Surface water-quality assessment of the lower Kansas River basin, Kansas and Nebraska: analysis of available water-quality data through 1986

USGS Publications Warehouse

Jordan, P.R.; Stamer, J.K.

1991-01-01

Beginning in 1986, the U.S. Congress 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 the full-scale program are to: (1) provide a nationally consistent description of current water-quality conditions for a large part of the Nation's surface- and ground-water resources; (2) define long-term trends (or lack of trends) in water quality; and (3) identify, describe, and explain, insofar as possible, the major factors that affect current conditions and trends in water quality. This information, obtained on a continuing basis, will be made available to water managers, policy makers, and the public to provide an improved scientific basis for evaluating the effectiveness of water-quality-management programs and for predicting the likely effects of contemplated changes in land-and water-management practices. At present (1990), the assessment program is in a pilot phase in seven areas that represent diverse hydrologic environments and water-quality conditions.This report completes one of the first activities undertaken as part of the lower Kansas River basin pilot study, which was to compile, screen, and interpret available water-quality data for the study unit through 1986. The report includes information on the sources and types of water-quality data available, the utility of available water-quality data for assessment purposes, and a description of current water-quality conditions and trends and their relation to natural and human factors.

Open Source Tools for Assessment of Global Water Availability, Demands, and Scarcity

NASA Astrophysics Data System (ADS)

Li, X.; Vernon, C. R.; Hejazi, M. I.; Link, R. P.; Liu, Y.; Feng, L.; Huang, Z.; Liu, L.

2017-12-01

Water availability and water demands are essential factors for estimating water scarcity conditions. To reproduce historical observations and to quantify future changes in water availability and water demand, two open source tools have been developed by the JGCRI (Joint Global Change Research Institute): Xanthos and GCAM-STWD. Xanthos is a gridded global hydrologic model, designed to quantify and analyze water availability in 235 river basins. Xanthos uses a runoff generation and a river routing modules to simulate both historical and future estimates of total runoff and streamflows on a monthly time step at a spatial resolution of 0.5 degrees. GCAM-STWD is a spatiotemporal water disaggregation model used with the Global Change Assessment Model (GCAM) to spatially downscale global water demands for six major enduse sectors (irrigation, domestic, electricity generation, mining, and manufacturing) from the region scale to the scale of 0.5 degrees. GCAM-STWD then temporally downscales the gridded annual global water demands to monthly results. These two tools, written in Python, can be integrated to assess global, regional or basin-scale water scarcity or water stress. Both of the tools are extensible to ensure flexibility and promote contribution from researchers that utilize GCAM and study global water use and supply.

Is the available cropland and water enough for food demand? A global perspective of the Land-Water-Food nexus

NASA Astrophysics Data System (ADS)

Ibarrola-Rivas, M. J.; Granados-Ramírez, R.; Nonhebel, S.

2017-12-01

Land and water are essential local resources for food production but are limited. The main drivers of increasing food demand are population growth and dietary changes, which depend on the socioeconomic situation of the population. These two factors affect the availability of local resources: population growth reduces the land and water per person; and adoption of affluent diets increases the demand for land and water per person. This study shows potentials of global food supply by linking food demand drivers with national land and water availability. Whether the available land and water is enough to meet national food demand was calculated for 187 countries. The calculations were performed for the past situation (1960 and 2010) and to assess four future scenarios (2050) to discuss different paths of diets, population numbers and agricultural expansion. Inclusion of the demand perspective in the analysis has shown stronger challenges for future global food supply than have other studies. The results show that with the "business as usual" scenario, 40% of the global population in 2050 will live in countries with not enough land nor water to meet the demands of their population. Restriction to basic diets will be the most effective in lowering both land and water constraints. Our results identify both food production and food demand factors, and the regions that may experience the strongest challenges in 2050.

User manuals for the Delaware River Basin Water Availability Tool for Environmental Resources (DRB–WATER) and associated WATER application utilities

USGS Publications Warehouse

Williamson, Tanja N.; Lant, Jeremiah G.

2015-11-18

The Water Availability Tool for Environmental Resources (WATER) is a decision support system (DSS) for the nontidal part of the Delaware River Basin (DRB) that provides a consistent and objective method of simulating streamflow under historical, forecasted, and managed conditions. WATER integrates geospatial sampling of landscape characteristics, including topographic and soil properties, with a regionally calibrated hillslope-hydrology model, an impervious-surface model, and hydroclimatic models that have been parameterized using three hydrologic response units—forested, agricultural, and developed land cover. It is this integration that enables the regional hydrologic-modeling approach used in WATER without requiring site-specific optimization or those stationary conditions inferred when using a statistical model. The DSS provides a “historical” database, ideal for simulating streamflow for 2001–11, in addition to land-cover forecasts that focus on 2030 and 2060. The WATER Application Utilities are provided with the DSS and apply change factors for precipitation, temperature, and potential evapotranspiration to a 1981–2011 climatic record provided with the DSS. These change factors were derived from a suite of general circulation models (GCMs) and representative concentration pathway (RCP) emission scenarios. These change factors are based on 25-year monthly averages (normals) that are centere on 2030 and 2060. The WATER Application Utilities also can be used to apply a 2010 snapshot of water use for the DRB; a factorial approach enables scenario testing of increased or decreased water use for each simulation. Finally, the WATER Application Utilities can be used to reformat streamflow time series for input to statistical or reservoir management software. 

Water Availability for the Western United States - Key Scientific Challenges

USGS Publications Warehouse

Anderson, Mark Theodore; Woosley, Lloyd H.

2005-01-01

users in the West is that these reserved rights may supersede other existing users. The minimum amount of water required, however, to sustain native peoples, a riparian system, or an endangered species eventually will need to be known in order to manage the available water supply. Periodic inventory and assessment of the amounts and trends of water available in surface water and ground water are needed to support water management. There is a widespread perception that the amount of available water is diminishing with time. This and other perceptions about water availability should be replaced by objective data and analysis. Some data are presented here for the major Western rivers that show that flows are not decreasing in most streams and rivers in the West. Systematic information is lacking to make broad assessments of ground-water availability, but available data for specific aquifers indicate that these aquifers are being depleted, especially near population centers. The complexity added to the issue of Western water availability by these and other factors gives rise to a significant role of science. Science has played a role in support of Western water development from the beginning, and the role has evolved and changed over time as society's values have changed. In this report, the role of science is discussed in three phases: (1) development and construction, (2) consequences and environmental awareness, and (3) sustainability. The development and construction phase includes some historical accounting of water development in the West and shows how some precedents set in those early days are still applied today. Science has played an important role in the second phase by objectively pointing out the consequences of this development and construction phase, such as the effects from converting rivers to reservoirs, the effects of ground-water pumping on surface water in streams, land-surface subsidence, and the changes in water quality brought about by the dispo

46 CFR 76.10-3 - Water availability.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 3 2010-10-01 2010-10-01 false Water availability. 76.10-3 Section 76.10-3 Shipping... Fire Main System, Details § 76.10-3 Water availability. (a) On all vessels on an international voyage, regardless of the date of construction, water pressure from the firemain protecting enclosed spaces shall be...

46 CFR 76.10-3 - Water availability.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 3 2011-10-01 2011-10-01 false Water availability. 76.10-3 Section 76.10-3 Shipping... Fire Main System, Details § 76.10-3 Water availability. (a) On all vessels on an international voyage, regardless of the date of construction, water pressure from the firemain protecting enclosed spaces shall be...

46 CFR 76.10-3 - Water availability.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 3 2014-10-01 2014-10-01 false Water availability. 76.10-3 Section 76.10-3 Shipping... Fire Main System, Details § 76.10-3 Water availability. (a) On all vessels on an international voyage, regardless of the date of construction, water pressure from the firemain protecting enclosed spaces shall be...

46 CFR 76.10-3 - Water availability.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 3 2013-10-01 2013-10-01 false Water availability. 76.10-3 Section 76.10-3 Shipping... Fire Main System, Details § 76.10-3 Water availability. (a) On all vessels on an international voyage, regardless of the date of construction, water pressure from the firemain protecting enclosed spaces shall be...

46 CFR 76.10-3 - Water availability.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 3 2012-10-01 2012-10-01 false Water availability. 76.10-3 Section 76.10-3 Shipping... Fire Main System, Details § 76.10-3 Water availability. (a) On all vessels on an international voyage, regardless of the date of construction, water pressure from the firemain protecting enclosed spaces shall be...

Shifts in water availability mediate plant-pollinator interactions.

PubMed

Gallagher, M Kate; Campbell, Diane R

2017-07-01

Altered precipitation patterns associated with anthropogenic climate change are expected to have many effects on plants and insect pollinators, but it is unknown if effects on pollination are mediated by changes in water availability. We tested the hypothesis that impacts of climate on plant-pollinator interactions operate through changes in water availability, and specifically that such effects occur through alteration of floral attractants. We manipulated water availability in two naturally occurring Mertensia ciliata (Boraginaceae) populations using water addition, water reduction and control plots and measured effects on vegetative and floral traits, pollinator visitation and seed set. While most floral trait values, including corolla size and nectar, increased linearly with increasing water availability, in this bumblebee-pollinated species, pollinator visitation peaked at intermediate water levels. Visitation also peaked at an intermediate corolla length, while its relationship to corolla width varied across sites. Seed set, however, increased linearly with water. These results demonstrate the potential for changes in water availability to impact plant-pollinator interactions through pollinator responses to differences in floral attractants, and that the effects of water on pollinator visitation can be nonlinear. Plant responses to changes in resource availability may be an important mechanism by which climate change will affect species interactions. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

Endogenous change: on cooperation and water availability in two ancient societies

NASA Astrophysics Data System (ADS)

Pande, S.; Ertsen, M.

2014-05-01

We propose and test the theory of endogenous change in societal institutions based on historical reconstructions of two ancient civilizations, the Indus and Hohokam, in two water-scarce basins, the Indus Basin in the Indian subcontinent and the lower Colorado Basin in the southwestern United States. In our reconstructions, institutions are approximated by the scale of "cooperation", be it in the form of the extent of trade, sophisticated irrigation networks, a central state or a loosely held state with a common cultural identity. We study changes in institutions brought about by changes in factors like rainfall, population density, and land-use-induced water resource availability, in a proximate manner. These factors either change naturally or are changed by humans; in either case we contend that the changes affect the stability of cooperative structures over time. We relate the quantitative dimensions of water access by ancient populations to the co-evolution of water access and the socioeconomic and sociopolitical organizations. In doing so, we do not claim that water manipulation was the single most significant factor in stimulating social development and complexity - this would be highly reductionist. Nonetheless, we provide a discussion with the aim to enhance our understanding of the complexity of coupled human-hydrological systems. We find that scarcity triggered more complex cooperative arrangements in both Indus and Hohokam societies.

Water on Mars - Volatile history and resource availability

NASA Technical Reports Server (NTRS)

Jakosky, Bruce M.

1990-01-01

An attempt is made to define the available deposits of water in the near-surface region of Mars which will be available to human exploration missions. The Martian seasonal water cycle is reviewed, and geochemical and geological constraints on the availability of water are examined. It is concluded that the only sure source of water in amounts significant as a resource are in the polar ice deposits.

Water Availability and Management of Water Resources

EPA Science Inventory

One of the most pressing national and global issues is the availability of freshwater due to global climate change, energy scarcity issues and the increase in world population and accompanying economic growth. Estimates of water supplies and flows through the world's hydrologic c...

Water Availability in a Warming World

NASA Astrophysics Data System (ADS)

Aminzade, Jennifer

As climate warms during the 21st century, the resultant changes in water availability are a vital issue for society, perhaps even more important than the magnitude of warming itself. Yet our climate models disagree in their forecasts of water availability, limiting our ability to plan accordingly. This thesis investigates future water availability projections from Coupled Ocean-Atmosphere General Circulation Models (GCMs), primarily using two water availability measures: soil moisture and the Supply Demand Drought Index (SDDI). Chapter One introduces methods of measuring water availability and explores some of the fundamental differences between soil moisture, SDDI and the Palmer Drought Severity Index (PDSI). SDDI and PDSI tend to predict more severe future drought conditions than soil moisture; 21st century projections of SDDI show conditions rivaling North American historic mega-droughts. We compare multiple potential evapotranspiration (EP) methods in New York using input from the GISS Model ER GCM and local station data from Rochester, NY, and find that they compare favorably with local pan evaporation measurements. We calculate SDDI and PDSI values using various EP methods, and show that changes in future projections are largest when using EP methods most sensitive to global warming, not necessarily methods producing EP values with the largest magnitudes. Chapter Two explores the characteristics and biases of the five GCMs and their 20th and 21st century climate projections. We compare atmospheric variables that drive water availability changes globally, zonally, and geographically among models. All models show increases in both dry and wet extremes for SDDI and soil moisture, but increases are largest for extreme drying conditions using SDDI. The percentage of gridboxes that agree on the sign of change of soil moisture and SDDI between models is very low, but does increase in the 21st century. Still, differences between models are smaller than differences

Water availability and management for food security

USDA-ARS?s Scientific Manuscript database

Food security is directly linked to water security for food production. Water availability for crop production will be dependent upon precipitation or irrigation, soil water holding capacity, and crop water demand. The linkages among these components in rainfed agricultural systems shows the impact ...

Drought, Land-Use Change, and Water Availability in California's Central Valley

NASA Astrophysics Data System (ADS)

Faunt, C. C.; Sneed, M.; Traum, J.

2015-12-01

The Central Valley is a broad alluvial-filled structural trough that covers about 52,000 square kilometers and is one of the most productive agricultural regions in the world. Because the valley is semi-arid and the availability of surface water varies substantially from year to year, season to season, and from north to south, agriculture developed a reliance on groundwater for irrigation. During recent drought periods (2007-09 and 2012-present), groundwater pumping has increased due to a combination of factors including drought and land-use changes. In response, groundwater levels have declined to levels approaching or below historical low levels. In the San Joaquin Valley, the southern two thirds of the Central Valley, the extensive groundwater pumpage has caused aquifer system compaction, resulting in land subsidence and permanent loss of groundwater storage capacity. The magnitude and rate of subsidence varies based on geologic materials, consolidation history, and historical water levels. Spatially-variable subsidence has changed the land-surface slope, causing operational, maintenance, and construction-design problems for surface-water infrastructure. It is important for water agencies to plan for the effects of continued water-level declines, storage losses, and/or land subsidence. To combat these effects, excess surface water, when available, is artificially recharged. As surface-water availability, land use, and artificial recharge continue to vary, long-term groundwater-level and land-subsidence monitoring and modelling are critical to understanding the dynamics of the aquifer system. Modeling tools, such as the Central Valley Hydrologic Model, can be used in the analysis and evaluation of management strategies to mitigate adverse impacts due to subsidence, while also optimizing water availability. These analyses will be critical for successful implementation of recent legislation aimed toward sustainable groundwater use.

Proposing water balance method for water availability estimation in Indonesian regional spatial planning

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.

Analysis of the Development of Available Soil Water Storage in the Nitra River Catchment

NASA Astrophysics Data System (ADS)

Tárník, Andrej; Leitmanová, Mária

2017-10-01

World is changing dramatically. Every sphere of our life is influenced by global climate changes, including agriculture sector. Rising air temperature and temporal variability of rainfall are crucial outcomes of climate changes for agricultural activities. Main impact of these outcomes on agriculture is the change of soil water amount. Soil water is an exclusive resource of water for plants. Changes of soil water storage are sensed very sensitively by farmers. Development of soil water storage was analysed in this paper. The Nitra River catchment is covered by nets of hydrological and meteorological stations of Department of Biometeorology and Hydrology, Slovak University of Agriculture in Nitra. Quantity of available soil water storage for plants was calculated every month in the years from 2013 to 2016. Calculations were done based on real measurements for soil horizon 0-30 cm. Ratio between a real available soil water storage and a potential available soil water storage was specified. Amount of potential available soil water storage was derived by retention curves of soil samples. Map of risk areas was created in GIS in pursuance of these calculations. We can see the negative trends of available soil water storage in years 2015 and 2016. Main addition of this paper is a selection of areas where soil moisture is a limiting factor of agriculture. In these areas, it is necessary to do the mitigation measures for sustainable development of agricultural activities.

A Review of Operational Water Consumption and Withdrawal Factors for Electricity Generating Technologies

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

Macknick, Jordan; Newmark, Robin; Heath, Garvin

2011-03-01

This report provides estimates of operational water withdrawal and water consumption factors for electricity generating technologies in the United States. Estimates of water factors were collected from published primary literature and were not modified except for unit conversions. The presented water factors may be useful in modeling and policy analyses where reliable power plant level data are not available.

Compounding Impacts of Human-Induced Water Stress and Climate Change on Water Availability.

PubMed

Mehran, Ali; AghaKouchak, Amir; Nakhjiri, Navid; Stewardson, Michael J; Peel, Murray C; Phillips, Thomas J; Wada, Yoshihide; Ravalico, Jakin K

2017-07-24

The terrestrial phase of the water cycle can be seriously impacted by water management and human water use behavior (e.g., reservoir operation, and irrigation withdrawals). Here we outline a method for assessing water availability in a changing climate, while explicitly considering anthropogenic water demand scenarios and water supply infrastructure designed to cope with climatic extremes. The framework brings a top-down and bottom-up approach to provide localized water assessment based on local water supply infrastructure and projected water demands. When our framework is applied to southeastern Australia we find that, for some combinations of climatic change and water demand, the region could experience water stress similar or worse than the epic Millennium Drought. We show considering only the influence of future climate on water supply, and neglecting future changes in water demand and water storage augmentation might lead to opposing perspectives on future water availability. While human water use can significantly exacerbate climate change impacts on water availability, if managed well, it allows societies to react and adapt to a changing climate. The methodology we present offers a unique avenue for linking climatic and hydrologic processes to water resource supply and demand management and other human interactions.

Compounding Impacts of Human-Induced Water Stress and Climate Change on Water Availability

NASA Technical Reports Server (NTRS)

Mehran, Ali; AghaKouchak, Amir; Nakhjiri, Navid; Stewardson, Michael J.; Peel, Murray C.; Phillips, Thomas J.; Wada, Yoshihide; Ravalico, Jakin K.

2017-01-01

The terrestrial phase of the water cycle can be seriously impacted by water management and human water use behavior (e.g., reservoir operation, and irrigation withdrawals). Here we outline a method for assessing water availability in a changing climate, while explicitly considering anthropogenic water demand scenarios and water supply infrastructure designed to cope with climatic extremes. The framework brings a top-down and bottom-up approach to provide localized water assessment based on local water supply infrastructure and projected water demands. When our framework is applied to southeastern Australia we find that, for some combinations of climatic change and water demand, the region could experience water stress similar or worse than the epic Millennium Drought. We show considering only the influence of future climate on water supply, and neglecting future changes in water demand and water storage augmentation might lead to opposing perspectives on future water availability. While human water use can significantly exacerbate climate change impacts on water availability, if managed well, it allows societies to react and adapt to a changing climate. The methodology we present offers a unique avenue for linking climatic and hydrologic processes to water resource supply and demand management and other human interactions.

Effect of water availability in opening containers of breeding site on Aedes aegypti life cycle

NASA Astrophysics Data System (ADS)

Tokachil, Najir; Yusoff, Nuraini; Saaid, Alif; Appandi, Najwa; Harun, Farhana

2017-11-01

The distribution of rainfall is one of the factors which contribute to the development of Aedes aegypti life cycle. The fluctuation of rainfall might influence the acceleration of Aedes aegypti growth by providing sufficient breeding sites. In this research, the availability of water in an opening container of the breeding site is considered as a significant variable which affects the distinct stages structure in mosquito life cycle which egg, larva, pupa, and adult. A stage-structured Lefkovitch matrix model was used by considering the quantity of water contains in an opening container and life cycle of Aedes aegypti. The maximum depth of water in the container was also taken into account in order to find the time duration of mosquito life cycle to complete. We found that the maximum depth of water availability in mosquito breeding site influenced the abundance of the mosquito population. Hence, the containers are filled with sufficient water be able to stand from hot temperature for several days before drying out might continue to provide mosquito breeding site. In the future, it is recommended to consider other factors which affect the quantity of water in mosquito breeding sites such as heavy rain and wind blows.

Urban water metabolism efficiency assessment: integrated analysis of available and virtual water.

PubMed

Huang, Chu-Long; Vause, Jonathan; Ma, Hwong-Wen; Yu, Chang-Ping

2013-05-01

Resolving the complex environmental problems of water pollution and shortage which occur during urbanization requires the systematic assessment of urban water metabolism efficiency (WME). While previous research has tended to focus on either available or virtual water metabolism, here we argue that the systematic problems arising during urbanization require an integrated assessment of available and virtual WME, using an indicator system based on material flow analysis (MFA) results. Future research should focus on the following areas: 1) analysis of available and virtual water flow patterns and processes through urban districts in different urbanization phases in years with varying amounts of rainfall, and their environmental effects; 2) based on the optimization of social, economic and environmental benefits, establishment of an indicator system for urban WME assessment using MFA results; 3) integrated assessment of available and virtual WME in districts with different urbanization levels, to facilitate study of the interactions between the natural and social water cycles; 4) analysis of mechanisms driving differences in WME between districts with different urbanization levels, and the selection of dominant social and economic driving indicators, especially those impacting water resource consumption. Combinations of these driving indicators could then be used to design efficient water resource metabolism solutions, and integrated management policies for reduced water consumption. Copyright © 2013 Elsevier B.V. All rights reserved.

Compounding Impacts of Human-Induced Water Stress and Climate Change on Water Availability

DOE PAGES

Mehran, Ali; AghaKouchak, Amir; Nakhjiri, Navid; ...

2017-07-24

The terrestrial phase of the water cycle can be seriously impacted by water management and human water use behavior (e.g., reservoir operation, and irrigation withdrawals). Here we outline a method for assessing water availability in a changing climate, while explicitly considering anthropogenic water demand scenarios and water supply infrastructure designed to cope with climatic extremes. The framework brings a top-down and bottom-up approach to provide localized water assessment based on local water supply infrastructure and projected water demands. When our framework is applied to southeastern Australia we find that, for some combinations of climatic change and water demand, the regionmore » could experience water stress similar or worse than the epic Millennium Drought. We show considering only the influence of future climate on water supply, and neglecting future changes in water demand and water storage augmentation might lead to opposing perspectives on future water availability. While human water use can significantly exacerbate climate change impacts on water availability, if managed well, it allows societies to react and adapt to a changing climate. The methodology we present offers a unique avenue for linking climatic and hydrologic processes to water resource supply and demand management and other human interactions.« less

Compounding Impacts of Human-Induced Water Stress and Climate Change on Water Availability

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

Mehran, Ali; AghaKouchak, Amir; Nakhjiri, Navid

The terrestrial phase of the water cycle can be seriously impacted by water management and human water use behavior (e.g., reservoir operation, and irrigation withdrawals). Here we outline a method for assessing water availability in a changing climate, while explicitly considering anthropogenic water demand scenarios and water supply infrastructure designed to cope with climatic extremes. The framework brings a top-down and bottom-up approach to provide localized water assessment based on local water supply infrastructure and projected water demands. When our framework is applied to southeastern Australia we find that, for some combinations of climatic change and water demand, the regionmore » could experience water stress similar or worse than the epic Millennium Drought. We show considering only the influence of future climate on water supply, and neglecting future changes in water demand and water storage augmentation might lead to opposing perspectives on future water availability. While human water use can significantly exacerbate climate change impacts on water availability, if managed well, it allows societies to react and adapt to a changing climate. The methodology we present offers a unique avenue for linking climatic and hydrologic processes to water resource supply and demand management and other human interactions.« less

Biological Stability of Drinking Water: Controlling Factors, Methods, and Challenges.

PubMed

Prest, Emmanuelle I; Hammes, Frederik; van Loosdrecht, Mark C M; Vrouwenvelder, Johannes S

2016-01-01

Biological stability of drinking water refers to the concept of providing consumers with drinking water of same microbial quality at the tap as produced at the water treatment facility. However, uncontrolled growth of bacteria can occur during distribution in water mains and premise plumbing, and can lead to hygienic (e.g., development of opportunistic pathogens), aesthetic (e.g., deterioration of taste, odor, color) or operational (e.g., fouling or biocorrosion of pipes) problems. Drinking water contains diverse microorganisms competing for limited available nutrients for growth. Bacterial growth and interactions are regulated by factors, such as (i) type and concentration of available organic and inorganic nutrients, (ii) type and concentration of residual disinfectant, (iii) presence of predators, such as protozoa and invertebrates, (iv) environmental conditions, such as water temperature, and (v) spatial location of microorganisms (bulk water, sediment, or biofilm). Water treatment and distribution conditions in water mains and premise plumbing affect each of these factors and shape bacterial community characteristics (abundance, composition, viability) in distribution systems. Improved understanding of bacterial interactions in distribution systems and of environmental conditions impact is needed for better control of bacterial communities during drinking water production and distribution. This article reviews (i) existing knowledge on biological stability controlling factors and (ii) how these factors are affected by drinking water production and distribution conditions. In addition, (iii) the concept of biological stability is discussed in light of experience with well-established and new analytical methods, enabling high throughput analysis and in-depth characterization of bacterial communities in drinking water. We discussed, how knowledge gained from novel techniques will improve design and monitoring of water treatment and distribution systems in order

Biological Stability of Drinking Water: Controlling Factors, Methods, and Challenges

PubMed Central

Prest, Emmanuelle I.; Hammes, Frederik; van Loosdrecht, Mark C. M.; Vrouwenvelder, Johannes S.

2016-01-01

Biological stability of drinking water refers to the concept of providing consumers with drinking water of same microbial quality at the tap as produced at the water treatment facility. However, uncontrolled growth of bacteria can occur during distribution in water mains and premise plumbing, and can lead to hygienic (e.g., development of opportunistic pathogens), aesthetic (e.g., deterioration of taste, odor, color) or operational (e.g., fouling or biocorrosion of pipes) problems. Drinking water contains diverse microorganisms competing for limited available nutrients for growth. Bacterial growth and interactions are regulated by factors, such as (i) type and concentration of available organic and inorganic nutrients, (ii) type and concentration of residual disinfectant, (iii) presence of predators, such as protozoa and invertebrates, (iv) environmental conditions, such as water temperature, and (v) spatial location of microorganisms (bulk water, sediment, or biofilm). Water treatment and distribution conditions in water mains and premise plumbing affect each of these factors and shape bacterial community characteristics (abundance, composition, viability) in distribution systems. Improved understanding of bacterial interactions in distribution systems and of environmental conditions impact is needed for better control of bacterial communities during drinking water production and distribution. This article reviews (i) existing knowledge on biological stability controlling factors and (ii) how these factors are affected by drinking water production and distribution conditions. In addition, (iii) the concept of biological stability is discussed in light of experience with well-established and new analytical methods, enabling high throughput analysis and in-depth characterization of bacterial communities in drinking water. We discussed, how knowledge gained from novel techniques will improve design and monitoring of water treatment and distribution systems in order

The potential impacts of biomass feedstock production on water resource availability.

PubMed

Stone, K C; Hunt, P G; Cantrell, K B; Ro, K S

2010-03-01

Biofuels are a major topic of global interest and technology development. Whereas bioenergy crop production is highly dependent on water, bioenergy development requires effective allocation and management of water. The objectives of this investigation were to assess the bioenergy production relative to the impacts on water resource related factors: (1) climate and weather impact on water supplies for biomass production; (2) water use for major bioenergy crop production; and (3) potential alternatives to improve water supplies for bioenergy. Shifts to alternative bioenergy crops with greater water demand may produce unintended consequences for both water resources and energy feedstocks. Sugarcane and corn require 458 and 2036 m(3) water/m(3) ethanol produced, respectively. The water requirements for corn grain production to meet the US-DOE Billion-Ton Vision may increase approximately 6-fold from 8.6 to 50.1 km(3). Furthermore, climate change is impacting water resources throughout the world. In the western US, runoff from snowmelt is occurring earlier altering the timing of water availability. Weather extremes, both drought and flooding, have occurred more frequently over the last 30 years than the previous 100 years. All of these weather events impact bioenergy crop production. These events may be partially mitigated by alternative water management systems that offer potential for more effective water use and conservation. A few potential alternatives include controlled drainage and new next-generation livestock waste treatment systems. Controlled drainage can increase water available to plants and simultaneously improve water quality. New livestock waste treatments systems offer the potential to utilize treated wastewater to produce bioenergy crops. New technologies for cellulosic biomass conversion via thermochemical conversion offer the potential for using more diverse feedstocks with dramatically reduced water requirements. The development of bioenergy

Ground-water quality assessment of the central Oklahoma aquifer, Oklahoma - Analysis of available water-quality data through 1987

USGS Publications Warehouse

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

Relative controls of natural and socio-economic drivers on water availability over India: an exploratory modelling analysis

NASA Astrophysics Data System (ADS)

Deshmukh, A.; Singh, R.; Kumar, R.

2017-12-01

India, a water stressed nation with an estimated per capita water availability of 1500m3/year/person, is projected to surpass China in population to become the most populous country by 2022. This increasing population will further exacerbate the water stress, which will also vary due to climate and land use change. Here, we quantify the relative controls on per capita water availability from climatic, non-climatic and socio-economic factors. We achieve this by using several definitions of per capita water availability and accounting for virtual water trade transfer. Our exploratory analysis employs the recently developed probabilistic Budyko framework modified to account for inter-regional virtual water trade. We find that the Indo-Gangetic plains and Southeastern parts of India emerge as vulnerable regions where a growing population will lead to a drastic reduction in per capita water availability. The proposed framework can serve as a prototype for understanding the relative importance of socio-economic interventions versus water infrastructure or demand reduction investments.

Topographic, edaphic, and vegetative controls on plant-available water

USGS Publications Warehouse

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.

Studies on kinetics of water quality factors to establish water transparency model in Neijiang River, China.

PubMed

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.

Soil Water Availability Modulation Over Estimated Relative Yield Losses in Wheat (Triticum aestivum L.) Due to Ozone Exposure

PubMed Central

De la Torre, Daniel; Sierra, Maria Jose

2007-01-01

The approach developed by Fuhrer in 1995 to estimate wheat yield losses induced by ozone and modulated by the soil water content (SWC) was applied to the data on Catalonian wheat yields. The aim of our work was to apply this approach and adjust it to Mediterranean environmental conditions by means of the necessary corrections. The main objective pursued was to prove the importance of soil water availability in the estimation of relative wheat yield losses as a factor that modifies the effects of tropospheric ozone on wheat, and to develop the algorithms required for the estimation of relative yield losses, adapted to the Mediterranean environmental conditions. The results show that this is an easy way to estimate relative yield losses just using meteorological data, without using ozone fluxes, which are much more difficult to calculate. Soil water availability is very important as a modulating factor of the effects of ozone on wheat; when soil water availability decreases, almost twice the amount of accumulated exposure to ozone is required to induce the same percentage of yield loss as in years when soil water availability is high. PMID:17619747

When vegetation change alters ecosystem water availability

USDA-ARS?s Scientific Manuscript database

The combined effects of vegetation and climate change on biosphere-atmosphere water vapor (H2O) and carbon dioxide (CO2) exchanges are expected to vary depending, in part, on how biotic activity is controlled by and alters water availability. This is particularly important when a change in ecosystem...

78 FR 27233 - Clean Water Act: Availability of List Decisions

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-09

... ENVIRONMENTAL PROTECTION AGENCY [FRL-9811-4] Clean Water Act: Availability of List Decisions... announces the availability of EPA's action identifying water quality limited segments and associated pollutants in Louisiana to be listed pursuant to Clean Water Act Section 303(d), and request for public...

Cell and tissue dynamics of olive endocarp sclerification vary according to water availability.

PubMed

Hammami, Sofiene B M; Costagli, Giacomo; Rapoport, Hava F

2013-12-01

Endocarp developmental timing in drupe-type fruits, involving tissue expansion and sclerification processes, is increasingly used as marker for biological studies and crop management. In spite of its wide application, however, little is known regarding how these morphogenetic processes unfold or the factors that modify it. This study evaluates endocarp expansion and sclerification of olive (Olea europaea) fruits, used as an example of drupe-type fruits, from trees growing under different water regimes: full irrigated, deficit irrigated (moderate reduction of water availability) and rainfed (severe reduction of water availability). Fruits were sampled weekly until pit hardening, and fruit and endocarp areas were evaluated in histological preparations. An image analysis process was tested and adjusted to quantify sclerified area and distribution within the endocarp. Individual stone cells differentiated independently but distribution and timing indicated the overall coordination of endocarp tissue sclerification. Increase in sclerified area was initially gradual, accelerated abruptly the week prior to the end of endocarp expansion and then continued at an intermediate rate. These results suggest that the end of the expansion period is driven by sclerification and the morphogenetic signals involved act first on sclerification rather than endocarp size. Intensification of sclerification and the end of expansive growth occurred first with lowest water supply. Moderate and severe reductions in water availability proportionately decreased endocarp expansion and prolonged the sclerification, delaying the date of physically perceived hardening but not affecting the final degree of endocarp sclerification. © 2013 Scandinavian Plant Physiology Society.

Availability of Water in the Kabul Basin, Afghanistan

USGS Publications Warehouse

Mack, Thomas J.; Chornack, Michael P.; Coplen, T.B.; Plummer, Niel; Rezai, M.T.; Verstraeten, Ingrid M.

2010-01-01

The availability of water resources is vital to the social and economic well being and rebuilding of Afghanistan. Kabul City currently (2010) has a population of nearly 4 million and is growing rapidly as a result of periods of relative security and the return of refugees. Population growth and recent droughts have placed new stresses on the city's limited water resources and have caused many wells to become contaminated, dry, or inoperable in recent years. The projected vulnerability of Central and West Asia to climate change (Cruz and others, 2007; Milly and others, 2005) and observations of diminishing glaciers in Afghanistan (Molnia, 2009) have heightened concerns for future water availability in the Kabul Basin of Afghanistan.

Geospatial variation of grapevine water status, soil water availability, grape composition and sensory characteristics in a spatially heterogeneous premium wine grape vineyard

NASA Astrophysics Data System (ADS)

Smart, D. R.; Cosby Hess, S.; Plant, R.; Feihn, O.; Heymann, H.; Ebeler, S.

2014-11-01

The geoscience component of terroir in wine grape production continues to be criticized for its quasi-mystical nature, and lack of testable hypotheses. Nonetheless, recent relational investigations are emerging and most involve water availability as captured by available water capacity (AWC, texture) or plant available water (PAW) in the root zone of soil as being a key factor. The second finding emerging may be that the degree of microscale variability in PAW and other soil factors at the vineyard scale renders larger regional characterizations questionable. Cimatic variables like temperature are well mixed, and its influence on wine characteristic is fairly well established. The influence of mesogeology on mesoclimate factors has also been characterized to some extent. To test the hypothesis that vine water status mirrors soil water availability, and controls fruit sensory and chemical properties at the vineyard scale we examined such variables in a iconic, selectively harvested premium winegrape vineyard in the Napa Valley of California during 2007 and 2008 growing seasons. Geo-referenced data vines remained as individual study units throughout data gathering and analysis. Cartographic exercises using geographic information systems (GIS) were used to vizualize geospatial variation in soil and vine properties. Highly significant correlations (P < 0.01) emerged for pre-dawn leaf water potential (ΨPD), mid-day leaf water potential (ΨL) and PAW, with berry size, berry weight, pruning weights (canopy size) and soluble solids content (°Brix). Areas yielding grapes with perceived higher quality had vines with (1) lower leaf water potential (LWP) both pre-dawn and mid-day, (2) smaller berry diameter and weight, (3) lower pruning weights, and (4) higher °Brix. A trained sensory panel found grapes from the more water-stressed vines had significantly sweeter and softer pulp, absence of vegetal character, and browner and crunchier seeds. Metabolomic analysis of

FLUORIDE CONTENT OF COMMERCIALLY AVAILABLE BOTTLED DRINKING WATER IN BANGKOK, THAILAND.

PubMed

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.

The relationship between prevalence of active trachoma, water availability and its use in a Tanzanian village.

PubMed

Polack, Sarah; Kuper, Hannah; Solomon, Anthony W; Massae, Patrick A; Abuelo, Carolina; Cameron, Ewen; Valdmanis, Vivian; Mahande, Michael; Foster, Allen; Mabey, David

2006-11-01

This study aimed to establish the relationship between the prevalence of active trachoma in children, water availability and household water use in a village in Tanzania. Nine hundred and fourteen children aged 1-9 years were examined for signs of trachoma. Data were collected on time taken to collect water, amount of water collected and other trachoma risk factors. In a sub-study, 99 randomly selected households were visited twice daily on two consecutive days to document patterns of water use. The prevalence of active trachoma in the children examined was 18.4% (95% CI 15.9-20.9). Active trachoma prevalence increased with increasing water collection time (OR 2.25; 95% CI 1.13-4.46) but was unrelated to the amount of water collected. In the sub-study, active trachoma prevalence was substantially lower in children from households where more water was used for personal hygiene (P for trend < or =0.01), independent of the total amount of water used. The allocation of water to hygiene was predicted by lower water collection time. The key element in the relationship between water availability and trachoma is the allocation of water within households. Collection time may influence both the quantity of water collected and its allocation within the household.

Assessing the effects of adaptation measures on optimal water resources allocation under varied water availability conditions

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

Sector-wise midpoint characterization factors for impact assessment of regional consumptive and degradative water use.

PubMed

Lin, Chia-Chun; Lin, Jia-Yu; Lee, Mengshan; Chiueh, Pei-Te

2017-12-31

Water availability, resulting from either a lack of water or poor water quality is a key factor contributing to regional water stress. This study proposes a set of sector-wise characterization factors (CFs), namely consumptive and degradative water stresses, to assess the impact of water withdrawals with a life cycle assessment approach. These CFs consider water availability, water quality, and competition for water between domestic, agricultural and industrial sectors and ecosystem at the watershed level. CFs were applied to a case study of regional water management of industrial water withdrawals in Taiwan to show that both regional or seasonal decrease in water availability contributes to a high consumptive water stress, whereas water scarcity due to degraded water quality not meeting sector standards has little influence on increased degradative water stress. Degradative water stress was observed more in the agricultural sector than in the industrial sector, which implies that the agriculture sector may have water quality concerns. Reducing water intensity and alleviating regional scale water stresses of watersheds are suggested as approaches to decrease the impact of both consumptive and degradative water use. The results from this study may enable a more detailed sector-wise analysis of water stress and influence water resource management policies. Copyright © 2017 Elsevier B.V. All rights reserved.

WATER INFORMATION AVAILABLE FROM THE U. S. GEOLOGICAL SURVEY.

USGS Publications Warehouse

Showen, Charles R.

1985-01-01

As a part of the Geological Survey's program of releasing water data to the public, two large-scale computerized systems are maintained. The National Water Data Storage and Retrieval System was developed to provide more effective and efficient management of data-releasing activities and provides for the processing, storage, and retrieval of surface-water, ground-water and water-quality data. Another service available is providing assistance to users of water data to identify, locate, and acquire needed data. This service is provided by the National Water Data Exchange, which has the mission to identify sources of water data and to provide the connection between those who acquire and those who use water data.

Evaluating options for balancing the water-electricity nexus in California: part 1--securing water availability.

PubMed

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.

The Influence of Climate Change on Irrigated Water Demands and Surface Water Availability of the Yellow River Basin

NASA Astrophysics Data System (ADS)

Troy, T. J.; Zhang, J.

2017-12-01

Balancing irrigated water demands and surface water availability is critical for sustainable water resources management. In China, irrigation is the largest water user, and there is concern that irrigated water demands will be affected by climate change. If the relationship between climate change, irrigated water demands and surface water availability is quantified, then effective measures can be developed to maintain food production while ensuring water sustainability. This research focuses on the Yellow River, the second longest in China, and analyzes the impact of historical and projected climate change on agricultural water demands and surface water availability. Corn and wheat are selected as representative crops to estimate the effect of temperature and precipitin changes on irrigated water demands. The VIC model is used to simulate daily streamflow throughout the Yellow River, providing estimates of surface water availability. Overall, results indicate the irrigated water need and surface water availability are impacted by climate change, with spatially varying impacts depending on spatial patterns of climate trends and river network position. This research provides insight into water security in the Yellow River basin, indicating where water efficiency measures are needed and where they are not.

Potential Water Availability Index (PWAI): A New Water Vulnerability Index for Africa Based on GRACE Data

NASA Astrophysics Data System (ADS)

Hasan, E.; Tarhule, A.; Hong, Y.; Moore, B., III

2016-12-01

The critical role of water in enabling or constraining human wellbeing and socio-economic activities has led to interest in quantitatively establishing the status or index of water (in)sufficiency over time and space. Introduced in 1989, the first widely accepted index expressed the status of water resources availability in terms of vulnerability, stress, or scarcity. Since then, numerous refinements and modifications to the concept have been published but nearly all adopt the same basic formulation; water status is a function of available water resources and demand or use. However, accurately defining and assessing `available water' has proved problematic especially in data scarce regions, such as Africa. In this paper, we use Total Water Storage (TWS) estimated from NASA's Gravity Recovery and Climate Experiment (GRACE) in lieu of observational hydrologic data, to estimate the Water Scarcity Index (WSI) for Africa at country level. The monthly TWS Positive anomalies represent periods of net system recharge while negative anomalies represent net system loss due to evapotranspiration and anthropogenic withdrawals. The procedure is as follows. First, we calculated the long-term (2002-2014) Internal Water Storage (IWS) for each country using the monthly precipitation data from the Global Precipitation Climatology Centre (GPCC). Next, the yearly cumulative positive and negative anomalies were added to the long-term IWS to obtain volumetric Potential Water Storage (VPWS) per country. By dividing VPWS by population, we obtain estimates of per capita water availability which can be grouped into vulnerability classes using established thresholds. Our VPWS showed very high correlation (R2 =0.94, p=0.0001) with the values of Internal Renewable Water Resources (IRWR) estimated by AQUSTAT. Additionally, the GWSI is highly correlated (R2 =0.94, p=0.0001) with the existing WSI index from the world bank data center. The novelty and contribution of our approach is in using GRACE

Progress toward establishing a national assessment of water availability and use

USGS Publications Warehouse

Alley, William M.; Evenson, Eric J.; Barber, Nancy L.; Bruce, Breton W.; Dennehy, Kevin F.; Freeman, Mary C.; Freeman, Ward O.; Fischer, Jeffrey M.; Hughes, William B.; Kennen, Jonathan G.; Kiang, Julie E.; Maloney, Kelly O.; Musgrove, MaryLynn; Ralston, Barbara E.; Tessler, Steven; Verdin, James P.

