) at multiple temperatures and concentrations. Under the experimental conditions of this study, recovery- corrected R(s) values for PP PAHs ranged from ???1.0 to 8.0 L/d. These values would be expected to be influenced by significant changes (relative to this study) in water temperature, degree of biofouling, and current velocity- turbulence. Included in this paper is a discussion of the effects of temperature and octanol-water partition coefficient (K(ow)); the impacts of biofouling and hydrodynamics are reported separately. Overall, SPMDs responded proportionally to aqueous PAH concentrations; i.e., SPMD R(s) values and SPMD-water concentration factors were independent of aqueous concentrations. Temperature effects (10, 18, and 26 ??C) on Rs values appeared to be complex but were relatively small.The use of lipid-containing semipermeable membrane devices (SPMDs) is becoming commonplace, but very little sampling rate data are available for the estimation of ambient contaminant concentrations from analyte levels in exposed SPMDs. We determined the aqueous sampling rates (Rss; expressed as effective volumes of water extracted daily) of the standard (commercially available design) 1-g triolein SPMD for 15 of the priority pollutant (PP) polycyclic aromatic hydrocarbons (PAHs) at multiple temperatures and concentrations. Under the experimental conditions of this study, recovery-corrected Rs values for PP PAHs ranged from ???1.0 to 8.0 L/d. These values would be expected to be influenced by significant changes (relative to this study) in water temperature, degree of biofouling, and current velocity-turbulence. Included in this paper is a discussion of the effects of temperature and octanol-water partition coefficient (KOW); the impacts of biofouling and hydrodynamics are reported separately. Overall, SPMDs responded proportionally to aqueous PAH concentrations; i.e., SPMD RS values and SPMD-water concentration factors were independent of aqueous concentrations. Temperature effects (10, 18, and 26??C) on RS values appeared to be complex but were relatively small.
Effects of depth and crayfish size on predation risk and foraging profitability of a lotic crayfish
Flinders, C.A.; Magoulick, D.D.
2007-01-01
We conducted field surveys and experiments to determine whether observed distributions of crayfish among habitats were influenced by differential resource availability, foraging profitability, and predation rates and whether these factors differed with crayfish size and habitat depth. We sampled available food resources (detritus and invertebrates) and shelter as rock substrate in deep (>50 cm) and shallow (<30 cm) habitats. We used an enclosure-exclosure experiment to examine the effects of water depth and crayfish size on crayfish biomass and survival, and to determine whether these factors affected silt accrual, algal abundance (chlorophyll a [chl a]), and detritus and invertebrate biomass (g ash-free dry mass) differently from enclosures without crayfish. We conducted tethering experiments to assess predation on small (13-17 mm carapace length [CL]) and large (23-30 mm CL) Orconectes marchandi and to determine whether predation rates differed with water depth. Invertebrate biomass was significantly greater in shallow water than in deep water, whereas detritus biomass did not differ significantly between depths. Cobble was significantly more abundant in shallow than in deep water. Depth and crayfish size had a significant interactive effect on change in size of enclosed crayfish when CL was used as a measure of size but not when biomass was used as a measure of size. CL of small crayfish increased significantly more in enclosures in shallow than in deep water, but CL of large crayfish changed very little at either depth. Silt, chl a, and detritus biomass were significantly lower on tiles in large- than in small- and no-crayfish enclosures, and invertebrate biomass was significantly lower in large- than in no-crayfish enclosures. Significantly more crayfish were consumed in deep than in shallow water regardless of crayfish size. Our results suggest that predation and resource availability might influence the depth distribution of small and large crayfish. Small crayfish grew faster in shallow habitats where they might have had a fitness advantage caused by high prey availability and reduced predation risk. Size-dependent reduction of silt by crayfish might influence benthic habitats where large crayfish are abundant. ?? 2007 by The North American Benthological Society.
Manganese in Madison's drinking water.
Schlenker, Thomas; Hausbeck, John; Sorsa, Kirsti
2008-12-01
Public concern over events of manganese-discolored drinking water and the potential for adverse health effects from exposure to excess manganese reached a high level in 2005. In response, Public Health Madison Dane County, together with the Madison Water Utility, conceived and implemented a public health/water utility strategy to quantify the extent of the manganese problem, determine the potential for adverse human health effects, and communicate these findings to the community. This strategy included five basic parts: taking an inventory of wells and their manganese levels, correlating manganese concentration with turbidity, determining the prevalence and distribution of excess manganese in Madison households, reviewing the available scientific literature, and effectively communicating our findings to the community. The year-long public health/water utility strategy successfully resolved the crisis of confidence in the safety of Madison's drinking water.
HYDROLOGICAL IMPACTS OF WOODY PLANT ENCROACHMENT IN ARID AND SEMIARID GRASSLANDS
Woody plants may be able to access deeper groundwater for year-round transpiration and thus consume more water than grasses, affecting recharge, soil moisture and runoff. Amount of water available to plants from precipitation is determined in part by nfiltration rates into...
78 FR 20343 - Proposed Flood Hazard Determinations
Federal Register 2010, 2011, 2012, 2013, 2014
2013-04-04
... panels of experts in hydrology, hydraulics, and other pertinent sciences established to review..., Indiana, and Incorporated Areas Maps Available for Inspection Online at: http://www.in.gov/dnr/water/6674..., Leavenworth, IN 47137. Town of Marengo Town Hall, 117 East Water Street, Marengo, IN 47140. Town of Milltown...
77 FR 58560 - Proposed Flood Hazard Determinations
Federal Register 2010, 2011, 2012, 2013, 2014
2012-09-21
... resolution process. SRPs are independent panels of experts in hydrology, hydraulics, and other pertinent.../dnr/water/6497.htm City of Tipton Tipton County Courthouse, 101 East Jefferson Street, Tipton, IN... Incorporated Areas Maps Available for Inspection Online at: http://www.in.gov/dnr/water/6648.htm City of...
NASA Astrophysics Data System (ADS)
Kaune, Alexander; López, Patricia; Werner, Micha; de Fraiture, Charlotte
2017-04-01
Hydrological information on water availability and demand is vital for sound water allocation decisions in irrigation districts, particularly in times of water scarcity. However, sub-optimal water allocation decisions are often taken with incomplete hydrological information, which may lead to agricultural production loss. In this study we evaluate the benefit of additional hydrological information from earth observations and reanalysis data in supporting decisions in irrigation districts. Current water allocation decisions were emulated through heuristic operational rules for water scarce and water abundant conditions in the selected irrigation districts. The Dynamic Water Balance Model based on the Budyko framework was forced with precipitation datasets from interpolated ground measurements, remote sensing and reanalysis data, to determine the water availability for irrigation. Irrigation demands were estimated based on estimates of potential evapotranspiration and coefficient for crops grown, adjusted with the interpolated precipitation data. Decisions made using both current and additional hydrological information were evaluated through the rate at which sub-optimal decisions were made. The decisions made using an amended set of decision rules that benefit from additional information on demand in the districts were also evaluated. Results show that sub-optimal decisions can be reduced in the planning phase through improved estimates of water availability. Where there are reliable observations of water availability through gauging stations, the benefit of the improved precipitation data is found in the improved estimates of demand, equally leading to a reduction of sub-optimal decisions.
Wild, Emily C.; Nimiroski, Mark T.
2004-01-01
In 1988, the Pawcatuck Basin (302.4 square miles) in southern Rhode Island (245.3 square miles) and southeastern Connecticut (57.12 square miles) was defined as a sole-source aquifer for 14 towns in southern Rhode Island and 4 towns in southeastern Connecticut. To determine water use and availability, the six subbasins in the Pawcatuck Basin were delineated on the basis of the surface- and ground-water system drainage areas. From 1995 through 1999, five major water suppliers in the basin withdrew an average of 6.768 million gallons per day from the aquifers. The estimated water withdrawals from minor water suppliers during the study period were 0.099 million gallons per day. Self-supplied domestic, industrial, commercial, and agricultural withdrawals from the basin averaged 4.386 million gallons per day. Water use in the basin averaged 7.401 million gallons per day. The average return flow in the basin was 7.855 million gallons per day, which included effluent from permitted facilities and self-disposed water users. The PART program, a computerized hydrographseparation application, was used for five selected index streamgaging stations to determine water availability on the basis of the 75th, 50th, and 25th percentiles of the total base flow, the base flow minus the 7-day, 10-year flow criteria, and the base flow minus the Aquatic Base Flow criteria at the index stations. The differences in the surface- and ground-water system drainage areas in the summer were applied to the water availability calculated at the index stations and subbasins. The base-flow contributions from sand and gravel deposits at the index stations were computed for June, July, August, and September, and applied to the percentage of surficial deposits at each index station. The base-flow contributions were converted to a per unit area at the station for the till, and for the sand and gravel deposits, and applied to the subbasins. The statistics used to estimate the gross yield of base flow, as well as subtracting out the two low-flow criteria, resulted in various wateravailability values at each index station, which were present in the subbasin after applying the per unit area rates from the index station. The results from the Chipuxet and Arcadia streamgaging stations were lowest in September at the 75th and 25th percentiles, and August flows were lowest for the summer at the 50th percentile. For the other three index stations, September flows were the lowest for the summer. Because water withdrawals and use are greater during the summer than other times of the year, water availability in June, July, August, and September was assessed and compared to water withdrawals in the basin and subbasins. The ratios were calculated by using the water-availability flow scenarios at the 75th, 50th, and 25th percentiles for the subbasins, which are based on total water available from base-flow contributions from till deposits and sand and gravel deposits in the subbasins. For the study period, the withdrawals in August were higher than the other summer months. The ratios were close to one in August for the estimated gross yield and 7-day, 10-year flow criterion, and were close to one in September for the estimated Aquatic Base Flow criterion water-availability scenarios in the Pawcatuck Basin. The closer the ratio is to one, the closer the withdrawals are to the estimated water available, and the net water available decreases. To determine the effects of streamflow depletion from continuous water withdrawals, the program STRMDEPL was used to simulate public wells and well fields at a constant pumping rate based on the 1999 summer average for each withdrawal, over a period of 180 days. The streamflow depletion was 86, 95, 93, 96, and 98 percent at 30 days for Kingston wells 1 and 2, Westerly well fields 1 and 2, and well 3, respectively. A long-term hydrologic budget was calculated for the Pawcatuck Basin to identify and assess the basin and subbasin inflow and outflows. The water withdrawals and return flows used in the budget were from 1995 through 1999. For the hydrologic budget, it was assumed that inflow equals outflow, which resulted in 723.1 million gallons per day in the basin. The estimated inflows from precipitation and water return flow were 99 and 1 percent in the basin, respectively. The estimated outflows from evapotranspiration, streamflow, and water withdrawals were 43, 56, and 1 percent, respectively.
Rodier, Marion; Li, Qingfeng; Berg, Rolf Willestofte; Bjerrum, Niels Janniksen
2016-07-01
A method to determine the water vapor pressure over a corrosive substance was developed and tested with 85.5 ± 0.4% phosphoric acid. The water vapor pressure was obtained at a range of temperatures from ∼25 ℃ to ∼200 ℃ using Raman spectrometry. The acid was placed in an ampoule and sealed with a reference gas (either hydrogen or methane) at a known pressure (typically ∼0.5 bar). By comparing the Raman signals from the water vapor and the references, the water pressure was determined as a function of temperature. A considerable amount of data on the vapor pressure of phosphoric acid are available in the literature, to which our results could successfully be compared. A record value of the vapor pressure, 3.40 bar, was determined at 210 ℃. The method required a determination of the precise Raman scattering ratios between the substance, water, and the used reference gas, hydrogen or methane. In our case the scattering ratios between water and reference ν1 Q-branches were found to be 1.20 ± 0.03 and 0.40 ± 0.02 for H2 and CH4, respectively. © The Author(s) 2016.
Knowles, D.B.
1955-01-01
The objective of the Ground Water Branch is to evaluate the occurrence, availability, and quality of ground water. The science of ground-water hydrology is applied toward attaining that goal. Although many ground-water investigations are of a qualitative nature, quantitative studies are necessarily an integral component of the complete evaluation of occurrence and availability. The worth of an aquifer as a fully developed source of water depends largely on two inherent characteristics: its ability to store, and its ability to transmit water. Furthermore, quantitative knowledge of these characteristics facilitates measurement of hydrologic entities such as recharge, leakage, evapotranspiration, etc. It is recognized that these two characteristics, referred to as the coefficients of storage and transmissibility, generally provide the very foundation on which quantitative studies are constructed. Within the science of ground-water hydrology, ground-water hydraulics methods are applied to determine these constats from field data.
Arvin, D.V.
1992-01-01
The feasibility of using time totalizers for determining water use was investigated by observing seven vibration time totalizers (VTT's) mounted at five sites. None of the units exhibited adverse effects from the heat, precipitation, or humidity associated with Indiana summers. One VTT was mounted at a public water-supply site where inductive time-totalizer measurements were available for comparison. The VTT agreed within 8 hours of the inductive time totalizer after 2,340 hours of pump operation. There were no mechanical prpblems with the VTT units used in this study.
NASA Astrophysics Data System (ADS)
Finger, D.; Hugentobler, A.; Huss, M.; Voinesco, A.; Wernli, H.; Fischer, D.; Weber, E.; Jeannin, P.-Y.; Kauzlaric, M.; Wirz, A.; Vennemann, T.; Hüsler, F.; Schädler, B.; Weingartner, R.
2013-08-01
Glaciers all over the world are expected to continue to retreat due to the global warming throughout the 21st century. Consequently, future seasonal water availability might become scarce once glacier areas have declined below a certain threshold affecting future water management strategies. Particular attention should be paid to glaciers located in a karstic environment, as parts of the meltwater can be drained by underlying karst systems, making it difficult to assess water availability. In this study tracer experiments, karst modeling and glacier melt modeling are combined in order to identify flow paths in a high alpine, glacierized, karstic environment (Glacier de la Plaine Morte, Switzerland) and to investigate current and predict future downstream water availability. Flow paths through the karst underground were determined with natural and fluorescent tracers. Subsequently, geologic information and the findings from tracer experiments were assembled in a karst model. Finally, glacier melt projections driven with a climate scenario were performed to discuss future water availability in the area surrounding the glacier. The results suggest that during late summer glacier meltwater is rapidly drained through well-developed channels at the glacier bottom to the north of the glacier, while during low flow season meltwater enters into the karst and is drained to the south. Climate change projections with the glacier melt model reveal that by the end of the century glacier melt will be significantly reduced in the summer, jeopardizing water availability in glacier-fed karst springs.
Evaluation of selected surface-water-quality stations in Wyoming
Rucker, S.J.; DeLong, L.L.
1987-01-01
The U.S. Geological Survey, in cooperation with the Wyoming Department of Agriculture, has conducted a surface-water-quality program in Wyoming since 1965. The purpose has been to determine the chemical quality of the water in terms of the major dissolved constituents (salinity). Changing agricultural techniques and energy development have stimulated a need for an expanded program involving additional types of data. This report determines the adequacy of the data collected thus far to describe the chemical quality. The sampling program was evaluated by determining how well the data describe the dissolved-solids load of the streams. Monthly mean loads were estimated at 16 stations throughout the network where daily streamflow and daily specific conductance were available. Monthly loads were then compared with loads estimated from daily streamflow and data derived from analyses of samples collected on a monthly basis at these same stations. Agreement was good. Solute-load hydrographs were constructed for 37 stations and from some reaches where streamflow records were available. Because stations where no discharge records are available are not amenable to this type of analysis, data collected at these stations are of limited usefulness. This report covers analyses of data for all qualifying sites in Wyoming except those in the Green River Basin, which were analyzed in U.S. Geological Survey Water Resources Investigations 77-103. The salinity in most of the streams evaluated is adequately described by the data collected. Reduced sampling is feasible, and time and money can be diverted to collecting other data. (USGS)
Economic Impact of Water Allocation on Agriculture in the Lower Chattahoochee River Basin
NASA Technical Reports Server (NTRS)
Limaye, Ashutosh S.; Paudel, Krishna P.; Musleh, Fuad; Cruise, James F.; Hatch, L. Upton
2004-01-01
The relative value of irrigation water was assessed for three important crops (corn, cotton, and peanuts) grown in the southeastern United States. A decision tool was developed with the objective of allocating limited available water among competing crops in a manner that would maximize the economic returns to the producers. The methodology was developed and tested for a hypothetical farm located in Henry County, Alabama in the Chattahoochee river basin. Crop yield - soil moisture response functions were developed using Monte Carlo simulated data for cotton, corn, and peanuts. A hydrologic model was employed to simulate runoff over the period of observed rainfall the county to provide inflows to storage facilities that could be used as constraints for the optimal allocation of the available water in the face of the uncertainty of future rainfall and runoff. Irrigation decisions were made on a weekly basis during the critical water deficit period in the region. An economic optimization model was employed with the crop responses, and soil moisture functions to determine the optimum amount of water place on each crop subject to the amount of irrigation water availability and climatic uncertainty. The results indicated even small amounts of irrigation could significantly benefit farmers in the region if applied judiciously. A weekly irrigation sequence was developed that maintained the available water on the crops that exhibited the most significant combination of water sensitivity and cash value.
NASA Astrophysics Data System (ADS)
Le, A.; Pricope, N. G.
2015-12-01
Projections indicate that increasing population density, food production, and urbanization in conjunction with changing climate conditions will place stress on water resource availability. As a result, a holistic understanding of current and future water resource distribution is necessary for creating strategies to identify the most sustainable means of accessing this resource. Currently, most water resource management strategies rely on the application of global climate predictions to physically based hydrologic models to understand potential changes in water availability. However, the need to focus on understanding community-level social behaviors that determine individual water usage is becoming increasingly evident, as predictions derived only from hydrologic models cannot accurately represent the coevolution of basin hydrology and human water and land usage. Models that are better equipped to represent the complexity and heterogeneity of human systems and satellite-derived products in place of or in conjunction with historic data significantly improve preexisting hydrologic model accuracy and application outcomes. We used a novel agent-based sociotechnical model that combines the Soil and Water Assessment Tool (SWAT) and Agent Analyst and applied it in the Nzoia Basin, an area in western Kenya that is becoming rapidly urbanized and industrialized. Informed by a combination of satellite-derived products and over 150 household surveys, the combined sociotechnical model provided unique insight into how populations self-organize and make decisions based on water availability. In addition, the model depicted how population organization and current management alter water availability currently and in the future.
Hagihara, Rie; Jones, Rhondda E; Sobtzick, Susan; Cleguer, Christophe; Garrigue, Claire; Marsh, Helene
2018-01-01
The probability of an aquatic animal being available for detection is typically <1. Accounting for covariates that reduce the probability of detection is important for obtaining robust estimates of the population abundance and determining its status and trends. The dugong (Dugong dugon) is a bottom-feeding marine mammal and a seagrass community specialist. We hypothesized that the probability of a dugong being available for detection is dependent on water depth and that dugongs spend more time underwater in deep-water seagrass habitats than in shallow-water seagrass habitats. We tested this hypothesis by quantifying the depth use of 28 wild dugongs fitted with GPS satellite transmitters and time-depth recorders (TDRs) at three sites with distinct seagrass depth distributions: 1) open waters supporting extensive seagrass meadows to 40 m deep (Torres Strait, 6 dugongs, 2015); 2) a protected bay (average water depth 6.8 m) with extensive shallow seagrass beds (Moreton Bay, 13 dugongs, 2011 and 2012); and 3) a mixture of lagoon, coral and seagrass habitats to 60 m deep (New Caledonia, 9 dugongs, 2013). The fitted instruments were used to measure the times the dugongs spent in the experimentally determined detection zones under various environmental conditions. The estimated probability of detection was applied to aerial survey data previously collected at each location. In general, dugongs were least available for detection in Torres Strait, and the population estimates increased 6-7 fold using depth-specific availability correction factors compared with earlier estimates that assumed homogeneous detection probability across water depth and location. Detection probabilities were higher in Moreton Bay and New Caledonia than Torres Strait because the water transparency in these two locations was much greater than in Torres Strait and the effect of correcting for depth-specific detection probability much less. The methodology has application to visual survey of coastal megafauna including surveys using Unmanned Aerial Vehicles.
EPA announced the availability of the final report, Nanomaterial Case Studies: Nanoscale Titanium Dioxide in Water Treatment and in Topical Sunscreen. This report is a starting point to determine what is known and what needs to be known about selected nanomaterials as par...
USDA-ARS?s Scientific Manuscript database
Hydrologic and water quality models are very sensitive to input parameter values, especially precipitation input data. With several different sources of precipitation data now available, it is quite difficult to determine which source is most appropriate under various circumstances. We used several ...
7 CFR 1437.104 - Assigned production.
Code of Federal Regulations, 2010 CFR
2010-01-01
...) Irrigation equipment is not capable of supplying adequate water to sustain the expected production of a... practice is not used. (7) For normal irrigated annual and biennial crops, the supply of available water at... determining losses under this section, assigned production will be used to offset the loss of production when...
Determining Which Dispersants Will Be Effective In Future Deepwater Oil Spills
Deepwater spills result in oil distributed from deep in the water column to the water surface. The objective of this study was to test eight of the available dispersants (including Corexit 9500A, which was used extensively on the 2010 Deepwater Horizon Spill) on South Louisiana C...
78 FR 28888 - Proposed Flood Hazard Determinations
Federal Register 2010, 2011, 2012, 2013, 2014
2013-05-16
... resolution process. SRPs are independent panels of experts in hydrology, hydraulics, and other pertinent.../dnr/water/6670.htm City of Oakland City City Hall, 210 East Washington Street, Oakland City, IN 47660... Areas Maps Available for Inspection Online at: http://www.in.gov/dnr/water/6472.htm City of Martinsville...
77 FR 29678 - Proposed Flood Hazard Determinations
Federal Register 2010, 2011, 2012, 2013, 2014
2012-05-18
... resolution process. SRPs are independent panels of experts in hydrology, hydraulics, and other pertinent..., and Incorporated Areas Maps Available for Inspection Online at: http://www.in.gov/dnr/water/7293.htm... Online at: http://www.dnr.sc.gov/water/flood/comaps.html City of Manning 29 West Boyce Street, Manning...
Gortan, Emmanuelle; Nardini, Andrea; Gascó, Antonio; Salleo, Sebastiano
2009-04-01
Leaf hydraulic conductance (Kleaf) is known to be an important determinant of plant gas exchange and photosynthesis. Little is known about the long-term impact of different environmental factors on the hydraulic construction of leaves and its eventual consequences on leaf gas exchange. In this study, we investigate the impact of soil water availability on Kleaf of Fraxinus ornus L. as well as the influence of Kleaf on gas exchange rates and plant water status. With this aim, Kleaf, leaf conductance to water vapour (gL), leaf water potential (Psileaf) and leaf mass per area (LMA) were measured in F. ornus trees, growing in 21 different sites with contrasting water availability. Plants growing in arid sites had lower Kleaf, gL and Psileaf than those growing in sites with higher water availability. On the contrary, LMA was similar in the two groups. The Kleaf values recorded in sites with two different levels of soil water availability were constantly different from each other regardless of the amount of precipitation recorded over 20 days before measurements. Moreover, Kleaf was correlated with gL values. Our data suggest that down-regulation of Kleaf is a component of adaptation of plants to drought-prone habitats. Low Kleaf implies reduced gas exchange which may, in turn, influence the climatic conditions on a local/regional scale. It is concluded that leaf hydraulics and its changes in response to resource availability should receive greater attention in studies aimed at modelling biosphere-atmosphere interactions.
Quantifying Impacts of Food Trade on Water Availability Considering Water Sources
NASA Astrophysics Data System (ADS)
Oki, T.; Yano, S.; Hanasaki, N.
2012-12-01
Food production requires a lot of water, and traded food potentially has external impacts on environment through reducing the water availability in the producing region. Water footprint is supposed to be an indicator to reflect the impacts of water use. However, impacts of water use on environment, resource, and sustainability are different in place and time, and according to the sources of water withdrawals. Therefore it is preferable to characterize the water withdrawals or consumptions rather than just accumulate the total amount of water use when estimating water footprint. In this study, a new methodology, global green-water equivalent method, is proposed in which regional characterization factors are determined based on the estimates of natural hydrological cycles, such as precipitation, total runoff, and sub-surface runoff, and applied for green-water, river(+reservoir) water, and non-renewable ground water uses. Water footprint of the world associated with the production of 19 major crops was estimated using an integrated hydrological and water resources modeling system (H08), with atmospheric forcing data for 1991-2000 with spatial resolution of 0.5 by 0.5 longitudinal and latitudinal degrees. The impacts is estimated to be 6 times larger than the simple summation of green and blue water uses, and reflect the climatological water scarcity conditions geographically. The results can be used to compare the possible impacts of food trade associated with various crops from various regions on environment through reducing the availability of water resources in the cropping area.
NASA Astrophysics Data System (ADS)
Richey, A. S.; Richey, J. E.; Tan, A.; Liu, M.; Adam, J. C.; Sokolov, V.
2015-12-01
Central Asia presents a perfect case study to understand the dynamic, and often conflicting, linkages between food, energy, and water in natural systems. The destruction of the Aral Sea is a well-known environmental disaster, largely driven by increased irrigation demand on the rivers that feed the endorheic sea. Continued reliance on these rivers, the Amu Darya and Syr Darya, often place available water resources at odds between hydropower demands upstream and irrigation requirements downstream. A combination of tools is required to understand these linkages and how they may change in the future as a function of climate change and population growth. In addition, the region is geopolitically complex as the former Soviet basin states develop management strategies to sustainably manage shared resources. This complexity increases the importance of relying upon publically available information sources and tools. Preliminary work has shown potential for the Variable Infiltration Capacity (VIC) model to recreate the natural water balance in the Amu Darya and Syr Darya basins by comparing results to total terrestrial water storage changes observed from NASA's Gravity Recovery and Climate Experiment (GRACE) satellite mission. Modeled streamflow is well correlated to observed streamflow at upstream gauges prior to the large-scale expansion of irrigation and hydropower. However, current modeled results are unable to capture the human influence of water use on downstream flow. This study examines the utility of a crop simulation model, CropSyst, to represent irrigation demand and GRACE to improve modeled streamflow estimates in the Amu Darya and Syr Darya basins. Specifically we determine crop water demand with CropSyst utilizing available data on irrigation schemes and cropping patterns. We determine how this demand can be met either by surface water, modeled by VIC with a reservoir operation scheme, and/or by groundwater derived from GRACE. Finally, we assess how the inclusion of CropSyst and groundwater to model and meet irrigation demand improves modeled streamflow from VIC throughout the basins. The results of this work are integrated into a decision support platform to assist the basin states in understanding water availability and the impact of management decisions on available resources.
Shields, Katherine F.; Chan, Terence U.; Christenson, Elizabeth; Cronk, Ryan D.; Leker, Hannah; Samani, Destina; Apoya, Patrick; Lutz, Alexandra
2015-01-01
Abstract Safe drinking water is critical to human health and development. In rural sub‐Saharan Africa, most improved water sources are boreholes with handpumps; studies suggest that up to one third of these handpumps are nonfunctional at any given time. This work presents findings from a secondary analysis of cross‐sectional data from 1509 water sources in 570 communities in the rural Greater Afram Plains (GAP) region of Ghana; one of the largest studies of its kind. 79.4% of enumerated water sources were functional when visited; in multivariable regressions, functionality depended on source age, management, tariff collection, the number of other sources in the community, and the district. A Bayesian network (BN) model developed using the same data set found strong dependencies of functionality on implementer, pump type, management, and the availability of tools, with synergistic effects from management determinants on functionality, increasing the likelihood of a source being functional from a baseline of 72% to more than 97% with optimal management and available tools. We suggest that functionality may be a dynamic equilibrium between regular breakdowns and repairs, with management a key determinant of repair rate. Management variables may interact synergistically in ways better captured by BN analysis than by logistic regressions. These qualitative findings may prove generalizable beyond the study area, and may offer new approaches to understanding and increasing handpump functionality and safe water access. PMID:27667863
NASA Astrophysics Data System (ADS)
Fisher, Michael B.; Shields, Katherine F.; Chan, Terence U.; Christenson, Elizabeth; Cronk, Ryan D.; Leker, Hannah; Samani, Destina; Apoya, Patrick; Lutz, Alexandra; Bartram, Jamie
2015-10-01
Safe drinking water is critical to human health and development. In rural sub-Saharan Africa, most improved water sources are boreholes with handpumps; studies suggest that up to one third of these handpumps are nonfunctional at any given time. This work presents findings from a secondary analysis of cross-sectional data from 1509 water sources in 570 communities in the rural Greater Afram Plains (GAP) region of Ghana; one of the largest studies of its kind. 79.4% of enumerated water sources were functional when visited; in multivariable regressions, functionality depended on source age, management, tariff collection, the number of other sources in the community, and the district. A Bayesian network (BN) model developed using the same data set found strong dependencies of functionality on implementer, pump type, management, and the availability of tools, with synergistic effects from management determinants on functionality, increasing the likelihood of a source being functional from a baseline of 72% to more than 97% with optimal management and available tools. We suggest that functionality may be a dynamic equilibrium between regular breakdowns and repairs, with management a key determinant of repair rate. Management variables may interact synergistically in ways better captured by BN analysis than by logistic regressions. These qualitative findings may prove generalizable beyond the study area, and may offer new approaches to understanding and increasing handpump functionality and safe water access. This article was corrected on 11 Nov 2015. See the end of the full text for details.
Public participation in water resources management: Restructuring model of upstream Musi watershed
NASA Astrophysics Data System (ADS)
Andriani, Yuli; Zagloel, T. Yuri M.; Koestoer, R. H.; Suparmoko, M.
2017-11-01
Water is the source of life needed by living things. Human as one of living most in needs of water. Because the population growth follows the geometrical progression, while the natural resource increases calculates the arithmetic. Humans besides needing water also need land for shelter and for their livelihood needs, such as gardening or rice farmers. If the water absorption area is reduced, water availability will decrease. Therefore it is necessary to conduct an in-depth study of water resources management involving the community. The purpose of this study is to analyze community participation in water resources management, so that its availability can still meet the needs of living and sustainable. The method that used the level of community participation according to Arstein theory. The results obtained that community participation is at the level of partnership and power delegation. This level of participation is at the level of participation that determines the sustainability of water resources for present and future generations.
Granular Activated Carbon Performance Capability and Availability.
1983-06-01
services were surveyed to determine availability of data and to develop a strategy for later computerized searches: * Chemical Abstracts; * Engineering ...Chemical Abstracts; * Engineering Abstracts; * Environmental Abstracts; * Selected Water Resources Abstracts; * Pollution Abstracts; and * the U.S...chemicals addressed, and scientific and engineering methods used. Publications were also reviewed for quality and consistency with the bulk of available data
Steinemann, Anne C.
1989-01-01
Powerplant siting is dependent upon many factors; in southern California the prevailing physical constraint is water availability. Increasing land-use and other environmental concerns preclude further sites along the coast. A review of available hydrologic data was made of 142 ground-water basins in the southeast California desert area to ascertain if any could be feasible sources of nonpotable powerplant cooling water. Feasibility implies the capacity to sustain a typical 1,000-megawatt electrical-power generating plant for 30 years with an ample supply of ground water for cooling. Of the 142 basins reviewed, 5 met or exceeded established hydrologic criteria for supplying the water demands of a typical powerplant. These basins are: (1) middle Amargosa valley, (2) Soda Lake valley, (3) Caves Canyon valley, (4) Chuckwalla Valley, and (5) Calzona-Vidal Valley. Geohydrologic evaluations of these five basins assessed the occurrence and suitability of ground water and effects of long-term pumping. An additional six basins met or exceeded hydrologic criteria, with qualifications, for providing powerplant cooling water. The remaining 131 basins either did not meet the criteria, or available data were insufficient to determine if the basins would meet the criteria.
Enhancing vector shoreline data using a data fusion approach
NASA Astrophysics Data System (ADS)
Carlotto, Mark; Nebrich, Mark; DeMichele, David
2017-05-01
Vector shoreline (VSL) data is potentially useful in ATR systems that distinguish between objects on land or water. Unfortunately available data such as the NOAA 1:250,000 World Vector Shoreline and NGA Prototype Global Shoreline data cannot be used by themselves to make a land/water determination because of the manner in which the data are compiled. We describe a data fusion approach for creating labeled VSL data using test points from Global 30 Arc-Second Elevation (GTOPO30) data to determine the direction of vector segments; i.e., whether they are in clockwise or counterclockwise order. We show consistently labeled VSL data be used to easily determine whether a point is on land or water using a vector cross product test.
NASA Astrophysics Data System (ADS)
De Lorenzi, Francesca; Bonfante, Antonello; Alfieri, Silvia Maria; Monaco, Eugenia; De Mascellis, Roberto; Manna, Piero; Menenti, Massimo
2014-05-01
Soil water availability is one of the main components of the terroir concept, influencing crop yield and fruit composition in grapes. The aim of this work is to analyze some elements of the "natural environment" of terroir (climate and soil) in combination with the intra-specific biodiversity of yield responses of grapevine to water availability. From a reference (1961-90) to a future (2021-50) climate case, the effects of climate evolution on soil water availability are assessed and, regarding soil water regime as a predictor variable, the potential spatial distribution of wine-producing cultivars is determined. In a region of Southern Italy (Valle Telesina, 20,000 ha), where a terroir classification has been produced (Bonfante et al., 2011), we applied an agro-hydrological model to determine water availability indicators. Simulations were performed in 60 soil typological units, over the entire study area, and water availability (= hydrological) indicators were determined. Two climate cases were considered: reference (1961-90) and future (2021-2050), the former from climatic statistics on observed variables, and the latter from statistical downscaling of predictions by general circulation models (AOGCM) under A1B SRES scenario. Climatic data consist of daily time series of maximum and minimum temperature, and daily rainfall on a grid with a spatial resolution of 35 km. Spatial and temporal variability of hydrological indicators was addressed. With respect to temporal variability, both inter-annual and intra-annual (i.e. at different stages of crop cycle) variability were analyzed. Some cultivar-specific relations between hydrological indicators and characteristics of must quality were established. Moreover, for several wine-producing cultivars, hydrological requirements were determined by means of yield response functions to soil water availability, through the re-analysis of experimental data derived from scientific literature. The standard errors of estimated requirements were determined. To assess cultivars adaptability, hydrological requirements were evaluated against hydrological indicators. A probabilistic assessment of adaptability was performed, and the inaccuracy of estimated hydrological requirements was accounted for by the error of estimate and its distribution. Maps of cultivars potential distribution, i.e. locations where each cultivar is expected to be compatible with climate, were derived and possible options for adaptation to climate change were defined. The 2021 - 2050 climate scenario was characterized by higher temperatures throughout the year and by a significant decrease in precipitation during spring and autumn. The results have shown the relevant variability of soils water regime and its effects on cultivars adaptability. In the future climate scenario, a hydrological indicator (i.e. relative evapotranspiration deficit - RETD), averaged over the growing season, showed an average increase of 5-8 %, and more pronounced increases occurred in the phenological phases of berry formation and ripening. At the locations where soil hydrological conditions were favourable (like the ancient terraces), hydrological indicators were quite similar in both climate scenarios and the adaptability of the cultivars was high both in the reference and future climate case. The work was carried out within the Italian national project AGROSCENARI funded by the Ministry for Agricultural, Food and Forest Policies (MIPAAF, D.M. 8608/7303/2008) Keywords: climate change, Vitis vinifera L., simulation model, yield response functions, potential cultivation area.
NASA Astrophysics Data System (ADS)
Arsyad, Muhammad; Ihsan, Nasrul; Tiwow, Vistarani Arini
2016-02-01
Maros karst region, covering an area of 43.750 hectares, has water resources that determine the life around it. Water resources in Maros karst are in the rock layers or river underground in the cave. The data used in this study are primary and secondary data. Primary data includes characteristics of the medium. Secondary data is rainfall data from BMKG, water discharge data from the PSDA, South Sulawesi province in 1990-2010, and the other characteristics data Maros karst, namely cave, flora and fauna of the Bantimurung Bulusaraung National Park. Data analysis was conducted using laboratory test for medium characteristics Maros karst, rainfall and water discharge were analyzed using Minitab Program 1.5 to determine their profile. The average rainfall above 200 mm per year occurs in the range of 1999 to 2005. The availability of the water discharge at over 50 m3/s was happened in 1993 and 1995. Prediction was done by modeling Autoregressive Integrated Moving Average (ARIMA), with the rainfall data shows that the average precipitation for four years (2011-2014) will sharply fluctuate. The prediction of water discharge in Maros karst region was done for the period from January to August in 2011, including the type of 0. In 2012, the addition of the water discharge started up in early 2014.
McCluney, Kevin E.; Belnap, Jayne; Collins, Scott L.; González, Angélica L.; Hagen, Elizabeth M.; Holland, J. Nathaniel; Kotler, Burt P.; Maestre, Fernando T.; Smith, Stanley D.; Wolf, Blair O.
2012-01-01
Species interactions play key roles in linking the responses of populations, communities, and ecosystems to environmental change. For instance, species interactions are an important determinant of the complexity of changes in trophic biomass with variation in resources. Water resources are a major driver of terrestrial ecology and climate change is expected to greatly alter the distribution of this critical resource. While previous studies have documented strong effects of global environmental change on species interactions in general, responses can vary from region to region. Dryland ecosystems occupy more than one-third of the Earth's land mass, are greatly affected by changes in water availability, and are predicted to be hotspots of climate change. Thus, it is imperative to understand the effects of environmental change on these globally significant ecosystems. Here, we review studies of the responses of population-level plant-plant, plant-herbivore, and predator-prey interactions to changes in water availability in dryland environments in order to develop new hypotheses and predictions to guide future research. To help explain patterns of interaction outcomes, we developed a conceptual model that views interaction outcomes as shifting between (1) competition and facilitation (plant-plant), (2) herbivory, neutralism, or mutualism (plant-herbivore), or (3) neutralism and predation (predator-prey), as water availability crosses physiological, behavioural, or population-density thresholds. We link our conceptual model to hypothetical scenarios of current and future water availability to make testable predictions about the influence of changes in water availability on species interactions. We also examine potential implications of our conceptual model for the relative importance of top-down effects and the linearity of patterns of change in trophic biomass with changes in water availability. Finally, we highlight key research needs and some possible broader impacts of our findings. Overall, we hope to stimulate and guide future research that links changes in water availability to patterns of species interactions and the dynamics of populations and communities in dryland ecosystems.
Reality check of socio-hydrological interactions in water quality and ecosystem management
NASA Astrophysics Data System (ADS)
Destouni, Georgia; Fischer, Ida; Prieto, Carmen
2017-04-01
Socio-hydrological interactions in water management for improving water quality and ecosystem status include as key components both (i) the societal measures taken for mitigation and control, and (ii) the societal characterization and monitoring efforts made for choosing management targets and checking the effects of measures taken to reach the targets. This study investigates such monitoring, characterization and management efforts and effects over the first six-year management cycle of the EU Water Framework Directive (WFD). The investigation uses Sweden and the WFD-regulated management of its stream and lake waters as a concrete quantification example, with focus on the nutrient and eutrophication conditions that determine the most prominent water quality and ecosystem problems in need of mitigation in the Swedish waters. The case results show a relatively small available monitoring base for determination of these nutrient and eutrophication conditions, even though they constitute key parts in the overall WFD-based approach to classification and management of ecosystem status. Specifically, actual nutrient monitoring exists in only around 1% (down to 0.2% for nutrient loads) of the Swedish stream and lake water bodies; modeling is used to fill the gaps for the remaining unmonitored fraction of classified and managed waters. The available data show that the hydro-climatically driven stream water discharge is a primary explanatory variable for the resulting societal classification of ecosystem status in Swedish waters; this may be due to the discharge magnitude being dominant in determining nutrient loading to these waters. At any rate, with such a hydro-climatically related, rather than human-pressure related, determinant of the societal ecosystem-status classification, the main human-driven causes and effects of eutrophication may not be appropriately identified, and the measures taken for mitigating these may not be well chosen. The available monitoring data from Swedish waters support this hypothesis, by showing that the first WFD management cycle 2009-2015 has led to only slight changes in measured nutrient concentrations, with moderate-to-bad status waters mostly undergoing concentration increases. These management results are in direct contrast to the WFD management goals that ecosystem status in all member-state waters must be improved to at least good level, and in any case not be allowed to further deteriorate. In general, the present results show that societal approaches to ecosystem status classification, monitoring and improvement may need a focus shift for improved identification and quantification of the human-driven components of nutrient inputs, concentrations and loads in water environments. Dominant hydro-climatic change drivers and effects must of course also be understood and accounted for. However, adaptation to hydro-climatic changes should be additional to and aligned with, rather than instead of, necessary mitigation of human-driven eutrophication. The present case results call for further science-based testing and evidence of societal water quality and ecosystem management actually targeting and following up the potential achievement of such mitigation.
Water availability as dominant control of heat stress responses in two contrasting tree species.
Ruehr, Nadine K; Gast, Andreas; Weber, Christina; Daub, Baerbel; Arneth, Almut
2016-02-01
Heat waves that trigger severe droughts are predicted to increase globally; however, we lack an understanding of how trees respond to the combined change of extreme temperatures and water availability. Here, we studied the impacts of two consecutive heat waves as well as post-stress recovery in young Pseudotsuga menziesii (Mirb.) Franco (Douglas-fir) and Robinia pseudoacacia L. (black locust) growing under controlled conditions. Responses were compared under water supply close to the long-term average and under reduced irrigation to represent drought. Exposure to high temperatures (+10 °C above ambient) and vapour pressure deficit strongly affected the trees in terms of water relations, photosynthesis and growth. Douglas-fir used water resources conservatively, and transpiration decreased in response to mild soil water limitation. In black locust, heat stress led to pronounced tree water deficits (stem diameter shrinkage), accompanied by leaf shedding to alleviate stress on the hydraulic system. The importance of water availability during the heat waves became further apparent by a concurrent decline in photosynthesis and stomatal conductance with increasing leaf temperatures in both species, reaching the lowest rates in the heat-drought treatments. Stress severity determined both the speed and the amount of recovery. Upon release of stress, photosynthesis recovered rapidly in drought-treated black locust, while it remained below control rates in heat (t = -2.4, P < 0.05) and heat-drought stressed trees (t = 2.96, P < 0.05). In Douglas-fir, photosynthesis recovered quickly, while water-use efficiency increased in heat-drought trees because stomatal conductance remained reduced (t = -2.92, P < 0.05). Moreover, Douglas-fir was able to compensate for stem-growth reductions following heat (-40%) and heat-drought stress (-68%), but most likely at the expense of storage and other growth processes. Our results highlight the importance of studying heat waves alongside changes in water availability. They further suggest that we should look beyond the actual stress event to identify lagged effects and acclimation processes that may determine tree resilience in the long term. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Applications of remote sensing to water resources
NASA Technical Reports Server (NTRS)
1977-01-01
Analyses were made of selected long-term (1985 and beyond) objectives, with the intent of determining if significant data-related problems would be encountered and to develop alternative solutions to any potential problems. One long-term objective selected for analysis was Water Availability Forecasting. A brief overview was scheduled in FY-77 of the objective -- primarily a fact-finding study to allow Data Management personnel to gain adequate background information to perform subsequent data system analyses. This report, includes discussions on some of the larger problems currently encountered in water measurement, the potential users of water availability forecasts, projected demands of users, current sensing accuracies, required parameter monitoring, status of forecasting modeling, and some measurement accuracies likely to be achievable by 1980 and 1990.
NASA Astrophysics Data System (ADS)
Liu, Dedi; Guo, Shenglian; Shao, Quanxi; Liu, Pan; Xiong, Lihua; Wang, Le; Hong, Xingjun; Xu, Yao; Wang, Zhaoli
2018-01-01
Human activities and climate change have altered the spatial and temporal distribution of water availability which is a principal prerequisite for allocation of different water resources. In order to quantify the impacts of climate change and human activities on water availability and optimal allocation of water resources, hydrological models and optimal water resource allocation models should be integrated. Given that increasing human water demand and varying water availability conditions necessitate adaptation measures, we propose a framework to assess the effects of these measures on optimal allocation of water resources. The proposed model and framework were applied to a case study of the middle and lower reaches of the Hanjiang River Basin in China. Two representative concentration pathway (RCP) scenarios (RCP2.6 and RCP4.5) were employed to project future climate, and the Variable Infiltration Capacity (VIC) hydrological model was used to simulate the variability of flows under historical (1956-2011) and future (2012-2099) conditions. The water availability determined by simulating flow with the VIC hydrological model was used to establish the optimal water resources allocation model. The allocation results were derived under an extremely dry year (with an annual average water flow frequency of 95%), a very dry year (with an annual average water flow frequency of 90%), a dry year (with an annual average water flow frequency of 75%), and a normal year (with an annual average water flow frequency of 50%) during historical and future periods. The results show that the total available water resources in the study area and the inflow of the Danjiangkou Reservoir will increase in the future. However, the uneven distribution of water availability will cause water shortage problems, especially in the boundary areas. The effects of adaptation measures, including water saving, and dynamic control of flood limiting water levels (FLWLs) for reservoir operation, were assessed and implemented to alleviate water shortages. The negative impacts from the South-to-North Water Transfer Project (Middle Route) in the mid-lower reaches of the Hanjiang River Basin can be avoided through the dynamic control of FLWLs in Danjiangkou Reservoir, under the historical and future RCP2.6 and RCP4.5 scenarios. However, the effects of adaptation measures are limited due to their own constraints, such as the characteristics of the reservoirs influencing the FLWLs. The utilization of storm water appears necessary to meet future water demand. Overall, the results indicate that the framework for assessing the effects of adaptation measures on water resources allocation might aid water resources management, not only in the study area but also in other places where water availability conditions vary due to climate change and human activities.
NASA Technical Reports Server (NTRS)
Dunaway, Brian; Edeen, Marybeth
2000-01-01
Water to be generated by, delivered to, and processed by the International Space Station (ISS) is a critical Environmental Control and Life Support (ECLS) element, especially for the early ISS missions. A significant portion of the water required by the ISS shall be provided by the Shuttle Transportation System (STS) Orbiter. The balance of water generated by the Orbiter Fuel Cells (FC), minus that water consumed by the Orbiter Flash Evaporator System (FES) and crew, is available for transfer to the ISS. During later missions, crew respired and perspired water, as well as effluent water from the Orbiter LiOH canisters, will be collected as condensate and available for transfer to the ISS. Orbiter radiator performance provides the most variance in determining the amount of net Orbiter water available for transfer to the ISS. As radiator performance decreases, the dependence upon the FES (and FC water) increases for rejecting Orbiter waste heat. Generally, radiator performance decreases as the ISS assembly size increases (especially as solar arrays are added), and also as beta angle increases. ISS solar array deployment necessitates the use of models with articulating solar arrays (for Earth local-vertical attitudes), as array position dramatically affects Orbiter radiator performance. Recent developments in the relaxation of beta angle limitations have also increased the complexity and difficulty of providing water to the ISS. Other factors that may hinder the ability to transfer water are the number of empty Contingency Water Containers (CWCs) available, duration of open-hatch time, crew activity timeline, and full CWC storage capability. A parametric study has been accomplished that provides a quick-reference table for determining expected water generation rates for ISS missions 2A.2 through 7A.1. An hourly Orbiter water generation rate is reported according to a matrix that consists of: (1) (six) significant changes in ISS assembly configuration; (2) (four) beta angles (0 deg. , +37 deg., +53 deg. , and +75 deg.); (3) the (three) most representative ISS attitudes (XPOP-O, XPOP-180 and +XVV); (4) (four) Orbiter radiator configurations (both stowed, starboard deployed, port deployed, and both deployed) and (5) the (two) conditions (radiator inlet temperatures and fuel cell power) most consistent with sleep and wake periods. Those permutations of higher probability of occurrence than others have been identified. Another parametric study has been accomplished that provides a quick-reference table for determining expected water generation rates for ISS assembly complete missions. An hourly Orbiter water generation rate is reported according to a matrix that consists of: (1) (seven) beta angles (-75 deg., -60 deg., -30 deg., 0 deg., +30 deg., +60 deg., and +75 deg.); (2) the (nine) PYR angles that define the corners of the envelope; (3) (four) Orbiter radiator configurations (both stowed, starboard deployed, port deployed, and both deployed) and (4) the (two) conditions (radiator inlet temperatures and fuel cell power) most consistent with sleep and wake periods.
Spectrophotometric method for the determination of paraquat in water, grain and plant materials.
Shivhare, P; Gupta, V K
1991-04-01
A sensitive spectrophotometric method for the determination of paraquat using ascorbic acid (an easily available reducing agent) is described. Paraquat is reduced with ascorbic acid in alkaline solution to give a blue radical ion with an absorbance maximum at 600 nm. Beer's law is obeyed in the range 12-96 micrograms of paraquat in 10 ml of the final solution (1.2-9.6 ppm). The important analytical parameters and the optimum reaction conditions were evaluated. The method was applied successfully to the determination of paraquat in water, grain and plant materials.
Water from the Coastal Plain aquifers in the Washington, D.C., metropolitan area
Papadopulos, S.S.; Bennett, R.R.; Mack, F.K.; Trescott, P.C.
1974-01-01
A brief study of the Atlantic Coastal Plain aquifers in the vicinity of the Washington, D.C., metropolitan area was made, using available data, to estimate the water-supply potential of these aquifers and to determine the possibility of developing an emergency water supply during droughts. Assuming that the data available are representative, the study indicates that the water-supply potential of these aquifers, within an assumed 30-mile radius of Washington, D.C., is about 170 million gallons per day. That is, these aquifers, which are now furnishing an estimated 60 million gallons per day, could be developed to supply an additional 110 million gallons per day on a continuous basis. This quantity might be even larger if a significant amount of water is derived from leakage through finer grained confining beds, but further studies would be necessary to determine the amount of leakage and the long-term effects of large-scale continuous use. Furthermore, under intermittent pumping conditions, an assumed emergency supply of 100 million gallons per day could probably be developed from well fields within a 30-mile radius of Washington. An exploration and testing program would be necessary to assess the reliability of these preliminary estimates.
Ground-water areas and well logs, central Sevier Valley, Utah
Young, Richard A.
1960-01-01
Between September 1959 and June 1960 the United States Geological Survey and the Utah State Engineer, with financial assistance from Garfield, Millard, Piute, Sanpete, and Sevier Counties and from local water-users’ associations, cooperated in an investigation to determine the structural framework of the central Sevier Valley and to evaluate the valley’s ground-water potential. An important aspect of the study was the drilling of 22 test holes under private contract. These data and other data collected during the course of the larger ground-water investigation of which the test drilling was a part will be evaluated in a report on the geology and ground-water resources of the central Sevier Valley. The present report has been prepared to make available the logs of test holes and to describe in general terms the availability of ground water in the different areas of the valley.
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.
Oki, Delwyn S.
2002-01-01
An estimate of ground-water availability in the Hawi area of north Kohala, Hawaii, is needed to determine whether ground-water resources are adequate to meet future demand within the area and other areas to the south. For the Hawi area, estimated average annual recharge from infiltration of rainfall, fog drip, and irrigation is 37.5 million gallons per day from a daily water budget. Low and high annual recharge estimates for the Hawi area that incorporate estimated uncertainty are 19.9 and 55.4 million gallons per day, respectively. The recharge estimates from this study are lower than the recharge of 68.4 million gallons per day previously estimated from a monthly water budget. Three ground-water models, using the low, intermediate, and high recharge estimates (19.9, 37.5, and 55.4 million gallons per day, respectively), were developed for the Hawi area to simulate ground-water levels and discharges for the 1990?s. To assess potential ground-water availability, the numerical ground-water flow models were used to simulate the response of the freshwater-lens system to withdrawals at rates in excess of the average 1990?s withdrawal rates. Because of uncertainty in the recharge estimate, estimates of ground-water availability also are uncertain. Results from numerical simulations indicate that for appropriate well sites, depths, and withdrawal rates (1) for the low recharge estimate (19.9 million gallons per day) it may be possible to develop an additional 10 million gallons per day of fresh ground water from the Hawi area and maintain a freshwater-lens thickness of 160 feet near the withdrawal sites, (2) for the intermediate recharge estimate (37.5 million gallons per day) it may be possible to develop an additional 15 million gallons per day of fresh ground water from the Hawi area and maintain a freshwater-lens thickness of 190 feet near the withdrawal sites, and (3) for the high recharge estimate (55.4 million gallons per day) it may be possible to develop at least an additional 20 million gallons per day of fresh ground water from the Hawi area and maintain a freshwater-lens thickness of 200 feet near the withdrawal sites. Other well-field configurations than the ones considered potentially could be used to develop more fresh ground water than indicated by the scenarios tested in this study. Depth, spacing, and withdrawal rates of individual wells are important considerations in determining ground-water availability. The regional models developed for this study cannot predict whether local saltwater intrusion problems may occur at individual withdrawal sites. Results of this study underscore the importance of collecting new information to better constrain the recharge estimates.
Horn, M.A.
2000-01-01
Techniques for management of drainage basins that use water budgets to balance available water resources with actual or anticipated water use require accurate and precise estimates of basin withdrawals, interbasin transfers of freshwater, unaccounted-for use, water use, consumptive use, inflow and infiltration, basin return flow, and interbasin transfers of wastewater. Frequently, interbasin transfers of freshwater and wastewater are not included in basin water budgets because they occur within public water-delivery and wastewater-collection systems. A new 10-step method was developed to improve estimates of inflow and infiltration and interbasin transfers using readily available statewide data. The accuracy and precision of water-use estimates determined by this method are improved through careful application of coefficients for small users and the use of metered values for large users. The method was developed and tested with data for the Ten Mile River Basin in southeastern Massachusetts. This report uses examples from the basin to illustrate each step of the method.
Industrial water supplies of the United States
Love, Samuel K.
1954-01-01
The availability of adequate supplies of water of suitable quality determines in large measure the potential for industrial development in any community. However, the pattern of availability of water for industrial use is not so generally recognized. It is the purpose of this paper to point out the more important factors affecting the distribution and quality of existing and potential sources of water with particular reference to industrial development. From a nation-wide standpoint our country is blessed with plenty of water. If the available water could be distributed completely in accordance with needs, it is probable that no part of the country would suffer from lack of water either now or in the foreseeable future. As nature has not dealt so providently however, or perhaps as man has not been able to cope with the vagaries of nature, we find ourselves beset with droughts and floods. Added to the natural deficiencies of nature are man-made difficulties such as lowered ground-water tables and salt-water encroachment of fresh water supplies resulting from overpumping of ground waters, pollution in all its forms, and wasteful use of water for many purposes. It becomes necessary, therefore, to study and evaluate our most important natural resource in order that we may use it more intelligently. This is particularly true in regard to continued industrial growth of our country.
Brown, Juliane B.
2008-01-01
Historical water-quality data in the National Park Service Southern Colorado Plateau Network have been collected irregularly and with little followup interpretation, restricting the value of the data. To help address these issues, to inform future water-quality monitoring planning efforts, and to address relevant National Park Service Inventory and Monitoring Program objectives, the U.S. Geological Survey, in cooperation with the National Park Service, compiled, reviewed, and summarized available historical water-quality data for 19 park units in the Southern Colorado Plateau Network. The data are described in terms of availability by major water-quality classes, park unit, site type, and selected identified water sources. The report also describes the geology, water resources, water-quality issues, data gaps, and water-quality standard exceedances identified in five of the park units determined to be of high priority. The five park units are Bandelier National Monument in New Mexico, Canyon de Chelly National Monument in Arizona, Chaco Culture National Historical Park in New Mexico, Glen Canyon National Recreation Area in Arizona and Utah, and Mesa Verde National Park in Colorado. Statistical summaries of water-quality characteristics are presented and considerations for future water-quality monitoring are provided for these five park units.
Topographic, edaphic, and vegetative controls on plant-available water
Salli F. Dymond; John B. Bradford; Paul V. Bolstad; Randall K. Kolka; Stephen D. Sebestyen; Thomas M. DeSutter
2017-01-01
Soil moisture varies within landscapes in response to vegetative, physiographic, and climatic drivers, which makes quantifying soil moisture over time and space difficult. Nevertheless, understanding soil moisture dynamics for different ecosystems is critical, as the amount of water in a soil determines a myriad ecosystem services and processes such as net primary...
Determination of Iron in Water. Training Module 5.210.2.77.
ERIC Educational Resources Information Center
Bonte, John L.; Davidson, Arnold C.
This document is an instructional module package prepared in objective form for use by an instructor familiar with the spectrophotometric analysis of total iron, filtrable iron and ferrous iron in a water supply. Included are objectives, an instructor guide, student handouts, and transparency masters. A video tape is also available from the…
Code of Federal Regulations, 2012 CFR
2012-04-01
... Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER IRRIGATION OPERATION AND...) Annual operation and maintenance assessment rates may be lowered through the exercise of our discretion... supplemental water is available, the calculation of your annual operation and maintenance assessment rate may...
Code of Federal Regulations, 2013 CFR
2013-04-01
... Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER IRRIGATION OPERATION AND...) Annual operation and maintenance assessment rates may be lowered through the exercise of our discretion... supplemental water is available, the calculation of your annual operation and maintenance assessment rate may...
Code of Federal Regulations, 2014 CFR
2014-04-01
... Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER IRRIGATION OPERATION AND...) Annual operation and maintenance assessment rates may be lowered through the exercise of our discretion... supplemental water is available, the calculation of your annual operation and maintenance assessment rate may...
Point-of-use chlorination of turbid water: results from a field study in Tanzania.
Mohamed, Hussein; Brown, Joe; Njee, Robert M; Clasen, Thomas; Malebo, Hamisi M; Mbuligwe, Steven
2015-06-01
Household-based chlorine disinfection is widely effective against waterborne bacteria and viruses, and may be among the most inexpensive and accessible options for household water treatment. The microbiological effectiveness of chlorine is limited, however, by turbidity. In Tanzania, there are no guidelines on water chlorination at household level, and limited data on whether dosing guidelines for higher turbidity waters are sufficient to produce potable water. This study was designed to assess the effectiveness of chlorination across a range of turbidities found in rural water sources, following local dosing guidelines that recommend a 'double dose' for water that is visibly turbid. We chlorinated water from 43 sources representing a range of turbidities using two locally available chlorine-based disinfectants: WaterGuard and Aquatabs. We determined free available chlorine at 30 min and 24 h contact time. Our data suggest that water chlorination with WaterGuard or Aquatabs can be effective using both single and double doses up to 20 nephelometric turbidity units (NTU), or using a double dose of Aquatabs up to 100 NTU, but neither was effective at turbidities greater than 100 NTU.
NASA Astrophysics Data System (ADS)
Russo, T. A.; Devineni, N.; Lall, U.
2015-12-01
Lasting success of the Green Revolution in Punjab, India relies on continued availability of local water resources. Supplying primarily rice and wheat for the rest of India, Punjab supports crop irrigation with a canal system and groundwater, which is vastly over-exploited. The detailed data required to physically model future impacts on water supplies agricultural production is not readily available for this region, therefore we use Bayesian methods to estimate hydrologic properties and irrigation requirements for an under-constrained mass balance model. Using measured values of historical precipitation, total canal water delivery, crop yield, and water table elevation, we present a method using a Markov chain Monte Carlo (MCMC) algorithm to solve for a distribution of values for each unknown parameter in a conceptual mass balance model. Due to heterogeneity across the state, and the resolution of input data, we estimate model parameters at the district-scale using spatial pooling. The resulting model is used to predict the impact of precipitation change scenarios on groundwater availability under multiple cropping options. Predicted groundwater declines vary across the state, suggesting that crop selection and water management strategies should be determined at a local scale. This computational method can be applied in data-scarce regions across the world, where water resource management is required to resolve competition between food security and available resources in a changing climate.
On the Concept of Hydrologic Space
NASA Astrophysics Data System (ADS)
Ellison, D.
2017-12-01
Forests provide a number of important water-related ecosystem services including water purification and flood mitigation. We illustrate that the forest role in precipitation recycling and the regulation of the hydrologic cycle must also be clearly recognized as an ecosystem service. Deforestation leads to more local runoff and reduced precipitation. However, the importance of afforestation in contributing to the flow of atmospheric moisture and thus promoting precipitation recycling is underappreciated. Since much of the evapotranspiration from forests falls again as precipitation, the terrestrial, forest-based production of atmospheric moisture has important consequences, both for local and downwind precipitation and water availability. We emphasize the importance of inter-basin connectivity: what happens in one basin cannot be separated from what happens in others. This spatial interconnectedness is poorly reflected in the study of land-atmosphere interactions and the contribution of forests to the hydrologic regime. Focusing on the supply-side characteristics of rainfall, we define and develop the concept of hydrologic space and apply the concept to the derivation of the catchment basin water balance. Conventional approaches to the c-basin water balance typically fail to consider the import and export of atmospheric moisture as a principal determinant of locally and regionally available water supply. Land use modification has important implications for the availability of atmospheric moisture, the production of precipitation, the re-export of available moisture and the availability of runoff: the total amount of water available for productive and consumptive purposes. These consequences are not adequately recognized in most policy efforts at multiple scales and levels of governance.
