WorldWideScience

Sample records for rangeland watershed water

  1. Simulating soil moisture change in a semiarid rangeland watershed with a process-based water-balance model

    Science.gov (United States)

    Howard Evan Canfield; Vicente L. Lopes

    2000-01-01

    A process-based, simulation model for evaporation, soil water and streamflow (BROOK903) was used to estimate soil moisture change on a semiarid rangeland watershed in southeastern Arizona. A sensitivity analysis was performed to select parameters affecting ET and soil moisture for calibration. Automatic parameter calibration was performed using a procedure based on a...

  2. The geomorphic legacy of water and erosion control structures in a semiarid rangeland watershed

    Science.gov (United States)

    Nichols, Mary H.; Magirl, Christopher S.; Sayre, N.F.; Shaw, Jeremy R.

    2017-01-01

    Control over water supply and distribution is critical for agriculture in drylands where manipulating surface runoff often serves the dual purpose of erosion control. However, little is known of the geomorphic impacts and legacy effects of rangeland water manipulation infrastructure, especially if not maintained. This study investigated the geomorphic impacts of structures such as earthen berms, water control gates, and stock tanks, in a semiarid rangeland in the southwestern USA that is responding to both regional channel incision that was initiated over a century ago, and a more recent land use change that involved cattle removal and abandonment of structures. The functional condition of remnant structures was inventoried, mapped, and assessed using aerial imagery and lidar data. Headcut initiation, scour, and channel incision associated with compromised lateral channel berms, concrete water control structures, floodplain water spreader berms, and stock tanks were identified as threats to floodplains and associated habitat. Almost half of 27 identified lateral channel berms (48%) have been breached and 15% have experienced lateral scour; 18% of 218 shorter water spreader berms have been breached and 17% have experienced lateral scour. A relatively small number of 117 stock tanks (6%) are identified as structurally compromised based on analysis of aerial imagery, although many currently do not provide consistent water supplies. In some cases, the onset of localized disturbance is recent enough that opportunities for mitigation can be identified to alter the potentially damaging erosion trajectories that are ultimately driven by regional geomorphic instability. Understanding the effects of prior land use and remnant structures on channel and floodplain morphologic condition is critical because both current land management and future land use options are constrained by inherited land use legacy effects.

  3. Sediment dynamics and sources in a grazed hardwood rangeland watershed

    Science.gov (United States)

    Melvin R. George; Neil K. McDougald; Kenneth W. Tate; Royce Larsen

    2002-01-01

    From 1994 to 1998 we documented sediment transport dynamics and sources in a 137 ha grazed hardwood rangeland watershed on granitic soils at the San Joaquin Experimental Range in Madera County. Sediment transport for this watershed was determined by measuring total suspended solids, bedload and flow at an H-flume installed in 1994. Sediment movement as bedload is the...

  4. Criterion I: Soil and water conservation on rangelands [Chapter 2

    Science.gov (United States)

    Michael G. (Sherm) Karl; Paul T. Tueller; Gerald E. Schuman; Mark R. Vinson; James L. Fogg; Ronald W. Shafer; David A. Pyke; D. Terrance Booth; Steven J. Borchard; William G. Ypsilantis; Richard H. Barrett

    2010-01-01

    The Sustainable Rangelands Roundtable (SRR) has explicitly included conservation and maintenance of soil and water resources as a criterion of rangeland sustainability. Within the soil/water criterion, 10 indicators ­ five soil-based and five water-based - were developed through the expert opinions of rangeland scientists, rangeland management agency personnel, non-...

  5. Assessment of rangeland ecosystem conditions, Salt Creek watershed and Dugout Ranch, southeastern Utah

    Science.gov (United States)

    Bowker, M.A.; Miller, M.E.; Belote, R.T.