2013-01-01

The Omnibus Public Land Management Act of 2009 (Public Law 111-11) was passed into law on March 30, 2009. Subtitle F, also known as the SECURE Water Act, calls for the establishment of a "national water availability and use assessment program" within the U.S. Geological Survey (USGS). A major driver for this recommendation was that national water availability and use have not been comprehensively assessed since 1978. This report fulfills a requirement to report to Congress on progress in implementing the national water availability and use assessment program, also referred to as the National Water Census. The SECURE Water Act authorized \\$20 million for each of fiscal years (FY) 2009 through 2023 for assessment of national water availability and use. The first appropriation for this effort was \\$4 million in FY 2011, followed by an appropriation of \\$6 million in FY 2012. The National Water Census synthesizes and reports information at the regional and national scales, with an emphasis on compiling and reporting the information in a way that is useful to states and others responsible for water management and natural-resource issues. The USGS works with Federal and non-Federal agencies, universities, and other organizations to ensure that the information can be aggregated with other types of water-availability and socioeconomic information, such as data on food and energy production. To maximize the utility of the information, the USGS coordinates the design and development of the effort through the Federal Advisory Committee on Water Information. A National Water Census is a complex undertaking, particularly because there are major gaps in the information needed to conduct such an assessment. To maximize progress, the USGS engaged stakeholders in a discussion of priorities and leveraged existing studies and program activities to enhance efforts toward the development of a National Water Census.

Influence of landscape heterogeneity on water available to tropical forests in an Amazonian catchment and implications for modeling drought response: Water Available to Tropical Forest

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

Fang, Yilin; Leung, L. Ruby; Duan, Zhuoran

The Amazon basin experienced periodic droughts in the past, and climate models projected more intense and frequent droughts in the future. How tropical forests respond to drought may depend on water availability, which is modulated by landscape heterogeneity. Using the one-dimensional ACME Land Model (ALM) and the three-dimensional ParFlow variably saturated flow model, a series of numerical experiments were performed for the Asu catchment in central Amazon to elucidate processes that influence water available for plant use and provide insights for improving Earth system models. Results from ParFlow show that topography has a dominant influence on groundwater table and runoffmore » through lateral flow. Without any representations of lateral processes, ALM simulates very different seasonal variations in groundwater table and runoff compared to ParFlow even if it is able to reproduce the long-term spatial average groundwater table of ParFlow through simple parameter calibration. In the ParFlow simulations, the groundwater table is evidently deeper and the soil saturation is lower in the plateau compared to the valley. However, even in the plateau during the dry season in the drought year of 2005, plant transpiration is not water stressed in the ParFlow simulations as the soil saturation is still sufficient to maintain a soil matric potential for the stomata to be fully open. This finding is insensitive to uncertainty in atmospheric forcing and soil parameters, but the empirical wilting formulation used in the models is an important factor that should be addressed using observations and modeling of coupled plant hydraulics-soil hydrology processes in future studies.« less

77 FR 15368 - Clean Water Act; Availability of List Decisions

Federal Register 2010, 2011, 2012, 2013, 2014

2012-03-15

... ENVIRONMENTAL PROTECTION AGENCY [FRL-9646-9] Clean Water Act; Availability of List Decisions...) proposed decision identifying water quality limited segments and associated pollutants in Oregon to be listed pursuant to section 303(d)(2) of the Clean Water Act (CWA). EPA is proposing to add 1004 water...

77 FR 54909 - Clean Water Act: Availability of List Decisions

Federal Register 2010, 2011, 2012, 2013, 2014

2012-09-06

... ENVIRONMENTAL PROTECTION AGENCY [FRL-9724-6] Clean Water Act: Availability of List Decisions... notice announces EPA's decision to identify certain water quality limited waters and the associated pollutant to be listed pursuant to the Clean Water Act Section 303(d)(2) on New York's list of impaired...

Reduction of Turbidity of Water Using Locally Available Natural Coagulants

PubMed Central

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

Multilayer geospatial analysis of water availability for shale resources development in Mexico

NASA Astrophysics Data System (ADS)

Galdeano, C.; Cook, M. A.; Webber, M. E.

2017-08-01

Mexico’s government enacted an energy reform in 2013 that aims to foster competitiveness and private investment throughout the energy sector value chain. As part of this reform, it is expected that extraction of oil and gas via hydraulic fracturing will increase in five shale basins (e.g. Burgos, Sabinas, Tampico, Tuxpan, and Veracruz). Because hydraulic fracturing is a water-intensive activity, it is relevant to assess the potential water availability for this activity in Mexico. This research aims to quantify the water availability for hydraulic fracturing in Mexico and identify its spatial distribution along the five shale basins. The methodology consisted of a multilayer geospatial analysis that overlays the water availability in the watersheds and aquifers with the different types of shale resources areas (e.g. oil and associated gas, wet gas and condensate, and dry gas) in the five shale basins. The aquifers and watersheds in Mexico are classified in four zones depending on average annual water availability. Three scenarios were examined based on different impact level on watersheds and aquifers from hydraulic fracturing. For the most conservative scenario analyzed, the results showed that the water available could be used to extract between 8.15 and 70.42 Quadrillion British thermal units (Quads) of energy in the typical 20-30 year lifetime of the hydraulic fracturing wells that could be supplied with the annual water availability overlaying the shale areas, with an average across estimates of around 18.05 Quads. However, geographic variation in water availability could represent a challenge for extracting the shale reserves. Most of the water available is located closer to the Gulf of Mexico, but the areas with the larger recoverable shale reserves coincide with less water availability in Northern Mexico. New water management techniques (such as recycling and re-use), more efficient fracturing methods, shifts in usage patterns, or other water sources need

Effects of soil water availability on water fluxes in winter wheat

NASA Astrophysics Data System (ADS)

Cai, G.; Vanderborght, J.; Langensiepen, M.; Vereecken, H.

2014-12-01

Quantifying soil water availability in water-limited ecosystems on plant water use continues to be a practical problem in agronomy. Transpiration which represents plant water demand is closely in relation to root water uptake in the root zone and sap flow in plant stems. However, few studies have been concentrated on influences of soil moisture on root water uptake and sap flow in crops. This study was undertaken to investigate (i) whether root water uptake and sap flow correlate with the transpiration estimated by the Penman-Monteith model for winter wheat(Triticum aestivum), and (ii) for which soil water potentials in the root zone, the root water uptake and sap flow rates in crop stems would be reduced. Therefore, we measured sap flow velocities by an improved heat-balance approach (Langensiepen et al., 2014), calculated crop transpiration by Penman-Monteith model, and simulated root water uptake by HYDRUS-1D on an hourly scale for different soil water status in winter wheat. In order to assess the effects of soil water potential on root water uptake and sap flow, an average soil water potential was calculated by weighting the soil water potential at a certain depth with the root length density. The temporal evolution of root length density was measured using horizontal rhizotubes that were installed at different depths.The results showed that root water uptake and sap flow matched well with the computed transpiration by Penman-Monteith model in winter wheat when the soil water potential was not limiting root water uptake. However, low soil water content restrained root water uptake, especially when soil water potential was lower than -90 kPa in the top soil. Sap flow in wheat was not affected by the observed soil water conditions, suggesting that stomatal conductance was not sensitive to soil water potentials. The effect of drought stress on root water uptake and sap flow in winter wheat was only investigated in a short time (after anthesis). Further research

Quantifying Fast and Slow Responses of Terrestrial Carbon Exchange across a Water Availability Gradient in North American Flux Sites

NASA Astrophysics Data System (ADS)

Biederman, J. A.; Scott, R. L.; Goulden, M.

2014-12-01

Climate change is predicted to increase the frequency and severity of water limitation, altering terrestrial ecosystems and their carbon exchange with the atmosphere. Here we compare site-level temporal sensitivity of annual carbon fluxes to interannual variations in water availability against cross-site spatial patterns over a network of 19 eddy covariance flux sites. This network represents one order of magnitude in mean annual productivity and includes western North American desert shrublands and grasslands, savannahs, woodlands, and forests with continuous records of 4 to 12 years. Our analysis reveals site-specific patterns not identifiable in prior syntheses that pooled sites. We interpret temporal variability as an indicator of ecosystem response to annual water availability due to fast-changing factors such as leaf stomatal response and microbial activity, while cross-site spatial patterns are used to infer ecosystem adjustment to climatic water availability through slow-changing factors such as plant community and organic carbon pools. Using variance decomposition, we directly quantify how terrestrial carbon balance depends on slow- and fast-changing components of gross ecosystem production (GEP) and total ecosystem respiration (TER). Slow factors explain the majority of variance in annual net ecosystem production (NEP) across the dataset, and their relative importance is greater at wetter, forest sites than desert ecosystems. Site-specific offsets from spatial patterns of GEP and TER explain one third of NEP variance, likely due to slow-changing factors not directly linked to water, such as disturbance. TER and GEP are correlated across sites as previously shown, but our site-level analysis reveals surprisingly consistent linear relationships between these fluxes in deserts and savannahs, indicating fast coupling of TER and GEP in more arid ecosystems. Based on the uncertainty associated with slow and fast factors, we suggest a framework for improved

Influence of free water availability on a desert carnivore and herbivore.

PubMed

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

PubMed Central

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

Simulations and field observations of root water uptake in plots with different soil water availability.

NASA Astrophysics Data System (ADS)

Cai, Gaochao; Vanderborght, Jan; Couvreur, Valentin; Javaux, Mathieu; Vereecken, Harry

2015-04-01

Root water uptake is a main process in the hydrological cycle and vital for water management in agronomy. In most models of root water uptake, the spatial and temporal soil water status and plant root distributions are required for water flow simulations. However, dynamic root growth and root distributions are not easy and time consuming to measure by normal approaches. Furthermore, root water uptake cannot be measured directly in the field. Therefore, it is necessary to incorporate monitoring data of soil water content and potential and root distributions within a modeling framework to explore the interaction between soil water availability and root water uptake. But, most models are lacking a physically based concept to describe water uptake from soil profiles with vertical variations in soil water availability. In this contribution, we present an experimental setup in which root development, soil water content and soil water potential are monitored non-invasively in two field plots with different soil texture and for three treatments with different soil water availability: natural rain, sheltered and irrigated treatment. Root development is monitored using 7-m long horizontally installed minirhizotubes at six depths with three replicates per treatment. The monitoring data are interpreted using a model that is a one-dimensional upscaled version of root water uptake model that describes flow in the coupled soil-root architecture considering water potential gradients in the system and hydraulic conductances of the soil and root system (Couvreur et al., 2012). This model approach links the total root water uptake to an effective soil water potential in the root zone. The local root water uptake is a function of the difference between the local soil water potential and effective root zone water potential so that compensatory uptake in heterogeneous soil water potential profiles is simulated. The root system conductance is derived from inverse modelling using

Availability of groundwater data for California, water year 2010

USGS Publications Warehouse

Ray, Mary; Orlando, Patricia v.P.

2011-01-01

The U.S. Geological Survey, in cooperation with Federal, State, and local agencies, obtains a large amount of data pertaining to the groundwater resources of California each water year (October 1-September 30). These data constitute a valuable database for developing an improved understanding of the water resources of the State. This Fact Sheet serves as an index to groundwater data for Water Year 2010. It contains a map of California showing the number of wells (by county) with available water-level or water-quality data for Water Year 2010 (fig. 1) and instructions for obtaining this and other groundwater information contained in the databases of the U.S. Geological Survey, California Water Science Center. From 1985 to 1993, data were published in the annual report "Water Resources Data for California, Volume 5. Ground-Water Data"; prior to 1985, the data were published in U.S. Geological Survey Water-Supply Papers.

Metropolitan Water Availability Forecasting Methods and Applications in South Florida

EPA Science Inventory

The availability of adequate fresh water is fundamental to the sustainable management of water infrastructures that support both urban needs and agricultural uses in human society. Recent drought events in the U.S. have threatened drinking water supplies for communities in Maryl...

Perception of drinking water safety and factors influencing acceptance and sustainability of a water quality intervention in rural southern India.

PubMed

Francis, Mark Rohit; Nagarajan, Guru; Sarkar, Rajiv; Mohan, Venkata Raghava; Kang, Gagandeep; Balraj, Vinohar

2015-07-30

Acceptance and long-term sustainability of water quality interventions are pivotal to realizing continued health benefits. However, there is limited research attempting to understand the factors that influence compliance to or adoption of such interventions. Eight focus group discussions with parents of young children--including compliant and not compliant households participating in an intervention study, and three key-informant interviews with village headmen were conducted between April and May 2014 to understand perceptions on the effects of unsafe water on health, household drinking water treatment practices, and the factors influencing acceptance and sustainability of an ongoing water quality intervention in a rural population of southern India. The ability to recognize health benefits from the intervention, ease of access to water distribution centers and the willingness to pay for intervention maintenance were factors facilitating acceptance and sustainability of the water quality intervention. On the other hand, faulty perceptions on water treatment, lack of knowledge about health hazards associated with drinking unsafe water, false sense of protection from locally available water, resistance to change in taste or odor of water and a lack of support from male members of the household were important factors impeding acceptance and long term use of the intervention. This study highlights the need to effectively involve communities at important stages of implementation for long term success of water quality interventions. Timely research on the factors influencing uptake of water quality interventions prior to implementation will ensure greater acceptance and sustainability of such interventions in low income settings.

78 FR 20912 - Clean Water Act: Availability of List Decisions

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-08

... ENVIRONMENTAL PROTECTION AGENCY [FRL-9798-8] Clean Water Act: Availability of List Decisions.... SUMMARY: The Clean Water Act requires that States periodically submit, and EPA approve or disapprove... are not stringent enough to attain or maintain State water quality standards and for which total...

The Water Availability Tool for Environmental Resources (WATER): A Water-Budget Modeling Approach for Managing Water-Supply Resources in Kentucky - Phase I: Data Processing, Model Development, and Application to Non-Karst Areas

USGS Publications Warehouse

Williamson, Tanja N.; Odom, Kenneth R.; Newson, Jeremy K.; Downs, Aimee C.; Nelson, Hugh L.; Cinotto, Peter J.; Ayers, Mark A.

2009-01-01

The Water Availability Tool for Environmental Resources (WATER) was developed in cooperation with the Kentucky Division of Water to provide a consistent and defensible method of estimating streamflow and water availability in ungaged basins. WATER is process oriented; it is based on the TOPMODEL code and incorporates historical water-use data together with physiographic data that quantitatively describe topography and soil-water storage. The result is a user-friendly decision tool that can estimate water availability in non-karst areas of Kentucky without additional data or processing. The model runs on a daily time step, and critical source data include a historical record of daily temperature and precipitation, digital elevation models (DEMs), the Soil Survey Geographic Database (SSURGO), and historical records of water discharges and withdrawals. The model was calibrated and statistically evaluated for 12 basins by comparing the estimated discharge to that observed at U.S. Geological Survey streamflow-gaging stations. When statistically evaluated over a 2,119-day time period, the discharge estimates showed a bias of -0.29 to 0.42, a root mean square error of 1.66 to 5.06, a correlation of 0.54 to 0.85, and a Nash-Sutcliffe Efficiency of 0.26 to 0.72. The parameter and input modifications that most significantly improved the accuracy and precision of streamflow-discharge estimates were the addition of Next Generation radar (NEXRAD) precipitation data, a rooting depth of 30 centimeters, and a TOPMODEL scaling parameter (m) derived directly from SSURGO data that was multiplied by an adjustment factor of 0.10. No site-specific optimization was used.

Water availability and subsidence in California's Central Valley

USGS Publications Warehouse

Faunt, Claudia C.; Sneed, Michelle

2015-01-01

California’s Central Valley covers about 52,000 square kilometers (km2) and is one of the most productive agricultural regions in the world. More than 250 different crops are grown in the broad alluvial filled structural trough, with an estimated value exceeding $20 billion per year (Faunt 2009) (Figure 1). Central Valley agriculture depends on state and federal water systems that divert surface water, predominantly originating from Sierra Nevada snowmelt, to agricultural fields. Because the valley is semi-arid and the availability of surface water varies substantially from year to year, season to season, and from north to south, agriculture, as it grew, developed a reliance on groundwater for irrigation.

Hindcast of water availability in regional aquifer systems using MODFLOW Farm Process

USGS Publications Warehouse

Schmid, Wolfgang; Hanson, Randall T.; Faunt, Claudia C.; Phillips, Steven P.

2015-01-01

Coupled groundwater and surface-water components of the hydrologic cycle can be simulated by the Farm Process for MODFLOW (MF-FMP) in both irrigated and non-irrigated areas and aquifer-storage and recovery systems. MF-FMP is being applied to three productive agricultural regions of different scale in the State of California, USA, to assess the availability of water and the impacts of alternative management decisions. Hindcast simulations are conducted for similar periods from the 1960s to near recent times. Historical groundwater pumpage is mostly unknown in one region (Central Valley) and is estimated by MF-FMP. In another region (Pajaro Valley), recorded pumpage is used to calibrate model-estimated pumpage. Multiple types of observations are used to estimate uncertain parameters, such as hydraulic, land-use, and farm properties. MF-FMP simulates how climate variability and water-import availability affect water demand and supply. MF-FMP can be used to predict water availability based on anticipated changes in anthropogenic or natural water demands. Keywords groundwater; surface-water; irrigation; water availability; response to climate variability/change

Assessing surface water availability considering human water use and projected climate variability

NASA Astrophysics Data System (ADS)

Ashraf, Batool; AghaKouchak, Amir; Mousavi-Baygi, Mohammd; Moftakhari, Hamed; Anjileli, Hassan

2017-04-01

Climate variability along with anthropogenic activities alter the hydrological cycle and local water availability. The overarching goal of this presentation is to demonstrate the compounding interactions between human water use/withdrawals and climate change and variability. We focus on Karkheh River basin and Urmia basin, in western Iran, that have high level of human activity and water use, and suffer from low water productivity. The future of these basins and their growth relies on sustainable water resources and hence, requires a holistic, basin-wide management to cope with water scarcity challenges. In this study, we investigate changes in the hydrology of the basin including human-induced alterations of the system, during the past three decades. Then, we investigate the individual and combined effects of climate variability and human water withdrawals on surface water storage in the 21st century. We use bias-corrected historical simulations and future projections from ensemble mean of eleven General Circulation Models (GCMs) under two climate change scenarios RCP4.5 and RCP8.5. The results show that, hydrology of the studied basins are significantly dominated by human activities over the baseline period (1976 - 2005). Results show that the increased anthropogenic water demand resulting from substantial socio-economic growth in the past three decades have put significant stress on water resources. We evaluate a number of future water demand scenarios and their interactions with future climate projections. Our results show that by the end of the 21st century, the compounding effects of increased irrigation water demand and precipitation variability may lead to severe local water scarcity in these basins. Our study highlights the necessity for understanding and considering the compounding effects of human water use and future climate projections. Such studies would be useful for improving water management and developing adaption plans in water scarce regions.

Water availability and land subsidence in the Central Valley, California, USA

NASA Astrophysics Data System (ADS)

Faunt, Claudia C.; Sneed, Michelle; Traum, Jon; Brandt, Justin T.

2016-05-01

The Central Valley in California (USA) covers about 52,000 km2 and is one of the most productive agricultural regions in the world. This agriculture relies heavily on surface-water diversions and groundwater pumpage to meet irrigation water demand. Because the valley is semi-arid and surface-water availability varies substantially, agriculture relies heavily on local groundwater. In the southern two thirds of the valley, the San Joaquin Valley, historic and recent groundwater pumpage has caused significant and extensive drawdowns, aquifer-system compaction and subsidence. During recent drought periods (2007-2009 and 2012-present), groundwater pumping has increased owing to a combination of decreased surface-water availability and land-use changes. Declining groundwater levels, approaching or surpassing historical low levels, have caused accelerated and renewed compaction and subsidence that likely is mostly permanent. The subsidence has caused operational, maintenance, and construction-design problems for water-delivery and flood-control canals in the San Joaquin Valley. Planning for the effects of continued subsidence in the area is important for water agencies. As land use, managed aquifer recharge, and surface-water availability continue to vary, long-term groundwater-level and subsidence monitoring and modelling are critical to understanding the dynamics of historical and continued groundwater use resulting in additional water-level and groundwater storage declines, and associated subsidence. Modeling tools such as the Central Valley Hydrologic Model, can be used in the evaluation of management strategies to mitigate adverse impacts due to subsidence while also optimizing water availability. This knowledge will be critical for successful implementation of recent legislation aimed toward sustainable groundwater use.

78 FR 45925 - Clean Water Act: Availability of List Decisions

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-30

... ENVIRONMENTAL PROTECTION AGENCY [FRL-9840-5] Clean Water Act: Availability of List Decisions... numeric water quality standards marine criterion for dissolved oxygen was not attained in these segments... 6's Web site at http://www.epa.gov/region6/water/npdes/tmdl/index.htm#303dlists , or by writing or...

Impacts of fresh and aged biochars on plant available water and water use efficiency

USDA-ARS?s Scientific Manuscript database

The ability of soils to hold sufficient plant available water (PAW) between rainfall events is critical to crop productivity. Most studies indicate that biochar amendments decrease soil bulk density and increase soil water retention. However, limited knowledge exists regarding biochars ability to in...

Assessment of water availability and demand in Lake Guiers , Senegal.

NASA Astrophysics Data System (ADS)

Sambou, D.; Weihrauch, D.; Hellwing, V.; Diekkrüger, B.; Höllermann, B.; Gaye, A. T.

2015-12-01

Assessment of water availability and demand in Lake Guiers, SenegalWater resources are critical to economic growth and social development. In most African countries, supply of drinking water to satisfy population needs is a key issue because of population growth and climate and land use change. During the last three decades, increasing population, changing patterns of water demand, and concentration of population and economic activities in urban areas has pressurize Senegal's freshwater resources. To overcome this deficit, Senegal turned, to the exploitation of the Lake Guiers. It is the sole water reservoir which can be used extensively as a stable freshwater. Its water is use for irrigating crops and sugar refinery and as a drinking water resource for urban centres, including Dakar, the capital city of Senegal, as well as for the local population and animal herds. To ensure sustainability, a greater understanding of Lake Guiers's water resources and effective management of its use will be required. In this study we developed and quantified future water situation (water availability and demand) in Lake Guiers under scenarios of climate change and population growth until 2050, using the water management model WEAP (Water Evaluation And Planning system). The results show that the pressure on Lake Guiers's water resources will increase, leading to greater competition between agriculture and municipal demand site. Decreasing inflows due to climate change will aggravate this situation. WEAP results offer basis to assister lake Guiers water resources manager for an efficient long-term planning and management. Keywords: climate change, population growth , IWRM, Lake Guiers, Senegal

Effects of trampling on morphological and mechanical traits of dryland shrub species do not depend on water availability.

PubMed

Xu, Liang; Freitas, Sofia M A; Yu, Fei-Hai; Dong, Ming; Anten, Niels P R; Werger, Marinus J A

2013-01-01

In semiarid drylands water shortage and trampling by large herbivores are two factors limiting plant growth and distribution. Trampling can strongly affect plant performance, but little is known about responses of morphological and mechanical traits of woody plants to trampling and their possible interaction with water availability. Seedlings of four shrubs (Caragana intermedia, Cynanchum komarovi, Hedysarum laeve and Hippophae rhamnoides) common in the semiarid Mu Us Sandland were grown at 4% and 10% soil water content and exposed to either simulated trampling or not. Growth, morphological and mechanical traits were measured. Trampling decreased vertical height and increased basal diameter and stem resistance to bending and rupture (as indicated by the increased minimum bend and break force) in all species. Increasing water availability increased biomass, stem length, basal diameter, leaf thickness and rigidity of stems in all species except C. komarovii. However, there were no interactive effects of trampling and water content on any of these traits among species except for minimum bend force and the ratio between stem resistance to rupture and bending. Overall shrub species have a high degree of trampling resistance by morphological and mechanical modifications, and the effects of trampling do not depend on water availability. However, the increasing water availability can also affect trade-off between stem strength and flexibility caused by trampling, which differs among species. Water plays an important role not only in growth but also in trampling adaptation in drylands.

Water availability and land subsidence in the Central Valley, California, USA

USGS Publications Warehouse

Faunt, Claudia; Sneed, Michelle; Traum, Jonathan A.; Brandt, Justin

2016-01-01

The Central Valley in California (USA) covers about 52,000 km2 and is one of the most productive agricultural regions in the world. This agriculture relies heavily on surface-water diversions and groundwater pumpage to meet irrigation water demand. Because the valley is semi-arid and surface-water availability varies substantially, agriculture relies heavily on local groundwater. In the southern two thirds of the valley, the San Joaquin Valley, historic and recent groundwater pumpage has caused significant and extensive drawdowns, aquifer-system compaction and subsidence. During recent drought periods (2007–2009 and 2012-present), groundwater pumping has increased owing to a combination of decreased surface-water availability and land-use changes. Declining groundwater levels, approaching or surpassing historical low levels, have caused accelerated and renewed compaction and subsidence that likely is mostly permanent. The subsidence has caused operational, maintenance, and construction-design problems for water-delivery and flood-control canals in the San Joaquin Valley. Planning for the effects of continued subsidence in the area is important for water agencies. As land use, managed aquifer recharge, and surface-water availability continue to vary, long-term groundwater-level and subsidence monitoring and modelling are critical to understanding the dynamics of historical and continued groundwater use resulting in additional water-level and groundwater storage declines, and associated subsidence. Modeling tools such as the Central Valley Hydrologic Model, can be used in the evaluation of management strategies to mitigate adverse impacts due to subsidence while also optimizing water availability. This knowledge will be critical for successful implementation of recent legislation aimed toward sustainable groundwater use.

Market factors and the availability of community pharmacies.

PubMed

Doucette, W R; Brooks, J M; Sorofman, B A; Wong, H

1999-07-01

The purpose of this study was to examine the relationships between the availability of community pharmacies and 4 types of market factors. A composite data set was created that linked, at the county level, data on: (1) type and number of pharmacies; (2) population characteristics; (3) payer variables; (4) health care system factors; and (5) competitive factors. In this exploratory study, secondary data were used to assess the association between the availability of community pharmacies and the influence of market factors. To assess the market influences on availability of community pharmacies, 2 regressions were performed. In 1 model, the number of community pharmacies per 10,000 population was the dependent variable, whereas the dependent variable in the other regression was the proportion of independently owned community pharmacies. The independent variables in each regression were the market factors--population characteristics, payer variables, health care system factors, and competitive variables. Squared terms were included for 8 of 15 market factors to account for nonlinearities in the relationships. Multiple market factors were correlated with both the number of community pharmacies and the proportion of independently owned pharmacies in an area. Several of the relationships were not linear and changed direction within the range of data. Counties with either a low or a high percentage of elderly people had fewer pharmacies and a lower proportion of independently owned pharmacies compared with counties with a moderate percentage of elderly people. Counties that were scarcely or highly rural had fewer community pharmacies but a higher proportion of independently owned pharmacies than counties that were moderately rural. Areas with a greater percentage of the population earning less than the poverty level had more pharmacies, especially independently owned ones. Fewer community pharmacies were found in areas with higher health maintenance organization

Factors affecting the availability of americium-241 to the rice plant

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

Adriano, D.C.

1979-11-01

Since there has been no published transuranic uptake data on the rice plant (Oryza sativa L.), greenhouse experiments were conducted to determine the effects of some factors on the uptake of /sup 241/Am by this crop. Results indicate that chelated /sup 241/Am (in the form of americium-241-diethylenetriaminepentaacetic acid) applied to the flood water was markedly taken up by the rice plant, compared to the nonchelated form. However, most of the accumulation of /sup 241/Am occurred in the vegetative parts and only trace amounts, if any, were translocated to the grain. Soil application of /sup 241/Am resulted in much lower uptake.more » Soil amendment with either diethylenetriaminepentaacetic acid (DTPA) or organic matter did not produce a discernible uptake pattern. A synthesis of published data on plant uptake of /sup 241/Am indicates that the concentration ratio (CR, a measure of availability of /sup 241/Am to the plants) values for /sup 241/Am for agricultural crops ranged from 10-/sup 6/ to 10/sup 1/ (from lowest to highest availability). Some factors that appear to influence /sup 241/Am uptake are as follows: plant parts (grain usually having lower CR), chelating agents (DTPA usually increasing the CR), organic matter (inconsistent effects although generally decreasing the CR), and lime (usually decreasing the CR).« less

Global Floods and Water Availability Driven by Atmospheric Rivers

NASA Astrophysics Data System (ADS)

Paltan, Homero; Waliser, Duane; Lim, Wee Ho; Guan, Bin; Yamazaki, Dai; Pant, Raghav; Dadson, Simon

2017-10-01

While emerging regional evidence shows that atmospheric rivers (ARs) can exert strong impacts on local water availability and flooding, their role in shaping global hydrological extremes has not yet been investigated. Here we quantify the relative contribution of ARs variability to both flood hazard and water availability. We find that globally, precipitation from ARs contributes 22% of total global runoff, with a number of regions reaching 50% or more. In areas where their influence is strongest, ARs may increase the occurrence of floods by 80%, while absence of ARs may increase the occurrence of hydrological droughts events by up to 90%. We also find that 300 million people are exposed to additional floods and droughts due the occurrence of ARs. ARs provide a source of hydroclimatic variability whose beneficial or damaging effects depend on the capacity of water resources managers to predict and adapt to them.

Global assessment of predictability of water availability: A bivariate probabilistic Budyko analysis

NASA Astrophysics Data System (ADS)

Wang, Weiguang; Fu, Jianyu

2018-02-01

Estimating continental water availability is of great importance for water resources management, in terms of maintaining ecosystem integrity and sustaining society development. To more accurately quantify the predictability of water availability, on the basis of univariate probabilistic Budyko framework, a bivariate probabilistic Budyko approach was developed using copula-based joint distribution model for considering the dependence between parameter ω of Wang-Tang's equation and the Normalized Difference Vegetation Index (NDVI), and was applied globally. The results indicate the predictive performance in global water availability is conditional on the climatic condition. In comparison with simple univariate distribution, the bivariate one produces the lower interquartile range under the same global dataset, especially in the regions with higher NDVI values, highlighting the importance of developing the joint distribution by taking into account the dependence structure of parameter ω and NDVI, which can provide more accurate probabilistic evaluation of water availability.

The hydraulic conductance of Fraxinus ornus leaves is constrained by soil water availability and coordinated with gas exchange rates.

PubMed

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.

Water availability and usage on the New Mexico/Mexico border.

PubMed

Li, Yongmei; Arnold, Stephen D; Kozel, Charles; Forster-Cox, Sue

2005-10-01

New Mexico, one of four states on the U.S./Mexico border, is faced with a pressing concern--lack of water. Since the region is either arid or semiarid, it is chronically short of continually available surface-water resources. Groundwater resources are used beyond their capacity to be recharged, and most surface-water resources are used to the maximum. The quality of groundwater varies widely. As a result of nonpoint- and point-source contamination, as well as natural occurrence, water in some areas is too salty or has high levels of natural uranium, fluoride, or arsenic. To date, the New Mexico Environment Department (NMED) has recognized 1,400 cases of groundwater contamination, and 1,907 water supply wells have been affected (NMED, 2001a). Of approximate 4,000 miles of coninously flowing rivers and streams in New Mexico, 92 perent are affected by nonpoint sources of pollution (NMED, 2001b). Numerous critical water issues exist along the New Mexico/Mexico border as a result of the impending critical issue of water availability, usage, and quality, as well as the fast-growing population. Related public health problems along the New Mexico/Mexico border are indicative of the need for a holistic, concrete, and sustainable solution to meet water demands in New Mexico. In order to accomplish the goals an objectives of Border XXI, Healthy People 2010, and Heathy Border 2010, a comprehensive statewide water management plan is needed. Solutions to the water demands of the region will be addressed in a subsequent manuscript.

Survival of Mycobacterium avium in drinking water biofilms as affected by water flow velocity, availability of phosphorus, and temperature.

PubMed

Torvinen, Eila; Lehtola, Markku J; Martikainen, Pertti J; Miettinen, Ilkka T

2007-10-01

Mycobacterium avium is a potential pathogen occurring in drinking water systems. It is a slowly growing bacterium producing a thick cell wall containing mycolic acids, and it is known to resist chlorine better than many other microbes. Several studies have shown that pathogenic bacteria survive better in biofilms than in water. By using Propella biofilm reactors, we studied how factors generally influencing the growth of biofilms (flow rate, phosphorus concentration, and temperature) influence the survival of M. avium in drinking water biofilms. The growth of biofilms was followed by culture and DAPI (4',6'-diamidino-2-phenylindole) staining, and concentrations of M. avium were determined by culture and fluorescence in situ hybridization methods. The spiked M. avium survived in biofilms for the 4-week study period without a dramatic decline in concentration. The addition of phosphorus (10 microg/liter) increased the number of heterotrophic bacteria in biofilms but decreased the culturability of M. avium. The reason for this result is probably that phosphorus increased competition with other microbes. An increase in flow velocity had no effect on the survival of M. avium, although it increased the growth of biofilms. A higher temperature (20 degrees C versus 7 degrees C) increased both the number of heterotrophic bacteria and the survival of M. avium in biofilms. In conclusion, the results show that in terms of affecting the survival of slowly growing M. avium in biofilms, temperature is a more important factor than the availability of nutrients like phosphorus.

Availability of water in Kalamazoo County, southwestern Michigan

USGS Publications Warehouse

Allen, William Burrows; Miller, John B.; Wood, Warren W.

1972-01-01

of the utmost importance. Levels at Crooked and Eagle Lakes have been maintained by pumping from lower aquifers. Diversion of water from Gourdneck Creek to West and Austin Lakes has helped in maintaining levels. Several relatively undeveloped lakes could be utilized as reservoirs whose storage could be used to augment streamflow or for water supply.Water in streams is generally of good chemical quality; however, several streams, including the Kalamazoo River downstream from Kalamazoo, have been degraded by municipal and industrial waste disposal. Water in the lakes is generally of good chemical quality with the exception of Barton Lake, which has been degraded by waste disposal. There is sufficient surface water available in Kalamazoo County to meet requirements for development of large quantities of water. The total available supply (average discharge of a stream) is about 680 mgd (million gallons per day). The dependable supply (7-day Q2, or average 7-day low flow having a recurrence interval of 2 years) is about 303 mgd. By developing artificial recharge facilities, surface runoff during winter and spring could be utilized to recharge ground-water reservoirs. Surface-water withdrawal in 1966 was about 58 mgd, of which 33 mgd was withdrawn from the Kalamazoo River. The quantity of water now being withdrawn from the ground and surface sources is small compared to the total that may be obtained in the area through full utilization of these resources. Mathematical models were used to simulate hydrologic conditions in the ground-water reservoirs and to evaluate maximum drawdowns for periods of little or no recharge. The practical limits of development as determined for the ground-water reservoirs are estimated to be at the following average withdrawal rates: Kalamazoo, 39 .mgd; Schoolcraft, 17 mgd; Kalamazoo-Portage, 24 mgd; and several small reservoirs, 67 mgd. These total 147 mgd. Further development would require additional artificial recharge facilities. Average

Olive response to water availability: yield response functions, soil water content indicators and evaluation of adaptability to climate change

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

Batch experiments versus soil pore water extraction--what makes the difference in isoproturon (bio-)availability?

PubMed

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.

Hydrologic models and analysis of water availability in Cuyama Valley, California

USGS Publications Warehouse

Hanson, R.T.; Flint, Lorraine E.; Faunt, Claudia C.; Gibbs, Dennis R.; Schmid, Wolfgang

2014-01-01

Changes in population, agricultural development practices (including shifts to more water-intensive crops), and climate variability are placing increasingly larger demands on available water resources, particularly groundwater, in the Cuyama Valley, one of the most productive agricultural regions in Santa Barbara County. The goal of this study was to produce a model capable of being accurate at scales relevant to water management decisions that could be considered in the evaluation of the sustainable water supply. The Cuyama Valley Hydrologic Model (CUVHM) was designed to simulate the most important natural and human components of the hydrologic system, including components dependent on variations in climate, thereby providing a reliable assessment of groundwater conditions and processes that can inform water users and help to improve planning for future conditions. Model development included a revision of the conceptual model of the flow system, construction of a precipitation-runoff model using the Basin Characterization Model (BCM), and construction of an integrated hydrologic flow model with MODFLOW-One-Water Hydrologic Flow Model (MF-OWHM). The hydrologic models were calibrated to historical conditions of water and land use and, then, used to assess the use and movement of water throughout the Valley. These tools provide a means to understand the evolution of water use in the Valley, its availability, and the limits of sustainability. The conceptual model identified inflows and outflows that include the movement and use of water in both natural and anthropogenic systems. The groundwater flow system is characterized by a layered geologic sedimentary sequence that—in combination with the effects of groundwater pumping, natural recharge, and the application of irrigation water at the land surface—displays vertical hydraulic-head gradients. Overall, most of the agricultural demand for water in the Cuyama Valley in the initial part of the growing season is

Arsenic in Drinking Water in Bangladesh: Factors Affecting Child Health

PubMed Central

Aziz, Sonia N.; Aziz, Khwaja M. S.; Boyle, Kevin J.

2014-01-01

The focus of this paper is to present an empirical model of factors affecting child health by observing actions households take to avoid exposure to arsenic in drinking water. Millions of Bangladeshis face multiple health hazards from high levels of arsenic in drinking water. Safe water sources are either expensive or difficult to access, affecting people’s individuals’ time available for work and ultimately affecting the health of household members. Since children are particularly susceptible and live with parents who are primary decision makers for sustenance, parental actions linking child health outcomes is used in the empirical model. Empirical results suggest that child health is significantly affected by the age and gender of the household water procurer. Adults with a high degree of concern for children’s health risk from arsenic contamination, and who actively mitigate their arsenic contaminated water have a positive effect on child health. PMID:24982854

Evaluation of Ground-Water Resources From Available Data, 1992, East Molokai Volcano, Hawaii

USGS Publications Warehouse

Anthony, Stephen S.

1995-01-01

Available ground-water data for East Molokai Volcano consist of well-construction information and records of ground-water pumpage, water levels, and chloride concentrations. Ground-water pumpage records are available for ten wells. Seventeen long-term (10 years or more) records of water-level and/or chloride concentration are available for eleven wells; however, only seven of these records are for observation wells. None of the available data show significant long-term changes in water level or chloride concentration; however, short-term changes due to variations in the quantity of water pumped, and rainfall are evident. Evaluation of the historical distribution and rates of ground-water pumpage, and variations in water levels and chloride concentrations is constrained by the scanty distribution of spatial and temporal data. Data show a range in water levels from greater than 850 feet above mean sea level in wells located in the windward valley of Waikolu to about 10 feet in wells located east of Kualapuu to 1 to 5 feet in the wells located along the south shore of East Molokai Volcano. An accurate contour map of water levels and chloride concentrations at the surface of the basal-water body cannot be constructed for any time period. Because water-level and chloride data are not collected at regular time intervals, many long-term records are incomplete. Information on the variation in chloride concentration with depth through the freshwater part of the basal-water body and into the zone of transition between freshwater and saltwater does not exist.

76 FR 20664 - Clean Water Act Section 303(d): Availability of List Decisions

Federal Register 2010, 2011, 2012, 2013, 2014

2011-04-13

... ENVIRONMENTAL PROTECTION AGENCY [FRL-9294-5] Clean Water Act Section 303(d): Availability of List... notice announces the availability of EPA's action identifying water quality limited segments and associated pollutants in Louisiana to be listed pursuant to Clean Water Act Section 303(d), and request for...

75 FR 52735 - Clean Water Act Section 303(d): Availability of List Decisions

Federal Register 2010, 2011, 2012, 2013, 2014

2010-08-27

... ENVIRONMENTAL PROTECTION AGENCY [FRL-9189-7] Clean Water Act Section 303(d): Availability of List...: This notice announces the availability of EPA's decision identifying 12 water quality limited waterbodies and associated pollutants in South Dakota to be listed pursuant to the Clean Water Act Section 303...

75 FR 68783 - Clean Water Act Section 303(d): Availability of List Decisions

Federal Register 2010, 2011, 2012, 2013, 2014

2010-11-09

... ENVIRONMENTAL PROTECTION AGENCY [FRL-9223-5] Clean Water Act Section 303(d): Availability of List Decisions AGENCY: Environmental Protection Agency (EPA). ACTION: Notice of availability. SUMMARY: This action announces the availability of EPA decisions identifying water quality limited segments and...

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.

Large Scale Evapotranspiration Estimates: An Important Component in Regional Water Balances to Assess Water Availability

NASA Astrophysics Data System (ADS)

Garatuza-Payan, J.; Yepez, E. A.; Watts, C.; Rodriguez, J. C.; Valdez-Torres, L. C.; Robles-Morua, A.