Estimated water use and availability in the East Narragansett Bay study area, Rhode Island, 1995-99
Wild, Emily C.
2007-01-01
Water availability became a concern in Rhode Island during a drought in 1999, and further investigation was needed to assess the current demands on the hydrologic system from withdrawals during periods of little to no precipitation. The low ground-water levels and streamflows measured in Rhode Island prompted initiation of a series of studies on water use and availability in each major drainage area in Rhode Island for the period 1995–99. The investigation of the East Narragansett Bay area is the last of these studies. The East Narragansett Bay study area (130.9 square miles) includes small sections of the Ten Mile and Westport River Basins in Rhode Island. The area was divided into three regions (islands and contiguous land areas separated by the bay) within each of which the freshwater water use and availability were assessed. During the study period from 1995 through 1999, three major public water suppliers in the study area withdrew 7.601 million gallons per day (Mgal/d) from ground-water and surface-water reservoirs. The estimated water withdrawals by minor public water suppliers during the study period were 0.063 Mgal/d. Total self-supply domestic, industrial, commercial, and agricultural withdrawals from the study area averaged 1.891 Mgal/d. Total water use in the study area averaged 16.48 Mgal/d, of which about 8.750 Mgal/d was imported from other basins. The average return flow to freshwater within the basin was 2.591 Mgal/d, which included effluent from permitted facilities and septic systems. The average return flow to saltwater (Narragansett Bay) outside of the basin was about 45.21 Mgal/d and included discharges by permitted facilities (wastewater-treatment plants and Rhode Island Pollutant Discharge Elimination Systems). The PART program, a computerized hydrographseparation application, was used for the data collected at two selected index stream-gaging stations in the East Narragansett Bay study area to determine water availability on the basis of the 75th, 50th, and 25th percentiles of the total base flow; the base flow for the 7-day, 10-year low-flow scenario; and the base flow for the Aquatic Base Flow scenario for both stations. Base flows in the study area were lowest in September for the 75th, 50th, and 25th percentiles. The safe yields determined for the surface-water reservoirs (14.10 Mgal/d) were added to the estimated available ground water (gross yield) in the Southeastern Narragansett and East Narragansett Islands regions to give the total available water. The water availability in the study area at the 50th percentile ranged from 33.18 Mgal/d in September to 94.62 Mgal/d in June, water availability for the 7-day, 10-year low-flow scenario at the 50th percentile ranged from 21.87 Mgal/d in September to 83.03 Mgal/d in June, and water availability for the Aquatic Base Flow scenario at the 50th percentile ranged from 14.10 Mgal/d in August and September to 65.48 Mgal/d in June. Because water withdrawals and use are greater during the summer than at other times of the year, water availability in June, July, August, and September was compared to water withdrawals in the three regions. For the study period, the withdrawals in July were higher than in the other summer months. For the 50th percentile, the ratios of water withdrawn to water available were close to one in August for the estimated basic and Aquatic Base Flow scenarios and in September for the estimated 7-day, 10-year low-flow scenario. For the 25th percentile, the ratios were close to one in August for the estimated basic and for the 7-day, 10-year low-flow scenario, and were close to one in July for the estimated Aquatic Base Flow scenario. A long-term water budget was calculated for the East Narragansett Bay study area to identify and assess inflows and outflows by region. The water withdrawals and return flows used in the budget were from 1995 through 1999. Total inflow and outflow were calculated separately for each region. Inflow was assumed to equal outflow; the total water budget was 292.1 Mgal/d for the study area. Precipitation and return flow were 99 and less than 1 percent of the total estimated inflow to the study area, respectively. Evapotranspiration, streamflow, and water withdrawals were 47, 49, and 3 percent of the total outflow from the study area, respectively.
Waddell, K.M.; Freethey, G.W.; Susong, D.D.; Pyper, G.E.
1991-01-01
Problem: Questions have been raised concerning the adequacy of available water to fulfill the needs of storage, exchanges, diversions, and instream flows, pursuant to existing water rights in the Provo River drainage basin part of the Bonneville Unit. Also, concern has been expressed about the potential for seepage of water from Jordanelle Reservoir to underground mines. The Utah Congressional Delegation requested that the U.S. Geological Survey (USGS) review the results of analyses performed by and for the USBR.Purpose and Scope: The purpose of this report is to present the results of the USGS review of (1) the hydrologic data, techniques, and model used by the USBR in their hydrologic analyses of the Provo River drainage basin and (2) the results of a study of the potential for seepage from the Jordanelle Reservoir to nearby underground mines.The USGS reviewed USBR-supplied water demands, water utilization studies, and models of seepage from Jordanelle Reservoir. The USBR estimated that about 90 percent of the water supply for Jordanelle Reservoir will be water from Strawberry Reservoir exchanged for water from the Provo River stored in Utah Lake. If the Utah State Engineer allows the USBR to claim an estimated 19,700 acre-feet of return flows from the CUP, only about 77 percent of the supply would be derived from exchange of existing water rights in Utah Lake. The USGS assumed that planned importations of water from the Uinta Basin will be available and deliverable to fulfill the proposed exchanges.Water rights and demands are important for determining water availability. The USGS did not conduct an independent review of water rights and demands. The USSR and Utah Division of Water Rights use different methods in some areas for determining stress on the system based on past records. The USSR used "historical observed diversions" and the Utah Division of Water Rights use "diversion entitlements", which may not be equal to the historical diversions. The USGS based its review upon water demands used by the USSR. The Utah Division of Water Rights has responsibility for granting and enforcing water rights, and the final decisions on how the rights will be adjudicated lies with the Utah Division of Water Rights and with the courts. The USGS review did not consider the draft water distribution plan for the Utah Lake drainage basin proposed by the Utah State Engineer (written commun., October 15,1991). This plan, when finalized, may have an effect on water availability to the CUP.
76 FR 26968 - Proposed Flood Elevation Determinations
Federal Register 2010, 2011, 2012, 2013, 2014
2011-05-10
... County Maps are available for inspection at the Sacramento County Water Resources Department, 827 7th... Creek Approximately 500 feet None +125 Town of Clarks, Village downstream of the of Grayson. railroad... U.S. Route 165, Columbia, LA 71418. Village of Grayson Maps are available for inspection at the...
America's Water in the 20th Century: Measures to address climate induced risk
NASA Astrophysics Data System (ADS)
Devineni, N.
2017-12-01
This work develops an understanding of water risk for USA considering linkages between water supply and competing demands. It explores how climate variability and changing water demands manifest as water deficits and how public-private management decisions determine regional water availability and drought resilience. We develop insights on regional water risks, infrastructure investments, sectoral allocation and policy modifications for America's future water sustainability. In this talk, I will focus on demonstrating how the variations in climate over the last century influenced changes in water use across the continent USA. A peak into our interactive modeling environment for future evolution of water use and supply will also be provided.
Tietjen, Britta; Schlaepfer, Daniel R; Bradford, John B; Lauenroth, William K; Hall, Sonia A; Duniway, Michael C; Hochstrasser, Tamara; Jia, Gensuo; Munson, Seth M; Pyke, David A; Wilson, Scott D
2017-07-01
Drylands occur worldwide and are particularly vulnerable to climate change because dryland ecosystems depend directly on soil water availability that may become increasingly limited as temperatures rise. Climate change will both directly impact soil water availability and change plant biomass, with resulting indirect feedbacks on soil moisture. Thus, the net impact of direct and indirect climate change effects on soil moisture requires better understanding. We used the ecohydrological simulation model SOILWAT at sites from temperate dryland ecosystems around the globe to disentangle the contributions of direct climate change effects and of additional indirect, climate change-induced changes in vegetation on soil water availability. We simulated current and future climate conditions projected by 16 GCMs under RCP 4.5 and RCP 8.5 for the end of the century. We determined shifts in water availability due to climate change alone and due to combined changes of climate and the growth form and biomass of vegetation. Vegetation change will mostly exacerbate low soil water availability in regions already expected to suffer from negative direct impacts of climate change (with the two RCP scenarios giving us qualitatively similar effects). By contrast, in regions that will likely experience increased water availability due to climate change alone, vegetation changes will counteract these increases due to increased water losses by interception. In only a small minority of locations, climate change-induced vegetation changes may lead to a net increase in water availability. These results suggest that changes in vegetation in response to climate change may exacerbate drought conditions and may dampen the effects of increased precipitation, that is, leading to more ecological droughts despite higher precipitation in some regions. Our results underscore the value of considering indirect effects of climate change on vegetation when assessing future soil moisture conditions in water-limited ecosystems. © 2017 John Wiley & Sons Ltd.
Tietjen, Britta; Schlaepfer, Daniel R.; Bradford, John B.; Laurenroth, William K.; Hall, Sonia A.; Duniway, Michael C.; Hochstrasser, Tamara; Jia, Gensuo; Munson, Seth M.; Pyke, David A.; Wilson, Scott D.
2017-01-01
Drylands occur world-wide and are particularly vulnerable to climate change since dryland ecosystems depend directly on soil water availability that may become increasingly limited as temperatures rise. Climate change will both directly impact soil water availability, and also change plant biomass, with resulting indirect feedbacks on soil moisture. Thus, the net impact of direct and indirect climate change effects on soil moisture requires better understanding.We used the ecohydrological simulation model SOILWAT at sites from temperate dryland ecosystems around the globe to disentangle the contributions of direct climate change effects and of additional indirect, climate change-induced changes in vegetation on soil water availability. We simulated current and future climate conditions projected by 16 GCMs under RCP 4.5 and RCP 8.5 for the end of the century. We determined shifts in water availability due to climate change alone and due to combined changes of climate and the growth form and biomass of vegetation.Vegetation change will mostly exacerbate low soil water availability in regions already expected to suffer from negative direct impacts of climate change (with the two RCP scenarios giving us qualitatively similar effects). By contrast, in regions that will likely experience increased water availability due to climate change alone, vegetation changes will counteract these increases due to increased water losses by interception. In only a small minority of locations, climate change induced vegetation changes may lead to a net increase in water availability. These results suggest that changes in vegetation in response to climate change may exacerbate drought conditions and may dampen the effects of increased precipitation, i.e. leading to more ecological droughts despite higher precipitation in some regions. Our results underscore the value of considering indirect effects of climate change on vegetation when assessing future soil moisture conditions in water-limited ecosystems.
Selection of forages by timor deer (cervus timorensis blainville) in menjangan island, bali
NASA Astrophysics Data System (ADS)
Ketut Ginantra, I.; Bagus Made Suaskara, Ida; Ketut Muksin, I.
2018-03-01
This study was conducted to determine the selection of forages plants by Timor deer (Cervus timorensis) on Menjangan Island and its relation to the availability, chemical and physical properties of feed plants. The study was conducted in July-September 2016 in savanna and monsoon forest habitats. The availability of habitat feed plants in the habitat was determined by the quadrat method, and the species of plant eaten by Timor deer was determined through the microhistological analysis of the fecal sample. The food selection index is determine by the Ivlev index. Energy contents of forages plants by bomb calorimeter apparatus, crude protein analyzed by Semi-Micro Kjeldahl technique, NDF, ADF and lignin levels refer to the method of Goering and Van Soest. Mineral content of calcium (Ca) and phosphorus (P) by using atomic absorption spectrophotometer. Determination of tannin content with Folin Denish reaction. Physical properties determine are water regain capacity and water solubility. The relationship between availability with the utilization of plants by Timor deer was analyzed with the similarity index. Multiple regression statistic to test the relationship between index selection with nutritional value factor and physical characteristic of plant species. The result showed that Timor deer selected 32 plants species of graminoids, forbs and woody plants. Feeding selection of Timor deer is strongly influenced by the availability of forage plants in habitat. The feeding selection was significantly influenced by three predictor variables i.e. positive nutritional value is crude protein and negative nutritional value were lignin and tannins. Selection of forage plant Timor deer is positively correlated with the physical properties of feed plants.
Data compilation and assessment for water resources in Pennsylvania state forest and park lands
Galeone, Daniel G.
2011-01-01
As a result of a cooperative study between the U.S. Geological Survey and the Pennsylvania Department of Conservation and Natural Resources (PaDCNR), available electronic data were compiled for Pennsylvania state lands (state forests and parks) to allow PaDCNR to initially determine if data exist to make an objective evaluation of water resources for specific basins. The data compiled included water-quantity and water-quality data and sample locations for benthic macroinvertebrates within state-owned lands (including a 100-meter buffer around each land parcel) in Pennsylvania. In addition, internet links or contacts for geographic information system coverages pertinent to water-resources studies also were compiled. Water-quantity and water-quality data primarily available through January 2007 were compiled and summarized for site types that included streams, lakes, ground-water wells, springs, and precipitation. Data were categorized relative to 35 watershed boundaries defined by the Pennsylvania Department of Environmental Protection for resource-management purposes. The primary sources of continuous water-quantity data for Pennsylvania state lands were the U.S. Geological Survey (USGS) and the National Weather Service (NWS). The USGS has streamflow data for 93 surface-water sites located in state lands; 38 of these sites have continuous-recording data available. As of January 2007, 22 of these 38 streamflow-gaging stations were active; the majority of active gaging stations have over 40 years of continuous record. The USGS database also contains continuous ground-water elevation data for 32 wells in Pennsylvania state lands, 18 of which were active as of January 2007. Sixty-eight active precipitation stations (primarily from the NWS network) are located in state lands. The four sources of available water-quality data for Pennsylvania state lands were the USGS, U.S. Environmental Protection Agency, Pennsylvania Department of Environmental Protection (PaDEP), and the Susquehanna River Basin Commission. The water-quality data, which were primarily collected after 1970, were summarized by categorizing the analytical data for each site into major groups (for example, trace metals, pesticides, major ions, etc.) for each type (streams, lakes, ground-water wells, and springs) of data compiled. The number of samples and number of detections for each analyte within each group also were summarized. A total of 410 stream sites and 205 ground-water wells in state lands had water-quality data from the available data sets, and these sites were well-distributed across the state. A total of 107 lakes and 47 springs in state lands had water-quality data from the available data sets, but these data types were not well-distributed across the state; the majority of water-quality data for lakes was in the western or eastern sections of the state and water-quality data for springs was primarily located in the central part of the Lower Susquehanna River Valley. The most common types of water-quality data collected were major ions, trace elements, and nutrients. Physical parameters, such as water temperature, stream discharge, or water level, typically were collected for most water-quality samples. Given the large database available from PaDEP for benthic macroinvertebrates, along with some data from other agencies, there is very good distribution of benthic-macroinvertebrate data for state lands. Benthic macroinvertebrate samples were collected at 1,077 locations in state lands from 1973 to 2006. Most (980 samples) of the benthic-macroinvertebrate samples were collected by PaDEP as part of the state assessment of stream conditions required by the Clean Water Act. Data compiled in this report can be used for various water-resource issues, such as basin-wide water-budget analysis, studies of ecological or instream flow, or water-quality assessments. The determination of an annual water budget in selected basins is best supported by the availab
Determination of Methanol Concentrations in Traditional Herbal Waters of Different Brands in Iran
Mousavi, Seyed Reza; Namaei-Ghassemi, Mohssen; Layegh, Massomeh; AfzalAghaee, Monavar; vafaee, Manssoreh; Zare, Gholamali; Moghiman, Toktam; Mood, Mahdi Balali
2011-01-01
Objective(s) Herbal waters are extensively used in most parts of including . Visiting a patient with total blindness due to daily ingestion of around 200 ml of herbal water (Plant forty water) per day for six months was the rational for methanol determination in all herbal waters available in markets. Materials and Methods A total of two hundred and nineteen bottles of herbal waters were randomly bought from market. Methanol concentration was determined by gas chromatography, using a Flame Ionized Detector. Benzene (1000 mg/l) was applied as the internal standard. Collected data was analyzed by SPSS software (version 11.5), using appropriate descriptive statistical tests. Results Forty six different herbal waters from three main producing factories (A, B and C) were tested. Highest methanol concentration was measured in dill water of A (1208±202.74 mg/l), concentrated rose water of A (1017.41±59.68 mg/l) and concentrated rose water of B (978.52±92.81 mg/l). Lowest methanol concentration was determined in Trachyspermum copticum water of B (18.93±1.04 mg/l), cinnamon and ginger water of B (29.64±10.88 mg/l) and rice skin water of A (41.33±7.85 mg/l). Mean methanol concentrations of herbal waters including ginger, cinnamon, dill, peppermint, alfalfa, and plant forty from A, B and C were 374.69, 209.81 and 280.12 mg/l, respectively (P< 0.001). Conclusion Methanol concentration in all herbal waters, especially rose water of the three producers was very high that may induce toxicity in people taking these products regularly for a long time. PMID:23493100
NASA Astrophysics Data System (ADS)
Shiklomanov, A. I.; Prousevitch, A.; Sokolik, I. N.; Lammers, R. B.
2015-12-01
Water is a key agent in Central Asia ultimately determining human well-being, food security, and economic development. There are complex interplays among the natural and anthropogenic drivers effecting the regional hydrological processes and water availability. Analysis of the data combined from regional censuses and remote sensing shows a decline in areas of arable and irrigated lands and a significant decrease in availability of arable and irrigated lands per capita across all Central Asian countries since the middle of 1990thas the result of post-Soviet transformation processes. This change could lead to considerable deterioration in food security and human system sustainability. The change of political situation in the region has also resulted in the escalated problems of water demand between countries in international river basins. We applied the University of New Hampshire - Water Balance Model - Transport from Anthropogenic and Natural Systems (WBM-TrANS) to understand the consequences of changes in climate, water and land use on regional hydrological processes and water availability. The model accounts for sub-pixel land cover types, glacier and snow-pack accumulation/melt across sub-pixel elevation bands, anthropogenic water use (e.g. domestic and industrial consumption, and irrigation for most of existing crop types), hydro-infrastructure for inter-basin water transfer and reservoir/dam regulations. A suite of historical climate re-analysis and temporal extrapolation of MIRCA-2000 crop structure datasets has been used in WBM-TrANS for this project. A preliminary analysis of the model simulations over the last 30 years has shown significant spatial and temporal changes in hydrology and water availability for crops and human across the region due to climatic and anthropogenic causes. We found that regional water availability is mostly impacted by changes in extents and efficiency of crop filed irrigation, especially in highly arid areas of Central Asia, changes in winter snow storage, and shifts in seasonality and intensity of glacier melt waters driven by climatic changes.
SOFIA Water Vapor Monitor Design
NASA Technical Reports Server (NTRS)
Cooper, R.; Roellig, T. L.; Yuen, L.; Shiroyama, B.; Meyer, A.; Devincenzi, D. (Technical Monitor)
2002-01-01
The SOFIA Water Vapor Monitor (WVM) is a heterodyne radiometer designed to determine the integrated amount of water vapor along the telescope line of sight and directly to the zenith. The basic technique that was chosen for the WVM uses radiometric measurements of the center and wings of the 183.3 GHz rotational line of water to measure the water vapor. The WVM reports its measured water vapor levels to the aircraft Mission Controls and Communication System (MCCS) while the SOFIA observatory is in normal operation at flight altitude. The water vapor measurements are also available to other scientific instruments aboard the observatory. The electrical, mechanical and software design of the WVM are discussed.
18 CFR 420.23 - Exempt uses under the Compact.
Code of Federal Regulations, 2011 CFR
2011-04-01
... pumps, water lines and appurtenances installed and operable, determined according to sound engineering...) Whenever adequate records of legal entitlement for agricultural irrigation purposes are not available to...
18 CFR 420.23 - Exempt uses under the Compact.
Code of Federal Regulations, 2013 CFR
2013-04-01
... pumps, water lines and appurtenances installed and operable, determined according to sound engineering...) Whenever adequate records of legal entitlement for agricultural irrigation purposes are not available to...
18 CFR 420.23 - Exempt uses under the Compact.
Code of Federal Regulations, 2014 CFR
2014-04-01
... pumps, water lines and appurtenances installed and operable, determined according to sound engineering...) Whenever adequate records of legal entitlement for agricultural irrigation purposes are not available to...
18 CFR 420.23 - Exempt uses under the Compact.
Code of Federal Regulations, 2012 CFR
2012-04-01
... pumps, water lines and appurtenances installed and operable, determined according to sound engineering...) Whenever adequate records of legal entitlement for agricultural irrigation purposes are not available to...
Rousis, Nikolaos I; Bade, Richard; Bijlsma, Lubertus; Zuccato, Ettore; Sancho, Juan V; Hernandez, Felix; Castiglioni, Sara
2017-07-01
Assessing the presence of pesticides in environmental waters is particularly challenging because of the huge number of substances used which may end up in the environment. Furthermore, the occurrence of pesticide transformation products (TPs) and/or metabolites makes this task even harder. Most studies dealing with the determination of pesticides in water include only a small number of analytes and in many cases no TPs. The present study applied a screening method for the determination of a large number of pesticides and TPs in wastewater (WW) and surface water (SW) from Spain and Italy. Liquid chromatography coupled to high-resolution mass spectrometry (HRMS) was used to screen a database of 450 pesticides and TPs. Detection and identification were based on specific criteria, i.e. mass accuracy, fragmentation, and comparison of retention times when reference standards were available, or a retention time prediction model when standards were not available. Seventeen pesticides and TPs from different classes (fungicides, herbicides and insecticides) were found in WW in Italy and Spain, and twelve in SW. Generally, in both countries more compounds were detected in effluent WW than in influent WW, and in SW than WW. This might be due to the analytical sensitivity in the different matrices, but also to the presence of multiple sources of pollution. HRMS proved a good screening tool to determine a large number of substances in water and identify some priority compounds for further quantitative analysis. Copyright © 2017 Elsevier Inc. All rights reserved.
Collins, W.D.
1925-01-01
The importance of water supply as a limiting factor in industrial development is becoming more evident each year. The limitation in a particular instance may be the quantity of water available, the quality determined by the mineral matter in solution or in suspension or by organic pollution, or the temperature of the water. Generally it is a combination of two or more of these factors.Many publications of the Geological Survey give data in regard to the quantity of surface water and ground water obtainable at different points. Other publications of this Survey and of other organizations give data on the quality of waters available for industrial use. The temperature of these waters is discussed in the present report.Data in regard to ground water have been obtained from Geological Survey water-supply papers, from the publications indicated in footnotes, and from an unpublished compilation of temperature records prepared by C. E. Van Orstrand, of the Geological Survey, in connection with studies of deep earth temperature. Data on temperature of surface water have been obtained mainly from officials of waterworks, as noted in the accompanying table. Data on air temperature have been obtained from reports of the United States Weather Bureau. The maps showing temperature of ground water and surface water (Pls. VIII and IX) are taken directly from Weather Bureau charts of temperature distribution.
Development of a coastal drought index using salinity data
Paul Conrads; Lisa Darby
2016-01-01
The location of the freshwater-saltwater interface in surface-water bodies is an important factor in the ecological and socio-economic dynamics of coastal communities. It influences community composition in freshwater and saltwater ecosystems, determines fisheries spawning habitat, and controls freshwater availability for municipal and industrial water intakes. These...
Virginia R. Tolbert; Carl C. Trettin; Dale W. Johnson; John W. Parsons; Allan E. Houston; David A. Mays
2001-01-01
Ensuring sustainability of intensively managed woody crops requires determining soil and water quality effects using a combination of field data and modeling projections. Plot- and catchrnent-scale research, models, and meta-analyses are addressing nutrient availability, site quality, and measures to increase short-rotation woody crop (SRWC) productivity and site...
Nutrient availability constrains the hydraulic architecture and water relations of savannah trees.
S.J. Bucci; F.G. Scholz; G. Goldstein; F.C. Meinzer; A.C. Franco; P.I. Campanello; R. Villalobos-Vega; M. Bustamante; F. Miralles-Wilhelm
2006-01-01
Several plant functional traits were studied in five dominant woody savanna species in a Brazilian savanna to determine whether removal of nutrient limitations has an effect on carbon allocation, water relations, and hydraulic architecture. Four treatments consisting of a control, and nitrogen (N), phosphorus (P), and N plus P additions were maintained for 5 years....
Lum, W. E.; Turney, G.L.; Alvord, R.C.
1986-01-01
The Greenacres Landfill, located about 11 mi east of the city of Spokane, Washington, was used for the disposal of waste from 1951 to 1972. Materials in the landfill include household and industrial waste materials, and various hazardous wastes. In 1983 the landfill was designated by the U.S. EPA as a ' Superfund ' site. The purposes of this investigation were to gather, describe, and interpret all the existing data concerning the hydrology and groundwater quality of the area surrounding the landfill, and to identify any additional data needed to describe the hydrology of the area. The quantity of water flow through the landfill as a result of precipitation on the landfill and in the drainage basin above the landfill probably ranges from 21,000 to 85,000 gal/day. This water movement may be creating a leachate and transporting some of the wastes out of the landfill. The plume would encompass an area where groundwater provides most of the water used for municipal, industrial, irrigation, and domestic purposes. Water quality analyses of water from numerous wells in the area which are open to the Spokane aquifer are available, but well 25/45-16K1 is the only well where groundwater contamination was consistently apparent. This well is only 500 ft from the landfill. Contamination of water in this well was indicated by high concentrations of dissolved mineral constituents and several organic compounds, including trans-dichloroethene (115 to 392 micrograms/L). Available data are insufficient to completely interpret the groundwater flow system near this well and the source of the contamination cannot be determined conclusively. While the existing data are adequate to provide background information, more data are needed to: (1) determine the source of contamination in well 25/45-16K1; (2) determine groundwater flow in the Spokane aquifer near well 25/45-16K1; and (3) determine the extent of contamination in the Spokane aquifer. The degree of the influence of the landfill on the Spokane aquifer cannot be determined with existing data. (Author 's abstract)
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.
Fluoride availability from natural resources in The Gambia--implications for oral health care.
Jordan, Rainer A; Markovic, Ljubisa; Gaengler, Peter
2008-10-01
Changing food patterns in combination with ineffective oral hygiene measures and insufficient bioavailability of fluoride from drinking water and other sources seem to impair the dental health status in developing countries, especially in the younger population. Therefore, preventive programmes in controlling dental caries progression should be based on local conditions. For mapping the drinking water fluoride content throughout The Gambia, samples of water from rural community wells, public water taps, commercial mineral water, and from the Gambia-River were measured. Additionally, fluoride concentrations of locally extracted table salt and green tea were determined. Showed the need for supplementary fluoride intake, because natural dietary fluoride availability is very low. Age-related recommendations for oral health care and for additional fluoride bioavailability are given, taking into account local socio-economic conditions in the Republic of The Gambia and similar developing countries.
Ahmed, S A; Hoque, B A; Mahmud, A
1998-09-01
Although Bangladesh has achieved remarkable success in extending the availability of hand pumped and piped water, unsafe water is still ingested. This brief study attempted to assess water management practices in rural and urban homes in Bangladesh so as to establish the routes by which unsafe water is ingested, to examine methods of collection and storage, and determine why unsafe water sources are used when unsafe supplies are available. Forty-eight rural and forty-five urban slum households were studied. Observations, interviews and water quality investigations were conducted. The results show that the respondents were aware that hand pump/tap water is safe and took care to use these safe sources for drinking purposes. However, they continued to use surface water for non-drinking activities such as bathing, washing and rinsing their mouths. Reasons were given that it was a traditional practice to bathe in surface water and was more enjoyable. One of the reasons given for not using hand pumped water to wash clothing and food was that such groundwater caused staining. Bacteriological results from such ingested water showed the quality, especially in rural areas, to be poor. Results also showed the internal surfaces of the base of storage containers to be heavily contaminated with bacteria. This showed that water that was safe when it was first drawn would became contaminated during storage. This study had a limited scope; much further research is needed to find what determines and how water becomes contaminated in containers. These factors include how to reduce contamination of water, in particular the relationship between growth of bacteria in stored water and the material from which the container is made and how to improve the overall quality of water. On the management side, studies could be conducted as to how to improve people's understanding of the use of water for domestic purposes and its safe management.
46 CFR 56.50-55 - Bilge pumps.
Code of Federal Regulations, 2010 CFR
2010-10-01
...) Each self-propelled vessel must be provided with a power-driven pump or pumps connected to the bilge... power-driven pump is required. (See Part 171 of this chapter for determination of criterion numeral.) 5... available, or where a suitable water supply is available from a power-driven pump of adequate pressure and...
Lara A. Martin; Patrick J. Mulholland; Jackson R. Webster; H. Maurice Vallett
2001-01-01
We investigated variations in resource availability (NOa-N and labile organic C [LOCJ] as determinants of potential denitrification in stream sediments in the southern Appalachian Mountains, USA. stream-water and sediments were sampled seasonally in 2 streams of contrasting NO3,-N availability, Noland Creek (high NO
NASA Astrophysics Data System (ADS)
Djuwansyah, M. R.
2018-02-01
This paper reviews the use of Water Resources carrying capacity concept to control environmental sustainability with the particular note for the case in Indonesia. Carrying capacity is a capability measure of an environment or an area to support human and the other lives as well as their activities in a sustainable manner. Recurrently water-related hazards and environmental problems indicate that the environments are exploited over its carrying capacity. Environmental carrying capacity (ECC) assessment includes Land and Water Carrying Capacity analysis of an area, suggested to always refer to the dimension of the related watershed as an incorporated hydrologic unit on the basis of resources availability estimation. Many countries use this measure to forecast the future sustainability of regional development based on water availability. Direct water Resource Carrying Capacity (WRCC) assessment involves population number determination together with their activities could be supported by available water, whereas indirect WRCC assessment comprises the analysis of supply-demand balance status of water. Water resource limits primarily environmental carrying capacity rather than the land resource since land capability constraints are easier. WRCC is a crucial factor known to control land and water resource utilization, particularly in a growing densely populated area. Even though capability of water resources is relatively perpetual, the utilization pattern of these resources may change by socio-economic and cultural technology level of the users, because of which WRCC should be evaluated periodically to maintain usage sustainability of water resource and environment.
Scholl, Martha A.; Murphy, Sheila F.
2014-01-01
Like many mountainous areas in the tropics, watersheds in the Luquillo Mountains of eastern Puerto Rico have abundant rainfall and stream discharge and provide much of the water supply for the densely populated metropolitan areas nearby. Projected changes in regional temperature and atmospheric dynamics as a result of global warming suggest that water availability will be affected by changes in rainfall patterns. It is essential to understand the relative importance of different weather systems to water supply to determine how changes in rainfall patterns, interacting with geology and vegetation, will affect the water balance. To help determine the links between climate and water availability, stable isotope signatures of precipitation from different weather systems were established to identify those that are most important in maintaining streamflow and groundwater recharge. Precipitation stable isotope values in the Luquillo Mountains had a large range, from fog/cloud water with δ2H, δ18O values as high as +12 ‰, −0.73 ‰ to tropical storm rain with values as low as −127 ‰, −16.8 ‰. Temporal isotope values exhibit a reverse seasonality from those observed in higher latitude continental watersheds, with higher isotopic values in the winter and lower values in the summer. Despite the higher volume of convective and low-pressure system rainfall, stable isotope analyses indicated that under the current rainfall regime, frequent trade -wind orographic showers contribute much of the groundwater recharge and stream base flow. Analysis of rain events using 20 years of 15 -minute resolution data at a mountain station (643 m) showed an increasing trend in rainfall amount, in agreement with increased precipitable water in the atmosphere, but differing from climate model projections of drying in the region. The mean intensity of rain events also showed an increasing trend. The determination of recharge sources from stable isotope tracers indicates that water supply will be affected if regional atmospheric dynamics change trade- wind orographic rainfall patterns in the Caribbean.
Knobel, LeRoy L.
2006-01-01
This report presents qualitative and quantitative comparisons of water-quality data from the Idaho National Laboratory, Idaho, to determine if the change from purging three wellbore volumes to one wellbore volume has a discernible effect on the comparability of the data. Historical water-quality data for 30 wells were visually compared to water-quality data collected after purging only 1 wellbore volume from the same wells. Of the 322 qualitatively examined constituent plots, 97.5 percent met 1 or more of the criteria established for determining data comparability. A simple statistical equation to determine if water-quality data collected from 28 wells at the INL with long purge times (after pumping 1 and 3 wellbore volumes of water) were statistically the same at the 95-percent confidence level indicated that 97.9 percent of 379 constituent pairs were equivalent. Comparability of water-quality data determined from both the qualitative (97.5 percent comparable) and quantitative (97.9 percent comparable) evaluations after purging 1 and 3 wellbore volumes of water indicates that the change from purging 3 to 1 wellbore volumes had no discernible effect on comparability of water-quality data at the INL. However, the qualitative evaluation was limited because only October-November 2003 data were available for comparison to historical data. This report was prepared by the U.S. Geological Survey in cooperation with the U.S. Department of Energy.
McCluney, Kevin E; Belnap, Jayne; Collins, Scott L; González, Angélica L; Hagen, Elizabeth M; Nathaniel Holland, J; Kotler, Burt P; Maestre, Fernando T; Smith, Stanley D; Wolf, Blair O
2012-08-01
Species interactions play key roles in linking the responses of populations, communities, and ecosystems to environmental change. For instance, species interactions are an important determinant of the complexity of changes in trophic biomass with variation in resources. Water resources are a major driver of terrestrial ecology and climate change is expected to greatly alter the distribution of this critical resource. While previous studies have documented strong effects of global environmental change on species interactions in general, responses can vary from region to region. Dryland ecosystems occupy more than one-third of the Earth's land mass, are greatly affected by changes in water availability, and are predicted to be hotspots of climate change. Thus, it is imperative to understand the effects of environmental change on these globally significant ecosystems. Here, we review studies of the responses of population-level plant-plant, plant-herbivore, and predator-prey interactions to changes in water availability in dryland environments in order to develop new hypotheses and predictions to guide future research. To help explain patterns of interaction outcomes, we developed a conceptual model that views interaction outcomes as shifting between (1) competition and facilitation (plant-plant), (2) herbivory, neutralism, or mutualism (plant-herbivore), or (3) neutralism and predation (predator-prey), as water availability crosses physiological, behavioural, or population-density thresholds. We link our conceptual model to hypothetical scenarios of current and future water availability to make testable predictions about the influence of changes in water availability on species interactions. We also examine potential implications of our conceptual model for the relative importance of top-down effects and the linearity of patterns of change in trophic biomass with changes in water availability. Finally, we highlight key research needs and some possible broader impacts of our findings. Overall, we hope to stimulate and guide future research that links changes in water availability to patterns of species interactions and the dynamics of populations and communities in dryland ecosystems. © 2011 The Authors. Biological Reviews © 2011 Cambridge Philosophical Society.
Sadiq, Rehan; Husain, Tahir; Veitch, Brian; Bose, Neil
2003-12-01
Due to the hydrophobic nature of synthetic based fluids (SBFs), drilling cuttings are not very dispersive in the water column and settle down close to the disposal site. Arsenic and copper are two important toxic heavy metals, among others, found in the drilling waste. In this article, the concentrations of heavy metals are determined using a steady state "aquivalence-based" fate model in a probabilistic mode. Monte Carlo simulations are employed to determine pore water concentrations. A hypothetical case study is used to determine the water quality impacts for two discharge options: 4% and 10% attached SBFs, which correspond to the best available technology option and the current discharge practice in the U.S. offshore. The exposure concentration (CE) is a predicted environmental concentration, which is adjusted for exposure probability and bioavailable fraction of heavy metals. The response of the ecosystem (RE) is defined by developing an empirical distribution function of predicted no-effect concentration. The pollutants' pore water concentrations within the radius of 750 m are estimated and cumulative distributions of risk quotient (RQ=CE/RE) are developed to determine the probability of RQ greater than 1.
Rothstein, Jessica D; Leontsini, Elli; Olortegui, Maribel Paredes; Yori, Pablo Peñataro; Surkan, Pamela J; Kosek, Margaret
2015-09-01
The gap between the efficacy and the effectiveness of household water treatment in reducing diarrhea-related morbidity indicates the need for a better understanding of the determinants of long-term behavior change. To explore the barriers to drinking water chlorination in the Peruvian Amazon, where diarrhea is endemic among under-5 children, we conducted qualitative research with 23 caregivers from peri-urban communities of Iquitos, Peru. Our inquiry drew on the Transtheoretical Model of behavior change and the Integrated Behavioral Model for Water, Sanitation, and Hygiene to identify the most relevant contextual, psychosocial, and technological determinants of initial action and long-term adoption of chlorination. Our findings suggest that the decision to try out this practice resulted from the combined effect of knowledge of chlorination benefits and product availability and affordability. Progress from action to adoption was influenced by caretakers' understanding of dosage, the packaging of chlorine products, knowledge and skills for multipurpose laundry bleach, the taste of treated water, and reinforcement. This analysis suggests that a focus on these determinants and the household domain may help to improve the sustainability of future intervention efforts. © The American Society of Tropical Medicine and Hygiene.
Rothstein, Jessica D.; Leontsini, Elli; Olortegui, Maribel Paredes; Yori, Pablo Peñataro; Surkan, Pamela J.; Kosek, Margaret
2015-01-01
The gap between the efficacy and the effectiveness of household water treatment in reducing diarrhea-related morbidity indicates the need for a better understanding of the determinants of long-term behavior change. To explore the barriers to drinking water chlorination in the Peruvian Amazon, where diarrhea is endemic among under-5 children, we conducted qualitative research with 23 caregivers from peri-urban communities of Iquitos, Peru. Our inquiry drew on the Transtheoretical Model of behavior change and the Integrated Behavioral Model for Water, Sanitation, and Hygiene to identify the most relevant contextual, psychosocial, and technological determinants of initial action and long-term adoption of chlorination. Our findings suggest that the decision to try out this practice resulted from the combined effect of knowledge of chlorination benefits and product availability and affordability. Progress from action to adoption was influenced by caretakers' understanding of dosage, the packaging of chlorine products, knowledge and skills for multipurpose laundry bleach, the taste of treated water, and reinforcement. This analysis suggests that a focus on these determinants and the household domain may help to improve the sustainability of future intervention efforts. PMID:26175028
77 FR 18846 - Proposed Flood Hazard Determinations
Federal Register 2010, 2011, 2012, 2013, 2014
2012-03-28
... panels of experts in hydrology, hydraulics, and other pertinent sciences established to review... Incorporated Areas Maps Available for Inspection Online at: http://www.dnr.sc.gov/water/flood/comaps.html City...
78 FR 5824 - Proposed Flood Hazard Determinations
Federal Register 2010, 2011, 2012, 2013, 2014
2013-01-28
... resolution process. SRPs are independent panels of experts in hydrology, hydraulics, and other pertinent..., and Incorporated Areas Maps Available for Inspection Online at: http://www.in.gov/dnr/water/6396.htm...
Physiological Plasticity Is Important for Maintaining Sugarcane Growth under Water Deficit
Marchiori, Paulo E. R.; Machado, Eduardo C.; Sales, Cristina R. G.; Espinoza-Núñez, Erick; Magalhães Filho, José R.; Souza, Gustavo M.; Pires, Regina C. M.; Ribeiro, Rafael V.
2017-01-01
The water availability at early phenological stages is critical for crop establishment and sugarcane varieties show differential performance under drought. Herein, we evaluated the relative importance of morphological and physiological plasticity of young sugarcane plants grown under water deficit, testing the hypothesis that high phenotypic plasticity is associated with drought tolerance. IACSP95-5000 is a high yielding genotype and IACSP94-2094 has good performance under water limiting environments. Plants were grown in rhizotrons for 35 days under three water availabilities: high (soil water matric potential [Ψm] higher than -20 kPa); intermediate (Ψm reached -65 and -90 kPa at the end of experimental period) and low (Ψm reached values lower than -150 kPa). Our data revealed that morphological and physiological responses of sugarcane to drought are dependent on genotype and intensity of water deficit. In general, IACSP95-5000 showed higher physiological plasticity given by leaf gas exchange and photochemical traits, whereas IACSP94-2094 showed higher morphological plasticity determined by changes in leaf area (LA) and specific LA. As IACSP94-2094 accumulated less biomass than IACSP95-5000 under varying water availability, it is suggested that high morphological plasticity does not always represent an effective advantage to maintain plant growth under water deficit. In addition, our results revealed that sugarcane varieties face water deficit using distinct strategies based on physiological or morphological changes. When the effectiveness of those changes in maintaining plant growth under low water availability is taken into account, our results indicate that the physiological plasticity is more important than the morphological one in young sugarcane plants. PMID:29326744
Plant–Water Relations (1): Uptake and Transport
2014-01-01
Summary Plants, like all living things, are mostly water. Water is the matrix of life, and its availability determines the distribution and productivity of plants on earth. Vascular plants evolved structures that enable them to transport water long distances with little input of energy, but the hollow tracheary elements are just one of many adaptations that enable plants to cope with a very dry atmosphere. This lecture examines the physical laws that govern water uptake and transport, the biological properties of cells and plant tissues that facilitate it, and the strategies that enable plants to survive in diverse environments
NASA Astrophysics Data System (ADS)
Nazemi, A.; Wheater, H. S.
2015-01-01
Human activities have caused various changes to the Earth system, and hence the interconnections between human activities and the Earth system should be recognized and reflected in models that simulate Earth system processes. One key anthropogenic activity is water resource management, which determines the dynamics of human-water interactions in time and space and controls human livelihoods and economy, including energy and food production. There are immediate needs to include water resource management in Earth system models. First, the extent of human water requirements is increasing rapidly at the global scale and it is crucial to analyze the possible imbalance between water demands and supply under various scenarios of climate change and across various temporal and spatial scales. Second, recent observations show that human-water interactions, manifested through water resource management, can substantially alter the terrestrial water cycle, affect land-atmospheric feedbacks and may further interact with climate and contribute to sea-level change. Due to the importance of water resource management in determining the future of the global water and climate cycles, the World Climate Research Program's Global Energy and Water Exchanges project (WRCP-GEWEX) has recently identified gaps in describing human-water interactions as one of the grand challenges in Earth system modeling (GEWEX, 2012). Here, we divide water resource management into two interdependent elements, related firstly to water demand and secondly to water supply and allocation. In this paper, we survey the current literature on how various components of water demand have been included in large-scale models, in particular land surface and global hydrological models. Issues of water supply and allocation are addressed in a companion paper. The available algorithms to represent the dominant demands are classified based on the demand type, mode of simulation and underlying modeling assumptions. We discuss the pros and cons of available algorithms, address various sources of uncertainty and highlight limitations in current applications. We conclude that current capability of large-scale models to represent human water demands is rather limited, particularly with respect to future projections and coupled land-atmospheric simulations. To fill these gaps, the available models, algorithms and data for representing various water demands should be systematically tested, intercompared and improved. In particular, human water demands should be considered in conjunction with water supply and allocation, particularly in the face of water scarcity and unknown future climate.
Collins, Luke; Bradstock, Ross A; Resco de Dios, Victor; Duursma, Remko A; Velasco, Sabrina; Boer, Matthias M
2018-06-01
Rising atmospheric [CO 2 ] and associated climate change are expected to modify primary productivity across a range of ecosystems globally. Increasing aridity is predicted to reduce grassland productivity, although rising [CO 2 ] and associated increases in plant water use efficiency may partially offset the effect of drying on growth. Difficulties arise in predicting the direction and magnitude of future changes in ecosystem productivity, due to limited field experimentation investigating climate and CO 2 interactions. We use repeat near-surface digital photography to quantify the effects of water availability and experimentally manipulated elevated [CO 2 ] (eCO 2 ) on understorey live foliage cover and biomass over three growing seasons in a temperate grassy woodland in south-eastern Australia. We hypothesised that (i) understorey herbaceous productivity is dependent upon soil water availability, and (ii) that eCO 2 will increase productivity, with greatest stimulation occurring under conditions of low water availability. Soil volumetric water content (VWC) determined foliage cover and growth rates over the length of the growing season (August to March), with low VWC (<0.1 m 3 m -3 ) reducing productivity. However, eCO 2 did not increase herbaceous cover and biomass over the duration of the experiment, or mitigate the effects of low water availability on understorey growth rates and cover. Our findings suggest that projected increases in aridity in temperate woodlands are likely to lead to reduced understorey productivity, with little scope for eCO 2 to offset these changes. © 2018 John Wiley & Sons Ltd.
Fluoride and bacterial content of bottled drinking water versus municipal tap water.
Mythri, H; Chandu, G N; Prashant, G M; Subba Reddy, V V
2010-01-01
Water is a divine gift. People quench their thirst without questioning the source of water. But, apprehension about contaminants in municipal water supplies along with increased fear of fluorosis made bottled drinking water as one of the important tradable commodities. The objectives of the study were to determine and compare the fluoride and bacterial contents of commercially available bottled drinking water and municipal tap water in Davangere city, Karnataka. Fifty samples of 10 categories of bottled drinking water with different batch numbers were purchased and municipal water from different sources were collected. Fluoride levels were determined by an ion-selective electrode. Water was cultured quantitatively and levels of bacteria were calculated as colony-forming units (CFUs) per milliliter. Descriptive analysis of water samples for fluoride concentration was in the range of 0.07-0.33 for bottled drinking water, Bisleri showing the highest of 0.33. A comparison of the mean values of microbial count for bottled drinking water with that of municipal tap water showed no statistically significant difference, but was more than the standard levels along with the presence of fungus and maggots. The fluoride concentration was below the optimal level for both municipal tap water and bottled drinking water. CFUs were more than the recommended level in both municipal tap water and bottled drinking water.
Fracasso, Alessandra; Magnanini, Eugenio; Marocco, Adriano; Amaducci, Stefano
2017-01-01
Plant growth and productivity are strongly affected by limited water availability in drought prone environments. The current climate change scenario, characterized by long periods without precipitations followed by short but intense rainfall, forces plants to implement different strategies to cope with drought stress. Understanding how plants use water during periods of limited water availability is of primary importance to identify and select the best adapted genotypes to a certain environment. Two sorghum genotypes IS22330 and IS20351, previously characterized as drought tolerant and drought sensitive genotypes, were subjected to progressive drought stress through a dry-down experiment. A whole-canopy multi-chamber system was used to determine the in vivo water use efficiency (WUE). This system records whole-canopy net photosynthetic and transpiration rate of 12 chambers five times per hour allowing the calculation of whole-canopy instantaneous WUE daily trends. Daily net photosynthesis and transpiration rates were coupled with gene expression dynamics of five drought related genes. Under drought stress, the tolerant genotype increased expression level for all the genes analyzed, whilst the opposite trend was highlighted by the drought sensitive genotype. Correlation between gene expression dynamics and gas exchange measurements allowed to identify three genes as valuable candidate to assess drought tolerance in sorghum.
Fracasso, Alessandra; Magnanini, Eugenio; Marocco, Adriano; Amaducci, Stefano
2017-01-01
Plant growth and productivity are strongly affected by limited water availability in drought prone environments. The current climate change scenario, characterized by long periods without precipitations followed by short but intense rainfall, forces plants to implement different strategies to cope with drought stress. Understanding how plants use water during periods of limited water availability is of primary importance to identify and select the best adapted genotypes to a certain environment. Two sorghum genotypes IS22330 and IS20351, previously characterized as drought tolerant and drought sensitive genotypes, were subjected to progressive drought stress through a dry-down experiment. A whole-canopy multi-chamber system was used to determine the in vivo water use efficiency (WUE). This system records whole-canopy net photosynthetic and transpiration rate of 12 chambers five times per hour allowing the calculation of whole-canopy instantaneous WUE daily trends. Daily net photosynthesis and transpiration rates were coupled with gene expression dynamics of five drought related genes. Under drought stress, the tolerant genotype increased expression level for all the genes analyzed, whilst the opposite trend was highlighted by the drought sensitive genotype. Correlation between gene expression dynamics and gas exchange measurements allowed to identify three genes as valuable candidate to assess drought tolerance in sorghum. PMID:28620409
Murrell, Ebony G.; Damal, Kavitha; Lounibos, L. P.; Juliano, Steven A.
2012-01-01
Coexistence of competitors may result if resources are sufficiently abundant to render competition unimportant, or if species differ in resource requirements. Detritus type has been shown to affect interspecific competitive outcomes between Aedes albopictus (Skuse) and Aedes aegypti (L.) larvae under controlled conditions. We assessed the relationships among spatial distributions of detritus types, nutrients, and aquatic larvae of these species in nature. We collected mosquitoes, water, and detritus from artificial containers across 24 Florida cemeteries that varied in relative abundances of Ae. aegypti and Ae. albopictus.We measured nutrient content of fine particulate organic matter in water samples as total N, P, and C and ratios of these nutrients. We quantified food availability via a bioassay, raising individual Aedes larvae in the laboratory in standard volumes of field-collected, particulate-containing water from each cemetery. Quantities of detritus types collected in standard containers were significant predictors of nutrients and nutrient ratios. Nutrient abundances were significant predictors of relative abundance of Ae. aegypti, and of larval survival and development by both species in the bioassay. Survival and development of larvae reared in particulate-containing water from sites decreased with decreasing relative abundance of Ae. aegypti. These data suggest that N, P, and C availabilities are determined by detritus inputs to containers and that these nutrients in turn determine the feeding environment encountered by larvae, the intensity of interspecific competition among larvae, and subsequent relative abundances of species at sites. Detritus inputs, nutrients, and food availability thus seem to contribute to distributions of Ae. aegypti and Ae. albopictus in cemetery containers throughout Florida. PMID:22707761
Ede, Alison Okorie; Nwaokoro, Joakin Chidozie; Iwuala, C C; Amadi, A N; Akpelu, Ugochinyere Alvana
2014-10-01
Guinea worm is a parasite found in unprotected drinking water sources, causes considerable morbidity and loss of agricultural production among rural people. The study was to determine the current status of Guinea worm infection in Ezza North and to evaluate the impact of control measures on guinea worm infection. A total of 200 individuals in Ezza North Southeastern, Nigeria were examined for guinea worm infection. A standardized questionnaire was used to determine the effect of potable water on guinea worm eradication/control, the source of drinking water, information on the knowledge, attitude, symptom management practices, availability of health facilities and boreholes installation status. The instrument for data collection was well constructed, validated and reliable tested questionnaire by an expert. Data obtained was analyzed using Epi-Info model 3.4 versions. Results of a study indicated majority of the respondents 195 (97.5 %) have access to safe drinking water supply which indicated no case of Guinea worm infection. The active use of potable water supply was found among the age group of 20-30 years 71 (35.5 %) and higher in male (57.5 %) than females (42.5 %). The drastic reduction of Guinea worm infection to zero (0) level in Ezza North were due to multiple factors as health education, availability of functional boreholes, presence of health centers for immediate treatment if any case discovered.
Mullaney, John R.
2004-01-01
Ground-water budgets were developed for 32 small basin-based zones in the Greenwich area of southwestern Connecticut, where crystalline-bedrock aquifers supply private wells, to determine the status of residential ground-water consumption relative to rates of ground-water recharge and discharge. Estimated residential ground-water withdrawals for small basins (averaging 1.7 square miles (mi2)) ranged from 0 to 0.16 million gallons per day per square mile (Mgal/d/mi2). To develop these budgets, residential ground-water withdrawals were estimated using multiple-linear regression models that relate water use from public water supply to data on residential property characteristics. Average daily water use of households with public water supply ranged from 219 to 1,082 gallons per day (gal/d). A steady-state finite-difference ground-water- flow model was developed to track water budgets, and to estimate optimal values for hydraulic conductivity of the bedrock (0.05 feet per day) and recharge to the overlying till deposits (6.9 inches) using nonlinear regression. Estimated recharge rates to the small basins ranged from 3.6 to 7.5 inches per year (in/yr) and relate to the percentage of the basin underlain by coarse- grained glacial stratified deposits. Recharge was not applied to impervious areas to account for the effects of urbanization. Net residential ground-water consumption was estimated as ground-water withdrawals increased during the growing season, and ranged from 0 to 0.9 in/yr. Long-term average stream base flows simulated by the ground-water-flow model were compared to calculated values of average base flow and low flow to determine if base flow was substantially reduced in any of the basins studied. Three of the 32 basins studied had simulated base flows less than 3 in/yr, as a result of either ground-water withdrawals or reduced recharge due to urbanization. A water-availability criteria of the difference between the 30-day 2-year low flow and the recharge rate for each basin was explored as a method to rate the status of water consumption in each basin. Water consumption ranged from 0 to 14.3 percent of available water based on this criteria for the 32 basins studied. Base-flow water quality was related to the amount of urbanized area in each basin sampled. Concentrations of total nitrogen and phosphorus, chloride, indicator bacteria, and the number of pesticide detections increased with basin urbanization, which ranged from 18 to 63 percent of basin area.
NASA Astrophysics Data System (ADS)
Prasch, M.; Mauser, W.; Weber, M.
2012-10-01
Water supply of most lowland cultures heavily depends on rain and melt-water from the upstream mountains. Especially melt-water release of alpine mountain ranges is usually attributed a pivotal role for the water supply of large downstream regions. Water scarcity is assumed as consequence of glacier shrinkage and possible disappearance due to Global Climate Change, particular for large parts of Central and South East Asia. In this paper, the application and validation of a coupled modeling approach with Regional Climate Model outputs and a process-oriented glacier and hydrological model is presented for a Central Himalayan river basin despite scarce data availability. Current and possible future contributions of ice-melt to runoff along the river network are spatially explicitly shown. Its role among the other water balance components is presented. Although glaciers have retreated and will continue to retreat according to the chosen climate scenarios, water availability is and will be primarily determined by monsoon precipitation and snow-melt. Ice-melt from glaciers is and will be a minor runoff component in summer monsoon-dominated Himalayan river basins.
Tavčar, Eva; Turk, Erika; Kreft, Samo
2012-01-01
The most commonly used technique for water content determination is Karl-Fischer titration with electrometric detection, requiring specialized equipment. When appropriate equipment is not available, the method can be performed through visual detection of a titration endpoint, which does not enable an analysis of colored samples. Here, we developed a method with spectrophotometric detection of a titration endpoint, appropriate for moisture determination of colored samples. The reaction takes place in a sealed 4 ml cuvette. Detection is performed at 520 nm. Titration endpoint is determined from the graph of absorbance plotted against titration volume. The method has appropriate reproducibility (RSD = 4.3%), accuracy, and linearity (R 2 = 0.997). PMID:22567558
Harvey, Judson W.; Krupa, S.L.; Gefvert, C.J.; Choi, Jungyill; Mooney, R.H.; Giddings, J.B.
2000-01-01
The data presented in this report are products of an investigation that quantified interactions between ground water and surface water at several study sites in the northern Everglades. Goals included identifying the major geologic controls and human alterations that affect interactions between ground water and surface water, and determining how those interactions affect mercury contamination. The primary study area was the 3,815-acre Everglades Nutrient Removal (ENR), a wetland constructed in the early 1990s as a prototype Stormwater Treatment Area (STA), to determine the effectiveness in removing excess nutrients from agricultural drainage. In order to ensure that results from ENR are broadly informative, work was also conducted in Water Conservation Area-2A (WCA-2A), a 105,000-acre basin surrounded by levees. In the past 50 years, WCA-2A has experienced extensive re- engineering of water flow, alterations in the pattern of water-level fluctuations and timing of fire frequency, as well as substantial ecological changes. The most visible ecological alteration is the change in dominance over the past 30 years from a sawgrass wetland to cattail wetland in the northeastern part of WCA-2A. The drastic change in vegetation in WCA-2A resulted at least in part from inputs of excess phosphorus from agricultural drainage. Substantial data collection programs were already in progress in both ENR and WCA- 2A when the present work began. The South Florida Water Management District (SFWMD) constructed the ENR project in 1994 to determine the effectiveness of constructed wetlands for water treatment. Measurements of surface water flow and water quality were made frequently in ENR between 1994 and 1998. Fewer ground water data were collected at ENR, and almost all of it was collected from shallow wells emplaced on perimeter levees. In contrast to the short-term nature of data collection in ENR, hydrologic and chemical data were collected over a much longer period in WCA-2A (since at least the mid- 1970s), but the number of sites and data- collection frequency is much less. Very little prior ground water data were available in WCA-2A. Given the availability of prior information, the present study emphasized the collection of ground water field data, particularly in the interior wetland areas of ENR and WCA- 2A. New wells were emplaced to permit the geologic, hydraulic, and chemical sampling that was needed to characterize interactions between surface water and ground water. In particular, lithology and hydraulic properties of the Surficial aquifer were determined, ground water flow paths and velocities were delineated, hydrologic fluxes between surface water and ground water were measured, and water budgets and surface- subsurface fluxes of mercury were determined. The purpose of this report is to compile under one cover all of the data collected in this investigation. In addition, the report contains a detailed description of the study methods and information about study sites, borehole drilling, well construction, seepage meter installation, and hydraulic and geochemical chemical sampling. Data interpretations are the subject of a companion report.
NASA Astrophysics Data System (ADS)
White, D. M.; Strang, E. T.; Alessa, L.; Hinzman, L.; Kliskey, A.
2005-12-01
The objective of this research is to understand how humans rely on freshwater at local and regional scales in selected parts of the Arctic, how these dependencies have changed in the recent past, and how they are likely to change in the future. The study seeks to incorporate likely effects of climate change on the hydrologic cycle and water availability to humans in the Arctic. The human demand for freshwater has risen dramatically over the past hundred years. Communities on the Seward Peninsula currently rely on both treated and traditional water sources for their drinking water. In many cases, availability of freshwater limits the use of both of these types of water sources. Future water demand predictions suggest that the demand for treated water will increase significantly as water systems are upgraded and the population of the area increases. Preliminary research indicates that water quality may by impacted by hydrologic changes, and further research is underway to determine the extent of these changes and how they will affect drinking water supplies on the Seward Peninsula. Understanding how climate change will impact the hydrology of this area will help minimize the impact these changes have on both engineered water systems and traditional water uses in the future. This presentation provides the most recent results of this research program. This study is being funded under the NSF Arctic System Science Program, Human Dimensions of the Arctic (OPP-0328686).
Literature Review on Processing and Analytical Methods for ...
Report The purpose of this report was to survey the open literature to determine the current state of the science regarding the processing and analytical methods currently available for recovery of F. tularensis from water and soil matrices, and to determine what gaps remain in the collective knowledge concerning F. tularensis identification from environmental samples.
Paetsch, Lydia; Mueller, Carsten W; Kögel-Knabner, Ingrid; von Lützow, Margit; Girardin, Cyril; Rumpel, Cornelia
2018-05-01
Biochar (BC) amendments may be suitable to increase the ecosystems resistance to drought due to their positive effects on soil water retention and availability. We investigated the effect of BC in situ ageing on water availability and microbial parameters of a grassland soil. We used soil containing 13 C labeled BC and determined its water holding capacity, microbial biomass and activity during a 3 months incubation under optimum and drought conditions. Our incubation experiment comprised three treatments: soil without BC (Control), soil containing aged BC (BC aged ) and soil containing fresh BC (BC fresh ), under optimum soil water (pF 1.8) and drought conditions (pF 3.5). Under optimum water as well as drought conditions, soils containing BC showed higher soil organic carbon (SOC) mineralization as compared to control soil. Moreover, BC effects on the soil water regime increase upon in situ aging. Native SOC mineralization increased most for soils containing BC aged . The BC aged led to improved C use under drought as compared to the other treatments. We conclude that BC addition to soils can ameliorate their water regime, especially under drought conditions. This beneficial effect of BC increases upon its aging, which also improved native substrate availability.
NASA Astrophysics Data System (ADS)
Li, Mo; Fu, Qiang; Singh, Vijay P.; Ma, Mingwei; Liu, Xiao
2017-12-01
Water scarcity causes conflicts among natural resources, society and economy and reinforces the need for optimal allocation of irrigation water resources in a sustainable way. Uncertainties caused by natural conditions and human activities make optimal allocation more complex. An intuitionistic fuzzy multi-objective non-linear programming (IFMONLP) model for irrigation water allocation under the combination of dry and wet conditions is developed to help decision makers mitigate water scarcity. The model is capable of quantitatively solving multiple problems including crop yield increase, blue water saving, and water supply cost reduction to obtain a balanced water allocation scheme using a multi-objective non-linear programming technique. Moreover, it can deal with uncertainty as well as hesitation based on the introduction of intuitionistic fuzzy numbers. Consideration of the combination of dry and wet conditions for water availability and precipitation makes it possible to gain insights into the various irrigation water allocations, and joint probabilities based on copula functions provide decision makers an average standard for irrigation. A case study on optimally allocating both surface water and groundwater to different growth periods of rice in different subareas in Heping irrigation area, Qing'an County, northeast China shows the potential and applicability of the developed model. Results show that the crop yield increase target especially in tillering and elongation stages is a prevailing concern when more water is available, and trading schemes can mitigate water supply cost and save water with an increased grain output. Results also reveal that the water allocation schemes are sensitive to the variation of water availability and precipitation with uncertain characteristics. The IFMONLP model is applicable for most irrigation areas with limited water supplies to determine irrigation water strategies under a fuzzy environment.