    2012-01-01

    Increasingly, dry rangelands are being valued for multiple services beyond their traditional value as a forage production system. Additional ecosystem services include the potential to store carbon in the soil and plant biomass. In addition, dust emissions from rangelands might be considered an ecosystem detriment, the opposite of an ecosystem service. Dust emitted may have far-reaching impacts, for example, reduction of local air quality, as well as altering regional water supplies through effects on snowpack. Using an extensive rangeland monitoring dataset in the greater Canyonlands region (Utah, USA), we developed a method to estimate indices of the provisioning of three ecosystem services (forage production, dust retention, C storage) and one ecosystem property (nativeness), taking into account both ecosystem type and alternative states within that ecosystem type. We also integrated these four indices into a multifunctionality index. Comparing the currently ungrazed Canyonlands National Park watersheds to the adjacent Dugout Ranch pastures, we found clearly higher multifunctionality was attained in the Park, and that this was primarily driven by greater C-storage and better dust retention. It is unlikely to maximize all benefits and minimize all detriments at the same time. Some goods and services may have synergistic interactions; for example, managing for carbon storage will increase plant and biocrust cover likely lowering dust emission. Likewise, some may have antagonistic interactions. For instance, if carbon is consumed as biomass for livestock production, then carbon storage may be reduced. Ultimately our goal should be to quantify the monetary consequences of specific land use practices for multiple ecosystem services and determine the best land use and adaptive management practices for attaining multiple ecosystem services, minimizing economic detriments, and maximizing economic benefits from multi-commodity rangelands. Our technique is the first step

  6. A Hydrogeophysics Approach to Investigate Upland-Stream Connectivity on a Rangeland Hillslope in the Upper Crow Creek Watershed in Southeastern Wyoming

    Science.gov (United States)

    Carey, A. M.; Flinchum, B. A.; Paige, G. B.; Carr, B.; Miller, S. N.; Holbrook, W. S.

    2015-12-01

    Nearly all streamflow at one time passes through or over a hillslope prior to reaching the stream network. Knowledge of how this water is attenuated and delayed over a variety of hillslope conditions is critical for understanding the mechanisms controlling the spatial and temporal distribution of streamflow response. In semi-arid rangeland environments, these mechanisms remain unclear. Non- invasive geophysical methods coupled with traditional hydrological tools can provide the necessary insights into the dynamics of how upland hillslopes and streams are episodically connected. We collected approximately 1.4 km of ground penetrating radar (GPR) data to characterize the subsurface structure of a rangeland hillslope in the Upper Crow Creek Watershed and identify subsurface fractures. A field study integrating variable intensity rainfall simulation with time-lapse electrical resistivity tomography (ERT) was then conducted on four runoff plots positioned on the hillslope, to quantify the real-time partitioning of rainfall into surface and subsurface response. Runoff varied significantly across the plots due to spatial variability in vegetation cover, with a maximum and minimum peak runoff rate of 82 mm hr-1 and 7 mm hr-1 respectively. Time-lapse ERT data suggest the potential for infiltrated water to move preferentially through fractured regions in the subsurface identified by the GPR. Conductivity probes and pressure transducers positioned in the adjacent stream showed changes in electrical conductivity and depth following rainfall applications, suggesting hillslope connectivity with fairly rapid subsurface flow. Information obtained from this study will allow us to improve our understanding of the coupling of upland hillslopes and adjacent stream networks in complex rangeland environments.

  7. Telemetric system for hydrology and water quality monitoring in watersheds of northern New Mexico, USA.

    Science.gov (United States)

    Meyer, Michael L; Huey, Greg M

    2006-05-01

    This study utilized telemetric systems to sample microbes and pathogens in forest, burned forest, rangeland, and urban watersheds to assess surface water quality in northern New Mexico. Four sites included remote mountainous watersheds, prairie rangelands, and a small urban area. The telemetric system was linked to dataloggers with automated event monitoring equipment to monitor discharge, turbidity, electrical conductivity, water temperature, and rainfall during base flow and storm events. Site data stored in dataloggers was uploaded to one of three types of telemetry: 1) radio in rangeland and urban settings; 2) a conventional phone/modem system with a modem positioned at the urban/forest interface; and 3) a satellite system used in a remote mountainous burned forest watershed. The major variables affecting selection of each system were site access, distance, technology, and cost. The systems were compared based on operation and cost. Utilization of telecommunications systems in this varied geographic area facilitated the gathering of hydrologic and water quality data on a timely basis.