2013-05-01

used in a "kind of" crop factor manner for all vegetation types (including agricultural fields). Finally, the model uses air temperature and humidity, both extracted from the North American Land Data Assimilation System (NLDAS) database. ET estimates were then compared to ground truth data from four sites where long-term Eddy Covariance (EC) measurements of ET were conducted. This approach was developed and applied in Northern Mexico. Emphasis was placed on trying to minimize the large uncertainties that still remained on the temporal evolution and the spatial repartition of ET. Results show good agreement with ground data (with r2 greater than 0.7 on daily ET estimates) from the four sites evaluated using different vegetation types hence reducing the spatial uncertainties. Estimates of total annual ET were used in a water balance, assessing ground water availability for eleven aquifers in the state of Chihuahua. Annual ET in a four-year analysis period, ranged from 200 to 280 mm/year, representing 63 to 83 % of total annual precipitation, which reflects the importance of this component in the water balance. A GIS tool kit is under development to support decision makers at CONAGUA.

Hydrologic modeling for monitoring water availability in Eastern and Southern Africa

NASA Astrophysics Data System (ADS)

McNally, A.; Harrison, L.; Shukla, S.; Pricope, N. G.; Peters-Lidard, C. D.

2017-12-01

Severe droughts in 2015, 2016 and 2017 in Ethiopia, Southern Africa, and Somalia have negatively impacted agriculture and municipal water supplies resulting in food and water insecurity. Information from remotely sensed data and field reports indicated that the Famine Early Warning Systems Network (FEWS NET) Land Data Assimilation (FLDAS) accurately tracked both the anomalously low soil moisture, evapotranspiration and runoff conditions. This work presents efforts to more precisely monitor how the water balance responds to water availability deficits (i.e. drought) as estimated by the FLDAS with CHIRPS precipitation, MERRA-2 meteorological forcing and the Noah33 land surface model.Preliminary results indicate that FLDAS streamflow estimates are well correlated with observed streamflow where irrigation and other channel modifications are not present; FLDAS evapotranspiration (ET) is well correlated with ET from the Operational Simplified Surface Energy Balance model (SSEBop) in Eastern and Southern Africa. We then use these results to monitor availability, and explore trends in water supply and demand.

Fraser River watershed, Colorado : assessment of available water-quantity and water-quality data through water year 1997

USGS Publications Warehouse

Apodaca, Lori Estelle; Bails, Jeffrey B.

1999-01-01

The water-quantity and water-quality data for the Fraser River watershed through water year 1997 were compiled for ground-water and surface-water sites. In order to assess the water-quality data, the data were related to land use/land cover in the watershed. Data from 81 water-quantity and water-quality sites, which consisted of 9 ground-water sites and 72 surface-water sites, were available for analysis. However, the data were limited and frequently contained only one or two water-quality analyses per site.The Fraser River flows about 28 miles from its headwaters at the Continental Divide to the confluence with the Colorado River. Ground-water resources in the watershed are used for residential and municipal drinking-water supplies. Surface water is available for use, but water diversions in the upper parts of the watershed reduce the flow in the river. Land use/land cover in the watershed is predominantly forested land, but increasing urban development has the potential to affect the quantity and quality of the water resources.Analysis of the limited ground-water data in the watershed indicates that changes in the land use/land cover affect the shallow ground-water quality. Water-quality data from eight shallow monitoring wells in the alluvial aquifer show that iron and manganese concentrations exceeded the U.S. Environmental Protection Agency secondary maximum contaminant level. Radon concentrations from these monitoring wells exceeded the U.S. Environmental Protection Agency proposed maximum contaminant level. The proposed radon contaminant level is currently being revised. The presence of volatile organic compounds at two monitoring wells in the watershed indicates that land use affects the shallow ground water. In addition, bacteria detected in three samples are at concentrations that would be a concern for public health if the water was to be used as a drinking supply. Methylene blue active substances were detected in the ground water at some sites and are a

Perceptions about availability and adequacy of drinking water in a large California school district.

PubMed

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.

Factors affecting sustainability of rural water schemes in Swaziland

NASA Astrophysics Data System (ADS)

Peter, Graciana; Nkambule, Sizwe E.

The Millennium Development Goal (MDG) target to reduce the proportion of people without sustainable access to safe drinking water by the year 2015 has been met as of 2010, but huge disparities exist. Some regions, particularly Sub-Saharan Africa are lagging behind it is also in this region where up to 30% of the rural schemes are not functional at any given time. There is need for more studies on factors affecting sustainability and necessary measures which when implemented will improve the sustainability of rural water schemes. The main objective of this study was to assess the main factors affecting the sustainability of rural water schemes in Swaziland using a Multi-Criteria Analysis Approach. The main factors considered were: financial, social, technical, environmental and institutional. The study was done in Lubombo region. Fifteen functional water schemes in 11 communities were studied. Data was collected using questionnaires, checklist and focused group discussion guide. A total of 174 heads of households were interviewed. Statistical Package for Social Sciences (SPSS) was used to analyse the data and to calculate sustainability scores for water schemes. SPSS was also used to classify sustainability scores according to sustainability categories: sustainable, partially sustainable and non-sustainable. The averages of the ratings for the different sub-factors studied and the results on the sustainability scores for the sustainable, partially sustainable and non-sustainable schemes were then computed and compared to establish the main factors influencing sustainability of the water schemes. The results indicated technical and social factors as most critical while financial and institutional, although important, played a lesser role. Factors which contributed to the sustainability of water schemes were: functionality; design flow; water fetching time; ability to meet additional demand; use by population; equity; participation in decision making on operation and

Contribution potential of glaciers to water availability in different climate regimes

PubMed Central

Kaser, Georg; Großhauser, Martin; Marzeion, Ben

2010-01-01

Although reliable figures are often missing, considerable detrimental changes due to shrinking glaciers are universally expected for water availability in river systems under the influence of ongoing global climate change. We estimate the contribution potential of seasonally delayed glacier melt water to total water availability in large river systems. We find that the seasonally delayed glacier contribution is largest where rivers enter seasonally arid regions and negligible in the lowlands of river basins governed by monsoon climates. By comparing monthly glacier melt contributions with population densities in different altitude bands within each river basin, we demonstrate that strong human dependence on glacier melt is not collocated with highest population densities in most basins. PMID:21059938

On the New Concept of the Available Water Climatology and Its Application

NASA Astrophysics Data System (ADS)

Byun, H. R.; Kim, D. W.; Choi, K. S.; Deo, R. C.; Lee, S. M.; Park, C. K.; Kwon, S. H.; Kim, G. B.; Kwon, H. N.

2014-12-01

We propose a new concept of climatology called the Available Water Climate (AWC). Available water is 'the remained water usable in every moment' that is calculated regardless of any time intervals or the amounts of precipitation. With this concept, the Available Water Resources Index (AWRI) has been digitized following the earlier work of Byun and Lee (2002). The applicability of AWRI not only to the assessment and prediction of water related disasters but also to the academic researches has been tested. Resulted merits are as follows. Firstly, the threshold value of AWRI for the occurrence of all water related disasters like flood, drought, inundation landslide, and drought each region became clear, therefore the assessment and the prediction of them became much more precise than before. It became clear that the more extreme the AWRI value is, the severer the related disasters become. As example, all disasters caused by heavy rains, even though a small inundation, became predictable at the time step of heavy rain warning with the help of the Long-term remained water index(LWI). As another example, the drought intensity and its dates on start and end are defined with more reasonably and precisely than any other drought indexes with help of the Effective drought index (EDI) using sliding time scale. Secondly, the spatiotemporal distribution of water environment were digitized clearly and objectively using AWRI and new concepts of the Water Abundant Season (WAS) and the Little Water Season (LIWAS), their dates on start and end, and their strength were defined, which is very beneficial for agriculture, forestry, and all other water controls. Also, the differences of water environments among regions were clearly digitized and the improvement of the climate classification by Köppen etc. became possible. Thirdly, other merits will be found continuously afterwards.

Bacterial invasion potential in water is determined by nutrient availability and the indigenous community.

PubMed

Van Nevel, Sam; De Roy, Karen; Boon, Nico

2013-09-01

In drinking water (DW) and the distribution systems, bacterial growth and biofilm formation have to be controlled both for limiting taste or odour development and preventing clogging or biocorrosion problems. After a contamination with undesired bacteria, factors like nutrient availability and temperature will influence the survival of these invaders. Understanding the conditions enabling invaders to proliferate is essential for a holistic approach towards microbial risk assessment in DW. Pseudomonas putida was used as a model invader because this easy-growing bacterium can use a wide range of substrates. Invasion experiments in oligo- to eutrophic waters showed the requirement of both a carbon and phosphate source for survival of P. putida in DW. Addition of C, N and P enabled P. putida to grow in DW from 5.80 × 10(4) to 1.84 × 10(8) cells mL(-1) and survive for at least 12 days. However, in surface water with similar nutrient concentrations, P. putida did not survive, indicating the concomitant importance of the present indigenous microbial community of the specific water sample. Either extensive carbon or phosphate limitation can be used in water treatment design in order to obtain a DW which is not susceptible for unwanted bacterial growth. © 2013 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

Water availability drives gas exchange and growth of trees in northeastern US, not elevated CO2 and reduced acid deposition.

PubMed

Levesque, Mathieu; Andreu-Hayles, Laia; Pederson, Neil

2017-04-10

Dynamic global vegetation models (DGVM) exhibit high uncertainty about how climate change, elevated atmospheric CO 2 (atm. CO 2 ) concentration, and atmospheric pollutants will impact carbon sequestration in forested ecosystems. Although the individual roles of these environmental factors on tree growth are understood, analyses examining their simultaneous effects are lacking. We used tree-ring isotopic data and structural equation modeling to examine the concurrent and interacting effects of water availability, atm. CO 2 concentration, and SO 4 and nitrogen deposition on two broadleaf tree species in a temperate mesic forest in the northeastern US. Water availability was the strongest driver of gas exchange and tree growth. Wetter conditions since the 1980s have enhanced stomatal conductance, photosynthetic assimilation rates and, to a lesser extent, tree radial growth. Increased water availability seemingly overrides responses to reduced acid deposition, CO 2 fertilization, and nitrogen deposition. Our results indicate that water availability as a driver of ecosystem productivity in mesic temperate forests is not adequately represented in DGVMs, while CO 2 fertilization is likely overrepresented. This study emphasizes the importance to simultaneously consider interacting climatic and biogeochemical drivers when assessing forest responses to global environmental changes.

Temperature of water available for industrial use in the United States: Chapter F in Contributions to the hydrology of the United States, 1923-1924

USGS Publications Warehouse

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.

Compounding Impacts of Climate Change and Increased Human Water Withdrawal on Urmia Lake Water Availability

NASA Astrophysics Data System (ADS)

Alborzi, A.; Moftakhari, H.; Azaranfar, A.; Mallakpour, I.; Ashraf, B.; AghaKouchak, A.

2017-12-01

In recent decades, climate change and increase in human water withdrawal, combined, have caused ecological degradation in several terminal lakes worldwide. Among them, the shallow and hyper-saline Urmia Lake in Iran has experienced about 6 meters drawdown in lake level and 80% reduction in surface area. Here, we assess the imposed stress on Urmia Basin's water availability and Lake's ecological condition in response to coupled climate change and human-induced water withdrawal. A generalized river basin decision support system model consisting network flow is developed to simulate the basin-lake interactions under a wide range of scenarios. This model explicitly includes water management infrastructure, reservoirs, and irrigation and municipal water use. Studied scenarios represent a wide range of historic climate and water use scenarios including a historical baseline, future increase in water demand, and also improved water efficiency. In this presentation, we show the lake's water level, as a measure of lake's ecological health, under the compounding effects of the climate condition (top-down) and water use (bottom-up) scenarios. This method illustrates what combinations lead to failure in meeting the lake's ecological level.

Ground water security and drought in Africa: linking availability, access, and demand.

PubMed

Calow, Roger C; Macdonald, Alan M; Nicol, Alan L; Robins, Nick S

2010-01-01

Drought in Africa has been extensively researched, particularly from meteorological, agricultural, and food security perspectives. However, the impact of drought on water security, particularly ground water dependent rural water supplies, has received much less attention. Policy responses have concentrated on food needs, and it has often been difficult to mobilize resources for water interventions, despite evidence that access to safe water is a serious and interrelated concern. Studies carried out in Ghana, Malawi, South Africa, and Ethiopia highlight how rural livelihoods are affected by seasonal stress and longer-term drought. Declining access to food and water is a common and interrelated problem. Although ground water plays a vital role in buffering the effects of rainfall variability, water shortages and difficulties in accessing water that is available can affect domestic and productive water uses, with knock-on effects on food consumption and production. Total depletion of available ground water resources is rarely the main concern. A more common scenario is a spiral of water insecurity as shallow water sources fail, additional demands are put on remaining sources, and mechanical failures increase. These problems can be planned for within normal development programs. Water security mapping can help identify vulnerable areas, and changes to monitoring systems can ensure early detection of problems. Above all, increasing the coverage of ground water-based rural water supplies, and ensuring that the design and siting of water points is informed by an understanding of hydrogeological conditions and user demand, can significantly increase the resilience of rural communities to climate variability.

Identification of glacial melt water runoff in a karstic environment and its implication for present and future water availability

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.

Monitoring the Soil Water Availability of Young Urban Trees in Hamburg, Germany

NASA Astrophysics Data System (ADS)

Titel, Selina; Gröngröft, Alexander; Eschenbach, Annette

2017-04-01

In large cities numerous trees have to be planted each year to replace died off or cut down trees or for greening of constructed roads and newly built quarters. The typical age of planted trees is between five and fifteen years. Often the planting takes place in special planting pits to stimulate the tree growth under the restricted urban conditions. Consequently, trees are surrounded by different soil substrates: the soil from the nursery in the root ball, the special planting pit substrate and the surrounding urban soil which is often anthropogenic influenced. Being relocated in the city, trees have to cope with the warmer urban climate, the soil sealing and compaction and the low water storage capacity of the substrate. All factors together increase the probability of dry phases for roadside trees. The aim of this study is to monitor the soil water availability at sites of planted roadside trees during the first years after planting. Therefore, a measuring design was developed, which works automatically and takes the complex below ground structure of the soil into account. This approach consists of 13 soil water tension sensors inside and outside of each planting pit up to one meter depth connected to a data logger. The monitoring devices will finally be installed at 20 roadside trees (amongst others Quercus cerris, Quercus robur, Acer platanoides 'Fairview') in Hamburg, Germany, to identify phases of drought stress. The young trees were mainly planted in spring 2016. Data of the first year of measurements show, that the water tension varied between the different soil substrates and the depth. In the first year of tree growth in the city, soil in the tree root ball became significantly drier than the surrounding soil material. In late summer 2016 the water tension in the topsoil had the potential to cause drought stress below some trees.

Growth is required for perception of water availability to pattern root branches in plants.

PubMed

Robbins, Neil E; Dinneny, José R

2018-01-23

Water availability is a potent regulator of plant development and induces root branching through a process termed hydropatterning. Hydropatterning enables roots to position lateral branches toward regions of high water availability, such as wet soil or agar media, while preventing their emergence where water is less available, such as in air. The mechanism by which roots perceive the spatial distribution of water during hydropatterning is unknown. Using primary roots of Zea mays (maize) we reveal that developmental competence for hydropatterning is limited to the growth zone of the root tip. Past work has shown that growth generates gradients in water potential across an organ when asymmetries exist in the distribution of available water. Using mathematical modeling, we predict that substantial growth-sustained water potential gradients are also generated in the hydropatterning competent zone and that such biophysical cues inform the patterning of lateral roots. Using diverse chemical and environmental treatments we experimentally demonstrate that growth is necessary for normal hydropatterning of lateral roots. Transcriptomic characterization of the local response of tissues to a moist surface or air revealed extensive regulation of signaling and physiological pathways, some of which we show are growth-dependent. Our work supports a "sense-by-growth" mechanism governing hydropatterning, by which water availability cues are rendered interpretable through growth-sustained water movement. Copyright © 2018 the Author(s). Published by PNAS.

Growth is required for perception of water availability to pattern root branches in plants

PubMed Central

2018-01-01

Water availability is a potent regulator of plant development and induces root branching through a process termed hydropatterning. Hydropatterning enables roots to position lateral branches toward regions of high water availability, such as wet soil or agar media, while preventing their emergence where water is less available, such as in air. The mechanism by which roots perceive the spatial distribution of water during hydropatterning is unknown. Using primary roots of Zea mays (maize) we reveal that developmental competence for hydropatterning is limited to the growth zone of the root tip. Past work has shown that growth generates gradients in water potential across an organ when asymmetries exist in the distribution of available water. Using mathematical modeling, we predict that substantial growth-sustained water potential gradients are also generated in the hydropatterning competent zone and that such biophysical cues inform the patterning of lateral roots. Using diverse chemical and environmental treatments we experimentally demonstrate that growth is necessary for normal hydropatterning of lateral roots. Transcriptomic characterization of the local response of tissues to a moist surface or air revealed extensive regulation of signaling and physiological pathways, some of which we show are growth-dependent. Our work supports a “sense-by-growth” mechanism governing hydropatterning, by which water availability cues are rendered interpretable through growth-sustained water movement. PMID:29317538

Water availability change in central Belgium for the late 21st century

NASA Astrophysics Data System (ADS)

Tabari, Hossein; Taye, Meron Teferi; Willems, Patrick

2015-08-01

We investigate the potential impact of climate change on water availability in central Belgium. Two water balance components being precipitation and potential evapotranspiration are initially projected for the late 21st century (2071-2100) based on 30 Coupled Models Intercomparison Project phase 5 (CMIP5) models relative to a baseline period of 1961-1990, assuming forcing by four representative concentration pathway emission scenarios (RCP2.6, RCP4.5, RCP6.0, RCP8.5). The future available water is then estimated as the difference between precipitation and potential evapotranspiration projections. The number of wet days and mean monthly precipitation for summer season is projected to decrease in most of the scenarios, while the projections show an increase in those variables for the winter months. Potential evapotranspiration is expected to increase during both winter and summer seasons. The results show a decrease in water availability for summer and an increase for winter, suggesting drier summers and wetter winters for the late 21st century in central Belgium.

Factors influencing sustainability of communally-managed water facilities in rural areas of Zimbabwe

NASA Astrophysics Data System (ADS)

Kativhu, T.; Mazvimavi, D.; Tevera, D.; Nhapi, I.

2017-08-01

Sustainability of point water facilities is a major development challenge in many rural settings of developing countries not sparing those in the Sub-Saharan Africa region. This study was done in Zimbabwe to investigate the factors influencing sustainability of rural water supply systems. A total of 399 water points were studied in Nyanga, Chivi and Gwanda districts. Data was collected using a questionnaire, observation checklist and key informant interview guide. Multi-Criteria analysis was used to assess the sustainability of water points and inferential statistical analysis such as Chi square tests and Analysis of Variance (ANOVA) were used to determine if there were significant differences on selected variables across districts and types of lifting devices used in the study area. The thematic approach was used to analyze qualitative data. Results show that most water points were not functional and only 17% across the districts were found to be sustainable. A fusion of social, technical, financial, environmental and institutional factors was found to be influencing sustainability. On technical factors the ANOVA results show that the type of lifting device fitted at a water point significantly influences sustainability (F = 37.4, p < 0.01). Availability of spare parts at community level was found to be determining the downtime period of different lifting devices in the studied wards. Absence of user committees was found to be central in influencing sustainability as water points that did not have user committees were not sustainable and most of them were not functional during the time of the survey. Active participation by communities at the planning stage of water projects was also found to be critical for sustainability although field results showed passive participation by communities at this critical project stage. Financial factors of adequacy of financial contributions and establishment of operation and maintenance funds were also found to be of great

Global monthly water scarcity: blue water footprints versus blue water availability.

PubMed

Hoekstra, Arjen Y; Mekonnen, Mesfin M; Chapagain, Ashok K; Mathews, Ruth E; Richter, Brian D

2012-01-01

Freshwater scarcity is a growing concern, placing considerable importance on the accuracy of indicators used to characterize and map water scarcity worldwide. We improve upon past efforts by using estimates of blue water footprints (consumptive use of ground- and surface water flows) rather than water withdrawals, accounting for the flows needed to sustain critical ecological functions and by considering monthly rather than annual values. We analyzed 405 river basins for the period 1996-2005. In 201 basins with 2.67 billion inhabitants there was severe water scarcity during at least one month of the year. The ecological and economic consequences of increasing degrees of water scarcity--as evidenced by the Rio Grande (Rio Bravo), Indus, and Murray-Darling River Basins--can include complete desiccation during dry seasons, decimation of aquatic biodiversity, and substantial economic disruption.

Using the CAUSE Model to Understand Public Communication about Water Risks: Perspectives from Texas Groundwater District Officials on Drought and Availability.

PubMed

VanDyke, Matthew S; King, Andy J

2017-12-05

Public communication about drought and water availability risks poses challenges to a potentially disinterested public. Water management professionals, though, have a responsibility to work with the public to engage in communication about water and environmental risks. Because limited research in water management examines organizational communication practices and perceptions, insights into research and practice can be gained through investigation of current applications of these risk communication efforts. Guided by the CAUSE model, which explains common goals in communicating risk information to the public (e.g., creating Confidence, generating Awareness, enhancing Understanding, gaining Satisfaction, and motivating Enactment), semistructured interviews of professionals (N = 25) employed by Texas groundwater conservation districts were conducted. The interviews examined how CAUSE model considerations factor in to communication about drought and water availability risks. These data suggest that many work to build constituents' confidence in their districts. Although audiences and constituents living in drought-prone areas were reported as being engaged with water availability risks and solutions, many district officials noted constituents' lack of perceived risk and engagement. Some managers also indicated that public understanding was a secondary concern of their primary responsibilities and that the public often seemed apathetic about technical details related to water conservation risks. Overall, results suggest complicated dynamics between officials and the public regarding information access and motivation. The article also outlines extensions of the CAUSE model and implications for improving public communication about drought and water availability risks. © 2017 Society for Risk Analysis.

Global Change And Water Availability And Quality: Challenges Ahead

NASA Astrophysics Data System (ADS)

Larsen, M. C.; Ryker, S. J.

2012-12-01

The United States is in the midst of a continental-scale, multi-year water-resources experiment, in which society has not defined testable hypotheses or set the duration and scope of the experiment. What are we doing? We are expanding population at two to three times the national growth rate in our most water-scarce states, in the southwest, where water stress is already great and modeling predicts decreased streamflow by the middle of this century. We are expanding irrigated agriculture from the west into the east, particularly to the southeastern states, where increased competition for ground and surface water has urban, agricultural, and environmental interests at odds, and increasingly, in court. We are expanding our consumption of pharmaceutical and personal care products to historic high levels and disposing of them in surface and groundwater, through sewage treatment plants and individual septic systems that were not designed to treat them. These and other examples of our national-scale experiment are likely to continue well into the 21st century. This experiment and related challenges will continue and likely intensify as non-climatic and climatic factors, such as predicted rising temperature and changes in the distribution of precipitation in time and space, continue to develop.

Availability of drinking water in US public school cafeterias.

PubMed

Hood, Nancy E; Turner, Lindsey; Colabianchi, Natalie; Chaloupka, Frank J; Johnston, Lloyd D

2014-09-01

This study examined the availability of free drinking water during lunchtime in US public schools, as required by federal legislation beginning in the 2011-2012 school year. Data were collected by mail-back surveys in nationally representative samples of US public elementary, middle, and high schools from 2009-2010 to 2011-2012. Overall, 86.4%, 87.4%, and 89.4% of students attended elementary, middle, and high schools, respectively, that met the drinking water requirement. Most students attended schools with existing cafeteria drinking fountains and about one fourth attended schools with water dispensers. In middle and high schools, respondents were asked to indicate whether drinking fountains were clean, and whether they were aware of any water-quality problems at the school. The vast majority of middle and high school students (92.6% and 90.4%, respectively) attended schools where the respondent perceived drinking fountains to be clean or very clean. Approximately one in four middle and high school students attended a school where the survey respondent indicated that there were water-quality issues affecting drinking fountains. Although most schools have implemented the requirement to provide free drinking water at lunchtime, additional work is needed to promote implementation at all schools. School nutrition staff at the district and school levels can play an important role in ensuring that schools implement the drinking water requirement, as well as promote education and behavior-change strategies to increase student consumption of water at school. Copyright © 2014 Academy of Nutrition and Dietetics. Published by Elsevier Inc. All rights reserved.

Global Monthly Water Scarcity: Blue Water Footprints versus Blue Water Availability

PubMed Central

Hoekstra, Arjen Y.; Mekonnen, Mesfin M.; Chapagain, Ashok K.; Mathews, Ruth E.; Richter, Brian D.

2012-01-01

Freshwater scarcity is a growing concern, placing considerable importance on the accuracy of indicators used to characterize and map water scarcity worldwide. We improve upon past efforts by using estimates of blue water footprints (consumptive use of ground- and surface water flows) rather than water withdrawals, accounting for the flows needed to sustain critical ecological functions and by considering monthly rather than annual values. We analyzed 405 river basins for the period 1996–2005. In 201 basins with 2.67 billion inhabitants there was severe water scarcity during at least one month of the year. The ecological and economic consequences of increasing degrees of water scarcity – as evidenced by the Rio Grande (Rio Bravo), Indus, and Murray-Darling River Basins – can include complete desiccation during dry seasons, decimation of aquatic biodiversity, and substantial economic disruption. PMID:22393438

High sensitivity of northeastern broadleaf forest trees to water availability

NASA Astrophysics Data System (ADS)

Levesque, M.; Pederson, N.; Andreu-Hayles, L.

2015-12-01

Temperate deciduous forests of eastern US provide goods and services to millions of people and play a vital role in the terrestrial carbon and hydrological cycles. However, ongoing climate change and increased in CO2 concentration in the atmosphere (ca) are expected to alter growth and gas exchange of trees, and ultimately forest productivity. Still, the magnitude of these effects is unclear. A better comprehension of the species-specific responses to environmental changes will better inform models and managers on the vulnerability and resiliency of these forests. Tree-ring analysis was combined with δ¹³C and δ18O measurements to investigate growth and physiological responses of red oak (Quercus rubra L.) and tulip poplar (Liriodendron tulipifera L.) in northeastern US to changes in water availability and ca for the period 1950-2014. We found very strong correlations between summer climatic water balance (June-August) and isotopic tree-ring series for δ¹³C (r = -0.65 and -0.73), and δ18O (r = -0.59 and -0.70), for red oak and tulip poplar, respectively. In contrast, tree-ring width was less sensitive to summer water availability (r = 0.33-0.39). Prior to the mid 1980s, low water availability resulted in low stomatal conductance, photosynthesis, and growth. Since that period, pluvial conditions occurring in northeastern US have increased stomatal conductance, carbon uptake, and growth of both species. These findings demonstrate that broadleaf trees in this region could be more sensitive to drought than expected. This appears especially true since much of the calibration period looks wet in a multi-centennial perspective. Further, stronger spatial correlations were found between climate data with tree-ring isotopes than with tree-ring width and the geographical area of the observed δ18O-precipitation response (i.e. the area over which correlations are > 0.5) covers most of the northeastern US. Given the good fit between the isotopic time series and water

Water availability limits tolerance of apical damage in the Chilean tarweed Madia sativa

NASA Astrophysics Data System (ADS)

Gonzáles, Wilfredo L.; Suárez, Lorena H.; Molina-Montenegro, Marco A.; Gianoli, Ernesto

2008-07-01

Plant tolerance is the ability to reduce the negative impact of herbivory on plant fitness. Numerous studies have shown that plant tolerance is affected by nutrient availability, but the effect of soil moisture has received less attention. We evaluated tolerance of apical damage (clipping that mimicked insect damage) under two watering regimes (control watering and drought) in the tarweed Madia sativa (Asteraceae). We recorded number of heads with seeds and total number of heads as traits related to fitness. Net photosynthetic rate, water use efficiency, number of branches, shoot biomass, and the root:shoot biomass ratio were measured as traits potentially related to tolerance via compensatory responses to damage. In the drought treatment, damaged plants showed ≈43% reduction in reproductive fitness components in comparison with undamaged plants. In contrast, there was no significant difference in reproductive fitness between undamaged and damaged plants in the control watering treatment. Shoot biomass was not affected by apical damage. The number of branches increased after damage in both water treatments but this increase was limited by drought stress. Net photosynthetic rate increased in damaged plants only in the control watering treatment. Water use efficiency increased with drought stress and, in plants regularly watered, also increased after damage. Root:shoot ratio was higher in the low water treatment and damaged plants tended to reduce root:shoot ratio only in this water treatment. It is concluded that water availability limits tolerance to apical damage in M. sativa, and that putative compensatory mechanisms are differentially affected by water availability.

Caries prevalence and its association with brushing habits, water availability, and the intake of sugared beverages.

PubMed

Guido, Joseph A; Martinez Mier, Esperanza A; Soto, Armando; Eggertsson, Hafsteinn; Sanders, Brian J; Jones, James E; Weddell, James A; Villanueva Cruz, Irma; Anton de la Concha, Jose Luis

2011-11-01

BACKGROUND. With Dental Caries being the most common disease amongst children in the world today, there is a need to fully understand risk factors that may be related to caries prevalence and how they could be best addressed. AIM. The aim of this study was to evaluate soda, juice, sugared-beverage intake, brushing habits, and community water source availability as they relate to the prevalence of both noncavitated and cavitated caries lesions in small rural villages in Mexico. DESIGN. The International Caries Detection and Assessment System (ICDAS) was used in children from small, isolated, villages in Mexico. Risk factors were assessed via questionnaires. RESULTS. Caries prevalence in the villages was very high, ranging from 94.7% to 100% of the children studied. The mean number of surfaces with lesions per child (D1MFS + d1mfs) having scores ≥1 (noncavitated and cavitated) ranged from 15.4 ± 11.1 to 26.6 ± 15.2. Many of the children reported drinking beverages containing sugar. CONCLUSIONS. Drinking sugared beverages, poor oral hygiene habits, and lack of access to tap water were identified as risk factor for caries in this sample of residents of rural Mexico. © 2011 The Authors. International Journal of Paediatric Dentistry © 2011 BSPD, IAPD and Blackwell Publishing Ltd.

Impact of Unconventional Energy Development using Hydraulic Fracturing on Louisiana Water Resources Availability.

NASA Astrophysics Data System (ADS)

Unruh, H. G., Sr.; Habib, E. H.; Borrok, D. M.

2017-12-01

Unconventional oil and gas extraction around United States has been deployed significantly in the recent years. The current study focuses on the impact of Hydraulic fracturing (HF) on the sustainability of water resources in Louisiana. This impact is measured by quantifying the stress for current and future scenarios of HF water use in the two-main shale plays in Louisiana, the Haynesville and Tuscaloosa. The assessment is conducted at the HUC-12 fine catchment spatial scale. Initially, sectored stress metrics were calculated for surface and groundwater, respectively, without including HF water use. Demand sectors involved in this first stress estimation are power generation, public supply, industrial, etc. Once both stress metrics were estimated with the reported water sources and uses in Louisiana corresponding to the 2010 year, several scenarios for both sources were evaluated. In the first scenario, a peak year (2011) of HF water use was added as a water demand new category into the stress calculation matrices. The results indicate that a significant variability in the calculated stress metric with and without HF is reflected only for the groundwater sector. On the other hand, surface water sector doesn't seem to be affected for the HF water use. However, this apparent abundant surface water in the catchment, the location of the wells is not always adjacent to the body of water, and then trucking or piping of water may be required. For this reason, availability of groundwater in situ is a relevant factor in terms of production cost. Additional tested scenarios consist of increasing the number of wells in both shale play locations. Existing wells scenario calculates the stress including the water use of the total number of wells that currently exist in both shale plays in a short period (one year). The other additional tested scenario consists of increase of 100% of the required number of wells to extract the expected total shale play capacity. Results of the

Estimating plant available water for general crop simulations in ALMANAC/APEX/EPIC/SWAT

USDA-ARS?s Scientific Manuscript database

Process-based simulation models ALMANAC/APEX/EPIC/SWAT contain generalized plant growth subroutines to predict biomass and crop yield. Environmental constraints typically restrict plant growth and yield. Water stress is often an important limiting factor; it is calculated as the sum of water use f...

Water availability predicts forest canopy height at the global scale.

PubMed

Klein, Tamir; Randin, Christophe; Körner, Christian

2015-12-01

The tendency of trees to grow taller with increasing water availability is common knowledge. Yet a robust, universal relationship between the spatial distribution of water availability and forest canopy height (H) is lacking. Here, we created a global water availability map by calculating an annual budget as the difference between precipitation (P) and potential evapotranspiration (PET) at a 1-km spatial resolution, and in turn correlated it with a global H map of the same resolution. Across forested areas over the globe, Hmean increased with P-PET, roughly: Hmean (m) = 19.3 + 0.077*(P-PET). Maximum forest canopy height also increased gradually from ~ 5 to ~ 50 m, saturating at ~ 45 m for P-PET > 500 mm. Forests were far from their maximum height potential in cold, boreal regions and in disturbed areas. The strong association between forest height and P-PET provides a useful tool when studying future forest dynamics under climate change, and in quantifying anthropogenic forest disturbance. © 2015 John Wiley & Sons Ltd/CNRS.

Mediterranean shrub vegetation: soil protection vs. water availability

NASA Astrophysics Data System (ADS)

García Estringana, Pablo; Nieves Alonso-Blázquez, M.; Alegre, Alegre; Cerdà, Artemi

2014-05-01

Soil Erosion and Land Degradation are closely related to the changes in the vegetation cover (Zhao et al., 2013). Although other factors such as rainfall intensiy or slope (Ziadat and Taimeh, 2013) the plant covers is the main factor that controls the soil erosion (Haregeweyn, 2013). Plant cover is the main factor of soil erosion processes as the vegetation control the infiltration and runoff generation (Cerdà, 1998a; Kargar Chigani et al., 2012). Vegetation cover acts in a complex way in influencing on the one hand on runoff and soil loss and on the other hand on the amount and the way that rainfall reaches the soil surface. In arid and semiarid regions, where erosion is one of the main degradation processes and water is a scant resource, a minimum percentage of vegetation coverage is necessary to protect the soil from erosion, but without compromising the availability of water (Belmonte Serrato and Romero Diaz, 1998). This is mainly controlled by the vegetation distribution (Cerdà, 1997a; Cammeraat et al., 2010; Kakembo et al., 2012). Land abandonment is common in Mediterranean region under extensive land use (Cerdà, 1997b; García-Ruiz, 2010). Abandoned lands typically have a rolling landscape with steep slopes, and are dominated by herbaceous communities that grow on pasture land interspersed by shrubs. Land abandonment use to trigger an increase in soil erosion, but the vegetation recovery reduces the impact of the vegetation. The goal of this work is to assess the effects of different Mediterranean shrub species (Dorycnium pentaphyllum Scop., Medicago strasseri, Colutea arborescens L., Retama sphaerocarpa, L., Pistacia Lentiscus L. and Quercus coccifera L.) on soil protection (runoff and soil losses) and on rainfall reaching soil surface (rainfall partitioning fluxes). To characterize the effects of shrub vegetation and to evaluate their effects on soil protection, two field experiments were carried out. The presence of shrub vegetation reduced runoff by

Assessment of water availability and its relationship with vegetation distribution over a tropical montane system

NASA Astrophysics Data System (ADS)

Streher, A. S.; Sobreiro, J. F. F.; Silva, T. S. F.

2017-12-01

these ecosystems by possible alterations on the hydrological cycle and, consequently, capacity for adaptations on water use. These could lead to shifts in vegetation composition and distribution within the studied region. Further investigation of seasonal trends on water availability and edaphic factors would improve these analyses.

Stover removal effects on seasonal soil water availability under full and deficit irrigation

USDA-ARS?s Scientific Manuscript database

Removing corn (Zea mays L.) stover for livestock feed or bioenergy feedstock may impact water availability in the soil profile to support crop growth. The role of stover in affecting soil profile water availability will depend on annual rainfall inputs as well as irrigation level. To assess how res...

75 FR 71431 - Clean Water Act Section 303(d): Availability of List Decisions Correction

Federal Register 2010, 2011, 2012, 2013, 2014

2010-11-23

... ENVIRONMENTAL PROTECTION AGENCY [FRL-9230-1] Clean Water Act Section 303(d): Availability of List... Availability. SUMMARY: This action corrects a Federal Register notice that published on November 9, 2010 at 75 FR 68783 announcing the availability of EPA decisions identifying water quality limited segments and...

Viability of commercially available bleach for water treatment in developing countries.

PubMed

Lantagne, Daniele S

2009-11-01

Treating household water with low-cost, widely available commercial bleach is recommended by some organizations to improve water quality and reduce disease in developing countries. I analyzed the chlorine concentration of 32 bleaches from 12 developing countries; the average error between advertised and measured concentration was 35% (range = -45%-100%; standard deviation = 40%). Because of disparities between advertised and actual concentration, the use of commercial bleach for water treatment in developing countries is not recommended without ongoing quality control testing.

The Coupling of Ecosystem Productivity and Water Availability in Dryland Regions

NASA Astrophysics Data System (ADS)

Scott, R. L.; Biederman, J. A.; Barron-Gafford, G.

2014-12-01

Land cover and climatic change will alter biosphere-atmosphere exchanges of water vapor and carbon dioxide depending, in part, on feedbacks between biotic activity and water availability. Eddy covariance observations allow us to estimate ecosystem-scale productivity and respiration, and these datasets are now becoming sufficiently mature to advance understanding of these ecohydrological interactions. Here we use a network of sites in semiarid western North America representing gradients of water availability and functional plant type. We examine how precipitation (P) controls evapotranspiration (ET), net ecosystem production (NEP), and its component fluxes of ecosystem respiration (Reco) and gross ecosystem production (GEP). Despite the high variability in seasonal and annual precipitation timing and amounts that we expect to influence ecosystem function, we find persistent overall relationships between P or ET and the fluxes of NEP, Reco and GEP across the network, indicating a commonality and resilience in ecosystem soil and plant response to water availability. But we also observe several important site differences such as prior seasonal legacy effects on subsequent fluxes which vary depending on dominant plant functional type. For example, multiyear droughts, episodic cool-season droughts, and hard winter freezes seem to affect the herbaceous species differently than the woody ones. Nevertheless, the overall, strong coupling between hydrologic and ecologic processes at these sites bolsters our ability to predict the response of dryland ecosystems to future precipitation change.

Middle-term metropolitan water availability index assessment based on synergistic potentials of multi-sensor data

NASA Astrophysics Data System (ADS)

Chang, Ni-Bin; Yang, Y. Jeffrey; Daranpob, Ammarin

2010-03-01

The impact of recent drought and water pollution episodes results in an acute need to project future water availability to assist water managers in water utility infrastructure management within many metropolitan regions. Separate drought and water quality indices previously developed might not be sufficient for the purpose of such an assessment. This paper describes the development of the "Metropolitan Water Availability Index (MWAI)" and its potential applications in assessing the middle-term water availability at the watershed scale in a fast growing metropolitan region - the Manatee County near Tampa Bay, Florida, U.S.A. The MWAI framework is based on a statistical approach that seeks to reflect the continuous spatial and temporal variations of both water quantity and quality using a simple numerical index. Such a trend analysis will surely result in the final MWAI values for regional water management systems within a specified range. By using remote sensing technologies and data processing techniques, continuous monitoring of spatial and temporal distributions of key water availability variables, such as evapotranspiration (ET) and precipitation, is made achievable. These remote sensing technologies can be ground-based (e.g., radar estimates of rainfall), or based on remote sensing data gathered by aircraft or satellites. Using a middle term historical record, the MWAI was applied to the Manatee County water supplies. The findings clearly indicate that only eight out of twelve months in 2008 had positive MWAI values during the year. Such numerical findings are consistent with the observational evidence of statewide drought events in 2006-2008, which implies the time delay between the ending of severe drought period and the recovery of water availability in MWAI. It is expected that this forward-looking novel water availability forecasting platform will help provide a linkage in methodology between strategic planning, master planning, and the plant operation

Water use, availability, and net demand in the Tennessee River watershed within Alabama, 2005

USGS Publications Warehouse

Gill, Amy C.; Harper, Michael J.; Littlepage, Thomas M.

2013-01-01

The U.S. Geological Survey worked in cooperation with the Alabama Department of Economic and Community Affairs—Office of Water Resources to estimate water use and water availability for 2005 for the portion of the Tennessee River watershed contained within the borders of the State of Alabama. Estimates of water use and availability are an important part of planning for population and economic growth in the Tennessee River watershed in Alabama. Total water use for the region in 2005 was 5,197 million gallons per day (Mgal/d). Total surface-water withdrawals were 5,139 Mgal/d, and total groundwater withdrawals were about 58 Mgal/d. About 92 percent of the total water withdrawn was surface water used for once-through cooling for thermoelectric power generation. Self-supplied industrial and public-supply water uses accounted for the next greatest uses of water, constituting approximately 49 and 42 percent, respectively, of the total water use excluding thermoelectric power use. Summaries of water use by county and subbasin indicated the areas of greatest water withdrawals and use within the Tennessee River watershed. Limestone (2,012 Mgal/d), Jackson (1,498 Mgal/d), and Colbert (1,363 Mgal/d) Counties were the counties with the greatest total water use in 2005 and had large amounts of water withdrawn for thermoelectric power generation. When water use from thermoelectric power generation was not considered, the counties with the greatest withdrawals were Morgan (124 Mgal/d), Madison (72 Mgal/d), Colbert (69 Mgal/d), and Lawrence (67 Mgal/d). The subbasin with the greatest total water use was Wheeler Lake (2,260 Mgal/d) in the Middle Tennessee—Elk subregion. Wheeler Lake subbasin also had the greatest public-supply, irrigation, industrial, mining, and thermoelectric withdrawals of any subbasin in the Tennessee River watershed within Alabama. Total water availability for the Tennessee River watershed within Alabama was estimated to be 34,567 Mgal/d by the Geological

Water chemistry, seepage investigation, streamflow, reservoir storage, and annual availability of water for the San Juan-Chama Project, northern New Mexico, 1942-2010

USGS Publications Warehouse

McKean, Sarah E.; Anderholm, Scott K.