Estimating plant available water content from remotely sensed evapotranspiration
NASA Astrophysics Data System (ADS)
van Dijk, A. I. J. M.; Warren, G.; Doody, T.
2012-04-01
Plant available water content (PAWC) is an emergent soil property that is a critical variable in hydrological modelling. PAWC determines the active soil water storage and, in water-limited environments, is the main cause of different ecohydrological behaviour between (deep-rooted) perennial vegetation and (shallow-rooted) seasonal vegetation. Conventionally, PAWC is estimated for a combination of soil and vegetation from three variables: maximum rooting depth and the volumetric water content at field capacity and permanent wilting point, respectively. Without elaborate local field observation, large uncertainties in PAWC occur due to the assumptions associated with each of the three variables. We developed an alternative, observation-based method to estimate PAWC from precipitation observations and CSIRO MODIS Reflectance-based Evapotranspiration (CMRSET) estimates. Processing steps include (1) removing residual systematic bias in the CMRSET estimates, (2) making spatially appropriate assumptions about local water inputs and surface runoff losses, (3) using mean seasonal patterns in precipitation and CMRSET to estimate the seasonal pattern in soil water storage changes, (4) from these, calculating the mean seasonal storage range, which can be treated as an estimate of PAWC. We evaluate the resulting PAWC estimates against those determined in field experiments for 180 sites across Australia. We show that the method produces better estimates of PAWC than conventional techniques. In addition, the method provides detailed information with full continental coverage at moderate resolution (250 m) scale. The resulting maps can be used to identify likely groundwater dependent ecosystems and to derive PAWC distributions for each combination of soil and vegetation type.
Dursun, Derya; Ozkul, Selin; Yuksel, Recep; Unalan, Husnu Emrah
2017-02-01
In recent years, capacitive deionization (CDI) has been reported as one of the emerging technologies developed with the purpose of water desalination. This work is aimed at the integration of supercapacitor electrodes for efficient removal of ions from water, and thus to achieve an energy efficient, and cost-effective water treatment process. Our objective is to transfer the vast knowledge of supercapacitors and advanced materials in area of water treatment to enhance the knowledge of the CDI process. Towards the main purpose, graphene-based supercapacitor electrodes were developed from commercially available, cost-effective graphene and the use of these new materials for deionization was explored in detail. The porosity, morphology and electrochemical characteristics of the active materials were confirmed by Brunauer-Emmett-Teller method, scanning electron microscopy, Raman spectroscopy and chronoamperometry. Furthermore, the deionization performances of the graphene electrodes were evaluated by a laboratory scale CDI unit. The ion sorption behavior of the electrode was analyzed at different electrical potentials and flow rates. Impact of operating parameters on the sorption capacity was determined. At 20 mL/min flow rate and 2.0 V potential, the electrosorptive capacity of commercially available graphene electrodes could reach 12.5 μmol/g. Our results indicated the ability to use commercially available graphene for deionization purpose.
NASA Astrophysics Data System (ADS)
Arciniega, S.; Breña-Naranjo, J. A.; Hernaández Espriú, A.; Pedrozo-Acuña, A.
2017-12-01
Mexico has significant shale oil and gas resources mainly contained within the Mexican part of the Eagle Ford play (Mex-EF), in the Burgos Basin located in northern Mexico. Over the last years, concerns about the water use associated to shale gas development using hydraulic fracturing (HF) have been increasing in the United States and Canada. In Mexico, the recent approval of a new energy bill allows the exploration, development and production of shale gas reserves. However, several of the Mexican shale gas resources are located in water-limited environments, such as the Mex-EF. The lack of climate and hydrological gauging stations across this region constrains information about how much freshwater from surface and groundwater sources is available and whether its interannual water availability is sufficient to satisfy the water demand by other users (agricultural, urban) of the region This work projects the water availability across the Mex-EF and its water use derived from the expansion of unconventional gas developments over the next 15 years. Water availability is estimated using a water balance approach, where the irrigation's groundwater withdrawals time series were reconstructed using remote sensing products (vegetation index and hydrological outputs from LSMs) and validated with in situ observed water use at three different irrigation districts of the region. Water use for HF is inferred using type curves of gas production, flowback and produced (FP) water and curves of drilled wells per year from the US experience, mainly from the Texas-EF play. Scenarios that combine freshwater use and FP water use for HF are developed and the spatial distribution of HF well pads is projected using random samples with a range of wells' horizontal length. This proposed methodology can be applied in other shale formations of the world under water stress and it also helps to determine whether water scarcity can be a limiting factor for the shale gas industry over the next decades. Image already added
Wätjen, U; Benedik, L; Spasova, Y; Vasile, M; Altzitzoglou, T; Beyermann, M
2010-01-01
In anticipation of new European requirements for monitoring radioactivity concentration in drinking water, IRMM organized an interlaboratory comparison on the determination of low levels of activity concentrations (about 10-100 mBq L(-1)) of the naturally occurring radionuclides (226)Ra, (228)Ra, (234)U and (238)U in three commercially available mineral waters. Using two or three different methods with traceability to the International System of Reference (SIR), the reference values of the water samples were determined prior to the proficiency test within combined standard uncertainties of the order of 3%-10%. An overview of radiochemical separation and measurement methods used by the 45 participating laboratories are given. The results of the participants are evaluated versus the reference values. Several of the participants' results deviate by more than a factor of two from the reference values, in particular for the radium isotopes. Such erroneous analysis results may lead to a crucial omission of remedial actions on drinking water supplies or to economic loss by an unjustified action. Copyright 2009 Elsevier Ltd. All rights reserved.
Ball, James W.; Nordstrom, D. Kirk; Jenne, Everett A.; Vivit, Davison V.
1998-01-01
This report presents all analytical determinations for samples collected from Yellowstone National Park and vicinity during 1974 and 1975. Water temperature, pH, Eh, and dissolved O2 were determined on-site. Total alkalinity and F were determined on the day of sample collection. Flame atomic-absorption spectrometry was used to determine concentrations of Li, Na, K, Ca, and Mg. Ultraviolet/visible spectrophotometry was used to determine concentrations of Fe(II), Fe(III), As(III), and As(V). Direct-current plasma-optical-emission spectrometry was used to determine the concentrations of B, Ba, Cd, Cs, Cu, Mn, Ni, Pb, Rb, Sr, and Zn. Two samples collected from Yellowstone Park in June 1974 were used as reference samples for testing the plasma analytical method. Results of these tests demonstrate acceptable precision for all detectable elements. Charge imbalance calculations revealed a small number of samples that may have been subject to measurement errors in pH or alkalinity. These data represent some of the most complete analyses of Yellowstone waters available.
Determination of 99Tc in fresh water using TRU resin by ICP-MS.
Guérin, Nicolas; Riopel, Remi; Kramer-Tremblay, Sheila; de Silva, Nimal; Cornett, Jack; Dai, Xiongxin
2017-10-02
Technetium-99 ( 99 Tc) determination at trace level by inductively coupled plasma mass spectrometry (ICP-MS) is challenging because there is no readily available appropriate Tc isotopic tracer. A new method using Re as a recovery tracer to determine 99 Tc in fresh water samples, which does not require any evaporation step, was developed. Tc(VII) and Re(VII) were pre-concentrated on a small anion exchange resin (AER) cartridge from one litre of water sample. They were then efficiently eluted from the AER using a potassium permanganate (KMnO 4 ) solution. After the reduction of KMnO 4 in 2 M sulfuric acid solution, the sample was passed through a small TRU resin cartridge. Tc(VII) and Re(VII) retained on the TRU resin were eluted using near boiling water, which can be directly used for the ICP-MS measurement. The results for method optimisation, validation and application were reported. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.
Estimating irrigation water demand in the Moroccan Drâa Valley using contingent valuation.
Storm, Hugo; Heckelei, Thomas; Heidecke, Claudia
2011-10-01
Irrigation water management is crucial for agricultural production and livelihood security in Morocco as in many other parts of the world. For the implementation of an effective water management, knowledge about farmers' demand for irrigation water is crucial to assess reactions to water pricing policy, to establish a cost-benefit analysis of water supply investments or to determine the optimal water allocation between different users. Previously used econometric methods providing this information often have prohibitive data requirements. In this paper, the Contingent Valuation Method (CVM) is adjusted to derive a demand function for irrigation water along farmers' willingness to pay for one additional unit of surface water or groundwater. An application in the Middle Drâa Valley in Morocco shows that the method provides reasonable results in an environment with limited data availability. For analysing the censored survey data, the Least Absolute Deviation estimator was found to be a more suitable alternative to the Tobit model as errors are heteroscedastic and non-normally distributed. The adjusted CVM to derive demand functions is especially attractive for water scarce countries under limited data availability. Copyright © 2011 Elsevier Ltd. All rights reserved.
Illinois ground-water observation network; a preliminary planning document for network design
Frost, L.R.; O'Hearn, Michael; Gibb, J.P.; Sherrill, M.G.
1984-01-01
Water-level and water-quality networks in Illinois were evaluated to determine the adequacy and completeness of available data bases. Ground-water data in present data bases are inadequate to provide information on ground-water quality and water levels in large areas of Illinois and in the major geohydrologic units underlying Illinois and surrounding areas. Data-management needs indicate that a new data base is desirable and could be developed by use of carefully selected available data and new data. Types of data needed to define ground-water quality and water levels in selected geohydrologic units were tentatively identified. They include data on concentrations of organic chemicals related to activities of man, and concentrations of inorganic chemicals which relate either to man 's activities or to the chemical composition of the source aquifer. Water-level data are needed which can be used to describe short- and long-term stresses on the ground-water resources of Illinois. Establishment of priorities for data collection has been deferred until existing hydrologic data files can be stored for usable data and until input from other local, State, and Federal agencies can be solicited and compiled. (USGS)
Densmore, Jill N.
2003-01-01
Ground-water pumping in the Irwin Basin at Fort Irwin National Training Center, California resulted in water-level declines of about 30 feet from 1941 to 1996. Since 1992, artificial recharge from wastewater-effluent infiltration and irrigation-return flow has stabilized water levels, but there is concern that future water demands associated with expansion of the base may cause a resumption of water-level declines. To address these concerns, a ground-water flow model of the Irwin Basin was developed to help better understand the aquifer system, assess the long-term availability and quality of ground water, and evaluate ground-water conditions owing to current pumping and to plan for future water needs at the base. Historical data show that ground-water-level declines in the Irwin Basin between 1941 and 1996, caused the formation of a pumping depression near the pumped wells, and that recharge from the wastewater-treatment facility and disposal area caused the formation of a recharge mound. There have been two periods of water-level recovery in the Irwin Basin since the development of ground water in this basin; these periods coincide with a period of decreased pumpage from the basin and a period of increased recharge of water imported from the Bicycle Basin beginning in 1967 and from the Langford Basin beginning in 1992. Since 1992, artificial recharge has exceeded pumpage in the Irwin Basin and has stabilized water-level declines. A two-layer ground-water flow model was developed to help better understand the aquifer system, assess the long-term availability and quality of ground water, and evaluate ground-water conditions owing to current pumping and to plan for future water needs at the base. Boundary conditions, hydraulic conductivity, altitude of the bottom of the layers, vertical conductance, storage coefficient, recharge, and discharge were determined using existing geohydrologic data. Rates and distribution of recharge and discharge were determined from existing data and estimated when unavailable. Results of predictive simulations indicate that in 50 years, if artificial recharge continues to exceed pumpage in Irwin Basin, water levels could rise as much as 65 feet beneath the pumping depression, and as much as 10 feet in the wastewater-treatment facility and disposal area. Particle-tracking simulations were used to determine the pathlines and the traveltimes of water high in dissolved solids into the main pumping area. The pathlines of particles from two areas with high dissolved-solids concentrations show that in 50 years water from these areas almost reaches the nearest pumped well.
Hard water softening effect of a baby cleanser
Walters, Russel M; Anim-Danso, Emmanuel; Amato, Stephanie M; Capone, Kimberly A; Mack, M Catherine; Telofski, Lorena S; Mays, David A
2016-01-01
Background Hard water is associated with atopic dermatitis (eczema). We wanted to determine if a baby cleanser and its individual components altered free ionized calcium (Ca2+) in a simulated hard water baby bath. For these studies, an in vitro determination of free Ca2+ in a simulated hard water baby bath, and an in vivo exploratory study of free Ca2+ absorption into skin from hard water were performed. Methods Free Ca2+ was measured with an ion-sensitive electrode in vitro in hard water (100–500 ppm, Ca2+) before and after addition of the cleanser and/or its components. In an exploratory study, absorption of Ca2+ into skin from hard water was determined in three female participants (aged 21–29 years). Results At an in-use dilution of 1%, the test cleanser reduced free Ca2+ from ~500 ppm to <200 ppm; a 10% in-use dilution bound virtually all free Ca2+. The anionic surfactant component contributed the most to this effect. In the exploratory in vivo study, we measured a reduction of ~15% in free Ca2+ from simulated hard water over 10 minutes. Conclusion Baby cleansers can bind free Ca2+ and reduce the effective water hardness of bath water. Reducing the amount of free Ca2+ in the water will reduce the availability of the ion for binding to the skin. Altering or reducing free Ca2+ concentrations in bath water may be an important parameter in creating the ideal baby bath. PMID:27789967
Teschoviruses as Indicators of Porcine Fecal Contamination of Surface Water
Jiménez-Clavero, Miguel Angel; Fernández, Carlos; Ortiz, José Antonio; Pro, Javier; Carbonell, Gregoria; Tarazona, José Vicente; Roblas, Neftalí; Ley, Victoria
2003-01-01
Teschoviruses specifically infect pigs and are shed in pig feces. Hence, their presence in water should indicate contamination with pig fecal residues. To assess this hypothesis, we have developed a real-time reverse transcriptase PCR (RT-PCR) method that allows the quantitative detection of pig teschovirus (PTV) RNA. The method is able to detect 92 fg of PTV RNA per ml of sample. Using this method, we have detected the presence of PTV RNA in water and fecal samples from all pig farms examined (n = 5). Feces from other animal species (cattle, sheep, and goats) were negative in this test. To compare the PTV RNA detection method with conventional chemical determinations currently in use for evaluation of water contamination, we analyzed water samples collected downstream from a pig slurry spillage site. We have found a positive correlation within both types of determinations. The sensitivity of the PTV detection assay was similar to that achieved by unspecific organic matter determination and superior to all other conventional chemical analyses performed. Furthermore, the new method is highly specific, revealing the porcine origin of the contamination, a feature that is lacking in currently available methods for the assessment of water contamination. PMID:14532098
In-Package Chemistry Abstraction
DOE Office of Scientific and Technical Information (OSTI.GOV)
E. Thomas
2004-11-09
This report was developed in accordance with the requirements in ''Technical Work Plan for: Regulatory Integration Modeling and Analysis of the Waste Form and Waste Package'' (BSC 2004 [DIRS 171583]). The purpose of the in-package chemistry model is to predict the bulk chemistry inside of a breached waste package and to provide simplified expressions of that chemistry as function of time after breach to Total Systems Performance Assessment for the License Application (TSPA-LA). The scope of this report is to describe the development and validation of the in-package chemistry model. The in-package model is a combination of two models, amore » batch reactor model that uses the EQ3/6 geochemistry-modeling tool, and a surface complexation model that is applied to the results of the batch reactor model. The batch reactor model considers chemical interactions of water with the waste package materials and the waste form for commercial spent nuclear fuel (CSNF) waste packages and codisposed waste packages that contain both high-level waste glass (HLWG) and DOE spent fuel. The surface complexation model includes the impact of fluid-surface interactions (i.e., surface complexation) on the resulting fluid composition. The model examines two types of water influx: (1) the condensation of water vapor that diffuses into the waste package, and (2) seepage water that enters the waste package from the drift as a liquid. (1) Vapor Influx Case: The condensation of vapor onto the waste package internals is simulated as pure H2O and enters at a rate determined by the water vapor pressure for representative temperature and relative humidity conditions. (2) Water Influx Case: The water entering a waste package from the drift is simulated as typical groundwater and enters at a rate determined by the amount of seepage available to flow through openings in a breached waste package. TSPA-LA uses the vapor influx case for the nominal scenario for simulations where the waste package has been breached but the drip shield remains intact, so all of the seepage flow is diverted from the waste package. The chemistry from the vapor influx case is used to determine the stability of colloids and the solubility of radionuclides available for transport by diffusion, and to determine the degradation rates for the waste forms. TSPA-LA uses the water influx case for the seismic scenario, where the waste package has been breached and the drip shield has been damaged such that seepage flow is actually directed into the waste package. The chemistry from the water influx case that is a function of the flow rate is used to determine the stability of colloids and the solubility of radionuclides available for transport by diffusion and advection, and to determine the degradation rates for the CSNF and HLW glass. TSPA-LA does not use this model for the igneous scenario. Outputs from the in-package chemistry model implemented inside TSPA-LA include pH, ionic strength, and total carbonate concentration. These inputs to TSPA-LA will be linked to the following principle factors: dissolution rates of the CSNF and HLWG, dissolved concentrations of radionuclides, and colloid generation.« less
Stomatal sensitivity to vapour pressure deficit relates to climate of origin in Eucalyptus species.
Bourne, Aimee E; Haigh, Anthony M; Ellsworth, David S
2015-03-01
Selecting plantation species to balance water use and production requires accurate models for predicting how species will tolerate and respond to environmental conditions. Although interspecific variation in water use occurs, species-specific parameters are rarely incorporated into physiologically based models because often the appropriate species parameters are lacking. To determine the physiological control over water use in Eucalyptus, five stands of Eucalyptus species growing in a common garden were measured for sap flux rates and their stomatal response to vapour pressure deficit (D) was assessed. Maximal canopy conductance and whole-canopy stomatal sensitivity to D and reduced water availability were lower in species originating from more arid climates of origin than those from humid climates. Species from humid climates showed a larger decline in maximal sap flux density (JSmax) with reduced water availability, and a lower D at which stomatal closure occurred than species from more arid climates, implying larger sensitivity to water availability and D in these species. We observed significant (P < 0.05) correlations of species climate of origin with mean vessel diameter (R(2) = 0.90), stomatal sensitivity to D (R(2) = 0.83) and the size of the decline in JSmax to restricted water availability (R(2) = 0.94). Thus aridity of climate of origin appears to have a selective role in constraining water-use response among the five Eucalyptus plantation species. These relationships emphasize that within this congeneric group of species, climate aridity constrains water use. These relationships have implications for species choices for tree plantation success against drought-induced losses and the ability to manage Eucalyptus plantations against projected changes in water availability and evaporation in the future. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
NASA Astrophysics Data System (ADS)
Joshi, Nitesh; Romanias, Manolis N.; Riffault, Veronique; Thevenet, Frederic
2017-08-01
The adsorption of water molecules on natural mineral dusts was investigated employing in situ Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS). The natural dust samples originated from North and West Africa, Saudi Arabia and Gobi desert regions. Furthermore, the hygroscopicity of commercially available Arizona Test Dusts (ATDs) and Icelandic volcanic ash were examined. N2 sorption measurements, X-ray fluorescence and diffraction (XRF and XRD), as well as Inductively Coupled Plasma Mass Spectrometry (ICP-MS) analyses were performed to determine the physicochemical properties of the particles. The water adsorption experiments were conducted in an optical cell, at room temperature under the relative humidity (RH) range of 1.9-95%. Results were simulated using a modified three-parameter Brunauer-Emmett-Teller (BET) equation. Water monolayer (ML) was formed in the RH range of 15-25%, while additional water layers were formed at higher RH. Besides, the standard adsorption enthalpies of water onto natural mineral dust samples were determined. A thorough comparison of two commercially available ATD samples indicated that size distribution and/or porosity should play a key role in particle hygroscopicity. Regarding the natural mineral particles, Ca/Si ratios, and to a lesser extent Al/Si, Na/Si, Mg/Si ratios, were found to impact the minimum RH level required for water monolayer formation. These results suggest that the hygroscopic properties of investigated African dusts are quite similar over the whole investigated RH range. Furthermore, one of the major conclusions is that under most atmospheric relative humidity conditions, natural mineral samples are always covered with at least one layer of adsorbed water.
NASA Astrophysics Data System (ADS)
Khedun, C. P.; Mishra, A. K.; Giardino, J. R.; Singh, V. P.
2011-12-01
Hydrometeorological conditions, and therefore water availability, is affected by large-scale circulation indices. In the Rio Grande, which is a transboundary basin shared between the United States and Mexico, the Pacific Decadal Oscillation (PDO) and El Niño Southern Oscillation (ENSO) influence local hydrological conditions. Different sub-regions of the basin exhibit varying degrees of correlation, but in general, an increase (decrease) in runoff during El Niños (La Niñas) is noted. Positive PDO enhances the effect of El Niño and dampens the negative effect of La Niña, and when it is in its neutral/transition phase, La Niña dominates climatic conditions and reduces water availability. Further, lags of up to 3 months have been found between ENSO and precipitation in the basin. We hypothesize that (1) a trivariate statistical relationship can be established between the two climate indices and water availability, and (2) the relationship can be used to predict water availability based on projected PDO and ENSO conditions. We use copula to establish the dependence between climate indices and water availability. Water availability is generated from Noah land surface model (LSM), forced with the North American Land Data Assimilation System Phase 2 (NLDAS-2). The model is run within NASA GSFC's Land Information System. LSM generated runoff gives a more realistic picture of available surface water as it is not affected by anthropogenic changes, such as the construction of dams, diversions, and other land use land cover changes, which may obscure climatic influences. Marginals from climate indices and runoff are from different distribution families, thus conventional functional forms of multivariate frequency distributions cannot be employed. Copulas offer a viable alternative as marginals from different families can be combined into a joint distribution. Uncertainties in the statistical relationship can be determined and the statistical model can be used for prediction purposes. The outcome of the study can provide advanced warning on the expected state of surface water, based on projected ENSO and PDO conditions. Such warning may help trigger drought management plans in both the US and Mexico for example, and ensure the long-term sustainable management of water in the basin.
NASA Astrophysics Data System (ADS)
Zhou, Xiaohai; Zhou, Jian; Kinzelbach, Wolfgang; Stauffer, Fritz
2014-12-01
The freezing temperature of water in soil is not constant but varies over a range determined by soil texture. Consequently, the amounts of unfrozen water and ice change with temperature in frozen soil, which in turn affects hydraulic, thermal, and mechanical properties of frozen soil. In this paper, an Am-241 gamma ray source and time-domain reflectometry (TDR) were combined to measure unfrozen water content and ice content in frozen soil simultaneously. The gamma ray attenuation was used to determine total water content. The TDR was used to determine the dielectric constant of the frozen soil. Based on a four-phase mixing model, the amount of unfrozen water content in the frozen soil could be determined. The ice content was inferred by the difference between total water content and unfrozen water content. The gamma ray attenuation and the TDR were both calibrated by a gravimetric method. Water contents measured by gamma ray attenuation and TDR in an unfrozen silt column under infiltration were compared and showed that the two methods have the same accuracy and response to changes of water content. Unidirectional column freezing experiments were performed to apply the combined method of gamma ray attenuation and TDR for measuring unfrozen water content and ice content. The measurement error of the gamma ray attenuation and TDR was around 0.02 and 0.01 m3/m3, respectively. The overestimation of unfrozen water in frozen soil by TDR alone was quantified and found to depend on the amount of ice content. The higher the ice content, the larger the overestimation. The study confirmed that the combined method could accurately determine unfrozen water content and ice content in frozen soil. The results of soil column freezing experiments indicate that total water content distribution is affected by available pore space and the freezing front advance rate. It was found that there is similarity between the soil water characteristic and the soil freezing characteristic of variably saturated soil. Unfrozen water content is independent of total water content and affected only by temperature when the freezing point is reached.
Water availability and vulnerability of 225 large cities in the United States
NASA Astrophysics Data System (ADS)
Padowski, Julie C.; Jawitz, James W.
2012-12-01
This study presents a quantitative national assessment of urban water availability and vulnerability for 225 U.S. cities with population greater than 100,000. Here, the urban assessments account for not only renewable water flows, but also the extracted, imported, and stored water that urban systems access through constructed infrastructure. These sources represent important hydraulic components of the urban water supply, yet are typically excluded from water scarcity assessments. Results from this hydraulic-based assessment were compared to those obtained using a more conventional method that estimates scarcity solely based on local renewable flows. The inclusion of hydraulic components increased the mean availability to cities, leading to a significantly lower portion of the total U.S. population considered "at risk" for water scarcity (17%) than that obtained from the runoff method (47%). Water vulnerability was determined based on low-flow conditions, and smaller differences were found for this metric between at-risk populations using the runoff (66%) and hydraulic-based (54%) methods. The large increase in the susceptible population between the scarcity measures evaluated using the hydraulic method may better reconcile the seeming contradiction in the United States between perceptions of natural water abundance and widespread water scarcity. Additionally, urban vulnerability measures developed here were validated using a media text analysis. Vulnerability assessments that included hydraulic components were found to correlate with the frequency of urban water scarcity reports in the popular press while runoff-based measures showed no significant correlation, suggesting that hydraulic-based assessments provide better context for understanding the nature and severity of urban water scarcity issues.
Scherer, Laura; Venkatesh, Aranya; Karuppiah, Ramkumar; Pfister, Stephan
2015-04-21
Physical water scarcities can be described by water stress indices. These are often determined at an annual scale and a watershed level; however, such scales mask seasonal fluctuations and spatial heterogeneity within a watershed. In order to account for this level of detail, first and foremost, water availability estimates must be improved and refined. State-of-the-art global hydrological models such as WaterGAP and UNH/GRDC have previously been unable to reliably reflect water availability at the subbasin scale. In this study, the Soil and Water Assessment Tool (SWAT) was tested as an alternative to global models, using the case study of the Mississippi watershed. While SWAT clearly outperformed the global models at the scale of a large watershed, it was judged to be unsuitable for global scale simulations due to the high calibration efforts required. The results obtained in this study show that global assessments miss out on key aspects related to upstream/downstream relations and monthly fluctuations, which are important both for the characterization of water scarcity in the Mississippi watershed and for water footprints. Especially in arid regions, where scarcity is high, these models provide unsatisfying results.
Determination of the Water Potential Threshold at Which Rice Growth Is Impacted.
Dos Santos, Caio Luiz; de Borja Reis, André Froes; Mazzafera, Paulo; Favarin, José Laércio
2018-06-22
Rice feeds 50% of the world’s population. Flooding is the most common irrigation system used for growing rice, a practice responsible for a large amount of water loss. Climate changes may affect water availability in irrigated agriculture, and it will be necessary to develop more sustainable irrigation practices. The aim of this work was to determine, in controlled conditions, the threshold when water potential begins to decrease plant growth. Two independent greenhouse experiments were conducted during middle summer and fall, in order to validate the results for high and low evapotranspiration conditions. Rice plants were grown in hydroponics and the water potential was adjusted with polyethylene glycol 6000, varying from −0.04 MPa (control) to −0.19 MPa. Leaf water potential, water use efficiency, leaf area, and root and shoot biomass were evaluated. All assayed parameters decreased as the water potential was decreased. The water potential threshold which starts to negatively affect rice growth was between −0.046 and −0.056 MPa, which are values close to those observed in the field in previous research. The definition of a critical value may help to improve water management in rice cultivation and to maintain productivity.
Brenes-Arguedas, T; Roddy, A B; Coley, P D; Kursar, Thomas A
2011-06-01
In tropical forests, regional differences in annual rainfall correlate with differences in plant species composition. Although water availability is clearly one factor determining species distribution, other environmental variables that covary with rainfall may contribute to distributions. One such variable is light availability in the understory, which decreases towards wetter forests due to differences in canopy density and phenology. We established common garden experiments in three sites along a rainfall gradient across the Isthmus of Panama in order to measure the differences in understory light availability, and to evaluate their influence on the performance of 24 shade-tolerant species with contrasting distributions. Within sites, the effect of understory light availability on species performance depended strongly on water availability. When water was not limiting, either naturally in the wetter site or through water supplementation in drier sites, seedling performance improved at higher light. In contrast, when water was limiting at the drier sites, seedling performance was reduced at higher light, presumably due to an increase in water stress that affected mostly wet-distribution species. Although wetter forest understories were on average darker, wet-distribution species were not more shade-tolerant than dry-distribution species. Instead, wet-distribution species had higher absolute growth rates and, when water was not limiting, were better able to take advantage of small increases in light than dry-distribution species. Our results suggest that in wet forests the ability to grow fast during temporary increases in light may be a key trait for successful recruitment. The slower growth rates of the dry-distribution species, possibly due to trade-offs associated with greater drought tolerance, may exclude these species from wetter forests.
Federal policy documentation and geothermal water consumption: Policy gaps and needs
DOE Office of Scientific and Technical Information (OSTI.GOV)
Schroeder, J. N.; Harto, C. B.; Clark, C. E.
With U.S. geothermal power production expected to more than triple by 2040, and the majority of this growth expected to occur in arid and water-constrained areas, it is imperative that decision-makers understand the potential long-term limitations to and tradeoffs of geothermal development due to water availability. To this end, water consumption data, including documentation triggered by the National Environmental Policy Act (NEPA) of 1969, production and injection data, and water permit data, were collected from state and federal environmental policy sources in an effort to determine water consumption across the lifecycle of geothermal power plants. Values extracted from these sourcesmore » were analyzed to estimate water usage during well drilling; to identify sourcing of water for well drilling, well stimulation, and plant operations; and to estimate operational water usage at the plant level. Nevada data were also compared on a facility-by-facility basis with other publicly available water consumption data, to create a complete picture of water usage and consumption at these facilities. This analysis represents a unique method of capturing project-level water data for geothermal projects; however, a lack of statutory and legal requirements for such data and data quality result in significant data gaps, which are also explored« less
Freshwater availability and water fetching distance affect child health in sub-Saharan Africa.
Pickering, Amy J; Davis, Jennifer
2012-02-21
Currently, more than two-thirds of the population in Africa must leave their home to fetch water for drinking and domestic use. The time burden of water fetching has been suggested to influence the volume of water collected by households as well as time spent on income generating activities and child care. However, little is known about the potential health benefits of reducing water fetching distances. Data from almost 200, 000 Demographic and Health Surveys carried out in 26 countries were used to assess the relationship between household walk time to water source and child health outcomes. To estimate the causal effect of decreased water fetching time on health, geographic variation in freshwater availability was employed as an instrumental variable for one-way walk time to water source in a two-stage regression model. Time spent walking to a household's main water source was found to be a significant determinant of under-five child health. A 15-min decrease in one-way walk time to water source is associated with a 41% average relative reduction in diarrhea prevalence, improved anthropometric indicators of child nutritional status, and a 11% relative reduction in under-five child mortality. These results suggest that reducing the time cost of fetching water should be a priority for water infrastructure investments in Africa.
Variable availability of the purified dihydrochloride salt of 3,3'-dimethoxybenzidine (DMB, ortho-dianisidine) led us to investigate the effects of reagent purity on the analytical results obtinaed when this reagent is used in the photometric determination of the disinfection byp...
Martinez, M.I.; Troester, Joseph W.; Richards, Ronald T.
1995-01-01
Ground-water flow in the coastal plain appears to be radial from the center of the freshwater mound. At the intersection between the coastal plain and the plateau, the flow is parallel to the coastline. The direction of flow on the rest of the plateau could not be determined accurately with the available data.
Modeling sediment transport from an off-road vehicle trail stream crossing using WEPP model
Renee' D. Ayala; Puneet Srivastava; Christian J. Brodbeck; Emily A. Carter; Timothy P. McDonald
2005-01-01
There is a limited information available pertaining to the adverse effects of Off-Road-Vehicle (ORV) use and trail impacts. As a result, this study was initiated in 2003 to (a) quantify water quality impacts of an ORV trail stream crossing through monitoring of total suspended solids, and (b) conduct WEPP (Water Erosion Prediction Project) simulations to determine long...
NASA Astrophysics Data System (ADS)
Mascarenhas, V. J.; Voß, D.; Wollschlaeger, J.; Zielinski, O.
2017-05-01
Optically active constituents (OACs) in addition to water molecules attenuate light via processes of absorption and scattering and thereby determine underwater light availability. An analysis of their optical properties helps in determining the contribution of each of these to light attenuation. With an aim to study the bio-optical variability, absorption budget and 1% spectral light availability, hydrographical (temperature and salinity), and hyperspectral optical (downwelling irradiance and upwelling radiance) profiles were measured along fjord transects in Sognefjord and Trondheimsfjord, Norway. Optical water quality observations were also performed using Secchi disc and Forel-Ule scale. In concurrence, water samples were collected and analyzed via visible spectrophotometry, fluorometry, and gravimetry to quantify and derive inherent optical properties of the water constituents. An absorption model (R2 = 0.91, n = 36, p < 0.05) as a function of OACs is developed for Sognefjord using multiple regression analysis. Influenced by glacial meltwater, Sognefjord had higher concentration of inorganic suspended matter, while Trondheimsfjord had higher concentrations of CDOM. Increase in turbidity caused increased attenuation of light upstream, as a result of which the euphotic depth decreased from outer to inner fjord sections. Triangular representation of absorption budget revealed dominant absorption by CDOM at 443-555 nm, while that by phytoplankton at 665 nm. Sognefjord however exhibited much greater optical complexity. A significantly strong correlation between salinity and acdom440 is used to develop an algorithm to estimate acdom440 using salinity in Trondheimsfjord.
Level of Fluoride in Soil, Grain and Water in Jalgaon District, Maharashtra, India.
Naik, Rahul Gaybarao; Dodamani, Arun Suresh; Vishwakarma, Prashanth; Jadhav, Harish Chaitram; Khairnar, Mahesh Ravindra; Deshmukh, Manjiri Abhay; Wadgave, Umesh
2017-02-01
Fluoride has an influence on both oral as well as systemic health. The major source of fluoride to body is through drinking water as well as through diet. Staple diet mainly depends on local environmental factors, food grains grown locally, its availability etc. Determination of fluoride level in these food grains is important. So, estimation of the amount of fluoride in grains and its relation to the sources of fluoride used for their cultivation viz., soil and water is important. To estimate the relation of fluoride concentration in grains (Jowar) with respect to that of soil and water used for their cultivation. Fifteen samples each of soil, water and grains were collected using standardized method from the same farm fields of randomly selected villages of Jalgaon district. Fluoride ion concentration was determined in laboratory using SPADNS technique. Mean difference in fluoride levels in between the groups were analyzed using ANOVA and Post-Hoc Tukey test. Linear regression method was applied to analyse the association of the fluoride content of grain with water and soil. There was a significant difference in between mean fluoride levels of soil and water (p<0.001) and in between soil and grain (p<0.001); however, difference in between mean fluoride levels of water and grain was found to be non significant (p=0.591). Also fluoride levels in all the three groups showed significant association with each other. Fluoride level of soil, grains and water should be adjusted to an optimum level. Soil has positive correlation with respect to uptake of fluoride by Jowar grains. So, Jowar grains with optimum fluoride content should be made available in the commercial markets so that oral and general health can be benefitted.
Risch, M.R.; Robinson, B.A.
2001-01-01
Two surface surveys of terrain electromagnetic conductivity were used to map the horizontal extent of the saltwater plume in areas without monitoring wells. Background values of terrain conductivity were measured in an area where water-quality and borehole geophysical data did not indicate saline or brackish water. Based on a guideline from previous case studies, the boundaries of the saltwater plume were mapped where terrain conductivity was 1.5 times background. The extent of the saltwater plume, based on terrain conductivity, generally was consistent with the available water-quality and borehole electromagnetic-conductivity data and with directions of ground-water flow determined from water-level altitudes.
Giles, T.F.
1980-01-01
Hydrologic data was collected in the Gunnison-Crested Butte area , Colo., to determine the availability and chemical quality of groundwater. Parts of the area have undergone rapid population growth in recent years due to an increase of winter sports activities. This rapid growth has resulted in a demand for additional domestic, recreational, and municipal water supplies. Maximum yields of 100 gallons per minute are available from wells completed in the alluvial aquifers while as much as 60 gallons per minute may be obtained from wells completed in the Dakota and Entrada Sandstones. Yields from other aquifers generally are less than 25 gallons per minute. Calcium magnesium bicarbonate water is the predominant water type in the study area. Dissolved solids concentrations ranged from 30 to 829 milligrams per liter and hardness ranged from 18 to 400 milligrams per liter. (USGS)
Pascual, Miquel; Romero, María-Paz; Rufat, Josep; Villar, Josep M
2015-12-01
Rainfed viticulture, mainly in semi-arid environments, is limited by environmental variability, particularly precipitation and its seasonal distribution, and soil water availability, thus ultimately determining the final quality of grape and wine. Studies on the feasibility of practices such as canopy management to adapt plant growth and yield to soil water availability open up possibilities to preserve wine quality and reinforce the characteristics of the terroir. Principal components analysis was used to identify the relationships between a large set of variables, including soil, plant, canopy management, and wine characteristics. Canopy management was found to have a predominant influence on plant response to soil water by modifying plant water status, changing the amino acid profile in berries and, concomitantly, altering the sensorial attributes of the wine obtained. Grapevine canopy management strategies, such as reiterate shoot trimming to restrict growth during early phases, are effective in adapting plant response to soil water availability. Such strategies affect berry and wine quality, mainly the amino acid profile and sensorial attributes of the wine, without changing yield or grape harvest quality control parameters. Also, in such conditions, nitrogen does not make a significant contribution to grapevine growth or yield or to grape quality. © 2015 Society of Chemical Industry.
Protecting health from metal exposures in drinking water.
Armour, Margaret-Ann
2016-03-01
Drinking water is essential to us as human beings. According to the World Health Organization "The quality of drinking-water is a powerful environmental determinant of health" (http://www.who.int/water_sanitation_health/dwq/en/), but clean drinking water is a precious commodity not always readily available. Surface and ground water are the major sources of drinking water. Both can be contaminated, surface water with bacteria while ground water frequently contains salts of metals that occur naturally or are introduced by human activity. This paper will briefly review the metallic salts found in drinking water in areas around the world, as well as list some of the methods used to reduce or remove them. It will then discuss our research on reducing the risk of pollution of drinking water by removal of metal ions from wastewater.
Illicit drugs and the environment--a review.
Pal, Raktim; Megharaj, Mallavarapu; Kirkbride, K Paul; Naidu, Ravi
2013-10-01
Illicit drugs and their metabolites are the latest group of emerging pollutants. Determination of their concentration in environment (such as water bodies, soil, sediment, air) is an indirect tool to estimate the community level consumption of illicit drug and to evaluate potential ecotoxicological impacts from chronic low level exposure. They enter the wastewater network as unaltered drugs and/or their active metabolites by human excretion after illegal consumption or by accidental or deliberate disposal from clandestine drug laboratories. This article critically reviews the occurrence and concentration levels of illicit drugs and their metabolites in different environmental compartments (e.g., wastewater, surface waters, groundwater, drinking water, and ambient air) and their potential impact on the ecosystem. There is limited published information available on the presence of illicit drugs in the environment, reports are available mainly from European countries, UK, USA, and Canada but there is a lack of information from the remainder of the world. Although the environmental concentrations are not very high, they can potentially impact the human health and ecosystem functioning. Cocaine, morphine, amphetamine, and MDMA have potent pharmacological activities and their presence as complex mixtures in water may cause adverse effect on aquatic organisms and human health. However, there is no current regulation demanding the determination of occurrence of these emerging pollutants in treated wastewater, surface water, drinking water, or atmosphere. Thus, critical investigation on distribution pattern of this new group of emerging contaminant and their potential harmful impact on our environment needs immediate attention. Copyright © 2012. Published by Elsevier B.V.
Kansas ground-water observation-well network, 1985
Dague, B.J.; Stullken, L.E.
1986-01-01
Water level measurements are made in 1,892 selected wells in 73 counties, which currently (1985) comprise the Kansas groundwater observation-well network. These measurements are made on a continuous, monthly, quarterly, or annual basis. Water level measurements have been made in observation wells since 1937 as part of a cooperative program among the Kansas Geological Survey , the Kansas State Board of Agriculture, the city of Wichita, and the U.S. Geological Survey. The objectives of the observation-well cooperative program are: (1) to provide long-term records of water level fluctuations in representative wells, (2) to facilitate the determination of possible water level trends that may indicate future availability of groundwater supplies, (3) to aid in the determination of possible changes in the base flow of streams, and (4) to provide information for use in water-resources research. This report lists for each well in the network the location, the first year of recorded water level measurement, the frequency and number of measurements, the land-surface altitude, hexagon-grid identifiers for wells in the High Plains aquifer, and the principal geologic unit(s) in which the well is completed. (USGS)
Nimiroski, Mark T.; Wild, Emily C.
2005-01-01
The Woonasquatucket River Basin includes 51.0 square miles, and the Moshassuck River Basin includes 23.8 square miles in north-central Rhode Island. The study area comprises these two basins. The two basins border each other with the Moshassuck River Basin to the northeast of the Woonasquatucket River Basin. Seven towns are in the Woonasquatucket River Basin, and six towns are in the Moshassuck River Basin. To determine the water use and availability in the study area, water supply and discharge data were collected for these river basins for the 1995–99 period, and compared to estimated long-term water available. The study area is unique in the State of Rhode Island, because no withdrawals from major public suppliers were made during the study period. Withdrawals were, therefore, limited to self-supplied domestic use, two minor suppliers, and one self-supplied industrial user. Because no metered data were available, the summer water withdrawals were assumed to be the same as the estimates for the rest of the year. Seven major water suppliers distribute an average of 17.564 million gallons per day for use in the study area from sources outside of the study area. The withdrawals from minor water suppliers were 0.017 million gallons per day in the study area, all in the town of Smithfield in the Woonasquatucket River Basin. The remaining withdrawals in the study area were estimated to be 0.731 million gallons per day by self-supplied domestic, commercial, industrial, and agricultural users. Return flows in the study area included self-disposed water and disposal from permitted dischargers, including the Smithfield Sewage Treatment Plant. Return flows accounted for 4.116 million gallons per day in the study area. Most public-disposed water (15.195 million gallons per day) is collected by the Narragansett Bay Commission and is disposed outside of the basin in Narragansett Bay. The PART program, a computerized hydrograph-separation application, was used at one index stream-gaging station to determine water availability based on the 75th, 50th, and 25th percentiles of the total base flow, the base flow minus the 7-day, 10-year flow criteria, and the base flow minus the Aquatic Base Flow criteria. The index station selected was the Branch River at Forestdale, which is close to the study area and has a similar percentage of sand and gravel area. Water availability was estimated on the basis of baseflow contributions from sand and gravel deposits and till deposits at the index station. Flows were computed for June, July, August, and September 1957–2000, and a percentage of the total flow was determined to come from either sand and gravel deposits, or till, by using a regression equation. The base-flow contributions were converted to a flow per unit area at the station for the till and for the sand and gravel deposits and then applied to the deposits in the study area basins. These values were used to estimate the gross yield of base flow, as well as to subtract the two low flows (7-day, 10-year flow, and Aquatic Base Flow criteria). The results from the Branch River stream-gaging station were lowest in August at the 75th, 50th, and 25th percentile for total flow with either flow criteria subtracted. The estimated August gross yield at the 50th percentile from the Woonasquatucket River Basin was 12.94 million gallons per day, and 5.91 million gallons per day from the Moshassuck River Basin.A ratio was calculated that is equal to total withdrawals divided by water availability. Water-availability flow scenarios at the 75th, 50th, and 25th percentiles for the basins, which are based on total water available from base-flow contributions from till and sand and gravel deposits in the basins, were assessed. The ratios were the highest in July for the 50th percentile estimated gross yield minus Aquatic Base Flow (ABF) flow criteria, where withdrawals are close to the available water. Ratios are not presented if the available water is less than the flow criteria. The ratio of withdrawals to the July gross yield at the 50th percentile minus Aquatic Base Flow was 0.796 for the Woonasquatucket and 0.275 for the Moshassuck River Basin. A long-term hydrologic budget was calculated for the period of 1956–2000 for the Woonasquatucket River Basin and the period of 1964–2000 for the Moshassuck River Basin. The water withdrawals and return flows used in the budget were from 1995 through 1999. For the hydrologic budget, inflow was assumed to equal outflow and was about 120 million gallons per day in the Woonasquatucket River Basin and 56 million gallons per day in the Moshassuck River Basin. The estimated inflows from precipitation and water return flow were 97.3 and 2.7 percent, respectively, in the Woonasquatucket River Basin, and 98.3 and 1.7 percent, respectively, in the Moshassuck River Basin. The estimated outflows from evapotranspiration, streamflow, and water withdrawals were 43.4, 56.1, and 0.5 percent, respectively, in the Woonasquatucket River Basin, and 49.8, 50, and 0.2 percent, respectively, in the Moshassuck River Basin.
Mapping groundwater availability and adequacy in the Lower Zambezi River basin
NASA Astrophysics Data System (ADS)
Pérez-Lapeña, Blanca; Saimone, Francisco; Juizo, Dinis
2018-05-01
Groundwater plays an important role as a source of water for various socio-economic uses and environmental requirements in the lower Zambezi basin in Mozambique. Hence it is important to know its availability and adequacy in space to inform decision making for sustainable water management practices. For a derivation of a Groundwater Availability map and a Groundwater Adequacy map we adapted the DRASTIC methodology in a GIS environment to determine how different parameters, such as precipitation, topography, soil drainage, land use and vegetation cover, aquifer characteristics and groundwater quality affect (i) groundwater recharge on a long-term sustainable basis, (ii) the short-term abstraction potential and (iii) the long-term adequacy of groundwater utilization for domestic use. Results showed that groundwater availability in the Zambezi basin varies mostly from medium to low, with highest potential along the perennial rivers and in the delta where it plays a crucial role in environmental preservation. The southern margin of the Zambezi River shows low groundwater availability and also presents low adequacy for domestic use due to poor groundwater quality. The results from this study will be used in determining the most promising future development pathways and select the most attractive strategic development plans of the Mozambican government for the Lower Zambezi basin.
Nutrient availability at Mer Bleue bog measured by PRSTM probes
NASA Astrophysics Data System (ADS)
Wang, M.; Moore, T. R.; Talbot, J.
2015-12-01
Bogs, covering ~0.7 million km2 in Canada, store a large amount of C and N. As nutrient deficient ecosystems, it's critical to examine the nutrient availabilities and seasonal dynamics. We used Plant Root Simulators (PRSTM) at Mer Bleue bog to provide some baseline data on nutrient availability and its variability. In particular, we focused on ammonium, nitrate, phosphate, calcium, magnesium and potassium, iron, sulphate and aluminum. We placed PRS probes at a depth of 5 - 15 cm in pristine plots and plots with long term N, P and K fertilization for 4 weeks and determined the availability of these nutrients, from spring through to fall. Probes were also placed beneath the water table in hummock and hollow microtopography and along a transect including part of the bog which had been drained through the creation of a ditch 80 years ago. The result showed that there was limited available ammonium, nitrate and phosphate in the bog, the seasonal variation of nutrient availabilities probably due to mineralization, an increase in the availability of some nutrients between different water table depths or as a result of drainage, and the relative availability of nutrients compared to the input from fertilization. We suggest that PRS probes could be a useful tool to examine nutrient availability and dynamics in wetlands, with careful consideration of installing condition, for example, proper exposure period, depth relative to water table etc.
Han, Liang-Feng; Gröning, Manfred; Aggarwal, Pradeep; Helliker, Brent R
2006-01-01
The isotope ratio of atmospheric water vapour is determined by wide-ranging feedback effects from the isotope ratio of water in biological water pools, soil surface horizons, open water bodies and precipitation. Accurate determination of atmospheric water vapour isotope ratios is important for a broad range of research areas from leaf-scale to global-scale isotope studies. In spite of the importance of stable isotopic measurements of atmospheric water vapour, there is a paucity of published data available, largely because of the requirement for liquid nitrogen or dry ice for quantitative trapping of water vapour. We report results from a non-cryogenic method for quantitatively trapping atmospheric water vapour using 3A molecular sieve, although water is removed from the column using standard cryogenic methods. The molecular sieve column was conditioned with water of a known isotope ratio to 'set' the background signature of the molecular sieve. Two separate prototypes were developed, one for large collection volumes (3 mL) and one for small collection volumes (90 microL). Atmospheric water vapour was adsorbed to the column by pulling air through the column for several days to reach the desired final volume. Water was recovered from the column by baking at 250 degrees C in a dry helium or nitrogen air stream and cryogenically trapped. For the large-volume apparatus, the recovered water differed from water that was simultaneously trapped by liquid nitrogen (the experimental control) by 2.6 per thousand with a standard deviation (SD) of 1.5 per thousand for delta(2)H and by 0.3 per thousand with a SD of 0.2 per thousand for delta(18)O. Water-vapour recovery was not satisfactory for the small volume apparatus. Copyright (c) 2006 John Wiley & Sons, Ltd.
BOREAS HYD-1 Soil Hydraulic Properties
NASA Technical Reports Server (NTRS)
Hall, Forrest G. (Editor); Knapp, David E. (Editor); Kelly, Shaun F.; Stangel, David E.; Smith, David E. (Technical Monitor)
2000-01-01
The Boreal Ecosystem-Atmosphere Study (BOREAS) Hydrology (HYD)-1 team coordinated a program of data collection to measure and monitor soil properties in collaboration with other science team measurement needs. This data set contains soil hydraulic properties determined at the Northern Study Area (NSA) and Southern Study Area (SSA) flux tower sites based on analysis of in situ tension infiltrometer tests and laboratory-determined water retention from soil cores collected during the 1994-95 field campaigns. Results from this analysis are saturated hydraulic conductivity, and fitting parameters for the van Genuchten-Mualem soil hydraulic conductivity and water retention function at flux tower sites. The data are contained in tabular ASCII files. The HYD-01 soil hydraulic properties data are available from the Earth Observing System Data and Information System (EOSDIS) Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC). The data files are available on a CD-ROM (see document number 20010000884).
Methods for determination of inorganic substances in water and fluvial sediments
Fishman, Marvin J.; Friedman, Linda C.
1989-01-01
Chapter Al of the laboratory manual contains methods used by the U.S. Geological Survey to analyze samples of water, suspended sediments, and bottom material for their content of inorganic constituents. Included are methods for determining the concentration of dissolved constituents in water, the total recoverable and total of constituents in water-suspended sediment samples, and the recoverable and total concentrations of constituents in samples of bottom material. The introduction to the manual includes essential definitions and a brief discussion of the use of significant figures in calculating and reporting analytical results. Quality control in the water-analysis laboratory is discussed, including the accuracy and precision of analyses, the use of standard-reference water samples, and the operation of an effective quality-assurance program. Methods for sample preparation and pretreatment are given also. A brief discussion of the principles of the analytical techniques involved and their particular application to water and sediment analysis is presented. The analytical methods of these techniques are arranged alphabetically by constituent. For each method, the general topics covered are the application, the principle of the method, the interferences, the apparatus and reagents required, a detailed description of the analytical procedure, reporting results, units and significant figures, and analytical precision data, when available. More than 126 methods are given for the determination of 70 inorganic constituents and physical properties of water, suspended sediment, and bottom material.
Methods for determination of inorganic substances in water and fluvial sediments
Fishman, Marvin J.; Friedman, Linda C.
1985-01-01
Chapter Al of the laboratory manual contains methods used by the Geological Survey to analyze samples of water, suspended sediments, and bottom material for their content of inorganic constituents. Included are methods for determining the concentration of dissolved constituents in water, total recoverable and total of constituents in water-suspended sediment samples, and recoverable and total concentrations of constituents in samples of bottom material. Essential definitions are included in the introduction to the manual, along with a brief discussion of the use of significant figures in calculating and reporting analytical results. Quality control in the water-analysis laboratory is discussed, including accuracy and precision of analyses, the use of standard reference water samples, and the operation of an effective quality assurance program. Methods for sample preparation and pretreatment are given also.A brief discussion of the principles of the analytical techniques involved and their particular application to water and sediment analysis is presented. The analytical methods involving these techniques are arranged alphabetically according to constituent. For each method given, the general topics covered are application, principle of the method, interferences, apparatus and reagents required, a detailed description of the analytical procedure, reporting results, units and significant figures, and analytical precision data, when available. More than 125 methods are given for the determination of 70 different inorganic constituents and physical properties of water, suspended sediment, and bottom material.
Water resources of the Cook Inlet Basin, Alaska
Freethey, Geoffrey W.; Scully, David R.
1980-01-01
Ground-water and surface-water systems of Cook Inlet basin, Alaska, are analyzed. Geologic and topographic features that control the movement and regional availability of ground water are explained and illustrated. Five aquifer systems beneath the most populous areas are described. Estimates of ground-water yield were determined for the region by using ground-water data for the populated areas and by extrapolating known subsurface conditions and interpreting subsurface conditions from surficial features in the other areas. Area maps of generalized geology, Quaternary sediment thickness, and general availability of ground water are shown. Surface-water resources are summarized by describing how basin characteristics affect the discharge in streams. Seasonal trend of streamflow for three types of streams is described. Regression equations for 4 streamflow characteristics (annual, monthly minimum, and maximum discharge) were obtained by using gaging station streamflow characteristics and 10 basin characteristics. In the 24 regression equations presented, drainage area is the most significant basin characteristic, but 5 others are used. Maps of mean annual unit runoff and minimum unit yield for 7 consecutive days with a recurrence interval of 10 years are shown. Historic discharge data at gaging stations is tabulated and representative low-flow and flood-flow frequency curves are shown. (USGS)
NASA Astrophysics Data System (ADS)
Aziz, Edriyana A.; Malek, Marlinda Abdul; Moni, Syazwan N.; Zulkifli, Nabil F.; Hadi, Iqmal H.
2018-03-01
In many parts of the world, freshwater is scarce and overexploited. The purpose of this study is to determine the water footprint of Water Supply Treatment Process (WSTP) at Panching Water Treatment Plant (WTP) as well as to identify the sustainability of the Sg. Kuantan as an intake resource due to the effect of land use development. The total water footprint (WF) will be calculated by using WF accounting manual. The results obtained shows that the water intake resource is still available but it is believed that it will not be able to cope with the increasing WF. The increment of water demand percentage by 1.8% from 2015 to 2016 has increased 11 times higher of the water footprint percentage, 19.9%. This result shows that the water consumption during the water supply treatment process is two times higher than the demand thus it shows the inefficient of the water management
Delin, Geoffrey N.; Risser, Dennis W.
2007-01-01
Increased demands on water resources by a growing population and recent droughts have raised awareness about the adequacy of ground-water resources in humid areas of the United States. The spatial and temporal variability of ground-water recharge are key factors that need to be quantified to determine the sustainability of ground-water resources. Ground-water recharge is defined herein as the entry into the saturated zone of water made available at the water-table surface, together with the associated flow away from the water table within the saturated zone (Freeze and Cherry, 1979). In response to the need for better estimates of ground-water recharge, the Ground-Water Resources Program (GWRP) of the U.S. Geological Survey (USGS) began an initiative in 2003 to estimate ground-water recharge rates in the relatively humid areas of the United States.
NASA Astrophysics Data System (ADS)
Conley, Alan H.; Midgley, Desmond C.
1988-07-01
A resourceful holistic water management strategy has been developed for ensuring equitable provision of adequate quantities of water of satisfactory quality at acceptable risk and affordable cost to a wide international range of competing user groups subject to adverse physical and hydrological factors and under rapidly changing social conditions. Scarce resource allocation strategies, based on scientific studies and supported by modern data processing facilities, focus primarily on supply, demand and quality. Supply management implies creation of the best combination of affordable elements of infrastructure for bulk water supplies from available runoff, groundwater, re-use, imports and unconventional sources, sized to meet determinable requirements with appropriate degrees of assurance, coupled with continuous optimization of system operation. Demand management seeks optimum allocation of available supplies to towns, power generation, industry, mining, agriculture, forestry, recreation and ecology, according to priority criteria determined from scientific, economic and socioeconomic studies. Quality management strategies relate to the control of salination, eutrophication and pollution from both diffuse and point sources. As the combined demands of complex First and Third World societies and economies on the available resources rise, increasing attention has to be paid to finding practical compromises to facilitate handling of conflict between legitimate users having widely divergent interests, aspirations and levels of sophistication. For optimum joint utilization, the central regulating authority is striving to forge a consultative partnership within which to promote, among the widest possible spectrum of users, enlightened understanding of the opportunities and limitations in handling complex international, social, political, legal, economic and financial issues associated with water development. These cannot readily be resolved by the methods of traditional hydrological sciences alone.
To determine the end point of wet granulation by measuring powder energies and thermal properties.
Dave, Rutesh H; Wu, Stephen H; Contractor, Labdhi D
2012-04-01
Wet granulation has been widely used in pharmaceutical industry as a tablet manufacturing process. However, end-point determination of wet granulation process has always remained a challenge. Many traditional methods are available for end-point determination, yet accuracy and reproducibility still remain a challenge. Microcrystalline cellulose, widely used as an excipient in pharmaceutical industry, was granulated using water. Wet mass was passed through sieve # 12 and dried till constant percentage loss on drying was obtained and dried granules were obtained. Wet and dried granules collected were subjected to basic flow energy, specific energy, bulk density, pressure drop, differential scanning calorimetry and effusivity measurements. Analysis of data revealed various stages of granule growth from initial seed formation by adding 200-400 g of water, granule growth was observed by adding 600-800 g of water and over wetting was observed at 1155 g of water. In this work, we have justified our work to properly identify and utilize this technique for practical purpose to correctly identify the end-point determination of microcrystalline cellulose and explain various principles underlying energies associated with powder and thermal measurements.
Daigger, Glen T
2009-08-01
Population growth and improving standards of living, coupled with dramatically increased urbanization, are placing increased pressures on available water resources, necessitating new approaches to urban water management. The tradition linear "take, make, waste" approach to managing water increasingly is proving to be unsustainable, as it is leading to water stress (insufficient water supplies), unsustainable resource (energy and chemicals) consumption, the dispersion of nutrients into the aquatic environment (especially phosphorus), and financially unstable utilities. Different approaches are needed to achieve economic, environmental, and social sustainability. Fortunately, a toolkit consisting of stormwater management/rainwater harvesting, water conservation, water reclamation and reuse, energy management, nutrient recovery, and source separation is available to allow more closed-loop urban water and resource management systems to be developed and implemented. Water conservation and water reclamation and reuse (multiple uses) are becoming commonplace in numerous water-short locations. Decentralization, enabled by new, high-performance treatment technologies and distributed stormwater management/rainwater harvesting, is furthering this transition. Likewise, traditional approaches to residuals management are evolving, as higher levels of energy recovery are desired, and nutrient recovery and reuse is to be enhanced. A variety of factors affect selection of the optimum approach for a particular urban area, including local hydrology, available water supplies, water demands, local energy and nutrient-management situations, existing infrastructure, and utility governance structure. A proper approach to economic analysis is critical to determine the most sustainable solutions. Stove piping (i.e., separate management of drinking, storm, and waste water) within the urban water and resource management profession must be eliminated. Adoption of these new approaches to urban water and resource management can lead to more sustainable solutions, defined as financially stable, using locally sustainable water supplies, energy-neutral, providing responsible nutrient management, and with access to clean water and appropriate sanitation for all.
Wild, Emily C.; Nimiroski, Mark T.