  8. Water and Poverty in Two Colombian Watersheds

    Directory of Open Access Journals (Sweden)

    Nancy Johnson

    2009-02-01

    Full Text Available Watersheds, especially in the developing world, are increasingly being managed for both environmental conservation and poverty alleviation. How complementary are these objectives? In the context of a watershed, the actual and potential linkages between land and water management and poverty are complex and likely to be very site specific and scale dependent. This study analyses the importance of watershed resources in the livelihoods of the poor in two watersheds in the Colombian Andes. Results of the participatory poverty assessment reveal significant decreases in poverty in both watersheds over the past 25 years, which was largely achieved by the diversification of livelihoods outside of agriculture. Water is an important resource for household welfare. However, opportunities for reducing poverty by increasing the quantity or quality of water available to the poor may be limited. While improved watershed management may have limited direct benefits in terms of poverty alleviation, there are important indirect linkages between watershed management and poverty, mainly through labour and service markets. The results suggest that at the level of the watershed the interests of the rich and the poor are not always in conflict over water. Sectoral as well as socio-economic differences define stakeholder groups in watershed management. The findings have implications for policymakers, planners and practitioners in various sectors involved in the implementation of integrated water resources management (IWRM.

  9. Effects of integrated watershed management on livestock water productivity in water scarce areas in Ethiopia

    Science.gov (United States)

    Descheemaeker, Katrien; Mapedza, Everisto; Amede, Tilahun; Ayalneh, Wagnew

    In the water scarce Lenche Dima watershed in the northern Ethiopian highlands community based integrated watershed management was implemented to fight land degradation, raise agricultural productivity and improve farmers’ livelihoods. The effects of two interventions, namely exclosures and water harvesting structures, were assessed based on data from farmers’ interviews, measurements of feed biomass production, and estimates of energy production and requirements. Water used for livestock feed production was obtained through simple soil water balance modelling. By protecting 40% of the rangelands, the water productivity of the feed increased by about 20%. This indicated that exclosure establishment could lead to similar improvements in livestock water productivity (LWP, defined as the ratio of livestock benefits over the water used in producing these). Water harvesting structures ensured year-round water availability in the homestead, which resulted in less energy used for walking to drinking points. A considerable amount of energy was thus saved, which could be used for livestock production and improved animal health without additional water use. Besides restoring regulating and supporting ecosystem services, both interventions led to a more efficient use of the scarce water resources for biomass and livestock production.

  10. Turbidity as an Indicator of Water Quality in Diverse Watersheds of the Upper Pecos River Basin

    Directory of Open Access Journals (Sweden)

    Gregory M. Huey

    2010-06-01

    Full Text Available Microbial concentrations, total suspended solids (TSS and turbidity vary with stream hydrology and land use. Turbidity, TSS, and microbial concentrations, loads and yields from four watersheds were assessed: an unburned montane forest, a catastrophically burned montane forest, urban land use and rangeland prairie. Concentrations and loads for most water quality variables were greatest during storm events. Turbidity was an effective indicator of TSS, E. coli and Enterococci spp. The greatest threat to public health from microbial contamination occurs during storm runoff events. Efforts to manage surface runoff and erosion would likely improve water quality of the upper Pecos River basin in New Mexico, USA.

  11. Application of high resolution images from unmanned aircraft systems for watershed and rangeland science

    Science.gov (United States)

    UAS provide a new way to acquire hyperspatial data with a resolution of 6 cm that has not been available in the past. This hyperspatial data can be used to obtain detailed 1-m DEMs, mosaics of entire watersheds, detailed vegetation classification of bare soils and vegetation type, and input to mode...