2014-01-01

at Azotea Tunnel Outlet occurred from May through June, with a median duration of slightly longer than a month. Years with higher maximum daily streamflow generally are associated with higher annual streamflow than years with lower maximum daily streamflow. The amount of water that can be diverted for the SJCP is controlled by the availability of streamflow and is limited by several factors including legal limits for diversion, limits from the SJCP infrastructure including the size of the diversion dams and tunnels, the capacity of Heron Reservoir, and operational constraints that limit when water can be diverted. The average annual streamflow at Azotea Tunnel Outlet was 94,710 acre-feet, and the annual streamflow at Azotea Tunnel Outlet was approximately 75 percent of the annual streamflow available for the SJCP. The average annual percentage of available streamflow not diverted for the SJCP was 14 percent because of structural limitations of the capacity of infrastructure, 1 percent because of limitations of the reservoir storage capacity, and 29 percent because of the limitations from operations. For most years, the annual available streamflow not diverted for unknown reasons exceeded the sum of the water not diverted because of structural, capacity, and operational limitations.

Understanding surface-water availability in the Central Valley as a means to projecting future groundwater storage with climate variability

NASA Astrophysics Data System (ADS)

Goodrich, J. P.; Cayan, D. R.

2017-12-01

California's Central Valley (CV) relies heavily on diverted surface water and groundwater pumping to supply irrigated agriculture. However, understanding the spatiotemporal character of water availability in the CV is difficult because of the number of individual farms and local, state, and federal agencies involved in using and managing water. Here we use the Central Valley Hydrologic Model (CVHM), developed by the USGS, to understand the relationships between climatic variability, surface water inputs, and resulting groundwater use over the historical period 1970-2013. We analyzed monthly surface water diversion data from >500 CV locations. Principle components analyses were applied to drivers constructed from meteorological data, surface reservoir storage, ET, land use cover, and upstream inflows, to feed multiple regressions and identify factors most important in predicting surface water diversions. Two thirds of the diversion locations ( 80% of total diverted water) can be predicted to within 15%. Along with monthly inputs, representations of cumulative precipitation over the previous 3 to 36 months can explain an additional 10% of variance, depending on location, compared to results that excluded this information. Diversions in the southern CV are highly sensitive to inter-annual variability in precipitation (R2 = 0.8), whereby more surface water is used during wet years. Until recently, this was not the case in the northern and mid-CV, where diversions were relatively constant annually, suggesting relative insensitivity to drought. In contrast, this has important implications for drought response in southern regions (eg. Tulare Basin) where extended dry conditions can severely limit surface water supplies and lead to excess groundwater pumping, storage loss, and subsidence. In addition to fueling our understanding of spatiotemporal variability in diversions, our ability to predict these water balance components allows us to update CVHM predictions before

Experimental evaluation of theoretical sea surface reflectance factors relevant to above-water radiometry.

PubMed

Zibordi, Giuseppe

2016-03-21

Determination of the water-leaving radiance L_W 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 L_W from the Ocean Color component of the Aerosol Robotic Network (AERONET-OC) with collocated L_W 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 L_W 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.

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.

Enhanced monitoring of the temporal and spatial relationships between water demand and water availability

NASA Astrophysics Data System (ADS)

Schneider, C. A.; Aggett, G. R.; Hattendorf, M. J.

2007-12-01

Better information on evapotranspiration (ET) is essential to better understanding of consumptive use of water by crops. RTi is using NASA Earth-sun System research results and METRIC (Mapping ET at high Resolution with Internalized Calibration) to increase the repeatability and accuracy of consumptive use estimates. METRIC, an image-processing model for calculating ET as a residual of the surface energy balance, utilizes the thermal band on various satellite remote sensors. Calculating actual ET from satellites can avoid many of the assumptions driving other methods of calculating ET over a large area. Because it is physically based and does not rely on explicit knowledge of crop type in the field, a large potential source of error should be eliminated. This paper assesses sources of error in current operational estimates of ET for an area of the South Platte irrigated lands of Colorado, and benchmarks potential improvements in the accuracy of ET estimates gained using METRIC, as well as the processing efficiency of consumptive use demand for large irrigated lands. Examples highlighting how better water planning decisions and water management can be achieved via enhanced monitoring of the temporal and spatial relationships between water demand and water availability are provided.

Viability of Commercially Available Bleach for Water Treatment in Developing Countries

PubMed Central

2009-01-01

Treating household water with low-cost, widely available commercial bleach is recommended by some organizations to improve water quality and reduce disease in developing countries. I analyzed the chlorine concentration of 32 bleaches from 12 developing countries; the average error between advertised and measured concentration was 35% (range = –45%–100%; standard deviation = 40%). Because of disparities between advertised and actual concentration, the use of commercial bleach for water treatment in developing countries is not recommended without ongoing quality control testing. PMID:19762657

Identification and assessment of potential water quality impact factors for drinking-water reservoirs.

PubMed

Gu, Qing; Deng, Jinsong; Wang, Ke; Lin, Yi; Li, Jun; Gan, Muye; Ma, Ligang; Hong, Yang

2014-06-10

Various reservoirs have been serving as the most important drinking water sources in Zhejiang Province, China, due to the uneven distribution of precipitation and severe river pollution. Unfortunately, rapid urbanization and industrialization have been continuously challenging the water quality of the drinking-water reservoirs. The identification and assessment of potential impacts is indispensable in water resource management and protection. This study investigates the drinking water reservoirs in Zhejiang Province to better understand the potential impact on water quality. Altogether seventy-three typical drinking reservoirs in Zhejiang Province encompassing various water storage levels were selected and evaluated. Using fifty-two reservoirs as training samples, the classification and regression tree (CART) method and sixteen comprehensive variables, including six sub-sets (land use, population, socio-economy, geographical features, inherent characteristics, and climate), were adopted to establish a decision-making model for identifying and assessing their potential impacts on drinking-water quality. The water quality class of the remaining twenty-one reservoirs was then predicted and tested based on the decision-making model, resulting in a water quality class attribution accuracy of 81.0%. Based on the decision rules and quantitative importance of the independent variables, industrial emissions was identified as the most important factor influencing the water quality of reservoirs; land use and human habitation also had a substantial impact on water quality. The results of this study provide insights into the factors impacting the water quality of reservoirs as well as basic information for protecting reservoir water resources.

Long term growth responses of loblolly pine to optimal nutrient and water resource availability

Treesearch

Timothy J. Albaugh; H. Lee Allen; Phillip M. Dougherty; Kurt H. Johnsen

2004-01-01

A factorial combination of four treatments (control (CW), optimal growing season water availability (IW), optimum nutrient availability (FW), and combined optimum water and nutrient availability (FIW)) in four replications were initiated in an 8-year- old Pinus taeda stand growing on a droughty, nutrient-poor, sandy site in Scotland County, NC and...

Water availability and environmental temperature correlate with geographic variation in water balance in common lizards.

PubMed

Dupoué, Andréaz; Rutschmann, Alexis; Le Galliard, Jean François; Miles, Donald B; Clobert, Jean; DeNardo, Dale F; Brusch, George A; Meylan, Sandrine

2017-12-01

Water conservation strategies are well documented in species living in water-limited environments, but physiological adaptations to water availability in temperate climate environments are still relatively overlooked. Yet, temperate species are facing more frequent and intense droughts as a result of climate change. Here, we examined variation in field hydration state (plasma osmolality) and standardized evaporative water loss rate (SEWL) of adult male and pregnant female common lizards (Zootoca vivipara) from 13 natural populations with contrasting air temperature, air humidity, and access to water. We found different patterns of geographic variation between sexes. Overall, males were more dehydrated (i.e. higher osmolality) than pregnant females, which likely comes from differences in field behaviour and water intake since the rate of SEWL was similar between sexes. Plasma osmolality and SEWL rate were positively correlated with environmental temperature in males, while plasma osmolality in pregnant females did not correlate with environmental conditions, reproductive stage or reproductive effort. The SEWL rate was significantly lower in populations without access to free standing water, suggesting that lizards can adapt or adjust physiology to cope with habitat dryness. Environmental humidity did not explain variation in water balance. We suggest that geographic variation in water balance physiology and behaviour should be taken account to better understand species range limits and sensitivity to climate change.

Metabolomic response of Calotropis procera growing in the desert to changes in water availability.

PubMed

Ramadan, Ahmed; Sabir, Jamal S M; Alakilli, Saleha Y M; Shokry, Ahmed M; Gadalla, Nour O; Edris, Sherif; Al-Kordy, Magdy A; Al-Zahrani, Hassan S; El-Domyati, Fotouh M; Bahieldin, Ahmed; Baker, Neil R; Willmitzer, Lothar; Irgang, Susann

2014-01-01

Water availability is a major limitation for agricultural productivity. Plants growing in severe arid climates such as deserts provide tools for studying plant growth and performance under extreme drought conditions. The perennial species Calotropis procera used in this study is a shrub growing in many arid areas which has an exceptional ability to adapt and be productive in severe arid conditions. We describe the results of studying the metabolomic response of wild C procera plants growing in the desert to a one time water supply. Leaves of C. procera plants were taken at three time points before and 1 hour, 6 hours and 12 hours after watering and subjected to a metabolomics and lipidomics analysis. Analysis of the data reveals that within one hour after watering C. procera has already responded on the metabolic level to the sudden water availability as evidenced by major changes such as increased levels of most amino acids, a decrease in sucrose, raffinose and maltitol, a decrease in storage lipids (triacylglycerols) and an increase in membrane lipids including photosynthetic membranes. These changes still prevail at the 6 hour time point after watering however 12 hours after watering the metabolomics data are essentially indistinguishable from the prewatering state thus demonstrating not only a rapid response to water availability but also a rapid response to loss of water. Taken together these data suggest that the ability of C. procera to survive under the very harsh drought conditions prevailing in the desert might be associated with its rapid adjustments to water availability and losses.

Metabolomic Response of Calotropis procera Growing in the Desert to Changes in Water Availability

PubMed Central

Ramadan, Ahmed; Sabir, Jamal S. M.; Alakilli, Saleha Y. M.; Shokry, Ahmed M.; Gadalla, Nour O.; Edris, Sherif; Al-Kordy, Magdy A.; Al-Zahrani, Hassan S.; El-Domyati, Fotouh M.; Bahieldin, Ahmed; Baker, Neil R.; Willmitzer, Lothar; Irgang, Susann

2014-01-01

Water availability is a major limitation for agricultural productivity. Plants growing in severe arid climates such as deserts provide tools for studying plant growth and performance under extreme drought conditions. The perennial species Calotropis procera used in this study is a shrub growing in many arid areas which has an exceptional ability to adapt and be productive in severe arid conditions. We describe the results of studying the metabolomic response of wild C procera plants growing in the desert to a one time water supply. Leaves of C. procera plants were taken at three time points before and 1 hour, 6 hours and 12 hours after watering and subjected to a metabolomics and lipidomics analysis. Analysis of the data reveals that within one hour after watering C. procera has already responded on the metabolic level to the sudden water availability as evidenced by major changes such as increased levels of most amino acids, a decrease in sucrose, raffinose and maltitol, a decrease in storage lipids (triacylglycerols) and an increase in membrane lipids including photosynthetic membranes. These changes still prevail at the 6 hour time point after watering however 12 hours after watering the metabolomics data are essentially indistinguishable from the prewatering state thus demonstrating not only a rapid response to water availability but also a rapid response to loss of water. Taken together these data suggest that the ability of C. procera to survive under the very harsh drought conditions prevailing in the desert might be associated with its rapid adjustments to water availability and losses. PMID:24520340

Water Availability for Synthetic Fuels: An Assessment of Current Studies

DOT National Transportation Integrated Search

1982-10-01

The objective of this study is to describe and analyze the hydrologic, institutional, legal, and economic issues involved in assessing and interpreting estimates of water availability for synfuels development in four major river basins: (1) Upper Mis...

Water availability and genetic effects on wood properties of loblolly pine (Pinus taeda)

Treesearch

C. A. Gonzalez-Benecke; T. A. Martin; Alexander Clark; G. F. Peter

2010-01-01

We studied the effect of water availability on basal area growth and wood properties of 11-year-old loblolly pine (Pinus taeda L.) trees from contrasting Florida (FL) (a mix of half-sib families) and South Carolina coastal plain (SC) (a single, half-sib family) genetic material. Increasing soil water availability via irrigation increased average wholecore specific...

Exploring the Influence of Smallholders' Perceptions Regarding Water Availability on Crop Choice and Water Allocation Through Socio-Hydrological Modeling

NASA Astrophysics Data System (ADS)

Kuil, L.; Evans, T.; McCord, P. F.; Salinas, J. L.; Blöschl, G.

2018-04-01

While it is known that farmers adopt different decision-making behaviors to cope with stresses, it remains challenging to capture this diversity in formal model frameworks that are used to advance theory and inform policy. Guided by cognitive theory and the theory of bounded rationality, this research develops a novel, socio-hydrological model framework that can explore how a farmer's perception of water availability impacts crop choice and water allocation. The model is informed by a rich empirical data set at the household level collected during 2013 in Kenya's Upper Ewaso Ng'iro basin that shows that the crop type cultivated is correlated with water availability. The model is able to simulate this pattern and shows that near-optimal or "satisficing" crop patterns can emerge also when farmers were to make use of simple decision rules and have diverse perceptions on water availability. By focusing on farmer decision making it also captures the rebound effect, i.e., as additional water becomes available through the improvement of crop efficiencies it will be reallocated on the farm instead of flowing downstream, as a farmer will adjust his (her) water allocation and crop pattern to the new water conditions. This study is valuable as it is consistent with the theory of bounded rationality, and thus offers an alternative, descriptive model in addition to normative models. The framework can be used to understand the potential impact of climate change on the socio-hydrological system, to simulate and test various assumptions regarding farmer behavior and to evaluate policy interventions.

Water Availability and Use Pilot-A multiscale assessment in the U.S. Great Lakes Basin

USGS Publications Warehouse

Reeves, Howard W.

2011-01-01

Beginning in 2005, water availability and use were assessed for the U.S. part of the Great Lakes Basin through the Great Lakes Basin Pilot of a U.S. Geological Survey (USGS) national assessment of water availability and use. The goals of a national assessment of water availability and use are to clarify our understanding of water-availability status and trends and improve our ability to forecast the balance between water supply and demand for future economic and environmental uses. This report outlines possible approaches for full-scale implementation of such an assessment. As such, the focus of this study was on collecting, compiling, and analyzing a wide variety of data to define the storage and dynamics of water resources and quantify the human demands on water in the Great Lakes region. The study focused on multiple spatial and temporal scales to highlight not only the abundant regional availability of water but also the potential for local shortages or conflicts over water. Regional studies provided a framework for understanding water resources in the basin. Subregional studies directed attention to varied aspects of the water-resources system that would have been difficult to assess for the whole region because of either data limitations or time limitations for the project. The study of local issues and concerns was motivated by regional discussions that led to recent legislative action between the Great Lakes States and regional cooperation with the Canadian Great Lakes Provinces. The multiscale nature of the study findings challenges water-resource managers and the public to think about regional water resources in an integrated way and to understand how future changes to the system-driven by human uses, climate variability, or land-use change-may be accommodated by informed water-resources management.

Influences of climate change on water resources availability in Jinjiang Basin, China.

PubMed

Sun, Wenchao; Wang, Jie; Li, Zhanjie; Yao, Xiaolei; Yu, Jingshan

2014-01-01

The influences of climate change on water resources availability in Jinjiang Basin, China, were assessed using the Block-wise use of the TOPmodel with the Muskingum-Cunge routing method (BTOPMC) distributed hydrological model. The ensemble average of downscaled output from sixteen GCMs (General Circulation Models) for A1B emission scenario (medium CO2 emission) in the 2050s was adopted to build regional climate change scenario. The projected precipitation and temperature data were used to drive BTOPMC for predicting hydrological changes in the 2050s. Results show that evapotranspiration will increase in most time of a year. Runoff in summer to early autumn exhibits an increasing trend, while in the rest period of a year it shows a decreasing trend, especially in spring season. From the viewpoint of water resource availability, it is indicated that it has the possibility that water resources may not be sufficient to fulfill irrigation water demand in the spring season and one possible solution is to store more water in the reservoir in previous summer.

Influences of Climate Change on Water Resources Availability in Jinjiang Basin, China

PubMed Central

Wang, Jie; Li, Zhanjie; Yao, Xiaolei

2014-01-01

The influences of climate change on water resources availability in Jinjiang Basin, China, were assessed using the Block-wise use of the TOPmodel with the Muskingum-Cunge routing method (BTOPMC) distributed hydrological model. The ensemble average of downscaled output from sixteen GCMs (General Circulation Models) for A1B emission scenario (medium CO2 emission) in the 2050s was adopted to build regional climate change scenario. The projected precipitation and temperature data were used to drive BTOPMC for predicting hydrological changes in the 2050s. Results show that evapotranspiration will increase in most time of a year. Runoff in summer to early autumn exhibits an increasing trend, while in the rest period of a year it shows a decreasing trend, especially in spring season. From the viewpoint of water resource availability, it is indicated that it has the possibility that water resources may not be sufficient to fulfill irrigation water demand in the spring season and one possible solution is to store more water in the reservoir in previous summer. PMID:24701192

Lake-level variability and water availability in the Great Lakes

USGS Publications Warehouse

Wilcox, Douglas A.; Thompson, Todd A.; Booth, Robert K.; Nicholas, J.R.

2007-01-01

In this report, we present recorded and reconstructed (pre-historical) changes in water levels in the Great Lakes, relate them to climate changes of the past, and highlight major water-availability implications for storage, coastal ecosystems, and human activities. 'Water availability,' as conceptualized herein, includes a recognition that water must be available for human and natural uses, but the balancing of how much should be set aside for which use is not discussed. The Great Lakes Basin covers a large area of North America. The lakes capture and store great volumes of water that are critical in maintaining human activities and natural ecosystems. Water enters the lakes mostly in the form of precipitation and streamflow. Although flow through the connecting channels is a primary output from the lakes, evaporation is also a major output. Water levels in the lakes vary naturally on timescales that range from hours to millennia; storage of water in the lakes changes at the seasonal to millennial scales in response to lake-level changes. Short-term changes result from storm surges and seiches and do not affect storage. Seasonal changes are driven by differences in net basin supply during the year related to snowmelt, precipitation, and evaporation. Annual to millennial changes are driven by subtle to major climatic changes affecting both precipitation (and resulting streamflow) and evaporation. Rebounding of the Earth's surface in response to loss of the weight of melted glaciers has differentially affected water levels. Rebound rates have not been uniform across the basin, causing the hydrologic outlet of each lake to rise in elevation more rapidly than some parts of the coastlines. The result is a long-term change in lake level with respect to shoreline features that differs from site to site. The reconstructed water-level history of Lake Michigan-Huron over the past 4,700 years shows three major high phases from 2,300 to 3,300, 1,100 to 2,000, and 0 to 800

Shifting species interactions in terrestrial dryland ecosystems under altered water availability and climate change

USGS Publications Warehouse

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

Shifting species interactions in terrestrial dryland ecosystems under altered water availability and climate change.

PubMed

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

Reassessment of Ground-Water Recharge and Simulated Ground-Water Availability for the Hawi Area of North Kohala, Hawaii

USGS Publications Warehouse

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

When vegetation change alters ecosystem water availability.

PubMed

Scott, Russell L; Huxman, Travis E; Barron-Gafford, Greg A; Darrel Jenerette, G; Young, Jessica M; Hamerlynck, Erik P

2014-07-01

The combined effects of vegetation and climate change on biosphere-atmosphere water vapor (H2 O) and carbon dioxide (CO2 ) exchanges are expected to vary depending, in part, on how biotic activity is controlled by and alters water availability. This is particularly important when a change in ecosystem composition alters the fractional covers of bare soil, grass, and woody plants so as to influence the accessibility of shallower vs. deeper soil water pools. To study this, we compared 5 years of eddy covariance measurements of H2 O and CO2 fluxes over a riparian grassland, shrubland, and woodland. In comparison with the surrounding upland region, groundwater access at the riparian sites increased net carbon uptake (NEP) and evapotranspiration (ET), which were sustained over more of the year. Among the sites, the grassland used less of the stable groundwater resource, and increasing woody plant density decoupled NEP and ET from incident precipitation (P), resulting in greater exchange rates that were less variable year to year. Despite similar gross patterns, how groundwater accessibility affected NEP was more complex than ET. The grassland had higher respiration (Reco ) costs. Thus, while it had similar ET and gross carbon uptake (GEP) to the shrubland, grassland NEP was substantially less. Also, grassland carbon fluxes were more variable due to occasional flooding at the site, which both stimulated and inhibited NEP depending upon phenology. Woodland NEP was large, but surprisingly similar to the less mature, sparse shrubland, even while having much greater GEP. Woodland Reco was greater than the shrubland and responded strongly and positively to P, which resulted in a surprising negative NEP response to P. This is likely due to the large accumulation of carbon aboveground and in the surface soil. These long-term observations support the strong role that water accessibility can play when determining the consequences of ecosystem vegetation change. © 2013 John Wiley

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.

Identification and Assessment of Potential Water Quality Impact Factors for Drinking-Water Reservoirs

PubMed Central

Gu, Qing; Deng, Jinsong; Wang, Ke; Lin, Yi; Li, Jun; Gan, Muye; Ma, Ligang; Hong, Yang

2014-01-01

Various reservoirs have been serving as the most important drinking water sources in Zhejiang Province, China, due to the uneven distribution of precipitation and severe river pollution. Unfortunately, rapid urbanization and industrialization have been continuously challenging the water quality of the drinking-water reservoirs. The identification and assessment of potential impacts is indispensable in water resource management and protection. This study investigates the drinking water reservoirs in Zhejiang Province to better understand the potential impact on water quality. Altogether seventy-three typical drinking reservoirs in Zhejiang Province encompassing various water storage levels were selected and evaluated. Using fifty-two reservoirs as training samples, the classification and regression tree (CART) method and sixteen comprehensive variables, including six sub-sets (land use, population, socio-economy, geographical features, inherent characteristics, and climate), were adopted to establish a decision-making model for identifying and assessing their potential impacts on drinking-water quality. The water quality class of the remaining twenty-one reservoirs was then predicted and tested based on the decision-making model, resulting in a water quality class attribution accuracy of 81.0%. Based on the decision rules and quantitative importance of the independent variables, industrial emissions was identified as the most important factor influencing the water quality of reservoirs; land use and human habitation also had a substantial impact on water quality. The results of this study provide insights into the factors impacting the water quality of reservoirs as well as basic information for protecting reservoir water resources. PMID:24919129

77 FR 27770 - Clean Water Act Section 303(d): Availability of List Decisions

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-11

... ENVIRONMENTAL PROTECTION AGENCY [FRL-9670-5] Clean Water Act Section 303(d): Availability of List...: This notice announces EPA's decision identifying certain water quality limited waterbodies, and the associated pollutant, in Utah to be listed pursuant to the Clean Water Act Section 303(d)(2), and requests...

Climate change impacts on water availability in the Red River Basin and critical areas for future water conservation

NASA Astrophysics Data System (ADS)

Zamani Sabzi, H.; Moreno, H. A.; Neeson, T. M.; Rosendahl, D. H.; Bertrand, D.; Xue, X.; Hong, Y.; Kellog, W.; Mcpherson, R. A.; Hudson, C.; Austin, B. N.

2017-12-01

Previous periods of severe drought followed by exceptional flooding in the Red River Basin (RRB) have significantly affected industry, agriculture, and the environment in the region. Therefore, projecting how climate may change in the future and being prepared for potential impacts on the RRB is crucially important. In this study, we investigated the impacts of climate change on water availability across the RRB. We used three down-scaled global climate models and three potential greenhouse gas emission scenarios to assess precipitation, temperature, streamflow and lake levels throughout the RRB from 1961 to 2099 at a spatial resolution of 1/10°. Unit-area runoff and streamflow were obtained using the Variable Infiltration Capacity (VIC) model applied across the entire basin. We found that most models predict less precipitation in the western side of the basin and more in the eastern side. In terms of temperature, the models predict that average temperature could increase as much as 6°C. Most models project slightly more precipitation and streamflow values in the future, specifically in the eastern side of the basin. Finally, we analyzed the projected meteorological and hydrologic parameters alongside regional water demand for different sectors to identify the areas on the RRB that will need water-environmental conservation actions in the future. These hotspots of future low water availability are locations where regional environmental managers, water policy makers, and the agricultural and industrial sectors must proactively prepare to deal with declining water availability over the coming decades.

Water Availability Indices – A Literature Review

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

Xu, Hui; Wu, May M.

Fresh water is a critical resource for humanity and the ecosystem. In general, water resources can be partitioned into two major categories: blue water and green water (Falkenmark and Rockström 2006). Precipitation that runs off or percolates into the deep aquifer is defined as blue water, and precipitation that filtrates into soil, which eventually returns to the atmosphere as evaporation, is called green water (Hoekstra et al. 2011). For human purposes, green water is almost exclusively used for agricultural production, but blue water can be used for multiple competing sectors, such as irrigation and municipal water.

Availability of ground water in the lower Pawcatuck River basin, Rhode Island

USGS Publications Warehouse

Gonthier, Joseph B.; Johnston, Herbert E.; Malmberg, Glenn T.

1974-01-01

The lower Pawcatuck River basin in southwestern Rhode Island is an area of about 169 square miles underlain by crystalline bedrock over which lies a relatively thin mantle of glacial till and stratified drift. Stratified drift, consisting dominantly of sand and gravel, occurs in irregularly shaped linear deposits that are generally less than a mile wide and less than 125 feet thick; these deposits are found along the Pawcatuck River, its tributaries, and abandoned preglacial channels. Deposits of stratified sand and gravel constitute the principal aquifer in the lower Pawcatuck basin and the only one capable of sustaining yields of 100 gallons per minute or more to individual wells. Water available for development in this aquifer consists of water in storage--potential ground-water runoff to streams--plus infiltration that can be induced from streams. Minimum annual ground-water runoff from the sand and gravel aquifer is calculated to be at least 1.17 cubic feet per second per square mile, or 0.76 million gallons per day per square mile. Potential recharge by induced infiltration is estimated to range from about 250 to 600 gallons per day per linear foot of streambed for the principal streams. In most areas, induced infiltration from streams constitutes the major source of water potentially available for development by wells. Because subsurface hydraulic connection in the sand and gravel aquifer is poor in several places, the deposits are conveniently divisible into several ground-water reservoirs. The potential yield from five of the most promising ground-water reservoirs is evaluated by means of mathematical models. Results indicate that continuous withdrawals ranging from 1.3 to 10.3 million gallons per day, and totaling 31 million gallons per day, are obtainable from these reservoirs. Larger yields may be recovered by different well placement, spacing, construction and development, pumping practice, and so forth. Withdrawals at the rates indicated will reduce

Distribution and Availability of State and Areawide Water Quality Reports in Oklahoma Libraries.

ERIC Educational Resources Information Center

McClure, Charles R.; Million, Anne

This report examines the distribution and availability of water quality reports in the state of Oklahoma. Based on legislation from the Clean Water Act and regulations from the Environmental Protection Agency's "Public Participation Handbook for Water Quality Management," depository libraries must be established to provide citizen access to…

Modeling of Soil Water Availability for Agricultural Planning at Pelaga Village, Badung Regency, Bali, Indonesia

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.

Biological Soil Crusts of Arctic Svalbard-Water Availability as Potential Controlling Factor for Microalgal Biodiversity.

PubMed

Borchhardt, Nadine; Baum, Christel; Mikhailyuk, Tatiana; Karsten, Ulf

2017-01-01

In the present study the biodiversity of biological soil crusts (BSCs) formed by phototrophic organisms were investigated on Arctic Svalbard (Norway). These communities exert several important ecological functions and constitute a significant part of vegetation at high latitudes. Non-diatom eukaryotic microalgal species of BSCs from 20 sampling stations around Ny-Ålesund and Longyearbyen were identified by morphology using light microscopy, and the results revealed a high species richness with 102 species in total. 67 taxa belonged to Chlorophyta (31 Chlorophyceae and 36 Trebouxiophyceae), 13 species were Streptophyta (11 Klebsormidiophyceae and two Zygnematophyceae) and 22 species were Ochrophyta (two Eustigmatophyceae and 20 Xanthophyceae). Surprisingly, Klebsormidium strains belonging to clade G (Streptophyta), which were so far described from Southern Africa, could be determined at 5 sampling stations. Furthermore, comparative analyses of Arctic and Antarctic BSCs were undertaken to outline differences in species composition. In addition, a pedological analysis of BSC samples included C, N, S, TP (total phosphorus), and pH measurements to investigate the influence of soil properties on species composition. No significant correlation with these chemical soil parameters was confirmed but the results indicated that pH might affect the BSCs. In addition, a statistically significant influence of precipitation on species composition was determined. Consequently, water availability was identified as one key driver for BSC biodiversity in Arctic regions.

76 FR 62061 - Clean Water Act Section 303(d): Availability of List Decisions

Federal Register 2010, 2011, 2012, 2013, 2014

2011-10-06

... ENVIRONMENTAL PROTECTION AGENCY [FRL-9475-4] Clean Water Act Section 303(d): Availability of List... three waterbodies. These three waterbodies were added by EPA because the applicable numeric water... be obtained at EPA Region 6's Web site at http://www.epa.gov/region6/water/npdes/tmdl/index.htm...

Ozone risk assessment in three oak species as affected by soil water availability.

PubMed

Hoshika, Yasutomo; Moura, Barbara; Paoletti, Elena

2018-03-01

To derive ozone (O 3 ) dose-response relationships for three European oak species (Quercus ilex, Quercus pubescens, and Quercus robur) under a range of soil water availability, an experiment was carried out with 2-year-old potted seedlings exposed to three levels of water availability in the soil and three levels of O 3 pollution for one growing season in an ozone free-air controlled exposure (FACE) facility. Total biomass losses were estimated relative to a hypothetical clean air at the pre-industrial age, i.e., at 10 ppb as daily average (M24). A stomatal conductance model was parameterized with inputs from the three species for calculating the stomatal O 3 flux. Exposure-based (M24, W126, and AOT40) and flux-based (phytotoxic O 3 dose (POD) 0-3 ) dose-response relationships were estimated and critical levels (CL) were calculated for a 5% decline of total biomass. Results show that water availability can significantly affect O 3 risk assessment. In fact, dose-response relationships calculated per individual species at each water availability level resulted in very different CLs and best metrics. In a simplified approach where species were aggregated on the basis of their O 3 sensitivity, the best metric was POD 0.5 , with a CL of 6.8 mmol m -2 for the less O 3 -sensitive species Q. ilex and Q. pubescens and of 3.5 mmol m -2 for the more O 3 -sensitive species Q. robur. The performance of POD 0 , however, was very similar to that of POD 0.5 , and thus a CL of 6.9 mmol m -2 POD 0 and 3.6 mmol m -2 POD 0 for the less and more O 3 -sensitive oak species may be also recommended. These CLs can be applied to oak ecosystems at variable water availability in the soil. We conclude that POD y is able to reconcile the effects of O 3 and soil water availability on species-specific oak productivity.

Concepts for national assessment of water availability and use

USGS Publications Warehouse

,

2002-01-01

In response to a directive from Congress to the U.S. Geological Survey to 'prepare a report describing the scope and magnitude of the efforts needed to provide periodic assessments of the status and trends in the availability and use of freshwater resources,' of the United States, a program is proposed to develop and report on indicators of the status and trends in storage volume, flow rates, and uses of water nationwide. This program would be analogous to the task of other Federal statistical programs that produce and regularly update indicator variables that describe economic, demographic, and health conditions of the Nation. The assessment also would provide regional estimates of recharge, evapotranspiration, interbasin transfers, and other components of the water cycle.

Dynamic aspects of soil water availability for isohydric plants: Focus on root hydraulic resistances

NASA Astrophysics Data System (ADS)

Couvreur, V.; Vanderborght, J.; Draye, X.; Javaux, M.

2014-11-01

Soil water availability for plant transpiration is a key concept in agronomy. The objective of this study is to revisit this concept and discuss how it may be affected by processes locally influencing root hydraulic properties. A physical limitation to soil water availability in terms of maximal flow rate available to plant leaves (Qavail) is defined. It is expressed for isohydric plants, in terms of plant-centered variables and properties (the equivalent soil water potential sensed by the plant, ψs eq; the root system equivalent conductance, Krs; and a threshold leaf water potential, ψleaf lim). The resulting limitation to plant transpiration is compared to commonly used empirical stress functions. Similarities suggest that the slope of empirical functions might correspond to the ratio of Krs to the plant potential transpiration rate. The sensitivity of Qavail to local changes of root hydraulic conductances in response to soil matric potential is investigated using model simulations. A decrease of radial conductances when the soil dries induces earlier water stress, but allows maintaining higher night plant water potentials and higher Qavail during the last week of a simulated 1 month drought. In opposition, an increase of radial conductances during soil drying provokes an increase of hydraulic redistribution and Qavail at short term. This study offers a first insight on the effect of dynamic local root hydraulic properties on soil water availability. By better understanding complex interactions between hydraulic processes involved in soil-plant hydrodynamics, better prospects on how root hydraulic traits mitigate plant water stress might be achieved.

Aggregating available soil water holding capacity data for crop yield models

NASA Technical Reports Server (NTRS)

Seubert, C. E.; Daughtry, C. S. T.; Holt, D. A.; Baumgardner, M. F.

1984-01-01

The total amount of water available to plants that is held against gravity in a soil is usually estimated as the amount present at -0.03 MPa average water potential minus the amount present at -1.5 MPa water potential. This value, designated available water-holding capacity (AWHC), is a very important soil characteristic that is strongly and positively correlated to the inherent productivity of soils. In various applications, including assessing soil moisture status over large areas, it is necessary to group soil types or series as to their productivity. Current methods to classify AWHC of soils consider only total capacity of soil profiles and thus may group together soils which differ greatly in AWHC as a function of depth in the profile. A general approach for evaluating quantitatively the multidimensional nature of AWHC in soils is described. Data for 902 soil profiles, representing 184 soil series, in Indiana were obtained from the Soil Characterization Laboratory at Purdue University. The AWHC for each of ten 150-mm layers in each soil was established, based on soil texture and parent material. A multivariate clustering procedure was used to classify each soil profile into one of 4, 8, or 12 classes based upon ten-dimensional AWHC values. The optimum number of classes depends on the range of AWHC in the population of oil profiles analyzed and on the sensitivity of a crop to differences in distribution of water within the soil profile.

Water quality degradation effects on freshwater availability: Impacts to human activities

USGS Publications Warehouse

Peters, N.E.; Meybeck, Michel

2000-01-01

The quality of freshwater at any point on the landscape reflects the combined effects of many processes along water pathways. Human activities on all spatial scales affect both water quality and quantity. Alteration of the landscape and associated vegetation has not only changed the water balance, but typically has altered processes that control water quality. Effects of human activities on a small scale are relevant to an entire drainage basin. Furthermore, local, regional, and global differences in climate and water flow are considerable, causing varying effects of human activities on land and water quality and quantity, depending on location within a watershed, geology, biology, physiographic characteristics, and climate. These natural characteristics also greatly control human activities, which will, in turn, modify (or affect) the natural composition of water. One of the most important issues for effective resource management is recognition of cyclical and cascading effects of human activities on the water quality and quantity along hydrologic pathways. The degradation of water quality in one part of a watershed can have negative effects on users downstream. Everyone lives downstream of the effects of some human activity. An extremely important factor is that substances added to the atmosphere, land, and water generally have relatively long time scales for removal or clean up. The nature of the substance, including its affinity for adhering to soil and its ability to be transformed, affects the mobility and the time scale for removal of the substance. Policy alone will not solve many of the degradation issues, but a combination of policy, education, scientific knowledge, planning, and enforcement of applicable laws can provide mechanisms for slowing the rate of degradation and provide human and environmental protection. Such an integrated approach is needed to effectively manage land and water resources.

Effects of available water on growth and competition of southern pine beetle associated fungi

Treesearch

Kier D. Klepzig; J. Flores-Otero; R.W. Hofstetter; M.P. Ayers

2004-01-01

Competitive interactions among bark beetle associated fungi are potentially influenced by abiotic factors. Water potential, in particular, undergoes marked changes over the course of beetle colonization of tree hosts. To investigate the impact of water potential on competition among three southern pine beetle associated fungi, Ophiostoma minus,

Availability of water affects renewal of tissues in migratory blackcaps during stopover.

PubMed

Mizrahy, Ortal; Bauchinger, Ulf; Aamidor, Sarah E; McWilliams, Scott R; Pinshow, Berry

2011-09-01

Migrating blackcaps (Sylvia atricapilla) were used to test the predictions that (1) the rebuilding of the digestive tract, as reflected by mass-specific consumption of food on the first 2-3 days of a stopover, is faster in birds with access to drinking water than in birds without, and (2) that adipose tissue and pectoral muscles grow faster and to a greater extent in birds with unlimited access to water. We simulated migratory stopover in two experiments. In Experiment I, each of 31 birds was randomly assigned to one of three experimental groups for 6 days. Along with mealworms (∼64% water) ad libitum, Group 1 received drinking water ad libitum; Group 2 had 0.5 h/day access to water; and Group 3 had no access to water. In Experiment II, 30 birds were offered a mixed diet for insectivorous birds (∼33% water) ad libitum for 6 days, while randomly assigned to two groups: (1) Water ad libitum-control; and (2) 30 min access to water twice a day. We measured lean mass and fat mass using dual energy X-ray absorptiometry, as well as body mass (m(b)), pectoral muscle index (PMI), and daily intake of food and water. Mean daily water intake was significantly different among the groups in both experiments. However, the availability of drinking water positively affected the rates of gain of lean and fat mass only in birds fed with the mixed, relatively dry diet. Furthermore, mass-specific daily food intake was affected by the availability of drinking water only in the mixed diet experiment, in which birds with unlimited access to drinking water reached an asymptote, 1 day earlier than birds in the water-restricted group. We suggest that in birds consuming diets with low water content, the lack of sufficient drinking water may result in slower rebuilding of the digestive tract, or may influence biochemical processes in the gut that result in slower growth of tissue. Although blackcaps obtained sufficient water from preformed and metabolic water to renew lost tissues when

Assessing groundwater availability in the Northern Atlantic Coastal Plain aquifer system

USGS Publications Warehouse

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.

[Phosphorus availability in cropland soils of China and related affecting factors].

PubMed

Wang, Yong-Zhuang; Chen, Xin; Shi, Yi

2013-01-01

Soil phosphorus (P) availability directly determines cropland productivity. Based on the long-term fertilization experiments in different climatic zones of China, this paper summarized the P content, its availability, and the factors affecting the P transformation in China cropland soils. The total and available P contents in different types of China cropland soils were 0.31-1.72 g x kg(-1) and 0.1-228.8 mg x kg(-1), respectively. Soil parent material, soil physical and chemical prosperities, and fertilization practices were the main factors affecting the soil P availability. It was suggested that more attentions should be paid on the mixed application of organic manure and chemical fertilizers to improve the P availability of cropland soils and on the potential environmental impacts of this fertilization.

Plant roots use a patterning mechanism to position lateral root branches toward available water.

PubMed

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.

Middle-term Metropolitan Water Availability Index Assessment Based on Synergistic Potentials of Multi-sensor Data

EPA Science Inventory

The impact of recent drought and water pollution episodes results in an acute need to project future water availability to assist water managers in water utility infrastructure management within many metropolitan regions. Separate drought and water quality indices previously deve...

Identification of the effective water availability from streamflows in the Zerafshan river basin, Central Asia

NASA Astrophysics Data System (ADS)

Olsson, Oliver; Gassmann, Matthias; Wegerich, Kai; Bauer, Melanie

2010-09-01

SummaryQuantitative estimates of the hydrologic effects of climate change are essential for understanding and solving potential transboundary water conflicts in the Zerafshan river basin, Central Asia. This paper introduces an identification of runoff generation processes and a detection of changes in hydrological regimes supporting Mann-Kendall trend analysis for streamflows. By this, the effective available and future water resources are identified for the Zerafshan. The results for the subbasins in the upper Zerafshan and for the reference station at the upper catchment outlet indicate that glacier melt is the most significant component of river runoff. The Mann-Kendall trend analysis confirms the regime analysis with the shift in the seasonality of the discharge. Furthermore, the results of the Kendall-Theil Robust Line for predicted long-term discharge trends show a decreasing annual discharge. The experience gained during this study emphasizes the fact that the summer flood, urgently required for the large irrigation projects downstream in Uzbekistan, is reduced and more water will be available in spring. Additionally, following the estimation of future discharges in 50 and 100 years the hydrological changes are affecting the seasonal water availability for irrigation. This analysis highlighted that water availability is decreasing and the timing of availability is changing. Hence, there will be more competition between upstream Tajikistan and downstream Uzbekistan. Planned projects within the basin might have to be reconsidered and the changed scenario of water availability needs to be properly taken into account for long-term basin scale water management.

Polder effects on sediment-to-soil conversion: water table, residual available water capacity, and salt stress interdependence.