2005-01-01
The South Coastal Drainage Basin includes approximately 59.14 square miles in southern Rhode Island. The basin was divided into three subbasins to assess the water use and availability: the Saugatucket, Point Judith Pond, and the Southwestern Coastal Drainage subbasins. Because there is limited information on the ground-water system in this basin, the water use and availability evaluations for these subbasins were derived from delineated surface-water drainage areas. An assessment was completed to estimate water withdrawals, use, and return flow over a 5-year study period from 1995 through 1999 in the basin. During the study period, one major water supplier in the basin withdrew an average of 0.389 million gallons per day from the sand and gravel deposits. Most of the potable water is imported (about 2.152 million gallons per day) from the adjacent Pawcatuck Basin to the northwest. The estimated water withdrawals from the minor water suppliers, which are all in Charlestown, during the study period were 0.064 million gallons per day. The self-supplied domestic, industrial, commercial, and agricultural withdrawals from the basin were 0.574 million gallons per day. Water use in the basin was 2.874 million gallons per day. The average return flow in the basin was 1.190 million gallons per day, which was entirely from self-disposed water users. In this basin, wastewater from service collection areas was exported (about 1.139 million gallons per day) to the Narragansett Bay Drainage Basin for treatment and discharge. During times of little to no recharge, in the form of precipitation, the surface- and ground-water system flows are from storage primarily in the stratified sand and gravel deposits, although there is flow moving through the till deposits at a slower rate. The ground water discharging to the streams, during times of little to no precipitation, is referred to as base flow. The PART program, a computerized hydrograph-separation application, was used at the selected index stream-gaging station to determine water availability based on the 75th, 50th, and 25th percentiles of the total base flow, the base flow minus the 7-day, 10-year flow criteria, and the base flow minus the Aquatic Base Flow criteria at the index station. The base flow calculated at the selected index station was subdivided into two rates on the basis of the percent contributions from sandand-gravel and till deposits. There has been no long-term collection of surface-water data in this study area and therefore an index stream-gaging station in the Pawcatuck Basin was used for the South Coastal Drainage Basin. The Pawcatuck River at Wood River Junction was chosen as the index station for the South Coastal Drainage Basin because the station is representative of the basin on the basis of the percentage of sand and gravel deposits and the average extent of thickness of the sand and gravel deposits. The baseflow contributions from sand and gravel deposits at the index station were computed for June, July, August, and September, and applied to the percentage of surficial deposits at the index station. The base-flow contributions were converted to a per unit area at the station for the till, and for the sand and gravel deposits and applied to the South Coastal Drainage Basin to determine the water availability. The results from the index station, the Pawcatuck River at Wood River Junction streamgaging station, were lowest for the summer in September. To determine water availability in the South Coastal Drainage Basin, the per unit area of the estimated base flows from sand and gravel deposits and till deposits at the index station was applied to the subbasin areas, and the resultant flows were lowest in September. The base flow at the 75th percentile in the basin was 56.95 million gallons per day in June; 32.78 million gallons per day in July; 30.22 million gallons per day in August; and 23.94 million gallons per day in September. The base flow at the 50th percentile in the basin was 44.59 million gallons per day in June; 25.31 million gallons per day in July; 20.75 million gallons per day in August; and 17.01 million gallons per day in September. The base flow at the 25th percentile in the basin was 35.52 million gallons per day in June; 20.40 million gallons per day in July; 14.94 million gallons per day in August; and 12.00 million gallons per day in September. There are some limitations in the application of this method along the coast, because saltwater intrusion can change the amount of fresh ground-water discharge to the coastal saltwater ecosystem. A ground-water system analysis evaluating these variances would provide additional information to assess the water availability along the coast. Because water withdrawals and use are greater during the summer than other times of the year, water availability in June, July, August, and September was assessed and compared to water withdrawals in the basin. The ratios were calculated by dividing the water withdrawals by the water-availability flow scenarios at the 75th, 50th, and 25th percentiles for the basin, which are based on total water available from base-flow contributions from till and sand and gravel deposits in the basin. The closer the ratio is to one, the closer the withdrawals are to the estimated water available, and the net water available decreases. For the study period, the withdrawals in July were higher than the other summer months. The ratios in the basin for the base-flow scenario, with no low-flow criteria removed, ranged from 0.029 to 0.046 in June; 0.059 to 0.094 in July; 0.050 to 0.100 in August; and 0.040 to 0.079 in September. A long-term hydrologic budget (60 years) was calculated for the South Coastal Drainage Basin to identify and assess the basin and subbasin inflow and outflows. This coastal basin is different than other study areas because all three of the subbasins drain into salt water, Point Judith Point, Long Island Sound, and Rhode Island Sound towards the Atlantic Ocean, or internally within the subbasin to the salt ponds. The hydrologic budgets, therefore, were compiled by subbasin. The basin hydrologic budget is the sum of the three subbasin budgets. Unlike a river subbasin drainage system, however, the estimated streamflows out of the subbasins were also considered outflows from the basin. The water withdrawals and return flows used in the budget were from 1995 through 1999. For the hydrologic budget, it was assumed that inflow equals outflow, where the estimated inflows were from precipitation and wastewater-return flow, and the estimated outflows were from evapotranspiration, streamflow, and water withdrawals.
Nitrate biosensors and biological methods for nitrate determination.
Sohail, Manzar; Adeloju, Samuel B
2016-06-01
The inorganic nitrate (NO3‾) anion is present under a variety of both natural and artificial environmental conditions. Nitrate is ubiquitous within the environment, food, industrial and physiological systems and is mostly present as hydrated anion of a corresponding dissolved salt. Due to the significant environmental and toxicological effects of nitrate, its determination and monitoring in environmental and industrial waters are often necessary. A wide range of analytical techniques are available for nitrate determination in various sample matrices. This review discusses biosensors available for nitrate determination using the enzyme nitrate reductase (NaR). We conclude that nitrate determination using biosensors is an excellent non-toxic alternative to all other available analytical methods. Over the last fifteen years biosensing technology for nitrate analysis has progressed very well, however, there is a need to expedite the development of nitrate biosensors as a suitable alternative to non-enzymatic techniques through the use of different polymers, nanostructures, mediators and strategies to overcome oxygen interference. Copyright © 2016 Elsevier B.V. All rights reserved.
Quantifying human impact on hydrological drought using an Earth System Model
NASA Astrophysics Data System (ADS)
van Huijgevoort, Marjolein; Chaney, Nathaniel; Malyshev, Sergey; Shevliakova, Elena; Milly, Chris
2017-04-01
Predicting the human impact on the present and future hydrological cycle remains a significant scientific challenge. Anthropogenic impact includes water management practices like diverting water for irrigation, abstraction of groundwater, and reservoirs. Hydrological extremes, in particular, are heavily affected by water management practices, due to the existing stress on the system during droughts and floods. Therefore, to prepare adaptation plans for hydrological extremes in the future, it is essential to account for water management and other human influences in Earth System Models. In this study we have implemented water management practices in the state-of-the-art GFDL land model, which includes terrestrial water, energy, and carbon balances. Both irrigation practices and reservoirs have been added in the land surface model component of the model. Irrigation amounts are determined from the soil water balance, the evaporative demand of the vegetation and fractional coverage of croplands. The resulting water demand is fulfilled by abstractions from surface water and groundwater. Reservoir outflow is dynamically coupled to the downstream water demand and available reservoir storage. Retrospective model simulations over the contiguous United States indicate a strong human influence on hydrological drought. A water management attribution analysis shows a significant impact on the water availability, mostly in the Midwest of the United States and California. Implementation of reservoirs alters the flow regime, thereby decreasing the short-term drought impact, however, in the case of multi-year drought, impacts are delayed due to the dependency on the reservoir outflow. Irrigation, on the other hand, decreases the water availability in rivers due to increased evapotranspiration leading to a higher drought impact. The average increase in evapotranspiration amounted up to 2 mm/day for cropland areas in California and Texas. Overall, the results show the importance of including water management in global scale models. This new modelling framework can be used to understand how humans will impact future water availability, water scarcity, and drought. Next steps will include coupled model simulations to investigate the human impact on feedbacks in land-atmosphere interactions.
Jorgensen, Rachael; Arathi, H S
2013-09-01
A plant investing in reproduction partitions resources between flowering and seed production. Under resource limitation, altered allocations may result in floral trait variations, leading to compromised fecundity. Floral longevity and timing of selfing are often the traits most likely to be affected. The duration of corolla retention determines whether fecundity results from outcrossing or by delayed selfing-mediated reproductive assurance. In this study, the role of pollination schedules and soil water availability on floral longevity and seed production is tested in Collinsia heterophylla (Plantaginaceae). Using three different watering regimes and pollination schedules, effects on floral longevity and seed production were studied in this protandrous, flowering annual. The results reveal that soil water status and pollination together influence floral longevity with low soil water and hand-pollinations early in the floral lifespan reducing longevity. However, early pollinations under excess water did not extend longevity, implying that resource surplus does not lengthen the outcrossing period. The results also indicate that pollen receipt, a reliable cue for fecundity, accelerates flower drop. Early corolla abscission under drought stress could potentially exacerbate sexual conflict in this protandrous, hermaphroditic species by ensuring self-pollen paternity and enabling male control of floral longevity. While pollination schedules did not affect fecundity, water stress reduced per-capita seed numbers. Unmanipulated flowers underwent delayed autonomous selfing, producing very few seeds, suggesting that inbreeding depression may limit benefits of selfing. In plants where herkogamy and dichogamy facilitate outcrossing, floral longevity determines reproductive success and mating system. Reduction in longevity under drought suggests a strong environmental effect that could potentially alter the preferred breeding mode in this mixed-mated species. Extrapolating the findings to unpredictable global drought cycles, it is suggested that in addition to reducing yield, water stress may influence the evolutionary trajectory of plant mating system.
Assessing Dryland Ecosystem Services in Xinjiang, Northwest China
NASA Astrophysics Data System (ADS)
Siew, T. F.; Brauman, K. A.; Zuo, L.; Doll, P. M.
2014-12-01
Dryland ecosystems, including grassland, forest, and irrigated cropland, cover about 41% of earth's land area and are inhabited by over two billion people. In drylands, particularly arid and semiarid areas, the production of ecosystem services is primarily constrained by freshwater availability. Often, water allocated to production by one ecosystem or of one ecosystem service negatively impacts other ecosystems or ecosystem services (ESS). The challenge is to determine how much water should be allocated to which ecosystems (natural and manmade) such that multiple ESS are maximized, thus improving overall well-being. This strategic management decision must be supported by knowledge about spatial and temporal availability of water and its relationship to production (location and scale) of ESS that people receive. We assess the spatial and temporal relationships between water availability and ESS production in Xinjiang, Northwest China. We address four questions: (1) What services are produced by which ecosystems with water available? (2) Where are these services produced? (3) Who uses the services produced? (4) How the production of services changes with variability of water available? Using existing global, national, and regional spatial and statistical data, we assess food, fiber, livestock, and wood production as well as unique forest landscapes (as a proxy for aesthetic appreciation and habitats for unique animals and plants) and protection from dust storms. Irrigation is necessary for crop production in Xinjiang. The production of about 4.2 million tons of wheat and 500,000 tons of cotton requires more than 2 km3 of water each year. This is an important source of food and income for local residents, but the diverted water has negative and potentially costly impacts on downstream forests that potentially provide aesthetic services and protection from dust. Our analyses also show that cropland had increased by about 1.6 million ha from 1987 to 2010, while grassland and woodland had decreased by about 1.5 million ha and 33,000 ha, respectively. Cropland expansion had increased water need for irrigation and decreased services produced by other ecosystems. This assessment helps understand connections between water and ESS better and contributes to water and land management in dry regions, particularly China.
Evaluating the potential of improving residential water balance at building scale.
Agudelo-Vera, Claudia M; Keesman, Karel J; Mels, Adriaan R; Rijnaarts, Huub H M
2013-12-15
Earlier results indicated that, for an average household, self-sufficiency in water supply can be achieved by following the Urban harvest Approach (UHA), in a combination of demand minimization, cascading and multi-sourcing. To achieve these results, it was assumed that all available local resources can be harvested. In reality, however, temporal, spatial and location-bound factors pose limitations to this harvest and, thus, to self-sufficiency. This article investigates potential spatial and temporal limitations to harvest local water resources at building level for the Netherlands, with a focus on indoor demand. Two building types were studied, a free standing house (one four-people household) and a mid-rise apartment flat (28 two-person households). To be able to model yearly water balances, daily patterns considering household occupancy and presence of water using appliances were defined per building type. Three strategies were defined. The strategies include demand minimization, light grey water (LGW) recycling, and rainwater harvesting (multi-sourcing). Recycling and multi-sourcing cater for toilet flushing and laundry machine. Results showed that water saving devices may reduce 30% of the conventional demand. Recycling of LGW can supply 100% of second quality water (DQ2) which represents 36% of the conventional demand or up to 20% of the minimized demand. Rainwater harvesting may supply approximately 80% of the minimized demand in case of the apartment flat and 60% in case of the free standing house. To harvest these potentials, different system specifications, related to the household type, are required. Two constraints to recycle and multi-source were identified, namely i) limitations in the grey water production and available rainfall; and ii) the potential to harvest water as determined by the temporal pattern in water availability, water use, and storage and treatment capacities. Copyright © 2013 Elsevier Ltd. All rights reserved.
Analyzing Uncertainty and Risk in the Management of Water Resources in the State Of Texas
NASA Astrophysics Data System (ADS)
Singh, A.; Hauffpauir, R.; Mishra, S.; Lavenue, M.
2010-12-01
The State of Texas updates its state water plan every five years to determine the water demand required to meet its growing population. The plan compiles forecasts of water deficits from state-wide regional water planning groups as well as the water supply strategies to address these deficits. To date, the plan has adopted a deterministic framework, where reference values (e.g., best estimates, worst-case scenario) are used for key factors such as population growth, demand for water, severity of drought, water availability, etc. These key factors can, however, be affected by multiple sources of uncertainties such as - the impact of climate on surface water and groundwater availability, uncertainty in population projections, changes in sectoral composition of the economy, variability in water usage, feasibility of the permitting process, cost of implementation, etc. The objective of this study was to develop a generalized and scalable methodology for addressing uncertainty and risk in water resources management both at the regional and the local water planning level. The study proposes a framework defining the elements of an end-to-end system model that captures the key components of demand, supply and planning modules along with their associated uncertainties. The framework preserves the fundamental elements of the well-established planning process in the State of Texas, promoting an incremental and stakeholder-driven approach to adding different levels of uncertainty (and risk) into the decision-making environment. The uncertainty in the water planning process is broken down into two primary categories: demand uncertainty and supply uncertainty. Uncertainty in Demand is related to the uncertainty in population projections and the per-capita usage rates. Uncertainty in Supply, in turn, is dominated by the uncertainty in future climate conditions. Climate is represented in terms of time series of precipitation, temperature and/or surface evaporation flux for some future time period of interest, which can be obtained as outputs of global climate models (GCMs). These are then linked with hydrologic and water-availability models (WAMs) to estimate water availability for the worst drought conditions under each future climate scenario. Combining the demand scenarios with the water availability scenarios yields multiple scenarios for water shortage (or surplus). Given multiple shortage/surplus scenarios, various water management strategies can be assessed to evaluate the reliability of meeting projected deficits. These reliabilities are then used within a multi-criteria decision-framework to assess trade-offs between various water management objectives, thus helping to make more robust decisions while planning for the water needs of the future.
Water law as an adaptation strategy for global water scarcity in the future
NASA Astrophysics Data System (ADS)
Kakinuma, K.; Yoshikawa, S.; Endo, T.; Kanae, S.
2014-12-01
Water scarcity due to climate changes and growing human population is a major concern for the world. Adaptation and mitigation strategies should be developed for water scarcity in the future. Previous studies assessed the future water availability by hard technology (e.g., reservoirs, reclaimed and desalinated water plants) as adaptation strategies. On the other hand, soft path such as water law and policy would also be important for adaptation strategies. Water transfers is reallocation of water among water users. For example, distribution of the amount of available water is often heterogeneous especially during drought periods. If water transfers are permitted in these areas, water can be moved from surplus areas/sections to critical need areas/sections. There are several studies which describe the water transfer at the local scales (i.e., water bank in California), however the factors that determined the establishment of water transfer are not clear. If we can detect the factors, it could be used to estimate in which areas the water transfer would come into existence. This in turn would reduce the water stress. Here, we focus on historical interaction between human activity and water environments. Generally, rules of water use are developed by repeated discussion among water users. The frequency of these discussions would be related with their land use, frequency of drought and water resource sizes. For example, people in rice crop area need to discuss about water allocation compared to wheat crop area. Therefore, we examine the relationship between the permission of water transfer and factors such as water environment and human activity in the world.
Vibrational excitation of water by electron impact
DOE Office of Scientific and Technical Information (OSTI.GOV)
Khakoo, M. A.; Winstead, C.; McKoy, V.
2009-05-15
Experimental and calculated differential cross sections (DCSs) for electron-impact excitation of the (010) bending mode and unresolved (100) symmetric and (001) antisymmetric stretching modes of water are presented. Measurements are reported at incident energies of 1-100 eV and scattering angles of 10 deg. - 130 deg. and are normalized to the elastic-scattering DCSs for water determined earlier by our group. The calculated cross sections are obtained in the adiabatic approximation from fixed-nuclei, electronically elastic scattering calculations using the Schwinger multichannel method. The present results are compared to available experimental and theoretical data.
The second virial coefficient of system ((nitrogen-water))
NASA Astrophysics Data System (ADS)
Podmurnaya, O. A.
2004-01-01
The virial coefficient data of various components of atmosphere are interesting because permit to evaluate a deviation from ideal gas model. These data may be useful while investigating the clusters generation and determination their contribution in absorption. The second cross virial coefficient Baw for system ((nitrogen water)) has been calculated form +9°C to +50°C using the last experimental data about water vapor mole fraction. The reliability of this coefficient has been tested by analysing of errors sources and by comparing the results with other available experimental data.
Reconstruction of an aquatic food web: Viking Haithabu vs. Medieval Schleswig.
von Steinsdorff, Katja; Grupe, Gisela
2006-09-01
In the last two decades, the analysis of stable isotopes of carbonate and collagen from archaeological bone finds became a useful tool in the reconstruction of ancient food webs. Nevertheless there is still only little information available about aquatic food webs, in particular concerning brackish water ecosystems. The Schlei Fjord in Schleswig-Holstein, Germany, is such an ecosystem and was investigated to determine stable isotopic values for nitrogen, carbon and oxygen from bone collagen and carbonate in archaeological bone finds. Wild birds, mammals and fish bones from the Viking settlement Haithabu and the medieval town of Schleswig have been analyzed in this study to determine stable isotope values for marine and limnic species and to investigate possible isotopic gradients for mixing fresh water and salt water ecosystems.
Garboś, Sławomir; Swiecicka, Dorota
2013-01-01
A method of the classification of natural mineral and spring waters and maximum admissible concentration (MAC) levels of metals present in such types of waters are regulated by Commission Directive 2003/40/EC, Directive 2009/54/EC of the European Parliament and of the Council and Ordinance of Minister of Health of 30 March 2011 on the natural mineral waters, spring waters and potable waters. MAC of barium in natural mineral and spring waters was set at 1.0 mg/l, while World Health Organization determined the Ba guideline value in water intended for human consumption at the level of 0.7 mg/l. The aims of the study were: the determination of barium in natural mineral and spring waters (carbonated, non-carbonated and medium-carbonated waters) produced and bottled on the area of Poland, and assessment of human exposure to this metal presents in the above-mentioned types of waters. The study concerning barium determinations in 23 types of bottled natural mineral waters and 15 types of bottled spring waters (bought in Polish retail outlets) was conducted in 2010. The analyses were performed by validated method of determination of barium in water based on inductively coupled plasma optical emission spectrometry, using modern internal quality control scheme. Concentrations of barium determined in natural mineral and spring waters were in the ranges from 0.0136 mg/l to 1.12 mg/l and from 0.0044 mg/l to 0.43 mg/l, respectively. Only in the single case of natural mineral water the concentration of barium (1.12 mg/l), exceeded above-mentioned MAC for this metal, which is obligatory in Poland and the European Union - 1.0 mg/l. The long-term monitoring of barium concentration in another natural mineral water (2006 - 2010), in which incidental exceeding MAC was observed in 2006, was conducted. All measured barium concentrations in this water were lower than 1.0 mg/l and therefore, it is possible to state that the proper method of mixing waters taken from six independent groundwater intakes applied during production is actually used. The estimated Hazard Quotient indices were in the ranges: 0.0019 - 0.16 (natural mineral waters) and 0.00063 - 0.061 (natural spring waters), respectively. The natural mineral waters are usually characterized by higher Ba concentrations than those observed in the cases of natural spring waters. The presence of a high concentration of HCO3- in such types of natural waters ensures the existence of Ba2+ in solution as Ba(HCO3)2, which is a highly soluble salt. Taking into account the concentrations of barium determined in above-mentioned waters and the available toxicological data for this metal no long-term risk for human health could be expected (estimated Hazard Quotient indices < or = 0.16).
Kıvrak, İbrahim
2015-01-01
Ganoderma adspersum presents a rigid fruiting body owing to chitin content and having a small quantity of water or moisture. The utility of bioactive constituent of the mushroom can only be available by extraction for human usage. In this study, carbohydrate, water-soluble vitamin compositions and amino acid contents were determined in G. adspersum mushroom. The composition in individual sugars was determined by HPLC-RID, mannitol (13.04 g/100 g) and trehalose (10.27 g/100 g) being the most abundant sugars. The examination of water-soluble vitamins and free amino acid composition was determined by UPLC-ESI-MS/MS. Essential amino acid constituted 67.79% of total amino acid, which is well worth the attention with regard to researchers and consumers. In addition, G. adspersum, which is also significantly rich in B group vitamins and vitamin C, can provide a wide range of notable applications in the pharmaceutics, cosmetics, food and dietary supplement industries. G. adspersum revealed its value for pharmacy and nutrition fields.
Howells, Lewis; Longson, M.S.; Hunt, Gilbert L.
1987-01-01
The base of the moderately saline water (water that contains from 3,000 to 10,000 milligrams per liter of dissolved solids) was mapped by using available water-quality data and by determining formation-water resistivities from geophysical well logs based on the resistivity-porosity, spontaneous potential, and resistivity-ratio methods. The contour map developed from these data showed a mound of very saline and briny water, mostly of sodium chloride and sodium bicarbonate type, in most of that part of the Uinta Basin that is underlain by either the Green River or Wasatch Formations. Along its northern edge, the mound rises steeply from below sea level to within 2,000 feet of the land surface and, locally, to land surface. Along its southern edge, the mound rises less steeply and is more complex in outline. This body of very saline to briny water may be a lens; many wells or test holes drilled within the area underlain by the mound re-entered fresh to moderately saline water at depths of 8,000 to 15,000 feet below lam surface.
Flood Map for the Winooski River in Waterbury, Vermont, 2014
Olson, Scott A.
2015-01-01
High-water marks from Tropical Storm Irene were available for seven locations along the study reach. The highwater marks were used to estimate water-surface profiles and discharges resulting from Tropical Storm Irene throughout the study reach. From a comparison of the estimated water-surface profile for Tropical Storm Irene with the water-surface profiles for the 1- and 0.2-percent annual exceedance probability (AEP) floods, it was determined that the high-water elevations resulting from Tropical Storm Irene exceeded the estimated 1-percent AEP flood throughout the Winooski River study reach but did not exceed the estimated 0.2-percent AEP flood at any location within the study reach.
Remotely Sensed Based Lake/Reservoir Routing in Congo River Basin
NASA Astrophysics Data System (ADS)
Raoufi, R.; Beighley, E.; Lee, H.
2017-12-01
Lake and reservoir dynamics can influence local to regional water cycles but are often not well represented in hydrologic models. One challenge that limits their inclusion in models is the need for detailed storage-discharge behavior that can be further complicated in reservoirs where specific operation rules are employed. Here, the Hillslope River Routing (HRR) model is combined with a remotely sensed based Reservoir Routing (RR) method and applied to the Congo River Basin. Given that topographic data are often continuous over the entire terrestrial surface (i.e., does not differentiate between land and open water), the HRR-RR model integrates topographic derived river networks and catchment boundaries (e.g., HydroSHEDs) with water boundary extents (e.g., Global Lakes and Wetlands Database) to develop the computational framework. The catchments bordering lakes and reservoirs are partitioned into water and land portions, where representative flowpath characteristics are determined and vertical water balance and lateral routings is performed separately on each partition based on applicable process models (e.g., open water evaporation vs. evapotranspiration). To enable reservoir routing, remotely sensed water surface elevations and extents are combined to determine the storage change time series. Based on the available time series, representative storage change patterns are determined. Lake/reservoir routing is performed by combining inflows from the HRR-RR model and the representative storage change patterns to determine outflows. In this study, a suite of storage change patterns derived from remotely sensed measurements are determined representative patterns for wet, dry and average conditions. The HRR-RR model dynamically selects and uses the optimal storage change pattern for the routing process based on these hydrologic conditions. The HRR-RR model results are presented to highlight the importance of lake attenuation/routing in the Congo Basin.
Dynamic Heights in the Great Lakes using OPUS Projects
NASA Astrophysics Data System (ADS)
Roman, D. R.; Li, X.
2015-12-01
The U.S. will be implementing new geometric and vertical reference frames in 2022 to replace the North American Datum of 1983 (NAD 83) and the North American Vertical Datum of 1988 (NAVD 88), respectively. Less emphasized is the fact that a new dynamic height datum will also be defined about the same time to replace the International Great Lakes Datum of 1985 (IGLD 85). IGLD 85 was defined concurrent with NAVD 88 and used the same geopotential values. This paper focuses on the use of an existing tool for determining geometric coordinates and a developing geopotential model as a means of determining dynamic heights. The Online Positioning User Service (OPUS) Projects (OP) is an online tool available from the National Geodetic Survey (NGS) for use in developing geometric coordinates from simultaneous observations at multiple sites during multiple occupations. With observations performed at the water level gauges throughout the Great Lakes, the geometric coordinates of the mean water level surface can be determined. NGS has also developed the xGEOID15B model from satellite, airborne and surface gravity data. Using the input geometric coordinates determined through OP, the geopotential values for the water surface at the water level stations around the Great Lakes were determined using the xGEOID15B model. Comparisons were made between water level sites for each Lake as well as to existing IGLD 85 heights. A principal advantage to this approach is the ability to generate new water level control stations using OP, while maintaining the consistency between orthometric and dynamic heights by using the same gravity field model. Such a process may provide a means for determining dynamic heights for a future Great Lakes Datum.
NASA Technical Reports Server (NTRS)
Leonard, J. I.
1977-01-01
The water balance of the Skylab crew was analyzed. Evaporative water loss using a whole body input/output balance equation, water, body tissue, and energy balance was analyzed. The approach utilizes the results of several major Skylab medical experiments. Subsystems were designed for the use of the software necessary for the analysis. A partitional water balance that graphically depicts the changes due to water intake is presented. The energy balance analysis determines the net available energy to the individual crewman during any period. The balances produce a visual description of the total change of a particular body component during the course of the mission. The information is salvaged from metabolic balance data if certain techniques are used to reduce errors inherent in the balance method.
NASA Astrophysics Data System (ADS)
Ferreyra, R.; Stockle, C. O.; Huggins, D. R.
2014-12-01
Soil water storage and dynamics are of critical importance for a variety of processes in terrestrial ecosystems, including agriculture. Many of those systems are under significant pressure in terms of water availability and use. Therefore, assessing alternative scenarios through hydrological models is an increasingly valuable exercise. Soil water holding capacity is defined by the concepts of soil field capacity and plant available water, which are directly related to soil physical properties. Both concepts define the energy status of water in the root system and closely interact with plant physiological processes. Furthermore, these concepts play a key role in the environmental transport of nutrients and pollutants. Soil physical parameters (e.g. saturated hydraulic conductivity, total porosity and water release curve) are required as input for field-scale soil water redistribution models. These parameters are normally not easy to measure or monitor, and estimation through pedotransfer functions is often inadequate. Our objectives are to improve field-scale hydrological modeling by: (1) assessing new undisturbed methodologies for determining important soil physical parameters necessary for model inputs; and (2) evaluating model outputs, making a detailed specification of soil parameters and the particular boundary condition that are driving water movement under two contrasting environments. Soil physical properties (saturated hydraulic conductivity and determination of water release curves) were quantified using undisturbed laboratory methodologies for two different soil textural classes (silt loam and sandy loam) and used to evaluate two soil water redistribution models (finite difference solution and hourly cascade approach). We will report on model corroboration results performed using in situ, continuous, field measurements with soil water content capacitance probes and digital tensiometers. Here, natural drainage and water redistribution were monitored following a controlled water application where the study areas were isolated from other water inputs and outputs. We will also report on the assessment of two soil water sensors (Decagon Devices 5TM capacitance probe and UMS T4 tensiometers) for the two soil textural classes in terms of consistency and replicability.
Finding water scarcity amid abundance using human-natural system models.
Jaeger, William K; Amos, Adell; Bigelow, Daniel P; Chang, Heejun; Conklin, David R; Haggerty, Roy; Langpap, Christian; Moore, Kathleen; Mote, Philip W; Nolin, Anne W; Plantinga, Andrew J; Schwartz, Cynthia L; Tullos, Desiree; Turner, David P
2017-11-07
Water scarcity afflicts societies worldwide. Anticipating water shortages is vital because of water's indispensable role in social-ecological systems. But the challenge is daunting due to heterogeneity, feedbacks, and water's spatial-temporal sequencing throughout such systems. Regional system models with sufficient detail can help address this challenge. In our study, a detailed coupled human-natural system model of one such region identifies how climate change and socioeconomic growth will alter the availability and use of water in coming decades. Results demonstrate how water scarcity varies greatly across small distances and brief time periods, even in basins where water may be relatively abundant overall. Some of these results were unexpected and may appear counterintuitive to some observers. Key determinants of water scarcity are found to be the cost of transporting and storing water, society's institutions that circumscribe human choices, and the opportunity cost of water when alternative uses compete. Published under the PNAS license.
NASA Astrophysics Data System (ADS)
Grafton, R. Quentin; Ward, Michael B.; To, Hang; Kompas, Tom
2011-08-01
Household survey data for 10 countries are used to quantify and test the importance of price and nonprice factors on residential water demand and investigate complementarities between household water-saving behaviors and the average volumetric price of water. Results show (1) the average volumetric price of water is an important predictor of differences in residential consumption in models that include household characteristics, water-saving devices, attitudinal characteristics and environmental concerns as explanatory variables; (2) of all water-saving devices, only a low volume/dual-flush toilet has a statistically significant and negative effect on water consumption; and (3) environmental concerns have a statistically significant effect on some self-reported water-saving behaviors. While price-based approaches are espoused to promote economic efficiency, our findings stress that volumetric water pricing is also one of the most effective policy levers available to regulate household water consumption.
Assessing marginal water values in multipurpose multireservoir systems via stochastic programming
NASA Astrophysics Data System (ADS)
Tilmant, A.; Pinte, D.; Goor, Q.
2008-12-01
The International Conference on Water and the Environment held in Dublin in 1992 emphasized the need to consider water as an economic good. Since water markets are usually absent or ineffective, the value of water cannot be directly derived from market activities but must rather be assessed through shadow prices. Economists have developed various valuation techniques to determine the economic value of water, especially to handle allocation issues involving environmental water uses. Most of the nonmarket valuation studies reported in the literature focus on long-run policy problems, such as permanent (re)allocations of water, and assume that the water availability is given. When dealing with short-run allocation problems, water managers are facing complex spatial and temporal trade-offs and must therefore be able to track site and time changes in water values across different hydrologic conditions, especially in arid and semiarid areas where the availability of water is a limiting and stochastic factor. This paper presents a stochastic programming approach for assessing the statistical distribution of marginal water values in multipurpose multireservoir systems where hydropower generation and irrigation crop production are the main economic activities depending on water. In the absence of a water market, the Lagrange multipliers correspond to shadow prices, and the marginal water values are the Lagrange multipliers associated with the mass balance equations of the reservoirs. The methodology is illustrated with a cascade of hydroelectric-irrigation reservoirs in the Euphrates river basin in Turkey and Syria.
NASA Technical Reports Server (NTRS)
Jones, Robert E.; Morren, W. Earl; Sovey, James S.; Tacina, Robert R.
1987-01-01
Two propulsion systems have been selected for the space station: gaseous H/O rockets for high thrust applications and the multipropellant resistojets for low thrust needs. These two thruster systems integrate very well with the fluid systems on the space station, utilizing waste fluids as their source of propellant. The H/O rocket will be fueled by electrolyzed water and the resistojets will use waste gases collected from the environmental control system and the various laboratories. The results are presented of experimental efforts with H/O and resistojet thrusters to determine their performance and life capability, as well as results of studies to determine the availability of water and waste gases.
Citizen Science: Participatory Monitoring of Water Resources Management in Mustang District, Nepal
NASA Astrophysics Data System (ADS)
Regmi, S.; Bhusal, J.; Gurung, P.; Ochoa-Tocachi, B. F.; Buytaert, W.
2016-12-01
Abstract The Mustang region of the Himalayas has unique geographical and climatic features. This region is characterized by a cold-arid climate with total annual precipitation of less than 300mm. Agriculture and livestock grazing lands are the major ecosystem services, which support directly the livelihoods of local populations yet, are strongly determined by low water availability. As a result, optimizing water resources management is paramount to support local development, but this is severely complicated by the lack of information about water availability. This problem is further aggravated by increasing pressure on the social, physical and climatic environments. In order to support the management of scarce water in irrigation and domestic uses, stream flow and precipitation monitoring networks were established using a participatory approach under the principle of citizen science. Data collection, and the following interpretation and application of the co-generated knowledge relies on local users, whereas the establishment of the system, knowledge co-generation, and development of application tools particularly is part of a collaboration of members of the general public with professional scientists. We show how the resulting data enable local users to quantify the water balance in the area and reduce the uncertainty associated to data-scarcity, which leads to the generation of useable information about water availability for irrigation, livestock grazing, and domestic demand. We contrast the current scenario of water use, under different conditions of natural variability and environmental change, with an optimized water management strategy generated and agreed with local users. This approach contributes to an optimal use of water, to an improvement in ecosystem services supporting to livelihood development and economic progress of local populations. Key words: ecosystem services, climate change, water balance, knowledge generation, irrigation
Implementing the NPDES program: An update on the WET ...
The U.S. EPA has utilized the Clean Water Act - National Pollutant Discharge Elimination System permitting program to protect waters of the U.S for over 40 years. NPDES permit effluent limitations serve as the primary mechanism for controlling discharges of pollutants to receiving waters. When developing effluent limitations for an NPDES permit, a permit writer must consider limits based on both the technology available to control the pollutants (i.e., technology-based effluent limits) and limits that are protective of the water quality standards of the receiving water (i.e., water quality-based effluent limits). WET testing is one of the water quality-based effluent limitation mechanisms available to permit writers that is useful in determining how the additive, synergistic and compounding effects of toxic effluents effect streams. This presentation will provide an overview of the current EPA NPDES permit program direction for increasing the efficacy of NPDES permits program administered by the U.S. EPA and States. The training implementation plan is expected to provide permit writers with a clearer understanding of WET requirements as established via the U.S. EPA WET test manuals, NPDES permitting regulatory authorities, and the WET science which has been long established. not applicable
NASA Astrophysics Data System (ADS)
Knierim, Katherine J.; Nottmeier, Anna M.; Worland, Scott; Westerman, Drew A.; Clark, Brian R.
2017-09-01
Hydrologic budgets to determine groundwater availability are important tools for water-resource managers. One challenging component for developing hydrologic budgets is quantifying water use through time because historical and site-specific water-use data can be sparse or poorly documented. This research developed a groundwater-use record for the Ozark Plateaus aquifer system (central USA) from 1900 to 2010 that related county-level aggregated water-use data to site-specific well locations and aquifer units. A simple population-based linear model, constrained to 0 million liters per day in 1900, provided the best means to extrapolate groundwater-withdrawal rates pre-1950s when there was a paucity of water-use data. To disaggregate county-level data to individual wells across a regional aquifer system, a programmatic hierarchical process was developed, based on the level of confidence that a well pumped groundwater for a specific use during a specific year. Statistical models tested on a subset of the best-available site-specific water-use data provided a mechanism to bracket historic groundwater use, such that groundwater-withdrawal rates ranged, on average, plus or minus 38% from modeled values. Groundwater withdrawn for public supply and domestic use accounted for between 48 and 74% of total groundwater use since 1901, highlighting that groundwater provides an important drinking-water resource. The compilation, analysis, and spatial and temporal extrapolation of water-use data remain a challenging task for water scientists, but is of paramount importance to better quantify groundwater use and availability.
Knierim, Katherine J.; Nottmeier, Anna M.; Worland, Scott C.; Westerman, Drew A.; Clark, Brian R.
2017-01-01
Hydrologic budgets to determine groundwater availability are important tools for water-resource managers. One challenging component for developing hydrologic budgets is quantifying water use through time because historical and site-specific water-use data can be sparse or poorly documented. This research developed a groundwater-use record for the Ozark Plateaus aquifer system (central USA) from 1900 to 2010 that related county-level aggregated water-use data to site-specific well locations and aquifer units. A simple population-based linear model, constrained to 0 million liters per day in 1900, provided the best means to extrapolate groundwater-withdrawal rates pre-1950s when there was a paucity of water-use data. To disaggregate county-level data to individual wells across a regional aquifer system, a programmatic hierarchical process was developed, based on the level of confidence that a well pumped groundwater for a specific use during a specific year. Statistical models tested on a subset of the best-available site-specific water-use data provided a mechanism to bracket historic groundwater use, such that groundwater-withdrawal rates ranged, on average, plus or minus 38% from modeled values. Groundwater withdrawn for public supply and domestic use accounted for between 48 and 74% of total groundwater use since 1901, highlighting that groundwater provides an important drinking-water resource. The compilation, analysis, and spatial and temporal extrapolation of water-use data remain a challenging task for water scientists, but is of paramount importance to better quantify groundwater use and availability.
NASA Technical Reports Server (NTRS)
Ghovanlou, A. H.; Gupta, J. N.; Henderson, R. G.
1977-01-01
The development of quantitative analytical procedures for relating scattered signals, measured by a remote sensor, was considered. The applications of a Monte Carlo simulation model for radiative transfer in turbid water are discussed. The model is designed to calculate the characteristics of the backscattered signal from an illuminated body of water as a function of the turbidity level, and the spectral properties of the suspended particulates. The optical properties of the environmental waters, necessary for model applications, were derived from available experimental data and/or calculated from Mie formalism. Results of applications of the model are presented.
Dugan, Jack T.; Zelt, Ronald B.
2000-01-01
Ground-water recharge and consumptive-irrigation requirements in the Great Plains and adjacent areas largely depend upon an environment extrinsic to the ground-water system. This extrinsic environment, which includes climate, soils, and vegetation, determines the water demands of evapotranspiration, the availability of soil water to meet these demands, and the quantity of soil water remaining for potential ground-water recharge after these demands are met. The geographic extent of the Great Plains contributes to large regional differences among all elements composing the extrinsic environment, particularly the climatic factors. A soil-water simulation program, SWASP, which synthesizes selected climatic, soil, and vegetation factors, was used to simulate the regional soil-water conditions during 1951-80. The output from SWASP consists of several soil-water characteristics, including surface runoff, infiltration, consumptive water requirements, actual evapotranspiration, potential recharge or deep percolation under various conditions, consumptive irrigation requirements, and net fluxes from the ground-water system under irrigated conditions. Simulation results indicate that regional patterns of potential recharge, consumptive irrigation requirements, and net fluxes from the ground-water system under irrigated conditions are largely determined by evapotranspiration and precipitation. The local effects of soils and vegetation on potential recharge cause potential recharge to vary by more than 50 percent in some areas having similar climatic conditions.
A Quick-Test for Biochar Effects on Seed Germination
Biochar is being globally evaluated as a soil amendment to improve soil characteristics (e.g. soil water holding, nutrient exchange, microbiology, pesticides and chemical availability) to increase crop yields. Unfortunately, there are no quick tests to determine what biochar type...
PLUME-SCALER-EVALUATING LONG-TERM MONITORING WELL NETWORKS
EPA's Subsurface Protection and Remediation Division is developing a new computer application called PLUME-SCALER to evaluate long term monitoring well networks using typically available historical site water level data. PLUME-SCALER can be used to determine if there are enough ...
Delerue, Florian; Gonzalez, Maya; Michalet, Richard; Pellerin, Sylvain; Augusto, Laurent
2015-01-01
The identification of an ecological niche specific to the regeneration phase has mobilised significant attention. However, the importance of the regeneration niche concept remains unclear. Our main objective was to study the existence of such a regeneration niche for a leguminous shrub, Ulex europaeus. This study was carried out in southwest France in the context of water and nutrient stresses (mainly phosphorus limitation) due to the presence of nutrient-poor sandy soils. We analysed the regeneration of the species from the germination of seeds and emergence of new seedlings until the seedlings reached young shrub size. Our design included a P fertilisation treatment. We also investigated microsite characteristics (micro-topography and vegetation development) as they can interact with meteorological conditions and determine water availability for seeds and seedlings. We found that P availability controlled seedling growth and the time necessary to reach young shrub size. Water availability appeared to impact the species germination and seedlings survival. We also found that P and water availability depended on the interactions between microsite characteristics and climatic variations. Finally we found evidence that P and water availability are important ecological factors shaping the regeneration niche of the species, but we found weak evidence that any microsite would be appropriate for the regeneration of the species in the long term. Future studies regarding regeneration niches need to distinguish more clearly the ecological factors important for regeneration (the regeneration niche per se) and the physical world where the seedlings appear and develop (the regeneration habitat). PMID:26098877
NASA Astrophysics Data System (ADS)
Tran, Annelise; Goutard, Flavie; Chamaillé, Lise; Baghdadi, Nicolas; Lo Seen, Danny
2010-02-01
Recent studies have highlighted the potential role of water in the transmission of avian influenza (AI) viruses and the existence of often interacting variables that determine the survival rate of these viruses in water; the two main variables are temperature and salinity. Remote sensing has been used to map and monitor water bodies for several decades. In this paper, we review satellite image analysis methods used for water detection and characterization, focusing on the main variables that influence AI virus survival in water. Optical and radar imagery are useful for detecting water bodies at different spatial and temporal scales. Methods to monitor the temperature of large water surfaces are also available. Current methods for estimating other relevant water variables such as salinity, pH, turbidity and water depth are not presently considered to be effective.
USDA-ARS?s Scientific Manuscript database
CO2 enrichment may increase N input to ecosystems by increasing N2 fixation, but the fixation-CO2 response depends on factors such as soil water availability that are influenced by both CO2 and soil properties. We used the d15N natural abundance method to determine N2 fixation by the legume Desmant...
Correlation of published data on the solubility of methane in H/sub 2/O-NaCl solutions
DOE Office of Scientific and Technical Information (OSTI.GOV)
Coco, L.T.; Johnson, A.E. Jr.; Bebout, D.G.
1981-01-01
A new correlation of the available published data for the solubility of methane in water was developed, based on fundamental thermodynamic relationships. An empirical relationship for the salting-out coefficient of NaCl for methane solubility in water was determined as a function of temperature. Root mean square and average deviations for the new correlation, the Haas correlation, and the revised Blount equation are compared.
NASA Astrophysics Data System (ADS)
Redmond, M. D.; Kelsey, K.; Urza, A.; Barger, N. N.
2015-12-01
Forest and woodland ecosystems play a crucial role in the global carbon cycle and may be strongly affected by changing climate. Here we use an individual-based approach to model piñon pine (Pinus edulis) radial growth responses to climate across gradients of environmental stress. We sampled piñon pine trees at 24 sites across southwestern Colorado that varied in soil available water capacity, elevation, and latitude, obtaining a total of 552 pinon pine tree ring series. We used linear mixed effect models to assess piñon pine growth responses to climate and site-level environmental stress (mean annual climatic water deficit and soil available water capacity). Using a similar modeling approach, we also determined long-term growth trends across our gradients of environmental stress. Piñon pine growth was strongly positively associated with winter precipitation and strongly negatively associated with summer vapor pressure deficit. However, the strength of the relationship between winter precipitation and piñon pine growth was affected by site-level environmental stress. Trees at sites with greater climatic water deficit (i.e. hotter, drier sites) were more sensitive to winter precipitation. Interestingly, trees at sites with greater soil available water capacity were also more sensitive to winter precipitation, as these trees had much higher growth rates during years of high precipitation. We found weak evidence of long-term declines in piñon growth rates over the past century within our study area. Growth trends overtime did vary across our soil available water capacity gradient: trees growing at sites with higher soil available water capacity responded more positively to the cool, wet climate conditions of the 1910s and 1980s, whereas tree growth rates at sites with lower soil available water capacity declined more linearly over the last century. Our findings suggest that the sensitivity of woodland ecosystems to changing climate will vary across the landscape due to differences in edaphic and physiographic factors. These results support recent dendroecology studies that emphasize the need to use a more individual-based approach to enhance our understanding of tree growth responses to climate.
Zanethia D. Choice; Thomas K. Frazer; Charles A. Jacoby
2014-01-01
Seagrasses around the world are threatened by human activities that degrade water quality and reduce light availability. In this study, light requirements were determined for four common and abundant seagrasses along the Gulf coast of peninsular Florida using a threshold detecting algorithm. Light requirements ranged from 8% to 10% of surface irradiance for Halophila...
Occurrence and availability of ground water in the Athens region, northeastern Georgia
Radtke, D.B.; Cressler, C.W.; Perlman, H.A.; Blanchard, H.E.; McFadden, K.W.; Brooks, Rebekah
1986-01-01
A study was conducted to assess the occurrence and availability of groundwater in the crystalline rocks of the Piedmont area in northeastern Georgia and to determine whether groundwater is a viable alternative or supplemental source for industrial, public and private supplies. The area is underlain by a variety of metamorphic and igneous rocks. The quantity of water that a rock unit can supply to wells is determined by the number, capacity, and interconnection of the secondary openings. Of an estimated 10,000 successful wells drilled in the Athens Region, 972 wells are reported by drilling contractors to supply from 20 to 300 gal/min. Studies of well sites revealed that high yielding wells can be developed only where the water bearing units have undergone significant increases in secondary permeability. This occurs mainly in association with (1) contact zones between rock units of contrasting character, (2) contact zones within multilayered rock units, (3) fault zones, (4) stress-relief fractures, and (5) shear zones. Groundwater may be a viable alternative or supplemental source for industrial, public, and private supplies in much of the Athens Region. In 1980, groundwater made up 38% (18 million gal/day) of the total water used in the area. Yields of 20 to more than 200 gal/min are obtained from wells throughout most of the region, and the water is generally of good chemical quality and is suitable for drinking and many other uses. Concentrations of dissolved constituents are fairly consistent throughout the area. Except for iron, manganese, and fluoride, dissolved constituents rarely exceed drinking water standards. (Lantz-PTT)
NASA Astrophysics Data System (ADS)
Vallet, A.; Bertrand, C.; Fabbri, O.; Mudry, J.
2015-01-01
Pore water pressure build-up by recharge of underground hydrosystems is one of the main triggering factors of deep-seated landslides. In most deep-seated landslides, pore water pressure data are not available since piezometers, if any, have a very short lifespan because of slope movements. As a consequence, indirect parameters, such as the calculated recharge, are the only data which enable understanding landslide hydrodynamic behaviour. However, in landslide studies, methods and recharge-area parameters used to determine the groundwater recharge are rarely detailed. In this study, the groundwater recharge is estimated with a soil-water balance based on characterisation of evapotranspiration and parameters characterising the recharge area (soil available water capacity, runoff and vegetation coefficient). A workflow to compute daily groundwater recharge is developed. This workflow requires the records of precipitation, air temperature, relative humidity, solar radiation and wind speed within or close to the landslide area. The determination of the parameters of the recharge area is based on a spatial analysis requiring field observations and spatial data sets (digital elevation models, aerial photographs and geological maps). This study demonstrates that the performance of the correlation with landslide displacement velocity data is significantly improved using the recharge estimated with the proposed workflow. The coefficient of determination obtained with the recharge estimated with the proposed workflow is 78% higher on average than that obtained with precipitation, and is 38% higher on average than that obtained with recharge computed with a commonly used simplification in landslide studies (recharge = precipitation minus non-calibrated evapotranspiration method).
Shoda, Megan E.; Nowell, Lisa H.; Stone, Wesley W.; Sandstrom, Mark W.; Bexfield, Laura M.
2018-04-02
In 2013, the U.S. Geological Survey National Water Quality Laboratory (NWQL) made a new method available for the analysis of pesticides in filtered water samples: laboratory schedule 2437. Schedule 2437 is an improvement on previous analytical methods because it determines the concentrations of 225 fungicides, herbicides, insecticides, and associated degradates in one method at similar or lower concentrations than previously available methods. Additionally, the pesticides included in schedule 2437 were strategically identified in a prioritization analysis that assessed likelihood of occurrence, prevalence of use, and potential toxicity. When the NWQL reports pesticide concentrations for analytes in schedule 2437, the laboratory also provides supplemental information useful to data users for assessing method performance and understanding data quality. That supplemental information is discussed in this report, along with an initial analysis of analytical recovery of pesticides in water-quality samples analyzed by schedule 2437 during 2013–2015. A total of 523 field matrix spike samples and their paired environmental samples and 277 laboratory reagent spike samples were analyzed for this report (1,323 samples total). These samples were collected in the field as part of the U.S. Geological Survey National Water-Quality Assessment groundwater and surface-water studies and as part of the NWQL quality-control program. This report reviews how pesticide samples are processed by the NWQL, addresses how to obtain all the data necessary to interpret pesticide concentrations, explains the circumstances that result in a reporting level change or the occurrence of a raised reporting level, and describes the calculation and assessment of recovery. This report also discusses reasons why a data user might choose to exclude data in an interpretive analysis and outlines the approach used to identify the potential for decreased data quality in the assessment of method recovery. The information provided in this report is essential to understanding pesticide data determined by schedule 2437 and should be reviewed before interpretation of these data.
Ground-water resources data for Baldwin County, Alabama
Robinson, James L.; Moreland, Richard S.; Clark, Amy E.
1996-01-01
Geologic and hydrologic data for 237 wells were collected, and water-levels in 223 wells in Baldwin and Escambia Counties were measured. Long-term water water-level data, available for many wells, indicate that ground-water levels in most of Baldwin County show no significant trends for the period of record. However, ground-water levels have declined in the general vicinity of Spanish Fort and Daphne, and ground-water levels in the Gulf Shores and Orange Beach areas are less than 5 feet above sea level in places. The quality of ground water generally is good, but problems with iron, sulfur, turbidity, and color occur. The water from most private wells in Baldwin County is used without treatment or filtration. Alabama public- health law requires that water from public-supply wells be chlorinated. Beyond that, the most common treatment of ground water by public-water suppliers in Baldwin County consists of pH adjustment, iron removal, and aeration. The transmissivity of the Miocene-Pliocene aquifer was determined at 10 locations in Baldwin County. Estimates of transmissivity ranged from 700 to 5,400 feet squared per day. In general, aquifer transmissivity was greatest in the southeastern part of the county, and least in the western part of the county near Mobile Bay. A storage coefficient of 1.5 x 10-3 was determined for the Miocene-Pliocene aquifer near Loxley.
Quesada, Carlos Alberto; Hodnett, Martin G; Breyer, Lacê M; Santos, Alexandre J B; Andrade, Sérgio; Miranda, Heloisa S; Miranda, Antonio Carlos; Lloyd, Jon
2008-03-01
Changes in soil water content were determined in two cerrado (sensu stricto) areas with contrasting fire history and woody vegetation density. The study was undertaken near Brasília, Brazil, from 1999 to 2001. Soil water content was measured with a neutron probe in three access tubes per site to a depth of 4.7 m. One site has been protected from fire for more than 30 years and, as a consequence, has a high density of woody plants. The other site had been frequently burned, and has a high herbaceous vegetation density and less woody vegetation. Soil water uptake patterns were strongly seasonal, and despite similarities in hydrological processes, the protected area systematically used more water than the burned area. Three temporarily contiguous patterns of water absorption were differentiated, characterized by variation in the soil depth from which water was extracted. In the early dry season, vegetation used water from throughout the soil profile but with a slight preference for water in the upper soil layers. Toward the peak of the dry season, vegetation had used most or all available water from the surface to a depth of 1.7 m, but continued to extract water from greater depths. Following the first rains, all water used was from the recently wetted upper soil layers only. Evaporation rates were a linear function of soil water availability, indicating a strong coupling of atmospheric water demand and the physiological response of the vegetation.
Inverse models: A necessary next step in ground-water modeling
Poeter, E.P.; Hill, M.C.
1997-01-01
Inverse models using, for example, nonlinear least-squares regression, provide capabilities that help modelers take full advantage of the insight available from ground-water models. However, lack of information about the requirements and benefits of inverse models is an obstacle to their widespread use. This paper presents a simple ground-water flow problem to illustrate the requirements and benefits of the nonlinear least-squares repression method of inverse modeling and discusses how these attributes apply to field problems. The benefits of inverse modeling include: (1) expedited determination of best fit parameter values; (2) quantification of the (a) quality of calibration, (b) data shortcomings and needs, and (c) confidence limits on parameter estimates and predictions; and (3) identification of issues that are easily overlooked during nonautomated calibration.Inverse models using, for example, nonlinear least-squares regression, provide capabilities that help modelers take full advantage of the insight available from ground-water models. However, lack of information about the requirements and benefits of inverse models is an obstacle to their widespread use. This paper presents a simple ground-water flow problem to illustrate the requirements and benefits of the nonlinear least-squares regression method of inverse modeling and discusses how these attributes apply to field problems. The benefits of inverse modeling include: (1) expedited determination of best fit parameter values; (2) quantification of the (a) quality of calibration, (b) data shortcomings and needs, and (c) confidence limits on parameter estimates and predictions; and (3) identification of issues that are easily overlooked during nonautomated calibration.
Event Water Balance and Recharge at the Panola Mountain Research Watershed, Georgia, U.S.A.
NASA Astrophysics Data System (ADS)
Riley, J. W.; Aulenbach, B. T.
2016-12-01
Investigating catchment storage and runoff pathways allows a better mechanistic understanding of stream flow generation processes. This information can be used to elucidate processes such as those influencing baseflow that support human consumption and ecological needs. Here we describe storm runoff water budgets from 483 rain events to determine the conditions under which precipitation infiltrates to deeper storage that supports baseflow. Further, we examine the storage and recharge behavior of different storm characteristics and antecedent conditions. We use a simple water budget approach to achieve this in which Deep Recharge = (Precipitation) - (Storm Runoff) - (Event Change in Soil Storage). Hydrograph separation was used to determine the storm periods and split storm runoff into baseflow and quickflow. Quickflow was assumed to account for the event water lost to the stream. Data from volumetric water content sensors were used to calculate the soil profile water storage and the change in water storage over the course of an event. The remaining water after these two components was assumed to represent water available for deeper recharge. The median event quickflow:precipitation ratio was 11.8%. Event soil moisture recharge in the top one meter of soil accounted for a median of 65.3% of precipitation. Quickflow and shallow soil moisture recharge accounted for a median of 77.1% of the precipitation delivered to the watershed. Water budgets indicated that 43% of the events provided water for deeper recharge. Of these events, however, only 28% provided 50 mm or more of deep recharge. Because the focus was on events, when humidity was high and the vapor pressure deficit (VPD) was low, we ignored the role of evapotranspiration. However, interception, which was not accounted for, would have resulted in less storm precipitation than was measured at the watershed rain gage. Furthermore, transpiration may have altered the post-storm water balance when VPD increased and before excess water was able to infiltrate to deeper storage. While uncertainty remains, this study provided insight into the partitioning of incoming precipitation and the conditions under which water was likely available for deeper recharge.
Krstolic, Jennifer L.; Ramey, R. Clay
2012-01-01
The ecological habitat requirements of aquatic organisms and recreational streamflow requirements of the South Fork Shenandoah River were investigated by the U.S. Geological Survey in cooperation with the Central Shenandoah Valley Planning District Commission, the Northern Shenandoah Valley Regional Commission, and Virginia Commonwealth University. Physical habitat simulation modeling was conducted to examine flow as a major determinant of physical habitat availability and recreation suitability using field-collected hydraulic habitat variables such as water depth, water velocity, and substrate characteristics. Fish habitat-suitability criteria specific to the South Fork Shenandoah River were developed for sub-adult and adult smallmouth bass (Micropterus dolomieu), juvenile and sub-adult redbreast sunfish (Lepomis auritus), spotfin or satinfin shiner (Cyprinella spp), margined madtom (Noturus insignis),and river chub (Nocomis micropogon). Historic streamflow statistics for the summer low-flow period during July, August, and September were used as benchmark low-flow conditions and compared to habitat simulation results and water-withdrawal scenarios based on 2005 withdrawal data. To examine habitat and recreation characteristics during droughts, daily fish habitat or recreation suitability values were simulated for 2002 and other selected drought years. Recreation suitability during droughts was extremely low, because the modeling demonstrated that suitable conditions occur when the streamflows are greater than the 50th percentile flow for July, August, and September. Habitat availability for fish is generally at a maximum when streamflows are between the 75th and 25th percentile flows for July, August, and September. Time-series results for drought years, such as 2002, showed that extreme low-flow conditions less than the 5th percentile of flow for July, August, and September corresponded to below-normal habitat availability for both game and nongame fish in the upper section of the river. For the middle section near Luray, margined madtom and river chub habitat area were below normal, whereas adult and sub-adult smallmouth bass habitat area remained near the median expected available habitat. In the lower section near Front Royal, time-series results for adult smallmouth bass, sub-adult smallmouth bass, and margined madtom habitat were below normal when streamflows were below the 10th percentile flow for July, August, and September. All other species of fish had habitat availability within the normal range for July, August, and September. Water-conservation scenarios representing a 50 percent water-withdrawal reduction resulted in game fish habitat availability within the normal range for habitat in upper and middle river sections, instead of below normal conditions which were observed during the 2002 drought. The 50 percent water-withdrawal reduction had no measurable effect on recreation. For nongame fish such as river chub, a 20 percent withdrawal reduction resulted in habitat availability within the normal range for habitat in the upper and middle river sections. Increased water-use scenarios representing a 5 percent increase in water withdrawals resulted in a slight reduction in habitat availability; however, increased withdrawals of 20 and 50 percent resulted in habitat availability substantially less than the 25th habitat percentile, or below normal. Habitat reductions were more pronounced when flows were lower than the 10th percentile flow for July, August, and September. The results show that for normal or wet years, increased water withdrawals are not likely to correspond with extensive habitat loss for game fish or nongame fish. During drought years, however, a 20 to 50 percent increase in water withdrawals may result in below normal habitat availability for game fish throughout the river and nongame fish in the upper and middle sections of the river. These simulations of rare historic drought conditions, such as those observed in 2002, serve as a baseline for development of ecological flow thresholds for drought planning.
Kördel, Werner; Bernhardt, Cornelia; Derz, Kerstin; Hund-Rinke, Kerstin; Harmsen, Joop; Peijnenburg, Willie; Comans, Rob; Terytze, Konstantin
2013-10-15
Nearly all publications dealing with availability or bioavailability of soil pollutants start with the following statement: the determination of total pollutant content will lead to an over-estimation of risk. However, an assessment of contaminated sites should be based on the determination of mobile fractions of pollutants, and the fractions with potential for mobilisation that threaten groundwater and surface water, and the actual and potential fractions available for uptake by plants, soil microflora and soil organisms. After reviewing the literature for method proposals concerning the determination of available/bioavailable fractions of contaminants with respect to leaching, plants, microorganisms (biodegradation) and soil organisms, we propose a testing and assessment scheme for contaminated sites. The proposal includes (i) already accepted and used methods, (ii) methods which are under standardisation, and (iii) methods for which development has just started in order to promote urgently needed research. Copyright © 2013 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Xu, Bingcheng; Deng, Xiping; Zhang, Suiqi; Shan, Lun
2010-10-01
Seedling biomass and allocation, transpiration water use efficiency (TWUE), and species competition between switchgrass ( Panicum virgatum L.) and milkvetch ( Astragalus adsurgens Pall.) were investigated in a pot-cultivated experiment under different levels of water availability. The experiment was conducted using a simple replacement design in which switchgrass and milkvetch were grown in growth chamber with ten seedlings per pot, in three combinations of the two species (0:10, 5:5 and 10:0). Five water treatments included sufficient water supply (HW), gradual soil drying from HW (DHW), moderate water stress (LW), gradual soil drying from LW (DLW), and re-establishment of LW conditions after 12 days of drying from LW (RLW). Water treatments were applied over a 15-day period. Biomass production and its partitioning, and TWUE were determined at the end of the experiment. Species competitive indices (competitive ratio (CR), aggressivity (A) and relative yield total (RYT)) were calculated from the biomass dry weight data for shoots, roots and total biomass. Water stress significantly reduced seedling biomass production but increased root:shoot ratios in both monocultures and mixtures. In the RLW treatment, only switchgrass monocultures displayed compensatory biomass production and TWUE, while both species demonstrated compensatory growth in the mixture. Switchgrass was the dominant species and much more aggressive than milkvetch in the LW treatment, while in the other four treatments milkvetch was the dominant species as measured by the positive value of aggressivity and higher values of CR. The total biomass RYT values of the two species were higher than 1.0, indicating some degree of resource complimentarity. In the two-species mixture, although the biomass production was lower than that of milkvetch in the monoculture, there was better TWUE, especially under low and fluctuating water availability.