  12. Restoring Degraded Rangelands in Jordan: Optimizing Mechanized Micro-Water Harvesting Technique Using Rangeland Hydrology and Erosion Model (RHEM)

    Science.gov (United States)

    Continuous population growth, recent refugee movement and migration as well as boundary restrictions and their implications on the nomadic lifestyle are additive pressure on rangelands throughout the Middle East. In particular, overgrazing through increased livestock herds threatens the Jordanian ra...

  13. Water use efficiency of six rangeland grasses under varied soil ...

    African Journals Online (AJOL)

    The changes in soil moisture content were measured by Gypsum Block which aided in determining the irrigation schedules. The grasses demonstrated varied levels of WUE which was evaluated by amount of biomass productivity in relation to evapotranspired water during the growing period. The three soil moisture content ...

  14. Evaluation of Surface Water Harvesting Potential in Aq Emam Watershed System in the Golestan Province

    Directory of Open Access Journals (Sweden)

    s. nazaryan

    2016-02-01

    of runoff production potential indicated that May and June accounted for the highest runoff and it can be inferred from these results that both of these months are characterized with storms which was confirmed by interviewing local residents and as range-land covers the largest land use in the basin as well as low vegetation density in the spring and summer due to overgrazing, much more runoff has been produced which is in line with the studies conducted by the Department of Natural Resources of the Golestan province in Aq Emam watershed (2003 as well as findings of Eftekhari et al. The results showed that the highest areas of the sub watershed 8, and 3 were suitable for rain water harvesting. Thus, the appropriate areas for rain water harvesting in the sub watersheds do not have a uniform spatial distribution according to the results. It can be argued that these sub basins are characterized by 4 criteria to be appropriate for rain water harvesting, which is in confirmation with Miliniai et al. Also according to the results, the areas suitable for rainwater harvesting in each sub-basin have heterogeneous spatial distribution as confirmed by the results of Eftekhari and Jin et al. Given the final map from integrating data layers, it was found that the central part of the study area has a good potential for rainwater harvesting and as results show, suitable area for water harvesting in the watershed coincides with range-lands that have a moderate crown cover as confirmed by the results reported by Tabatabaii et al. Conclusion: Finally it can be said that spatial evaluation and identification of proper areas for rain water harvesting is an important and necessary step in the application of rain water harvesting systems. Keywords: Surface water harvesting, Spatial evaluation, Sub watersheds priority, GIS, SCS

  15. An environmental assessment of United States drinking water watersheds

    Science.gov (United States)

    James Wickham; Timothy Wade; Kurt Riitters

    2011-01-01

    Abstract There is an emerging recognition that natural lands and their conservation are important elements of a sustainable drinking water infrastructure. We conducted a national, watershed-level environmental assessment of 5,265 drinking water watersheds using data on land cover, hydrography and conservation status. Approximately 78% of the conterminous United States...

  16. [Watershed water environment pollution models and their applications: a review].

    Science.gov (United States)

    Zhu, Yao; Liang, Zhi-Wei; Li, Wei; Yang, Yi; Yang, Mu-Yi; Mao, Wei; Xu, Han-Li; Wu, Wei-Xiang

    2013-10-01

    Watershed water environment pollution model is the important tool for studying watershed environmental problems. Through the quantitative description of the complicated pollution processes of whole watershed system and its parts, the model can identify the main sources and migration pathways of pollutants, estimate the pollutant loadings, and evaluate their impacts on water environment, providing a basis for watershed planning and management. This paper reviewed the watershed water environment models widely applied at home and abroad, with the focuses on the models of pollutants loading (GWLF and PLOAD), water quality of received water bodies (QUAL2E and WASP), and the watershed models integrated pollutant loadings and water quality (HSPF, SWAT, AGNPS, AnnAGNPS, and SWMM), and introduced the structures, principles, and main characteristics as well as the limitations in practical applications of these models. The other models of water quality (CE-QUAL-W2, EFDC, and AQUATOX) and watershed models (GLEAMS and MIKE SHE) were also briefly introduced. Through the case analysis on the applications of single model and integrated models, the development trend and application prospect of the watershed water environment pollution models were discussed.