PubMed

Radimy, Raymond Tojo; Dudoignon, Patrick; Hillaireau, Jean Michel; Deboute, Elise

2013-01-01

The French Atlantic marshlands, reclaimed since the Middle Age, have been successively used for extensive grazing and more recently for cereal cultivation from 1970. The soils have acquired specific properties which have been induced by the successive reclaiming and drainage works and by the response of the clay dominant primary sediments, that is, structure, moisture, and salinity profiles. Based on the whole survey of the Marais Poitevin and Marais de Rochefort and in order to explain the mechanisms of marsh soil behavior, the work focuses on two typical spots: an undrained grassland since at least 1964 and a drained cereal cultivated field. The structure-hydromechanical profiles relationships have been established thanks to the clay matrix shrinkage curve. They are confronted to the hydraulic functioning including the fresh-to-salt water transfers and to the recording of tensiometer profiles. The CE1/5 profiles supply the water geochemical and geophysical data by their better accuracy. Associated to the available water capacity calculation they allow the representation of the parallel evolution of the residual available water capacity profiles and salinity profiles according to the plant growing and rooting from the mesophile systems of grassland to the hygrophile systems of drained fields.

Root-zone temperature and water availability affect early root growth of planted longleaf pine

Treesearch

M.A. Sword

1995-01-01

Longleaf pine seedlings from three seed sources were exposed to three root-zone temperatures and three levels of water availability for 28 days. Root growth declined as temperature and water availability decreased. Root growth differed by seed source. Results suggest that subtle changes in the regeneration environment may influence early root growth of longleaf pine...

Vegetative response to water availability on the San Carlos Apache Reservation

USGS Publications Warehouse

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

Asynchronous Amazon forest canopy phenology indicates adaptation to both water and light availability

NASA Astrophysics Data System (ADS)

Jones, Matthew O.; Kimball, John S.; Nemani, Ramakrishna R.

2014-12-01

Amazon forests represent nearly half of all tropical vegetation biomass and, through photosynthesis and respiration, annually process more than twice the amount of estimated carbon (CO2) from fossil fuel emissions. Yet the seasonality of Amazon canopy cover, and the extent to which seasonal fluctuations in water availability and photosynthetically available radiation influence these processes, is still poorly understood. Implementing six remotely sensed data sets spanning nine years (2003-2011), with reported field and flux tower data, we show that southern equatorial Amazon forests exhibit a distinctive seasonal signal. Seasonal timing of water availability, canopy biomass growth and net leaf flush are asynchronous in regions with short dry seasons and become more synchronous across a west-to-east longitudinal moisture gradient of increasing dry season. Forest cover is responsive to seasonal disparities in both water and solar radiation availability, temporally adjusting net leaf flush to maximize use of these generally abundant resources, while reducing drought susceptibility. An accurate characterization of this asynchronous behavior allows for improved understanding of canopy phenology across contiguous tropical forests and their sensitivity to climate variability and drought.

77 FR 20020 - Clean Water Act Section 303(d): Availability of List Decisions

Federal Register 2010, 2011, 2012, 2013, 2014

2012-04-03

... ENVIRONMENTAL PROTECTION AGENCY [FRL-9655-2] Clean Water Act Section 303(d): Availability of List Decisions AGENCY: Environmental Protection Agency. ACTION: Notice of availability. SUMMARY: This notice announces the availability of EPA's Responsiveness Summary Concerning EPA's November 30, 2011, Public Notice...

The effect of water contamination and host-related factors on ectoparasite load in an insectivorous bat.

PubMed

Korine, Carmi; Pilosof, Shai; Gross, Amit; Morales-Malacara, Juan B; Krasnov, Boris R

2017-09-01

We examined the effects of sex, age, and reproductive state of the insectivorous bat Pipistrellus kuhlii on the abundance and prevalence of arthropod ectoparasites (Macronyssidae and Cimicidae) in habitats with either sewage-polluted or natural bodies of water, in the Negev Desert, Israel. We chose water pollution as an environmental factor because of the importance of water availability in desert environments, particularly for P. kuhlii, which needs to drink on a daily basis. We predicted that parasite infestation rates would be affected by both environment and demographic cohort of the host. We found that female bats in the polluted site harbored significantly more mites than female bats in the natural site and that juveniles in the polluted site harbored significantly more cimicid individuals than juveniles in the natural site. We further found that age and sex (host-related factors) affected ectoparasite prevalence and intensity (i.e., the abundance of parasites) in the polluted site. Our results may suggest that the interaction between host-related and environment-related factors affected parasite infestations, with females and young bats being more susceptible to ectoparasites when foraging over polluted water. This effect may be particularly important for bats that must drink or forage above water for other wildlife that depend on drinking water for survival.

Drought Assessment over the Four Major River Basins of India using GRACE-based estimates of Water Availability

NASA Astrophysics Data System (ADS)

Sinha, D.; Syed, T. H.

2017-12-01

Drought is a natural disaster that has mutilating consequences over agriculture, ecosystems, economy and the society. Over the past few decades, drought related catastrophe, associated with global climate change, has escalated all across the world. Identification and analysis of drought utilizing individual hydrologic variables may be inadequate owing to the multitude of factors that are associated with the phenomenon. Therefore it is crucial to develop techniques that warrant comprehensive monitoring and assessment of droughts. In this study we propose a novel drought index (Water Availability Index (WAI)) that comprehends all the aspects of meteorologic, agricultural and hydrologic droughts. The proposed framework underscores the conceptualization and utilization of water availability, quantified as an integrated estimate of land water storage, using Gravity Recovery and Climate Experiment (GRACE) observations, and precipitation. The methodology is employed over four major river basins of India (i.e. Ganga, Krishna, Godavari and Mahanadi) for a period of 155 months (April 2002 to February 2015). Results exhibit the potential of the propounded index (WAI) to recognize drought events and impart insightful quantification of drought severity. WAI also demonstrates enhanced outcomes in comparison to other commonly used drought indices like PDSI, SPI, SPEI and SRI. In general there are at least three major drought periods with intensities ranging from moderate to severe in almost all river basins. The longest drought period, extending for 27 months, from September 2008 to November 2010, is observed in the Mahanadi basin. Results from this study confirm the potential of this technique as an effective tool for the characterization of drought at large spatial scales, which will only excel with better quantification and extended availability of terrestrial water storage observations from the GRACE-Follow On mission.

Determining the impacts of climate change and catchment development on future water availability in Tasmania, Australia

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

A model for evaluating effects of climate, water availability, and water management on wetland impoundments--a case study on Bowdoin, Long Lake, and Sand Lake National Wildlife Refuges

USGS Publications Warehouse

Tangen, Brian A.; Gleason, Robert A.; Stamm, John F.

2013-01-01

Many wetland impoundments managed by the U.S. Fish and Wildlife Service (USFWS) National Wildlife Refuge System throughout the northern Great Plains rely on rivers as a primary water source. A large number of these impoundments currently are being stressed from changes in water supplies and quality, and these problems are forecast to worsen because of projected changes to climate and land use. For example, many managed wetlands in arid regions have become degraded owing to the long-term accumulation of salts and increased salinity associated with evapotranspiration. A primary goal of the USFWS is to provide aquatic habitats for a diversity of waterbirds; thus, wetland managers would benefit from a tool that facilitates evaluation of wetland habitat quality in response to current and anticipated impacts of altered hydrology and salt balances caused by factors such as climate change, water availability, and management actions. A spreadsheet model that simulates the overall water and salinity balance (WSB model) of managed wetland impoundments is presented. The WSB model depicts various habitat metrics, such as water depth, salinity, and surface areas (inundated, dry), which can be used to evaluate alternative management actions under various water-availability and climate scenarios. The WSB model uses widely available spreadsheet software, is relatively simple to use, relies on widely available inputs, and is readily adaptable to specific locations. The WSB model was validated using data from three National Wildlife Refuges with direct and indirect connections to water resources associated with rivers, and common data limitations are highlighted. The WSB model also was used to conduct simulations based on hypothetical climate and management scenarios to demonstrate the utility of the model for evaluating alternative management strategies and climate futures. The WSB model worked well across a range of National Wildlife Refuges and could be a valuable tool for USFWS

Inoculating chlamydospores of Trichoderma asperellum SM-12F1 changes arsenic availability and enzyme activity in soils and improves water spinach growth.

PubMed

Su, Shiming; Zeng, Xibai; Bai, Lingyu; Williams, Paul N; Wang, Yanan; Zhang, Lili; Wu, Cuixia

2017-05-01

Arsenic (As)-contaminated agricultural soils threaten crop yields and pose a human health risk. Augmentation of exogenous microorganisms exhibiting plant-growth promoting and As speciation changing shows potential to improve crop growth and change soil As availability. Trichoderma asperellum SM-12F1 exhibiting both traits was developed into chlamydospores to improve its persistence in contaminated soils. After inoculation, As availability and enzyme activity in two types of soils and the growth as well as As uptake of water spinach (Ipomoea aquatic Forsk.) were investigated. The results indicated that inoculation significantly improved water spinach growth in both soils. Inoculating chlamydospores at 5% significantly increased As concentration (139%), bioconcentration factor (150%), and translocation factor (150%) in water spinach grown in Chenzhou (CZ) soils, while no significant change for these in Shimen (SM) soils. Inoculating chlamydospores at 5% caused a significant increase (16%) of available As content in CZ soils, while a significant decrease (13%) in SM soils. Inoculation significantly caused As methylation in both soils, while significant As reduction merely observed in CZ soils. The differential changes in available As contents in both soils were attributed to the soil pH, As fractionations and speciation characteristics. Furthermore, Inoculating chlamydospores at 5% significantly improved the activities of β-glucosidase (155%), chitinase (211%), and phosphatase (108%) in SM soils, while significant decreases in β-glucosidase (81%), phosphatase (54%), aminopeptidase (60%), and catalase (67%) in CZ soils. Bioaugmentation and As availability change were responsible for this result. These observations will be helpful for the application of fungal chlamydospores in the future bioremediation. Copyright © 2017. Published by Elsevier Ltd.

Water availability at hospitals in low- and middle-income countries: implications for improving access to safe surgical care.

PubMed

Chawla, Sagar S; Gupta, Shailvi; Onchiri, Frankline M; Habermann, Elizabeth B; Kushner, Adam L; Stewart, Barclay T

2016-09-01

Although two billion people now have access to clean water, many hospitals in low- and middle-income countries (LMICs) do not. Lack of water availability at hospitals hinders safe surgical care. We aimed to review the surgical capacity literature and document the availability of water at health facilities and develop a predictive model of water availability at health facilities globally to inform targeted capacity improvements. Using Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, a systematic search for surgical capacity assessments in LMICs in MEDLINE, PubMed, and World Health Organization Global Health Library was performed. Data regarding water availability were extracted. Data from these assessments and national indicator data from the World Bank (e.g., gross domestic product, total health expenditure, and percent of population with improved access to water) were used to create a predictive model for water availability in LMICs globally. Of the 72 records identified, 19 reported water availability representing 430 hospitals. A total of 66% of hospitals assessed had water availability (283 of 430 hospitals). Using these data, estimated percent of water availability in LMICs more broadly ranged from under 20% (Liberia) to over 90% (Bangladesh, Ghana). Less than two-thirds of hospitals providing surgical care in 19 LMICs had a reliable water source. Governments and nongovernmental organizations should increase efforts to improve water infrastructure at hospitals, which might aid in the provision of safe essential surgical care. Future research is needed to measure the effect of water availability on surgical care and patient outcomes. Copyright © 2016 Elsevier Inc. All rights reserved.

Polder Effects on Sediment-to-Soil Conversion: Water Table, Residual Available Water Capacity, and Salt Stress Interdependence

PubMed Central

Radimy, Raymond Tojo; Dudoignon, Patrick; Hillaireau, Jean Michel; Deboute, Elise

2013-01-01

The French Atlantic marshlands, reclaimed since the Middle Age, have been successively used for extensive grazing and more recently for cereal cultivation from 1970. The soils have acquired specific properties which have been induced by the successive reclaiming and drainage works and by the response of the clay dominant primary sediments, that is, structure, moisture, and salinity profiles. Based on the whole survey of the Marais Poitevin and Marais de Rochefort and in order to explain the mechanisms of marsh soil behavior, the work focuses on two typical spots: an undrained grassland since at least 1964 and a drained cereal cultivated field. The structure-hydromechanical profiles relationships have been established thanks to the clay matrix shrinkage curve. They are confronted to the hydraulic functioning including the fresh-to-salt water transfers and to the recording of tensiometer profiles. The CE1/5 profiles supply the water geochemical and geophysical data by their better accuracy. Associated to the available water capacity calculation they allow the representation of the parallel evolution of the residual available water capacity profiles and salinity profiles according to the plant growing and rooting from the mesophile systems of grassland to the hygrophile systems of drained fields. PMID:23990758

Water and nitrogen availability co-control ecosystem CO2 exchange in a semiarid temperate steppe.

PubMed

Zhang, Xiaolin; Tan, Yulian; Li, Ang; Ren, Tingting; Chen, Shiping; Wang, Lixin; Huang, Jianhui

2015-10-23

Both water and nitrogen (N) availability have significant effects on ecosystem CO2 exchange (ECE), which includes net ecosystem productivity (NEP), ecosystem respiration (ER) and gross ecosystem photosynthesis (GEP). How water and N availability influence ECE in arid and semiarid grasslands is still uncertain. A manipulative experiment with additions of rainfall, snow and N was conducted to test their effects on ECE in a semiarid temperate steppe of northern China for three consecutive years with contrasting natural precipitation. ECE increased with annual precipitation but approached peak values at different precipitation amount. Water addition, especially summer water addition, had significantly positive effects on ECE in years when the natural precipitation was normal or below normal, but showed trivial effect on GEP when the natural precipitation was above normal as effects on ER and NEP offset one another. Nitrogen addition exerted non-significant or negative effects on ECE when precipitation was low but switched to a positive effect when precipitation was high, indicating N effect triggered by water availability. Our results indicate that both water and N availability control ECE and the effects of future precipitation changes and increasing N deposition will depend on how they can change collaboratively in this semiarid steppe ecosystem.

Do shallow soil, low water availability, or their combination increase the competition between grasses with different root systems in karst soil?

PubMed

Zhao, Yajie; Li, Zhou; Zhang, Jing; Song, Haiyan; Liang, Qianhui; Tao, Jianping; Cornelissen, Johannes H C; Liu, Jinchun

2017-04-01

Uneven soil depth and low water availability are the key limiting factors to vegetation restoration and reconstruction in limestone soils such as in vulnerable karst regions. Belowground competition will possibly increase under limited soil resources. Here, we investigate whether low resource availability (including shallow soil, low water availability, and shallow soil and low water availability combined) stimulates the competition between grasses with different root systems in karst soil, by assessing their growth response, biomass allocation, and morphological plasticity. In a full three-way factorial blocked design of soil depth by water availability by neighbor identity, we grew Festuca arundinacea (deep-rooted) and Lolium perenne (shallow-rooted) under normal versus shallow soil depth, high versus low water availability, and in monoculture (conspecific neighbor) versus mixture (neighbor of the other species). The key results were as follows: (1) total biomass and aboveground biomass in either of the species decreased with reduction of resources but were not affected by planting patterns (monoculture or mixture) even at low resource levels. (2) For F. arundinacea, root biomass, root mass fraction, total root length, and root volume were higher in mixture than in monoculture at high resource level (consistent with resource use complementarity), but lower in mixture than in monoculture at low resource levels (consistent with interspecific competition). In contrast for L. perenne, either at high or low resource level, these root traits had mostly similar values at both planting patterns. These results suggest that deep-rooted and shallow-rooted plant species can coexist in karst regions under current climatic regimes. Declining resources, due to shallow soil, a decrease in precipitation, or combined shallow soil and karst drought, increased the root competition between plants of deep-rooted and shallow-rooted species. The root systems of deep-rooted plants may be

Global pattern of trends in streamflow and water availability in a changing climate.

PubMed

Milly, P C D; Dunne, K A; Vecchia, A V

2005-11-17

Water availability on the continents is important for human health, economic activity, ecosystem function and geophysical processes. Because the saturation vapour pressure of water in air is highly sensitive to temperature, perturbations in the global water cycle are expected to accompany climate warming. Regional patterns of warming-induced changes in surface hydroclimate are complex and less certain than those in temperature, however, with both regional increases and decreases expected in precipitation and runoff. Here we show that an ensemble of 12 climate models exhibits qualitative and statistically significant skill in simulating observed regional patterns of twentieth-century multidecadal changes in streamflow. These models project 10-40% increases in runoff in eastern equatorial Africa, the La Plata basin and high-latitude North America and Eurasia, and 10-30% decreases in runoff in southern Africa, southern Europe, the Middle East and mid-latitude western North America by the year 2050. Such changes in sustainable water availability would have considerable regional-scale consequences for economies as well as ecosystems.

Hydrologic modeling for monitoring water availability in Africa and the Middle East

NASA Astrophysics Data System (ADS)

McNally, A.; Getirana, A.; Arsenault, K. R.; Peters-Lidard, C. D.; Verdin, J. P.

2015-12-01

Drought impacts water resources required by crops and communities, in turn threatening lives and livelihoods. Early warning systems, which rely on inputs from hydro-climate models, are used to help manage risk and provide humanitarian assistance to the right place at the right time. However, translating advancements in hydro-climate science into action is a persistent and time-consuming challenge: scientists and decision-makers need to work together to enhance the salience, credibility, and legitimacy of the hydrological data products being produced. One organization that tackles this challenge is the Famine Early Warning Systems Network (FEWS NET), which has been using evidence-based approaches to address food security since the 1980s.In this presentation, we describe the FEWS NET Land Data Assimilation System (FLDAS), developed by FEWS NET and NASA hydrologic scientists to maximize the use of limited hydro-climatic observations for humanitarian applications. The FLDAS, an instance of the NASA Land Information System (LIS), is comprised of land surface models driven by satellite rainfall inputs already familiar to FEWS NET food security analysts. First, we evaluate the quality of model outputs over parts of the Middle East and Africa using remotely sensed soil moisture and vegetation indices. We then describe derived water availability indices that have been identified by analysts as potentially useful sources of information. Specifically, we demonstrate how the Baseline Water Stress and Drought Severity Index detect recent water availability crisis events in the Tigris-Euphrates Basin and the Gaborone Reservoir, Botswana. Finally we discuss ongoing work to deliver this information to FEWS NET analysts in a timely and user-friendly manner, with the ultimate goal of integrating these water availability metrics into regular decision-making activities.

Screening of hormone-like activities in bottled waters available in Southern Spain using receptor-specific bioassays.

PubMed

Real, Macarena; Molina-Molina, José-Manuel; Jiménez-Díaz, Inmaculada; Arrebola, Juan Pedro; Sáenz, José-María; Fernández, Mariana F; Olea, Nicolás

2015-01-01

Bottled water consumption is a putative source of human exposure to endocrine-disrupting chemicals (EDCs). Research has been conducted on the presence of chemicals with estrogen-like activity in bottled waters and on their estrogenicity, but few data are available on the presence of hormonal activities associated with other nuclear receptors (NRs). The aim of this study was to determine the presence of endocrine activities dependent on the activation of human estrogen receptor alpha (hERa) and/or androgen receptor (hAR) in water in glass or plastic bottles sold to consumers in Southern Spain. Hormone-like activities were evaluated in 29 bottled waters using receptor-specific bioassays based on reporter gene expression in PALM cells [(anti-)androgenicity] and cell proliferation assessment in MCF-7 cells [(anti-)estrogenicity] after optimized solid phase extraction (SPE). All of the water samples analyzed showed hormonal activity. This was estrogenic in 79.3% and anti-estrogenic in 37.9% of samples and was androgenic in 27.5% and anti-androgenic in 41.3%, with mean concentrations per liter of 0.113pM 17β-estradiol (E2) equivalent units (E2Eq), 11.01pM anti-estrogen (ICI 182780) equivalent units (ICI 182780Eq), 0.33pM methyltrienolone (R1881) equivalent units (R1881Eq), and 0.18nM procymidone equivalent units (ProcEq). Bottled water consumption contributes to EDC exposure. Hormone-like activities observed in waters from both plastic and glass bottles suggest that plastic packaging is not the sole source of contamination and that the source of the water and bottling process may play a role, among other factors. Further research is warranted on the cumulative effects of long-term exposure to low doses of EDCs. Copyright © 2014 Elsevier Ltd. All rights reserved.

Estimated water use and availability in the East Narragansett Bay study area, Rhode Island, 1995-99

USGS Publications Warehouse

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

Factors affecting ground-water exchange and catchment size for Florida lakes in mantled karst terrain

USGS Publications Warehouse

Lee, Terrie Mackin

2002-01-01

In the mantled karst terrain of Florida, the size of the catchment delivering ground-water inflow to lakes is often considerably smaller than the topographically defined drainage basin. The size is determined by a balance of factors that act individually to enhance or diminish the hydraulic connection between the lake and the adjacent surficial aquifer, as well as the hydraulic connection between the surficial aquifer and the deeper limestone aquifer. Factors affecting ground-water exchange and the size of the ground-water catchment for lakes in mantled karst terrain were examined by: (1) reviewing the physical and hydrogeological characteristics of 14 Florida lake basins with available ground-water inflow estimates, and (2) simulating ground-water flow in hypothetical lake basins. Variably-saturated flow modeling was used to simulate a range of physical and hydrogeologic factors observed at the 14 lake basins. These factors included: recharge rate to the surficial aquifer, thickness of the unsaturated zone, size of the topographically defined basin, depth of the lake, thickness of the surficial aquifer, hydraulic conductivity of the geologic units, the location and size of karst subsidence features beneath and onshore of the lake, and the head in the Upper Floridan aquifer. Catchment size and the magnitude of ground-water inflow increased with increases in recharge rate to the surficial aquifer, the size of the topographically defined basin, hydraulic conductivity in the surficial aquifer, the degree of confinement of the deeper Upper Floridan aquifer, and the head in the Upper Floridan aquifer. The catchment size and magnitude of ground-water inflow increased with decreases in the number and size of karst subsidence features in the basin, and the thickness of the unsaturated zone near the lake. Model results, although qualitative, provided insights into: (1) the types of lake basins in mantled karst terrain that have the potential to generate small and large

Recharging California's Groundwater: Crop Suitability and Surface Water Availability for Agricultural Groundwater Banking

NASA Astrophysics Data System (ADS)

Dahlke, H. E.; Kocis, T. N.; Brown, A.

2016-12-01

Groundwater banking, the intentional recharge of groundwater from surface water for storage and recovery, is an important conjunctive use strategy for water management in California (CA). A largely unexplored approach to groundwater banking, agricultural groundwater banking (ag-GB), utilizes flood flows and agricultural lands (alfalfa/pasture) for recharging groundwater. Understanding soil suitability for ag-GB, crop health and flooding tolerance, leaching of soil nitrate and salts, the availability of surface water for recharge, and the economic costs and benefits of ag-GB is fundamental to assessing the feasibility of local-scale implementation of ag-GB. The study presented here considers both the availability of excess streamflow (e.g., the magnitude, frequency, timing, and duration of winter flood flow) for ag-GB and the risks and benefits associated with using alfalfa fields as spreading grounds for ag-GB. The availability of surface water for winter (Nov to Apr) ag-GB were estimated based on daily streamflow records for 93 stream gauges within the Central Valley, CA. Analysis focused on high-magnitude (>90thpercentile) flows because most lower flows are likely legally allocated in CA. Results based >50 years of data indicate that an average winter/spring (Nov. - Apr.) in the Sacramento River Basin could provide 7 million acre-feet (AF) (8.6 km3) of water for ag-GB from flows above the 90th percentile. These flows originate from few storm events (5-7 events) and occur on average for 25-30 days between November and April. Wintertime on-farm recharge experiments were conducted on a 9-yr old, 15-acre alfalfa field in the Scott Valley, CA, where 135 AF and 107 AF of water were recharged during the winters of 2015 and 2016, respectively. Biomass data collected indicates that pulsed application of 6-10 ft of water on dormant alfalfa results in minimal yield loss (0.5 ton/acre reduction), short-duration saturated conditions in the root-zone, and high recharge

Availability of safe drinking-water: the answer to cholera outbreak? Nabua, Camarines Sur, Philippines, 2012.

PubMed

De Guzman, Alethea; de los Reyes, Vikki Carr; Sucaldito, Ma Nemia; Tayag, Enrique

2015-01-01

In May 2012, there were increasing diarrhoea cases and deaths reported from Nabua, Camarines Sur to the Philippines event-based surveillance system. An investigation was conducted to identify risk factors and determine transmission dynamics. A suspected case was defined as a resident of Nabua with at least three episodes of watery diarrhoea per day from 16 March to 22 June 2012. A confirmed case was defined as a suspected case positive for Vibrio cholerae. An environmental investigation was conducted and rectal swabs and water samples sent to the national reference laboratory for bacterial isolation. A 1:2 case-control study matching for age and sex was conducted. Data were analysed using Epi Info. There were 309 suspected cases with two deaths, and the most affected age group was children under five years (45%). Eight cases were positive for Vibrio cholerae Ogawa El Tor and one for Non-01. Water samples were positive for faecal coliforms and Aeromonas caviae. The case-control study showed that cases had a higher odds than controls of using unchlorinated water sources (odds ratio [OR] = 3.6; 95% confidence interval [CI]:1.6-8.5) and having toilets located within 20 m of a septic tank (OR = 2.7; 95% CI: 1.4-5.3). In multivariate analysis, the only significant factor was drinking from piped water (OR = 0.21; 95% CI: 0.09-0.49). In this cholera outbreak, drinking-water from unchlorinated wells was a significant risk factor. Future cholera control efforts should include not just improving water and sanitation systems but also intensified behaviour change campaigns.

Water availability in +2°C and +4°C worlds.

PubMed

Fung, Fai; Lopez, Ana; New, Mark

2011-01-13

While the parties to the UNFCCC agreed in the December 2009 Copenhagen Accord that a 2°C global warming over pre-industrial levels should be avoided, current commitments on greenhouse gas emissions reductions from these same parties will lead to a 50 : 50 chance of warming greater than 3.5°C. Here, we evaluate the differences in impacts and adaptation issues for water resources in worlds corresponding to the policy objective (+2°C) and possible reality (+4°C). We simulate the differences in impacts on surface run-off and water resource availability using a global hydrological model driven by ensembles of climate models with global temperature increases of 2°C and 4°C. We combine these with UN-based population growth scenarios to explore the relative importance of population change and climate change for water availability. We find that the projected changes in global surface run-off from the ensemble show an increase in spatial coherence and magnitude for a +4°C world compared with a +2°C one. In a +2°C world, population growth in most large river basins tends to override climate change as a driver of water stress, while in a +4°C world, climate change becomes more dominant, even compensating for population effects where climate change increases run-off. However, in some basins where climate change has positive effects, the seasonality of surface run-off becomes increasingly amplified in a +4°C climate.

Mapping water availability, cost and projected consumptive use in the eastern United States with comparisons to the west

NASA Astrophysics Data System (ADS)

Tidwell, Vincent C.; Moreland, Barbie D.; Shaneyfelt, Calvin R.; Kobos, Peter

2018-01-01

The availability of freshwater supplies to meet future demand is a growing concern. Water availability metrics are needed to inform future water development decisions. With the help of water managers, water availability was mapped for over 1300 watersheds throughout the 31 contiguous states in the eastern US complimenting a prior study of the west. The compiled set of water availability data is unique in that it considers multiple sources of water (fresh surface and groundwater, wastewater and brackish groundwater); accommodates institutional controls placed on water use; is accompanied by cost estimates to access, treat and convey each unique source of water; and is compared to projected future growth in consumptive water use to 2030. Although few administrative limits have been set on water availability in the east, water managers have identified 315 fresh surface water and 398 fresh groundwater basins (with 151 overlapping basins) as areas of concern (AOCs) where water supply challenges exist due to drought related concerns, environmental flows, groundwater overdraft, or salt water intrusion. This highlights a difference in management where AOCs are identified in the east which simply require additional permitting, while in the west strict administrative limits are established. Although the east is generally considered ‘water rich’ roughly a quarter of the basins were identified as AOCs; however, this is still in strong contrast to the west where 78% of the surface water basins are operating at or near their administrative limit. Little effort was noted on the part of eastern or western water managers to quantify non-fresh water resources.

Water use and availability in the West Narragansett Bay area, coastal Rhode Island, 1995-99

USGS Publications Warehouse

Nimiroski, Mark T.; Wild, Emily C.

2006-01-01

During the 1999 drought in Rhode Island, belowaverage precipitation caused a drop in ground-water levels and streamflow was below long-term averages. The low water levels prompted the U. S. Geological Survey and the Rhode Island Water Resources Board to conduct a series of cooperative water-use studies. The purpose of these studies is to collect and analyze water-use and water-availability data in each drainage area in the State of Rhode Island. The West Narragansett Bay study area, which covers 118 square miles in part or all of 14 towns in coastal Rhode Island, is one of nine areas investigated as part of this effort. The study area includes the western part of Narragansett Bay and Conanicut Island, which is the town of Jamestown. The area was divided into six subbasins for the assessment of water-use data. In the calculation of hydrologic budget and water availability, the Hunt, Annaquatucket, and Pettaquamscutt River Basins were combined into one subbasin because they are hydraulically connected. Eleven major water suppliers served customers in the study area, and they supplied an average of 19.301 million gallons per day during 1995–99. The withdrawals from the only minor supplier, which was in the town of East Greenwich in the Hunt River Basin, averaged 0.002 million gallons per day. The remaining withdrawals were estimated as 1.186 million gallons per day from self-supplied domestic, commercial, industrial, and agricultural users. Return flows from self-disposed water (individual sewage-disposal systems) and permitted discharges accounted for 5.623 million gallons per day. Most publicly disposed water (13.711 million gallons per day) was collected by the Rhode Island Economic Development Corporation, and by the East Greenwich, Fields Point, Jamestown, Narragansett, and Scarborough wastewater-treatment facilities. This wastewater was disposed in Narragansett Bay outside of the study area. The PART program, a computerized hydrograph-separation application

Soil water availability and rooting depth as determinants of hydraulic architecture of Patagonian woody species

Treesearch

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...

Competing effects of groundwater withdrawals and climate change on water availability in semi-arid India

NASA Astrophysics Data System (ADS)

Sishodia, R. P.; Shukla, S.

2017-12-01

India, a global leader in groundwater use (250 km3/yr), is experiencing groundwater depletion. There has been a 130-fold increase in number of irrigation wells since 1960. Anticipated future increase in groundwater demand is likely to exacerbate the water availability in the semi-arid regions of India. Depending on the direction of change, future climate change may either worsen or enhance the water availability. This study uses an integrated hydrologic modeling approach (MIKE SHE MIKE 11) to compare and combine the effects of future (2040-2069) increased groundwater withdrawals and climate change on surface and groundwater flows and availability for an agricultural watershed in semi-arid south India. Modeling results showed that increased groundwater withdrawals in the future resulted in reduced surface flows (25%) and increased frequency and duration (90 days/yr) of well drying. In contrast, projected future increase in rainfall (7-43%) under the changed climate showed increased groundwater recharge (15-67%) and surface flows (9-155%). Modeling results suggest that the positive effects of climate change may enhance the water availability in this semi-arid region of India. However, in combination with increased withdrawals, climate change was shown to increase the well drying and reduce the water availability especially during dry years. A combination of management options such as flood to drip conversion, energy subsidy reductions and water storage can support increased groundwater irrigated area in the future while mitigating the well drying. A cost-benefit analysis showed that dispersed water storage and flood to drip conversion can be highly cost-effective in this semi-arid region. The study results suggest that the government and management policies need to be focused towards an integrated management of demand and supply to create a sustainable food-water-energy nexus in the region.

[Temporal variation of water quality and driving factors in Yanghe watershed of Zhangjiakou].

PubMed

Pang, Bo; Wang, Tie-Yu; Lü, Yong-Long; Du, Li-Yu; Luo, Wei

2013-01-01

Yanghe is an important water source for Guanting Reservoir, which once supplied the Beijing city with drinking water, industrial process water and water-use in landscape. Based on the data of water quality monitored by Yanghe watershed monitoring stations from 1992 to 2009, 11 pollutants were selected for analysis. The trends of changes in water quality were figured out, and the major pollutants and driving factors were measured by the integrated standard index and grey correlation analytical methods. The results showed that there were two stages of water quality change in Yanghe watershed of Zhangjiakou. Firstly, the water was polluted seriously but recovered rapidly from 1992 to 1996. Secondly, although light pollution occurred in the watershed from 1997 to 2009, the pollution factors were still above the limits. The main pollution factors are ammonia nitrogen, petroleum, permanganate index, BOD5, Cr6+ and Cd. The main driving factor of water quality is the change of land use type, and the agricultural land showed less impact on water quality than the industrial land.

Influence of water availability in the distributions of branched glycerol dialkyl glycerol tetraether in soils of the Iberian Peninsula

NASA Astrophysics Data System (ADS)

Menges, J.; Huguet, C.; Alcañiz, J. M.; Fietz, S.; Sachse, D.; Rosell-Melé, A.

2014-05-01

The combined application of the MBT (degree of methylation) and CBT (degree of cyclization) indices, based on the distribution of branched glycerol dialkyl glycerol tetraethers (brGDGTs) in soils, has been proposed as a paleoproxy to estimate mean annual temperature (MAT). CBT quantifies the degree of cyclization of brGDGTs and relates to soil pH. MBT and the simplified version MBT' quantify the degree of methylation of brGDGTs and relate to MAT and soil pH. However, other factors such as soil water availability have also been suggested to influence MBT' and possibly restrict the combined application of the MBT' and CBT indices as a paleotemperature proxy. To assess the effect of hydrological conditions on MBT' and CBT, a set of 23 Iberian Peninsula soil samples, covering a MAT range from 10 to 18 °C and a mean annual precipitation (MAP) range of 405 mm to 1455 mm, was analyzed. We found that the CBT was indeed significantly correlated with soil pH in our sample set. In contrast, MBT' was not correlated with MAT but had a significant correlation with the aridity index (AI), a parameter related to water availability in soils. The AI can explain 50% of the variation of the MBT', and 70% of the residuals of MAT estimated with the MBT/CBT proxy as compared to instrumentally measured MAT. We propose that, in arid settings, where water may be an ecologically limiting factor, MBT' is influenced by hydrological conditions rather than temperature. Thus, our results suggest that the combination of MBT' and CBT indices should be applied with caution in paleotemperature reconstructions in soils from dry subhumid to hyperarid environments.

Global pattern of trends in streamflow and water availability in a changing climate

USGS Publications Warehouse

Milly, P.C.D.; Dunne, K.A.; Vecchia, A.V.

2005-01-01

Water availability on the continents is important for human health, economic activity, ecosystem function and geophysical processes. Because the saturation vapour pressure of water in air is highly sensitive to temperature, perturbations in the global water cycle are expected to accompany climate warming. Regional patterns of warming-induced changes in surface hydroclimate are complex and less certain than those in temperature, however, with both regional increases and decreases expected in precipitation and runoff. Here we show that an ensemble of 12 climate models exhibits qualitative and statistically significant skill in simulating observed regional patterns of twentieth-century multidecadal changes in streamflow. These models project 10–40% increases in runoff in eastern equatorial Africa, the La Plata basin and high-latitude North America and Eurasia, and 10–30% decreases in runoff in southern Africa, southern Europe, the Middle East and mid-latitude western North America by the year 2050. Such changes in sustainable water availability would have considerable regional-scale consequences for economies as well as ecosystems.

Critical factors for achieving multiple goals with water tariff systems: Combining limited data sources and expert testimony

NASA Astrophysics Data System (ADS)

Dalhuisen, Jasper; Nijkamp, Peter

2002-07-01

Price instruments are well-known policy handles to influence effectively residential water demand. Prices used to be set by water authorities in such a way that the principle of cost coverage was respected; they acted as prominent instruments in residential water policies in the past decades. More recently, however, price instruments are increasingly used to meet simultaneously financial, environmental, and social goals. This paper addresses four conditions for an appropriate tariff system for residential water use which are often found in the recent literature on the economics of water use. The paper analyzes the importance of background factors (e.g., low water availability) of these four principles as well as the extent to which actual tariff systems are employed in five mutually contrasting cities (Amsterdam, Athens, London, Seville, and Tel Aviv). Meta-analytic techniques, in particular, rough set analysis stemming from artificial intelligence, are applied to identify the common underlying relations between background factors and success of achieving multiple goals in these five urban case studies. The paper concludes with policy recommendations.

The Great Lakes Water Balance: Data availability and annotated bibliography of selected references

USGS Publications Warehouse

Neff, Brian P.; Killian, Jason R.

2003-01-01

Water balance calculations for the Great Lakes have been made for several decades and are a key component of Great Lakes water management. Despite the importance of the water balance, little has been done to inventory and describe the data available for use in water balance calculations. This report provides a catalog and brief description of major datasets that are used to calculate the Great Lakes water balance. Several additional datasets are identified that could be used to calculate parts of the water balance but currently are not being used. Individual offices and web pages that are useful for attaining these datasets are included. Four specific data gaps are also identified. An annotated bibliography of important publications dealing with the Great Lakes water balance is included. The findings of this investigation permit resource managers and scientists to access data more easily, assess shortcomings of current datasets, and identify which data are not currently being utilized in water balance calculations.

Water on Mars: Volatile history and resource availability

NASA Technical Reports Server (NTRS)

Jakosky, Bruce M.

1991-01-01

The existence of water on Mars is undisputed today. Measurements of atmospheric water vapor have shown that the abundance varies with location and season in a systematic way which depends on processes of exchange with the polar caps, regolith, and atmosphere. Channels, which give the appearance of having been carved by water or of having had water involved in their formation, appear in various locations on the surface; some were formed by catastrophic outflow of water from beneath the surface, while others form valley networks which give the appearance of having formed over long periods of time primarily early in the planet's history. The north polar residual cap consists of water ice, possibly containing an amount of water equivalent to a global layer several tens of meters thick. Finally, water is observed within the regolith, as adsorbed water or as water of hydration.

Dynamic factor analysis for estimating ground water arsenic trends.

PubMed

Kuo, Yi-Ming; Chang, Fi-John

2010-01-01

Drinking ground water containing high arsenic (As) concentrations has been associated with blackfoot disease and the occurrence of cancer along the southwestern coast of Taiwan. As a result, 28 ground water observation wells were installed to monitor the ground water quality in this area. Dynamic factor analysis (DFA) is used to identify common trends that represent unexplained variability in ground water As concentrations of decommissioned wells and to investigate whether explanatory variables (total organic carbon [TOC], As, alkalinity, ground water elevation, and rainfall) affect the temporal variation in ground water As concentration. The results of the DFA show that rainfall dilutes As concentration in areas under aquacultural and agricultural use. Different combinations of geochemical variables (As, alkalinity, and TOC) of nearby monitoring wells affected the As concentrations of the most decommissioned wells. Model performance was acceptable for 11 wells (coefficient of efficiency >0.50), which represents 52% (11/21) of the decommissioned wells. Based on DFA results, we infer that surface water recharge may be effective for diluting the As concentration, especially in the areas that are relatively far from the coastline. We demonstrate that DFA can effectively identify the important factors and common effects representing unexplained variability common to decommissioned wells on As variation in ground water and extrapolate information from existing monitoring wells to the nearby decommissioned wells.

Mapping water availability, cost and projected consumptive use in the Eastern United States with comparisons to the West

DOE PAGES

Tidwell, Vincent; Moreland, Barbara D.; Shaneyfelt, Calvin; ...

2017-11-08

The availability of freshwater supplies to meet future demand is a growing concern. Water availability metrics are needed to inform future water development decisions. Furthermore, with the help of water managers, water availability was mapped for over 1300 watersheds throughout the 31-contiguous states in the eastern U.S. complimenting a prior study of the west. The compiled set of water availability data is unique in that it considers multiple sources of water (fresh surface and groundwater, wastewater and brackish groundwater); accommodates institutional controls placed on water use; is accompanied by cost estimates to access, treat and convey each unique source ofmore » water, and; is compared to projected future growth in consumptive water use to 2030. Although few administrative limits have been set on water availability in the east, water managers have identified 315 fresh surface water and 398 fresh groundwater basins (with 151 overlapping basins) as Areas of Concern (AOCs) where water supply challenges exist due to drought related concerns, environmental flows, groundwater overdraft, or salt water intrusion. This highlights a difference in management where AOCs are identified in the east which simply require additional permitting, while in the west strict administrative limits are established. Although the east is generally considered "water rich" roughly a quarter of the basins were identified as AOCs; however, this is still in strong contrast to the west where 78% of the surface water basins are operating at or near their administrative limit. There was little effort noted on the part of eastern or western water managers to quantify non-fresh water resources.« less

Impacts of Change in Irrigation Water Availability on Food Production in the Yellow River Basin under Climate Change

NASA Astrophysics Data System (ADS)

Yin, Y. Y.; Tang, Q.

2014-12-01

Approximately 9 percent of China's population and 17 percent of its agricultural area are settled in the Yellow River Basins. Irrigation, which plays an important role in agricultural production, occupies the largest share of human consumptive water use in the basin. Given increasing water demands, the basin faces acute water scarcity. Previous studies have suggested that decrease in irrigation water availability under climate change might have an overall adverse impact on the food production of the basin. The timing and area that would face severe water stress are yet to be identified. We used a land surface hydrological model forced with the bias-corrected climatic variables from 5 climate models under 4 Representative Concentration Pathways (RCPs) to estimate total water availability in the sub-basins of the Yellow River basin. The future socioeconomic conditions, the Shared Socioeconomic Pathways (SSPs), were used to estimate the water requirement in the nonagricultural water use sectors. The irrigation water availability was estimated from the total water availability and nonagricultural water use, and the irrigation water demands were estimated based on the current irrigation project efficiencies. The timing and area of irrigation water shortage were shown and the implication of change in irrigation water availability on food production was assessed. The results show that the sub-basins with high population density and gross domestic product (GDP) are likely to confront severe water stress and reduction in food production earlier because irrigation water was to be appropriated by the rapid increase in nonagricultural water use sectors. The study stresses the need for adaptive management of water to balance agriculture and nonagricultural demands in northern China.