NASA Astrophysics Data System (ADS)
Chen, Yizhong; Lu, Hongwei; Li, Jing; Ren, Lixia; He, Li
2017-05-01
This study presents the mathematical formulation and implementations of a synergistic optimization framework based on an understanding of water availability and reliability together with the characteristics of multiple water demands. This framework simultaneously integrates a set of leader-followers-interactive objectives established by different decision makers during the synergistic optimization. The upper-level model (leader's one) determines the optimal pollutants discharge to satisfy the environmental target. The lower-level model (follower's one) accepts the dispatch requirement from the upper-level one and dominates the optimal water-allocation strategy to maximize economic benefits representing the regional authority. The complicated bi-level model significantly improves upon the conventional programming methods through the mutual influence and restriction between the upper- and lower-level decision processes, particularly when limited water resources are available for multiple completing users. To solve the problem, a bi-level interactive solution algorithm based on satisfactory degree is introduced into the decision-making process for measuring to what extent the constraints are met and the objective reaches its optima. The capabilities of the proposed model are illustrated through a real-world case study of water resources management system in the district of Fengtai located in Beijing, China. Feasible decisions in association with water resources allocation, wastewater emission and pollutants discharge would be sequentially generated for balancing the objectives subject to the given water-related constraints, which can enable Stakeholders to grasp the inherent conflicts and trade-offs between the environmental and economic interests. The performance of the developed bi-level model is enhanced by comparing with single-level models. Moreover, in consideration of the uncertainty in water demand and availability, sensitivity analysis and policy analysis are employed for identifying their impacts on the final decisions and improving the practical applications.
Soltani, Maryam; Kerachian, Reza
2018-04-15
In this paper, a new methodology is proposed for the real-time trading of water withdrawal and waste load discharge permits in agricultural areas along the rivers. Total Dissolved Solids (TDS) is chosen as an indicator of river water quality and the TDS load that agricultural water users discharge to the river are controlled by storing a part of return flows in some evaporation ponds. Available surface water withdrawal and waste load discharge permits are determined using a non-linear multi-objective optimization model. Total available permits are then fairly reallocated among agricultural water users, proportional to their arable lands. Water users can trade their water withdrawal and waste load discharge permits simultaneously, in a bilateral, step by step framework, which takes advantage of differences in their water use efficiencies and agricultural return flow rates. A trade that would take place at each time step results in either more benefit or less diverted return flow. The Nucleolus cooperative game is used to redistribute the benefits generated through trades in different time steps. The proposed methodology is applied to PayePol region in the Karkheh River catchment, southwest Iran. Predicting that 1922.7 Million Cubic Meters (MCM) of annual flow is available to agricultural lands at the beginning of the cultivation year, the real-time optimization model estimates the total annual benefit to reach 46.07 million US Dollars (USD), which requires 6.31 MCM of return flow to be diverted to the evaporation ponds. Fair reallocation of the permits, changes these values to 35.38 million USD and 13.69 MCM, respectively. Results illustrate the effectiveness of the proposed methodology in the real-time water and waste load allocation and simultaneous trading of permits. Copyright © 2018 Elsevier Ltd. All rights reserved.
Davis, R.W.
1984-01-01
Among the concepts suggested for the deep disposal of high-level radioactive wastes from nuclear power reactors is the excavation of a repository in suitable crystalline rocks overlain by a thick sequence of sedimentary strata in a hydrogeologic environment that would effectively impede waste transport. To determine the occurrence of such environments in the Eastern United States, a review was made of available sources of published or unpublished information, using the following hydrogeologic criteria:The top of the crystalline basement rock is 1,000 to 4,000 feet below land surface.The crystalline rock is overlain by sedimentary rock whose lowermost part, at least, contains ground water with a dissolved-solids concentration of 10,000 milligrams per liter or more.Shale or clay confining beds overlie the saline-water aquifer.The flow system in the saline-water aquifer is known or determinable from presently available data.All of these hydrogeologic conditions occur in two general areas: (1) parts of Indiana, Ohio, and Kentucky, underlain by part of the geologic structure known as the Cincinnati arch, and (2) parts of the Atlantic Coastal Plain from Georgia to New Jersey.
Atmospheric absorption of terahertz radiation and water vapor continuum effects
NASA Astrophysics Data System (ADS)
Slocum, David M.; Slingerland, Elizabeth J.; Giles, Robert H.; Goyette, Thomas M.
2013-09-01
The water vapor continuum absorption spectrum was investigated using Fourier Transform Spectroscopy. The transmission of broadband terahertz radiation from 0.300 to 1.500 THz was recorded for multiple path lengths and relative humidity levels. The absorption coefficient as a function of frequency was determined and compared with theoretical predictions and available water vapor absorption data. The prediction code is able to separately model the different parts of atmospheric absorption for a range of experimental conditions. A variety of conditions were accurately modeled using this code including both self and foreign gas broadening for low and high water vapor pressures for many different measurement techniques. The intensity and location of the observed absorption lines were also in good agreement with spectral databases. However, there was a discrepancy between the resonant line spectrum simulation and the observed absorption spectrum in the atmospheric transmission windows caused by the continuum absorption. A small discrepancy remained even after using the best available data from the literature to account for the continuum absorption. From the experimental and resonant line simulation spectra the air-broadening continuum parameter was calculated and compared with values available in the literature.
NASA Astrophysics Data System (ADS)
Budiarso; Adanta, Dendy; Warjito; Siswantara, A. I.; Saputra, Pradhana; Dianofitra, Reza
2018-03-01
Rapid economic and population growth in Indonesia lead to increased energy consumption, including electricity needs. Pico hydro is considered as the right solution because the cost of investment and operational cost are fairly low. Additionally, Indonesia has many remote areas with high hydro-energy potential. The overshot waterwheel is one of technology that is suitable to be applied in remote areas due to ease of operation and maintenance. This study attempts to optimize bucket dimensions with the available conditions. In addition, the optimization also has a good impact on the amount of generated power because all available energy is utilized maximally. Analytical method is used to evaluate the volume of water contained in bucket overshot waterwheel. In general, there are two stages performed. First, calculation of the volume of water contained in each active bucket is done. If the amount total of water contained is less than the available discharge in active bucket, recalculation at the width of the wheel is done. Second, calculation of the torque of each active bucket is done to determine the power output. As the result, the mechanical power generated from the waterwheel is 305 Watts with the efficiency value of 28%.
Water production in comet 81P/Wild 2 as determined by Herschel/HIFI
NASA Astrophysics Data System (ADS)
de Val-Borro, M.; Hartogh, P.; Crovisier, J.; Bockelée-Morvan, D.; Biver, N.; Lis, D. C.; Moreno, R.; Jarchow, C.; Rengel, M.; Szutowicz, S.; Banaszkiewicz, M.; Bensch, F.; Błęcka, M. I.; Emprechtinger, M.; Encrenaz, T.; Jehin, E.; Küppers, M.; Lara, L.-M.; Lellouch, E.; Swinyard, B. M.; Vandenbussche, B.; Bergin, E. A.; Blake, G. A.; Blommaert, J. A. D. L.; Cernicharo, J.; Decin, L.; Encrenaz, P.; de Graauw, T.; Hutsemékers, D.; Kidger, M.; Manfroid, J.; Medvedev, A. S.; Naylor, D. A.; Schieder, R.; Stam, D.; Thomas, N.; Waelkens, C.; Szczerba, R.; Saraceno, P.; di Giorgio, A. M.; Philipp, S.; Klein, T.; Ossenkopf, V.; Zaal, P.; Shipman, R.
2010-10-01
The high spectral resolution and sensitivity of Herschel/HIFI allows for the detection of multiple rotational water lines and accurate determinations of water production rates in comets. In this Letter we present HIFI observations of the fundamental 110-101 (557 GHz) ortho and 111-00 (1113 GHz) para rotational transitions of water in comet 81P/Wild 2 acquired in February 2010. We mapped the extent of the water line emission with five point scans. Line profiles are computed using excitation models which include excitation by collisions with electrons and neutrals and solar infrared radiation. We derive a mean water production rate of 1.0 × 1028 molecules s-1 at a heliocentric distance of 1.61 AU about 20 days before perihelion, in agreement with production rates measured from the ground using observations of the 18-cm OH lines. Furthermore, we constrain the electron density profile and gas kinetic temperature, and estimate the coma expansion velocity by fitting the water line shapes. Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA.Figure 5 (page 5) is only available in electronic form at http://www.aanda.org
Finding water scarcity amid abundance using human–natural system models
Amos, Adell; Bigelow, Daniel P.; Chang, Heejun; Conklin, David R.; Haggerty, Roy; Langpap, Christian; Moore, Kathleen; Mote, Philip W.; Nolin, Anne W.; Plantinga, Andrew J.; Schwartz, Cynthia L.; Tullos, Desiree; Turner, David P.
2017-01-01
Water scarcity afflicts societies worldwide. Anticipating water shortages is vital because of water’s indispensable role in social-ecological systems. But the challenge is daunting due to heterogeneity, feedbacks, and water’s spatial-temporal sequencing throughout such systems. Regional system models with sufficient detail can help address this challenge. In our study, a detailed coupled human–natural system model of one such region identifies how climate change and socioeconomic growth will alter the availability and use of water in coming decades. Results demonstrate how water scarcity varies greatly across small distances and brief time periods, even in basins where water may be relatively abundant overall. Some of these results were unexpected and may appear counterintuitive to some observers. Key determinants of water scarcity are found to be the cost of transporting and storing water, society’s institutions that circumscribe human choices, and the opportunity cost of water when alternative uses compete. PMID:29078299
Use of free water by nesting lesser prairie-chickens
Robinson, Samantha G.; Haukos, David A.; Sullins, Daniel S.; Plumb, Reid T.
2016-01-01
The lesser prairie-chicken (Tympanuchus pallidicinctus) is a grassland grouse of semiarid regions. Use of free water has been hypothesized as necessary for egg formation during drought. We assessed the use of hydrogen isotopes (deuterium, δ2H) to determine if female lesser prairie-chickens use and incorporate free water during egg formation by testing the relationship between isotope ratios in available free water and eggshells. We collected eggshells from 124 nests and 282 free water samples from three sites in Kansas in 2013 and 2014. Eggshells had δ2H values similar to free water in the year of severe drought but were dissimilar the year with lessened drought severity. With an established link between lesser prairie-chicken eggshells and free water during severe drought, we have identified a mechanism behind observations of lesser prairie-chicken water use. We have demonstrated that hydrogen isotopes can be used to test research questions related to use of free water.
NASA Astrophysics Data System (ADS)
Tsukerman, V. A.; Gudkov, A. V.; Ivanov, S. V.
The paper discusses problems associated with the existing crisis of water scarcity in the modern conditions of the global water use. Available alternative sources of fresh water may be underground and surface waters of the North and the Arctic. Investigated the current situation and condition of fresh water resources in the technological and industrial development of the North and Arctic. The necessity of developing and using green technologies and measures to prevent pollution of surface and ground water from industrial sectors of the Northern regions is shown. Studied modern technologies and techniques for monitoring groundwater and determination of their age in order to avoid and prevent the effects of environmental contaminants. The ways of use of innovative production technologies of fresh and clean water of north Russia for sustainable development, and delivery of water in the needy regions of the world are investigated.
NASA Astrophysics Data System (ADS)
Brown, C.; Ray, P. A.; Freeman, S.
2016-12-01
Societal need for improved water management and concerns for the long-term sustainability of water resources systems are prominent around the world. The continued susceptibility of society to the harmful effects of hydrologic variability, pervasive concerns related to climate change and the emergent awareness of devastating effects of current practice on aquatic ecosystems all illustrate our limited understanding of how water ought to be managed in a dynamic world. To address these challenges, new problem solving approaches are required that acknowledge uncertainties, incorporate best available information, and link engineering design principles, typically based on determinism, with our best geoscience-based understanding of planetary change. In this presentation, we present and demonstrate a framework for developing water planning and management strategies that are resilient in the face of future uncertainties and our limited ability to anticipate the future. The approach begins with stakeholder engagement and decision framing to elicit relevant context, uncertainties, choices and connections that drive planning and serve as an entry point to exploring possible futures. The result is the development of water strategies that are informed by the best available predictive information and designed to perform well over a future of change. Examples from around the world are presented to illustrate the methodology.
Conceptualizing the dynamics of a drought affected agricultural community
NASA Astrophysics Data System (ADS)
Kuil, Linda; Carr, Gemma; Viglione, Alberto; Bloeschl, Guenter
2015-04-01
Climate and especially water availability and variability play an important role in the development of our societies. This can be seen through the vast investments that are made in reaching water security and the economic impact regions experience when the rains fail. However, the limit of available fresh water is increasingly felt as our population increases and the demand for water continues to rise. But how do we as society respond? Are periods of drought making us more resilient? The answer to this question is sought through the development of a stylized model that is built within the spirit of the Easter Island model by Brander and Taylor and aimed at capturing the essence of the dynamics of water supply and demand. By explicitly incorporating feedbacks, but keeping the framework simple, the model seeks to understand qualitative behavior of our socio-hydrological system as opposed to predicting exact pathways. The model shows that carrying capacity dynamics are a determining factor for continued growth. Future work will explore the underlying relationships further, among others, through examination of case studies.
NASA Astrophysics Data System (ADS)
Bollozos, I.; Yniguez, A. T.; Palermo, J. H.; Cabrera, O. C.; Villanoy, C. L.
2013-12-01
The waters in the eastern part of Luzon are highly influenced by the western boundary current system of the western Pacific brought about by the bifurcation of the North Equatorial Current into the Kuroshio and Mindanao Current. Eddies are formed with varying intensities as an effect of the ENSO cycle. Three spatial zones were identified according to prominent current movements and circulations observed during the summer 2011 and 2012 oceanographic cruises. These events also affect the productivity in the surrounding waters. Plankton samples were collected to determine the relative abundances of major groups representing three trophic levels. The abundance and composition of phyto- and zooplankton major groups slightly varied among the zones. Gut analysis of fish larvae was then conducted to determine potential prey preference and linked to the phyto- and zooplankton densities.
Hunt, Pamela K.B.; Runkle, Donna L.
1985-01-01
The purpose of this investigation was to determine the availability, quantity and quality of groundwater from three principal aquifers in West-Central Iowa, the alluvial, buried channel, Basal Pleistocene and the Dakota aquifers. Specific objectives were to: (1) determine the location, extent and the nature of these aquifers; (2) evaluate the occurrence and movement of groundwater, including the sources of recharge and discharge; (3) estimate the quantities of water stored in the aquifers; (4) estimate the potential yields of wells tapping the aquifers; (5) estimate the water use; and (6) describe the chemical quality of the groundwater. This report is the compilation of the data collected during the investigation and has the purpose of providing a reference for an interpretive report describing groundwater resources and a bedrock topography map of the study area.
NASA Astrophysics Data System (ADS)
Wada, Y.; van Beek, L. P. H.; Bierkens, M. F. P.
2011-12-01
During the past decades, human water use has more than doubled, yet available freshwater resources are finite. As a result, water scarcity has been prevalent in various regions of the world. Here, we present the first global assessment of past development of water stress considering not only climate variability but also growing water demand, desalinated water use and non-renewable groundwater abstraction over the period 1960-2001 at a spatial resolution of 0.5°. Agricultural water demand is estimated based on past extents of irrigated areas and livestock densities. We approximate past economic development based on GDP, energy and household consumption and electricity production, which are subsequently used together with population numbers to estimate industrial and domestic water demand. Climate variability is expressed by simulated blue water availability defined by freshwater in rivers, lakes, wetlands and reservoirs by means of the global hydrological model PCR-GLOBWB. We thus define blue water stress by comparing blue water availability with corresponding net total blue water demand by means of the commonly used, Water Scarcity Index. The results show a drastic increase in the global population living under water-stressed conditions (i.e. moderate to high water stress) due to growing water demand, primarily for irrigation, which has more than doubled from 1708/818 to 3708/1832 km3 yr-1 (gross/net) over the period 1960-2000. We estimate that 800 million people or 27% of the global population were living under water-stressed conditions for 1960. This number is eventually increased to 2.6 billion or 43% for 2000. Our results indicate that increased water demand is a decisive factor for heightened water stress in various regions such as India and North China, enhancing the intensity of water stress up to 200%, while climate variability is often a main determinant of extreme events. However, our results also suggest that in several emerging and developing economies (e.g. India, Turkey, Romania and Cuba) some of past extreme events were anthropogenically driven due to increased water demand rather than being climate-induced.
Tarroja, Brian; AghaKouchak, Amir; Sobhani, Reza; Feldman, David; Jiang, Sunny; Samuelsen, Scott
2014-11-01
A study was conducted to compare the technical potential and effectiveness of different water supply options for securing water availability in a large-scale, interconnected water supply system under historical and climate-change augmented inflow and demand conditions. Part 2 of the study focused on determining the greenhouse gas and renewable energy utilization impacts of different pathways to stabilize major surface reservoir levels. Using a detailed electric grid model and taking into account impacts on the operation of the water supply infrastructure, the greenhouse gas emissions and effect on overall grid renewable penetration level was calculated for each water supply option portfolio that successfully secured water availability from Part 1. The effects on the energy signature of water supply infrastructure were found to be just as important as that of the fundamental processes for each option. Under historical (baseline) conditions, many option portfolios were capable of securing surface reservoir levels with a net neutral or negative effect on emissions and a benefit for renewable energy utilization. Under climate change augmented conditions, however, careful selection of the water supply option portfolio was required to prevent imposing major emissions increases for the system. Overall, this analysis provided quantitative insight into the tradeoffs associated with choosing different pathways for securing California's water supply. Copyright © 2014 Elsevier B.V. All rights reserved.
Moffatt, R.L.; Jones, M.L.
1984-01-01
The Bruneau plateau in south-central Idaho consists of about 889 ,600 acres of potentially irrigable land. About 112,200 of these acres have been developed for agriculture; 11,200 acres are irrigated with ground water, and the remaining acreage is irrigated with water from the Snake and Bruneau rivers and Salmon Falls Creek. On the basis of present usage, about 158,000 acre-feet of water per year are needed to develop an additional 63,000 acres. About 438,000 acre-feet per year are needed to irrigate existing and newly developed lands in dry years when streamflow in the Snake River at Milner Dam is inadequate to meet appropriated needs. Pumping lifts of about 400-600 feet and low well yields on the Bruneau plateau probably preclude large-scale irrigation development solely from local ground-water resources. However, supplemental sources of irrigation water are available from a perched-water aquifer, a thermal aquifer, and the regional aquifer adjacent to the plateau. About 100,000-115,000 acre-feet per year of water probably could be withdrawn from the perched and regional aquifers and conveyed to the plateau without serious impact on local ground-water resources. The amount of water that could be safely withdrawn from the thermal aquifer was not determined. (USGS)
Hand volume estimates based on a geometric algorithm in comparison to water displacement.
Mayrovitz, H N; Sims, N; Hill, C J; Hernandez, T; Greenshner, A; Diep, H
2006-06-01
Assessing changes in upper extremity limb volume during lymphedema therapy is important for determining treatment efficacy and documenting outcomes. Although arm volumes may be determined by tape measure, the suitability of circumference measurements to estimate hand volumes is questionable because of the deviation in circularity of hand shape. Our aim was to develop an alternative measurement procedure and algorithm for routine use to estimate hand volumes. A caliper was used to measure hand width and depth in 33 subjects (66 hands) and volumes (VE) were calculated using an elliptical frustum model. Using regression analysis and limits of agreement (LOA), VE was compared to volumes determined by water displacement (VW), to volumes calculated from tape-measure determined circumferences (VC), and to a trapezoidal model (VT). VW and VE (mean +/- SD) were similar (363 +/- 98 vs. 362 +/-100 ml) and highly correlated; VE = 1.01VW -3.1 ml, r=0.986, p<0.001, with LOA of +/- 33.5 ml and +/- 9.9 %. In contrast, VC (480 +/- 138 ml) and VT (432 +/- 122 ml) significantly overestimated volume (p<0.0001). These results indicate that the elliptical algorithm can be a useful alternative to water displacement when hand volumes are needed and the water displacement method is contra-indicated, impractical to implement, too time consuming or not available.
Sensitivity of GRACE-derived estimates of groundwater-level changes in southern Ontario, Canada
NASA Astrophysics Data System (ADS)
Hachborn, Ellen; Berg, Aaron; Levison, Jana; Ambadan, Jaison Thomas
2017-12-01
Amidst changing climates, understanding the world's water resources is of increasing importance. In Ontario, Canada, low water conditions are currently assessed using only precipitation and watershed-based stream gauges by the Conservation Authorities in Ontario and the Ministry of Natural Resources and Forestry. Regional groundwater-storage changes in Ontario are not currently measured using satellite data by research institutes. In this study, contributions from the Gravity Recovery and Climate Experiment (GRACE) data are compared to a hydrogeological database covering southern Ontario from 2003 to 2013, to determine the suitability of GRACE total water storage estimates for monitoring groundwater storage in this location. Terrestrial water storage data from GRACE were used to determine monthly groundwater storage (GWS) anomaly values. GWS values were also determined by multiplying groundwater-level elevations (from the Provincial Groundwater Monitoring Network wells) by specific yield. Comparisons of GRACE-derived GWS to well-based GWS data determined that GRACE is sufficiently sensitive to obtain a meaningful signal in southern Ontario. Results show that GWS values produced by GRACE are useful for identifying regional changes in groundwater storage in areas with limited available hydrogeological characterization data. Results also indicate that GRACE may have an ability to forecast changes in groundwater storage, which will become useful when monitoring climate shifts in the near future.
NASA Astrophysics Data System (ADS)
Garner, C. B.; Boyle, D. P.; Lamorey, G. W.; Bassett, S. D.
2007-12-01
The demand for water in the southwestern United States has increased in tandem with a rapid growth of population over the past 50 years. With ever increasing demands being placed on available water supplies, improving water management becomes crucial to the sustainability of the region's water resources. The National Science Foundation (NSF) Science and Technology Center (STC) for the Sustainability of semi-Arid Hydrology and Riparian Areas (SAHRA) is interested in the feasibility of water leasing as a method for more efficiently distributing water among competing users. Economists working on the project will run water leasing simulations in an auction-type environment to understand the pros and cons of water leasing in a free market system. To include hydrologic processes in the water leasing simulations, an MMS-PRMS hydrologic model was developed for a portion of the Middle Rio Grande Basin (MRGB) near Albuquerque, New Mexico. This portion of the MRGB contains a detailed network of diversions, canals, and drains that transport water through the system. In order to capture the complexity of the system, the model was developed using the highest resolution information available. In the model, each Hydrologic Response Unit (HRU) is represented as a trader. To achieve the 15 trader limit desired by economists, the model structure was simplified using two basic constraints; 1) HRUs having a common source and point of return to the river were lumped; and 2) HRUs with less than 20% agricultural land use were omitted from the auction simulations. A new Evapotranspiration (ET) module was implemented in the model to better estimate ET associated with different crops. Modules were also developed so that the end user has the flexibility to manipulate water deliveries based on crop type and land use. The MMS- PRMS model for the MRGB should help economists determine if the incentive to profit by selling or buying water can make more efficient use of the available water supply.
Colombi, Tino; Torres, Lorena Chagas; Walter, Achim; Keller, Thomas
2018-06-01
Water is the most limiting resource for global crop production. The projected increase of dry spells due to climate change will further increase the problem of water limited crop yields. Besides low water abundance and availability, water limitations also occur due to restricted water accessibility. Soil penetration resistance, which is largely influenced by soil moisture, is the major soil property regulating root elongation and water accessibility. Until now the interactions between soil penetration resistance, root system properties, water uptake and crop productivity are rarely investigated. In the current study we quantified how interactive effects between soil penetration resistance, root architecture and water uptake affect water accessibility and crop productivity in the field. Maize was grown on compacted and uncompacted soil that was either tilled or remained untilled after compaction, which resulted in four treatments with different topsoil penetration resistance. Higher topsoil penetration resistance caused root systems to be shallower. This resulted in increased water uptake from the topsoil and hence topsoil drying, which further increased the penetration resistance in the uppermost soil layer. As a consequence of this feedback, root growth into deeper soil layers, where water would have been available, was reduced and plant growth decreased. Our results demonstrate that soil penetration resistance, root architecture and water uptake are closely interrelated and thereby determine the potential of plants to access soil water pools. Hence, these interactions and their feedbacks on water accessibility and crop productivity have to be accounted for when developing strategies to alleviate water limitations in cropping systems. Copyright © 2018 Elsevier B.V. All rights reserved.
A new experimental method to determine the sorption isotherm of a liquid in a porous medium.
Ouoba, Samuel; Cherblanc, Fabien; Cousin, Bruno; Bénet, Jean-Claude
2010-08-01
Sorption from the vapor phase is an important factor controlling the transport of volatile organic compounds (VOCs) in the vadose zone. Therefore, an accurate description of sorption behavior is essential to predict the ultimate fate of contaminants. Several measurement techniques are available in the case of water, however, when dealing with VOCs, the determination of sorption characteristics generally relies on gas chromatography. To avoid some drawbacks associated with this technology, we propose a new method to determine the sorption isotherm of any liquid compounds adsorbed in a soil. This method is based on standard and costless transducers (gas pressure, temperature) leading to a simple and transportable experimental device. A numerical estimation underlines the good accuracy and this technique is validated on two examples. Finally, this method is applied to determine the sorption isotherm of three liquid compounds (water, heptane, and trichloroethylene) in a clayey soil.
Research by the U.S. Geological Survey on organic materials in water
Baker, Robert Andrew
1976-01-01
The U.S. Geological Survey has responsibility for investigating the Nation's water resources for source, availability, quantity, and quality. This paper describes the Geological Survey's research on organic substances in water and fluvial sediments. Results and ongoing studies are examined. Typical research includes: Separation, concentration, and chromatographic identification of volatile acids; free-flow electrophoresis fractionation of natural organic materials; identification of chlorinated insecticides in suspended sediments and bottom materials; fate of organics following underground disposal; determination of humic and fulvic acid stability constants and characterizations; identification of low-molecular weight chloroorganic constituents in water; PCB (polychlorinated biphenyl compound) distribution in aquatic environments; dissolved organic carbon in ground water; and improvement in separation and concentration schemes prior to analyses.
Federal Register 2010, 2011, 2012, 2013, 2014
2013-05-31
...This action announces the U.S. Environmental Protection Agency's (EPA's) approval of alternative testing methods for use in measuring the levels of contaminants in drinking water and determining compliance with national primary drinking water regulations. The Safe Drinking Water Act (SDWA) authorizes EPA to approve the use of alternative testing methods through publication in the Federal Register. EPA is using this streamlined authority to make 84 additional methods available for analyzing drinking water samples. This expedited approach provides public water systems, laboratories, and primacy agencies with more timely access to new measurement techniques and greater flexibility in the selection of analytical methods, thereby reducing monitoring costs while maintaining public health protection.
NASA Astrophysics Data System (ADS)
Johnson, M. S.; Lathuilliere, M. J.; Morillas, L.; Dalmagro, H. J.; D'Acunha, B.; Kim, Y.; Suarez, A.; Couto, E. G.
2017-12-01
In this talk, we will summarize results obtained using three tropical agricultural water observatories in Guanacaste, Costa Rica and Mato Grosso, Brazil. These flux towers and associated sensors enable detailed assessments of carbon use and water use efficiencies for crops under rain-fed and irrigated conditions. In addition to directly assessing water consumption from crops via eddy covariance, determination of water footprints and water use efficiencies using sensors and integrating it with remotely sensed data make it possible to (i) evaluate and compare different irrigation systems used in the study regions (drip, pivot and flood irrigation), (ii) assess the effect of irrigation over the local water balance to identify vulnerabilities associated with intensive water extraction for irrigation, and (iii) study the effect of inter-annual water availability fluctuations on crop water use. We conclude by comparing volumetric water footprints for crops, their carbon footprints, and water and carbon use efficiencies of crops produced under business-as-usual and alternative soil and water management scenarios.
Membrane Based Thermal Control Development
NASA Technical Reports Server (NTRS)
Murdoch, Karen
1997-01-01
The investigation of the feasibility of using a membrane device as a water boiler for thermal control is reported. The membrane device permits water vapor to escape to the vacuum of space but prevents the loss of liquid water. The vaporization of the water provides cooling to the water loop. This type of cooling device would have application for various types of short duration cooling needs where expenditure of water is allowed and a low pressure source is available such as in space or on a planet's surface. A variety of membrane samples, both hydrophilic and hydrophobic, were purchased to test for this thermal control application. An initial screening test determined if the membrane could pose a sufficient barrier to maintain water against vacuum. Further testing compared the heat transfer performance of those membranes that passed the screening test.
Monitoring water quality by remote sensing
NASA Technical Reports Server (NTRS)
Brown, R. L. (Principal Investigator)
1977-01-01
The author has identified the following significant results. A limited study was conducted to determine the applicability of remote sensing for evaluating water quality conditions in the San Francisco Bay and delta. Considerable supporting data were available for the study area from other than overflight sources, but short-term temporal and spatial variability precluded their use. The study results were not sufficient to shed much light on the subject, but it did appear that, with the present state of the art in image analysis and the large amount of ground truth needed, remote sensing has only limited application in monitoring water quality.
Surface-water investigations at Barrow, Alaska
Jones, Stanley H.
1972-01-01
The U.S. Public Health Service is currently developing plans for a long-term water supply and sewage treatment system for the village of Barrow, Alaska. To assist in planning, the U.S. Geological Survey was requested to initiate a cooperative streamflow data-collection program with the U.S. Public Health Service in June 1972 to determine the availability of surface water and the areal distribution of runoff in the Barrow area. This basic-data report summarizes the streamflow data collected from June 1 through July 10, 1972, at three gaging stations in the Barrow area (fig. 1) and discusses the future data-collection program.
Pellerin, Brian A.; Bergamaschi, Brian A.; Downing, Bryan D.; Saraceno, John Franco; Garrett, Jessica D.; Olsen, Lisa D.
2013-01-01
The recent commercial availability of in situ optical sensors, together with new techniques for data collection and analysis, provides the opportunity to monitor a wide range of water-quality constituents on time scales in which environmental conditions actually change. Of particular interest is the application of ultraviolet (UV) photometers for in situ determination of nitrate concentrations in rivers and streams. The variety of UV nitrate sensors currently available differ in several important ways related to instrument design that affect the accuracy of their nitrate concentration measurements in different types of natural waters. This report provides information about selection and use of UV nitrate sensors by the U.S. Geological Survey to facilitate the collection of high-quality data across studies, sites, and instrument types. For those in need of technical background and information about sensor selection, this report addresses the operating principles, key features and sensor design, sensor characterization techniques and typical interferences, and approaches for sensor deployment. For those needing information about maintaining sensor performance in the field, key sections in this report address maintenance and calibration protocols, quality-assurance techniques, and data formats and reporting. Although the focus of this report is UV nitrate sensors, many of the principles can be applied to other in situ optical sensors for water-quality studies.
Hydrology and water quality of Park Lake, south-central Wisconsin
Kammerer, P.A.
1996-01-01
Park Lake extends to the northeast from the village of Pardeeville in Columbia County (fig. 1). Local residents perceive water-quality problems in the lake that include excessive algae and aquatic plant growth. Algae and plant growth in a lake are controlled, in part, by the availability of phosphorus in the water. However, no measurements of phosphorus enter- ing the lake or of other factors that affect lake-water quality had been made, and available data on water quality were limited to 2 years of measurements at one site in the lake in 1986- 87. To obtain the data and in- formation needed to address the water-quality problems at Park Lake and to develop a management plan that would limit the input of phosphorus to the lake, the U.S. Geologi- cal Survey, in cooperation with the Park Lake Management District, studied the hydrology of the lake and collected data needed to determine sources and amount of phosphorus en- tering the lake. This Fact Sheet summarizes the results of that study. Data collected during the study were published in a separate report (Holmstrom and others, 1994, p. 70-85).
Yin, Yong-guang; Chen, Ming; Peng, Jin-feng; Liu, Jing-fu; Jiang, Gui-bin
2010-06-15
A novel and simple solid phase extraction (SPE)-high performance liquid chromatography (HPLC)-inductively coupled plasma mass spectrometry (ICP-MS) method was developed for determination of inorganic mercury (IHg), methylmercury MeHg and ethylmercury (EtHg) in water samples in the present work. The procedure involves pre-functionalization of the commercially available C18 SPE column with dithizone, loading water sample, displacement elution of mercury species by Na(2)S(2)O(3) solution, followed by HPLC-ICP-MS determination. Characterization and optimization of operation parameters of this new SPE procedure were discussed, including eluting reagent selection, concentration of eluting reagent, volume of eluting reagent, effect of NaCl and humic acid in sample matrix. At optimized conditions, the detection limits of mercury species for 100mL water sample were about 3ngL(-1) and the average recoveries were 93.7, 83.4, and 71.7% for MeHg, IHg and EtHg, respectively, by spiking 0.2microgL(-1) mercury species into de-ion water. Stability experiment reveals that both the dithizone-functionalized SPE cartridge and the mercury species incorporated were stable in the storage procedure. These results obtained demonstrate that SPE-HPLC-ICP-MS is a simple and sensitive technique for the determination of mercury species at trace level in water samples with high reproducibility and accuracy.
Determination of an organic-acid analog of DOC for use in copper toxicity studies on salmonids
DOE Office of Scientific and Technical Information (OSTI.GOV)
MacRae, R.K.; Meyer, J.S.; Hansen, J.A.
1995-12-31
Concentrations of dissolved copper in streams draining mine sites often exceed concentrations shown to cause acute and chronic mortality in salmonids. However, toxicity and impaired behaviors may be modified by dissolved organic carbon (DOC) and other inorganic components present in the site water. The effects of DOC on copper speciation, and thus bioavailability and toxicity, were determined by titrating stream waters with copper, using a cupric ion-specific electrode to detect free copper concentrations. Effects of various competing cations (e.g., Ca{sup +2}, Co{sup +2}) on copper-DOC binding were also evaluated. Titration results were evaluated using Scatchard and non-linear regression analyses tomore » quantify the strength and capacity of copper-DOC binding. Inorganic speciation was determined using the geochemical model MINEQL{sup +}. Results of these titrations indicated the presence of two or three distinct copper binding components in site water DOC. Three commercially available organic acids where then chosen to mimic the binding characteristics of natural DOC. This DOC-analog was used successfully in fish toxicity studies to evaluate the influence of DOC on copper bioavailability. Geochemical models were developed to predict copper speciation in both laboratory test waters and site waters, for any typical combination of water chemistry parameters (pH, alkalinity, [DOC], etc.). A combined interpretation of fish toxicity and modeling results indicate that some DOC-bound copper was bioavailable.« less
Stochastic Plume Simulations for the Fukushima Accident and the Deep Water Horizon Oil Spill
NASA Astrophysics Data System (ADS)
Coelho, E.; Peggion, G.; Rowley, C.; Hogan, P.
2012-04-01
The Fukushima Dai-ichi power plant suffered damage leading to radioactive contamination of coastal waters. Major issues in characterizing the extent of the affected waters were a poor knowledge of the radiation released to the coastal waters and the rather complex coastal dynamics of the region, not deterministically captured by the available prediction systems. Equivalently, during the Gulf of Mexico Deep Water Horizon oil platform accident in April 2010, significant amounts of oil and gas were released from the ocean floor. For this case, issues in mapping and predicting the extent of the affected waters in real-time were a poor knowledge of the actual amounts of oil reaching the surface and the fact that coastal dynamics over the region were not deterministically captured by the available prediction systems. To assess the ocean regions and times that were most likely affected by these accidents while capturing the above sources of uncertainty, ensembles of the Navy Coastal Ocean Model (NCOM) were configured over the two regions (NE Japan and Northern Gulf of Mexico). For the Fukushima case tracers were released on each ensemble member; their locations at each instant provided reference positions of water volumes where the signature of water released from the plant could be found. For the Deep Water Horizon oil spill case each ensemble member was coupled with a diffusion-advection solution to estimate possible scenarios of oil concentrations using perturbed estimates of the released amounts as the source terms at the surface. Stochastic plumes were then defined using a Risk Assessment Code (RAC) analysis that associates a number from 1 to 5 to each grid point, determined by the likelihood of having tracer particle within short ranges (for the Fukushima case), hence defining the high risk areas and those recommended for monitoring. For the Oil Spill case the RAC codes were determined by the likelihood of reaching oil concentrations as defined in the Bonn Agreement Oil Appearance Code. The likelihoods were taken in both cases from probability distribution functions derived from the ensemble runs. Results were compared with a control-deterministic solution and checked against available reports to assess their skill in capturing the actual observed plumes and other in-situ data, as well as their relevance for planning surveys and reconnaissance flights for both cases.
USDA-ARS?s Scientific Manuscript database
Photography has been a welcome tool in assisting to document and convey qualitative soil information. Greater availability of digital cameras with increased information storage capabilities has promoted novel uses of this technology in investigations of water movement patterns, organic matter conte...
7 CFR 1778.7 - Project priority.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 7 Agriculture 12 2010-01-01 2010-01-01 false Project priority. 1778.7 Section 1778.7 Agriculture... (CONTINUED) EMERGENCY AND IMMINENT COMMUNITY WATER ASSISTANCE GRANTS § 1778.7 Project priority. Paragraph (d... to determine the proposed project's priority for available funds. (b) State Office review. All...
7 CFR 1778.7 - Project priority.
Code of Federal Regulations, 2014 CFR
2014-01-01
... 7 Agriculture 12 2014-01-01 2013-01-01 true Project priority. 1778.7 Section 1778.7 Agriculture... (CONTINUED) EMERGENCY AND IMMINENT COMMUNITY WATER ASSISTANCE GRANTS § 1778.7 Project priority. Paragraph (d... to determine the proposed project's priority for available funds. (b) State Office review. All...
7 CFR 1778.7 - Project priority.
Code of Federal Regulations, 2012 CFR
2012-01-01
... 7 Agriculture 12 2012-01-01 2012-01-01 false Project priority. 1778.7 Section 1778.7 Agriculture... (CONTINUED) EMERGENCY AND IMMINENT COMMUNITY WATER ASSISTANCE GRANTS § 1778.7 Project priority. Paragraph (d... to determine the proposed project's priority for available funds. (b) State Office review. All...
Juhasz, Albert L; Smith, Euan; Weber, John; Rees, Matthew; Rofe, Allan; Kuchel, Tim; Sansom, Lloyd; Naidu, Ravi
2008-05-01
Considerable information is available in the literature regarding the uptake of arsenic (As) from contaminated soil and irrigation water by vegetables. However, few studies have investigated As speciation in these crops while a dearth of information is available on As bioavailability following their consumption. In this study, the concentration and speciation of As in chard, radish, lettuce and mung beans was determined following hydroponic growth of the vegetables using As-contaminated water. In addition, As bioavailability was assessed using an in vivo swine feeding assay. While As concentrations ranged from 3.0 to 84.2mg As kg(-1) (dry weight), only inorganic As (arsenite and arsenate) was detected in the edible portions of the vegetables. When As bioavailability was assessed through monitoring blood plasma As concentrations following swine consumption of As-contaminated vegetables, between 50% and 100% of the administered As dose was absorbed and entered systemic circulation. Arsenic bioavailability decreased in the order mung beans>radish>lettuce=chard.
Walia, Tarun; Abu Fanas, Salem; Akbar, Madiha; Eddin, Jamal; Adnan, Mohamad
2017-07-01
To assess fluoride concentration in drinking water which include tap water of 4 emirates - Abu Dhabi, Dubai, Sharjah and Ajman plus bottled water, commonly available soft drinks & juices in United Arab Emirates. Five different samples of tap water collected from each of the four emirates of UAE: Ajman, Sharjah, Abu Dhabi and Dubai; twenty-two brands of bottled water and fifteen brands of popular cold beverages, purchased from different supermarkets in U.A.E were tested using ion selective electrode method and the fluoride concentration was determined. The mean fluoride content of tap water samples was 0.14 mg F/L with a range of 0.04-0.3 mg F/L; with Ajman tap water samples showing the highest mean fluoride content of 0.3 mg F/L. The mean fluoride content for both bottled drinking water and beverages was 0.07 mg F/L with a range of 0.02-0.50 mg F/L and 0.04-0.1 mg F/L respectively. Majority (68.2%) of the bottled water are produced locally within U.A.E while a few (31.8%) are imported. The tap water, bottled water and beverages available in U.A.E show varying concentrations of fluoride, however none showed the optimal level necessary to prevent dental caries. Dental professionals in U.A.E should be aware of the fluoride concentrations before prescribing fluoride supplements to children.
Sources of drinking water in a pediatric population.
Jadav, Urvi G; Acharya, Bhavini S; Velasquez, Gisela M; Vance, Bradley J; Tate, Robert H; Quock, Ryan L
2014-01-01
The purpose of this study was to determine the primary sources of water used for consumption and cooking by the patients of a university-based pediatric dental practice. A simple, prewritten questionnaire-consisting of seven questions and available in English and Spanish-was conducted verbally with the caregivers of 123 pediatric patients during a designated timeframe. Analysis of responses included descriptive statistics and a chi-square test for a single proportion. Nonfiltered tap water accounted for the primary drinking water source in only 10 percent of the respondents. Firty-two percent of the respondents selected bottled water as the primary source of drinking water, and 24 percent selected vended water stations as a primary drinking water source. Nonfiltered tap water was much more likely to be utilized in cooking (58 percent). The majority of the patients in this study's pediatric dental practice do not consume fluoridated tap water. With the vast majority of the patients primarily consuming bottled or vended water, these patients are likely missing out on the caries-protective effects of water fluoridation.
Optimization of planting pattern plan in Logung irrigation area using linear program
NASA Astrophysics Data System (ADS)
Wardoyo, Wasis; Setyono
2018-03-01
Logung irrigation area is located in Kudus Regency, Central Java Province, Indonesia. Irrigation area with 2810 Ha of extent is getting water supply from Logung dam. Yet, the utilization of water at Logung dam is not optimal and the distribution of water is still not evenly distributed. Therefore, this study will discuss about the optimization of irrigation water utilization based on the beginning of plant season. This optimization begins with the analysis of hydrology, climatology and river discharge in order to determine the irrigation water needs. After determining irrigation water needs, six alternatives of planting patterns with the different early planting periods, i.e. 1st November, 2nd November, 3rd November, 1st December, 2nd December, and 3rd December with the planting pattern of rice-secondary crop-sugarcane is introduced. It is continued by the analysis of water distribution conducted using linear program assisted by POM-Quantity method for Windows 3 with the reliable discharge limit and the available land area. Output of this calculation are to determine the land area that can be planted based on the type of plant and growing season, and to obtaine the profits of harvest yields. Based on the optimum area of each plant species with 6 alternatives, the most optimum area was obtained at the early planting periods on 3rd December with the production profit of Rp 113.397.338.854,- with the planting pattern of rice / beans / sugarcane-rice / beans / sugarcane-beans / sugarcane.
How Conjunctive Use of Surface and Ground Water could Increase Resiliency in US?
NASA Astrophysics Data System (ADS)
Josset, L.; Rising, J. A.; Russo, T. A.; Troy, T. J.; Lall, U.; Allaire, M.
2016-12-01
Optimized management practices are crucial to ensuring water availability in the future. However this presents a tremendous challenge due to the many functions of water: water is not only central for our survival as drinking water or for irrigation, but it is also valued for industrial and recreational use. Sources of water meeting these needs range from rain water harvesting to reservoirs, water reuse, groundwater abstraction and desalination. A global conjunctive management approach is thus necessary to develop sustainable practices as all sectors are strongly coupled. Policy-makers and researchers have identified pluralism in water sources as a key solution to reach water security. We propose a novel approach to sustainable water management that accounts for multiple sources of water in an integrated manner. We formulate this challenge as an optimization problem where the choice of water sources is driven both by the availability of the sources and their relative cost. The results determine the optimal operational decisions for each sources (e.g. reservoirs releases, surface water withdrawals, groundwater abstraction and/or desalination water use) at each time step for a given time horizon. The physical surface and ground water systems are simulated inside the optimization by setting state equations as constraints. Additional constraints may be added to the model to represent the influence of policy decisions. To account for uncertainty in weather conditions and its impact on availability, the optimization is performed for an ensemble of climate scenarios. While many sectors and their interactions are represented, the computational cost is limited as the problem remains linear and thus enables large-scale applications and the propagation of uncertainty. The formulation is implemented within the model "America's Water Analysis, Synthesis and Heuristic", an integrated model for the conterminous US discretized at the county-scale. This enables a systematic evaluation of stresses on water resources. We explore in particular geographic and temporal trends in function of user-types to develop a better understanding of the dynamics at play. We conclude with a comparison between the optimization results and current water use to identify potential solutions to increase resiliency.
Classroom Activities about Water and Climate Change
NASA Astrophysics Data System (ADS)
Rodriguez, M.
2012-04-01
The purpose of this activity is to demonstrate practical work and experiments in the classroom, with students on Water: Water is the most neccesary Earth's resource, although it is decreasing because many human activities are changing its quality and its availability. The activity is designed in order to recreate experiments, simulations, and determine the aspects of the problematic environment currently plaguing our planet, especially those related to water and climate change. The selected activities have to be easy to make, and easy to understand. Each activity will be illustrated, explained and described using pictures and short texts, so teachers could replay them in their classroom. 1. Simulation of the Ocean Water Currents Convection to understand the heat distribution in our planet. 2. Ocean Water Stratification According to Water Salinity. We can understand the behaviour of water when we mix water from different densities 3. Melting of the Arctic and Antarctic Polar Caps. In this experiment, we can see the consequences of changing environment and climate conditions as it pertains to ice and our polar ice caps. We want to show the different behaviours of continental and floating ice and to evaluate the consequences of their melting. 4. Detecting water pollution. Here, we can analyse some water patterns and get to know the existence or absence of pollutants in the water, as well as learning how to determine its pH level, hardness, nitrogen composition, bacteria content and more. 5. Creating a home treatment. We show the necessity to preserve the water quality through a suitable treatment.
Habitat availability vs. flow rate for the Pecos River, Part 1 : Depth and velocity availability.
DOE Office of Scientific and Technical Information (OSTI.GOV)
James, Scott Carlton; Schaub, Edward F.; Jepsen, Richard Alan
2004-02-01
The waters of the Pecos River in New Mexico must be delivered to three primary users: (1) The Pecos River Compact: each year a percentage of water from natural river flow must be delivered to Texas; (2) Agriculture: Carlsbad Irrigation District has a storage and diversion right and Fort Sumner Irrigation District has a direct flow diversion right; and, (3) Endangered Species Act: an as yet unspecified amount of water is to support Pecos Bluntnose Shiner Minnow habitat within and along the Pecos River. Currently, the United States Department of Interior Bureau of Reclamation, the New Mexico Interstate Stream Commission,more » and the United States Department of the Interior Fish and Wildlife Service are studying the Pecos Bluntnose Shiner Minnow habitat preference. Preliminary work by Fish and Wildlife personnel in the critical habitat suggest that water depth and water velocity are key parameters defining minnow habitat preference. However, river flows that provide adequate preferred habitat to support this species have yet to be determined. Because there is a limited amount of water in the Pecos River and its reservoirs, it is critical to allocate water efficiently such that habitat is maintained, while honoring commitments to agriculture and to the Pecos River Compact. This study identifies the relationship between Pecos River flow rates in cubic feet per second (cfs) and water depth and water velocity.« less
Glacier loss and hydro-social risks in the Peruvian Andes
NASA Astrophysics Data System (ADS)
Mark, Bryan G.; French, Adam; Baraer, Michel; Carey, Mark; Bury, Jeffrey; Young, Kenneth R.; Polk, Molly H.; Wigmore, Oliver; Lagos, Pablo; Crumley, Ryan; McKenzie, Jeffrey M.; Lautz, Laura
2017-12-01
Accelerating glacier recession in tropical highlands and in the Peruvian Andes specifically is a manifestation of global climate change that is influencing the hydrologic cycle and impacting water resources across a range of socio-environmental systems. Despite predictions regarding the negative effects of long-term glacier decline on water availability, many uncertainties remain regarding the timing and variability of hydrologic changes and their impacts. To improve context-specific understandings of the effects of climate change and glacial melt on water resources in the tropical Andes, this article synthesizes results from long-term transdisciplinary research with new findings from two glacierized Peruvian watersheds to develop and apply a multi-level conceptual framework focused on the coupled biophysical and social determinants of water access and hydro-social risks in these settings. The framework identifies several interacting variables-hydrologic transformation, land cover change, perceptions of water availability, water use and infrastructure in local and regional economies, and water rights and governance-to broadly assess how glacier change is embedded with social risks and vulnerability across diverse water uses and sectors. The primary focus is on the Santa River watershed draining the Cordillera Blanca to the Pacific. Additional analysis of hydrologic change and water access in the geographically distinct Shullcas River watershed draining the Huaytapallana massif towards the city of Huancayo further illuminates the heterogeneous character of hydrologic risk and vulnerability in the Andes.
NASA Astrophysics Data System (ADS)
Guenette, Kris; Hernandez-Ramirez, Guillermo
2017-04-01
Achieving resiliency in agroecosystems may be accomplished through the incorporation of contemporary management systems and the diversification of crop rotations with pulse crops, such as controlled traffic farming (CTF) and faba beans (Vicia faba L.). As these practices become more common in the Canadian Prairies, it is imperative to have a well-rounded understanding of how faba beans interact with the soil-plant-atmosphere continuum in conditions found in contemporary management systems. Simulated field conditions emulated soil compaction found in both the trafficked and un-trafficked areas of a CTF system, in which the presence of high water availability was shown to offset the negative results of large applications of compactive effort. Furthermore, low water availability exacerbated differences in plant responses between compaction treatments. The simulated treatment of 1.2 gcm-3 coupled with high water content yielded the most optimal results for most measured parameters, with a contrasting detrimental treatment of 1.4 gcm-3 at low water availability. The simulated field conditions were further bridged through an analysis of two commercial sites in Alberta, Canada that compared both trafficked and un-trafficked soil properties. Soil properties such as available nitrogen (AN), pH, soil total nitrogen (STN), soil organic carbon (SOC), bulk density, macroporosity, soil quality S-Index, plant available water capacity (PAWC) and unsaturated hydraulic conductivity (Km) were analysed and compared among trafficked and un-trafficked areas. The measured soil physical and hydraulic properties of bulk density, macroporosity, S-Index, PAWC and Km were shown to be heavily influenced by the CTF traffic regime, while soil nutrient properties of AN, pH, STN SOC were determined to be dependent on both management and landscape features.
Hayden, Brian; Harrod, Chris; Kahilaineni, Kimmo K
2014-02-01
Climate change is increasing ambient temperatures in Arctic and subarctic regions, facilitating latitudinal range expansions of freshwater fishes adapted to warmer water temperatures. The relative roles of resource availability and interspecific interactions between resident and invading species in determining the outcomes of such expansions has not been adequately evaluated. Ecological interactions between a cool-water adapted fish, the perch (Perca fluviatilis), and the cold-water adapted European whitefish (Coregonus lavaretus), were studied in both shallow and deep lakes with fish communities dominated by (1) monomorphic whitefish, (2) monomorphic whitefish and perch, and (3) polymorphic whitefish and perch. A combination of stomach content, stable-isotope, and invertebrate prey availability data were used to identify resource use and niche overlap among perch, the trophic generalist large sparsely rakered (LSR) whitefish morph, and the pelagic specialist densely rakered (DR) whitefish morph in 10 subarctic lakes at the contemporary distribution limit of perch in northern Scandinavia. Perch utilized its putative preferred littoral niche in all lakes. LSR whitefish utilized both littoral and pelagic resources in monomorphic whitefish-dominated lakes. When found in sympatry with perch, LSR whitefish exclusively utilized pelagic prey in deep lakes, but displayed niche overlap with perch in shallow littoral lakes. DR whitefish was a specialist zooplanktivore, relegating LSR whitefish from pelagic habitats, leading to an increase in niche overlap between LSR whitefish and perch in deep lakes. Our results highlight how resource availability (lake depth and fish community) governs ecological interactions between native and invading species, leading to different outcomes even at the same latitudes. These findings suggest that lake morphometry and fish community structure data should be included in bioclimate envelope-based models of species distribution shifts following predicted climate change.
SSME environment database development
NASA Technical Reports Server (NTRS)
Reardon, John
1987-01-01
The internal environment of the Space Shuttle Main Engine (SSME) is being determined from hot firings of the prototype engines and from model tests using either air or water as the test fluid. The objectives are to develop a database system to facilitate management and analysis of test measurements and results, to enter available data into the the database, and to analyze available data to establish conventions and procedures to provide consistency in data normalization and configuration geometry references.
The Impact Of Snow Melt On Surface Runoff Of Sava River In Slovenia
NASA Astrophysics Data System (ADS)
Horvat, A.; Brilly, M.; Vidmar, A.; Kobold, M.
2009-04-01
Snow is a type of precipitation in the form of crystalline water ice, consisting of a multitude of snowflakes that fall from clouds. Snow remains on the ground until it melts or sublimates. Spring snow melt is a major source of water supply to areas in temperate zones near mountains that catch and hold winter snow, especially those with a prolonged dry summer. In such places, water equivalent is of great interest to water managers wishing to predict spring runoff and the water supply of cities downstream. In temperate zone like in Slovenia the snow melts in the spring and contributes certain amount of water to surface flow. This amount of water can be great and can cause serious floods in case of fast snow melt. For this reason we tried to determine the influence of snow melt on the largest river basin in Slovenia - Sava River basin, on surface runoff. We would like to find out if snow melt in Slovenian Alps can cause spring floods and how serious it can be. First of all we studied the caracteristics of Sava River basin - geology, hydrology, clima, relief and snow conditions in details for each subbasin. Furtermore we focused on snow and described the snow phenomenom in Slovenia, detailed on Sava River basin. We collected all available data on snow - snow water equivalent and snow depth. Snow water equivalent is a much more useful measurement to hydrologists than snow depth, as the density of cool freshly fallen snow widely varies. New snow commonly has a density of between 5% and 15% of water. But unfortunately there is not a lot of available data of SWE available for Slovenia. Later on we compared the data of snow depth and river runoff for some of the 40 winter seasons. Finally we analyzed the use of satellite images for Slovenia to determine the snow cover for hydrology reason. We concluded that snow melt in Slovenia does not have a greater influence on Sava River flow. The snow cover in Alps can melt fast due to higher temperatures but the water distributes and runs off slowly and does not cause floods. About use of satellite images we concluded that first of all, weather is unfavorable - lots of cloudiness in winter, and furthermore a grater part of land is covered by forest which prevents to see the snow cover on image clearly.
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.
Characterization of shallow ocean sediments using the airborne electromagnetic method
NASA Technical Reports Server (NTRS)
Won, I. J.; Smits, K.
1986-01-01
Experimental airborne electromagnetic (AEM) survey data collected in Cape Cod Bay are used to derive continuous profiles of water depth, electrical depth, water conductivity, and bottom sediment conductivity. Through a few well-known empirical relationships, the conductivities are used, in turn, to derive density, porosity, sound speed, and acoustic reflectivity of the ocean bottom. A commercially available Dighem III AEM system was used for the survey without any significant modification. The helicopter-borne system operated at 385 and 7200 Hz; both were in a horizontal coplanar configuration. The interpreted profiles show good agreement with available ground truth data. Where no such data are available, the results appear to be very reasonable. Compared with the shipborne electrode array method, the AEM method can determine the necessary parameters at a much higher speed with a better lateral resolution over a wide range of water depths from 0 to perhaps 100 m. The bottom sediment conductivity that can be measured by the AEM method is closely related to physical properties of sediments, such as porosity, density, sound speed, and, indirectly, sediment types that might carry broad implications for various offshore activities.
Spitz, Frederick J.
2009-01-01
Critical Area 1 in east-central New Jersey was mandated in the early 1980s to address large drawdowns caused by increases in groundwater withdrawals. The aquifers involved include the Englishtown aquifer system, Wenonah-Mount Laurel aquifer, and the Upper and Middle Potomac-Raritan-Magothy aquifers. Groundwater levels recovered as a result of mandated cutbacks in withdrawals that began in the late 1980s. Subsequent increased demand for water has necessitated an analysis to determine the effects of full-allocation withdrawals, which supplements an optimization analysis done previously. A steady-state regional groundwater flow model is used to evaluate the effects of 2003 withdrawals and full-allocation withdrawals (7.3 million gallons per day greater than for 2003) on simulated water-levels. Simulation results indicate that the range of available withdrawals greater than full-allocation withdrawals is likely between 0 and 12 million gallons per day. The estimated range of available withdrawals is based on: (1) an examination of hydraulic-heads resulting from each of the two simulations, (2) an examination of differences in heads between these two simulations, (3) a comparison of simulated heads from each of the two simulations with the estimated location of salty groundwater, and (4) a comparison of simulated 2003 water levels to observed 2003 water levels. The results of the simulations also indicate that obtaining most of the available water would require varying the distribution of withdrawals and (or) relaxing the mandated hydrologic constraints used to protect the water supply.
NASA Astrophysics Data System (ADS)
Drezner, Taly Dawn
2013-02-01
Species distributions reflect limiting factors, particularly near the margins of their range where density and abundance decrease as environmental factors decrease or increase to non-optimal conditions. I test whether the keystone saguaro cactus (Carnegiea gigantea), a shallow-rooted species, is indeed distributed disproportionately in areas of concentrated drainage (runnels) in a water-limited population. Carnegiea and a common nurse were sampled at a marginal site in and out of areas with concentrated surface water and chi-square analysis was used to determine the pattern of distribution. In this study I found that, surprisingly, near the hot, water-limited edge of their range, C. gigantea are found significantly less often in areas where more water would be available to them. For example, while only 20% of nurses were on interfluves, half of Carnegiea protégé were there. One possible explanation is that the subsequent redistribution of seeds by water away from preferred microsites may be important in shaping the final pattern of successful establishment. The shallow-rooted Carnegiea relies entirely on surface water for its moisture; it is thus paradoxical that the surface water so fundamentally essential to its survival throughout its life appears to hinder its establishment in precisely those sites where the greatest surface water would be available, particularly near the water-limited edge of its range.
Several approaches are available for evaluating adverse effects in near coastal ecosystems. These range from performing toxicity tests with individual organisms on water column and sediment samples to conducting macrofaunal compositional analyses on pelagic and benthic communiti...
Quantifying plant age and available water effects on soybean leaf conductance
USDA-ARS?s Scientific Manuscript database
In this study, we present data characterizing the effects of soil moisture levels on total leaf conductance for two distinct determinate soybean (Glycine max (L.) Merr.) genotypes and subsequently use these data to formulate and validate a model that characterizes total leaf conductance. Conductanc...
Zeolite Soil Application Method Affects Inorganic Nitrogen, Moisture, and Corn Growth
USDA-ARS?s Scientific Manuscript database
Adoption of new management techniques which improve soil water storage and soil nitrogen plant availability yet limit nitrogen leaching may help improve environmental quality. A benchtop study was conducted to determine the influence of a single urea fertilizer rate (224 kilograms of Nitrogen per ...
Water quality assessment of the River Nile system: an overview.
Wahaab, Rifaat A; Badawy, Mohamed I
2004-03-01
The main objective of the present article is to assess and evaluate the characteristics of the Nile water system, and identify the major sources of pollution and its environmental and health consequences. The article is also aimed to highlight the importance of water management via re-use and recycle of treated effluents for industrial purpose and for cultivation of desert land. An intensive effort was made by the authors to collect, assess and compile the available data about the River Nile. Physico-chemical analyses were conducted to check the validity of the collected data. For the determination of micro-pollutants, Gas Chromatography (GC) and High Performance Liquid Chromatography (HPLC) were used. Heavy metals were also determined to investigate the level of industrial pollution in the river system. The available data revealed that the river receives a large quantity of industrial, agriculture and domestic wastewater. It is worth mentioning that the river is still able to recover in virtually all the locations, with very little exception. This is due to the high dilution ratio. The collected data confirmed the presence of high concentrations of chromium and manganese in all sediment samples. The residues of organo-chlorine insecticides were detected in virtually all locations. However, the levels of such residues are usually below the limit set by the WHO for use as drinking water. The most polluted lakes are Lake Maryut and Lake Manzala. Groundwater pollution is closely related to adjacent (polluted) surface waters. High concentrations of nutrients, E. coli, sulfur, heavy metals, etc. have been observed in the shallow groundwater, largely surpassing WHO standards for drinking water use. A regular and continuous monitoring scheme shall be developed for the River Nile system. The environmental law shall be enforced to prohibit the discharge of wastewater (agricultural, domestic or industrial) to River Nile system.