  17. Indicators of rangeland health and functionality in the Intermountain West

    Science.gov (United States)

    Renee A. O' Brien; Curtis M. Johnson; Andrea M. Wilson; Van C. Elsbernd

    2003-01-01

    Rangelands comprise about 42 percent of the land area of the United States and provide vital land functions such as watershed, multiple-use, recreation, and other amenities. Currently, we do not know the status and trends of many of our nation's rangelands, and consistent protocols for describing rangeland system dynamics across land management agencies are...

  18. Monitoring African savanna water use and water stress from local to regional scale: supporting rangeland management (pilot experience in Kruger National Park, South Africa).

    Science.gov (United States)

    Andreu, Ana; Dube, Timothy; Nieto, Hector; González-Dugo, Maria P.; Hülsmann, Stephan

    2017-04-01

    Drought periods and erratic rainfall patterns across large parts of Africa result in water-limited environments like savannas, highly sensitive to land management practices and changes in climate. Over the Southern part of the continent, savannas are key productive landscapes supporting livestock, crops and rural livelihoods. Monitoring water use and the natural vegetation stress over these semi-arid complex ecosystems can support rangeland management, to maintain long-term productivity. However, the precision/resolution/accuracy of the information required for management will differ at each scale: farm-local (e.g. evaluating the effect of management practices, livestock densities, crop production and grazing), to watershed (e.g. evaluating the effect of fire, detection of vulnerable areas) and regional (e.g. early prediction of drought). To overcome these constrains, TIGER project 401 combines two approaches that take advantage of different conceptual and operational capabilities of Earth Observation data sources. Sentinel 2 high spatial (10 m) and temporal ( 5 days) resolution VIS/NIR images are used for a continuous monitoring of vegetation cover and unstressed evapotranspiration (ET - using Kc-FAO56 method). This methodology will provide the required resolution for farm-local scales, tracking separately the seasonal variations of each canopy layer growth (grass and trees). Meanwhile, lower spatial resolution (1 km) MODIS thermal data allow to determine a regional water stress index (ratio between actual ET, estimated using Two Source Energy Balance-TSEB, and potential ET), supporting the detection of vulnerable areas. The model framework was tested and validated over savanna-type experimental areas (Skukuza & Malopeni), and later applied over the whole Kruger National Park during 2015-2016.

  19. Watershed characteristics and water-quality trends and loads in 12 watersheds in Gwinnett County, Georgia

    Science.gov (United States)

    Joiner, John K.; Aulenbach, Brent T.; Landers, Mark N.

    2014-01-01

    The U.S. Geological Survey, in cooperation with Gwinnett County Department of Water Resources, established a Long-Term Trend Monitoring (LTTM) program in 1996. The LTTM program is a comprehensive, long-term, water-quantity and water-quality monitoring program designed to document and analyze the hydrologic and water-quality conditions of selected watersheds of Gwinnett County, Georgia. Water-quality monitoring initially began in six watersheds and was expanded to another six watersheds in 2001. As part of the LTTM program, streamflow, precipitation, water temperature, specific conductance, and turbidity were measured continuously at the 12 watershed monitoring stations for water years 2004–09. In addition, discrete water-quality samples were collected seasonally from May through October (summer) and November through April (winter), including one base-flow and three stormflow event composite samples, during the study period. Samples were analyzed for nutrients (nitrogen and phosphorus), total organic carbon, trace elements (total lead and total zinc), total dissolved solids, and total suspended sediment (total suspended solids and suspended-sediment concentrations). The sampling scheme was designed to identify variations in water quality both hydrologically and seasonally. The 12 watersheds were characterized for basin slope, population density, land use for 2009, and the percentage of impervious area from 2000 to 2009. Precipitation in water years 2004–09 was about 18 percent below average, and the county experienced exceptional drought conditions and below average runoff in water years 2007 and 2008. Watershed water yields, the percentage of precipitation that results in runoff, typically are lower in low precipitation years and are higher for watersheds with the highest percentages of impervious areas. A comparison of base-flow and stormflow water-quality samples indicates that turbidity and concentrations of total ammonia plus organic nitrogen, total