Mapping water availability, cost and projected consumptive use in the Eastern United States with comparisons to the West

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

Tidwell, Vincent; Moreland, Barbara D.; Shaneyfelt, Calvin

The availability of freshwater supplies to meet future demand is a growing concern. Water availability metrics are needed to inform future water development decisions. Furthermore, with the help of water managers, water availability was mapped for over 1300 watersheds throughout the 31-contiguous states in the eastern U.S. complimenting a prior study of the west. The compiled set of water availability data is unique in that it considers multiple sources of water (fresh surface and groundwater, wastewater and brackish groundwater); accommodates institutional controls placed on water use; is accompanied by cost estimates to access, treat and convey each unique source ofmore » water, and; is compared to projected future growth in consumptive water use to 2030. Although few administrative limits have been set on water availability in the east, water managers have identified 315 fresh surface water and 398 fresh groundwater basins (with 151 overlapping basins) as Areas of Concern (AOCs) where water supply challenges exist due to drought related concerns, environmental flows, groundwater overdraft, or salt water intrusion. This highlights a difference in management where AOCs are identified in the east which simply require additional permitting, while in the west strict administrative limits are established. Although the east is generally considered "water rich" roughly a quarter of the basins were identified as AOCs; however, this is still in strong contrast to the west where 78% of the surface water basins are operating at or near their administrative limit. There was little effort noted on the part of eastern or western water managers to quantify non-fresh water resources.« less

Characterization factors for water footprint considering the scarcity of green and blue water sources

NASA Astrophysics Data System (ADS)

Oki, T.; Kondo, T.; Pokhrel, Y. N.; Hanasaki, N.

2011-12-01

The original concept of virtual water trade was invented to illustrate how much water demand can be reduced by importing food products (Allan 1996), and expanded for meat products and industrial products (Oki and Kanae, 2004). However, there was a confusion between "virtual trade of water" (original) and "trade of virtual water" (misinterpretation but widely accepted), and "virtual water" has been recognized as how much water was used to produce the commodity. Then, the concept has some analogy to carbon footprint (CFP) which is an indicator of total emission of greenhouse gases, and nowadays called water footprint (WFP, Hoekstra, 2004). However, WFP itself is just an inventory of water usages under the framework of life cycle assessment (LCA), and the volume of WFP does not necessary reflect the environmental impacts of water usages because consumptive water use of 100 liter from ground water in arid regions just before rainy season would have more environmental impacts than consumptive water use of 100 liter from rain water in humid regions during snow melt season. In the case of CFP, the emissions of five greenhouse gases except for CO2 were converted into CO2 equivalent volumes by considering the sensitivity for the global warming potential, and summed up into CFP. Here, we propose a new idea objectively determining the weights (characterization factors) for blue water usages, such as from river and ground water, to be converted into green water equivalent in each region and time. The weights are inversely proportional to the area required to obtain the same amount of green water, and water balance model can provide the basic information. The new concept was applied to the WFP of Japan through the imports of major crops. As an inventory, WFP was 15.5 km3/y of rain water, 2.2 km3/y of river water, and 2.0 km3/y of non-renewable and non-local water (NRNL water) for year 2000, however, considering the proposed characterization factors in each region (0.5 x 0

Probabilistic Water Availability Prediction in the Rio Grande Basin using Large-scale Circulation Indices as Precursor

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

Fusion of multisource and multiscale remote sensing data for water availability assessment in a metropolitan region

NASA Astrophysics Data System (ADS)

Chang, N. B.; Yang, Y. J.; Daranpob, A.

2009-09-01

Recent extreme hydroclimatic events in the United States alone include, but are not limited to, the droughts in Maryland and the Chesapeake Bay area in 2001 through September 2002; Lake Mead in Las Vegas in 2000 through 2004; the Peace River and Lake Okeechobee in South Florida in 2006; and Lake Lanier in Atlanta, Georgia in 2007 that affected the water resources distribution in three states - Alabama, Florida and Georgia. This paper provides evidence from previous work and elaborates on the future perspectives that will collectively employ remote sensing and in-situ observations to support the implementation of the water availability assessment in a metropolitan region. Within the hydrological cycle, precipitation, soil moisture, and evapotranspiration can be monitored by using WSR-88D/NEXRAD data, RADARSAT-1 images, and GEOS images collectively to address the spatiotemporal variations of quantitative availability of waters whereas the MODIS images may be used to track down the qualitative availability of waters in terms of turbidity, Chlorophyll-a and other constitutes of concern. Tampa Bay in Florida was selected as a study site in this analysis, where the water supply infrastructure covers groundwater, desalination plant, and surface water at the same time. Research findings show that through the proper fusion of multi-source and multi-scale remote sensing data for water availability assessment in metropolitan region, a new insight of water infrastructure assessment can be gained to support sustainable planning region wide.

Impacts of Potential Changes in Land Use, Climate, and Water Use on Water Availability, Coastal Carolinas Region, Southeastern United States

NASA Astrophysics Data System (ADS)

Gurley, L. N.; Garcia, A. M.

2017-12-01

Sustainable growth in coastal areas with rapidly increasing populations, such as the coastal regions of North and South Carolina, relies on an understanding of the current state of coastal natural resources coupled with the ability to assess future impacts of changing coastal communities and resources. Changes in climate, water use, population, and land use (e.g. urbanization) will place additional stress on societal and ecological systems that are already competing for water resources. The potential effects of these stressors on water availability are not fully known. To meet societal and ecological needs, water resources management and planning efforts require estimates of likely impacts of population growth, land-use, and climate. Two Soil and Water Assessment (SWAT) hydrologic models were developed to help address the challenges that water managers face in the Carolinas: the (1) Cape Fear and (2) Pee Dee drainage basins. SWAT is a basin-scale, process-based watershed model with the capability of simulating water-management scenarios. Model areas were divided into two square mile sub-basins to evaluate ecological response at headwater streams. The sub-basins were subsequently divided into smaller, discrete hydrologic response units based on land use, slope, and soil type. Monthly and annual water-use data were used for 2000 to 2014 and included estimates of municipal, industrial, agricultural, and commercial water use. Models were calibrated for 2000 to 2014 and potential future streamflows were estimated through 2060 based on a suite of scenarios that integrated land use change projections, climate projections and water-use forecasts. The approaches and new techniques developed as part of this research could be applied to other coastal areas that face similar current and future water availability demands.

A review of limits on microbial activity in the cryosphere: temperature and water availability

NASA Astrophysics Data System (ADS)

Bakermans, C.

2017-12-01

The extent of microbial activity in the cryosphere likely depends on many things: the presence of liquid water, an adequate energy and nutrient supply (amount and flux), the absence of damaging conditions, exposure to low temperatures, and the time to evolve adaptations to low temperature conditions. Determining the extent of microbial activity in the cryosphere is a challenge complicated by the reduced availability of liquid water as water freezes and the low rates of diffusion and reaction brought on by low temperatures. Despite these limitations, many studies have demonstrated that reproduction by microorganisms is possible at temperatures of -10 to -20°C and that metabolism continues to even lower temperatures of about -30°C. In addition, microcosm studies in frozen soils and permafrost have demonstrated respiration down to temperatures of -18°C and DNA synthesis at temperatures from 0 to -20°C. In the environment, low temperature conditions (and lack of liquid water) appear to limit microbial activity in a few places like Don Juan Pond and University Valley in Antarctica. Microorganisms may be metabolically active in Arctic permafrost, but metabolism may be so exceptionally slow as to escape detection. Given the slow metabolism expected and the short geological age of permafrost (3 million years at the longest), there is probably insufficient time for microorganisms to evolve to become better adapted to live at subfreezing temperatures. Indeed, terrestrial life may never have the chance to evolve to exploit the low temperature capabilities of its biomolecules in view of the limited times at which cold environments persist on Earth. These observational studies of microorganisms in low temperature environments of the Polar regions expose how the extent of microbial activity at low temperature is entangled with other factors (perhaps inextricably); how the lack of liquid water at low temperatures appears to be the true limit on activity at low temperatures

Investigating Factors that Affect Dissolved Oxygen Concentration in Water

ERIC Educational Resources Information Center

Jantzen, Paul G.

1978-01-01

Describes activities that demonstrate the effects of factors such as wind velocity, water temperature, convection currents, intensity of light, rate of photosynthesis, atmospheric pressure, humidity, numbers of decomposers, presence of oxidizable ions, and respiration by plants and animals on the dissolved oxygen concentration in water. (MA)

Pesticides in ground water: distribution, trends, and governing factors

USGS Publications Warehouse

Barbash, Jack; Resek, Elizabeth A.

1997-01-01

A comprehensive review of published information on the distribution and behavior of pesticides and their transformation products in ground water indicates that pesticides from every chemical class have been detected in ground waters of the United States. Many of these compounds are commonly present at low concentrations in ground water beneath agricultural land. Little information is available on their occurrence beneath non-agricultural land, although the intensity of their use in such areas (on lawns, golf courses, rights of way, timberlands, etc.) is often comparable to, or greater than agricultural use. Information on pesticides in ground water is not sufficient to provide either a statistically representative view of pesticide occurrence in ground water across the United States, or an indication of long-term trends or changes in the severity or extent of this contamination over the past three decades. This is largely due to wide variations in analytical detection limits, well selection procedures, and other design features among studies conducted in different areas or at different times. Past approaches have not been well suited for distinguishing "point source" from "nonpoint source" pesticide contamination. Among the variety of natural and anthropogenic factors examined, those that appear to be most strongly associated with the intensity of pesticide contamination of ground water are the depth, construction and age of the sampled wells, the amount of recharge (by precipitation or irrigation), and the depth of tillage. Approaches commonly employed for predicting pesticide distributions in the subsurface--including computer simulations, indicator solutes (e.g., nitrate or tritium), and ground-water vulnerability assessments--generally provide unreliable predictions of pesticide occurrence in ground water. Such difficulties may arise largely from a general failure to account for the preferential transport of pesticides in the subsurface. Significant

Factors affecting water strider (Hemiptera: Gerridae) mercury concentrations in lotic systems

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

Jardine, T.D.; Kidd, K.A.; Cunjak, R.A.

2009-07-15

Water striders (Hemiptera: Gerridae) have been considered as a potential sentinel for mercury (Hg) contamination of freshwater ecosystems, yet little is known about factors that control Hg concentrations in this invertebrate. Striders were collected from 80 streams and rivers in New Brunswick, Canada, in August and September of 2004 through 2007 to assess the influence of factors such as diet, water chemistry, and proximity to point sources on Hg concentrations in this organism. Higher than average Hg concentrations were observed in the southwest and Grand Lake regions of the province, the latter being the location of a coal-fired power plantmore » that is a source of Hg (similar to 100 kg annually), with elevated Hg concentrations in the lichen Old Man's Beard (Usnea spp.) in its immediate vicinity. Across all streams, pH and total organic carbon of water were relatively weak predictors of strider Hg concentrations. Female striders that were larger in body size than males had significantly lower Hg concentrations within sites, suggestive of growth dilution. There was no relationship between percent aquatic carbon in the diet and Hg concentrations in striders. For those striders feeding solely on terrestrial carbon, Hg concentrations were higher in animals occupying a higher trophic level. Mercury concentrations were highly variable in striders collected monthly over two growing seasons, suggesting short-term changes in Hg availability. These measurements highlight the importance of considering both deposition and postdepositional processes in assessing Hg bioaccumulation in this species.« less

Role of soil sorption and microbial degradation on dissipation of mesotrione in plant-available soil water.

PubMed

Shaner, Dale; Brunk, Galen; Nissen, Scott; Westra, Phil; Chen, Wenlin

2012-01-01

Mesotrione is a carotenoid biosynthesis-inhibiting herbicide labeled for pre-emergence and postemergence weed control in corn production. Understanding the factors that influence the dissipation of mesotrione in soil and in the plant-available water (PAW) is important for the environmental fate assessment and optimal weed management practices. The present research investigated the role of soil properties and microbial activities on the interrelated sorption and degradation processes of mesotrione in four soils by direct measurements of PAW. We found that mesotrione bound to the soils time dependently, with approximately 14 d to reach equilibrium. The 24-h batch-slurry equilibrium experiments provided the sorption partition coefficient ranging from 0.26 to 3.53 L kg(-1), depending on soil organic carbon and pH. The dissipation of mesotrione in the soil-bound phase was primarily attributed to desorption to the PAW. Degradation in the PAW was rapid and primarily dependent on microbial actions, with half-degradation time (DT(50)) <3 d in all four soils tested. The rapid degradation in the PAW became rate limited by sorption as more available molecules were depleted in the soil pore water, resulting in a more slowed overall process for the total soil-water system (DT(50) <26 d). The dissipation of mesotrione in the PAW was due to microbial metabolism and time-dependent sorption to the soils. A coupled kinetics model calibrated with the data from the laboratory centrifugation technique provided an effective approach to investigate the interrelated processes of sorption and degradation in realistic soil moisture conditions. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Availability of ground water in the middle Merrimack River basin, central and southern New Hampshire

USGS Publications Warehouse

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)

Drought analysis and water resource availability using standardised precipitation evapotranspiration index

NASA Astrophysics Data System (ADS)

Hui-Mean, Foo; Yusop, Zulkifli; Yusof, Fadhilah

2018-03-01

Trend analysis for potential evapotranspiration (PET) and climatic water balance (CWB) is critical in identifying the wetness or dryness episodes with respect to the water surplus or deficit. The PET is computed based on the monthly average temperature for the entire Peninsular Malaysia using Thornthwaite parameterization. The trends and slope's magnitude for the PET and CWB were then investigated using Mann-Kendall, Spearman's rho tests and Thiel-Sen estimator. The 1-, 3-, 6- and 12-month standardised precipitation evapotranspiration index (SPEI) is applied to determine the drought episodes and the average recurrence interval are calculated based on the SPEI. The results indicate that most of the stations show an upward trend in annual and monthly PET while majority of the regions show an upward trend in annual CWB except for the Pahang state. The increasing trends detected in the CWB describe water is in excess especially during the northeast monsoons while the decreasing trends imply water insufficiency. The excess water is observed mostly in January especially in the west coast, east coast and southwest regions that suggest more water is available for crop requirement. The average recurrence interval for drought episodes is almost the same for the smaller severity with various time scale of SPEI and high probability of drought occurrence is observed for some regions. The findings are useful for policymakers and practitioners to improve water resources planning and management, in particular to minimise drought effects in the future. Future research shall address the influence of topography on drought behaviour using more meteorological stations and to include east Malaysia in the analysis.

Water Availability in Indus River at the Upper Indus Basin under Different Climate Change Scenarios

NASA Astrophysics Data System (ADS)

Khan, Firdos; Pilz, Jürgen

2015-04-01

The last decade of the 20th century and the first decade of the 21st century showed that climate change or global warming is happening and the latter one is considered as the warmest decade over Pakistan ever in history where temperature reached 53 0C on May 26, 2010. The changing climate has impact on various areas including agriculture, water, health, among others. There are two main forces which have central role in changing climate: one is natural variability and the other one is human evoked changes, increasing the density of green house gases. The elements in the bunch of Energy-Food-Water are interlinked with one another and among them water plays a crucial role for the existence of the other two parts. This nexus is the central environmental issue around the globe generally, and is of particular importance in the developing countries. The study evaluated the importance and the availability of water in Indus River under different emission scenarios. Four emission scenarios are included, that is, the A2, B2, RCP4.5 and RCP8.5. One way coupling of regional climate models (RCMs) and Hydrological model have been implemented in this study. The PRECIS (Providing Regional Climate for Impact Studies) and CCAM (Conformal-Cubic Atmospheric Model) climate models and UBCWM (University of British Columbia Watershed Model) hydrological model are used for this purpose. It is observed that Indus River contributes 80 % of the hydro-power generation and contributes 44 % to available water annually in Pakistan. It is further investigated whether sufficient water will be available in the Indus River under climate change scenarios. Toward this goal, Tarbela Reservoir is used as a measurement tool using the parameters of the reservoir like maximum operating storage, dead level storage, discharge capacity of tunnels and spillways. The results of this study are extremely important for the economy of Pakistan in various key areas like agriculture, energy, industries and ecosystem

Summary of resources available to small water systems for meeting the 10 ppb arsenic drinking water limit.

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

Krumhansl, James Lee; Thomson, Bruce M.; Ziegler, Matt

2007-01-01

With the lowering of the EPA maximum contaminant level of arsenic from 50 parts per billion (ppb) to 10 ppb, many public water systems in the country and in New Mexico in particular, are faced with making decisions about how to bring their system into compliance. This document provides detail on the options available to the water systems and the steps they need to take to achieve compliance with this regulation. Additionally, this document provides extensive resources and reference information for additional outreach support, financing options, vendors for treatment systems, and media pilot project results.

Potential climate change impacts on water availability and cooling water demand in the Lusatian Lignite Mining Region, Central Europe

NASA Astrophysics Data System (ADS)

Pohle, Ina; Koch, Hagen; Gädeke, Anne; Grünewald, Uwe; Kaltofen, Michael; Redetzky, Michael

2014-05-01

In the catchments of the rivers Schwarze Elster, Spree and Lusatian Neisse, hydrologic and socioeconomic systems are coupled via a complex water management system in which water users, reservoirs and water transfers are included. Lignite mining and electricity production are major water users in the region: To allow for open pit lignite mining, ground water is depleted and released into the river system while cooling water is used in the thermal power plants. In order to assess potential climate change impacts on water availability in the catchments as well as on the water demand of the thermal power plants, a climate change impact assessment was performed using the hydrological model SWIM and the long term water management model WBalMo. The potential impacts of climate change were considered by using three regional climate change scenarios of the statistical regional climate model STAR assuming a further temperature increase of 0, 2 or 3 K by the year 2050 in the region respectively. Furthermore, scenarios assuming decreasing mining activities in terms of a decreasing groundwater depression cone, lower mining water discharges, and reduced cooling water demand of the thermal power plants are considered. In the standard version of the WBalMo model cooling water demand is considered as static with regard to climate variables. However, changes in the future cooling water demand over time according to the plans of the local mining and power plant operator are considered. In order to account for climate change impacts on the cooling water demand of the thermal power plants, a dynamical approach for calculating water demand was implemented in WBalMo. As this approach is based on air temperature and air humidity, the projected air temperature and air humidity of the climate scenarios at the locations of the power plants are included in the calculation. Due to increasing temperature and decreasing precipitation declining natural and managed discharges, and hence a lower

Stochastic estimation of plant-available soil water under fluctuating water table depths

NASA Astrophysics Data System (ADS)

Or, Dani; Groeneveld, David P.

1994-12-01

Preservation of native valley-floor phreatophytes while pumping groundwater for export from Owens Valley, California, requires reliable predictions of plant water use. These predictions are compared with stored soil water within well field regions and serve as a basis for managing groundwater resources. Soil water measurement errors, variable recharge, unpredictable climatic conditions affecting plant water use, and modeling errors make soil water predictions uncertain and error-prone. We developed and tested a scheme based on soil water balance coupled with implementation of Kalman filtering (KF) for (1) providing physically based soil water storage predictions with prediction errors projected from the statistics of the various inputs, and (2) reducing the overall uncertainty in both estimates and predictions. The proposed KF-based scheme was tested using experimental data collected at a location on the Owens Valley floor where the water table was artificially lowered by groundwater pumping and later allowed to recover. Vegetation composition and per cent cover, climatic data, and soil water information were collected and used for developing a soil water balance. Predictions and updates of soil water storage under different types of vegetation were obtained for a period of 5 years. The main results show that: (1) the proposed predictive model provides reliable and resilient soil water estimates under a wide range of external conditions; (2) the predicted soil water storage and the error bounds provided by the model offer a realistic and rational basis for decisions such as when to curtail well field operation to ensure plant survival. The predictive model offers a practical means for accommodating simple aspects of spatial variability by considering the additional source of uncertainty as part of modeling or measurement uncertainty.

Climate change impacts on water availability: developing regional scenarios for agriculture of the Former Soviet Union countries of Central Asia

NASA Astrophysics Data System (ADS)

Kirilenko, A.; Dronin, N.

2010-12-01

Water is the major factor, limiting agriculture of the five Former Soviet Union (FSU) of Central Asia. Elevated topography prevents moist and warm air from the Atlantic and Indian Oceans from entering the region.With exception of Kazakhstan, agriculture is generally restricted to oases and irrigated lands along the major rivers and canals. Availability of water for irrigation is the major factor constraining agriculture in the region, and conflicts over water are not infrequent. The current water crisis in the region is largely due to human activity; however the region is also strongly impacted by the climate. In multiple locations, planned and autonomous adaptations to climate change have already resulted in changes in agriculture, such as a dramatic increase in irrigation, or shift in crops towards the ones better suited for warmer and dryer climate; however, it is hard to differentiate between the effects of overall management improvement and the avoidance of climate-related losses. Climate change will contribute to water problems, escalating irrigation demand during the drought period, and increasing water loss with evaporation. The future of the countries of the Aral Sea basin then depends on both the regional scenario of water management policy and a global scenario of climate change, and is integrated with global socioeconomic scenarios. We formulate a set of regional policy scenarios (“Business as Usual”, “Falling Behind” and “Closing the Gap”) and demonstrate how each of them corresponds to IPCC SRES scenarios, the latter used as an input to the General Circulation Models (GCMs). Then we discuss the relative effectiveness of the introduced scenarios for mitigating water problems in the region, taking into account the adaptation through changing water demand for agriculture. Finally, we introduce the results of multimodel analysis of GCM climate projections, especially in relation to the change in precipitation and frequency of droughts, and

Application of factor analysis to the water quality in reservoirs

NASA Astrophysics Data System (ADS)

Silva, Eliana Costa e.; Lopes, Isabel Cristina; Correia, Aldina; Gonçalves, A. Manuela

2017-06-01

In this work we present a Factor Analysis of chemical and environmental variables of the water column and hydro-morphological features of several Portuguese reservoirs. The objective is to reduce the initial number of variables, keeping their common characteristics. Using the Factor Analysis, the environmental variables measured in the epilimnion and in the hypolimnion, together with the hydromorphological characteristics of the dams were reduced from 63 variables to only 13 factors, which explained a total of 83.348% of the variance in the original data. After performing rotation using the Varimax method, the relations between the factors and the original variables got clearer and more explainable, which provided a Factor Analysis model for these environmental variables using 13 varifactors: Water quality and distance to the source, Hypolimnion chemical composition, Sulfite-reducing bacteria and nutrients, Coliforms and faecal streptococci, Reservoir depth, Temperature, Location, among other factors.

Optimizing available water capacity using microwave satellite data for improving irrigation management

NASA Astrophysics Data System (ADS)

Gupta, Manika; Bolten, John; Lakshmi, Venkat

2015-04-01

This work addresses the improvement of available water capacity by developing a technique for estimating soil hydraulic parameters through the utilization of satellite-retrieved near surface soil moisture. The prototype involves the usage of Monte Carlo analysis to assimilate historical remote sensing soil moisture data available from the Advanced Microwave Scanning Radiometer (AMSR-E) within the hydrological model. The main hypothesis used in this study is that near-surface soil moisture data contain useful information that can describe the effective hydrological conditions of the basin such that when appropriately In the method followed in this study the hydraulic parameters are derived directly from information on the soil moisture state at the AMSR-E footprint scale and the available water capacity is derived for the root zone by coupling of AMSR-E soil moisture with the physically-based hydrological model. The available capacity water, which refers to difference between the field capacity and wilting point of the soil and represent the soil moisture content at 0.33 bar and 15 bar respectively is estimated from the soil hydraulic parameters using the van Genuchten equation. The initial ranges of soil hydraulic parameters are taken in correspondence with the values available from the literature based on Soil Survey Geographic (SSURGO) database within the particular AMSR-E footprint. Using the Monte Carlo simulation, the ranges are narrowed in the region where simulation shows a good match between predicted and near-surface soil moisture from AMSR-E. In this study, the uncertainties in accurately determining the parameters of the nonlinear soil water retention function for large-scale hydrological modeling is the focus of the development of the Bayesian framework. Thus, the model forecasting has been combined with the observational information to optimize the model state and the soil hydraulic parameters simultaneously. The optimization process is divided into

Projections of Declining Surface-Water Availability for the Southwestern United States

NASA Technical Reports Server (NTRS)

Seager, Richard; Ting, Mingfang; Li, Cuihua; Naik, Naomi; Cook, Benjamin; Nakamura, Jennifer; Liu, Haibo

2012-01-01

Global warming driven by rising greenhouse-gas concentrations is expected to cause wet regions of the tropics and mid to high latitudes to get wetter and subtropical dry regions to get drier and expand polewards. Over southwest North America, models project a steady drop in precipitation minus evapotranspiration, P -- E, the net flux of water at the land surface, leading to, for example, a decline in Colorado River flow. This would cause widespread and important social and ecological consequences. Here, using new simulations from the Coupled Model Intercomparison Project Five, to be assessed in Intergovernmental Panel on Climate Change Assessment Report Five, we extend previous work by examining changes in P, E, runoff and soil moisture by season and for three different water resource regions. Focusing on the near future, 2021-2040, the new simulations project declines in surface-water availability across the southwest that translate into reduced soil moisture and runoff in California and Nevada, the Colorado River headwaters and Texas.

Climate Change and Future U.S. Electricity Infrastructure: the Nexus between Water Availability, Land Suitability, and Low-Carbon Technologies

NASA Astrophysics Data System (ADS)

Rice, J.; Halter, T.; Hejazi, M. I.; Jensen, E.; Liu, L.; Olson, J.; Patel, P.; Vernon, C. R.; Voisin, N.; Zuljevic, N.

2014-12-01

Integrated assessment models project the future electricity generation mix under different policy, technology, and socioeconomic scenarios, but they do not directly address site-specific factors such as interconnection costs, population density, land use restrictions, air quality, NIMBY concerns, or water availability that might affect the feasibility of achieving the technology mix. Moreover, since these factors can change over time due to climate, policy, socioeconomics, and so on, it is important to examine the dynamic feasibility of integrated assessment scenarios "on the ground." This paper explores insights from coupling an integrated assessment model (GCAM-USA) with a geospatial power plant siting model (the Capacity Expansion Regional Feasibility model, CERF) within a larger multi-model framework that includes regional climate, hydrologic, and water management modeling. GCAM-USA is a dynamic-recursive market equilibrium model simulating the impact of carbon policies on global and national markets for energy commodities and other goods; one of its outputs is the electricity generation mix and expansion at the state-level. It also simulates water demands from all sectors that are downscaled as input to the water management modeling. CERF simulates siting decisions by dynamically representing suitable areas for different generation technologies with geospatial analyses (informed by technology-specific siting criteria, such as required mean streamflow per the Clean Water Act), and then choosing siting locations to minimize interconnection costs (to electric transmission and gas pipelines). CERF results are compared across three scenarios simulated by GCAM-USA: 1) a non-mitigation scenario (RCP8.5) in which conventional fossil-fueled technologies prevail, 2) a mitigation scenario (RCP4.5) in which the carbon price causes a shift toward nuclear, carbon capture and sequestration (CCS), and renewables, and 3) a repeat of scenario (2) in which CCS technologies are

Estimated water use and availability in the Pawtuxet and Quinebaug River basins, Rhode Island, 1995-99

USGS Publications Warehouse

Wild, Emily C.; Nimiroski, Mark T.

2007-01-01

Water availability became a concern in Rhode Island during a drought in 1999, and an investigation was needed to assess demands on the hydrologic system from withdrawals during periods of little to no precipitation. The low water levels during the drought prompted the U.S. Geological Survey and the Rhode Island Water Resources Board to begin a series of studies on water use and availability in each drainage area in Rhode Island for 1995–99. The study area for this report, which includes the Pawtuxet River Basin in central Rhode Island (231.6 square miles) and the Quinebaug River Basin in western Rhode Island (60.97 square miles), was delineated as the surface-water drainage areas of these basins. During the study period from 1995 through 1999, two major water suppliers withdrew an average of 71.86 million gallons per day (Mgal/d) from the Pawtuxet River Basin; of this amount, about 35.98 Mgal/d of potable water were exported to other basins in Rhode Island. The estimated water withdrawals from minor water suppliers were 0.026 Mgal/d in the Pawtuxet River Basin and 0.003 Mgal/d in the Quinebaug River Basin. Total self-supply withdrawals were 2.173 Mgal/d in the Pawtuxet River Basin and 0.360 Mgal/d in the Quinebaug River Basin, which has no public water supply. Total water use averaged 18.07 Mgal/d in the Pawtuxet River Basin and 0.363 Mgal/d in the Quinebaug River Basin. Total return flow in the Pawtuxet River Basin was 30.64 Mgal/d, which included about 12.28 Mgal/d that were imported from other basins in Rhode Island. Total return flow was 0.283 Mgal/d in the Quinebaug River Basin. During times of little to no recharge in the form of precipitation, the surface- and ground-water flows are from storage primarily in the stratified sand and gravel deposits; water also flows through the till deposits, but at a slower rate. The ground water discharging to the streams during times of little to no recharge from precipitation is referred to as base flow. The PART

Asynchronous Amazon Forest Canopy Phenology Indicates Adaptation to Both Water and Light Availability

NASA Astrophysics Data System (ADS)

Jones, M. O.; Kimball, J. S.; Nemani, R. R.

2015-12-01

Amazon forests represent nearly half of all tropical vegetation biomass and, through photosynthesis and respiration, annually process more than twice the amount of estimated carbon (CO2) from fossil fuel emissions. Yet the seasonality of Amazon canopy cover, and the extent to which seasonal fluctuations in water availability and photosynthetically active radiation influence these processes, is still poorly understood. Implementing six remotely sensed data sets spanning nine years (2003-2011), with reported field and flux tower data, we show that southern equatorial Amazon forests exhibit a distinctive seasonal signal. Seasonal timing of water availability, canopy biomass growth and net leaf flush are asynchronous in regions with short dry seasons and become more synchronous across a west-to-east longitudinal moisture gradient of increasing dry season length. Forest cover is responsive to seasonal disparities in both water and solar radiation availability, temporally adjusting net leaf flush to maximize use of these generally abundant resources, while reducing drought susceptibility. An accurate characterization of this asynchronous behavior allows for improved understanding of canopy phenology across contiguous tropical forests and their sensitivity to climate variability and drought. These insights can also inform land surface models to provide a more accurate representation of seasonal forest carbon allocation strategies responsive to environmental drivers.

Summary of available state ambient stream-water-quality data, 1990-98, and limitations for national assessment

USGS Publications Warehouse

Pope, Larry M.; Rosner, Stacy M.; Hoffman, Darren C.; Ziegler, Andrew C.

2004-01-01

of these factors, a high level of uncertainty exists in a national assessment of water quality. The purpose of this report is to present a summary of electronically available State ambient stream-water-quality data for 10 selected constituents and measurements from monitoring sites with nine or more analyses for 199098 and to discuss limitations for use of the data for national assessment. These analyses were statistiscally summarized by monitoring site and State, and the results presented in tabular format. Most of the selected constituents or measurements have U.S. Environmental Protection Agency criteria or guidelines for aquatic-life or drinking-water purposes. A significant finding of this investigation is that for a large percentage of monitoring sites in the Nation, there are insufficient data to meet U.S. Environmental Protection Agency recommendations for determining if water-quality conditions are degraded and for making informed decisions regarding total maximum daily loads.

Climate change reduces water availability for agriculture by decreasing non-evaporative irrigation losses

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.

Water availability as dominant control of heat stress responses in two contrasting tree species.

PubMed

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

Ground-Water Availability from the Hawi Aquifer in the Kohala Area, Hawaii

USGS Publications Warehouse

Underwood, Mark R.; Meyer, William; Souza, William R.

1995-01-01

A ground-water study consisting of test-well drilling, aquifer tests, and numerical simulation was done to investigate ground-water availability in the basal part of the Hawi aquifer between the western drainage divide of Pololu Valley and Upolu Point in Kohala, Hawaii. The test-well drilling provided information on geology, water levels, water quality, vertical extent of the freshwater, and the thickness of the freshwater-saltwater transition zone in that aquifer. A total of 12 test wells were drilled at eight locations. Aquifer tests were done at five locations to estimate the hydraulic conductivity of the aquifer. Using information on the distribution of recharge, vertical extent of freshwater, hydraulic conductivity, and geometry of the basal aquifer, a numerical model was used to simulate the movement of water into, through, and out of the basal aquifer, and the effect of additional pumping on the water levels in the aquifer. Results of the modeling indicate that ground-water withdrawal of 20 million gallons per day above the existing withdrawal of 0.6 million gallons per day from the basal aquifer is hydrologically feasible, but that spacing, depth, and pumping rates of individual wells are important. If pumping is concentrated, the likelihood of saltwater intrusion is increased. The additional withdrawal of 20 million gallons per day would result in a reduction of ground-water discharge to the ocean by an amount equal to pumpage. Although model-calculated declines in water-level outside the area of pumping are small, pumping could cause some reduction of streamflow near the mouth of Pololu Stream.

Implications of Upstream Flow Availability for Watershed Surface Water Supply Across the Conterminous United States

Treesearch

Kai Duan; Ge Sun; Peter V. Caldwell; Steven G. McNulty; Yang Zhang

2018-01-01

Although it is well established that the availability of upstream flow (AUF) affects downstream water supply, its significance has not been rigorously categorized and quantified at fine resolutions. This study aims to fill this gap by providing a nationwide inventory of AUF and local water resource, and assessing their roles in securing water supply across the 2,099 8-...

Freshwater availability and water fetching distance affect child health in sub-Saharan Africa.

PubMed

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.

Impact of root growth and root hydraulic conductance on water availability of young walnut trees

NASA Astrophysics Data System (ADS)

Jerszurki, Daniela; Couvreur, Valentin; Hopmans, Jan W.; Silva, Lucas C. R.; Shackel, Kenneth A.; de Souza, Jorge L. M.

2015-04-01

Walnut (Juglans regia L.) is a tree species of high economic importance in the Central Valley of California. This crop has particularly high water requirements, which makes it highly dependent on irrigation. The context of decreasing water availability in the state calls for efficient water management practices, which requires improving our understanding of the relationship between water application and walnut water availability. In addition to the soil's hydraulic conductivity, two plant properties are thought to control the supply of water from the bulk soil to the canopy: (i) root distribution and (ii) plant hydraulic conductance. Even though these properties are clearly linked to crop water requirements, their quantitative relation remains unclear. The aim of this study is to quantitatively explain walnut water requirements under water deficit from continuous measurements of its water consumption, soil and stem water potential, root growth and root system hydraulic conductance. For that purpose, a greenhouse experiment was conducted for a two month period. Young walnut trees were planted in transparent cylindrical pots, equipped with: (i) rhizotron tubes, which allowed for non-invasive monitoring of root growth, (ii) pressure transducer tensiometers for soil water potential, (iii) psychrometers attached to non-transpiring leaves for stem water potential, and (iv) weighing scales for plant transpiration. Treatments consisted of different irrigation rates: 100%, 75% and 50% of potential crop evapotranspiration. Plant responses were compared to predictions from three simple process-based soil-plant-atmosphere models of water flow: (i) a hydraulic model of stomatal regulation based on stem water potential and vapor pressure deficit, (ii) a model of plant hydraulics predicting stem water potential from soil-root interfaces water potential, and (iii) a model of soil water depletion predicting the water potential drop between the bulk soil and soil-root interfaces

Probabilities of having minimum amounts of available soil water at wheat planting

USDA-ARS?s Scientific Manuscript database

Winter wheat (Triticum aestivum L.)-fallow (WF) remains a prominent cropping system throughout the Central Great Plains despite documentation confirming the inefficiency of precipitation storage during the second summer fallow period. Wheat yield is greatly influenced by available soil water at plan...

Current and projected water demand and water availability estimates under climate change scenarios in the Weyib River basin in Bale mountainous area of Southeastern Ethiopia

NASA Astrophysics Data System (ADS)

Serur, Abdulkerim Bedewi; Sarma, Arup Kumar

2017-07-01

This study intended to estimate the spatial and temporal variation of current and projected water demand and water availability under climate change scenarios in Weyib River basin, Bale mountainous area of Southeastern Ethiopia. Future downscaled climate variables from three Earth System Models under the three RCP emission scenarios were inputted into ArcSWAT hydrological model to simulate different components of water resources of a basin whereas current and projected human and livestock population of the basin is considered to estimate the total annual water demand for various purposes. Results revealed that the current total annual water demand of the basin is found to be about 289 Mm3, and this has to increase by 83.47% after 15 years, 200.67% after 45 years, and 328.78% after 75 years by the 2020s, 2050s, and 2080s, respectively, from base period water demand mainly due to very rapid increasing population (40.81, 130.80, and 229.12% by the 2020s, 2050s, and 2080s, respectively) and climatic variability. The future average annual total water availability in the basin is observed to be increased by ranging from 15.04 to 21.61, 20.08 to 23.34, and 16.21 to 39.53% by the 2020s, 2050s, and 2080s time slice, respectively, from base period available water resources (2333.39 Mm3). The current water availability per capita per year of the basin is about 3112.23 m3 and tends to decline ranging from 11.78 to 17.49, 46.02 to 47.45, and 57.18 to 64.34% by the 2020s, 2050s, and 2080s, respectively, from base period per capita per year water availability. This indicated that there might be possibility to fall the basin under water stress condition in the long term.

Balancing global water availability and use at basin scale in an integrated assessment model

DOE PAGES

Kim, Son H.; Hejazi, Mohamad; Liu, Lu; ...

2016-01-22

Water is essential for the world’s food supply, for energy production, including bioenergy and hydroelectric power, and for power system cooling. Water is already scarce in many regions of the world and could present a critical constraint as society attempts simultaneously to mitigate climate forcing and adapt to climate change, and to provide for a larger and more prosperous human population. Numerous studies have pointed to growing pressures on the world’s scarce fresh water resources from population and economic growth, and climate change. This study goes further. We use the Global Change Assessment Model to analyze interactions between population, economicmore » growth, energy, land, and water resources simultaneously in a dynamically evolving system where competing claims on water resources from all claimants—energy, land, and economy—are reconciled with water resource availability—from renewable water, non-renewable groundwater and desalinated water sources —across 14 geopolitical regions, 151 agriculture-ecological zones, and 235 major river basins. We find that previous estimates of global water withdrawal projections are overestimated. Model simulations show that it is more economical in some basins to alter agricultural and energy activities rather than utilize non-renewable groundwater or desalinated water. Lastly, this study highlights the importance of accounting for water as a binding factor in agriculture, energy and land use decisions in integrated assessment models and implications for global responses to water scarcity, particularly in the trade of agricultural commodities and land-use decisions.« less

Balancing global water availability and use at basin scale in an integrated assessment model

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

Kim, Son H.; Hejazi, Mohamad; Liu, Lu

Water is essential for the world’s food supply, for energy production, including bioenergy and hydroelectric power, and for power system cooling. Water is already scarce in many regions of the world and could present a critical constraint as society attempts simultaneously to mitigate climate forcing and adapt to climate change, and to provide for a larger and more prosperous human population. Numerous studies have pointed to growing pressures on the world’s scarce fresh water resources from population and economic growth, and climate change. This study goes further. We use the Global Change Assessment Model to analyze interactions between population, economicmore » growth, energy, land, and water resources simultaneously in a dynamically evolving system where competing claims on water resources from all claimants—energy, land, and economy—are reconciled with water resource availability—from renewable water, non-renewable groundwater and desalinated water sources —across 14 geopolitical regions, 151 agriculture-ecological zones, and 235 major river basins. We find that previous estimates of global water withdrawal projections are overestimated. Model simulations show that it is more economical in some basins to alter agricultural and energy activities rather than utilize non-renewable groundwater or desalinated water. Lastly, this study highlights the importance of accounting for water as a binding factor in agriculture, energy and land use decisions in integrated assessment models and implications for global responses to water scarcity, particularly in the trade of agricultural commodities and land-use decisions.« less

High water availability increases the negative impact of a native hemiparasite on its non-native host

PubMed Central

Cirocco, Robert M.; Facelli, José M.; Watling, Jennifer R.

2016-01-01

Environmental factors alter the impacts of parasitic plants on their hosts. However, there have been no controlled studies on how water availability modulates stem hemiparasites’ effects on hosts. A glasshouse experiment was conducted to investigate the association between the Australian native stem hemiparasite Cassytha pubescens and the introduced host Ulex europaeus under high (HW) and low (LW) water supply. Cassytha pubescens had a significant, negative effect on the total biomass of U. europaeus, which was more severe in HW than LW. Regardless of watering treatment, infection significantly decreased shoot and root biomass, nodule biomass, nodule biomass per unit root biomass, F v/F m, and nitrogen concentration of U. europaeus. Host spine sodium concentration significantly increased in response to infection in LW but not HW conditions. Host water potential was significantly higher in HW than in LW, which may have allowed the parasite to maintain higher stomatal conductances in HW. In support of this, the δ13C of the parasite was significantly lower in HW than in LW (and significantly higher than the host). C. pubescens also had significantly higher F v/F m and 66% higher biomass per unit host in the HW compared with the LW treatment. The data suggest that the enhanced performance of C. pubescens in HW resulted in higher parasite growth rates and thus a larger demand for resources from the host, leading to poorer host performance in HW compared with LW. C. pubescens should more negatively affect U. europaeus growth under wet conditions rather than under dry conditions in the field. PMID:26703920

Comparing hydraulic properties of soil-less substrates with natural soils: a more detailed look at hydraulic properties and their impact on plant water availability

NASA Astrophysics Data System (ADS)

Crawford, L.; Rivera, L. D.; van Iersel, M.