Hawthorne, Steven B; Poppendieck, Dustin G; Grabanski, Carol B; Loehr, Raymond C
2002-11-15
Soil and sediment samples from oil gas (OG) and coal gas (CG) manufactured gas plant (MGP) sites were selected to represent a range of PAH concentrations (150-40,000 mg/kg) and sample matrix compositions. Samples varied from vegetated soils to lampblack soot and had carbon contents from 3 to 87 wt %. SFE desorption (120 min) and water/XAD2 desorption (120 days) curves were determined and fit with a simple two-site model to determine the rapid-released fraction (F) for PAHs ranging from naphthalene to benzo[ghi]perylene. F values varied greatly among the samples, from ca. 10% to >90% for the two- and three-ring PAHs and from <1% to ca. 50% for the five- and six-ring PAHs. Release rates did not correlate with sample matrix characteristics including PAH concentrations, elemental composition (C, H, N, S), or "hard" and "softs" organic carbon, indicating that PAH release cannot easily be estimated on the basis of sample matrix composition. Fvalues for CG site samples obtained with SFE and water desorption agreed well (linear correlation coefficient, r2 = 0.87, slope = 0.93), but SFE yielded higher F values for the OG samples. These behaviors were attributed to the stronger ability of carbon dioxide than water to desorb PAHs from the highly aromatic (hard) carbon of the OG matrixes, while carbon dioxide and water showed similar abilities to desorb PAHs from the more polar (soft) carbon of the CG samples. The combined SFE and water desorption approaches should improve the understanding of PAH sequestration and release from contaminated soils and sediments and provide the basis for subsequent studies using the same samples to compare PAH release with PAH availability to earthworms.
Water management can reinforce plant competition in salt-affected semi-arid wetlands
NASA Astrophysics Data System (ADS)
Coletti, Janaine Z.; Vogwill, Ryan; Hipsey, Matthew R.
2017-09-01
The diversity of vegetation in semi-arid, ephemeral wetlands is determined by niche availability and species competition, both of which are influenced by changes in water availability and salinity. Here, we hypothesise that ignoring physiological differences and competition between species when managing wetland hydrologic regimes can lead to a decrease in vegetation diversity, even when the overall wetland carrying capacity is improved. Using an ecohydrological model capable of resolving water-vegetation-salt feedbacks, we investigate why water surface and groundwater management interventions to combat vegetation decline have been more beneficial to Casuarina obesa than to Melaleuca strobophylla, the co-dominant tree species in Lake Toolibin, a salt-affected wetland in Western Australia. The simulations reveal that in trying to reduce the negative effect of salinity, the management interventions have created an environment favouring C. obesa by intensifying the climate-induced trend that the wetland has been experiencing of lower water availability and higher root-zone salinity. By testing alternative scenarios, we show that interventions that improve M. strobophylla biomass are possible by promoting hydrologic conditions that are less specific to the niche requirements of C. obesa. Modelling uncertainties were explored via a Markov Chain Monte Carlo (MCMC) algorithm. Overall, the study demonstrates the importance of including species differentiation and competition in ecohydrological models that form the basis for wetland management.
Dieter, Cheryl A.; Fleck, William B.
2008-01-01
Potentiometric surfaces in the Piney Point-Nanjemoy, Aquia, and Upper Patapsco aquifers have declined from 1950 through 2000 throughout southern Maryland. In the vicinity of Lexington Park, Maryland, the potentiometric surface in the Aquia aquifer in 2000 was as much as 170 feet below sea level, approximately 150 feet lower than estimated pre-pumping levels before 1940. At the present rate, the water levels will have declined to the regulatory allowable maximum of 80 percent of available drawdown in the Aquia aquifer by about 2050. The effect of the withdrawals from these aquifers by the Naval Air Station Patuxent River and surrounding users on the declining potentiometric surface has raised concern for future availability of ground water. Growth at Naval Air Station Patuxent River may increase withdrawals, resulting in further drawdown. A ground-water-flow model, combined with optimization modeling, was used to develop withdrawal scenarios that minimize the effects (drawdown) of hypothetical future withdrawals. A three-dimensional finite-difference ground-water-flow model was developed to simulate the ground-water-flow system in the Piney Point-Nanjemoy, Aquia, and Upper Patapsco aquifers beneath the Naval Air Station Patuxent River. Transient and steady-state conditions were simulated to give water-resource managers additional tools to manage the ground-water resources. The transient simulation, representing 1900 through 2002, showed that the magnitude of withdrawal has increased over that time, causing ground-water flow to change direction in some areas. The steady-state simulation was linked to an optimization model to determine optimal solutions to hypothetical water-management scenarios. Two optimization scenarios were evaluated. The first scenario was designed to determine the optimal pumping rates for wells screened in the Aquia aquifer within three supply groups to meet a 25-percent increase in withdrawal demands, while minimizing the drawdown at a control location. The resulting optimal solution showed that pumping six wells above the rate required for maintenance produced the least amount of drawdown in the local potentiometric surface. The second hypothetical scenario was designed to determine the optimal location for an additional well in the Aquia aquifer in the northeastern part of the main air station. The additional well was needed to meet an increase in withdrawal of 43,000 cubic feet per day. The optimization model determined the optimal location for the new well, out of a possible 10 locations, while minimizing drawdown at control nodes located outside the western boundary of the main air station. The optimal location is about 1,500 feet to the east-northeast of the existing well.
Navigating the Clean Water Act: Connectivity and Legal Protection of Aquatic Resources
NASA Astrophysics Data System (ADS)
Downing, D. M.; Raanan Kiperwas, H.
2012-12-01
The Clean Water Act is the principal federal law protecting the integrity of waters in the United States (e.g., rivers, streams, wetlands, lakes). Clean Water Act protection after U.S. Supreme Court decisions in Solid Waste Agency of Northern Cook County (SWANCC) (2001) and Rapanos (2006) is determined based on case-by-case analyses of connections among waters. Determining a water's status as a "water of the US" protected by the Act typically requires data and analysis of characteristics such as its flow, and biological and chemical relationships with downstream waters. When such data is not available, the Clean Water Act might not protect the quality and integrity of the water in question. This raises a number of legal and technical challenges for implementation, as well as questions regarding underlying aquatic sciences. In addition, many of the terms used by the court are not fully consistent with similar scientific terms, potentially causing confusion among policymakers and scientists alike. This presentation will discuss the Clean Water Act, and how currently its protections for aquatic resources are dependent on connectivity with larger downstream waters, particularly for those that do not flow perennially. The presentation will focus on the role science has played in forming and informing policy making, areas where science and policy may not be fully consistent, areas where research is still needed, and provide a policy "dictionary" for scientists interested in working on this evolving issue.
Majuru, Batsirai; Jagals, Paul; Hunter, Paul R
2012-10-01
Although a number of studies have reported on water supply improvements, few have simultaneously taken into account the reliability of the water services. The study aimed to assess whether upgrading water supply systems in small rural communities improved access, availability and potability of water by assessing the water services against selected benchmarks from the World Health Organisation and South African Department of Water Affairs, and to determine the impact of unreliability on the services. These benchmarks were applied in three rural communities in Limpopo, South Africa where rudimentary water supply services were being upgraded to basic services. Data were collected through structured interviews, observations and measurement, and multi-level linear regression models were used to assess the impact of water service upgrades on key outcome measures of distance to source, daily per capita water quantity and Escherichia coli count. When the basic system was operational, 72% of households met the minimum benchmarks for distance and water quantity, but only 8% met both enhanced benchmarks. During non-operational periods of the basic service, daily per capita water consumption decreased by 5.19l (p<0.001, 95% CI 4.06-6.31) and distances to water sources were 639 m further (p ≤ 0.001, 95% CI 560-718). Although both rudimentary and basic systems delivered water that met potability criteria at the sources, the quality of stored water sampled in the home was still unacceptable throughout the various service levels. These results show that basic water services can make substantial improvements to water access, availability, potability, but only if such services are reliable. Copyright © 2012 Elsevier B.V. All rights reserved.
Weaver, J. Curtis
2015-03-12
In 2013, the U.S. Geological Survey, in cooperation with the North Carolina Division of Water Resources, compiled updated low-flow characteristics and flow-duration statistics for selected continuous-record streamgages in North Carolina. The compilation of updated streamflow statistics provides regulators and planners with relevant hydrologic information reflective of the recent droughts, which can be used to better manage the quantity and quality of streams in North Carolina. Streamflow records available through the 2012 water year1 were used to determine the annual (based on climatic year2) and winter 7-day, 10-year (7Q10, W7Q10) low-flow discharges, the 30-day, 2-year (30Q2) low-flow discharge, and the 7-day, 2-year (7Q2) low-flow discharge. Consequently, streamflow records available through March 31, 2012 (or the 2011 climatic year) were used to determine the updated low-flow characteristics. Low-flow characteristics were published for 177 unregulated sites, 56 regulated sites, and 33 sites known or considered to be affected by varying degrees of minor regulation and (or) diversions upstream from the streamgages (266 sites total). The updated 7Q10 discharges were compared for 63 streamgages across North Carolina where (1) long-term streamflow record consisted of 30 or more climatic years of data available as of the 1998 climatic year, and (2) streamflows were not known to be regulated. The 7Q10 discharges did not change for 3 sites, whereas increases and decreases were noted at 5 and 55 sites, respectively. Positive changes (increases) ranged from 4.3 percent (site 362) to 34.1 percent (site 112) with a median of 13.2 percent. Negative percentage changes (decreases) ranged from –3.3 percent (site 514) to –80.0 percent (site 308) with a median of –22.2 percent. The median percentage change for all 63 streamgages was –18.4 percent. Streamflow statistics determined as a part of this compilation included minimum, mean, maximum, and flow-duration statistics of daily mean discharges for categorical periods. Flow-duration statistics based on the daily mean discharge records were compiled in this study for the 5th, 10th, 25th, 50th, 75th, 90th, and 95th percentiles. Flow-duration statistics were determined for each complete water year of record at a streamgage as well as the available period of record (or selected periods if flows were regulated) and selected seasonal, monthly, and calendar day periods. In addition to the streamflow statistics compiled for each of the water years, the number of days the daily mean discharge was at or below the 10th percentile was summed for each water year as well as the number of events during the water year when streamflow was consistently at or below the 10th percentile. All low-flow characteristics for the streamgages were added into the StreamStatsDB, which is a database accessible to users through the recently released USGS StreamStats application for North Carolina. The minimum, mean, maximum, and flow-duration statistics of daily mean discharges based on the available (or selected if regulated flows) period of record were updated in the North Carolina StreamStatsDB. However, for the selected seasonal, monthly, calendar day, and annual water year periods, tab-delimited American Standard Code for Information Interchange (ASCII) tables of the streamflow statistics are available online to users from a link provided in the StreamStats application. 1The annual period from October 1 through September 30, designated by the year in which the period ends. 2The annual period from April 1 through March 31, designated by the year in which the period begins.
2013-01-01
Oil biodegradation by native bacteria is one of the most important natural processes that can attenuate the environmental impacts of marine oil spills. Existing models for oil biodegradation kinetics are mostly for dissolved oil. This work developed a new mathematical model for the biodegradation of oil droplets and applied the model to estimate the time scale for oil biodegradation under conditions relevant to the Deepwater Horizon oil spill in the Gulf of Mexico. In the model, oil is composed of droplets of various sizes following the gamma function distribution. Each oil droplet shrinks during the microbe-mediated degradation at the oil-water interface. Using our developed model, we find that the degradation of oil droplets typically goes through two stages. The first stage is characterized by microbial activity unlimited by oil-water interface with higher biodegradation rates than that of the dissolved oil. The second stage is governed by the availability of the oil-water interface, which results in much slower rates than that of soluble oil. As a result, compared to that of the dissolved oil, the degradation of oil droplets typically starts faster and then quickly slows down, ultimately reaching a smaller percentage of degraded oil in longer time. The availability of the water-oil interface plays a key role in determining the rates and extent of degradation. We find that several parameters control biodegradation rates, including size distribution of oil droplets, initial microbial concentrations, initial oil concentration and composition. Under conditions relevant to the Deepwater Horizon spill, we find that the size distribution of oil droplets (mean and coefficient of variance) is the most important parameter because it determines the availability of the oil-water interface. Smaller oil droplets with larger variance leads to faster and larger extent of degradation. The developed model will be useful for evaluating transport and fate of spilled oil, different remediation strategies, and risk assessment. PMID:24138161
Determination of irrigation pumpage in parts of Kearny and Finney Counties, southwestern Kansas
Lindgren, R.J.
1982-01-01
Irrigation pumpage was determined for parts of Kearny and Finney Counties in Southwestern Kansas using crop-acreage data and consumptive, irrigation-water requirements. Irrigated acreages for 1974-80 were compiled for wheat, grain sorghum, corn, and alfalfa using records from the U.S. Agricultural Stabilization and Conservation Service. Consumptive-irrigation requirements were computed using a soil-moisture model. The model tabulated monthly soil-moisture and crop-water demand for various crops and computed the volume of irrigation water needed to maintain the available moisture at 50% for loamy soils or at 60% for sandy soils. Irrigated acres in the study area increased from 265,000 acres during 1974 to 321,000 acres during 1980. Irrigation pumpage increased from 584,000 acre-feet during 1974 to 738,000 acre-feet during 1980. Decreased consumptive-irrigation requirements during 1979 resulted in a comparatively small irrigation-pumpage estimate of 458,000 acre-feet. (USGS)
NASA Astrophysics Data System (ADS)
Campos-Gaytan, J. R.; Herrera-Oliva, C. S.
2013-05-01
In this study was analyzed through a regional groundwater flow model the effects on groundwater levels caused by the application of different future groundwater management scenarios (2007-2025) at the Guadalupe Valley, in Baja California, Mexico. Among these studied alternatives are those scenarios designed in order to evaluate the possible effects generated for the groundwater artificial recharge in order to satisfy a future water demand with an extraction volume considered as sustainable. The State of Baja California has been subject to an increment of the agricultural, urban and industrials activities, implicating a growing water-demand. However, the State is characterized by its semiarid-climate with low surface water availability; therefore, has resulted in an extensive use of groundwater in local aquifer. Water level measurements indicate there has been a decline in water levels in the Guadalupe Valley for the past 30 years. The Guadalupe Valley aquifer represents one the major sources of water supply in Ensenada region. It supplies about 25% of the water distributed by the public water supplier at the city of Ensenada and in addition constitutes the main water resource for the local wine industries. Artificially recharging the groundwater system is one water resource option available to the study zone, in response to increasing water demand. The existing water supply system for the Guadalupe Valley and the city of Ensenada is limited since water use demand periods in 5 to 10 years or less will require the construction of additional facilities. To prepare for this short-term demand, one option available to water managers is to bring up to approximately 3.0 Mm3/year of treated water of the city of Ensenada into the valley during the low-demand winter months, artificially recharge the groundwater system, and withdraw the water to meet the summer demands. A 2- Dimensional groundwater flow was used to evaluate the effects of the groundwater artificial recharge. Artificial recharge is feasible and is one water resource technique available to meet an increasing water demand; therefore, the final objective was to estimate the response of the groundwater system to the possible development of a system for artificial recharge of the aquifer. Based on the analysis of the groundwater management alternatives it was determined a groundwater withdrawal which ensures a sustainable management of the aquifer, in order to maintain a sustainable extraction volume and to reduce the water table depletion.
Methods to estimate irrigated reference crop evapotranspiration - a review.
Kumar, R; Jat, M K; Shankar, V
2012-01-01
Efficient water management of crops requires accurate irrigation scheduling which, in turn, requires the accurate measurement of crop water requirement. Irrigation is applied to replenish depleted moisture for optimum plant growth. Reference evapotranspiration plays an important role for the determination of water requirements for crops and irrigation scheduling. Various models/approaches varying from empirical to physically base distributed are available for the estimation of reference evapotranspiration. Mathematical models are useful tools to estimate the evapotranspiration and water requirement of crops, which is essential information required to design or choose best water management practices. In this paper the most commonly used models/approaches, which are suitable for the estimation of daily water requirement for agricultural crops grown in different agro-climatic regions, are reviewed. Further, an effort has been made to compare the accuracy of various widely used methods under different climatic conditions.
Li, Tiejun; Guo, Yuanming; Hu, Hongmei; Zhang, Xiaoning; Jin, Yanjian; Zhang, Xiaojun; Zhang, Yurong
2016-01-01
A simple, efficient, solvent-free, and commercial readily available approach for determination of five volatile chlorinated hydrocarbons in water samples using the static headspace sampling and gas chromatography with electron capture detection has been described. The proposed static headspace sampling method was initially optimized and the optimum experimental conditions found were 10 mL water sample containing 20% w/v sodium chloride placed in a 20 mL vial and stirred at 50ºC for 20 min. The linearity of the method was in the range of 1.2-240 μg/L for dichloromethane, 0.2-40 μg/L for trichloromethane, 0.005-1 μg/L for perchloromethane, 0.025-5 μg/L for trichloroethylene, and 0.01-2 μg/L for perchloroethylene, with coefficients of determination ranging between 0.9979 and 0.9990. The limits of detection were in the low μg/L level, ranging between 0.001 and 0.3 μg/L. The relative recoveries of spiked five volatile chlorinated hydrocarbons with external calibration method at different concentration levels in pure, tap, sea water of Jiaojiang Estuary, and sea water of waters of Xiaomendao were in the range of 91-116, 96-105, 86-112, and 80-111%, respectively, and with relative standard deviations of 1.9-3.6, 2.3-3.5, 1.5-2.7, and 2.3-3.7% (n = 5), respectively. The performance of the proposed method was compared with traditional liquid-liquid extraction on the real water samples (i.e., pure, tap, and sea water, etc.) and comparable efficiencies were obtained. It is concluded that this method can be successfully applied for the determination of volatile chlorinated hydrocarbons in different water samples. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Water storage capacity, stemflow and water funneling in Mediterranean shrubs
NASA Astrophysics Data System (ADS)
Garcia-Estringana, P.; Alonso-Blázquez, N.; Alegre, J.
2010-08-01
SummaryTo predict water losses and other hydrological and ecological features of a given vegetation, its water storage capacity and stemflow need to be accurately determined. Vast areas of the Mediterranean region are occupied by shrublands yet there is scarce data available on their rainwater interception capacity. In this study, simulated rainfall tests were conducted in controlled conditions on nine Mediterranean shrubs of varying anatomic and morphological features to determine water storage capacity, stemflow and the funneling ratio. After assessing correlations between these hydrological variables and the biometric characteristics of the shrubs, we compared two methods of determining storage capacity: rainfall simulation and immersion. Mean water storage capacity was 1.02 mm (0.35-3.24 mm), stemflow was 16% (3.8-26.4%) and the funneling ratio was 104 (30-260). Per unit biomass, mean storage capacity was 0.66 ml g -1 and ranged from 0.23 ml g -1 for Cistus ladanifer to 2.26 ml g -1 for Lavandula latifolia. Despite their small size, shrubs may generate high water losses to the atmosphere when they form dense communities and this can have a significant impact in regions where water is scarce. When considered the whole shrubs in absolute terms (ml per plant), water storage capacity and stemflow were correlated to biomass and the dendrometric characteristics of the shrubs, yet in relative terms (expressed per surface area unit or as %), anatomic features such as pubescence, branch rigidity or leaf insertion angle emerged as determining factors. The use of a simple procedure to assess storage capacity was inefficient. The immersion method underestimated storage capacity to a different extent for each species. Some shrubs returned high stemflow values typical of their adaptation to the semiarid climate. In contrast, other shrubs seem to have structures that promote stemflow yet have developed other drought-adaptation mechanisms. In this report, we discuss the ecological and hydrological significance of stemflow and the funneling ratio.
Beverage osmolality as a marker for maintaining appropriate body hydration.
Sadowska, Anna; Świderski, Franciszek; Rakowska, Rita; Waszkiewicz-Robak, Bożena; Żebrowska-Krasuska, Małgorzata; Dybkowska, Ewa
2017-01-01
Osmolalities can be useful markers for determining whether given beverages are suited for maintaining an adequate hydration of the body. Losing 2% of body water relative to body mass reduces the efficiency of body function when undertaking physical effort by around 20%. Deficiencies in water intakes approaching 5-8% of body mass, double the impairment to the body’s physical and mental functioning, whereas at a level of 10% the body becomes incapable of performing any sort of physical effort. For such reasons the body’s hydration status is vital to its functioning. To asses osmolalities as measured in various types of commercially available mineral waters and non-alcoholic beverages containing different amounts of extracts. Test materials were commercially available mineral waters (of low, medium and high mineral content) along with juices, nectars and drinks that are isotonic, energising and those described as being ‘light’ and sparkling. Osmolality was measured by the 800CL Osmometer instrument from TridentMed whilst the RL-type refractometer was used for determining extract values. Isotonic drinks were found to have the same osmotic pressures as bodily fluids at 275 – 295 mOsm/kg water. The osmotic pressure in mineral waters depended on the extent of mineralisation and ranged from 13 mOsm / kg water (low mineral content) to 119 mOsm/kg water (high mineral content). Low osmolalities were also found in ‘light’ drinks (from 29.3 to 34 mOsm/kg water). Juices, nectars, energising drinks and colas typically have high sugar contents and have high osmolalities ranging 492 – 784 mOsm / kg water. Statistical analysis demonstrated significant associations (p < 0.05) between osmolalities and extract content in beverages as well as between osmolalities and mineral content in mineral waters. Upon factor analysis, it was possible to group the tested drinks according to similar osmolalities and extract content. Osmolalities measured in beverages are a marker that permits drinks to be classified into groups according to their tonicity and their ability to ensure that the body is properly hydrated; this becoming vital in cases when the body requires rapid body fluid replenishment.
Pan-European household and industrial water demand: regional relevant estimations
NASA Astrophysics Data System (ADS)
Bernhard, Jeroen; Reynaud, Arnaud; de Roo, Ad
2016-04-01
Sustainable water management is of high importance to provide adequate quality and quantity of water to European households, industries and agriculture. Especially since demographic, economic and climate changes are expected to increase competition for water between these sectors in the future. A shortage of water implies a reduction in welfare of households or damage to economic sectors. This socio-economic component should be incorporated into the decision-making process when developing water allocation schemes, requiring detailed water use information and cost/benefit functions. We now present the results of our study which is focused at providing regionally relevant pan-European water demand and cost-benefit estimations for the household and industry sector. We gathered consistent data on water consumption, water prices and other relevant variables at the highest spatial detail available from national statistical offices and other organizational bodies. This database provides the most detailed up to date picture of present water use and water prices across Europe. The use of homogeneous data allowed us to compare regions and analyze spatial patterns. We applied econometric methods to determine the main determinants of water demand and make a monetary valuation of water for both the domestic and industry sector. This monetary valuation is important to allow water allocation based on economic damage estimates. We also attempted to estimate how population growth, as well as socio-economic and climatic changes impact future water demand up to 2050 using a homogeneous method for all countries. European projections for the identified major drivers of water demand were used to simulate future conditions. Subsequently, water demand functions were applied to estimate future water use and potential economic damage caused by water shortages. We present our results while also providing some estimation of the uncertainty of our predictions.
NASA Astrophysics Data System (ADS)
Malek, Keyvan; Adam, Jennifer C.; Stöckle, Claudio O.; Peters, R. Troy
2018-06-01
Irrigation efficiency plays an important role in agricultural productivity; it affects farm-scale water demand, and the partitioning of irrigation losses into evaporative and non-evaporative components. This partitioning determines return flow generation and thus affects water availability. Over the last two decades, hydrologic and agricultural research communities have significantly improved our understanding of the impacts of climate change on water availability and food productivity. However, the impacts of climate change on the efficiency of irrigation systems, particularly on the partitioning between evaporative and non-evaporative losses, have received little attention. In this study, we incorporated a process-based irrigation module into a coupled hydrologic/agricultural modeling framework (VIC-CropSyst). To understand how climate change may impact irrigation losses, we applied VIC-CropSyst over the Yakima River basin, an important agricultural region in Washington State, U.S. We compared the historical period of 1980-2010 to an ensemble of ten projections of climate for two future periods: 2030-2060 and 2060-2090. Results averaged over the watershed showed that a 9% increase in evaporative losses will be compensated by a reduction of non-evaporative losses. Therefore, overall changes in future efficiency are negligible (-0.4%) while the Evaporative Loss Ratio (ELR) (defined as the ratio of evaporative to non-evaporative irrigation losses) is enhanced by 10%. This higher ELR is associated with a reduction in return flows, thus negatively impacting downstream water availability. Results also indicate that the impact of climate change on irrigation losses depend on irrigation type and climate scenarios.
Folberth, Christian; Suhadolc, Metka; Scherb, Hagen; Munch, Jean Charles; Schroll, Reiner
2009-10-01
Two approaches to determine pesticide (bio-)availability in soils (i) batch experiments with "extraction with an excess of water" (EEW) and (ii) the recently introduced "soil pore water (PW) extraction" of pesticide incubated soil samples have been compared with regard to the sorption behavior of the model compound isoproturon in soils. A significant correlation between TOC and adsorbed pesticide amount was found when using the EEW approach. In contrast, there was no correlation between TOC and adsorbed isoproturon when using the in situ PW extraction method. Furthermore, sorption was higher at all concentrations in the EEW method when comparing the distribution coefficients (K(d)) for both methods. Over all, sorption in incubated soil samples at an identical water tension (-15 kPa) and soil density (1.3 g cm(-3)) appears to be controlled by a complex combination of sorption driving soil parameters. Isoproturon bioavailability was found to be governed in different soils by binding strength and availability of sorption sites as well as water content, whereas the dominance of either one of these factors seems to depend on the individual composition and characteristics of the respective soil sample. Using multiple linear regression analysis we obtained furthermore indications that the soil pore structure is affected by the EEW method due to disaggregation, resulting in a higher availability of pesticide sorption sites than in undisturbed soil samples. Therefore, it can be concluded that isoproturon sorption is overestimated when using the EEW method, which should be taken into account when using data from this approach or similar batch techniques for risk assessment analysis.
A review on water pricing problem for sustainable water resource
NASA Astrophysics Data System (ADS)
Hek, Tan Kim; Ramli, Mohammad Fadzli; Iryanto
2017-05-01
A report that presented at the World Forum II at The Hague in March 2000, said that it would be water crisis around the world and some countries will be lack of water in 2025, as a result of global studies. Inefficient using of water and considering water as free goods which means it can be used as much as we want without any lost. Thus, it causes wasteful consumption and low public awareness in using water without effort to preserve and conserve the water resources. In addition, the excessive exploitation of ground water for industrial facilities also leads to declining of available freshwater. Therefore, this paper reviews some problems arise all over the world regarding to improper and improving management, policies and methods to determine the optimum model of freshwater price in order to avoid its wasteful thus ensuring its sustainability. In this paper, we also proposed a preliminary model of water pricing represents a case of Medan, North Sumatera, Indonesia.
Evaluation of infiltration for the determination of palms water needs
NASA Astrophysics Data System (ADS)
Benlarbi, Dalila; Boutaoutaou, Djamel; Saggaï, Sofiane
2018-05-01
In arid climate conditions, irrigation water requirements increase, but available water resources are limited. And therefore the Saharan regions, large consumers of water can be seriously threatened if they do not make the necessary to become as parsimonious as allow the irrigation techniques whose technological aspect on their improvement has been privileged until now but all the problems are not solved. The objective of this work is to know the process of infiltration of water in the soil, i.e.: to try to determine exactly its value with obtaining the best combination (flow of entry, board length and irrigation time) in order to have a more or less uniform distribution in the soil and especially by avoiding significant water losses that would cause rise in the water table. The infiltration will allow us to calculate at any point the dose of water received that we will compare with the needs of the date palm. For this purpose; we varied the input flow for a constant board length. Then we varied the board length for a constant input rate. In both cases we varied the irrigation time according to the water requirements of the date palm. The flow remains of course constant during the entire feeding period. This study is primarily experimental and aims to meet practical applications but not immediately because it is necessary to continue the experiments with several other combinations to achieve practical results.
Igbeneghu, Oluwatoyin A; Lamikanra, Adebayo
2014-11-28
The upsurge in the demand for bottled water has prompted the interest of many manufacturers in the production of bottled water and very many water bottling companies are therefore involved in its production. These range from large scale multinational companies to medium scale business enterprises, institutional and government business investment companies as well as small scale entrepreneurs. There is however little information on the comparative quality of bottled water brands produced by different classes of water bottling companies in Nigeria. This study was undertaken to determine the bacteriological quality of brands of bottled water available to consumers in Ile-Ife. Forty-three samples of bottled water comprising of three batches each of thirteen bottled water brands and two batches of two brands were purchased and analyzed for total bacterial count, presence of coliform and the presence of other bacterial indicators of drinking water quality. Only 67.4% of the water samples representing the products of 10 companies or 66.7% of the brands had heterotrophic counts within the acceptable limits. Coliforms present in 100 ml of water were detected in 26.7% of the bottled water brands. Other indicator organisms detected included Staphylococci isolated from 27.9% of the samples (33.3% of the brands) and specifically Staphylococcus aureus found in four brands constituting 14% of the samples. Pseudomonas strains were consistently detected in consecutive batches of three brands of the water samples. Bottled water samples produced by the large scale multinational producers were of acceptable bacteriological quality unlike those produced by most small companies. There is need for a greater control of water bottling processes carried out by commercial bottled water producers in Nigeria.
Research on water shortage risks and countermeasures in North China
NASA Astrophysics Data System (ADS)
Cheng, Yuxiang; Fang, Wenxuan; Wu, Ziqin
2017-05-01
In the paper, a grey forecasting model and a population growth model are established for forecasting water resources supply and demand situation in the region, and evaluating the scarcity of water resources thereof in order to solve the problem of water shortage in North China. A concrete plan for alleviating water resources pressure is proposed with AHP as basis, thereby discussing the feasibility of the plan. Firstly, water resources supply and demand in the future 15 years are predicted. There are four sources for the demand of water resources mainly: industry, agriculture, ecology and resident living. Main supply sources include surface water and underground water resources. A grey forecasting method is adopted for predicting in the paper aiming at water resources demands since industrial, agricultural and ecological water consumption data have excessive decision factors and the correlation is relatively fuzzy. Since residents' water consumption is determined by per capita water consumption and local population, a logistic growth model is adopted to forecast the population. The grey forecasting method is used for predicting per capita water consumption, and total water demand can be obtained finally. International calculation standards are adopted as reference aiming at water supply. The grey forecasting method is adopted for forecasting surface water quantity and underground water quantity, and water resources supply is obtained finally. Per capita water availability in the region is calculated by comparing the water resources supply and demand. Results show that per capita water availability in the region is only 283 cubic meters this year, people live in serious water shortage region, who will suffer from water shortage state for long time. Then, sensitivity analysis is applied for model test. The test result is excellent, and the prediction results are more accurate. In the paper, the following measures are proposed for improving water resources condition in the region according to prediction results, such as construction of reservoirs, sewage treatment, water diversion project and other measures. A detailed water supply plan is formulated. Water supply weights of all measures are determined according to the AHP model. Solution is sought after original models are improved. Results show that water resources quantity per capita will be up to 2170 cubic meters or so this year, people suffer from moderate water shortage in the region, which can meet people's life needs and economic development needs basically. In addition, water resources quantity per capita is increased year by year, and it can reach mild water shortage level after 2030. In a word, local water resources dilemma can be effectively solved by the plan actually, and thoughts can be provided for decision makers.
Quantifying water flow and retention in an unsaturated fracture-facial domain
Nimmo, John R.; Malek-Mohammadi, Siamak
2015-01-01
Hydrologically significant flow and storage of water occur in macropores and fractures that are only partially filled. To accommodate such processes in flow models, we propose a three-domain framework. Two of the domains correspond to water flow and water storage in a fracture-facial region, in addition to the third domain of matrix water. The fracture-facial region, typically within a fraction of a millimeter of the fracture wall, includes a flowing phase whose fullness is determined by the availability and flux of preferentially flowing water, and a static storage portion whose fullness is determined by the local matric potential. The flow domain can be modeled with the source-responsive preferential flow model, and the roughness-storage domain can be modeled with capillary relations applied on the fracture-facial area. The matrix domain is treated using traditional unsaturated flow theory. We tested the model with application to the hydrology of the Chalk formation in southern England, coherently linking hydrologic information including recharge estimates, streamflow, water table fluctuation, imaging by electron microscopy, and surface roughness. The quantitative consistency of the three-domain matrix-microcavity-film model with this body of diverse data supports the hypothesized distinctions and active mechanisms of the three domains and establishes the usefulness of this framework.
Pfeifer, O; Lohmann, U; Ballschmiter, K
2001-11-01
Halogenated methyl-phenyl ethers (methoxybenzenes, anisoles) are ubiquitous organics in the environment although they are not produced in industrial quantities. Modelling the fate of organic pollutants such as halogenated anisoles requires a knowledge of the fundamental physico-chemical properties of these compounds. The isomer-specific separation and detection of 60 of the 134 possible congeners allowing an environmental fingerprinting are reported in this study. The vapor pressure p0(L) of more than 60 and further physico-chemical properties of 26 available congeners are given. Vapor pressures p0(L), water solubilities S(L)W, and n-octanol/water partition coefficients Kow were determined by capillary HR-GC (High Resolution Gas Chromatography) on a non-polar phase and by RP-HPLC (Reversed Phase High Performance Liquid Chromatography) on a C18 phase with chlorobenzenes as reference standards. From these experimental data the Henry's law constants H, and the gas/water Kgw and gas/n-octanol Kgo partition coefficients were calculated. We found that vapor pressures, water solubilities, and n-octanol/water partition coefficients of the halogenated anisoles are close to those of the chlorobenzenes. A similar environmental fate of both groups can, therefore, be predicted.
Kemble, N.E.; Dwyer, F.J.; Ingersoll, C.G.; Dawson, T.D.; Norberg-King, T. J.
1999-01-01
A method is described for preparing formulated sediments for use intoxicity testing. Ingredients used to prepare formulated sediments included commercially available silt, clay, sand, humic acid, dolomite, and α-cellulose (as a source of organic carbon). α-Cellulose was selected as the source of organic carbon because it is commercially available, consistent from batch to batch, and low in contaminant concentrations. The tolerance of freshwater test organisms to formulated sediments for use as control materials in whole-sediment toxicity testing was evaluated. Sediment exposures were conducted for 10 d with the amphipod Hyalella azteca, the midges Chironomus riparius and C. tentans, and the oligochaete Lumbriculus variegatus and for 28 d with H. azteca. Responses of organisms in formulated sediments was compared with a field-collected control sediment that has routinely been used to determine test acceptability. Tolerance of organisms to formulated sediments was evaluated by determining responses to varying levels of α-cellulose, to varying levels of grain size, to evaluation of different food types, or to evaluation of different sources of overlying water. In the 10-d exposures, survival of organisms exposed to the formulated sediments routinely met or exceeded the responses of test organisms exposed to the control sediment and routinely met test acceptability criteria required in standard methods. Growth of amphipods and oligochaetes in 10-d exposures with formulated sediment was often less than growth of organisms in the field-collected control sediment. Additional research is needed, using the method employed to prepare formulated sediment, to determine if conditioning formulated sediments before starting 10-d tests would improve the growth of amphipods. In the 28-d exposures, survival of H. azteca was low when reconstituted water was used as the source of overlying water. However, when well water was used as the source of overlying water in 28-d exposures, consistent responses of amphipods were observed in both formulated and control sediments.
Review of Methods and Approaches for Deriving Numeric ...
EPA will propose numeric criteria for nitrogen/phosphorus pollution to protect estuaries, coastal areas and South Florida inland flowing waters that have been designated Class I, II and III , as well as downstream protective values (DPVs) to protect estuarine and marine waters. In accordance with the formal determination and pursuant to a subsequent consent decree, these numeric criteria are being developed to translate and implement Florida’s existing narrative nutrient criterion, to protect the designated use that Florida has previously set for these waters, at Rule 62-302.530(47)(b), F.A.C. which provides that “In no case shall nutrient concentrations of a body of water be altered so as to cause an imbalance in natural populations of aquatic flora or fauna.” Under the Clean Water Act and EPA’s implementing regulations, these numeric criteria must be based on sound scientific rationale and reflect the best available scientific knowledge. EPA has previously published a series of peer reviewed technical guidance documents to develop numeric criteria to address nitrogen/phosphorus pollution in different water body types. EPA recognizes that available and reliable data sources for use in numeric criteria development vary across estuarine and coastal waters in Florida and flowing waters in South Florida. In addition, scientifically defensible approaches for numeric criteria development have different requirements that must be taken into consider
Determinants of tree water use across a floodplain in arid, subtropical northwest Australia
NASA Astrophysics Data System (ADS)
Grierson, Pauline; McLean, Elizabeth; Iles, Jordan; Skrzypek, Grzegorz; Brand, Melinda; O'Donnell, Alison; Siebers, Andre; Dogramaci, Shawan
2017-04-01
Riparian zones of ephemeral streams in hot arid regions are subject to unpredictable and generally short-lived flood periods. However, droughts tend to be longer and more severe than floods in their ecological impact as low water availability in surficial alluvium and on the floodplain results in hydrological stress. Resolving how riparian and floodplain vegetation respond to highly variable flow regimes remains a fundamental challenge for estimating water budgets in arid regions, particularly where water tables are subject to groundwater abstraction. Here, we investigated patterns of water use by a range of tree species (Eucalyptus camaldulensis, E. victrix, Acacia citrinoviridis, A. coriacea, Hakea lorea, Atalaya hemiglauca) across a floodplain in the Pilbara region of northwest Australia and assessed vegetation responsiveness to both temporal and spatial variation in water supply. We sought to disentangle the varying contributions of soil water, groundwater and surface water to tree water use to determine the ecological implications of changes in hydrologic connectivity resulting from both seasonal water deficits and anthropogenic management. Diurnal and seasonal dynamics of water use were assessed using sapflux measurements coupled with observations of changing source availability. Source utilization was examined using water stable isotope compositions of xylem, soil, rain, surface water and groundwater. Depending on distance from the stream channel and time since last rainfall, we found that small trees were primarily accessing shallow soil water of meteoric origin while larger eucalypts accessed water deeper in the profile (either stored soil water or groundwater), especially as surface soils dried out. However, tree species were highly variable in their diurnal patterns of water use,including some evidence of nocturnal sapflux in A. coriacea adjacent to streams. Sapflux rates also varied almost four-fold among species but generally declined with increasing depth to watertable i.e on to the floodplain. Ongoing studies are investigating how hyporheic zones expand and contract in response to episodic flows and vegetation water use in order to develop an integrated 3D hydrological/ecohydrological model to explore relationships between regional and local water tables, surface water flows, and evaporative and evapotranspiration fluxes. New insights into the biological, ecological and physical processes that control the flow of water between the biotic and abiotic compartments of ephemeral streams will be used to target specific aspects of flow regimes that are critical to maintaining riparian and floodplain ecosystems in dryland environments, particularly where streams are subject to altered hydrology.
The interaction of genotype and environment determines variation in the maize kernal ionome
USDA-ARS?s Scientific Manuscript database
Plants obtain soil-resident elements that support growth and metabolism via water-mediated flow due to transpiration and active transport processes. The availability of elements in the environment can interact with the genetic capacity of the organism to modulate element uptake through plastic adapt...
Forest canopy structural properties. Chapter 14
Marie-Louise Smith; Jeanne Anderson; Matthew Fladeland
2008-01-01
The forest canopy is the interface between the land and the atmosphere, fixing atmospheric carbon into biomass and releasing oxygen and water. The arrangement of individual trees, differences in species morphology, the availability of light and soil nutrients, and many other factors determine canopy structure. Overviews of approaches for basic measurements of canopy...
Single Laboratory Comparison of Host-Specific PCR Assays for the Detection of Bovine Fecal Pollution
There are numerous PCR-based methods available to detect bovine fecal pollution in ambient waters. Each method targets a different gene and microorganism leading to differences in method performance, making it difficult to determine which approach is most suitable for field appl...
USDA-ARS?s Scientific Manuscript database
Precipitation limits primary production by affecting soil moisture, and soil type interacts with soil moisture to determine soil water availability to plants. We used ALMANAC, a process-based model, to simulate switchgrass (Panicum virgatum var. Alamo) biomass production in Central Texas under thre...
AN OVERVIEW OF PARTITIONING AND BIOAVAILABILITY OF PAHS IN SEDIMENTS AND SOILS
Understanding and predicting any adverse effects of PAHs depends on generating a reliable measure or estimate of how much PAH is available for uptake. Simply knowing the total amount of PAH in soil, water or sediment is insufficient for determining whether or not these compounds ...
How to Determine Polyetheylene Glycol 1,000 Content in Treated Wood
Howard N. Rosen
1975-01-01
An experimental technique using water extraction for evaluation of the content of ployethylene glycol of molecular weight 1,000 in wood where the ovendry weight of the untreated wood is not available was shown to be applicable for PEG-treated black oak and yellow-poplar.
Petkewich, Matthew D.; Conrads, Paul
2013-01-01
The Everglades Depth Estimation Network is an integrated network of real-time water-level gaging stations, a ground-elevation model, and a water-surface elevation model designed to provide scientists, engineers, and water-resource managers with water-level and water-depth information (1991-2013) for the entire freshwater portion of the Greater Everglades. The U.S. Geological Survey Greater Everglades Priority Ecosystems Science provides support for the Everglades Depth Estimation Network in order for the Network to provide quality-assured monitoring data for the U.S. Army Corps of Engineers Comprehensive Everglades Restoration Plan. In a previous study, water-level estimation equations were developed to fill in missing data to increase the accuracy of the daily water-surface elevation model. During this study, those equations were updated because of the addition and removal of water-level gaging stations, the consistent use of water-level data relative to the North American Vertical Datum of 1988, and availability of recent data (March 1, 2006, to September 30, 2011). Up to three linear regression equations were developed for each station by using three different input stations to minimize the occurrences of missing data for an input station. Of the 667 water-level estimation equations developed to fill missing data at 223 stations, more than 72 percent of the equations have coefficients of determination greater than 0.90, and 97 percent have coefficients of determination greater than 0.70.
NASA Astrophysics Data System (ADS)
Barthel, Roland; Nickel, Darla; Meleg, Alejandro; Trifkovic, Aleksandar; Braun, Juergen
Within the framework of the research project ‘GLOWA-Danube’, a model of the water supply sector has been developed. GLOWA-Danube investigates long-term changes in the water cycle of the Upper Danube river basin in light of global change. For this purpose, the decision support system DANUBIA, comprising 15 fully coupled models, has been developed. Within DANUBIA the water supply model (‘WaterSupply’) forms the link between various physical models determining water quality and availability and several socio-economic models determining water consumption and demand. Having a central focus on public drinking water supply, its purpose is to correctly simulate the present day system of water extraction and distribution and the related costs, but also to allow meaningful response to possible future changes of boundary conditions, first and foremost changes in water demand or water availability and quality. Response mechanisms are also envisioned for changes in political and economic boundary conditions, and advances in technology. The model will be used locate critical regions which could experience water stress in the future, but does not aim to find the appropriate solutions or to predict the optimal organisation of water supply in the Danube Basin under such changing conditions. In the object-oriented model structure, both water supply companies (WSC) and communities are represented by main classes. Both classes have a limited view and knowledge of their environment. A community knows where and how much water is consumed and from which WSC it is served. A WSC possesses information regarding extraction sites and water rights, raw water quality and potential collaborating WSC. The WSC can perform actions that are different from ‘business as usual’. These deviations from their usual behaviour can be interpreted by decision makers but should not be regarded as a replacement for the decision-making process itself. The model is conceptualised using object-oriented concepts of the Unified Modelling Language (UML) and is implemented in JAVA. This short overview is meant to answer key questions such as why and how WaterSupply was implemented, what is unique and new about the model and what are the general lessons learned and the added value with regard to integrated modelling on a river basin scale. It is obvious that in the attempt to answer these questions it is not possible to satisfy experts from all the relevant related fields, which include computer sciences, economy, behavioural science and not least water supply engineering and hydrology.
Simulation of a double-effect LiBr/H{sub 2}O absorption cooling system
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wardono, B.; Nelson, R.
1996-10-01
Since commercially-available, double-effect, absorption cooling systems give relatively high performance for using solar energy or other medium-temperature sources, their performance was simulated and studied. To evaluate the cooling system performance, two objective functions were established: the system performance (COP) and the system cost. The system cost was used as the objective function to determine the optimum design of the system, while the COP was used to evaluate the effects of each variable on the system performance. The system optimization shows that there is an economic optimum heat-transfer area for each heat exchanger. Further study shows that this is a globalmore » minimum cost of the system. The best COPs that could be achieved by changing the heat-transfer areas and the inlet hot water temperature vary between 1.4 and 1.5. Higher COPs of approximately 1.6 were achieved if higher chilled water inlet temperatures or lower cooling water temperatures are used. These conditions are not desirable since higher chilled water inlet temperatures are not useful for cooling, and lower cooling water inlet temperatures are not usually available.« less
Martinez-Sena, María Teresa; de la Guardia, Miguel; Esteve-Turrillas, Francesc A; Armenta, Sergio
2017-12-15
A new analytical procedure, based on liquid chromatography with diode array and fluorescence detection, has been proposed for the determination of bioactive compounds in vegetables and spices after hard cap espresso extraction. This novel extraction system has been tested for the determination of capsaicin and dihydrocapsaicin from fresh chilli and sweet pepper, piperine from ground pepper, curcumin from turmeric and curry, and myristicin from nutmeg. Extraction efficiency was evaluated by using acetonitrile:water and ethanol:water mixtures. The proposed method allows the extraction of samples with 100mL of 60% (v/v) ethanol in water. The obtained limits of quantification for the proposed procedure ranged from 0.07 to 0.30mgg -1 and results were statistically comparable with those obtained by ultrasound assisted extraction. Hard cap espresso machines offer a fast, effective and quantitative tool for the extraction of bioactive compounds from food samples with an extraction time lower than 30s, using a global available and low cost equipment. Copyright © 2017 Elsevier Ltd. All rights reserved.
Sensitivity of Water Scarcity Events to ENSO-Driven Climate Variability at the Global Scale
NASA Technical Reports Server (NTRS)
Veldkamp, T. I. E.; Eisner, S.; Wada, Y.; Aerts, J. C. J. H.; Ward, P. J.
2015-01-01
Globally, freshwater shortage is one of the most dangerous risks for society. Changing hydro-climatic and socioeconomic conditions have aggravated water scarcity over the past decades. A wide range of studies show that water scarcity will intensify in the future, as a result of both increased consumptive water use and, in some regions, climate change. Although it is well-known that El Niño- Southern Oscillation (ENSO) affects patterns of precipitation and drought at global and regional scales, little attention has yet been paid to the impacts of climate variability on water scarcity conditions, despite its importance for adaptation planning. Therefore, we present the first global-scale sensitivity assessment of water scarcity to ENSO, the most dominant signal of climate variability. We show that over the time period 1961-2010, both water availability and water scarcity conditions are significantly correlated with ENSO-driven climate variability over a large proportion of the global land area (> 28.1 %); an area inhabited by more than 31.4% of the global population. We also found, however, that climate variability alone is often not enough to trigger the actual incidence of water scarcity events. The sensitivity of a region to water scarcity events, expressed in terms of land area or population exposed, is determined by both hydro-climatic and socioeconomic conditions. Currently, the population actually impacted by water scarcity events consists of 39.6% (CTA: consumption-to-availability ratio) and 41.1% (WCI: water crowding index) of the global population, whilst only 11.4% (CTA) and 15.9% (WCI) of the global population is at the same time living in areas sensitive to ENSO-driven climate variability. These results are contrasted, however, by differences in growth rates found under changing socioeconomic conditions, which are relatively high in regions exposed to water scarcity events. Given the correlations found between ENSO and water availability and scarcity conditions, and the relative developments of water scarcity impacts under changing socioeconomic conditions, we suggest that there is potential for ENSO-based adaptation and risk reduction that could be facilitated by more research on this emerging topic.
NASA Astrophysics Data System (ADS)
Castro-Camus, E.; Palomar, M.; Covarrubias, A. A.
2013-10-01
The declining water availability for agriculture is becoming problematic for many countries. Therefore the study of plants under water restriction is acquiring extraordinary importance. Botanists currently follow the dehydration of plants comparing the fresh and dry weight of excised organs, or measuring their osmotic or water potentials; these are destructive methods inappropriate for in-vivo determination of plants' hydration dynamics. Water is opaque in the terahertz band, while dehydrated biological tissues are partially transparent. We used terahertz spectroscopy to study the water dynamics of Arabidopsis thaliana by comparing the dehydration kinetics of leaves from plants under well-irrigated and water deficit conditions. We also present measurements of the effect of dark-light cycles and abscisic acid on its water dynamics. The measurements we present provide a new perspective on the water dynamics of plants under different external stimuli and confirm that terahertz can be an excellent non-contact probe of in-vivo tissue hydration.
Water demand management research: A psychological perspective
NASA Astrophysics Data System (ADS)
Russell, Sally; Fielding, Kelly
2010-05-01
The availability of fresh water for human consumption is a critical global issue and one that will be exacerbated by the impacts of climate change. Water demand management has an important role to play in reducing the vulnerability of freshwater supplies to climate change impacts. In this paper, we argue that the field of psychology and environmental psychology in particular can make a vital contribution in understanding further the drivers of residential water demand. A growing body of literature in environmental psychology has examined the determinants of water conservation behavior, and this research has many potential applications for water demand policy. In this paper we offer a review of current psychological research that examines the five broad causes of residential water conservation behaviors: attitudes, beliefs, habits or routines, personal capabilities, and contextual factors. We assess how psychologists have studied water conservation behavior to date, identify shortcomings, and indicate how this research can be used to further promote residential water conservation and to inform evidence-based policy and practice.
Bioavailability of butachlor and myclobutanil residues in soil to earthworms.
Yu, Y L; Wu, X M; Li, S N; Fang, H; Tan, Y J; Yu, J Q
2005-05-01
To establish chemical extraction procedures for predicting bioavailability of butachlor and myclobutanil in soil, several solvent systems, including methanol, methanol-water (9:1), methanol-water (1:1), acetone-water (5:3), petroleum ether and water, were assessed for their feasibility in determining extractability of the target compounds from soil samples. Experimental data showed that the extractability of butachlor and myclobutanil by the solvents was well linearly correlated with their bioavailability to Eisenia foetida and Allolobophora caliginosa, indicating that these extraction procedures may be efficient for predicting bioavailability of the two pesticides. The concentrations of the pesticides accumulated in E. foetida and A. caliginosa varied with species, suggesting that the availability of the soil-sequestered pesticide is a species-dependent process.
NASA Astrophysics Data System (ADS)
Hernández J., P.; Befani M., R.; Boschetti N., G.; Quintero C., E.; Díaz E., L.; Lado, M.; Paz-González, A.
2015-04-01
The Avellaneda District, located in northeastern of Santa Fe Province, Argentina, has an average annual rainfall of 1250 mm per year, but with a high variability in their seasonal distribution. Generally, the occurrence of precipitation in winter is low, while summer droughts are frequent. The yearly hydrological cycle shows a water deficit, given that the annual potential evapotranspiration is estimated at 1330 mm. Field crops such as soybean, corn, sunflower and cotton, which are affected by water stress during their critical growth periods, are dominant in this area. Therefore, a supplemental irrigation project has been developed in order to identify workable solutions. This project pumps water from Paraná River to provide a water supply to the target area under irrigation. A pressurized irrigation system operating on demand provides water to a network of channels, which in turn deliver water to farms. The scheduled surface of irrigation is 8800 hectares. The maximum flow rate was designed to be 8.25 m3/second. The soils have been classified as Aquic Argiudolls in areas of very gentle slopes, and Vertic Argiudolls in flat and concave reliefs; neither salinity nor excess sodium affect the soils of the study are. The objective of this study was to provide a quantitative data set to manage the irrigation project, through the determination of available water (AW), easily available water (EAw) and optimal water range (or interval) of the soil horizons. The study has been conducted in a text area of 1500 hectares in surface. Five soil profiles were sampled to determine physical properties (structure stability, effective root depth, infiltration, bulk density, penetration resistance and water holding capacity), chemical properties (pH, cation exchange capacity, base saturation, salinity, and sodium content ) and morphological characteristics of the successive horizons. Also several environmental characteristics were evaluated, including: climate, topographic conditions, relief, general and slope position, erosion, natural vegetation and agricultural crops. Indeed the computed available water (AW) content and easily available water (EAw) content values depended on bulk density, field capacity and permanent wilting point, but also they were affected by the soil penetration resistance measured to a depth of 80 cm; this parameter limits the extent of the soil volume explored by plant roots and therefore EAw content. Moreover, soil penetration resistance enables to take into account the concept of optimal water interval, which indicates how soil compaction limits the levels of easily available water that really can be extracted by the crop. The estimated values of EAw water ranged from 74 to 133 mm for the profiles studies. When including the concept of mechanical resistance to penetration to obtain the value of the optimal water interval, the above values decreased, ranging between 34 and 57 mm; this was mainly explained on the basis of the true depth of exploration by plant roots of the soil profiles. Based on the recorded values of the soil mechanical resistance to penetration, it was concluded that sunflower and corn crops will be mostly affected on their growth and root development. Subsequently, and for a maximum consumptive use of 10 mm/day, the commonly used irrigation interval of 13 days, should decrease to 6 days, if the new methodology is used i.e. if the limitations of soil depth exploration by crop roots are taken into account. This result is consistent with those from current practices under non irrigated conditions, where it has been shown that crop yields are affected by water shortage provided that an important precipitation doesn't occur among such interval.
Control of abusive water addition to Octopus vulgaris with non-destructive methods.
Mendes, Rogério; Schimmer, Ove; Vieira, Helena; Pereira, João; Teixeira, Bárbara
2018-01-01
Abusive water addition to octopus has evidenced the need for quick non-destructive methods for product qualification in the industry and control of fresh commercial products in markets. Electric conductivity (EC)/pH and dielectric property measurements were selected to detect water uptake in octopus. A significant EC decrease was determined after soaking octopus in freshwater for 4 h. EC reflected the water uptake of octopus and the correspondent concentration decrease of available ions in the interstitial fluid. Significant correlations were determined between octopus water uptake, EC (R = -0.940) and moisture/protein (M/P) ratio (R = 0.923) changes. Seasonal and spatial variation in proximate composition did not introduce any uncertainty in EC discrimination of freshwater tampering. Immersion in 5 g L -1 sodium tripolyphosphate (STPP) increased EC to a value similar to control octopus. EC false negatives resulting from the use of additives (STPP and citric acid) were eliminated with the additional determination of pH. Octopus soaked in freshwater, STPP and citric acid can also be clearly discriminated from untreated samples (control) and also from frozen (thawed) ones using the dielectric properties. No significant differences in the dielectric property scores were found between octopus sizes or geographical locations. Simultaneous EC/pH or dielectric property measurements can be used in a handheld device for non-destructive water addition detection in octopus. M/P ratio can be used as a reference destructive method. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.
Determinants of Post-fire Water Quality in the Western United States
NASA Astrophysics Data System (ADS)
Rust, A.; Saxe, S.; Dolan, F.; Hogue, T. S.; McCray, J. E.
2015-12-01
Large wildfires are becoming increasingly common in the Western United States. Wildfires that consume greater than twenty percent of the watershed impact river water quality. The surface waters of the arid West are limited and in demand by the aquatic ecosystems, irrigated agriculture, and the region's growing human population. A range of studies, typically focused on individual fires, have observed mobilization of contaminants, nutrients (including nitrates), and sediments into receiving streams. Post-fire metal concentrations have also been observed to increase when fires were located in streams close to urban centers. The objective of this work was to assemble an extensive historical water quality database through data mining from federal, state and local agencies into a fire-database. Data from previous studies on individual fires by the co-authors was also included. The fire-database includes observations of water quality, discharge, geospatial and land characteristics from over 200 fire-impacted watersheds in the western U.S. since 1985. Water quality data from burn impacted watersheds was examined for trends in water quality response using statistical analysis. Watersheds where there was no change in water quality after fire were also examined to determine characteristics of the watershed that make it more resilient to fire. The ultimate goal is to evaluate trends in post-fire water quality response and identify key drivers of resiliency and post-fire response. The fire-database will eventually be publicly available.Large wildfires are becoming increasingly common in the Western United States. Wildfires that consume greater than twenty percent of the watershed impact river water quality. The surface waters of the arid West are limited and in demand by the aquatic ecosystems, irrigated agriculture, and the region's growing human population. A range of studies, typically focused on individual fires, have observed mobilization of contaminants, nutrients (including nitrates), and sediments into receiving streams. Post-fire metal concentrations have also been observed to increase when fires were located in streams close to urban centers. The objective of this work was to assemble an extensive historical water quality database through data mining from federal, state and local agencies into a fire-database. Data from previous studies on individual fires by the co-authors was also included. The fire-database includes observations of water quality, discharge, geospatial and land characteristics from over 200 fire-impacted watersheds in the western U.S. since 1985. Water quality data from burn impacted watersheds was examined for trends in water quality response using statistical analysis. Watersheds where there was no change in water quality after fire were also examined to determine characteristics of the watershed that make it more resilient to fire. The ultimate goal is to evaluate trends in post-fire water quality response and identify key drivers of resiliency and post-fire response. The fire-database will eventually be publicly available.
Availability of ground water in the Blackstone River area Rhode Island and Massachusetts
Johnston, Herbert E.; Dickerman, David C.
1974-01-01
The Blackstone River study area covers 83 square miles of northern Rhode Island and 5 square miles of adjacent Massachusetts (fig. 1). It includes parts of the Blackstone, Moshassuck, and Tenmile River basins, and a coastal area that drains to the brackish Seekonk and Providence Rivers. In Rhode Island, all or parts of the suburban towns of Cumberland, Lincoln, North Smithfield, and Smithfield and all or parts of the cities of Central Falls, East Povidence, Pawtucket, Providence, and Woonsocket are within the study area. Also included are parts of the towns Attleboro and North Attleborough in Massachusetts. In 1970, total population was about 240,000, which was equivalent to about one-fourth of the total population of Rhode Island. Fresh water usage in 1970 by public-supply systems and self-supplied industry was about 33 mgd (million gallons per day), which was equal to 22 percent of total fresh water use in Rhode Island for all purposes except generation of electric power (fig. 2). Anticipated increases in population and per capita water requirements are likely to cause the demand for water to more than double within the next 50 years. A significant part of this demand can be met from wells that tap the principal streams. This aquifer yielded an average of 10 mgd in 1970 and is capable of sustaining a much higher yield. The primary objectives of the study were to determine and map the saturated thickness and transmissivity of the stratified-drift aquifer and to assess the potential sustained yield of those parts of the aquifer favorable for large-scale development of water. A secondary objective was to describe ground-water quality and to evaluate the impact of induced infiltration of polluted stream water on the quality of native ground water. This report is based on analysis of drillers' records of more than 700 wells and borings which include 462 lithologic logs; 35 specific-capacity determinations; 12 aquifer tests, including detailed tests at two sites to determine streambed infiltration rates; chemical analyses of 92 ground-water and 15 stream-water samples; and geologic mapping. Selected base data are published in a separate (Johnston and Dickerman, in press). The authors are indebted to well drillers, especially American Drilling and Boring Company, R.E. Chapman Company, and Layne New England Company, for making their records available; to the water departments of the towns of Cumberland and Lincoln, for allowing aquifer tests of their well fields; to the Rhode Island Department of Health, for providing data on water quality and use; and to many other federal, state, and municipal agencies, companies, and individuals who supplied information. Their contributions are gratefully acknowledged.
Habitat shifts in rainbow trout: competitive influences of brown trout.
Gatz, A J; Sale, M J; Loar, J M
1987-11-01
We compared habitat use by rainbow trout sympatric (three streams) and allopatric (two streams) with brown trout to determine whether competition occurred between these two species in the southern Appalachian Mountains. We measured water depth, water velocity, substrate, distance to overhead vegetation, sunlight, and surface turbulence both where we collected trout and for the streams in general. This enabled us to separate the effects of habitat availability from possible competitive effects. The results provided strong evidence for asymmetrical interspecific competition. Habitat use varied significantly between allopatric and sympatric rainbow trout in 68% of the comparisons made. Portions of some differences refelected differences in habitats available in the several streams. However, for all habitat variables measured except sunlight, rainbow trout used their preferred habitats less in sympatry with brown trout than in allopatry if brown trout also preferred the same habitats. Multivariate analysis indicated that water velocity and its correlates (substrate particle size and surface turbulence) were the most critical habitat variables in the interaction between the species, cover in the form of shade and close overhead vegetation was second most important, and water depth was least important.