  20. A Stochastic Water Balance Framework for Lowland Watersheds

    Science.gov (United States)

    Thompson, Sally; MacVean, Lissa; Sivapalan, Murugesu

    2017-11-01

    The water balance dynamics in lowland watersheds are influenced not only by local hydroclimatic controls on energy and water availability, but also by imports of water from the upstream watershed. These imports result in a stochastic extent of inundation in lowland watersheds that is determined by the local flood regime, watershed topography, and the rate of loss processes such as drainage and evaporation. Thus, lowland watershed water balances depend on two stochastic processes—rainfall and local inundation dynamics. Lowlands are high productivity environments that are disproportionately associated with urbanization, high productivity agriculture, biodiversity, and flood risk. Consequently, they are being rapidly altered by human development—generally with clear economic and social motivation—but also with significant trade-offs in ecosystem services provision, directly related to changes in the components and variability of the lowland water balance. We present a stochastic framework to assess the lowland water balance and its sensitivity to two common human interventions—replacement of native vegetation with alternative land uses, and construction of local flood protection levees. By providing analytical solutions for the mean and PDF of the water balance components, the proposed framework provides a mechanism to connect human interventions to hydrologic outcomes, and, in conjunction with ecosystem service production estimates, to evaluate trade-offs associated with lowland watershed development.

  1. Design of Water Discharge of Medewi Watershed Using Avswat Model

    Science.gov (United States)

    Pramana, Y. H.; Purwanto, B. P.

    2013-12-01

    Medewi watersheds is located in the southern of Bali Island and its estuary is located in Medewi Beach at Kabupaten Jembrana. The exact location of Medewi watersheds is between Desa Medewi and Desa Pulukan, Kecamatan Pekutatan, Kabupaten Jembrana. The watersheds itself, due to its strategic location is used as a territorial border between the two villages. Geographically, Medewi watersheds is between 114o48'00' - 114o50'00' east longitude and 08o20'00' - 08o26,5'00' south latitude. The main river of Medewi Watersheds is 25,64 km long and is classified as a continuous river, the width of the watersheds itself is measured 128,2 km2. Medewi watersheds have two tributaries which is Medaan watersheds and Pangliman watersheds, both watersheds' heads are located in Medewi Beach. Medewi watersheds is often flooded and brings heavy toll to its surrounding areas and citizen. Therefore, there is an urgent need to perform engineering techniques to overcome the aforementioned problem. However, there is a slight issue in the definition of water discharge plan in the location. The water discharge plan, which is used as a basis to prevent flooding, is often inaccurate. That is the reason why it is needed to build a model in order to accurately find out the amount of water discharge in the study location. Medewi watersheds' area usage is as follow: bushes (9,44%), forestation (77,10%), farm (7,76%), settlement (2,15%), irrigation field (1,64%), rainfed field (1,88%) and crops field (0,48%). The result of our modeling using ASVAT shows that the maximum water discharge is 149,9 m3/sec. The discharge is calibrated with the available water discharge data log. According to AWLR data, it is known that the largest discharge occurred on June 2nd, 2009 and measured at 147,9 m3/sec. Our conclusion is that the model used in this study managed to approach the field result with minimum error.

  2. Using a dynamic model to assess trends in land degradation by water erosion in Spanish Rangelands

    Science.gov (United States)

    Ibáñez, Javier; Francisco Lavado-Contador, Joaquín; Schnabel, Susanne; Pulido-Fernández, Manuel; Martínez Valderrama, Jaime