2013-12-01

Moisture release curves are often used when assessing plant-water relationships in soil-less substrates. However, differences between natural soils and soilless substrates make traditional assumptions about plant available water potentially invalid. If soil-less substrates are supposed to be treated like natural soils; why do plants begin wilting at very low water potentials (-10 to -30 kPa) and there is anywhere between 20 to 40 % water left (on a volumetric basis) in the soil (Abad et al., 2005; Arguedas et al., 2006; Ristvey et al, 2008) . We hypothesize that the fault lies in the methods used and the assumption that water potential is the only limiting factor in water availability to plants. Hydraulic properties, including the relationships that exist between plant available water, water content, and hydraulic conductivity of soil-less substrates have traditionally been characterized using instrumentation such as pressure plates, hanging water columns, and tempe cells. These approaches typically take a months and only provide data on select segments of the soil moisture release curve, and in the case of pressure plates and hanging water columns hydraulic conductivity is ignored and not very well understood. Using the Wind/Schindler Evaporation method more detailed measurements of these hydraulic properties can be measured in a less than a week. A more detailed look at the hydraulic properties of soil-less substrates and how they compare with natural soils may give us more insight into soil-plant-water-relations and what limits availability of water to plants. Soil moisture release curves and hydraulic conductivity curves of different soil-less substrates were compared with curves from typical agriculture soils to give insight into how these properties compare. Results of the soil moisture release curves showed that some soil-less substrates had comparable moisture release curves to agricultural soils while others had bi-modal curves indicating gap-gradation in

Water use and availability in the Woonasquatucket and Moshassuck River basins, north-central Rhode Island

USGS Publications Warehouse

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

The relationships between leaf economics and hydraulic traits of woody plants depend on water availability.

PubMed

Yin, Qiulong; Wang, Lei; Lei, Maolin; Dang, Han; Quan, Jiaxin; Tian, Tingting; Chai, Yongfu; Yue, Ming

2018-04-15

Leaf economics and hydraulic traits are simultaneously involved in the process of trading water for CO 2 , but the relationships between these two suites of traits remain ambiguous. Recently, Li et al. (2015) reported that leaf economics and hydraulic traits were decoupled in five tropical-subtropical forests in China. We tested the hypothesis that the relationships between economics and hydraulic traits may depend on water availability. We analysed five leaf economics traits, four hydraulic traits and anatomical structures of 47 woody species on the Loess Plateau with poor water availability and compared those data with Li et al. (2015) obtained in tropical-subtropical regions with adequate water. The results showed that plants on the Loess Plateau tend to have higher leaf tissue density (TD), leaf nitrogen concentrations and venation density (VD) and lower stomatal guard cell length (SL) and maximum stomatal conductance to water vapour (g wmax ). VD showed positive correlations with leaf nitrogen concentrations, palisade tissue thickness (PT) and ratio of palisade tissue thickness to spongy tissue thickness (PT/ST). Principal component analysis (PCA) showed a result opposite from those of tropical-subtropical regions: leaf economics and hydraulic traits were coupled on the Loess Plateau. A stable correlation between these two suites of traits may be more cost-effective on the Loess Plateau, where water availability is poor. The correlation of leaf economics and hydraulic traits may be a type of adaptation mechanism in arid conditions. Copyright © 2017 Elsevier B.V. All rights reserved.

Water availability and quality in the Gulf Cooperation Council countries: implications for public health.

PubMed

Sherif, Mohsen

2010-07-01

Environmental problems and their potential impacts on public health vary in scale and time depending on the level and nature of pollutants. Although water is regarded as the source of all kinds of life on earth, it also acts as an efficient carrier of pollutants. Contamination of drinking water, agricultural water, or recreational water by infectious pathogens, chemical pollutants, or others can have significant impacts on public health. During the past few decades, waterborne diseases continued to spread and the health risks continued to increase. The correlation between water resources and public health is more evident in arid regions. This article discusses the availability of water resources in the Gulf Cooperation Council countries and elaborates on the possible impacts of water resources on public health. It emphasizes the importance of preservation of water quality and prevention of waterborne diseases, which could be achieved through a coordinated effort from diverse groups and disciplines.

Prediction in Ungauged Basins (PUB) for estimating water availability during water scarcity conditions: rainfall-runoff modelling of the ungauged diversion inflows to the Ridracoli water supply reservoir

NASA Astrophysics Data System (ADS)

Toth, Elena

2013-04-01

The Ridracoli reservoir is the main drinking water supply reservoir serving the whole Romagna region, in Northern Italy. Such water supply system has a crucial role in an area where the different characteristics of the communities to be served, their size, the mass tourism and the presence of food industries highlight strong differences in drinking water needs. Its operation allows high quality drinking water supply to a million resident customers, plus a few millions of tourists during the summer of people and it reduces the need for water pumping from underground sources, and this is particularly important since the coastal area is subject also to subsidence and saline ingression into aquifers. The system experienced water shortage conditions thrice in the last decade, in 2002, in 2007 and in autumn-winter 2011-2012, when the reservoir water storage fell below the attention and the pre-emergency thresholds, thus prompting the implementation of a set of mitigation measures, including limitations to the population's water consumption. The reservoir receives water not only from the headwater catchment, closed at the dam, but also from four diversion watersheds, linked to the reservoir through an underground water channel. Such withdrawals are currently undersized, abstracting only a part of the streamflow exceeding the established minimum flows, due to the design of the water intake structures; it is therefore crucial understanding how the reservoir water availability might be increased through a fuller exploitation of the existing diversion catchment area. Since one of the four diversion catchment is currently ungauged (at least at the fine temporal scale needed for keeping into account the minimum flow requirements downstream of the intakes), the study first presents the set up and parameterisation of a continuous rainfall-runoff model at hourly time-step for the three gauged diversion watersheds and for the headwater catchment: a regional parameterisation

Balancing global water availability and use at basin scale in an integrated assessment model

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

Kim, Son H.; Hejazi, Mohamad; Liu, Lu

Water is essential for the world’s food supply, for energy production, including bioenergy and hydroelectric power, and for power system cooling. Water is already scarce in many regions of the world and could present a critical constraint as society attempts simultaneously to mitigate climate forcing and adapt to climate change, and to provide for a larger and more prosperous human population. Numerous studies have pointed to growing pressures on the world’s scarce fresh water resources from population and economic growth, and climate change. This study goes further. We use the Global Change Assessment Model to analyze interactions between population, economicmore » growth, energy, land and water resources simultaneously in a dynamically evolving system where competing claims on water resources from all claimants—energy, land, and economy—are reconciled with water resource availability—from renewable water, non-renewable groundwater sources and desalinated water—across 14 geopolitical regions, 151 agriculture-ecological zones, and 235 major river basins. We find that previous estimates of global water withdrawal projections are overestimated. Model simulations show that it is more economical in some basins to alter agricultural and energy activities rather than utilize non-renewable groundwater or desalinated water. This study highlights the importance of accounting for water as a binding factor in agriculture, energy and land use decisions in IAMs and implications for global responses to water scarcity, particularly in the trade of agricultural commodities and land-use decisions.« less

Particle water and pH in the eastern Mediterranean: source variability and implications for nutrient availability

NASA Astrophysics Data System (ADS)

Bougiatioti, Aikaterini; Nikolaou, Panayiota; Stavroulas, Iasonas; Kouvarakis, Giorgos; Weber, Rodney; Nenes, Athanasios; Kanakidou, Maria; Mihalopoulos, Nikolaos

2016-04-01

Particle water (liquid water content, LWC) and aerosol pH are important parameters of the aerosol phase, affecting heterogeneous chemistry and bioavailability of nutrients that profoundly impact cloud formation, atmospheric composition, and atmospheric fluxes of nutrients to ecosystems. Few measurements of in situ LWC and pH, however, exist in the published literature. Using concurrent measurements of aerosol chemical composition, cloud condensation nuclei activity, and tandem light scattering coefficients, the particle water mass concentrations associated with the aerosol inorganic (Winorg) and organic (Worg) components are determined for measurements conducted at the Finokalia atmospheric observation station in the eastern Mediterranean between June and November 2012. These data are interpreted using the ISORROPIA-II thermodynamic model to predict the pH of aerosols originating from the various sources that influence air quality in the region. On average, closure between predicted aerosol water and that determined by comparison of ambient with dry light scattering coefficients was achieved to within 8 % (slope = 0.92, R2 = 0.8, n = 5201 points). Based on the scattering measurements, a parameterization is also derived, capable of reproducing the hygroscopic growth factor (f(RH)) within 15 % of the measured values. The highest aerosol water concentrations are observed during nighttime, when relative humidity is highest and the collapse of the boundary layer increases the aerosol concentration. A significant diurnal variability is found for Worg with morning and afternoon average mass concentrations being 10-15 times lower than nighttime concentrations, thus rendering Winorg the main form of particle water during daytime. The average value of total aerosol water was 2.19 ± 1.75 µg m-3, contributing on average up to 33 % of the total submicron mass concentration. Average aerosol water associated with organics, Worg, was equal to 0.56 ± 0.37 µg m-3; thus, organics

Atrazine and metolachlor occurrence in shallow ground water of the United States, 1993 to 1995: Relations to explanatory factors

USGS Publications Warehouse

Kolpin, D.W.; Barbash, J.E.; Gilliom, R.J.

2002-01-01

Since 1991, the U.S. Geological Survey has been conducting the National Water Quality Assessment (NAWQA) Program to determine the quality of the Nation's water resources. In an effort to obtain a better understanding of why pesticides are found in shallow ground water on a national scale, a set of factors likely to affect the fate and transport of two herbicides in the subsurface were examined. Atrazine and metolachlor were selected for this discussion because they were among the most frequently detected pesticides in ground water during the first phase of the NAWQA Program (1993 to 1995), and each was the most frequently detected compound in its chemical class (triazines and acetanilides, respectively). The factors that most strongly correlated with the frequencies of atrazine detection in shallow ground-water networks were those that provided either: (1) an indication of the potential susceptibility of ground water to atrazine contamination, or (2) an indication of relative ground-water age. The factors most closely related to the frequencies of metolachlor detection in ground water, however, were those that estimated or indicated the intensity of the agricultural use of metolachlor. This difference is probably the result of detailed use estimates for these compounds being available only for agricultural settings. While atrazine use is relatively extensive in nonagricultural settings, in addition to its widespread agricultural use, metolachlor is used almost exclusively for agricultural purposes. As a result, estimates of agricultural applications provide a less reliable indication of total chemical use for atrazine than for metolachlor. A multivariate analysis demonstrated that the factors of interest explained about 50 percent of the variance in atrazine and metolachlor detection frequencies among the NAWQA land-use studies examined. The inclusion of other factors related to pesticide fate and transport in ground water, or improvements in the quality and

Estimated water use and availability in the South Coastal Drainage Basin, southern Rhode Island, 1995-99

USGS Publications Warehouse

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

76 FR 79176 - Notice of Availability of Draft Recreational Water Quality Criteria and Request for Scientific Views

Federal Register 2010, 2011, 2012, 2013, 2014

2011-12-21

... ENVIRONMENTAL PROTECTION AGENCY [EPA-OW-2011-0466; FRL-9609-3] Notice of Availability of Draft Recreational Water Quality Criteria and Request for Scientific Views AGENCY: Environmental Protection Agency... Environmental Protection Agency (EPA) is announcing the availability of the draft document Recreational Water...

Differential responses of Picea asperata and Betula albosinensis to nitrogen supply imposed by water availability.

PubMed

Yin, Chunying; Palmroth, Sari; Pang, Xueyong; Tang, Bo; Liu, Qing; Oren, Ram

2018-05-16

A pot experiment was conducted to investigate the effects of nitrogen (N) addition (0, 20, 40 g N m-2 year-1, N0, N20, N40, respectively) on the growth, and biomass accumulation and allocation of coniferous and deciduous (Picea asperata Mast. and Betula albosinensis Burk.) seedlings under a range of soil moisture limitation (40%, 50%, 60%, 80% and 100% of field capacity, FC). At 100% FC, growth of shade-tolerant P. asperata increased with N supply, while that of shade-intolerant B. albosinensis reached a maximum at N20, declining somewhat thereafter. At 60% FC and lower moisture content, water availability limited the growth of P. asperata seedlings, while N availability became progressively limiting to growth with moisture increasing above 60% FC. The transition from principally water-limited response to N-limited response in B. albosinensis occurred at lower moisture content. For P. asperata, these patterns reflected the responses of roots, consistent with changes in root/shoot biomass. For B. albosinensis the response reflected changes in shoot dimensions and root biomass fraction, the latter decreasing with size and foliar [N]. We are not aware of another study demonstrating such differences in the shape of the growth responses of seedlings of differing potential growth rate, across a range in belowground resource supply. The responses of leaf photosynthesis (as well as photosynthetic water and N-use efficiencies) were consistent with the observed growth response of P. asperata to water and N availability, but not of B. albosinensis, suggesting that leaf area dynamics (not measured) dominated the response of this species. Betula albosinensis, a fast-growing species, has a relative narrow range of soil water and N availability for maximum growth, achieved by preferential allocation to the shoot as resources meet the requirements at moderate N and water supply. In contrast, P. asperata increases shoot biomass progressively with increasing resources up to moderate

Ground-water availability from surficial aquifers in the Red River of the North Basin, Minnesota

USGS Publications Warehouse

Reppe, Thomas H.C.

2005-01-01

On the basis of data and methods presented to evaluate ground-water availability, the Otter Tail and Pineland Sands surficial aquifers and Pelican River sand-plain aquifer have the greatest potential for additional development of ground-water resources in the study area.

Challenge theme 2: assuring water availability and quality in the 21st century: Chapter 4 in United States-Mexican Borderlands: Facing tomorrow's challenges through USGS science

USGS Publications Warehouse

Callegary, James; Langeman, Jeff; Leenhouts, Jim; Martin, Peter

2013-01-01

Along the United States–Mexican border, the health of communities, economies, and ecosystems is inextricably intertwined with the availability and quality of water, but effective water management in the Borderlands is complicated. Water users compete for resources, and their needs are increasing. Managers are faced with issues such as finding a balance between agriculture and rapidly growing cities or maintaining public supplies while ensuring sufficient resources for aquatic ecosystems. In addition to human factors, the dry climate of the Borderlands, as compared to more temperate regions, also increases the challenge of balancing water supplies between humans and ecosystems. Warmer, drier, and more variable conditions across the southwestern United States—the projected results of climate change (Seager and others, 2007)—would further stress water supplies.

Water use, ground-water recharge and availability, and quality of water in the Greenwich area, Fairfield County, Connecticut and Westchester County, New York, 2000-2002

USGS Publications Warehouse

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

Availability of data for monitoring noncommunicable disease risk factors in India

PubMed Central

Dandona, Rakhi; Dandona, Lalit

2012-01-01

Abstract Objective To examine the availability of data measuring noncommunicable disease (NCD) risk factor indicators from household surveys conducted in India from 2000 to 2009. Methods Questionnaires and publications used in household surveys were identified through internet and PubMed searches and examined to determine which core NCD risk factor indicators recommended by the World Health Organization (WHO) for NCD monitoring were being measured. Surveys with a sample size of 5000 or more were included to ensure a certain level of precision. The completeness of core indicator measurement and the geographical representativeness of the surveys were assessed. Findings Twenty six surveys met the inclusion criteria. Among the WHO-recommended core behavioural risk factor indicators, those monitoring tobacco use were measured completely in national and subnational surveys; those assessing dietary intake and physical inactivity were measured only in subnational surveys, and those assessing alcohol use were not measured at all. Among WHO-recommended core biological risk factors, only body mass index was measured in national and subnational surveys, whereas blood pressure, fasting blood glucose and blood cholesterol were measured only in subnational surveys. Due to the use of non-standard indicator definitions, measurement of core indicators in some of the national and subnational surveys was incomplete. Conclusion The availability of data on core risk factor indicators to monitor the increasing burden of NCDs is inadequate in India. These indicators using standardized definitions should be included in the periodic national household health surveys to provide data at the national and disaggregated levels. PMID:22271961

Developing Region-Specific Water Energy Intensity Factors for the U.S. Water System

NASA Astrophysics Data System (ADS)

Newmark, R. L.; Kandt, A.; Macknick, J.; Daw, J.; Hunsberger, R.; Tomberlin, G.

2014-12-01

Energy use by water and wastewater treatment plants equates to approximately 4% of total energy use in the United States. For many municipal water and wastewater treatment plants, energy costs related to pumping, treating, and transporting water represent a large fraction of total costs. The energy intensity of any given utility is heavily variant dependent on location and regional conditions, but energy requirements are generally expected to increase in many regions due to limits on water resources and regulatory requirements for water quality. Quantifying the energy use associated with our nation's water system - the energy needed to convey, extract, treat and distribute water in a particular location - is an important step in understanding the impact and interconnections of the water system on the energy system, in identifying opportunities for savings, and in improving existing modeling and analytic methods for both energy and water systems. Local topography and other regional conditions can greatly affect how much energy a particular water facility utilizes, which in turn affects its relationship with the broader electricity sector. This research evaluates what previous and current efforts have been undertaken to quantify water energy intensity factors (w-EIFs) on a regional scale, provides first steps for cataloguing resulting datasets and findings, and initiates a methodology for developing regional and localized w-EIFs. Improved regional w-EIFs can facilitate national reductions in energy intensity metrics by highlighting areas where energy savings opportunities could provide the greatest benefit.

Sensitivities and Tipping Points of Power System Operations to Fluctuations Caused by Water Availability and Fuel Prices

NASA Astrophysics Data System (ADS)

O'Connell, M.; Macknick, J.; Voisin, N.; Fu, T.

2017-12-01

The western US electric grid is highly dependent upon water resources for reliable operation. Hydropower and water-cooled thermoelectric technologies represent 67% of generating capacity in the western region of the US. While water resources provide a significant amount of generation and reliability for the grid, these same resources can represent vulnerabilities during times of drought or low flow conditions. A lack of water affects water-dependent technologies and can result in more expensive generators needing to run in order to meet electric grid demand, resulting in higher electricity prices and a higher cost to operate the grid. A companion study assesses the impact of changes in water availability and air temperatures on power operations by directly derating hydro and thermo-electric generators. In this study we assess the sensitivities and tipping points of water availability compared with higher fuel prices in electricity sector operations. We evaluate the impacts of varying electricity prices by modifying fuel prices for coal and natural gas. We then analyze the difference in simulation results between changes in fuel prices in combination with water availability and air temperature variability. We simulate three fuel price scenarios for a 2010 baseline scenario along with 100 historical and future hydro-climate conditions. We use the PLEXOS electricity production cost model to optimize power system dispatch and cost decisions under each combination of fuel price and water constraint. Some of the metrics evaluated are total production cost, generation type mix, emissions, transmission congestion, and reserve procurement. These metrics give insight to how strained the system is, how much flexibility it still has, and to what extent water resource availability or fuel prices drive changes in the electricity sector operations. This work will provide insights into current electricity operations as well as future cases of increased penetration of variable

A comparison of methods for determining soil water availability in two sites in Panama with similar rainfall but distinct tree communities

Treesearch

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...

Particle water and pH in the Eastern Mediterranean: sources variability and implications for nutrients availability

NASA Astrophysics Data System (ADS)

Nikolaou, P.; Bougiatioti, A.; Stavroulas, I.; Kouvarakis, G.; Nenes, A.; Weber, R.; Kanakidou, M.; Mihalopoulos, N.

2015-10-01

Particle water (LWC) and aerosol pH drive the aerosol phase, heterogeneous chemistry and bioavailability of nutrients that profoundly impact cloud formation, atmospheric composition and atmospheric fluxes of nutrients to ecosystems. Few measurements of in-situ LWC and pH however exist in the published literature. Using concurrent measurements of aerosol chemical composition, cloud condensation nuclei activity and tandem light scattering coefficients, the particle water mass concentrations associated with the aerosol inorganic (Winorg) and organic (Worg) components are determined for measurements conducted at the Finokalia atmospheric observation station in the eastern Mediterranean between August and November 2012. These data are interpreted using the ISORROPIA-II thermodynamic model to predict pH of aerosols originating from the various sources that influence air quality in the region. On average, closure between predicted aerosol water and that determined by comparison of ambient with dry light scattering coefficients was achieved to within 8 % (slope = 0.92, R2 = 0.8, n = 5201 points). Based on the scattering measurements a parameterization is also derived, capable of reproducing the hygroscopic growth factor (f(RH)) within 15 % of the measured values. The highest aerosol water concentrations are observed during nighttime, when relative humidity is highest and the collapse of the boundary layer increases the aerosol concentration. A significant diurnal variability is found for Worg with morning and afternoon average mass concentrations being 10-15 times lower than nighttime concentrations, thus rendering Winorg the main form of particle water during daytime. The average value of total aerosol water was 2.19 ± 1.75 μg m-3, contributing on average up to 33 % of the total submicron mass concentration. Average aerosol water associated with organics, Worg, was equal to 0.56 ± 0.37 μg m-3, thus organics contributed about 27.5 % to the total aerosol water, mostly

Availability of Additional Water for Chiricahua National Monument, Cochise County, Arizona

USGS Publications Warehouse

Johnson, Phillip W.

1962-01-01

The Chiricahua National Monument is in the eastern part of Cochise County, Ariz. The monument is about 35 miles southeast of Wilicox in the north end of the Chiricahua Mountains which border Sulphur Springs Valley on the west. The area is drained by two intermittent washes, one in Bonita and the other in Rhyolite Canyons. Shake Spring is the present source of water for the monument. It ranges in rate of flow from 2 to 12 gpm (gallons per minute) and during dry periods It is not adequate to support the requirements of the monument. Ample water to meet the present and future needs of the Chiricahua National Monument is available from a combination of several sources - undeveloped springs or seeps, capture of runoff out of the canyons, and wells drilled in the alluvium.

Competition-Induced Reductions in Soil Water Availability Reduced Pine Root Extension Rates

Treesearch

K.H. Ludovici; L.A. Morris

1997-01-01

The relationship between soil water availability, root extension, and shoot growth of loblolly pine seedlings (Pinus taeda L.) was evaluated in a rhizotron sand mixture in the absence and presence of crabgrass (Digitaria spp.) competition. Heights and diameters of seedlings grown with crabgrass were reduced 33 and SO%, respectively, compared with...

Influence of geologic setting on ground-water availability in the Lawrenceville area, Gwinnett County, Georgia

USGS Publications Warehouse

Williams, Lester J.; Kath, Randy L.; Crawford, Thomas J.; Chapman, Melinda J.

2005-01-01

Obtaining large quantities of ground water needed for municipal and industrial supply in the Piedmont and Blue Ridge physiographic provinces can be challenging because of the complex geology and the typically low primary permeability of igneous and metamorphic rocks. Areas of enhanced secondary permeability in the bedrock do occur, however, and 'high-yield' wells are not uncommon, particularly where careful site-selection techniques are used prior to test drilling. The U.S. Geological Survey - in cooperation with the City of Lawrenceville, Georgia - conducted this study from 2000 to 2002 to learn more about how different geologic settings influence the availability of ground water in igneous and metamorphic bedrock with the expectation that this knowledge could be used to help identify additional water resources in the area. In compositionally layered-rock settings, wells derive water almost exclusively from lithologically and structurally controlled water-bearing zones formed parallel to foliation and compositional layering. These high-permeability, water-bearing zones - termed foliation-parallel parting systems -combined with high-angle joint systems, are the primary control for the high-yield wells drilled in the Lawrenceville area; yields range from 100 to several hundred gallons per minute (gal/min). Near Lawrenceville, areas with high ground-water yield are present in sequences of amphibolite, biotite gneiss, and button schist where the structural attitude of the rocks is gently dipping, in areas characterized by abundant jointing, and in topographic settings with a continuous source of recharge along these structures. In massive-rock settings, wells derive water mostly from joint systems, although foliation-parallel parting systems also may be important. Wells deriving water primarily from steeply-dipping joint systems typically have low yields ranging from 1 to 5 gal/min. Joint systems in massive-rock settings can be identified and characterized by using

Water-quality assessment of the Trinity River Basin, Texas - Analysis of available information on nutrients and suspended sediment, 1974-91

USGS Publications Warehouse

Van Metre, Peter C.; Reutter, David C.

1995-01-01

Only limited suspended-sediment data were available. Four sites had daily sediment-discharge records for three or more water years (October 1 to September 30) between 1974 and 1985. An additional three sites had periodic measurements of suspended-sediment concentrations. There are differences in concentrations and yields among sites; however, the limited amount of data precludes developing statistical or cause-and-effect relations with environmental factors such as land use, soil, and geology. Data are sufficient, and the relation is pronounced enough, to indicate trapping of suspended sediment by Livingston Reservoir.

High water availability increases the negative impact of a native hemiparasite on its non-native host.

PubMed

Cirocco, Robert M; Facelli, José M; Watling, Jennifer R

2016-03-01

Environmental factors alter the impacts of parasitic plants on their hosts. However, there have been no controlled studies on how water availability modulates stem hemiparasites' effects on hosts. A glasshouse experiment was conducted to investigate the association between the Australian native stem hemiparasite Cassytha pubescens and the introduced host Ulex europaeus under high (HW) and low (LW) water supply. Cassytha pubescens had a significant, negative effect on the total biomass of U. europaeus, which was more severe in HW than LW. Regardless of watering treatment, infection significantly decreased shoot and root biomass, nodule biomass, nodule biomass per unit root biomass, F v/F m, and nitrogen concentration of U. europaeus. Host spine sodium concentration significantly increased in response to infection in LW but not HW conditions. Host water potential was significantly higher in HW than in LW, which may have allowed the parasite to maintain higher stomatal conductances in HW. In support of this, the δ(13)C of the parasite was significantly lower in HW than in LW (and significantly higher than the host). C. pubescens also had significantly higher F v/F m and 66% higher biomass per unit host in the HW compared with the LW treatment. The data suggest that the enhanced performance of C. pubescens in HW resulted in higher parasite growth rates and thus a larger demand for resources from the host, leading to poorer host performance in HW compared with LW. C. pubescens should more negatively affect U. europaeus growth under wet conditions rather than under dry conditions in the field. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology.

Estimated water use and availability in the Pawcatuck Basin, southern Rhode Island and southeastern Connecticut, 1995-99

USGS Publications Warehouse

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

Analysis of River Water Quality and its influencing factors for the Effective Management of Water Environment

NASA Astrophysics Data System (ADS)

Shrestha, G.; Sadohara, S.; Yoshida, S.; Yuichi, S.

2011-12-01

In Japan, remarkable improvements in water quality have been observed over recent years because of regulations imposed on industrial wastewater and development of sewerage system. However, pollution loads from agricultural lands are still high and coverage ratio of sewerage system is still low in small and medium cities. In present context, nonpoint source pollution such as runoff from unsewered developments, urban and agricultural runoffs could be main water quality impacting factors. Further, atmospheric nitrogen (N) is the complex nonpoint source than can seriously affect river water environment. This study was undertaken to spatially investigate the present status of river water quality of Hadano Basin located in Kanagawa Prefecture, Japan. Water quality of six rivers was investigated and its relationship with nonpoint pollution sources was analyzed. This study, with inclusion of ground water circulation and atmospheric N, can be effectively employed for water quality management of other watersheds also, both with and without influence of ground water circulation. Hence, as a research area of this study, it is significant in terms of water quality management. Total nitrogen (TN) was found consistently higher in urbanized basins indicating that atmospheric N might be influencing TN of river water. Ground water circulation influenced both water quality and quantity. In downstream basins of Muro and Kuzuha rivers, Chemical oxygen demand (COD) and total phosphorus (TP) were diluted by ground water inflow. In Mizunashi River and the upstream of Kuzuha River, surface water infiltrated to the subsurface due to higher river bed permeability. Influencing factors considered in the analysis were unsewered population, agricultural land, urban area, forest and atmospheric N. COD and TP showed good correlation with unsewered population and agricultural land. While TN had good correlation with atmospheric N deposition. Multiple regression analysis between water quality

Use of Atmospheric Budget to Reduce Uncertainty in Estimated Water Availability over South Asia from Different Reanalyses

NASA Astrophysics Data System (ADS)

Sebastian, Dawn Emil; Pathak, Amey; Ghosh, Subimal

2016-07-01

Disagreements across different reanalyses over South Asia result into uncertainty in assessment of water availability, which is computed as the difference between Precipitation and Evapotranspiration (P-E). Here, we compute P-E directly from atmospheric budget with divergence of moisture flux for different reanalyses and find improved correlation with observed values of P-E, acquired from station and satellite data. We also find reduced closure terms for water cycle computed with atmospheric budget, analysed over South Asian landmass, when compared to that obtained with individual values of P and E. The P-E value derived with atmospheric budget is more consistent with energy budget, when we use top-of-atmosphere radiation for the same. For analysing water cycle, we use runoff from Global Land Data Assimilation System, and water storage from Gravity Recovery and Climate Experiment. We find improvements in agreements across different reanalyses, in terms of inter-annual cross correlation when atmospheric budget is used to estimate P-E and hence, emphasize to use the same for estimations of water availability in South Asia to reduce uncertainty. Our results on water availability with reduced uncertainty over highly populated monsoon driven South Asia will be useful for water management and agricultural decision making.

Use of Atmospheric Budget to Reduce Uncertainty in Estimated Water Availability over South Asia from Different Reanalyses.

PubMed

Sebastian, Dawn Emil; Pathak, Amey; Ghosh, Subimal

2016-07-08

Disagreements across different reanalyses over South Asia result into uncertainty in assessment of water availability, which is computed as the difference between Precipitation and Evapotranspiration (P-E). Here, we compute P-E directly from atmospheric budget with divergence of moisture flux for different reanalyses and find improved correlation with observed values of P-E, acquired from station and satellite data. We also find reduced closure terms for water cycle computed with atmospheric budget, analysed over South Asian landmass, when compared to that obtained with individual values of P and E. The P-E value derived with atmospheric budget is more consistent with energy budget, when we use top-of-atmosphere radiation for the same. For analysing water cycle, we use runoff from Global Land Data Assimilation System, and water storage from Gravity Recovery and Climate Experiment. We find improvements in agreements across different reanalyses, in terms of inter-annual cross correlation when atmospheric budget is used to estimate P-E and hence, emphasize to use the same for estimations of water availability in South Asia to reduce uncertainty. Our results on water availability with reduced uncertainty over highly populated monsoon driven South Asia will be useful for water management and agricultural decision making.

Use of Atmospheric Budget to Reduce Uncertainty in Estimated Water Availability over South Asia from Different Reanalyses

PubMed Central

Sebastian, Dawn Emil; Pathak, Amey; Ghosh, Subimal

2016-01-01

Disagreements across different reanalyses over South Asia result into uncertainty in assessment of water availability, which is computed as the difference between Precipitation and Evapotranspiration (P–E). Here, we compute P–E directly from atmospheric budget with divergence of moisture flux for different reanalyses and find improved correlation with observed values of P–E, acquired from station and satellite data. We also find reduced closure terms for water cycle computed with atmospheric budget, analysed over South Asian landmass, when compared to that obtained with individual values of P and E. The P–E value derived with atmospheric budget is more consistent with energy budget, when we use top-of-atmosphere radiation for the same. For analysing water cycle, we use runoff from Global Land Data Assimilation System, and water storage from Gravity Recovery and Climate Experiment. We find improvements in agreements across different reanalyses, in terms of inter-annual cross correlation when atmospheric budget is used to estimate P–E and hence, emphasize to use the same for estimations of water availability in South Asia to reduce uncertainty. Our results on water availability with reduced uncertainty over highly populated monsoon driven South Asia will be useful for water management and agricultural decision making. PMID:27388837

Enhancing capacitive deionization technology as an effective method for water treatment using commercially available graphene.

PubMed

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.

Availability and quality of ground water, southern Ute Indian Reservation, southwestern Colorado

USGS Publications Warehouse

Brogden, Robert E.; Hutchinson, E. Carter; Hillier, Donald E.

1979-01-01

Population growth and the potential development of subsurface mineral resources have increased the need for information on the availability and quality of ground water on the Southern Ute Indian Reservation. The U.S. Geological Survey, in cooperation with the Southern Ute Tribal Council, the Four Corners Regional Planning Commission, and the U.S. Bureau of Indian Affairs, conducted a study during 1974-76 to assess the ground-water resources of the reservation. Water occurs in aquifers in the Dakota Sandstone, Mancos Shale, Mesaverde Group, Lewis Shale, Pictured Cliffs Sandstone, Fruitland Formation, Kirtland Shale, Animas and San Jose Formations, and terrace and flood-plain deposits. Well yields from sandstone and shale aquifers are small, generally in the range from 1 to 10 gallons per minute with maximum reported yields of 75 gallons per minute. Well yields from terrace deposits generally range from 5 to 10 gallons per minute with maximum yields of 50 gallons per minute. Well yields from flood-plain deposits are as much as 25 gallons per minute but average 10 gallons per minute. Water quality in aquifers depends in part on rock type. Water from sandstone, terrace, and flood-plain aquifers is predominantly a calcium bicarbonate type, whereas water from shale aquifers is predominantly a sodium bicarbonate type. Water from rocks containing interbeds of coal or carbonaceous shales may be either a calcium or sodium sulfate type. Dissolved-solids concentrations of ground water ranged from 115 to 7,130 milligrams per liter. Water from bedrock aquifers is the most mineralized, while water from terrace and flood-plain aquifers is the least mineralized. In many water samples collected from bedrock, terrace, and flood-plain aquifers, the concentrations of arsenic, chloride, dissolved solids, fluoride, iron, manganese, nitrate, selenium, and sulfate exceeded U.S. Public Health Service (1962) recommended limits for drinking water. Selenium in the ground water in excess of U

Combined impacts of climate and socio-economic scenarios on irrigation water availability for a dry Mediterranean reservoir.

PubMed

Nunes, João Pedro; Jacinto, Rita; Keizer, Jan Jacob

2017-04-15

The impacts of climate and associated socio-economic changes on water availability, including supply and demand, quality, and storage volume, were evaluated for the Vale do Gaio reservoir in southern Portugal, located in a dry Mediterranean climate and already under drought stress. The SWAT model was applied with 6 scenarios for 2071-2100, involving two storylines (A1B and B1) with individual changes in climate (-9% rainfall, increasing in winter by +28 to +30%), socio-economic conditions (an increase in irrigation demand by 11%, and a replacement of cereals and pastures by sunflower), and a combination of both. Most future scenarios resulted in lower water availability, due to lower supply (-19 to -27%) combined with higher irrigation demand (+3 to +21%). This resulted in more years with limited irrigation supplies (presently: 28%; scenarios: 37 to 43%), although limitations were mitigated by lower losses to excess discharge. Land-use changes also decreased quality by increasing P concentrations (+29 to +93%). Impacts were more severe in scenario A1B than in B1, and in combined changes than in climate or socio-economic changes only. Water availability was resilient to climate change, as impacts led only to a moderate aggravation of present-day conditions. Lower future water availability could be addressed by supply and demand management strategies and, in the most extreme scenario, by water transfers from regional water reserves; water quality issues could be addressed through land-use policies. Results also highlighted the importance of taking the characteristics of water supply systems into account when designing adaptation measures for future changes. Copyright © 2017 Elsevier B.V. All rights reserved.

A Versatile Phenotyping System and Analytics Platform Reveals Diverse Temporal Responses to Water Availability in Setaria.

PubMed

Fahlgren, Noah; Feldman, Maximilian; Gehan, Malia A; Wilson, Melinda S; Shyu, Christine; Bryant, Douglas W; Hill, Steven T; McEntee, Colton J; Warnasooriya, Sankalpi N; Kumar, Indrajit; Ficor, Tracy; Turnipseed, Stephanie; Gilbert, Kerrigan B; Brutnell, Thomas P; Carrington, James C; Mockler, Todd C; Baxter, Ivan

2015-10-05

Phenotyping has become the rate-limiting step in using large-scale genomic data to understand and improve agricultural crops. Here, the Bellwether Phenotyping Platform for controlled-environment plant growth and automated multimodal phenotyping is described. The system has capacity for 1140 plants, which pass daily through stations to record fluorescence, near-infrared, and visible images. Plant Computer Vision (PlantCV) was developed as open-source, hardware platform-independent software for quantitative image analysis. In a 4-week experiment, wild Setaria viridis and domesticated Setaria italica had fundamentally different temporal responses to water availability. While both lines produced similar levels of biomass under limited water conditions, Setaria viridis maintained the same water-use efficiency under water replete conditions, while Setaria italica shifted to less efficient growth. Overall, the Bellwether Phenotyping Platform and PlantCV software detected significant effects of genotype and environment on height, biomass, water-use efficiency, color, plant architecture, and tissue water status traits. All ∼ 79,000 images acquired during the course of the experiment are publicly available. Copyright © 2015 The Author. Published by Elsevier Inc. All rights reserved.

Influence of landscape heterogeneity on water available to tropical forests in an Amazonian catchment and implications for modeling drought response

NASA Astrophysics Data System (ADS)

Fang, Yilin; Leung, L. Ruby; Duan, Zhuoran; Wigmosta, Mark S.; Maxwell, Reed M.; Chambers, Jeffrey Q.; Tomasella, Javier

2017-08-01

The Amazon basin has experienced periodic droughts in the past, and intense and frequent droughts are predicted in the future. Landscape heterogeneity could play an important role in how tropical forests respond to drought by influencing water available to plants. Using the one-dimensional ACME Land Model and the three-dimensional ParFlow variably saturated flow model, numerical experiments were performed for a catchment in central Amazon to elucidate processes that influence water available for plant use and provide insights for improving Earth system models. Results from ParFlow show that topography has a dominant influence on groundwater table and runoff through lateral flow. Without any representations of lateral processes, ALM simulates very different seasonal variations in groundwater table and runoff compared to ParFlow even if it is able to reproduce the long-term spatial average groundwater table of ParFlow through simple parameter calibration. In the ParFlow simulations, even in the plateau with much deeper water table depth during the dry season in the drought year of 2005, plant transpiration is not water stressed as the soil saturation is still sufficient for the stomata to be fully open based on the empirical wilting formulation in the models. This finding is insensitive to uncertainty in atmospheric forcing and soil parameters, but the empirical wilting formulation is an important factor that should be addressed using observations and modeling of coupled plant hydraulics-soil hydrology processes in future studies. The results could be applicable to other catchments in the Amazon basin with similar seasonal variability and hydrologic regimes.

Drinking water intake of grazing steers: the role of environmental factors controlling canopy wetness.

PubMed

Sun, L Z; Auerswald, K; Wenzel, R; Schnyder, H

2014-01-01

Cattle obtain water primarily from the moisture in their feed and from drinking water. On pasture, the moisture content of the diet is influenced by plant tissue water (internal water) and surface moisture (external water), which may include dew, guttation, and intercepted rain, that influence the drinking water requirement. This study investigated the relationship between daily drinking water intake (DWI, L/d) of steers on pasture (19 steers with mean initial BW of approximately 400 kg) and soil and weather factors that are known to affect plant water status (dry matter content) and surface moisture formation and persistence. Daily records of weather conditions and DWI were obtained during 2 grazing seasons with contrasting spring, summer, and autumn rainfall patterns. Plant available water in the soil (PAW, mm) was modeled from actual and potential evapotranspiration and the water-holding capacity of the soil. The DWI averaged over the herd varied among days from 0 to 29 L/d (grazing season mean 9.8 L/d). The DWI on both dry (<0.2 mm rainfall on the corresponding and previous days) and wet (>2 mm) days increased with increasing temperature (mean, maximum, and minimum), sunshine hours, and global radiation and decreasing relative humidity, and the slopes and coefficients of determination were generally greater for wet days. Wind reduced DWI on wet days but had no effect on dry days. The DWI was reduced by up to 4.4 L/d on wet days compared to dry days, but DWI did not correlate with rainfall amount. Increasing PAW decreased DWI by up to >10 L/d on both dry and wet days. These results are all consistent with environmental effects on the water status (dry matter content) of pasture vegetation and canopy surface moisture, the associated effects on grazing-related water intake, and the corresponding balancing changes of DWI. Using the observed relationships with environmental factors, we derived a new model predicting DWI for any soil moisture condition, for both wet

Factors affecting the accumulation of phytoplankton biomass in Irish estuaries and nearshore coastal waters: A conceptual model

NASA Astrophysics Data System (ADS)

O'Boyle, Shane; Wilkes, Robert; McDermott, Georgina; Ní Longphuirt, Sorcha; Murray, Clare

2015-03-01

A multivariate statistical approach was used to investigate the response of phytoplankton in Irish estuaries and nearshore coastal waters to nutrient enrichment and to examine the factors which modulate this response. The analysis suggests that while many estuaries are nutrient-enriched, relatively few display phytoplankton-related symptoms of eutrophication as the response to nutrients is primarily affected by insufficient retention time, in some by inadequate light availability, and only rarely by both factors acting together. Nearshore coastal waters are nitrogen (N) and silica (Si) limited in summer, but in some nearshore waters along the south coast, where N is elevated, phosphorus (P) is potentially limiting. The reduction in P loadings to estuarine waters is likely to lead to an improvement in the eutrophication status of these mainly P-limited waters. The disproportionate reduction in loadings of P compared to N (52% versus 24%, since the early 1990s), and the potential weakening of the estuarine N filter, as eutrophication symptoms lessen, may result in the downstream movement of nitrogen to N-limited coastal waters. These findings support the view that an integrated dual-nutrient reduction strategy is required to address eutrophication along the freshwater-marine continuum. The outcome of the analysis is a conceptual model which is of direct value and use to water managers in determining the relative susceptibility of these waters to nutrient enrichment. This understanding can in turn be used to develop informed programmes of measures which are targeted and ultimately cost effective.