Fluoride Content of Bottled Waters in Hong Kong and Qatar.
Al-Mulla, Hessa I; Anthonappa, Robert P; King, Nigel M
2016-01-01
To determine the F concentration of bottled waters that was available in Hong Kong and Qatar. The F concentrations of bottled waters collected from Hong Kong (n=81) and Qatar (n=32) were analysed. The F ion selective electrode method was used to measure the F concentration in the samples. Three measurements were obtained for every sample to ensure reproducibility and appropriate statistical analyses were employed. Qatar group: F concentrations ranged from 0.06 ppm to 3.0 ppm with a mean value of 0.8 ppm. The F concentrations displayed on the labels of the samples (60%) were significantly lower than the measured F concentration (p < 0.0001). Hong Kong group: F concentrations ranged from 0.04 ppm to 2.52 ppm with a mean value of 0.44 ppm. The F concentrations displayed on the samples (16%) were significantly lower than the measured F concentration (p< 0.0001). Wide variations exist in the F concentration among the different brands of bottled water available in Hong Kong and Qatar. The F concentrations displayed on the labels were not consistent with the measured F concentrations.
Arihood, Leslie D.
2009-01-01
In 2005, the U.S. Geological Survey began a pilot study for the National Assessment of Water Availability and Use Program to assess the availability of water and water use in the Great Lakes Basin. Part of the study involves constructing a ground-water flow model for the Lake Michigan part of the Basin. Most ground-water flow occurs in the glacial sediments above the bedrock formations; therefore, adequate representation by the model of the horizontal and vertical hydraulic conductivity of the glacial sediments is important to the accuracy of model simulations. This work processed and analyzed well records to provide the hydrogeologic parameters of horizontal and vertical hydraulic conductivity and ground-water levels for the model layers used to simulated ground-water flow in the glacial sediments. The methods used to convert (1) lithology descriptions into assumed values of horizontal and vertical hydraulic conductivity for entire model layers, (2) aquifer-test data into point values of horizontal hydraulic conductivity, and (3) static water levels into water-level calibration data are presented. A large data set of about 458,000 well driller well logs for monitoring, observation, and water wells was available from three statewide electronic data bases to characterize hydrogeologic parameters. More than 1.8 million records of lithology from the well logs were used to create a lithologic-based representation of horizontal and vertical hydraulic conductivity of the glacial sediments. Specific-capacity data from about 292,000 well logs were converted into horizontal hydraulic conductivity values to determine specific values of horizontal hydraulic conductivity and its aerial variation. About 396,000 well logs contained data on ground-water levels that were assembled into a water-level calibration data set. A lithology-based distribution of hydraulic conductivity was created by use of a computer program to convert well-log lithology descriptions into aquifer or nonaquifer categories and to calculate equivalent horizontal and vertical hydraulic conductivities (K and KZ, respectively) for each of the glacial layers of the model. The K was based on an assumed value of 100 ft/d (feet per day) for aquifer materials and 1 ft/d for nonaquifer materials, whereas the equivalent KZ was based on an assumed value of 10 ft/d for aquifer materials and 0.001 ft/d for nonaquifer materials. These values were assumed for convenience to determine a relative contrast between aquifer and nonaquifer materials. The point values of K and KZ from wells that penetrate at least 50 percent of a model layer were interpolated into a grid of values. The K distribution was based on an inverse distance weighting equation that used an exponent of 2. The KZ distribution used inverse distance weighting with an exponent of 4 to represent the abrupt change in KZ that commonly occurs between aquifer and nonaquifer materials. The values of equivalent hydraulic conductivity for aquifer sediments needed to be adjusted to actual values in the study area for the ground-water flow modeling. The specific-capacity data (discharge, drawdown, and time data) from the well logs were input to a modified version of the Theis equation to calculate specific capacity based horizontal hydraulic conductivity values (KSC). The KSC values were used as a guide for adjusting the assumed value of 100 ft/d for aquifer deposits to actual values used in the model. Water levels from well logs were processed to improve reliability of water levels for comparison to simulated water levels in a model layer during model calibration. Water levels were interpolated by kriging to determine a composite water-level surface. The difference between the kriged surface and individual water levels was used to identify outlier water levels. Examination of the well-log lithology data in map form revealed that the data were not only useful for model input, but also were useful for understanding th
Levels and Distribution of Pollutants in the Waters of an Aquatic Ecosystem in Northern Mexico
Ochoa-Rivero, Jesús Manuel; Reyes-Fierro, Ana Victoria; Peralta-Pérez, Ma. Del Rosario; Zavala-Díaz de la Serna, Francisco Javier; Ballinas-Casarrubias, Lourdes; Salmerón, Ivan; Rubio-Arias, Héctor; Rocha-Gutiérrez, Beatriz A.
2017-01-01
The availability of good quality water resources is essential to ensure healthy crops and livestock. The objective of this study was to evaluate the level of pollution in Bustillos Lagoon in northern Mexico. Physical-chemical parameters like sodium, chloride, sulfate, electrical conductivity, nitrates, and the pesticide dichlorodiphenyltrichloroethane (DDT) were analyzed to determine the water quality available in the lagoon. Although DDT has been banned in several countries, it is still used for agricultural purposes in Mexico and its presence in this area had not been analyzed previously. Bustillos Lagoon was divided into three zones for the evaluation: (1) industrial; (2) communal lands; and (3) agricultural. The highest concentrations of sodium (2360 mg/L) and SAR (41 meq/L) reported in the industrial zone are values exceeding the United Nations Food and Agricultural Organization (FAO) irrigation water quality guidelines. DDT and its metabolites were detected in all of the 21 sites analyzed, in the agricultural zone ∑DDTs = 2804 ng/mL, this level is much higher than those reported for other water bodies in Mexico and around the world where DDT has been used heavily. The water in the communal zone is the least contaminated, but can only be recommended for irrigation of plants with high stress tolerance and not for crops. PMID:28441345
Häring, Volker; Manka'abusi, Delphine; Akoto-Danso, Edmund K; Werner, Steffen; Atiah, Kofi; Steiner, Christoph; Lompo, Désiré J P; Adiku, Samuel; Buerkert, Andreas; Marschner, Bernd
2017-09-06
In large areas of sub-Saharan Africa crop production must cope with low soil fertility. To increase soil fertility, the application of biochar (charred biomass) has been suggested. In urban areas, untreated waste water is widely used for irrigation because it is a nutrient-rich year-round water source. Uncertainty exists regarding the interactions between soil properties, biochar, waste water and fertilization over time. The aims of this study were to determine these interactions in two typical sandy, soil organic carbon (SOC) and nutrient depleted soils under urban vegetable production in Tamale (Ghana) and Ouagadougou (Burkina Faso) over two years. The addition of biochar at 2 kg m -2 made from rice husks and corn cobs initially doubled SOC stocks but SOC losses of 35% occurred thereafter. Both biochar types had no effect on soil pH, phosphorous availability and effective cation exchange capacity (CEC) but rice husk biochar retained nitrogen (N). Irrigation with domestic waste water increased soil pH and exchangeable sodium over time. Inorganic fertilization alone acidified soils, increased available phosphorous and decreased base saturation. Organic fertilization increased SOC, N and CEC. The results from both locations demonstrate that the effects of biochar and waste water were less pronounced than reported elsewhere.
Levels and Distribution of Pollutants in the Waters of an Aquatic Ecosystem in Northern Mexico.
Ochoa-Rivero, Jesús Manuel; Reyes-Fierro, Ana Victoria; Peralta-Pérez, Ma Del Rosario; Zavala-Díaz de la Serna, Francisco Javier; Ballinas-Casarrubias, Lourdes; Salmerón, Ivan; Rubio-Arias, Héctor; Rocha-Gutiérrez, Beatriz A
2017-04-25
The availability of good quality water resources is essential to ensure healthy crops and livestock. The objective of this study was to evaluate the level of pollution in Bustillos Lagoon in northern Mexico. Physical-chemical parameters like sodium, chloride, sulfate, electrical conductivity, nitrates, and the pesticide dichlorodiphenyltrichloroethane (DDT) were analyzed to determine the water quality available in the lagoon. Although DDT has been banned in several countries, it is still used for agricultural purposes in Mexico and its presence in this area had not been analyzed previously. Bustillos Lagoon was divided into three zones for the evaluation: (1) industrial; (2) communal lands; and (3) agricultural. The highest concentrations of sodium (2360 mg/L) and SAR (41 meq/L) reported in the industrial zone are values exceeding the United Nations Food and Agricultural Organization (FAO) irrigation water quality guidelines. DDT and its metabolites were detected in all of the 21 sites analyzed, in the agricultural zone ∑DDTs = 2804 ng/mL, this level is much higher than those reported for other water bodies in Mexico and around the world where DDT has been used heavily. The water in the communal zone is the least contaminated, but can only be recommended for irrigation of plants with high stress tolerance and not for crops.
Ni, Li; Zheng, Weichao; Zhang, Qiang; Cao, Wei; Li, Baoming
2016-10-01
The effectiveness of slightly acidic electrolyzed water (SAEW) in reducing Escherichia coli, Salmonella typhimurim, Staphylococcus aureus or bacterial mixtures on stainless steel surfaces was evaluated and compared its efficacy with composite phenol solution for reducing total aerobic bacteria in animal transport vehicles. Stainless steel surfaces were inoculated with these strains individually or in a mixture, and sprayed with SAEW, composite phenol, or alkaline electrolyzed water for 0.5, 1, 1.5 and 2min. The bactericidal activity of SAEW increased with increasing available chlorine concentration and spraying duration. The SAEW solution of 50mgl -1 of available chlorine concentration showed significantly higher effectiveness than composite phenol in reducing the pathogens on stainless steel surfaces (P<0.05). Complete inactivation of pathogens on stainless steel surfaces were observed after treatment with alkaline electrolyzed water followed by SAEW at 50mgl -1 of available chlorine concentration for 2min or alkaline electrolyzed water treatment followed by SAEW treatment at 90mgl -1 of available chlorine concentration for 0.5min. The efficacy of SAEW in reducing total aerobic bacteria in animal transport vehicles was also determined. Vehicles in the disinfection booth were sprayed with the same SAEW, alkaline electrolyzed water and composite phenol solutions using the automatic disinfection system. Samples from vehicle surfaces were collected with sterile cotton swabs before and after each treatment. No significant differences in bactericidal efficiency were observed between SAEW and composite phenol for reducing total aerobic bacteria in the vehicles (P>0.05). SAEW was also found to be more effective when used in conjunction with alkaline electrolyzed water. Results suggest that the bactericidal efficiency of SAEW was higher than or equivalent to that of composite phenol and SAEW may be used as effective alternative for reducing microbial contamination of animal transport vehicles. Copyright © 2016 Elsevier B.V. All rights reserved.
First passage Brownian functional properties of snowmelt dynamics
NASA Astrophysics Data System (ADS)
Dubey, Ashutosh; Bandyopadhyay, Malay
2018-04-01
In this paper, we model snow-melt dynamics in terms of a Brownian motion (BM) with purely time dependent drift and difusion and examine its first passage properties by suggesting and examining several Brownian functionals which characterize the lifetime and reactivity of such stochastic processes. We introduce several probability distribution functions (PDFs) associated with such time dependent BMs. For instance, for a BM with initial starting point x0, we derive analytical expressions for : (i) the PDF P(tf|x0) of the first passage time tf which specify the lifetime of such stochastic process, (ii) the PDF P(A|x0) of the area A till the first passage time and it provides us numerous valuable information about the total fresh water availability during melting, (iii) the PDF P(M) associated with the maximum size M of the BM process before the first passage time, and (iv) the joint PDF P(M; tm) of the maximum size M and its occurrence time tm before the first passage time. These P(M) and P(M; tm) are useful in determining the time of maximum fresh water availability and in calculating the total maximum amount of available fresh water. These PDFs are examined for the power law time dependent drift and diffusion which matches quite well with the available data of snowmelt dynamics.
Soil-vegetation feedbacks driving early ecosystems genesis
NASA Astrophysics Data System (ADS)
Gwenzi, Willis; Hinz, Christoph; McGrath, Gavan; Veneklaas, Erik
2010-05-01
During the early phase of terrestrial ecosystems genesis feedbacks between soil and vegetation may become a key driver determining whether and how the systems will converge to a stable state. This is particular true for water-limited ecosystems for which water availability determines biomass. Based on a review of how vegetation growth affects soil hydraulic properties, we propose a simple conceptual model that captures the feedbacks between soil water storage in soil and soil hydraulic behaviour and vegetation biomass. The feedbacks that we considered are (i) vegetation biomass and soil water storage, (ii) root growth and infiltration capacity, (iii) vegetation biomass and bare soil evaporation, and (iv) root growth and soil water drainage. In water-limited environments, these feedbacks are responsible for highly organized vegetation patterns in space and may also lead to oscillating behaviour of soil water storage and vegetation biomass in time. Biomass overshooting as a result of initially high soil water content is predicted, which is consistent with observations made in forested catchments after clearing or during re-vegetation of mine tailings. We furthermore study how the oscillation of rainfall and evaporative demand affects the biomass fluctuations in time. We can show that such systems may converge to either an equilibrium point or a limit cycle. Climate oscillation can cause period doubling and for large periods it may control the biomass dynamics.
Valuation of irrigation water in South-western Iran using a hedonic pricing model
NASA Astrophysics Data System (ADS)
Esmaeili, Abdoulkarim; Shahsavari, Zahra
2011-12-01
Population growth, improved socioeconomic conditions, increased demand for various types of water use, and a reduction in water supply has created more competition for scarce water supplies leveling many countries. Efficient allocation of water supplies between different economic sectors is therefore very important. Water valuation is a useful tool to determine water price. Water pricing can play a major part in improving water allocation by encouraging users to conserve scarce water resources, and promoting improvements in productivity. We used a hedonic pricing method to reveal the implicit value of irrigation water by analyzing agricultural land values in farms under the Doroodzan dam in South-western Iran. The method was applied to farms in which irrigation water came from wells and canals. The availability of irrigation water was one of the most important factors influencing land prices. The value of irrigation water in the farms investigated was estimated to be 0.046 per cubic meter. The estimated price for water was clearly higher than the price farmers currently pay for water in the area of study. Efficient water pricing could help the sustainability of the water resources. Farmers must therefore be informed of the real value of irrigation water used on their land.
Accurate determination of brain metabolite concentrations using ERETIC as external reference.
Zoelch, Niklaus; Hock, Andreas; Heinzer-Schweizer, Susanne; Avdievitch, Nikolai; Henning, Anke
2017-08-01
Magnetic Resonance Spectroscopy (MRS) can provide in vivo metabolite concentrations in standard concentration units if a reliable reference signal is available. For 1 H MRS in the human brain, typically the signal from the tissue water is used as the (internal) reference signal. However, a concentration determination based on the tissue water signal most often requires a reliable estimate of the water concentration present in the investigated tissue. Especially in clinically interesting cases, this estimation might be difficult. To avoid assumptions about the water in the investigated tissue, the Electric REference To access In vivo Concentrations (ERETIC) method has been proposed. In this approach, the metabolite signal is compared with a reference signal acquired in a phantom and potential coil-loading differences are corrected using a synthetic reference signal. The aim of this study, conducted with a transceiver quadrature head coil, was to increase the accuracy of the ERETIC method by correcting the influence of spatial B 1 inhomogeneities and to simplify the quantification with ERETIC by incorporating an automatic phase correction for the ERETIC signal. Transmit field ( B1+) differences are minimized with a volume-selective power optimization, whereas reception sensitivity changes are corrected using contrast-minimized images of the brain and by adapting the voxel location in the phantom measurement closely to the position measured in vivo. By applying the proposed B 1 correction scheme, the mean metabolite concentrations determined with ERETIC in 21 healthy subjects at three different positions agree with concentrations derived with the tissue water signal as reference. In addition, brain water concentrations determined with ERETIC were in agreement with estimations derived using tissue segmentation and literature values for relative water densities. Based on the results, the ERETIC method presented here is a valid tool to derive in vivo metabolite concentration, with potential advantages compared with internal water referencing in diseased tissue. Copyright © 2017 John Wiley & Sons, Ltd.
Non-invasive assessment of leaf water status using a dual-mode microwave resonator.
Dadshani, Said; Kurakin, Andriy; Amanov, Shukhrat; Hein, Benedikt; Rongen, Heinz; Cranstone, Steve; Blievernicht, Ulrich; Menzel, Elmar; Léon, Jens; Klein, Norbert; Ballvora, Agim
2015-01-01
The water status in plant leaves is a good indicator for the water status in the whole plant revealing stress if the water supply is reduced. The analysis of dynamic aspects of water availability in plant tissues provides useful information for the understanding of the mechanistic basis of drought stress tolerance, which may lead to improved plant breeding and management practices. The determination of the water content in plant tissues during plant development has been a challenge and is currently feasible based on destructive analysis only. We present here the application of a non-invasive quantitative method to determine the volumetric water content of leaves and the ionic conductivity of the leaf juice from non-invasive microwave measurements at two different frequencies by one sensor device. A semi-open microwave cavity loaded with a ceramic dielectric resonator and a metallic lumped-element capacitor- and inductor structure was employed for non-invasive microwave measurements at 150 MHz and 2.4 Gigahertz on potato, maize, canola and wheat leaves. Three leaves detached from each plant were chosen, representing three developmental stages being representative for tissue of various age. Clear correlations between the leaf- induced resonance frequency shifts and changes of the inverse resonator quality factor at 2.4 GHz to the gravimetrically determined drying status of the leaves were found. Moreover, the ionic conductivity of Maize leaves, as determined from the ratio of the inverse quality factor and frequency shift at 150 MHz by use of cavity perturbation theory, was found to be in good agreement with direct measurements on plant juice. In conjunction with a compact battery- powered circuit board- microwave electronic module and a user-friendly software interface, this method enables rapid in-vivo water amount assessment of plants by a handheld device for potential use in the field.
Soil moisture and biogeochemical factors influence the distribution of annual Bromus species
Belnap, Jayne; Stark, John Thomas; Rau, Benjamin; Allen, Edith B.; Phillips, Sue
2016-01-01
Abiotic factors have a strong influence on where annual Bromus species are found. At the large regional scale, temperature and precipitation extremes determine the boundaries of Bromusoccurrence. At the more local scale, soil characteristics and climate influence distribution, cover, and performance. In hot, dry, summer-rainfall-dominated deserts (Sonoran, Chihuahuan), little or noBromus is found, likely due to timing or amount of soil moisture relative to Bromus phenology. In hot, winter-rainfall-dominated deserts (parts of the Mojave Desert), Bromus rubens is widespread and correlated with high phosphorus availability. It also responds positively to additions of nitrogen alone or with phosphorus. On the Colorado Plateau, with higher soil moisture availability, factors limiting Bromus tectorum populations vary with life stage: phosphorus and water limit germination, potassium and the potassium/magnesium ratio affect winter performance, and water and potassium/magnesium affect spring performance. Controlling nutrients also change with elevation. In cooler deserts with winter precipitation (Great Basin, Columbia Plateau) and thus even greater soil moisture availability, B. tectorum populations are controlled by nitrogen, phosphorus, or potassium. Experimental nitrogen additions stimulate Bromus performance. The reason for different nutrients limiting in dissimilar climatic regions is not known, but it is likely that site conditions such as soil texture (as it affects water and nutrient availability), organic matter, and/or chemistry interact in a manner that regulates nutrient availability and limitations. Under future drier, hotter conditions,Bromus distribution is likely to change due to changes in the interaction between moisture and nutrient availability.
NASA Astrophysics Data System (ADS)
Wright, Hannah R.; Dodd, Ian C.; Blackwell, Martin S. A.; Surridge, Ben W. J.
2015-04-01
Soil drying and rewetting (DRW) affects the forms and availability of phosphorus (P). Water soluble P has been reported to increase 1.8- to 19-fold after air-drying with the majority of the increase (56-100%) attributable to organic P. Similarly, in two contrasting soil types DRW increased concentrations of total P and reactive P in leachate, likely due to enhanced P mineralisation and physiochemical processes causing detachment of soil colloids, with faster rewetting rates related to higher concentrations of P. The intensity of drying as well as the rate of rewetting influences organic and inorganic P cycling. How these dynamics are driven by soil water status, and impact crop P acquisition and growth, remains unclear. Improving P and water use efficiencies and crop yields is globally important as both P and water resources become increasingly scarce, whilst demand for food increases. Irrigation supply below the water requirement for full crop evapotranspiration is employed by agricultural practitioners where water supply is limited. Regulated deficit irrigation describes the scheduling of water supply to correspond to the times of highest crop demand. Alternate wetting and drying (AWD) is applied in lowland irrigated rice production to avoid flooding at certain times of crop development, and has benefited P nutrition and yields. This research aims to optimise the benefits of P availability and uptake achieved by DRW by guiding deficit irrigation management strategies. Further determination of underlying processes driving P cycling at fluctuating soil moisture status is required. Presented here is a summary of the literature on DRW effects on soil P availability and plant P uptake and partitioning, in a range of soil types and cropping systems, with emphasis on alternate wetting and drying irrigation (AWD) compared to continuous flooding in lowland irrigated rice production. Soil water contents and matric potentials, and effects on P dynamics, are highly variable across studies (at laboratory, greenhouse and field scales). Aiming to understand this variation, two sets of results are presented. Firstly, the effects of soil type on responses to DRW, and relationships between soil gravimetric water content and matric potential and thresholds at which DRW increases P availability, are shown and physiological implications suggested (from laboratory experiments). Further evidence is given for the role of the microbial biomass in elevated P availability, and P increased in soil that was partially air-dried and maintained above -1.5 MPa, the permanent wilting point. Secondly, effects of DRW on soil P availability, plant P nutrition, water use and physiology in pot-grown plants are shown (from glasshouse experiments). Soil P availability has been quantified by water and sodium bicarbonate extracts, and plant P concentrations via ICP-OES. Further understanding the effects of soil water status on P cycling is needed to improve irrigation and other management strategies to optimise P and water use efficiencies and crop yields. Thus, future experiments will investigate how different sources of P (organic and inorganic) respond to DRW regimes (including field experiments).
Comparison of Hydrologic Data from Monroe County, Michigan, 1991-2001
Nicholas, J.R.; Blumer, Stephen P.; McGowan, Rose M.
2001-01-01
In the summer of 2001, there were renewed concerns about the effects of quarry dewatering on nearby domestic ground-water supplies in Monroe County, Michigan. Reports of domestic wells “going dry” are not uncommon historically in Monroe County. Such reports have been linked to droughts, nearby irrigation, quarrying, and other large ground-water uses since as early as 1900 (Sherzer, 1900). Concerns about ground-water availability during the short, but extreme, drought of 1988 prompted the County and the State of Michigan to cooperate with the USGS (U.S. Geological Survey) on a county water resources assessment during the early 1990s (Nicholas and others, 1996). Aquifers in Monroe County generally yield sufficient water for domestic supplies. High transmissivities and low storage in fractured carbonate aquifers and poor water quality at depth (Nicholas and others, 1996), however, make domestic supplies very susceptible to the effects of drought and large withdrawals. Therefore, there are legitimate concerns about sustainable groundwater supplies in the County. Additionally, significant increases in ground-water uses in Monroe County during the past decade coincide with very dry years during the late 1990s. Although ground-water-level data were collected by Monroe County during the last decade, there are not comparable data sets available for many water uses. Therefore, determining whether concerns about domestic wells going dry can be linked to ground-water withdrawals or climate is problematic. In response to recent concerns, the USGS and MDEQ (Michigan Department of Environmental Quality) entered into a cooperative agreement in October 2001 to conduct a study regarding the availability of ground water in Monroe County. The major goal of this study is to determine how widespread are the impacts of quarry dewatering operations. This report summarizes the initial phase of the study which consists of a comparison of hydrologic data from 1991 to 2001. The 1991 data are reported by the USGS in the report by Nicholas and others (1996). Later data come from a variety of sources including USGS, MDEQ, Monroe County, National Oceanic and Atmospheric Administration, U.S. Army Corps of Engineers, and ground-water users. All non-USGS data in this report are given as reported; data verification was not a part of this initial phase. The types of data chosen for comparison in this report include water levels of Lake Erie, precipitation at Monroe, streamflow in the River Raisin at Manchester, ground-water use, ground-water levels, and ground-water quality. The authors acknowledge the cooperation and provision of data and information by several agencies. Ground-water use for irrigation was provided by Ron Van Til of MDEQ. Quarry discharges were provided by Jennifer Rogers of MDEQ. Ground-water-level data for 1993 to 2001 were provided by the Monroe County Health Department. The authors also acknowledge Carlos Hernandez, Chris Hoard, Tom Morgan, Tom Sabin, and Dave Westjohn for collecting streamflow, ground-water, and ground-water-quality data in autumn, 2001. Sharon Baltusis and Jaye Lunsford assisted in the compilation and presentation of hydrologic data in this report.
NASA Astrophysics Data System (ADS)
Monaco, Eugenia; Alfieri, Silvia Maria; Basile, Angelo; Menenti, Massimo; Bonfante, Antonello; De Lorenzi, Fracesca
2014-05-01
Climate evolution may lead to changes in the amount and distribution of precipitations and to reduced water availability, with constraints on the cultivation of some crops. Recently, foreseen crop responses to climate change raise a crucial question for the agricultural stakeholders: are the current production systems resilient to this change? An active debate is in progress about the definition of adaptation of agricultural systems, particularly about the integrated assessment of climate stressors, vulnerability and resilece towards the evaluation of climate impact on agricultural systems. Climate change represents a risk for rain-fed agricultural systems, where irrigations cannot compensate reductions in precipitations. The intra-specific biodiversity of crops can be a resource towards adaptation. The knowledge of the responses to environmental conditions (temperature and water availability) of different cultivars can allow to identify options for adaptation to future climate. Simulation models of water flow in the soil-plant-atmosphere system, driven by different climate scenarios, can describe present and foreseen soil water regime. The present work deals with a case-study on the adaptive capacity of durum wheat to climate change. The selected study area is a hilly region in Southern Italy (Fortore Beneventano, Campania Region). Two climate cases were studied: "reference" (1961-1990) and "future" (2021-2050). A mechanistic model of water flow in the soil-plant-atmosphere system (SWAP) was run to determine the water regime in some soil units, representative of the soil variability in the study area. From model output, the Relative Evapotranspiration Deficit (RETD) was determined as an indicator of hydrological conditions during the crop growing period for each year and climate case; and periods with higher frequencies of soil water deficits were identified. The timing of main crop development stages was calculated. The occurrence of water deficit at different development stages was thus assessed. Moreover, the yield response functions to water availability of several durum wheat cultivars were determined; cultivars' hydrologic requirements were thus defined and compared with the simulated values of RETD. The latter was evaluated against requirements for each soil unit, cultivar and year in both climate cases to assess adaptability. In the future climate scenario a significant reduction (about 80 mm) of rainfall is foreseen. The analyses of inter- and intra-annual courses of the indicator (RETD) showed higher RETD in one soil unit, which resulted less suitable for durum wheat cultivation. According to the soils' water regime and to the cultivar-specific yield responses, the adaptability of durum wheat cultivars was assessed. The difference between the two climate cases was significant; the adaptability of the cultivars was strongly influenced by the different rainfall regime and by the soil physical properties, which strongly affected the soil water balance. The case study showed how in the future climate case, for rainfed durum wheat, the intra-specific variability will allow to maintain the current crop production system. The work was carried out within the Italian national project AGROSCENARI funded by the Ministry for Agricultural, Food and Forest Policies (MIPAAF, D.M. 8608/7303/2008)
Li, Ronghui; Pan, Wei; Guo, Jinchuan; Pang, Yong; Wu, Jianqiang; Li, Yiping; Pan, Baozhu; Ji, Yong; Ding, Ling
2014-05-01
The basis for submerged plant restoration in surface water is to research the complicated dynamic mechanism of water transparency. In this paper, through the impact factor analysis of water transparency, the suspended sediment, dissolved organic matter, algae were determined as three main impactfactors for water transparency of Neijiang River in Eastern China. And the multiple regression equation of water transparency and sediment concentration, permanganate index, chlorophyll-a concentration was developed. Considering the complicated transport and transformation of suspended sediment, dissolved organic matter and algae, numerical model of them were developed respectively for simulating the dynamic process. Water transparency numerical model was finally developed by coupling the sediment, water quality, and algae model. These results showed that suspended sediment was a key factor influencing water transparency of Neijiang River, the influence of water quality indicated by chemical oxygen demand and algal concentration indicated by chlorophyll a were indeterminate when their concentrations were lower, the influence was more obvious when high concentrations are available, such three factors showed direct influence on water transparency.
FLUORIDE CONTENT OF COMMERCIALLY AVAILABLE BOTTLED DRINKING WATER IN BANGKOK, THAILAND.
Rirattanapong, Praphasri; Rirattanapong, Opas
2016-09-01
The use of bottled drinking water may be a source of fluoride and could be a risk factor for fluorosis among infants and young children. The aim of this study was to evaluate the fluoride content of commercially available bottled drinking water in Bangkok, Thailand. Forty-five water samples (15 samples of plain water and 30 samples of mineral water) were purchased from several supermarkets in Bangkok, Thailand. Three bottles of each water sample were purchased, and the fluoride content of each sample was measured twice using a combination fluoride-ion selective electrode. The average reading for each sample was then calculated. Data were analyzed by descriptive statistics. Differences between mineral and plain water samples were determined by Student’s t-test. The mean (±SD) fluoride content for all the water samples was 0.17 (±0.17) mg F/l (range: 0.01-0.89 mg F/l). Six brands (13%) tested stated the fluoride content on the label. The actual fluoride content in each of their brands varied little from the label. Eight samples (18%) had a fluoride content >0.3 mg F/l and two samples (4%) had a fluoride content >0.6 mg F/l. The mean mineral water fluoride concentration was significantly higher than the mean fluoride concentration of plain water (p=0.001). We found commercially sold bottled drinking water in Bangkok, Thailand contained varying concentrations of fluoride; some with high concentrations of fluoride. Health professions need to be aware this varying fluoride content of bottled drinking water and educate the parents of infants and small children about this when prescribing fluoride supplements. Consideration should be made to have fluoride content put on the label of bottled water especially among brands with a content >0.3 mg F/l.
WETAIR: A computer code for calculating thermodynamic and transport properties of air-water mixtures
NASA Technical Reports Server (NTRS)
Fessler, T. E.
1979-01-01
A computer program subroutine, WETAIR, was developed to calculate the thermodynamic and transport properties of air water mixtures. It determines the thermodynamic state from assigned values of temperature and density, pressure and density, temperature and pressure, pressure and entropy, or pressure and enthalpy. The WETAIR calculates the properties of dry air and water (steam) by interpolating to obtain values from property tables. Then it uses simple mixing laws to calculate the properties of air water mixtures. Properties of mixtures with water contents below 40 percent (by mass) can be calculated at temperatures from 273.2 to 1497 K and pressures to 450 MN/sq m. Dry air properties can be calculated at temperatures as low as 150 K. Water properties can be calculated at temperatures to 1747 K and pressures to 100 MN/sq m. The WETAIR is available in both SFTRAN and FORTRAN.
Simple treatment of cotton textile to impart high water repellent properties
NASA Astrophysics Data System (ADS)
Ivanova, N. A.; Zaretskaya, A. K.
2010-12-01
We describe two methods to impart the water repellency for the surface of cotton fabric, using a commercially available and a laboratory synthesized fluoroalkylsiloxanes. To characterize the wettability and the durability of water repellent properties of hydrophobic coating produced, we have studied the advancing water contact angles, rolling angles and the evolution of water contact angle in time during a continuous contact of the surface with the water drop. The quality of the coatings was also assessed after the washing procedure. The analysis of the wettability of hydrophobized fabrics indicated that a better effect, leading to the superhydrophobic state of the surface, was observed when the surface relief of the fabric with the coating is determined by not only the structure and braiding of the fabric, but also the additional elements of texture created by the aggregates of molecules of hydrophobic agent.
Rapid depressurization event analysis in BWR/6 using RELAP5 and contain
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mueftueoglu, A.K.; Feltus, M.A.
1995-09-01
Noncondensable gases may become dissolved in Boiling Water Reactor (BWR) water level instrumentation during normal operations. Any dissolved noncondensable gases inside these water columns may come out of solution during rapid depressurization events, and displace water from the reference leg piping resulting in a false high level. These water level errors may cause a delay or failure in actuation, or premature shutdown of the Emergency Core Cooling System. (ECCS). If a rapid depressurization causes an erroneously high water level, preventing automatic ECCS actuation, it becomes important to determine if there would be other adequate indications for operator response and othermore » signals for automatic actuation such as high drywell pressure. It is also important to determine the effect of the level signal on ECCS operation after it is being actuated. The objective of this study is to determine the detailed coupled containment/NSSS response during this rapid depressurization events in BWR/6. The selected scenarios involve: (a) inadvertent opening of all ADS valves, (b) design basis (DB) large break loss of coolant accident (LOCA), and (c) main steam line break (MSLB). The transient behaviors are evaluated in terms of: (a) vessel pressure and collapsed water level response, (b) specific transient boundary conditions, (e.g., scram, MSIV closure timing, feedwater flow, and break blowdown rates), (c) ECCS initiation timing, (d) impact of operator actions, (e) whether indications besides low-low water level were available. The results of the analysis had shown that there would be signals to actuate ECCS other than low reactor level, such as high drywell pressure, low vessel pressure, high suppression pool temperature, and that the plant operators would have significant indications to actuate ECCS.« less
Liang, Yuzhen; Kuo, Dave T F; Allen, Herbert E; Di Toro, Dominic M
2016-10-01
There is concern about the environmental fate and effects of munition constituents (MCs). Polyparameter linear free energy relationships (pp-LFERs) that employ Abraham solute parameters can aid in evaluating the risk of MCs to the environment. However, poor predictions using pp-LFERs and ABSOLV estimated Abraham solute parameters are found for some key physico-chemical properties. In this work, the Abraham solute parameters are determined using experimental partition coefficients in various solvent-water systems. The compounds investigated include hexahydro-1,3,5-trinitro-1,3,5-triazacyclohexane (RDX), octahydro-1,3,5,7-tetranitro-1,3,5,7-tetraazacyclooctane (HMX), hexahydro-1-nitroso-3,5-dinitro-1,3,5-triazine (MNX), hexahydro-1,3,5-trinitroso-1,3,5-triazine (TNX), hexahydro-1,3-dinitroso-5- nitro-1,3,5-triazine (DNX), 2,4,6-trinitrotoluene (TNT), 1,3,5-trinitrobenzene (TNB), and 4-nitroanisole. The solvents in the solvent-water systems are hexane, dichloromethane, trichloromethane, octanol, and toluene. The only available reported solvent-water partition coefficients are for octanol-water for some of the investigated compounds and they are in good agreement with the experimental measurements from this study. Solvent-water partition coefficients fitted using experimentally derived solute parameters from this study have significantly smaller root mean square errors (RMSE = 0.38) than predictions using ABSOLV estimated solute parameters (RMSE = 3.56) for the investigated compounds. Additionally, the predictions for various physico-chemical properties using the experimentally derived solute parameters agree with available literature reported values with prediction errors within 0.79 log units except for water solubility of RDX and HMX with errors of 1.48 and 2.16 log units respectively. However, predictions using ABSOLV estimated solute parameters have larger prediction errors of up to 7.68 log units. This large discrepancy is probably due to the missing R2NNO2 and R2NNO2 functional groups in the ABSOLV fragment database. Copyright © 2016. Published by Elsevier Ltd.
Ong, Kheng Yong; Lim, Wei Ching; Ooi, Shing Ming; Loh, Zhi Hui; Kong, Ming Chai; Chan, Lai Wah; Heng, Paul Wan Sia
2017-05-01
There are no commercially available nasal irrigation solutions containing corticosteroids. Instead, such preparations are extemporaneously prepared by adding existing corticosteroid formulations to nasal irrigation solutions. The stability of the corticosteroid betamethasone 17-valerate (B17V), in nasal irrigation solutions of different compositions and pH and stored under different temperatures, was studied to determine the optimal choice of solution and storage conditions. Triplicate extemporaneous preparations made with B17V were prepared by adding a predetermined volume of B17V lotion to each nasal irrigation solution: normal saline (NS), sodium bicarbonate (NaHCO 3 ) powder dissolved in tap water, and a commercially available powder mixture (FLO Sinus Care Powder), dissolved in tap water or pre-boiled tap water. Preparations were stored at 30°C and 4°C. Sampling was carried out at 0, 1, 2, 6, and 24 hours. The concentrations of B17V and its degradation compound, betamethasone 21-valerate (B21V), were determined by high-performance liquid chromatography. Preparations stored at 30°C contained a lower amount of B17V and higher amount of B21V than those stored at 4°C. B17V stability in nasal irrigation solutions decreased in the following order: NS, FLO in fresh tap water, FLO in pre-boiled tap water, and NaHCO 3 . The degradation rate of B17V increased with higher storage temperature and higher pH. B17V is most stable when added to NS and least stable in NaHCO 3 solution. FLO solution prepared with either cooled boiled water or tap water is an alternative if administered immediately. Storage at 4°C can better preserve stability of B17V, over a period of 24 hours. © 2017 ARS-AAOA, LLC.
Pagliero, Liliana; Bouraoui, Fayçal; Willems, Patrick; Diels, Jan
2014-01-01
The Water Framework Directive of the European Union requires member states to achieve good ecological status of all water bodies. A harmonized pan-European assessment of water resources availability and quality, as affected by various management options, is necessary for a successful implementation of European environmental legislation. In this context, we developed a methodology to predict surface water flow at the pan-European scale using available datasets. Among the hydrological models available, the Soil Water Assessment Tool was selected because its characteristics make it suitable for large-scale applications with limited data requirements. This paper presents the results for the Danube pilot basin. The Danube Basin is one of the largest European watersheds, covering approximately 803,000 km and portions of 14 countries. The modeling data used included land use and management information, a detailed soil parameters map, and high-resolution climate data. The Danube Basin was divided into 4663 subwatersheds of an average size of 179 km. A modeling protocol is proposed to cope with the problems of hydrological regionalization from gauged to ungauged watersheds and overparameterization and identifiability, which are usually present during calibration. The protocol involves a cluster analysis for the determination of hydrological regions and multiobjective calibration using a combination of manual and automated calibration. The proposed protocol was successfully implemented, with the modeled discharges capturing well the overall hydrological behavior of the basin. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.
NASA Astrophysics Data System (ADS)
Li, Danfeng; Gao, Guangyao; Shao, Ming'an; Fu, Bojie
2016-07-01
A detailed understanding of soil hydraulic properties, particularly the available water content of soil, (AW, cm3 cm-3), is required for optimal water management. Direct measurement of soil hydraulic properties is impractical for large scale application, but routinely available soil particle-size distribution (PSD) and bulk density can be used as proxies to develop various prediction functions. In this study, we compared the performance of the Arya and Paris (AP) model, Mohammadi and Vanclooster (MV) model, Arya and Heitman (AH) model, and Rosetta program in predicting the soil water characteristic curve (SWCC) at 34 points with experimental SWCC data in an oasis-desert transect (20 × 5 km) in the middle reaches of the Heihe River basin, northwestern China. The idea of the three models emerges from the similarity of the shapes of the PSD and SWCC. The AP model, MV model, and Rosetta program performed better in predicting the SWCC than the AH model. The AW determined from the SWCCs predicted by the MV model agreed better with the experimental values than those derived from the AP model and Rosetta program. The fine-textured soils were characterized by higher AW values, while the sandy soils had lower AW values. The MV model has the advantages of having robust physical basis, being independent of database-related parameters, and involving subclasses of texture data. These features make it promising in predicting soil water retention at regional scales, serving for the application of hydrological models and the optimization of soil water management.
Climate change impacts on food system
NASA Astrophysics Data System (ADS)
Zhang, X.; Cai, X.; Zhu, T.
2014-12-01
Food system includes biophysical factors (climate, land and water), human environments (production technologies and food consumption, distribution and marketing), as well as the dynamic interactions within them. Climate change affects agriculture and food systems in various ways. Agricultural production can be influenced directly by climatic factors such as mean temperature rising, change in rainfall patterns, and more frequent extreme events. Eventually, climate change could cause shift of arable land, alteration of water availability, abnormal fluctuation of food prices, and increase of people at risk of malnutrition. This work aims to evaluate how climate change would affect agricultural production biophysically and how these effects would propagate to social factors at the global level. In order to model the complex interactions between the natural and social components, a Global Optimization model of Agricultural Land and Water resources (GOALW) is applied to the analysis. GOALW includes various demands of human society (food, feed, other), explicit production module, and irrigation water availability constraint. The objective of GOALW is to maximize global social welfare (consumers' surplus and producers' surplus).Crop-wise irrigation water use in different regions around the world are determined by the model; marginal value of water (MVW) can be obtained from the model, which implies how much additional welfare benefit could be gained with one unit increase in local water availability. Using GOALW, we will analyze two questions in this presentation: 1) how climate change will alter irrigation requirements and how the social system would buffer that by price/demand adjustment; 2) how will the MVW be affected by climate change and what are the controlling factors. These results facilitate meaningful insights for investment and adaptation strategies in sustaining world's food security under climate change.
Mas-Pla, Josep; Menció, Anna
2018-04-11
Climate change will affect the dynamics of the hydrogeological systems and their water resources quality; in particular nitrate, which is herein taken as a paradigmatic pollutant to illustrate the effects of climate change on groundwater quality. Based on climatic predictions of temperature and precipitation for the horizon of 2021 and 2050, as well as on land use distribution, water balances are recalculated for the hydrological basins of distinct aquifer systems in a western Mediterranean region as Catalonia (NE Spain) in order to determine the reduction of available water resources. Besides the fact that climate change will represent a decrease of water availability, we qualitatively discuss the modifications that will result from the future climatic scenarios and their impact on nitrate pollution according to the geological setting of the selected aquifers. Climate effects in groundwater quality are described according to hydrological, environmental, socio-economic, and political concerns. Water reduction stands as a major issue that will control stream-aquifer interactions and subsurface recharge, leading to a general modification of nitrate in groundwater as dilution varies. A nitrate mass balance model provides a gross estimation of potential nitrate evolution in these aquifers, and it points out that the control of the fertilizer load will be crucial to achieve adequate nitrate content in groundwater. Reclaimed wastewater stands as local reliable resource, yet its amount will only satisfy a fraction of the loss of available resources due to climate change. Finally, an integrated management perspective is necessary to avoid unplanned actions from private initiatives that will jeopardize the achievement of sustainable water resources exploitation under distinct hydrological scenarios.
NASA Astrophysics Data System (ADS)
Muller, M. F.; Gorelick, S.; Muller-Itten, M. C.
2015-12-01
The allocation of transboundary freshwater resources is a ubiquitous challenge with direct repercussions on the political stability of the concerned region. Under the right conditions, the need to share scarce water resources can act as a catalyst for dialogue between otherwise hostile neighbors. Yet the strategic reluctance of the involved parties to share water diversion and use data remains a major barrier that raises the probability of conflict. In that context, high-quality satellite data are progressively available to monitor water resources beyond political boundaries. These datasets have an increasing role to play in the allocation of shared waters. We develop a game theoretical framework to predict their effect on transboundary water negotiations. We consider repetitions of a game between two countries that have a water allocation agreement for transboundary river flow. The upstream country can observe the available flow in any given year and decide whether or not to provide her neighbor with the agreed upon river discharge. The downstream country cannot observe the initially available flow. He only observes the water allocated provided by his upstream neighbor and can take actions to impose a sanction on her if he can confidently determine that the agreement has been breached. In that context, satellite monitoring data will affect the informational advantage of the upstream country and increase her probability of either abiding by the agreement or being caught when breaching it. We find that the informed equilibrium will produce a lower probability of conflict, but changes in both players' positions regarding equitable allocation may destabilize the existing agreement in the short term.
Hydrologic reconnaissance of western Arctic Alaska, 1976 and 1977
Childers, Joseph M.; Kernodle, Donald R.; Loeffler, Robert M.
1979-01-01
Reconnaissance water-resource investigations were conducted on the western Alaskan Arctic Slope during April 1976 and August 1977; these months are times of winter and summer low flow. The information gathered is important for coordinated development in the area. Such development has been spurred by oil and gas discoveries on the North Slope, most notably at Prudhoe Bay. Little water resources information is currently available. The study area extended from the Colville River to the vicinity of Kotzebue. It included the western Arctic Slope and the western foothills of the Brooks Range. Nine springs, nine lakes and eleven rivers were sampled during the April 1976 reconnaissance trip. Its purpose was to locate winter flow and describe its quantity and quality. Field water-quality measurements made at these sites were: ice thickness, water depth, discharge (spring and streams), specific conductance, water temperature, dissolved oxygen, alkalinity (bicarbonate, HOC3), and pH. A followup summer trip was made in August 1977 to determine flood characteristics of twenty selected streams. Bankfull and maximum evident flood-peak discharges were determined by measuring channel geometry and estimating channel roughness. Aquatic invertebrate samples were collected at springs and flood survey sites visited during both reconnaissance trips. (Woodard-USGS)
Statistical analysis of short-term water stress conditions at Riggs Creek OzFlux tower site
NASA Astrophysics Data System (ADS)
Azmi, Mohammad; Rüdiger, Christoph; Walker, Jeffrey P.
2017-10-01
A large range of indices and proxies are available to describe the water stress conditions of an area subject to different applications, which have varying capabilities and limitations depending on the prevailing local climatic conditions and land cover. The present study uses a range of spatio-temporally high-resolution (daily and within daily) data sources to evaluate a number of drought indices (DIs) for the Riggs Creek OzFlux tower site in southeastern Australia. Therefore, the main aim of this study is to evaluate the statistical characteristics of individual DIs subject to short-term water stress conditions. In order to derive a more general and therefore representative DI, a new criterion is required to specify the statistical similarity between each pair of indices to allow determining the dominant drought types along with their representative DIs. The results show that the monitoring of water stress at this case study area can be achieved by evaluating the individual behaviour of three clusters of (i) vegetation conditions, (ii) water availability and (iii) water consumptions. This indicates that it is not necessary to assess all individual DIs one by one to derive a comprehensive and informative data set about the water stress of an area; instead, this can be achieved by analysing one of the DIs from each cluster or deriving a new combinatory index for each cluster, based on established combination methods.
Diesel-fired self-pumping water heater
NASA Astrophysics Data System (ADS)
Gertsmann, Joseph
1994-07-01
The object of this project was to study the feasibility of pumping and heating water by sustained oscillatory vaporization and condensation in a fired heat exchanger. Portable field liquid fueled water heaters would facilitate heating water for sanitation, personal hygiene, food service, laundry, equipment maintenance, and decontamination presently available only from larger, less portable, motorized pumping units. The technical tasks consisted of: development of an analytical model, operation of proof-of-principal prototypes, and determination of the thermal and mechanical relationships to evaluate operating range and control characteristics. Four successive pump models were analyzed and tested. The final analytical model gave reasonable agreement with the experimental results, indicating that the actual pumping effect was an order of magnitude lower than originally anticipated. It was concluded that a thermally-activated self pumping water heater based on the proposed principle is not feasible.
NASA Technical Reports Server (NTRS)
Oren, R.; Vane, G.; Zimmermann, R.; Carrere, V.; Realmuto, V.; Zebker, Howard A.; Schoeneberger, P.; Schoeneberger, M.
1991-01-01
The Tropical Rainforest Ecology Experiment (TREE) had two primary objectives: (1) to design a method for mapping vegetation in tropical regions using remote sensing and determine whether the result improves on available vegetation maps; and (2) to test a specific hypothesis on plant/water relations. Both objectives were thought achievable with the combined information from the Thermal Infrared Multispectral Scanner (TIMS), Airborne Visible/Infrared Imaging Spectrometer (AVIRIS), and Airborne Synthetic Aperture Radar (AIRSAR). Implicitly, two additional objectives were: (1) to ascertain that the range within each variable potentially measurable with the three instruments is large enough in the site, relative to the sensitivity of the instruments, so that differences between ecological groups may be detectable; and (2) to determine the ability of the three systems to quantify different variables and sensitivities. We found that the ranges in values of foliar nitrogen concentration, water availability, stand structure and species composition, and plant/water relations were large, even within the upland broadleaf vegetation type. The range was larger when other vegetation types were considered. Unfortunately, cloud cover and navigation errors compromised the utility of the TIMS and AVIRIS data. Nevertheless, the AIRSAR data alone appear to have improved on the available vegetation map for the study area. An example from an area converted to a farm is given to demonstrate how the combined information from AIRSAR, TIMS, and AVIRIS can uniquely identify distinct classes of land use. The example alludes to the potential utility of the three instruments for identifying vegetation at an ecological scale finer than vegetation types.
Bratkowska, D; Fontanals, N; Cormack, P A G; Borrull, F; Marcé, R M
2012-02-17
A monolithic, hydrophilic stir bar coating based upon a copolymer of methacrylic acid and divinylbenzene [poly(MAA-co-DVB)] was synthesised and evaluated as a new polymeric phase for the stir bar sorptive extraction (SBSE) of polar compounds from complex environmental water samples. The experimental conditions for the extraction and liquid desorption in SBSE were optimised. Liquid chromatography-triple quadrupole mass spectrometry (LC-MS/MS) was used for the determination of a group of polar pharmaceuticals in environmental water matrices. The extraction performance of the poly(MAA-co-DVB) stir bar was compared to the extraction performance of a commercially available polydimethylsiloxane stir bar; it was found that the former gave rise to significantly higher extraction efficiency of polar analytes (% recovery values near to 100% for most of the studied analytes) than the commercial product. The developed method was applied to determine the studied analytes at low ng L⁻¹ in different complex environmental water samples. Copyright © 2011 Elsevier B.V. All rights reserved.
The U.S. EPA’s in vitro bioaccessibility (IVBA) method 9200.1-86 defines a validated analytical procedure for the determination of lead bioaccessibility in contaminated soils. The method requires the use of a custom-fabricated extraction device that uses a heated water bath for ...
The supply of nitrogen substrates available for bacterial production in seawater was determined using the activities of ammonia assimilation enzymes, glutamine synthetase (GS) and glutamate dehydrogenase (GDH). Expression of GS and GDH by bacteria in pure culture is generally ind...
Public-Facilities Locator For The Blind
NASA Technical Reports Server (NTRS)
Moore, Kevin D.
1988-01-01
Proposed optoelectronic system guides blind people to important locations in public buildings, With system, sightless person easily determines directions and distances of restrooms, water fountains, stairways, emergency exits, and elevators. Circuitry uncomplicated and inexpensive, in both transmitter and receiver. Readily-available light-emitting diodes, photodiodes, and integrated-circuit chips used to build locator aid for the blind.
75 FR 54497 - Ocean Dumping; Guam Ocean Dredged Material Disposal Site Designation
Federal Register 2010, 2011, 2012, 2013, 2014
2010-09-08
... of special scientific importance, and other legitimate uses of the ocean. Minor short-term... option available since 1997. EPA determined that there is a long-term need for an ocean disposal site... Guam and surrounding waters. This is based on the long-term need to support the Naval and commercial...
33 CFR 211.74 - Public notice of the availability of land for sale.
Code of Federal Regulations, 2010 CFR
2010-07-01
... conditions, reservations and restrictions as the Chief of Engineers or the Director of Civil Works (Assistant to the Chief of Engineers for Civil Works) may determine to be necessary for the management and... of land for sale. 211.74 Section 211.74 Navigation and Navigable Waters CORPS OF ENGINEERS...
NASA Astrophysics Data System (ADS)
Qin, Jing-Yu; Geng, Yi-Zhao; Lü, Gang; Ji, Qing; Fang, Hai-Ping
2018-02-01
Not Available Project supported by the National Natural Science Foundation of China (Grant No. 11605038) and the Open Project Program of State Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, Chinese Academy of Sciences, China (Grant No. Y5KF211CJ1).
Federal Register 2010, 2011, 2012, 2013, 2014
2010-10-06
... single facility in one city (ASSRT, 2007). There are currently no fish consumption advisories in effect... substantial deleterious effects on aquatic life. Effects from these elements and compounds on fish include... quality as a result of eutrophication. In a simulation of the effects of water temperature on available...
Developing design methods of concrete mix with microsilica additives for road construction
NASA Astrophysics Data System (ADS)
Dmitrienko, Vladimir; Shrivel, Igor; Kokunko, Irina; Pashkova, Olga
2017-10-01
Based on the laboratory test results, regression equations having standard cone and concrete strength, to determine the available amount of cement, water and microsilica were obtained. The joint solution of these equations allowed the researchers to develop the algorithm of designing heavy concrete compositions with microsilica additives for road construction.
Responses of redwood soil microbial community structure and N transformations to climate change
Damon C. Bradbury; Mary K. Firestone
2012-01-01
Soil microorganisms perform critical ecosystem functions, including decomposition, nitrogen (N) mineralization and nitrification. Soil temperature and water availability can be critical determinants of the rates of these processes as well as microbial community composition and structure. This research examined how changes in climate affect bacterial and fungal...
Sponsor Referee: Douglas F. Barofsky, Oregon State University Concentration factors of 1000 and more reveal dozens of compounds in extracts of water supplies. Library mass spectra for most of these compounds are not available, and alternative means of identification are needed. D...
Ground-water quality protection; why it's important to you
Webbers, Ank
1995-01-01
Ground water is a valuable resource often used for industry, commerce, agriculture, and drinking water. In the 19080's, ground water provided 35 percent of the municipal water supplies in the United States and 95 percent of the rural, domestic drinking water. Scientists participating in ground-water studies may determine the potential pathways that contaminants could be transported in aquifers. In karst terrain especially, a contanimant can enter a fracture network in a carbonate aquifer and quickly spread to become a widespread health problem. Although Federal and local funding for ground-water cleanups and treatment may be available, the costs can exceed many millions of dollars each year. Such costly remedial actions could be avoided or minimized by becoming aware that ground water anywhere is vulnerable to contamination, but particularly so in carbonate terrain. Practicing good "out-of-doors" house- keeping is necessary. From the standpoint of economic and environmental responsibility, it is critical that we all work together to protect the quality of ground-water resources so that future generations can continue to have clean water.
Reliance on deep soil water in the tree species Argania spinosa.
Zunzunegui, M; Boutaleb, S; Díaz Barradas, M C; Esquivias, M P; Valera, J; Jáuregui, J; Tagma, T; Ain-Lhout, F
2017-12-07
In South-western Morocco, water scarcity and high temperature are the main factors determining species survival. Argania spinosa (L.) Skeels is a tree species, endemic to Morocco, which is suffering from ongoing habitat shrinkage. Argan trees play essential local ecological and economic roles: protecting soils from erosion, shading different types of crops, helping maintain soil fertility and, even more importantly, its seeds are used by the local population for oil production, with valuable nutritional, medicinal and cosmetic purposes. The main objective of this study was to identify the sources of water used by this species and to assess the effect of water availability on the photosynthetic rate and stem water potential in two populations: one growing on the coast and a second one 10 km inland. Stem water potential, photosynthetic rate and xylem water isotopic composition (δ18O) were seasonally monitored during 2 years. Trees from both populations showed a similar strategy in the use of the available water sources, which was strongly dependent on deep soil water throughout the year. Nevertheless, during the wet season or under low precipitation a more complex water uptake pattern was found with a mixture of water sources, including precipitation and soil at different depths. No evidence was found of the use of either groundwater or atmospheric water in this species. Despite the similar water-use strategy, the results indicate that Argania trees from the inland population explored deeper layers than coastal ones as suggested by more depleted δ18O values recorded in the inland trees and better photosynthetic performance, hence suggesting that the coastal population of A. spinosa could be subjected to higher stress. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Katner, Adrienne; Lackovic, Michelle; Streva, Kate; Paul, Vanessa; Trachtman, William Clay
2015-01-01
The objective of this assessment was to identify and evaluate data sets for use in the surveillance of arsenic hazards and private well drinking water use in Louisiana. Features, strengths, and limitations of the data sets are described, and prioritization criteria are applied to identify areas in need of further monitoring or outreach. Recent efforts have been made by the Environmental Public Health Tracking Network to evaluate the quality of private well water data for the purpose of supporting state and national surveillance activities. Like most states, Louisiana does not collect or mandate reporting of private well water quality data. Therefore, responding to public concerns about private well water quality requires an identification and evaluation of existing data. Data evaluated include measures of arsenic in groundwater and soil, private well water use, and biomonitoring results. The Environmental Protection Agency's Safe Drinking Water Information System and the US Geological Survey's Water Use data set were the most informative, nationally available data sets for conducting private well water arsenic surveillance. Three priority parishes were identified on the basis of a selection criteria, although all parishes require more private well sampling data. While the data reviewed enabled preliminary identification of parishes in need of monitoring and outreach, data limitations (particularly, a lack of statewide well water quality data) prevent a comprehensive evaluation of well water arsenic hazards and private well water use. A large number of unregistered wells further impede risk determination. Reliance on existing data sources is necessary, but development of metadata documentation is essential to prevent data misinterpretation. Increased outreach and policies to promote or mandate private well testing and reporting are needed to enable a comprehensive private well water tracking system.
Assessment of the performance of water harvesting systems in semi-arid regions
NASA Astrophysics Data System (ADS)
Lasage, Ralph
2016-04-01
Water harvesting is widely practiced and has the potential to improve water availability for domestic and agricultural use in semi-arid regions. New funds are becoming available to stimulate the implementation of water harvesting projects, for meeting the Sustainable Development Goals and to help communities to adapt to climate change. For this, it is important to understand which factors determine the success of water harvesting techniques under different conditions. For this, we review the literature, including information on the crop yield impacts of water harvesting projects in semi-arid Africa and Asia. Results show that large water harvesting structures (> 500 m3) are less expensive than small structures, when taking into account investment costs, storage capacity and lifetimes. We also find that water harvesting improves crop yields significantly, and that the relative impact of water harvesting on crop yields is largest in low rainfall years. We also see that the governance, technical knowledge and initial investment are more demanding for the larger structures than for smaller structures, which may affect their spontaneous adoption and long term sustainability when managed by local communities. To support the selection of appropriate techniques, we present a decision framework based on case specific characteristics. This framework can also be used when reporting and evaluating the performance of water harvesting techniques, which is up to now quite limited in peer reviewed literature. Based on Bouma, J., Hegde, S.E., Lasage, R., (2016). Assessing the returns to water harvesting: A meta-analysis. Agricultural Water Management 163, 100-109. Lasage, R., Verburg P.H., (2015). Evaluation of small scale water harvesting techniques for semi-arid environments. Journal of Arid Environments 118, 48-57.
NASA Astrophysics Data System (ADS)
Mehrdad Mirsanjari, Mir; Mohammadyari, Fatemeh
2018-03-01
Underground water is regarded as considerable water source which is mainly available in arid and semi arid with deficient surface water source. Forecasting of hydrological variables are suitable tools in water resources management. On the other hand, time series concepts is considered efficient means in forecasting process of water management. In this study the data including qualitative parameters (electrical conductivity and sodium adsorption ratio) of 17 underground water wells in Mehran Plain has been used to model the trend of parameters change over time. Using determined model, the qualitative parameters of groundwater is predicted for the next seven years. Data from 2003 to 2016 has been collected and were fitted by AR, MA, ARMA, ARIMA and SARIMA models. Afterward, the best model is determined using information criterion or Akaike (AIC) and correlation coefficient. After modeling parameters, the map of agricultural land use in 2016 and 2023 were generated and the changes between these years were studied. Based on the results, the average of predicted SAR (Sodium Adsorption Rate) in all wells in the year 2023 will increase compared to 2016. EC (Electrical Conductivity) average in the ninth and fifteenth holes and decreases in other wells will be increased. The results indicate that the quality of groundwater for Agriculture Plain Mehran will decline in seven years.
Rubio, K S; Ajemian, M; Stunz, G W; Palmer, T A; Lebreton, B; Beseres Pollack, J
2018-06-22
The Baffin Bay estuary is a hypersaline system in the Gulf of Mexico that supports an important recreational and commercial fishery for black drum Pogonias cromis, a benthic predator. Seasonal measurements of water quality variables, benthic macrofauna densities and biomass, and determination of P. cromis food sources using stomach-content and stable-isotope analyses were carried out to determine how P. cromis food sources change with water quality and how this may affect P. cromis diet. Gut-content analysis indicated P. cromis selectively consumed bivalves Mulinia lateralis and Anomalocardia auberiana. Isotope compositions demonstrated that P. cromis relied on these benthic food resources produced in the Baffin Bay estuary year-round. Biomass and densities of these bivalves were influenced by changes in water quality variables, particularly salinity and dissolved oxygen. Thus, this paper demonstrates the relationship between water quality variables, benthic macrofauna, and their use as food resources by a carnivorous fish species, and emphasizes the need for integrated assessments when studying the effects of water quality on ecosystem function. Holistic approaches such as these can provide important information for management and conservation of fishery resources and can improve predictions of ecosystem response to climate variability. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
NASA Astrophysics Data System (ADS)
Kretzschmar, T.; Hernandez, R.; Valenzuela, C.; Cabello, A.