A Strategy for Federal Science and Technology to Support Water Availability and Quality in the United States

DTIC Science & Technology

2007-09-01

Subcommittee on Water Availability and Quality Microbial source tracking to identify the source of fecal contamination Many of the Nation’s resource...water- quality health standards. In addition, identi- fication of fecal sources is relevant to source-water protection programs and to the development...estuaries, snowpack, and soil . • Develop sensors and systems to measure water quality inexpensively in real time. Develop innovative water-use technologies

75 FR 52523 - Southern Nevada Water Authority; Notice of Availability of Environmental Assessment

Federal Register 2010, 2011, 2012, 2013, 2014

2010-08-26

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Project No. 13569-001-NV] Southern Nevada Water Authority; Notice of Availability of Environmental Assessment August 19, 2010. In accordance with the National Environmental Policy Act of 1969 and the Federal Energy Regulatory Commission's...

75 FR 8698 - Clean Water Act Section 303(d): Availability of Ten Total Maximum Daily Loads (TMDLs) in Louisiana

Federal Register 2010, 2011, 2012, 2013, 2014

2010-02-25

... ENVIRONMENTAL PROTECTION AGENCY [FRL-9118-5] Clean Water Act Section 303(d): Availability of Ten...: Notice of availability. SUMMARY: This notice announces the availability for comment on the administrative... Smith, Environmental Protection Specialist, Water Quality Protection Division, U.S. Environmental...

76 FR 80366 - Clean Water Act Section 303(d): Availability of One Total Maximum Daily Load (TMDL) in Louisiana

Federal Register 2010, 2011, 2012, 2013, 2014

2011-12-23

... ENVIRONMENTAL PROTECTION AGENCY [FRL-9610-6] Clean Water Act Section 303(d): Availability of One...: Notice of availability. SUMMARY: This notice announces the availability for comment on the administrative..., Environmental Protection Specialist, Water Quality Protection Division, U.S. Environmental Protection Agency...

NASA Land Information System (LIS) Water Availability to Support Reclamation ET Estimation

NASA Technical Reports Server (NTRS)

Toll, David; Arsenault, Kristi; Pinheiro, Ana; Peters-Lidard, Christa; Houser, Paul; Kumar, Sujay; Engman, Ted; Nigro, Joe; Triggs, Jonathan

2005-01-01

The U.S. Bureau of Reclamation identified the remote sensing of evapotranspiration (ET) as an important water flux for study and designated a test site in the Lower Colorado River basin. A consortium of groups will work together with the goal to develop more accurate and cost effective techniques using the enhanced spatial and temporal coverage afforded by remote sensing. ET is a critical water loss flux where improved estimation should lead to better management of Reclamation responsibilities. There are several areas where NASA satellite and modeling data may be useful to meet Reclamation's objectives for improved ET estimation. In this paper we outline one possible contribution to use NASA's data integration capability of the Land Information System (LIS) to provide a merger of observational (in situ and satellite) with physical process models to provide estimates of ET and other water availability outputs (e.g., runoff, soil moisture) retrospectively, in near real-time, and also providing short-term predictions.

Energy Factor Analysis for Gas Heat Pump Water Heaters

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

Gluesenkamp, Kyle R

2016-01-01

Gas heat pump water heaters (HPWHs) can improve water heating efficiency with zero GWP and zero ODP working fluids. The energy factor (EF) of a gas HPWH is sensitive to several factors. In this work, expressions are derived for EF of gas HPWHs, as a function of heat pump cycle COP, tank heat losses, burner efficiency, electrical draw, and effectiveness of supplemental heat exchangers. The expressions are used to investigate the sensitivity of EF to each parameter. EF is evaluated on a site energy basis (as used by the US DOE for rating water heater EF), and a primary energy-basismore » energy factor (PEF) is also defined and included. Typical ranges of values for the six parameters are given. For gas HPWHs, using typical ranges for component performance, EF will be 59 80% of the heat pump cycle thermal COP (for example, a COP of 1.60 may result in an EF of 0.94 1.28). Most of the reduction in COP is due to burner efficiency and tank heat losses. Gas-fired HPWHs are theoretically be capable of an EF of up to 1.7 (PEF of 1.6); while an EF of 1.1 1.3 (PEF of 1.0 1.1) is expected from an early market entry.« less

The quality of our Nation's waters: factors affecting public-supply-well vulnerability to contamination: understanding observed water quality and anticipating future water quality

USGS Publications Warehouse

Eberts, Sandra M.; Thomas, Mary Ann; Jagucki, Martha L.

2013-01-01

As part of the U.S. Geological Survey National Water-Quality Assessment (NAWQA) Program, a study was conducted from 2001 to 2011 to shed light on factors that affect the vulnerability of water from public-supply wells to contamination (referred to hereafter as “public-supply-well vulnerability”). The study was designed as a follow-up to earlier NAWQA studies that found mixtures of contaminants at low concentrations in groundwater near the water table in urban areas across the Nation and, less frequently, in deeper groundwater typically used for public supply. Beside the factors affecting public-supply-well vulnerability to contamination, this circular describes measures that can be used to determine which factor (or factors) plays a dominant role at an individual public-supply well. Case-study examples are used throughout to show how such information can be used to improve water quality. In general, the vulnerability of the water from public-supply wells to contamination is a function of contaminant input within the area that contributes water to a well, the mobility and persistence of a contaminant once released to the groundwater, and the ease of groundwater and contaminant movement from the point of recharge to the open interval of a well. The following measures described in this circular are particularly useful for indicating which contaminants in an aquifer might reach an individual public-supply well and when, how, and at what concentration they might arrive: * Sources of recharge—Information on the sources of recharge for a well provides insight into contaminants that might enter the aquifer with the recharge water and potentially reach the well. * Geochemical conditions—Information on the geochemical conditions encountered by groundwater traveling to a well provides insight into contaminants that might persist in the water all the way to the well. * Groundwater-age mixtures—Information on the ages of the different waters that mix in a well

Map showing general availability of ground water in the Alton-Kolob coal-fields area, Utah

USGS Publications Warehouse

Price, Don

1982-01-01

This is one of a series of maps that describes the geology and related natural resources of the Alton-Kolob coal-fields area, Utah. Shown on this map is the general availability of ground water as indicated by potential yields of individual wells and expected depth to water in wells. Most data used to compile this map were collected by the U.S. Geological Survey in cooperation with the Utah Department of Natural Resources Division of Water Rights. Other sources of data included the U.S. Geological Survey 7½- and 15-minute topographic quadrangle maps, unpublished reports of field evaluations of potential shock-watering sites by U.S. Geological Survey personnel, and the geologic map of Utah (Stokes, 1964).This map is very generalized and is intended chiefly for planning purposes. It should be used with discretion. For more detailed information about the availability of ground water in various parts of the map area the reader is referred to the following reports: Thomas and Taylor (1946); Marine (1963); Sandberg (1963, 1966); Carpenter, Robinson, and Bjorklund (1964, 1967); Feltis (1966); Goode (1964, 1966); Cordova, Sandberg, and McConkie (1972); Cordova (1978, 1981); and Bjorklund, Sumison, and Sandberg (1977, 1978). For a general description of the chemical quality of ground water in the Alton-Kolob coal-fields area the reader is referred to Price (1981).

Map showing general availability of ground water in the Kaiparowits coal-basin area, Utah

USGS Publications Warehouse

Price, Don

1977-01-01

This is one of a series of maps that describe the geology and related natural resources in the Kaiparowits coal-basin area. This map is based partly on records of water wells, springs, and coal and petroleum exploration holes, partly on unpublished reports of field evaluations of prospective stock-water well sites by personnel of the U.S. Geological Survey, and partly on a 6-day field reconnaissance by the writer in parts of the mapped area.Most of the data used to compile this map were collected by the U.S. Geological Survey in cooperation with State, local, and other Federal agencies. Published sources of data included Phoenix (1963), Iorns, Hembree, and Phoenix (1964), Cooley (1965), Feltis (1966), Goode (1966, 1969), and the final environmental impact statement for the proposed Kaiparowits power project (U.S. Bureau of Land Management, 1976).Few data about the availability or depth of ground water could be obtained for large areas in the Kaiparowits coal basin. In those areas, expected yields of individual wells are inferred from the geology as compiled by Stokes (1964) and Hackman and Wyant (1973), and depths of ground water in wells are inferred largely from the local topography.El Paso Natural Gas Co., Resources Co., Kaiser Engineers, and Southern California Edison Co. provided specific information regarding the availability and depth of ground water in their exploratory holes on the Kaiparowits Plateau. The cooperation of those firms is gratefully acknowledged.

Seedling Biomass Partition and Water Use Efficiency of Switchgrass and Milkvetch in Monocultures and Mixtures in Response to Various Water Availabilities

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.

Precipitation v. River Discharge Controls on Water Availability to Riparian Trees in the Rhône River Delta

NASA Astrophysics Data System (ADS)

Singer, M. B.; Sargeant, C. I.; Vallet-Coulomb, C.; Evans, C.; Bates, C. R.

2014-12-01

Water availability to riparian trees in lowlands is controlled through precipitation and its infiltration into floodplain soils, and through river discharge additions to the hyporheic water table. The relative contributions of both water sources to the root zone within river floodplains vary through time, depending on climatic fluctuations. There is currently limited understanding of how climatic fluctuations are expressed at local scales, especially in 'critical zone' hydrology, which is fundamental to the health and sustainability of riparian forest ecosystems. This knowledge is particularly important in water-stressed Mediterranean climate systems, considering climatic trends and projections toward hotter and drier growing seasons, which have the potential to dramatically reduce water availability to riparian forests. Our aim is to identify and quantify the relative contributions of hyporheic (discharge) water v. infiltrated precipitation to water uptake by riparian Mediterranean trees for several distinct hydrologic years, selected to isolate contrasts in water availability from these sources. Our approach includes isotopic analyses of water and tree-ring cellulose, mechanistic modeling of water uptake and wood production, and physically based modeling of subsurface hydrology. We utilize an extensive database of oxygen isotope (δ18O) measurements in surface water and precipitation alongside recent measurements of δ18O in groundwater and soil water and in tree-ring cellulose. We use a mechanistic model to back-calculate source water δ18O based on δ18O in cellulose and climate data. Finally, we test our results via 1-D hydrologic modeling of precipitation infiltration and water table rise and fall. These steps enable us to interpret hydrologic cycle variability within the 'critical zone' and their potential impact on riparian trees.

Distribution and availability of mercury and methylmercury in different waters from the Rio Madeira Basin, Amazon.

PubMed

Vieira, Miguel; Bernardi, José V E; Dórea, José G; Rocha, Bruno C P; Ribeiro, Romulo; Zara, Luis F

2018-04-01

Waters from the Amazon Basin have distinct physicochemical characteristics that can be optically classified as "black", "clear" and "white". We studied the distribution of total-Hg (THg) and methyl-Hg (MeHg) in these waters and respective suspended solids, sediment, phytoplankton, zooplankton, and benthic macroinvertebrates (BM) in the Madeira River Basin. Compared with the other types of water, the more acidic "black" kind had the highest THg and MeHg concentrations. The trend (black > clear > white) occurred for the concentrations of THg and MeHg in sediments and in the biotic compartment (plankton, macroinvertebrates). Organic Hg accounted for a small percentage (0.6-0.4%) of the THg in sediments but was highest in water (17-15%). For plankton and BM, the biota sediment accumulation factor (BSAFs) of MeHg (53-125) were greater than those of THg (4.5-15); however, the BSAF trend according to water type (black > clear > white) was only significant for MeHg. Sediment THg is correlated with all forms of Hg in biotic and abiotic matrices. The results indicate that water acidity in the Amazon is an important chemical characteristic in assessing Hg contamination of sediments and bioaccumulation in the aquatic food web. The differences in the BSAFs between THg and MeHg support the use of this factor for evaluating the bioaccumulation potential of sediment-bound Hg. The results add information critical to assessing environmental and health risks related to Hg methylation and potential fish-MeHg contamination, especially in tropical aquatic environments. Copyright © 2018 Elsevier Ltd. All rights reserved.

Identification of glacial meltwater runoff in a karstic environment and its implication for present and future water availability

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.

Altered resource availability and the population dynamics of tree species in Amazonian secondary forests.

PubMed

Fortini, Lucas Berio; Bruna, Emilio M; Zarin, Daniel J; Vasconcelos, Steel S; Miranda, Izildinha S

2010-04-01

Despite research demonstrating that water and nutrient availability exert strong effects on multiple ecosystem processes in tropical forests, little is known about the effect of these factors on the demography and population dynamics of tropical trees. Over the course of 5 years, we monitored two common Amazonian secondary forest species-Lacistema pubescens and Myrcia sylvatica-in dry-season irrigation, litter-removal and control plots. We then evaluated the effects of altered water and nutrient availability on population demography and dynamics using matrix models and life table response experiments. Our results show that despite prolonged experimental manipulation of water and nutrient availability, there were nearly no consistent and unidirectional treatment effects on the demography of either species. The patterns and significance of observed treatment effects were largely dependent on cross-year variability not related to rainfall patterns, and disappeared once we pooled data across years. Furthermore, most of these transient treatment effects had little effect on population growth rates. Our results suggest that despite major experimental manipulations of water and nutrient availability-factors considered critical to the ecology of tropical pioneer tree species-autogenic light limitation appears to be the primary regulator of tree demography at early/mid successional stages. Indeed, the effects of light availability may completely override those of other factors thought to influence the successional development of Amazonian secondary forests.

High sensitivity of broadleaf trees to water availability in northeastern United States

NASA Astrophysics Data System (ADS)

Levesque, Mathieu; Andreu-Hayles, Laia; Pederson, Neil

2016-04-01

Broadleaf dominated forests of eastern US cover more than one million km2 and provide ecosystem services to millions of people. High species diversity and a varied sensitivity to drought make it uncertain whether these forests will be carbon sinks or sources under climate change. Ongoing climate change, increased in atmospheric CO2 concentration (ca) and strong reductions in acidic depositions are expected to alter growth and gas exchange of trees, and ultimately forest productivity. Still, the magnitude of these effects is unclear. A better comprehension of the species-specific responses to environmental changes will better inform models and managers on the vulnerability and resiliency of these forests. Here, we combined tree-ring width data with δ13C and δ18O measurements to investigate growth and physiological responses of red oak (Quercus rubra L.) and tulip poplar (Liriodendron tulipifera L.) in northeastern US to changes in water availability, ca and acidic depositions for the period 1950-2014. Based on structural equation modeling approaches, we found that summer water availability (June-August) is the main environmental variable driving growth, water-use efficiency and δ18O of broadleaf trees whereas ca and acidic depositions have little effects. This high sensitivity to moisture availability was also supported by the very strong correlations found between summer vapor pressure deficit (VPD) and tree-ring δ13C (r = 0.67 and 0.71), and δ18O series (r = 0.62 and 0.72), for red oak and tulip poplar, respectively. In contrast, tree-ring width was less sensitive to summer VPD (r = -0.44 and-0.31). Since the mid 1980s, pluvial conditions occurring in northeastern US have increased stomatal conductance, carbon uptake, and growth of both species. Further, the strong spatial field correlations found between the tree-ring δ13C and δ18O and summer VPD indicate a greater sensitivity of eastern US broadleaf forests to moisture availability than previously known

Factors affecting the availability and use of hemodialysis facilities.

PubMed

Cleary, P D; Schlesinger, M; Blumenthal, D

1991-01-01

This article describes factors related to the geographic distribution of hemodialysis facilities and the relationship between availability and use. Such facilities tend to be concentrated in the same types of areas as other medical resources, and the number of medical specialists in an area is related to the rate of treatment for renal diseases. The proportion of treatment stations in an area owned by for-profit organizations is not related to the total treatment rate, but the market share of for-profit facilities is positively related to in-center treatment and negatively related to home treatment.

75 FR 20351 - Clean Water Act Section 303(d): Availability of One Total Maximum Daily Load (TMDL) in Arkansas

Federal Register 2010, 2011, 2012, 2013, 2014

2010-04-19

... ENVIRONMENTAL PROTECTION AGENCY [FRL-9139-5] Clean Water Act Section 303(d): Availability of One...: Notice of availability. SUMMARY: This notice announces the availability of the administrative record file... in the State of Arkansas under Section 303(d) of the Clean Water Act (CWA). This TMDL was completed...

Increasing water availability during afterschool snack: evidence, strategies, and partnerships from a group randomized trial.

PubMed

Giles, Catherine M; Kenney, Erica L; Gortmaker, Steven L; Lee, Rebekka M; Thayer, Julie C; Mont-Ferguson, Helen; Cradock, Angie L

2012-09-01

Providing drinking water to U.S. children during school meals is a recommended health promotion strategy and part of national nutrition policy. Urban school systems have struggled with providing drinking water to children, and little is known about how to ensure that water is served, particularly in afterschool settings. To assess the effectiveness of an intervention designed to promote water as the beverage of choice in afterschool programs. The Out of School Nutrition and Physical Activity Initiative (OSNAP) used a community-based collaboration and low-cost strategies to provide water after school. A group RCT was used to evaluate the intervention. Data were collected in 2010-2011 and analyzed in 2011. Twenty afterschool programs in Boston were randomized to intervention or control (delayed intervention). Intervention sites participated in learning collaboratives focused on policy and environmental changes to increase healthy eating, drinking, and physical activity opportunities during afterschool time (materials available at www.osnap.org). Collaboration between Boston Public Schools Food and Nutrition Services, afterschool staff, and researchers established water-delivery systems to ensure children were served water during snack time. Average ounces of water served to children per day was recorded by direct observation at each program at baseline and 6-month follow-up over 5 consecutive school days. Secondary measures directly observed included ounces of other beverages served, other snack components, and water-delivery system. Participation in the intervention was associated with an increased average volume of water served (+3.6 ounces/day; p=0.01) during snack. On average, the intervention led to a daily decrease of 60.9 kcals from beverages served during snack (p=0.03). This study indicates the OSNAP intervention, including strategies to overcome structural barriers and collaboration with key actors, can increase offerings of water during afterschool snack

Understorey productivity in temperate grassy woodland responds to soil water availability but not to elevated [CO2 ].

PubMed

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.

Water-Related Power Plant Curtailments: An Overview of Incidents and Contributing Factors

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

McCall, James; Macknick, Jordan; Macknick, Jordan

Water temperatures and water availability can affect the reliable operations of power plants in the United States. Data on water-related impacts on the energy sector are not consolidated and are reported by multiple agencies. This study provides an overview of historical incidents where water resources have affected power plant operations, discusses the various data sources providing information, and creates a publicly available and open access database that contains consolidated information about water-related power plant curtailment and shut-down incidents. Power plants can be affected by water resources if incoming water temperatures are too high, water discharge temperatures are too high, ormore » if there is not enough water available to operate. Changes in climate have the potential to exacerbate uncertainty over water resource availability and temperature. Power plant impacts from water resources include curtailment of generation, plant shut-downs, and requests for regulatory variances. In addition, many power plants have developed adaptation approaches to reducing the potential risks of water-related issues by investing in new technologies or developing and implementing plans to undertake during droughts or heatwaves. This study identifies 42 incidents of water-related power plant issues from 2000-2015, drawing from a variety of different datasets. These incidents occur throughout the U.S., and affect coal and nuclear plants that use once-through, recirculating, and pond cooling systems. In addition, water temperature violations reported to the Environmental Protection Agency are also considered, with 35 temperature violations noted from 2012-2015. In addition to providing some background information on incidents, this effort has also created an open access database on the Open Energy Information platform that contains information about water-related power plant issues that can be updated by users.« less

Aerial and surface rivers: downwind impacts on water availability from land use changes in Amazonia

NASA Astrophysics Data System (ADS)

Weng, Wei; Luedeke, Matthias K. B.; Zemp, Delphine C.; Lakes, Tobia; Kropp, Juergen P.

2018-02-01

The abundant evapotranspiration provided by the Amazon forests is an important component of the hydrological cycle, both regionally and globally. Since the last century, deforestation and expanding agricultural activities have been changing the ecosystem and its provision of moisture to the atmosphere. However, it remains uncertain how the ongoing land use change will influence rainfall, runoff, and water availability as findings from previous studies differ. Using moisture tracking experiments based on observational data, we provide a spatially detailed analysis recognizing potential teleconnection between source and sink regions of atmospheric moisture. We apply land use scenarios in upwind moisture sources and quantify the corresponding rainfall and runoff changes in downwind moisture sinks. We find spatially varying responses of water regimes to land use changes, which may explain the diverse results from previous studies. Parts of the Peruvian Amazon and western Bolivia are identified as the sink areas most sensitive to land use change in the Amazon and we highlight the current water stress by Amazonian land use change on these areas in terms of the water availability. Furthermore, we also identify the influential source areas where land use change may considerably reduce a given target sink's water reception (from our example of the Ucayali River basin outlet, rainfall by 5-12 % and runoff by 19-50 % according to scenarios). Sensitive sinks and influential sources are therefore suggested as hotspots for achieving sustainable land-water management.

Geomorphic and biophysical factors affecting water tracks in northern Alaska

NASA Astrophysics Data System (ADS)

Trochim, E. D.; Jorgenson, M. T.; Prakash, A.; Kane, D. L.

2016-03-01

A better understanding of water movement on hillslopes in Arctic environments is necessary for evaluating the effects of climate variability. Drainage networks include a range of features that vary in transport capacity from rills to water tracks to rivers. This research focuses on describing and classifying water tracks, which are saturated linear-curvilinear stripes that act as first-order pathways for transporting water off of hillslopes into valley bottoms and streams. Multiple factor analysis was used to develop five water tracks classes based on their geomorphic, soil, and vegetation characteristics. The water track classes were then validated using conditional inference trees, to verify that the classes were repeatable. Analysis of the classes and their characteristics indicate that water tracks cover a broad spectrum of patterns and processes primarily driven by surficial geology. This research demonstrates an improved approach to quantifying water track characteristics for specific areas, which is a major step toward understanding hydrological processes and feedbacks within a region.

Characterization factors for water consumption and greenhouse gas emissions based on freshwater fish species extinction.

PubMed

Hanafiah, Marlia M; Xenopoulos, Marguerite A; Pfister, Stephan; Leuven, Rob S E W; Huijbregts, Mark A J

2011-06-15

Human-induced changes in water consumption and global warming are likely to reduce the species richness of freshwater ecosystems. So far, these impacts have not been addressed in the context of life cycle assessment (LCA). Here, we derived characterization factors for water consumption and global warming based on freshwater fish species loss. Calculation of characterization factors for potential freshwater fish losses from water consumption were estimated using a generic species-river discharge curve for 214 global river basins. We also derived characterization factors for potential freshwater fish species losses per unit of greenhouse gas emission. Based on five global climate scenarios, characterization factors for 63 greenhouse gas emissions were calculated. Depending on the river considered, characterization factors for water consumption can differ up to 3 orders of magnitude. Characterization factors for greenhouse gas emissions can vary up to 5 orders of magnitude, depending on the atmospheric residence time and radiative forcing efficiency of greenhouse gas emissions. An emission of 1 ton of CO₂ is expected to cause the same impact on potential fish species disappearance as the water consumption of 10-1000 m³, depending on the river basin considered. Our results make it possible to compare the impact of water consumption with greenhouse gas emissions.

Construction of estimated flow- and load-duration curves for Kentucky using the Water Availability Tool for Environmental Resources (WATER)

USGS Publications Warehouse

Unthank, Michael D.; Newson, Jeremy K.; Williamson, Tanja N.; Nelson, Hugh L.

2012-01-01

Flow- and load-duration curves were constructed from the model outputs of the U.S. Geological Survey's Water Availability Tool for Environmental Resources (WATER) application for streams in Kentucky. The WATER application was designed to access multiple geospatial datasets to generate more than 60 years of statistically based streamflow data for Kentucky. The WATER application enables a user to graphically select a site on a stream and generate an estimated hydrograph and flow-duration curve for the watershed upstream of that point. The flow-duration curves are constructed by calculating the exceedance probability of the modeled daily streamflows. User-defined water-quality criteria and (or) sampling results can be loaded into the WATER application to construct load-duration curves that are based on the modeled streamflow results. Estimates of flow and streamflow statistics were derived from TOPographically Based Hydrological MODEL (TOPMODEL) simulations in the WATER application. A modified TOPMODEL code, SDP-TOPMODEL (Sinkhole Drainage Process-TOPMODEL) was used to simulate daily mean discharges over the period of record for 5 karst and 5 non-karst watersheds in Kentucky in order to verify the calibrated model. A statistical evaluation of the model's verification simulations show that calibration criteria, established by previous WATER application reports, were met thus insuring the model's ability to provide acceptably accurate estimates of discharge at gaged and ungaged sites throughout Kentucky. Flow-duration curves are constructed in the WATER application by calculating the exceedence probability of the modeled daily flow values. The flow-duration intervals are expressed as a percentage, with zero corresponding to the highest stream discharge in the streamflow record. Load-duration curves are constructed by applying the loading equation (Load = Flow*Water-quality criterion) at each flow interval.

Future water availability in North African dams simulated by high-resolution regional climate models

NASA Astrophysics Data System (ADS)

Tramblay, Yves; Jarlan, Lionel; Hanich, Lahoucine; Somot, Samuel

2016-04-01

In North Africa, the countries of Morocco, Algeria and Tunisia are already experiencing water scarcity and a strong interannual variability of precipitation. To better manage their existing water resources, several dams and reservoirs have been built on most large river catchments. The objective of this study is to provide quantitative scenarios of future changes in water availability for the 47 major dams and reservoirs catchments located in North Africa. An ensemble of regional climate models (RCM) with a spatial resolution of 12km, driven by different general circulation models (GCM), from the EuroCORDEX experiment have been considered to analyze the projected changes on temperature, precipitation and potential evapotranspiration (PET) for two scenarios (RCP4.5 and RCP8.5) and two time horizons (2040-2065 and 2065-2090). PET is estimated from RCM outputs either with the FAO-Penman-Monteith (PM) equation, requiring air temperature, relative humidity, net radiation and wind, or with the Hargreave Samani (HS) equation, requiring only air temperature. The water balance is analyzed by comparing the climatic demand and supply of water, considering that for most of these catchments groundwater storage is negligible over long time periods. Results indicated a future temperature increase for all catchments between +1.8° and +4.2°, depending on the emission scenario and the time period considered. Precipitation is projected to decrease between -14% to -27%, mainly in winter and spring, with a strong East to West gradient. PET computed from PM or HS formulas provided very similar estimates and projections, ranging between +7% to +18%. Changes in PET are mostly driven by rising temperatures and are greatest during dry summer months than for the wet winter season. Therefore the increased PET has a lower impact than declining precipitation on future water availability, which is expected to decrease by -19% to -33% on average.

Availability, Sustainability, and Suitability of Ground Water, Rogers Mesa, Delta County, Colorado - Types of Analyses and Data for Use in Subdivision Water-Supply Reports

USGS Publications Warehouse

Watts, Kenneth R.

2008-01-01

The population of Delta County, Colorado, like that in much of the Western United States, is forecast to increase substantially in the next few decades. A substantial portion of the increased population likely will reside in rural subdivisions and use residential wells for domestic water supplies. In Colorado, a subdivision developer is required to submit a water-supply plan through the county for approval by the Colorado Division of Water Resources. If the water supply is to be provided by wells, the water-supply plan must include a water-supply report. The water-supply report demonstrates the availability, sustainability, and suitability of the water supply for the proposed subdivision. During 2006, the U.S. Geological Survey, in cooperation with Delta County, Colorado, began a study to develop criteria that the Delta County Land Use Department can use to evaluate water-supply reports for proposed subdivisions. A table was prepared that lists the types of analyses and data that may be needed in a water-supply report for a water-supply plan that proposes the use of ground water. A preliminary analysis of the availability, sustainability, and suitability of the ground-water resources of Rogers Mesa, Delta County, Colorado, was prepared for a hypothetical subdivision to demonstrate hydrologic analyses and data that may be needed for water-supply reports for proposed subdivisions. Rogers Mesa is a 12-square-mile upland mesa located along the north side of the North Fork Gunnison River about 15 miles east of Delta, Colorado. The principal land use on Rogers Mesa is irrigated agriculture, with about 5,651 acres of irrigated cropland, grass pasture, and orchards. The principal source of irrigation water is surface water diverted from the North Fork Gunnison River and Leroux Creek. The estimated area of platted subdivisions on or partially on Rogers Mesa in 2007 was about 4,792 acres of which about 2,756 acres was irrigated land in 2000. The principal aquifer on Rogers

A Framework Predicting Water Availability in a Rapidly Growing, Semi-Arid Region under Future Climate Change

NASA Astrophysics Data System (ADS)

Han, B.; Benner, S. G.; Glenn, N. F.; Lindquist, E.; Dahal, K. R.; Bolte, J.; Vache, K. B.; Flores, A. N.

2014-12-01

Climate change can lead to dramatic variations in hydrologic regime, affecting both surface water and groundwater supply. This effect is most significant in populated semi-arid regions where water availability are highly sensitive to climate-induced outcomes. However, predicting water availability at regional scales, while resolving some of the key internal variability and structure in semi-arid regions is difficult due to the highly non-linearity relationship between rainfall and runoff. In this study, we describe the development of a modeling framework to evaluate future water availability that captures elements of the coupled response of the biophysical system to climate change and human systems. The framework is built under the Envision multi-agent simulation tool, characterizing the spatial patterns of water demand in the semi-arid Treasure Valley area of Southwest Idaho - a rapidly developing socio-ecological system where urban growth is displacing agricultural production. The semi-conceptual HBV model, a population growth and allocation model (Target), a vegetation state and transition model (SSTM), and a statistically based fire disturbance model (SpatialAllocator) are integrated to simulate hydrology, population and land use. Six alternative scenarios are composed by combining two climate change scenarios (RCP4.5 and RCP8.5) with three population growth and allocation scenarios (Status Quo, Managed Growth, and Unconstrained Growth). Five-year calibration and validation performances are assessed with Nash-Sutcliffe efficiency. Irrigation activities are simulated using local water rights. Results show that in all scenarios, annual mean stream flow decreases as the projected rainfall increases because the projected warmer climate also enhances water losses to evapotranspiration. Seasonal maximum stream flow tends to occur earlier than in current conditions due to the earlier peak of snow melting. The aridity index and water deficit generally increase in the

FINANCING ASSISTANCE AVAILABLE FOR SMALL PUBLIC WATER SYSTEMS

EPA Science Inventory

Many small and very small drinking water systems require repair and upgrading if they are to comply with the Safe Drinking Water Act of 1974 and its amendments. Often, dispersed population makes infracstructure expensive on a per-capita basis. Funding shortages at the federal, ...

Contextual and sociopsychological factors in predicting habitual cleaning of water storage containers in rural Benin

NASA Astrophysics Data System (ADS)

Stocker, Andrea; Mosler, Hans-Joachim

2015-04-01

Recontamination of drinking water occurring between water collection at the source and the point of consumption is a current problem in developing countries. The household drinking water storage container is one source of contamination and should therefore be cleaned regularly. First, the present study investigated contextual factors that stimulate or inhibit the development of habitual cleaning of drinking water storage containers with soap and water. Second, based on the Risk, Attitudes, Norms, Abilities, and Self-regulation (RANAS) Model of behavior, the study aimed to determine which sociopsychological factors should be influenced by an intervention to promote habitual cleaning. In a cross-sectional study, 905 households in rural Benin were interviewed by structured face-to-face interviews. A forced-entry regression analysis was used to determine potential contextual factors related to habitual cleaning. Subsequently, a hierarchical regression was conducted with the only relevant contextual factor entered in the first step (R2 = 6.7%) and the sociopsychological factors added in the second step (R2 = 62.5%). Results showed that households using a clay container for drinking water storage had a significantly weaker habit of cleaning their water storage containers with soap and water than did households using other types of containers (β = -0.10). The most important sociopsychological predictors of habitual cleaning were commitment (β = 0.35), forgetting (β = -0.22), and self-efficacy (β = 0.14). The combined investigation of contextual and sociopsychological factors proved beneficial in terms of developing intervention strategies. Possible interventions based on these findings are recommended.

Water-quality assessment of the Potomac River Basin: analysis of available pesticide data, 1972-1990

USGS Publications Warehouse

Zappia, Humbert; Fisher, Gary T.

1997-01-01

A study of available data for the period from 1972 to 1990 was conducted to characterize the occurrence and distribution of pesticides in sur-face water, bottom material, ground water, and fish tissue in the Potomac River Basin. The study was conducted by the Potomac River study unit of the U.S. Geological Survey?s National Water-Quality Assessment (NAWQA) program. Exist-ing data coverage was evaluated to guide future data-collection activities. Data from computer data bases and from published and unpublished reports were obtained from local, State, and Fed-eral agencies in the four Potomac River Basin states and the District of Columbia. Data are available for all environmental media, but geo-graphic and temporal coverage are limited. Clusters of data occur in the north-central parts of the basin, with numerous samples at discrete loca-tions in the Shenandoah and Monocacy River Basins, along the mainstem Potomac River, in the Washington, D.C., area, and in streams along the Potomac Estuary. Much of the available surface-water and bottom-material data are from the ear-lier years of the period of interest, the ground-water data are from the middle years, and the fish-tissue data are distributed over much of the period. Overall, temporal coverage is not sufficient for analysis of trends. Comparisons between different sample media are possible in some areas of the Potomac River Basin, particularly in the northern end of the Great Valley. Residual concentrations of some pesticides have been found in surface water, bottom mate-rial, ground water, and fish tissue. Samples have been analyzed for a total of at least 69 pesticides and related compounds in surface water, bottom material, ground water, and fish tissue. Most con-centrations of the pesticides analyzed during the period from 1972 to 1990 were less than or equal to reporting limits. For surface-water samples, 13 out of 41 pes-ticides and related compounds analyzed had concentrations equal to or greater than the

Factors affecting the photoproduction of ammonia from dinitrogen and water by the cyanobacterium Anabaena sp. strain ATCC 33047.

PubMed

Ramos, J L; Guerrero, M G; Losada, M

1987-04-01

Synthesis of ammonia from dinitrogen and water by suspensions of Anabaena sp. Strain ATCC 33047 treated with the glutamine synthetase inhibitor L-methionine-D,L-sulfoximine is strictly dependent on light. Under otherwise optimal conditions, the yield of ammonia production is influenced by irradiance, as well as by the density, depth, and turbulence of the cell suspension. The interaction among these factors seems to determine the actual amount of light available to each single cell or filament in the suspension for the photoproduction process. Under convenient illumination, the limiting factor in the synthesis of ammonia seems to be the cellular nitrogenase activity level, but under limiting light conditions the limiting factor could, however, be the assimilatory power required for nitrogen fixation. Photosynthetic ammonia production from atmospheric nitrogen and water can operate with an efficiency of ca. 10% of its theoretical maximum, representing a remarkable process for the conversion of light energy into chemical energy.

User's Guide to the Water-Analysis Screening Tool (WAST): A Tool for Assessing Available Water Resources in Relation to Aquatic-Resource Uses

USGS Publications Warehouse

Stuckey, Marla H.; Kiesler, James L.

2008-01-01

A water-analysis screening tool (WAST) was developed by the U.S. Geological Survey, in partnership with the Pennsylvania Department of Environmental Protection, to provide an initial screening of areas in the state where potential problems may exist related to the availability of water resources to meet current and future water-use demands. The tool compares water-use information to an initial screening criteria of the 7-day, 10-year low-flow statistic (7Q10) resulting in a screening indicator for influences of net withdrawals (withdrawals minus discharges) on aquatic-resource uses. This report is intended to serve as a guide for using the screening tool. The WAST can display general basin characteristics, water-use information, and screening-indicator information for over 10,000 watersheds in the state. The tool includes 12 primary functions that allow the user to display watershed information, edit water-use and water-supply information, observe effects downstream from edited water-use information, reset edited values to baseline, load new water-use information, save and retrieve scenarios, and save output as a Microsoft Excel spreadsheet.

Assessment of global water security: moving beyond water scarcity assessment

NASA Astrophysics Data System (ADS)

Wada, Y.; Gain, A. K.; Giupponi, C.

2015-12-01

Water plays an important role in underpinning equitable, stable and productive societies, and the ecosystems on which we depend. Many international river basins are likely to experience 'low water security' over the coming decades. Hence, ensuring water security along with energy and food securities has been recognised as priority goals in Sustainable Development Goals (SDGs) by the United Nations. This water security is not rooted only in the limitation of physical resources, i.e. the shortage in the availability of freshwater relative to water demand, but also on social and economic factors (e.g. flawed water planning and management approaches, institutional incapability to provide water services, unsustainable economic policies). Until recently, advanced tools and methods are available for assessment of global water scarcity. However, integrating both physical and socio-economic indicators assessment of water security at global level is not available yet. In this study, we present the first global understanding of water security using a spatial multi-criteria analysis framework that goes beyond available water scarcity assessment. For assessing water security at global scale, the term 'security' is conceptualized as a function of 'availability', 'accessibility to services', 'safety and quality', and 'management'. The Water security index is calculated by aggregating the indicators using both simple additive weighting (SAW) and ordered weighted average (OWA).

Oil/water/rock wettability: Influencing factors and implications for low salinity water flooding in carbonate reservoirs

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

Chen, Yongqiang; Xie, Quan; Sari, Ahmad

Wettability of the oil/brine/rock system is an essential petro-physical parameter which governs subsurface multiphase flow behaviour and the distribution of fluids, thus directly affecting oil recovery. Recent studies [1–3] show that manipulation of injected brine composition can enhance oil recovery by shifting wettability from oil-wet to water-wet. However, what factor(s) control system wettability has not been completely elucidated due to incomplete understanding of the geochemical system. To isolate and identify the key factors at play we used in this paper SO 4 2—free solutions to examine the effect of salinity (formation brine/FB, 10 times diluted formation brine/10 dFB, and 100more » times diluted formation brine/100 dFB) on the contact angle of oil droplets at the surface of calcite. We then compared contact angle results with predictions of surface complexation by low salinity water using PHREEQC software. We demonstrate that the conventional dilution approach likely triggers an oil-wet system at low pH, which may explain why the low salinity water EOR-effect is not always observed by injecting low salinity water in carbonated reservoirs. pH plays a fundamental role in the surface chemistry of oil/brine interfaces, and wettability. Our contact angle results show that formation brine triggered a strong water-wet system (35°) at pH 2.55, yet 100 times diluted formation brine led to a strongly oil-wet system (contact angle = 175°) at pH 5.68. Surface complexation modelling correctly predicted the wettability trend with salinity; the bond product sum ([>CaOH 2 +][–COO -] + [>CO 3 -][–NH +] + [>CO 3 -][–COOCa +]) increased with decreasing salinity. Finally, at pH < 6 dilution likely makes the calcite surface oil-wet, particularly for crude oils with high base number. Yet, dilution probably causes water wetness at pH > 7 for crude oils with high acid number.« less

Oil/water/rock wettability: Influencing factors and implications for low salinity water flooding in carbonate reservoirs

DOE PAGES

Chen, Yongqiang; Xie, Quan; Sari, Ahmad; ...

2017-11-21

Wettability of the oil/brine/rock system is an essential petro-physical parameter which governs subsurface multiphase flow behaviour and the distribution of fluids, thus directly affecting oil recovery. Recent studies [1–3] show that manipulation of injected brine composition can enhance oil recovery by shifting wettability from oil-wet to water-wet. However, what factor(s) control system wettability has not been completely elucidated due to incomplete understanding of the geochemical system. To isolate and identify the key factors at play we used in this paper SO 4 2—free solutions to examine the effect of salinity (formation brine/FB, 10 times diluted formation brine/10 dFB, and 100more » times diluted formation brine/100 dFB) on the contact angle of oil droplets at the surface of calcite. We then compared contact angle results with predictions of surface complexation by low salinity water using PHREEQC software. We demonstrate that the conventional dilution approach likely triggers an oil-wet system at low pH, which may explain why the low salinity water EOR-effect is not always observed by injecting low salinity water in carbonated reservoirs. pH plays a fundamental role in the surface chemistry of oil/brine interfaces, and wettability. Our contact angle results show that formation brine triggered a strong water-wet system (35°) at pH 2.55, yet 100 times diluted formation brine led to a strongly oil-wet system (contact angle = 175°) at pH 5.68. Surface complexation modelling correctly predicted the wettability trend with salinity; the bond product sum ([>CaOH 2 +][–COO -] + [>CO 3 -][–NH +] + [>CO 3 -][–COOCa +]) increased with decreasing salinity. Finally, at pH < 6 dilution likely makes the calcite surface oil-wet, particularly for crude oils with high base number. Yet, dilution probably causes water wetness at pH > 7 for crude oils with high acid number.« less

Water rights in areas of ground-water mining

USGS Publications Warehouse

Thomas, Harold E.

1955-01-01

Ground-water mining, the progressive depletion of storage in a ground-water reservoir, has been going on for several years in some areas, chiefly in the Southwestern States. In some of these States a water right is based on ownership of land overlying the ground-water reservoir and does not depend upon putting the water to use; in some States a right is based upon priority of appropriation and use and may be forfeited if the water is allowed to go unused for a specified period, but ownership of land is not essential; and in several States both these doctrines or modifications thereof are accepted, and each applies to certain classes of water or to certain conditions of development.Experience to date indicates that a cure for ground-water mining does not necessarily depend upon the water-rights doctrine that is accepted in the area. Indeed, some recent court decisions have incorporated both the areal factor of the landownership doctrines and the time factor of the appropriation doctrine. Overdraft can be eliminated if water is available from another source to replace some of the water taken from the affected aquifer. In areas where no alternate source of supply is available at reasonable cost, public opinion so far appears to favor treating ground water as a nonrenewable resource comparable to petroleum and metals, and mining it until the supply is exhausted, rather than curbing the withdrawals at an earlier date.