2012-12-01
In the Baja California peninsula are several watersheds present, of which the hydrogeological conditions are of great importance to communities in the area. The Valle de Guadalupe watershed, for instance has a wine industry of national importance. Irrigation of crops is carried out exclusively with water from the aquifer, which consists of Quaternary sediments filling this depression of Post-Miocene age. Apart from the use of the aquifer by the wine industry, the water utility of Ensenada operates 10 drinking water wells with a total capacity of 320 L/s or 42% of supply in the valley. In the arid northern Mexico mountain front recharge is an important recharge source to the aquifers. Other important recharge sources are related to direct infiltration of the precipitation, recharge from runoff into streams (mountain block recharge) and the provision by active faults. The knowledge of the aquifer is crucial to maintain sustainable management of water resources in the Valle de Guadalupe. This intense use of water resources is reflected in a degradation of the aquifer water quality and reduced water table. The integrated approach for a sustainable evaluation and usage of the aquifer includes besides the hydrogeological evaluation, the determination of the water stress on the vineyards as well as the usage of treated waste water as alternative resource as well the evaluation of the effects of climatic variations and measurement and modeling of the vegetation, the main interface between atmosphere and soil, affecting the hydrology in the process of interception, infiltration, runoff and evapotranspiration. With these detailed ongoing studies we expect to identify and counter imbalance of water in the study area. This requires 1) modeling and hydrogeological studies for the determination of the present and future imbalance 2) estimation of the impacts of industrial activities on water resources 3) characterization of alternative water sources, 4) optimization of the water use and 5) water reuse to counter the hydrologic imbalance. The cultivation of the vine is largely governed by the water availability from precipitation. Water stress caused by annual rainfall lower than 350 mm produces a decrease in photosynthetic activity. This stress reduces growth and affects the balance between sugar concentration, organic acids and pH leading to a reduced productivity. The average annual rainfall for Ensenada, Baja California is 285 mm which requires additional water supply for the vines. Although the water has become a scarce resource and the growing conflicts in water availability in Baja California, there are very few studies assessing the water needs of this plant in the region. The groundwater extraction in the study area result in a significant hydrologic imbalance with a deficit of up to 20 Mm3y-1 with significant fluctuation in groundwater recharge estimates ranging from 5 Mm3y-1 to up to over 50 Mmy-1 depending on the annual precipitation. Detailed studies including the establishment of a recharge field laboratory are going on to precise these values and to be able to counter the present imbalance of water to reach sustainable water availability in the basins in coming decades.
Colman, John A.; Massey, Andrew J.; Brandt, Sara L.
2011-09-16
Dilution of aluminum discharged to reservoirs in filter-backwash effluents at water-treatment facilities in Massachusetts was investigated by a field study and computer simulation. Determination of dilution is needed so that permits for discharge ensure compliance with water-quality standards for aquatic life. The U.S. Environmental Protection Agency chronic standard for aluminum, 87 micrograms per liter (μg/L), rather than the acute standard, 750 μg/L, was used in this investigation because the time scales of chronic exposure (days) more nearly match rates of change in reservoir concentrations than do the time scales of acute exposure (hours).Whereas dilution factors are routinely computed for effluents discharged to streams solely on the basis of flow of the effluent and flow of the receiving stream, dilution determination for effluents discharged to reservoirs is more complex because (1), compared to streams, additional water is available for dilution in reservoirs during low flows as a result of reservoir flushing and storage during higher flows, and (2) aluminum removal in reservoirs occurs by aluminum sedimentation during the residence time of water in the reservoir. Possible resuspension of settled aluminum was not considered in this investigation. An additional concern for setting discharge standards is the substantial concentration of aluminum that can be naturally present in ambient surface waters, usually in association with dissolved organic carbon (DOC), which can bind aluminum and keep it in solution.A method for dilution determination was developed using a mass-balance equation for aluminum and considering sources of aluminum from groundwater, surface water, and filter-backwash effluents and losses caused by sedimentation, water withdrawal, and spill discharge from the reservoir. The method was applied to 13 reservoirs. Data on aluminum and DOC concentrations in reservoirs and influent water were collected during the fall of 2009. Complete reservoir volume was determined to be available for mixing on the basis of vertical and horizontal aluminum-concentration profiling. Losses caused by settling of aluminum were assumed to be proportional to aluminum concentration and reservoir area. The constant of proportionality, as a function of DOC concentration, was established by simulations in each of five reservoirs that differed in DOC concentration.In addition to computing dilution factors, the project determined dilution factors that would be protective with the same statistical basis (frequency of exceedance of the chronic standard) as dilutions computed for streams at the 7-day-average 10-year-recurrence annual low flow (the 7Q10). Low-flow dilutions are used for permitting so that receiving waters are protected even at the worst-case flow levels. The low-flow dilution factors that give the same statistical protection are the lowest annual 7-day-average dilution factors with a recurrence of 10 years, termed 7DF10s. Determination of 7DF10 values for reservoirs required that long periods of record be simulated so that dilution statistics could be determined. Dilution statistics were simulated for 13 reservoirs from 1960 to 2004 using U.S. Geological Survey Firm-Yield Estimator software to model reservoir inputs and outputs and present-day values of filter-effluent discharge and aluminum concentration.Computed settling velocities ranged from 0 centimeters per day (cm/d) at DOC concentrations of 15.5 milligrams per liter (mg/L) to 21.5 cm/d at DOC concentrations of 2.7 mg/L. The 7DF10 values were a function of aluminum effluent discharged. At current (2009) effluent discharge rates, the 7DF10 values varied from 1.8 to 115 among the 13 reservoirs. In most cases, the present-day (2009) discharge resulted in receiving water concentrations that did not exceed the standard at the 7DF10. Exceptions were one reservoir with a very small area and three reservoirs with high concentrations of DOC. Maximum permissible discharges were determined for water-treatment plants by adjusting discharges upward in simulations until the 7DF10 resulted in reservoir concentrations that just met the standard. In terms of aluminum flux, these discharges ranged from 0 to 28 kilograms of aluminum per day.
Coupled Crop/Hydrology Model to Estimate Expanded Irrigation Impact on Water Resources
NASA Astrophysics Data System (ADS)
Handyside, C. T.; Cruise, J.
2017-12-01
A coupled agricultural and hydrologic systems model is used to examine the environmental impact of irrigation in the Southeast. A gridded crop model for the Southeast is used to determine regional irrigation demand. This irrigation demand is used in a regional hydrologic model to determine the hydrologic impact of irrigation. For the Southeast to maintain/expand irrigated agricultural production and provide adaptation to climate change and climate variability it will require integrated agricultural and hydrologic system models that can calculate irrigation demand and the impact of the this demand on the river hydrology. These integrated models can be used as (1) historical tools to examine vulnerability of expanded irrigation to past climate extremes (2) future tools to examine the sustainability of expanded irrigation under future climate scenarios and (3) a real-time tool to allow dynamic water resource management. Such tools are necessary to assure stakeholders and the public that irrigation can be carried out in a sustainable manner. The system tools to be discussed include a gridded version of the crop modeling system (DSSAT). The gridded model is referred to as GriDSSAT. The irrigation demand from GriDSSAT is coupled to a regional hydrologic model developed by the Eastern Forest Environmental Threat Assessment Center of the USDA Forest Service) (WaSSI). The crop model provides the dynamic irrigation demand which is a function of the weather. The hydrologic model includes all other competing uses of water. Examples of use the crop model coupled with the hydrologic model include historical analyses which show the change in hydrology as additional acres of irrigated land are added to water sheds. The first order change in hydrology is computed in terms of changes in the Water Availability Stress Index (WASSI) which is the ratio of water demand (irrigation, public water supply, industrial use, etc.) and water availability from the hydrologic model. Also, statistics such as the number of times certain WASSI thresholds are exceeded are calculated to show the impact of expanded irrigation during times of hydrologic drought and the coincident use of water by other sectors. Also, integrated downstream impacts of irrigation are also calculated through changes in flows through the whole river systems.
Effects of groundwater abstraction on two keystone tree species in an arid savanna national park.
Shadwell, Eleanor; February, Edmund
2017-01-01
In arid systems with no surface water, deep boreholes in ephemeral river beds provide for humans and animals. With continually increasing infrastructure development for tourism in arid wildlife parks such as the Kgalagadi Transfrontier Park in southern Africa, we ask what effects increased abstraction may have on large trees. Large trees in arid savannas perform essential ecosystem services by providing food, shade, nesting sites and increased nutrients for many other plant and animal species and for this are regarded as keystone species. We determine seasonal fluctuations in the water table while also determining the water source for the dominant large tree species in the Auob and Nossob rivers in the Park. We also determine the extent to which these trees are physiologically stressed using leaf δ 13 C, xylem pressure potentials, specific leaf area and an estimate of canopy death. We do this both upstream and downstream of a low water use borehole in the Auob River and a high water use borehole in the Nossob River. Our results show that the trees are indeed using deep groundwater in the wet season and that this is the same water used by people. In the dry season, trees in the Auob downstream of the active borehole become detached from the aquifer and use more isotopically enriched soil water. In the Nossob in the dry season, all trees use isotopically enriched soil water, and downstream of the active borehole use stomatal regulation to maintain leaf water potentials. These results suggest that trees in the more heavily utilised Nossob are under more water stress than those trees in the Auob but that trees in both rivers demonstrate physiological adaptation to the changes in available water with smaller heavier leaves, no significant canopy dieback and in the dry season in the Nossob stomatal regulation of leaf water potentials. An increase in abstraction of groundwater particularly at the Nossob borehole may cause an additional draw down of the water table adding to the physiological stress demonstrated in our study. The managers of the Kgalagadi Transfrontier Park have a mandate that includes biodiversity conservation. To fulfil this mandate, upper and lower thresholds for groundwater abstraction that allow for an adequate ecological reserve have to be determined.
Effects of groundwater abstraction on two keystone tree species in an arid savanna national park
2017-01-01
Background In arid systems with no surface water, deep boreholes in ephemeral river beds provide for humans and animals. With continually increasing infrastructure development for tourism in arid wildlife parks such as the Kgalagadi Transfrontier Park in southern Africa, we ask what effects increased abstraction may have on large trees. Large trees in arid savannas perform essential ecosystem services by providing food, shade, nesting sites and increased nutrients for many other plant and animal species and for this are regarded as keystone species. Methods We determine seasonal fluctuations in the water table while also determining the water source for the dominant large tree species in the Auob and Nossob rivers in the Park. We also determine the extent to which these trees are physiologically stressed using leaf δ13C, xylem pressure potentials, specific leaf area and an estimate of canopy death. We do this both upstream and downstream of a low water use borehole in the Auob River and a high water use borehole in the Nossob River. Results Our results show that the trees are indeed using deep groundwater in the wet season and that this is the same water used by people. In the dry season, trees in the Auob downstream of the active borehole become detached from the aquifer and use more isotopically enriched soil water. In the Nossob in the dry season, all trees use isotopically enriched soil water, and downstream of the active borehole use stomatal regulation to maintain leaf water potentials. These results suggest that trees in the more heavily utilised Nossob are under more water stress than those trees in the Auob but that trees in both rivers demonstrate physiological adaptation to the changes in available water with smaller heavier leaves, no significant canopy dieback and in the dry season in the Nossob stomatal regulation of leaf water potentials. Discussion An increase in abstraction of groundwater particularly at the Nossob borehole may cause an additional draw down of the water table adding to the physiological stress demonstrated in our study. The managers of the Kgalagadi Transfrontier Park have a mandate that includes biodiversity conservation. To fulfil this mandate, upper and lower thresholds for groundwater abstraction that allow for an adequate ecological reserve have to be determined. PMID:28149693
Modelling the role of groundwater hydro-refugia in East African hominin evolution and dispersal
Cuthbert, M. O.; Gleeson, T.; Reynolds, S. C.; Bennett, M. R.; Newton, A. C.; McCormack, C. J.; Ashley, G. M.
2017-01-01
Water is a fundamental resource, yet its spatiotemporal availability in East Africa is poorly understood. This is the area where most hominin first occurrences are located, and consequently the potential role of water in hominin evolution and dispersal remains unresolved. Here, we show that hundreds of springs currently distributed across East Africa could function as persistent groundwater hydro-refugia through orbital-scale climate cycles. Groundwater buffers climate variability according to spatially variable groundwater response times determined by geology and topography. Using an agent-based model, grounded on the present day landscape, we show that groundwater availability would have been critical to supporting isolated networks of hydro-refugia during dry periods when potable surface water was scarce. This may have facilitated unexpected variations in isolation and dispersal of hominin populations in the past. Our results therefore provide a new environmental framework in which to understand how patterns of taxonomic diversity in hominins may have developed. PMID:28556825
Modelling the role of groundwater hydro-refugia in East African hominin evolution and dispersal
NASA Astrophysics Data System (ADS)
Cuthbert, M. O.; Gleeson, T.; Reynolds, S. C.; Bennett, M. R.; Newton, A. C.; McCormack, C. J.; Ashley, G. M.
2017-05-01
Water is a fundamental resource, yet its spatiotemporal availability in East Africa is poorly understood. This is the area where most hominin first occurrences are located, and consequently the potential role of water in hominin evolution and dispersal remains unresolved. Here, we show that hundreds of springs currently distributed across East Africa could function as persistent groundwater hydro-refugia through orbital-scale climate cycles. Groundwater buffers climate variability according to spatially variable groundwater response times determined by geology and topography. Using an agent-based model, grounded on the present day landscape, we show that groundwater availability would have been critical to supporting isolated networks of hydro-refugia during dry periods when potable surface water was scarce. This may have facilitated unexpected variations in isolation and dispersal of hominin populations in the past. Our results therefore provide a new environmental framework in which to understand how patterns of taxonomic diversity in hominins may have developed.
Determination of mean droplet sizes of water-in-oil emulsions using an Earth's field NMR instrument.
Fridjonsson, Einar O; Flux, Louise S; Johns, Michael L
2012-08-01
The use of the Earth's magnetic field (EF) to conduct nuclear magnetic resonance (NMR) experiments has a long history with a growing list of applications (e.g. ground water detection, diffusion measurements of Antarctic sea ice). In this paper we explore whether EFNMR can be used to accurately and practically measure the mean droplet size () of water-in-oil emulsions (paraffin and crude oil). We use both pulsed field gradient (PFG) measurements of restricted self-diffusion and T₂ relaxometry, as appropriate. T₂ relaxometry allows the extension of droplet sizing ability below the limits set by the available magnetic field gradient strength of the EFNMR apparatus. A commercially available bench-top NMR spectrometer is used to verify the results obtained using the EFNMR instrument, with good agreement within experimental error, seen between the two instruments. These results open the potential for further investigation of the application of EFNMR for emulsion droplet sizing. Copyright © 2012 Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Nachtnebel, Hans-Peter; Wesemann, Johannes; Herrnegger, Mathew; Senoner, Tobias; Schulz, Karsten
2015-04-01
Climate and Land Use Change can have severe impacts on natural water resources needed for domestic, agricultural and industrial water use. In order to develop adaptation strategies, it is necessary to assess the present and future vulnerability of the water resources on the basis of water quantity, water quality and adaptive capacity indicators. Therefore a methodological framework was developed within the CC-Ware project and a detailed assessment was performed for Austria. The Water Exploitation Index (WEI) is introduced as a quantitative indicator. It is defined as the ratio between the water demand and the water availability. Water availability is assessed by a high resolution grid-based water balance model, utilizing the meteorological information from bias corrected regional climate models. The demand term can be divided into domestic, agricultural and industrial water demand and is assessed on the water supply association level. The Integrated Groundwater Pollution Load Index (GWPLI) represents an indicator for areas at risk regarding water quality, considering agricultural loads (nitrate pollution loads), potential erosion and potential risks from landfills. Except for the landfills, the information for the current situation is based on the CORINE Landcover data. Future changes were predicted utilizing the PRELUDE land use scenarios. Since vulnerability is also dependent on the adaptive capacity of a system, the Adaptive Capacity Index is introduced. The Adaptive Capacity Index thereby combines the Ecosystem Service Index (ESSI), which represents three water related ecosystem services (Water Provision, Water Quantity Regulation and Water Quality Regulation) and the regional economic capacity expressed by the gross value added. On the basis of these indices, the Overall Vulnerability of the water resources can be determined for the present and the future. For Austria the different indices were elaborated. Maps indicating areas of different levels of vulnerability were developed. A comparison with existing data (River Basin Management Plan and Groundwater Chemistry Regulation) shows a good agreement between the elaborated maps and observations for the present state. The Overall Vulnerability is very low and low for most parts of Austria, especially in the forested alpine region. Bigger cities like Vienna, Graz and Linz show medium vulnerabilities, due to the high water demand and low ecosystem services. Only in the north-eastern and south-eastern part of the country some water supply associations with high and very high overall vulnerability exist. Groundwater recharge is quite small in these regions and the water quality is limited due to intense agriculture and possible threats through landfills. The developed framework allows an evaluation of water quantity and quality vulnerabilities for large scales for the present and the future. Including ecosystem services and gross value added an overall vulnerability can be determined.
Wangsness, David J.
1997-01-01
In the 1980s it was determined that existing ambient and compliance-monitoring data could not satisfactorily evaluate the results of hundreds of billions of dollars spent for water-pollution abatement in the United States. At the request of the US Congress, a new programme, the National Water-Quality Assessment, was designed and implemented by government agency, the US Geological Survey (USGS). The Assessment has reported status and trends in surface- and ground-water quality at national, regional, and local scales since 1991. The legislative basis for US monitoring and data-sharing policies are identified as well as the successive phases of the design and implementation of the USGS Assessment. Application to the Danube Basin is suggested. Much of the water-quality monitoring conducted in the United States is designed to comply with Federal and State laws mandated primarily by the Clean Water Act of 1987 and the Safe Drinking Water Act of 1986. Monitoring programs generally focus on rivers upstream and downstream of point-source discharges and at water-supply intakes. Few data are available for aquifer systems, and chemical analyses are often limited to those constituents required by law. In most cases, the majority of the available chemical and streamflow data have provided the information necessary to meet the objectives of the compliance-monitoring programs, but do not necessarily provide the information requires for basin-wide assessments of the water quality at the local, regional, or national scale.
Field Techniques for Estimating Water Fluxes Between Surface Water and Ground Water
Rosenberry, Donald O.; LaBaugh, James W.
2008-01-01
This report focuses on measuring the flow of water across the interface between surface water and ground water, rather than the hydrogeological or geochemical processes that occur at or near this interface. The methods, however, that use hydrogeological and geochemical evidence to quantify water fluxes are described herein. This material is presented as a guide for those who have to examine the interaction of surface water and ground water. The intent here is that both the overview of the many available methods and the in-depth presentation of specific methods will enable the reader to choose those study approaches that will best meet the requirements of the environments and processes they are investigating, as well as to recognize the merits of using more than one approach. This report is designed to make the reader aware of the breadth of approaches available for the study of the exchange between surface and ground water. To accomplish this, the report is divided into four chapters. Chapter 1 describes many well-documented approaches for defining the flow between surface and ground waters. Subsequent chapters provide an in-depth presentation of particular methods. Chapter 2 focuses on three of the most commonly used methods to either calculate or directly measure flow of water between surface-water bodies and the ground-water domain: (1) measurement of water levels in well networks in combination with measurement of water level in nearby surface water to determine water-level gradients and flow; (2) use of portable piezometers (wells) or hydraulic potentiomanometers to measure hydraulic gradients; and (3) use of seepage meters to measure flow directly. Chapter 3 focuses on describing the techniques involved in conducting water-tracer tests using fluorescent dyes, a method commonly used in the hydrogeologic investigation and characterization of karst aquifers, and in the study of water fluxes in karst terranes. Chapter 4 focuses on heat as a tracer in hydrological investigations of the near-surface environment.
The Effect of Moisture on the Hydrolysis of Basic Salts.
Shi, Xiaoyang; Xiao, Hang; Chen, Xi; Lackner, Klaus S
2016-12-19
A great deal of information exists concerning the hydration of ions in bulk water. Much less noticeable, but equally ubiquitous is the hydration of ions holding on to several water molecules in nanoscopic pores or in natural air at low relative humidity. Such hydration of ions with a high ratio of ions to water molecules (up to 1:1) are essential in determining the energetics of many physical and chemical systems. Herein, we present a quantitative analysis of the energetics of ion hydration in nanopores based on molecular modeling of a series of basic salts associated with different numbers of water molecules. The results show that the degree of hydrolysis of basic salts in the presence of a few water molecules is significantly different from that in bulk water. The reduced availability of water molecules promotes the hydrolysis of divalent and trivalent basic ions (S 2 - , CO 3 2- , SO 3 2- , HPO 4 2- , SO 4 2- , PO 4 3- ), which produces lower valent ions (HS - , HCO 3 - , HSO 3 - , H 2 PO 4 - , HSO 4 - , HPO 4 2- ) and OH - ions. However, reducing the availability of water inhibits the hydrolysis of monovalent basic ions (CN - , HS - ). This finding sheds some light on a vast number of chemical processes in the atmosphere and on solid porous surfaces. The discovery has wide potential applications including designing efficient absorbents for acidic gases. © 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
Zibordi, Giuseppe
2016-03-21
Determination of the water-leaving radiance LW through above-water radiometry requires knowledge of accurate reflectance factors ρ of the sea surface. Publicly available ρ relevant to above-water radiometry include theoretical data sets generated: i. by assuming a sky radiance distribution accounting for aerosols and multiple scattering, but neglecting polarization, and quantifying sea surface effects through Cox-Munk wave slope statistics; or differently ii. accounting for polarization, but assuming an ideal Rayleigh sky radiance distribution, and quantifying sea surface effects through modeled wave elevation and slope variance spectra. The impact on above-water data products of differences between those factors ρ was quantified through comparison of LW from the Ocean Color component of the Aerosol Robotic Network (AERONET-OC) with collocated LW from in-water radiometry. Results from the analysis of radiance measurements from the sea performed with 40 degrees viewing angle and 90 degrees azimuth offset with respect to the sun plane, indicated a slightly better agreement between above- and in-water LW determined for wind speeds tentatively lower than 4 m s-1 with ρ computed accounting for aerosols, multiple scattering and Cox-Munk surfaces. Nevertheless, analyses performed by partitioning the investigated data set also indicated that actual ρ values would exhibit dependence on sun zenith comprised between those characterizing the two sets of reflectance factors.
2010-08-01
available). It is assumed after this method is formally published that various standard vendors will offer other sources than the current single standard... single isomer. D Alkyl PAHs used to determine the SPME-GC/MS relative response factors including alkyl naphthalenes (1-methyl-, 2-methyl-, 1,2...Flag all compound results in the sample which were estimated above the upper calibration level with an “E” qualifier. 15. Precision and Bias 15.1 Single
NASA Astrophysics Data System (ADS)
Pivato, M.; Carniello, L.; Silvestri, S.; Marani, M.; Gardner, J.
2016-12-01
Water temperature represents one of the crucial factors driving the ecological processes in water bodies. Many contributions are available in the literature that describe temperature dynamics in deep basins as lakes or seas. Those basins are typically stratified which makes important to represent the vertical profile of the water temperature. Dealing with shallow water bodies, such as rivers, shallow lakes and lagoons, simplifies the problem because the water temperature can be assumed uniform in the water column. Conversely, the heat exchange at the soil-water interface assumes an important role in the water temperature dynamics. Notwithstanding, very few studies and data about this process are available in the literature. In order to provide more insight on the soil contribution to water temperature dynamics, we performed ad hoc field measurements in the Venice lagoon,. We selected a location on a tidal flat in the northern part of the lagoon, close to the Sant'Erasmo Island, where we measured the temperature within the water column and the first 1.5 m of the soil. Data collection started in July 2015 and is still ongoing. We used the data to characterize the heat flux at the water-soil interface in different periods of the year and to develop a "point" model for describing the evolution of the temperature in the water column. The insight on the process provided by the data and by the point model: i) enabled us to determine the soil thermal properties (diffusivity and heat capacity); ii) confirms the uniform profile of the water temperature in the water column; iii) demonstrates that the heat flux at the soil-water interface is comparable with other fluxes at the air-water interface and iv) highlights the important role exerted by advective water fluxes. The latter will be accounted for developing a module for describing the dynamic of the temperature to be coupled with an already existing 2D hydrodynamic model of the Venice lagoon.
Busenberg, Eurybiades; Plummer, Niel; Bartholomay, Roy C.; Wayland, Julian E.
1998-01-01
From July 1994 through May 1997, the U.S. Geological Survey in cooperation with the Department of Energy, sampled 86 wells completed in the Snake River Plain aquifer at and near the Idaho N ationa1 Engineering and Environmental Laboratory (INEEL). The wells were sampled for a variety of constituents including one- and two-carbon halocarbons. Concentrations of dichlorodifluoromethane (CFC-12), trichlorofluoromethane (CFC-11) and trichlorotrifluororoethane (CFC-113) were determined. The samples for halocarbon analysis were collected in 62-milliliter flame sealed borosilicate glass ampoules in the field. The data will be used to evaluate the ages of ground waters at INEEL. The ages of the ground water will be used to determine recharge rates, residence time, and travel time of water in the Snake River Plain aquifer in and near INEEL. The chromatograms of 139 ground waters are presented showing a large number of halomethanes, haloethanes, and haloethenes present in the ground waters underlying the INEEL. The chromatograms can be used to qualitatively evaluate a large number of contaminants at parts per trillion to parts per billion concentrations. The data can be used to study temporal and spatial distribution of contaminants in the Snake River Plain aquifer. Representative compressed chromatograms for all ground waters sampled in this study are available on two 3.5-inch high density computer disks. The data and the program required to decompress the data can be obtained from the U.S. Geological Survey office at Idaho Falls, Idaho. Sulfur hexafluoride (SF6) concentrations were measured in selected wells to determine the feasibility of using this environmental tracer as an age dating tool of ground water. Concentrations of dissolved nitrogen, argon, carbon dioxide, oxygen, and methane were measured in 79 ground waters. Concentrations of dissolved permanent gases are tabulated and will be used to evaluate the temperature of recharge of ground water in and near the INEEL.
Friedrich, Max N. D.; Binkert, Marc E.; Mosler, Hans-Joachim
2017-01-01
Handwashing has been shown to considerably reduce diarrhea morbidity and mortality. To decontaminate hands effectively, the use of running water, soap, and various scrubbing steps are recommended. This study aims to identify the behavioral determinants of effective handwashing. Everyday handwashing technique of 434 primary caregivers in high-density suburbs of Harare, Zimbabwe, was observed and measured as an 8-point sum score of effective handwashing technique. Multiple linear and logistic regression analyses were performed to predict observed handwashing technique from potential contextual and psychosocial determinants. Knowledge of how to wash hands effectively, availability of a handwashing station with functioning water tap, self-reported frequency of handwashing, perceived vulnerability, and action planning were the main determinants of effective handwashing technique. The models were able to explain 39% and 36% of the variance in overall handwashing technique and thoroughness of handscrubbing. Memory aids and guided practice are proposed to consolidate action knowledge, and personalized risk messages should increase the perceived vulnerability of contracting diarrhea. Planning where, when, and how to maintain a designated place for handwashing with sufficient soap and water is proposed to increase action planning. Since frequent self-reported handwashing was associated with performing more effective handwashing technique, behavior change interventions should target both handwashing frequency and technique concurrently. PMID:28044046
NASA Astrophysics Data System (ADS)
Zhuang, Yafeng; Zhou, Meng; Gu, Jia; Li, Xiangmei
2014-03-01
A new spectrophotometric method for the determination of trace amounts of bisphenol A based on a diazotization-coupling reaction was developed. In acidic solution, clenbuterol was first diazotized with sodium nitrite, then coupled with bisphenol A to from an azo-compound [I] in NH3-NH4Cl buffer, which shows a maximum absorption at 410 nm. The effects of the amount of sodium nitrite, diazo reaction time, the amount of clenbuterol, coupling reaction time and coupling reaction temperature have been examined. Under the optional conditions, the determination of the linear range of bisphenol A is 0.24-8.4 μg/mL, correlation coefficient is 0.9905 and detection limit of this method is 0.15 μg/mL. The spectrophotometric method is simple, rapid, high sensitivity with better accuracy. High performance liquid chromatography (HPLC) technique combined with this new spectrophotometric method has been also developed for the measurement of bisphenol A. The analysis was achieved on a C18 column using water and methanol as a mobile phase and the detection was done spectrophotometrically at 410 nm. These reported methods were applied to the determination of bisphenol A in hot water in contact with commercially available table-water bottle samples.
Azomethine H colorimetric method for determining dissolved boron in water
Spencer, R.R.; Erdmann, D.E.
1979-01-01
An automated colorimetric method for determining dissolved boron in water is described. The boron is complexed with azomethine H, which is readily available as the condensation product of H acid (8-amino-1-naphthol-3,6-disulfonic acid) and salicylaldehyde. The absorbance of the yellow complex formed is then measured colorimetrically at 410 nm. Interference effects from other dissolved species are minimized by the addition of diethylenetriaminepentaacetic acid (DTPA); however, iron, zinc, and bicarbonate interfere at concentrations above 400 ??g/L, 2000 ??g/L, and 200 mg/L, respectively. The bicarbonate interference can be eliminated by careful acidification of the sample with concentrated HCl to a pH between 5 and 6. Thirty samples per hour can be routinely analyzed over the range of from 10 to 400 ??g/L, boron.
Soil Temperature and Moisture Profile (STAMP) System Handbook
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cook, David R.
The soil temperature and moisture profile system (STAMP) provides vertical profiles of soil temperature, soil water content (soil-type specific and loam type), plant water availability, soil conductivity, and real dielectric permittivity as a function of depth below the ground surface at half-hourly intervals, and precipitation at one-minute intervals. The profiles are measured directly by in situ probes at all extended facilities of the SGP climate research site. The profiles are derived from measurements of soil energy conductivity. Atmospheric scientists use the data in climate models to determine boundary conditions and to estimate the surface energy flux. The data are alsomore » useful to hydrologists, soil scientists, and agricultural scientists for determining the state of the soil. The STAMP system replaced the SWATS system in early 2016.« less
Experimental datasets on engineering properties of expansive soil treated with common salt.
Durotoye, Taiwo O; Akinmusuru, Joseph O; Ogundipe, Kunle E
2018-06-01
Construction of highway pavements or high rise structures over the expansive soils are always problematic due to failures of volume change or swelling characteristic experienced in the water permeability of the soil. The data in this article represented summary of (Durotoye et al., 2016; Durotoye, 2016) [1], [2]. The data explored different percentages of sodium chloride as additive in stabilizing the engineering properties of expansive soil compared with other available stabilizer previously worked on. Experimental procedures carried out on expansive soil include: (Liquid limit, Plastic limit, Plasticity index, Shrinkage limit, Specific gravity Free swell index and Optimum water content) to determine the swelling parameters and (maximum dry density, California bearing ratio and unconfined compressive strength) to determine the strength parameters. The results of the experiment were presented in pie charts.
Climate change and farmers’ cropping patterns in Cemoro watershed area, Central Java, Indonesia
NASA Astrophysics Data System (ADS)
Sugihardjo; Sutrisno, J.; Setyono, P.; Suntoro
2018-03-01
Cropping pattern applied by farmers is usually based on the availability of water. Farmers cultivate rice when water is available. If it is unavailable, farmers will choose to plant crops that need less water. Climate change greatly affects to farmers in determining the cropping pattern as it alters the rainfall pattern and distribution in the region. This condition requires farmers to adjust the cropping pattern so that they can do the farming successfully. This study aims to examine the application of cropping patterns applied by the farmers in the Cemoro Watershed, Central Java, Indonesia. Descriptive analysis approach is employed in this research. The results showed that farmers’ cropping pattern is not based on the availability of water. However, it adopts a habit that has been practiced since long time ago or just adopt others farmer's habit. The cropping pattern applied by irrigated paddy farmers in Cemoro watershed area consists of two types: rice-rice-rice and rice-rice-secondary crops. Among those two types, most farmers apply the rice-rice-rice pattern. Meanwhile, there are three cropping patterns applied in the rain-land, namely rice-rice-rice, rice-rice-secondary crop, and rice-rice-fallow. The majority of farmers apply the second pattern (rice-rice-secondary crops). It was also found that farmers’ cropping pattern was not in accordance with the recommendation of the local government.
Hydrologic refugia, plants, and climate change.
McLaughlin, Blair C; Ackerly, David D; Klos, P Zion; Natali, Jennifer; Dawson, Todd E; Thompson, Sally E
2017-08-01
Climate, physical landscapes, and biota interact to generate heterogeneous hydrologic conditions in space and over time, which are reflected in spatial patterns of species distributions. As these species distributions respond to rapid climate change, microrefugia may support local species persistence in the face of deteriorating climatic suitability. Recent focus on temperature as a determinant of microrefugia insufficiently accounts for the importance of hydrologic processes and changing water availability with changing climate. Where water scarcity is a major limitation now or under future climates, hydrologic microrefugia are likely to prove essential for species persistence, particularly for sessile species and plants. Zones of high relative water availability - mesic microenvironments - are generated by a wide array of hydrologic processes, and may be loosely coupled to climatic processes and therefore buffered from climate change. Here, we review the mechanisms that generate mesic microenvironments and their likely robustness in the face of climate change. We argue that mesic microenvironments will act as species-specific refugia only if the nature and space/time variability in water availability are compatible with the ecological requirements of a target species. We illustrate this argument with case studies drawn from California oak woodland ecosystems. We posit that identification of hydrologic refugia could form a cornerstone of climate-cognizant conservation strategies, but that this would require improved understanding of climate change effects on key hydrologic processes, including frequently cryptic processes such as groundwater flow. © 2017 John Wiley & Sons Ltd.
Sladky, Kurt K.; Quist, Charlotte; Ramirez, Pedro; Hill, David; Dein, F. Joshua
2003-01-01
The effects of aquatic contaminants generated by soda ash mining processes on the North American eared grebe (Podiceps nigricollis) population illustrates important issues associated with human-induced habitat degradation on the health of migratory species. Eared grebes have been extensively studied in their staging and breeding habitats, but little is known about their 2- to 3-day migratory periods. During migration, few bodies of water are available to the birds for refuge between freshwater breeding areas in Canada and hypersaline lakes (e.g., Great Salt Lake in Utah or Mono Lake in California) to which they migrate. One geographic refuge area includes a series of "tailings" ponds associated with soda ash mining operations in southwestern Wyoming. The ponds range from 100-1200 acres, with water containing high concentrations of sodium decahydrate (Na2CO3•10H2O). At cool temperatures (generally < 40°F) sodium decahydrate precipitates out of the water and crystallizes on solid objects in the ponds or on the water surface. Bird mortality on these ponds has been recognized since the early 1970's, and the mining companies have developed hazing strategies and rehabilitation programs in order to minimize mortality. In order to determine causes of grebe mortality and devise strategies to reduce mortality, a field epidemiologic investigation was developed with the following objectives: 1) to determine whether eared grebes have quantifiable physiologic abnormalities associated with exposure to soda ash mine pond water; 2) to evaluate physical effects of sodium decahydrate crystallization on grebe survival; 3) to establish cause of death based on necropsy of deceased grebes; 4) to determine long-term survivability of eared grebes after exposure to the pond water; and 5) to evaluate water quality and determine whether aquatic invertebrates are present in the ponds as a possible food source.
Vegetative response to water availability on the San Carlos Apache Reservation
Petrakis, Roy; Wu, Zhuoting; McVay, Jason; Middleton, Barry R.; Dye, Dennis G.; Vogel, John M.
2016-01-01
On the San Carlos Apache Reservation in east-central Arizona, U.S.A., vegetation types such as ponderosa pine forests, pinyon-juniper woodlands, and grasslands have significant ecological, cultural, and economic value for the Tribe. This value extends beyond the tribal lands and across the Western United States. Vegetation across the Southwestern United States is susceptible to drought conditions and fluctuating water availability. Remotely sensed vegetation indices can be used to measure and monitor spatial and temporal vegetative response to fluctuating water availability conditions. We used the Moderate Resolution Imaging Spectroradiometer (MODIS)-derived Modified Soil Adjusted Vegetation Index II (MSAVI2) to measure the condition of three dominant vegetation types (ponderosa pine forest, woodland, and grassland) in response to two fluctuating environmental variables: precipitation and the Standardized Precipitation Evapotranspiration Index (SPEI). The study period covered 2002 through 2014 and focused on a region within the San Carlos Apache Reservation. We determined that grassland and woodland had a similar moderate to strong, year-round, positive relationship with precipitation as well as with summer SPEI. This suggests that these vegetation types respond negatively to drought conditions and are more susceptible to initial precipitation deficits. Ponderosa pine forest had a comparatively weaker relationship with monthly precipitation and summer SPEI, indicating that it is more buffered against short-term drought conditions. This research highlights the response of multiple, dominant vegetation types to seasonal and inter-annual water availability. This research demonstrates that multi-temporal remote sensing imagery can be an effective tool for the large scale detection of vegetation response to adverse impacts from climate change and support potential management practices such as increased monitoring and management of drought-affected areas. Different vegetation types displayed various responses to water availability, further highlighting the need for individual management plans for forest and woodland, especially considering the projected drier conditions in the Southwest U.S. and other arid or semi-arid regions around the world.
NASA Astrophysics Data System (ADS)
Okamoto, Kyosuke; Yi, Li; Asanuma, Hiroshi; Okabe, Takashi; Abe, Yasuyuki; Tsuzuki, Masatoshi
2018-02-01
A continuous water injection test was conducted to halt the reduction in steam production in the Okuaizu Geothermal Field, Japan. Understanding the factors triggering microseismicity associated with water injection is essential to ensuring effective steam production. We identified possible triggering processes by applying methods based on microseismic monitoring, including a new method to determine the presence of water in local fractures using scattered P-waves. We found that the evolving microseismicity near the injection point could be explained by a diffusion process and/or water migration. We also found that local microseismicity on a remote fault was likely activated by stress fluctuations resulting from changes in the injection rate. A mediator of this fluctuation might be water remaining in the fracture zone. After the injection was terminated, microseismicity possibly associated with the phase transition of the liquid was found. We conclude that a variety of triggering processes associated with water injection may exist.[Figure not available: see fulltext.
Seasonal Dynamics of Water Use Strategy of Two Salix Shrubs in Alpine Sandy Land, Tibetan Plateau.
Zhu, Yajuan; Wang, Guojie; Li, Renqiang
2016-01-01
Water is a limiting factor for plant growth and vegetation dynamics in alpine sandy land of the Tibetan Plateau, especially with the increasing frequency of extreme precipitation events and drought caused by climate change. Therefore, a relatively stable water source from either deeper soil profiles or ground water is necessary for plant growth. Understanding the water use strategy of dominant species in the alpine sandy land ecosystem is important for vegetative rehabilitation and ecological restoration. The stable isotope methodology of δD, δ18O, and δ13C was used to determine main water source and long-term water use efficiency of Salix psammophila and S. cheilophila, two dominant shrubs on interdune of alpine sandy land in northeastern Tibetan Plateau. The root systems of two Salix shrubs were investigated to determine their distribution pattern. The results showed that S. psammophila and S. cheilophila absorbed soil water at different soil depths or ground water in different seasons, depending on water availability and water use strategy. Salix psammophila used ground water during the growing season and relied on shallow soil water recharged by rain in summer. Salix cheilophila used ground water in spring and summer, but relied on shallow soil water recharged by rain in spring and deep soil water recharged by ground water in fall. The two shrubs had dimorphic root systems, which is coincident with their water use strategy. Higher biomass of fine roots in S. psammophila and longer fine roots in S. cheilophila facilitated to absorb water in deeper soil layers. The long-term water use efficiency of two Salix shrubs increased during the dry season in spring. The long-term water use efficiency was higher in S. psammophila than in S. cheilophila, as the former species is better adapted to semiarid climate of alpine sandy land.
Seasonal Dynamics of Water Use Strategy of Two Salix Shrubs in Alpine Sandy Land, Tibetan Plateau
Zhu, Yajuan; Wang, Guojie; Li, Renqiang
2016-01-01
Water is a limiting factor for plant growth and vegetation dynamics in alpine sandy land of the Tibetan Plateau, especially with the increasing frequency of extreme precipitation events and drought caused by climate change. Therefore, a relatively stable water source from either deeper soil profiles or ground water is necessary for plant growth. Understanding the water use strategy of dominant species in the alpine sandy land ecosystem is important for vegetative rehabilitation and ecological restoration. The stable isotope methodology of δD, δ18O, and δ13C was used to determine main water source and long-term water use efficiency of Salix psammophila and S. cheilophila, two dominant shrubs on interdune of alpine sandy land in northeastern Tibetan Plateau. The root systems of two Salix shrubs were investigated to determine their distribution pattern. The results showed that S. psammophila and S. cheilophila absorbed soil water at different soil depths or ground water in different seasons, depending on water availability and water use strategy. Salix psammophila used ground water during the growing season and relied on shallow soil water recharged by rain in summer. Salix cheilophila used ground water in spring and summer, but relied on shallow soil water recharged by rain in spring and deep soil water recharged by ground water in fall. The two shrubs had dimorphic root systems, which is coincident with their water use strategy. Higher biomass of fine roots in S. psammophila and longer fine roots in S. cheilophila facilitated to absorb water in deeper soil layers. The long-term water use efficiency of two Salix shrubs increased during the dry season in spring. The long-term water use efficiency was higher in S. psammophila than in S. cheilophila, as the former species is better adapted to semiarid climate of alpine sandy land. PMID:27243772
NASA Astrophysics Data System (ADS)
Juniah, Restu; Rahmi, Hisni
2017-11-01
Activities of sand mining on the surface stream (river) conducted by Panji Mahakarya company potentially cause various environmental issues. These problems include the destruction of the river ecosystem, decreased the quality of river water quality, increased water pollution load, and another effect on capacity and power support river. The Lambidaro River is one of the rivers found in Palembang, where the inhabitants who live around it take advantage of the existence of this river to meet their daily needs such as bathing, washing, and latrines. The purpose of this research is to know the influence of mining activities towards sustainability of the power support and capacity of the river. The method used in this research is to compare the availability of water and water needs of the population in determining the status of environmental power support based on regulation of the state minister of the environment number 17 in 2009 about the determination of the power guidance support environment in spatial regions, as well as using the index method of pollution based on the decision of the State Minister of the environment number 115 in 2003 about the determination of the status of water quality guidelines with parameters measured are TDS, TSS, pH, DO, COD, dan BOD5. The results of the calculation of the power support river are deficit where SA (34,200,655.64 m3/year) < DA (253,105,600 m3/year). The result of pollution index calculation at 5 water sampling locations shows that the condition of a river is in good condition (uncontaminated) and mild pollutant.
NASA Technical Reports Server (NTRS)
Whiteman, David N.; Venable, Demetrius D.; Walker, Monique; Cardirola, Martin; Sakai, Tetsu; Veselovskii, Igor
2013-01-01
Narrow-band detection of the Raman water vapor spectrum using the lidar technique introduces a concern over the temperature dependence of the Raman spectrum. Various groups have addressed this issue either by trying to minimize the temperature dependence to the point where it can be ignored or by correcting for whatever degree of temperature dependence exists. The traditional technique for performing either of these entails accurately measuring both the laser output wavelength and the water vapor spectral passband with combined uncertainty of approximately 0.01 nm. However, uncertainty in interference filter center wavelengths and laser output wavelengths can be this large or larger. These combined uncertainties translate into uncertainties in the magnitude of the temperature dependence of the Raman lidar water vapor measurement of 3% or more. We present here an alternate approach for accurately determining the temperature dependence of the Raman lidar water vapor measurement. This alternate approach entails acquiring sequential atmospheric profiles using the lidar while scanning the channel passband across portions of the Raman water vapor Q-branch. This scanning is accomplished either by tilt-tuning an interference filter or by scanning the output of a spectrometer. Through this process a peak in the transmitted intensity can be discerned in a manner that defines the spectral location of the channel passband with respect to the laser output wavelength to much higher accuracy than that achieved with standard laboratory techniques. Given the peak of the water vapor signal intensity curve, determined using the techniques described here, and an approximate knowledge of atmospheric temperature, the temperature dependence of a given Raman lidar profile can be determined with accuracy of 0.5% or better. A Mathematica notebook that demonstrates the calculations used here is available from the lead author.
Summary of hydrologic conditions of the Louisville area of Kentucky
Bell, Edwin Allen
1966-01-01
Water problems and their solutions have been associated with the growth and development of the Louisville area for more than a century. Many hydrologic data that aided water users in the past can be applied to present water problems and will be helpful for solving many similar problems in the future. Most of the water problems of Louisville, a water-rich area, concern management and are associated with the distribution of supplies, the quality of water, drainage, and waste disposal. The local hydrologic system at Louisville is dominated by the Ohio River and the glacial-outwash deposits beneath its flood plain. The water-bearing limestones in the uplands are ,secondary sources of water. The average flow of the Ohio River at Louisville, 73 billion gallons per day, and the potential availability of 370 million gallons per day of ground water suitable for industrial cooling purposes minimize the chance of acute water shortage in the area. Under current development, use of water averages about 211 million gallons per day, excluding about 392 million gallons of Ohio River water circulated daily through steampower plants and returned directly to the river. Optimum use and control of the water resources will be dependent on solving several water problems. The principal sources of water are in the Ohio River bottom land, whereas the new and potential centers of use are in the uplands. Either water must be piped to these new centers from the present sources or new supplies must be developed. Available data on streamflow and ground water are adequate to plan for the development of small local supplies. Since the completion of floodwalls and levees in 1953, widespread damage from flooding is a thing of the past in the Louisville area. Some local flooding of unprotected areas and of lowlands along tributary streams still takes place. The analyses of streamflow data are useful in planning for protection of these areas, but additional streamflow records and flood-area mapping are needed to best solve the problem. Droughts are a problem only to users of small water supplies in the uplands, where additional water either can be imported or developed locally. Pollution and undesirable chemical quality of water for some uses are the most serious drawbacks to the optimum development of the water resources in Louisville and Jefferson County. Available chemical analyses of ground water are useful for determining its suitability for various uses, but additional data are needed to guide management decisions. Sources of contamination should be inventoried and water samples analyzed periodically to monitor changes in quality.
Gas-film coefficients for streams
Rathbun, R.E.; Tai, D.Y.
1983-01-01
Equations for predicting the gas-film coefficient for the volatilization of organic solutes from streams are developed. The film coefficient is a function of windspeed and water temperature. The dependence of the coefficient on windspeed is determined from published information on the evaporation of water from a canal. The dependence of the coefficient on temperature is determined from laboratory studies on the evaporation of water. Procedures for adjusting the coefficients for different organic solutes are based on the molecular diffusion coefficient and the molecular weight. The molecular weight procedure is easiest to use because of the availability of molecular weights. However, the theoretical basis of the procedure is questionable. The diffusion coefficient procedure is supported by considerable data. Questions, however, remain regarding the exact dependence of the film coefficint on the diffusion coefficient. It is suggested that the diffusion coefficient procedure with a 0.68-power dependence be used when precise estimate of the gas-film coefficient are needed and that the molecular weight procedure be used when only approximate estimates are needed.
Geophysical survey for groundwater potential investigation in peat land area, Riau, Indonesia
NASA Astrophysics Data System (ADS)
Islami, N.; Irianti, M.; Azhar; Nor, M.; Fakhrudin
2018-04-01
Tropical forests, especially peat lands, are particularly vulnerable to forest fires. Fires are the most common disasters in peat lands in the dry season, especially in Riau Province, Indonesia. In the process of extinguishing the peat fire, several substantial problems arise to stop peat fires during this period. This study aims to determine the possibility of using ground water as a source of water to anticipate the early mitigation of peat land fires disaster. The geoelectrical resistivity surveys were used to predict the subsurface geological data including peat thickness and depth of aquifers. The geometry of peat lands was determined using geostatistics based on geoelectrical resistivity interpretation data. Peat Land thickness varies up to 4 m in the north and is thinner to the south. A shallower and deeper aquifer is available at a depth of 13 m to 18 m and 70 m to 90 m respectively. In general, the potential of groundwater in the shallow aquifer is predicted to be sufficient for peat land watering anytime.
NASA Astrophysics Data System (ADS)
Monaco, Eugenia; Bonfante, Antonello; De Mascellis, Roberto; Alfieri, Silvia Maria; Menenti, Massimo; De Lorenzi, Francesca
2013-04-01
Climate change will cause significant changes in water distribution and availability; as a consequence the water resources in some areas (like Mediterranean regions) will be limiting factors to the cultivation of some species, included cereals. So the perspective of climate change requires an analysis of the adaptation possibilities of food and fiber species currently cultivated. A powerful tool for adaptation is the relevant intra-specific biodiversity of crops. The knowledge, for different crop cultivars, of the responses to different environmental conditions (e.g. yield response functions to water regime) can be a tool to identify adaptation options to future climate. Moreover, simulation models of water flow in the soil-plant-atmosphere system can be coupled with future climate scenarios to predict the soil water regime also accounting for different irrigation scheduling options. In this work the adaptive capacity of maize hybrids (Zea mays L.) was evaluated in an irrigated district of Southern Italy (the "Destra Sele" plain, an area of about 18.000 ha), where maize is extensively grown for water buffalo feeding. Horticultural crops (tomato, fennel, artichoke) are grown, as well. The methodology applied is based on two complementary elements: - a database on climatic requirements of 30 maize hybrids: the yield response functions to water availability were determined from experimental data derived both from scientific literature and from field trials carried out by ISAFOM-CNR. These functions were applied to describe the behaviour of the hybrids with respect to the relative evapotranspiration deficit; - the simulation performed by the agro-hydrological model SWAP (soil-water-plant and atmosphere), to determine the future soil water regime at landscape scale. Two climate scenarios were studied: "past" (1961-1990) and "future" (2021-2050). Future climate scenarios were generated within the Italian National Project AGROSCENARI. Climate scenarios at low spatial resolution generated with general circulation models (AOGCMs) were down-scaled by means of a statistical model (Tomozeiu et al., 2007). The downscaled climate scenario includes 50 realizations of daily minimum, maximum temperature and precipitation data, on a regular grid with a spatial resolution of 35 km. The hydraulic properties of 25 representative soils of the "Destra Sele" area were estimated with HYPRES pedo-transfer function previously tested in the area. The model SWAP was run to determine the soil water balance with different irrigation strategies: optimal irrigation, no irrigation, and deficit irrigation, in both climate periods. Deficit irrigation was scheduled applying water volumes equal to 20%, 40%, 60% and 80% of optimal ones. From the outputs of the model runs the relative evapotranspiration deficit (or Crop Water Stress Index - CWSI) was calculated and compared with the yield response functions of the hybrids. By means of these functions, for each hybrid a critical value of CWSI was identified, namely a CWSI value corresponding to a relative yield of 0.9. By comparing the CWSI of soil units with hybrid's critical values, cultivar's adaptability to future water regime was determined, both as a function of irrigation scheduling and of soils' physical properties. The case study shows how, in the future climate scenario, with limited water resources, the intra-specific variability will allow to maintain current crop production system. The work was carried out within the Italian national project AGROSCENARI funded by the Ministry for Agricultural, Food and Forest Policies (MIPAAF, D.M. 8608/7303/2008)
Behavioral economic analysis of water intake in a laboratory rhesus macaque.
Wakita, Masumi
2004-10-01
Behavioral economics is useful for understanding the influence of environmental manipulation on a variety of behaviors, including drug self-administration, food intake, and stock behavior. The present study employed behavioral economics to investigate the psychologically satisfying amount of water intake in a laboratory rhesus macaque. Our institutional guidelines set a minimum amount of daily water intake. However, no study to date has determined whether that minimum amount is psychologically sufficient. In the present experiment, a monkey lived in an individual cage in which the only water available was delivered by chain pulling. A fixed number of responses was required for water delivery. This fixed ratio (FR) of responses per water delivery was progressively increased from FR 2 to FR 10. The study findings showed that during the FR 2 condition, demand for water was saturated at 131.3 ml/kg body weight (BW) (ranging from 95.1 to 211.2). The monkey's daily intake of water decreased as FR size incrementally increased, approaching an asymptote under the FR 8 and FR 10 conditions. During the FR 8 and FR 10 conditions, responding ceased when this monkey earned 53.5 ml/kg-BW (ranging from 32.7 to 74.9) of water. Therefore, the amount of water obtained under these conditions might provide a psychologically satisfying amount. Although these values were obtained from the behavioral study of one monkey, they were almost equivalent to values in our institutional guidelines that were determined by veterinary observations. These findings imply that behavioral economics is useful for studying the welfare of laboratory animals.
Chilled water study EEAP program for Walter Reed Army Medical Center: Book 2. Final report
DOE Office of Scientific and Technical Information (OSTI.GOV)
NONE
1996-02-01
The Energy Engineering Analysis Program (EEAP) Study for Walter Reed Army Medical Center (WRAMC) was to provide a thorough examination of the central chilled water plants on site. WRAMC is comprised of seventy-one (71) buildings located on a 113-acre site in Washington, D.C. There are two (2) central chilled water plants (Buildings 48 and 49) each with a primary chilled water distribution system. In addition to the two (2) central plants, three (3) buildings utilize their own independent chillers. Two (2) of the independent chillers (Buildings 7 and T-2), one of which is inoperative (T-2), are smaller air-cooled units, whilemore » the third (Building 54) has a 1,900-ton chilled water plant comprised of three (3) centrifugal chillers. Of the two (2) central chilled water plants, Building 48 houses six (6) chillers totalling 7,080 tons of cooling and Building 49 houses one (1) chiller with 660 tons of cooling. The total chiller cooling capacity available on site is 9,840 tons. The chilled water systems were reviewed for alternative ways of conserving energy on site and reducing the peak-cooling load. Distribution systems were reviewed to determine which buildings were served by each of the chilled water plants and to determine chilled water usage on site. Evaluations were made of building exterior and interior composition in order to estimate cooling loads. Interviews with site personnel helped Entech better understand the chilled water plants, the distribution systems, and how each system was utilized.« less
The economics of water reuse and implications for joint water quality-quantity management
NASA Astrophysics Data System (ADS)
Kuwayama, Y.
2015-12-01
Traditionally, economists have treated the management of water quality and water quantity as separate problems. However, there are some water management issues for which economic analysis requires the simultaneous consideration of water quality and quantity policies and outcomes. Water reuse, which has expanded significantly over the last several decades, is one of these issues. Analyzing the cost effectiveness and social welfare outcomes of adopting water reuse requires a joint water quality-quantity optimization framework because, at its most basic level, water reuse requires decision makers to consider (a) its potential for alleviating water scarcity, (b) the quality to which the water should be treated prior to reuse, and (c) the benefits of discharging less wastewater into the environment. In this project, we develop a theoretical model of water reuse management to illustrate how the availability of water reuse technologies and practices can lead to a departure from established rules in the water resource economics literature for the optimal allocation of freshwater and water pollution abatement. We also conduct an econometric analysis of a unique dataset of county-level water reuse from the state of Florida over the seventeen-year period between 1996 and 2012 in order to determine whether water quality or scarcity concerns drive greater adoption of water reuse practices.
NASA Astrophysics Data System (ADS)
Li, R.; Flyr, B.; Bradley, J.; Pun, M.; Schneider, J.; Wietjes, J.; Chinta, S.
2014-12-01
Determination of the nature and degree of hydrologically connected groundwater and surface water resources is of paramount importance to integrated water management within the State of Nebraska to understand the impact of water uses on available supplies, such as depletion of streams and aquifers caused by groundwater pumping. The ability to quantify effects of surface water-groundwater hydrologic connection and interactions, is regarded as one of the most important steps towards effectively managing water resources in Nebraska and provides the basis for designating management areas. Designation of management areas allows the state and other management entities to focus various efforts and resources towards those projects that have the greatest impact to water users. Nebraska Department of Natural Resources (NDNR) developed a groundwater modeling tool, Cycle Well Analysis, to determine the areas defined to have a high degree of connectivity between groundwater and surface water (in accordance with the state regulations). This tool features two graphic user interfaces to allow the analysis to be fully compatible with most MODFLOW-based numerical groundwater models currently utilized by NDNR. Case studies showed that the tool, in combination of Geographic Information Systems (GIS), can be used to quantify the degree of stream depletion and delineate the boundary of hydrologically connected areas within different political boundaries and subbasins in Nebraska. This approach may be applied to other regions with similar background and need for integrated water management.
Ground-water movement and nitrate in ground water, East Erda area, Tooele County, Utah, 1997-2000
Susong, D.D.
2005-01-01
Nitrate was discovered in ground water in the east Erda area of Tooele County, Utah, in 1994. The U.S. Geological Survey, in cooperation with Tooele County, investigated the ground-water flow system and water quality in the eastern part of Tooele Valley to determine (1) the vertical and horizontal distribution of nitrate, (2) the direction of movement of the nitrate contamination, and (3) the source of the nitrate. The potentiometric surface of the upper part of the basin-fill aquifer indicates that the general direction of ground-water flow is to the northwest, the flow system is complex, and there is a ground-water mound probably associated with springs. The spatial distribution of nitrate reflects the flow system with the nitrate contamination split into a north and south part by the ground-water mound. The distribution of dissolved solids and sulfate in ground water varies spatially. Vertical profiles of nitrate in water from selected wells indicate that nitrate contamination generally is in the upper part of the saturated zone and in some wells has moved downward. Septic systems, mining and smelting, agriculture, and natural sources were considered to be possible sources of nitrate contamination in the east Erda area. Septic systems are not the source of nitrate because water from wells drilled upgradient of all septic systems in the area had elevated nitrate concentrations. Mining and smelting activity are a possible source of nitrate contamination but few data are available to link nitrate contamination with mining sites. Natural and agricultural sources of nitrate are present east of the Erda area but few data are available about these sources. The source(s) of nitrate in the east Erda area could not be clearly delineated in spite of considerable effort and expenditure of resources.
NASA Astrophysics Data System (ADS)
Bartholomeus, R.; Witte, J.; van Bodegom, P.; Dam, J. V.; Aerts, R.
2010-12-01
With recent climate change, extremes in meteorological conditions are forecast and observed to increase globally, and to affect vegetation composition. More prolonged dry periods will alternate with more intensive rainfall events, both within and between years, which will change soil moisture dynamics. In temperate climates, soil moisture, in concert with nutrient availability and soil acidity, is the most important environmental filter in determining local plant species composition, as it determines the availability of both oxygen and water to plant roots. These resources are indispensable for meeting the physiological demands of plants. The consequences of climate change for our natural environment are among the most pressing issues of our time. The international research community is beginning to realise that climate extremes may be more powerful drivers of vegetation change and species extinctions than slow-and-steady climatic changes, but the causal mechanisms of such changes are presently unknown. The roles of amplitudes in water availability as drivers of vegetation change have been particularly elusive owing to the lack of integration of the key variables involved. Here we show that the combined effect of increased rainfall variability, temperature and atmospheric CO2-concentration will lead to an increased variability in both wet and dry extremes in stresses faced by plants (oxygen and water stress, respectively). We simulated these plant stresses with a novel, process-based approach, incorporating in detail the interacting processes in the soil-plant-atmosphere interface. In order to quantify oxygen and water stress with causal measures, we focused on interacting meteorological, soil physical, microbial, and plant physiological processes in the soil-plant-atmosphere system. As both the supply and demand of oxygen and water depend strongly on the prevailing meteorological conditions, both oxygen and water stress were calculated dynamically in time to capture climate change effects. We demonstrate that increased rainfall variability in interaction with predicted changes in temperature and CO2, affects soil moisture conditions and plant oxygen and water demands such, that both oxygen stress and water stress will intensify due to climate change. Moreover, these stresses will increasingly coincide, causing variable stress conditions. These variable stress conditions were found to decrease future habitat suitability, especially for plant species that are presently endangered. The future existence of such species is thus at risk by climate change, which has direct implications for policies to maintain endangered species, as applied by international nature management organisations (e.g. IUCN). Our integrated mechanistic analysis of two stresses combined, which has never been done so far, reveals large impacts of climate change on species extinctions and thereby on biodiversity.