    2014-05-01

    This work presents a model aimed at evaluating land degradation by water erosion in dehesas and montados of the Iberian Peninsula, that constitute valuable rangelands in the area. A multidisciplinary dynamic model was built including weather, biophysical and economic variables that reflect the main causes and processes affecting sheet erosion on hillsides of the study areas. The model has two main and two derived purposes: Purpose 1: Assessing the risk of degradation that a land-use system is running. Derived purpose 1: Early warning about land-use systems that are particularly threatened by degradation. Purpose 2: Assessing the degree to which different factors would hasten degradation if they changed from the typical values they show at present. Derived purpose 2: Evaluating the role of human activities on degradation. Model variables and parameters have been calibrated for a typical open woodland rangeland (dehesa or montado) defined along 22 working units selected from 10 representative farms and distributed throughout the Spanish region of Extremadura. The model is the basis for a straightforward assessment methodology which is summarized by the three following points: i) The risk of losing a given amount of soil before a given number of years was specifically estimated as the percentage of 1000 simulations where such a loss occurs, being the simulations run under randomly-generated scenarios of rainfall amount and intensity and meat and supplemental feed market prices; ii) Statistics about the length of time that a given amount of soil takes to be lost were calculated over 1000 stochastic simulations run until year 1000, thereby ensuring that such amount of soil has been lost in all of the simulations, i.e. the total risk is 100%; iii) Exogenous factors potentially affecting degradation, mainly climatic and economic, were ranked in order of importance by means of a sensitivity analysis. Particularly remarkable in terms of model performance is the major role

  3. Lawrence Livermore National Laboratory Surface Water Protection: A Watershed Approach

    Energy Technology Data Exchange (ETDEWEB)

    Coty, J

    2009-03-16

    This surface water protection plan (plan) provides an overview of the management efforts implemented at Lawrence Livermore National Laboratory (LLNL) that support a watershed approach to protect surface water. This plan fulfills a requirement in the Department of Energy (DOE) Order 450.1A to demonstrate a watershed approach for surface water protection that protects the environment and public health. This plan describes the use of a watershed approach within which the Laboratory's current surface water management and protections efforts have been structured and coordinated. With more than 800 million acres of land in the U.S. under federal management and stewardship, a unified approach across agencies provides enhanced resource protection and cost-effectiveness. The DOE adopted, along with other federal agencies, the Unified Federal Policy for a Watershed Approach to Federal Land and Resource Management (UFP) with a goal to protect water quality and aquatic ecosystems on federal lands. This policy intends to prevent and/or reduce water pollution from federal activities while fostering a cost-effective watershed approach to federal land and resource management. The UFP also intends to enhance the implementation of existing laws (e.g., the Clean Water Act [CWA] and National Environmental Policy Act [NEPA]) and regulations. In addition, this provides an opportunity for the federal government to serve as a model for water quality stewardship using a watershed approach for federal land and resource activities that potentially impact surface water and its uses. As a federal land manager, the Laboratory is responsible for a small but important part of those 800 million acres of land. Diverse land uses are required to support the Laboratory's mission and provide an appropriate work environment for its staff. The Laboratory comprises two sites: its main site in Livermore, California, and the Experimental Test Site (Site 300), near Tracy, California. The main site

  4. Water quality, sources of nitrate, and chemical loadings in the Geronimo Creek and Plum Creek watersheds, south-central Texas, April 2015–March 2016

    Science.gov (United States)

    Lambert, Rebecca B.; Opsahl, Stephen P.; Musgrove, MaryLynn

    2017-12-22

    Located in south-central Texas, the Geronimo Creek and Plum Creek watersheds have long been characterized by elevated nitrate concentrations. From April 2015 through March 2016, an assessment was done by the U.S. Geological Survey, in cooperation with the Guadalupe-Blanco River Authority and the Texas State Soil and Water Conservation Board, to characterize nitrate concentrations and to document possible sources of elevated nitrate in these two watersheds. Water-quality samples were collected from stream, spring, and groundwater sites distributed across the two watersheds, along with precipitation samples and wastewater treatment plant (WWTP) effluent samples from the Plum Creek watershed, to characterize endmember concentrations and isotopic compositions from April 2015 through March 2016. Stream, spring, and groundwater samples from both watersheds were collected during four synoptic sampling events to characterize spatial and temporal variations in water quality and chemical loadings. Water-quality and -quantity data from the WWTPs and stream discharge data also were considered. Samples were analyzed for major ions, selected trace elements, nutrients, and stable isotopes of water and nitrate.The dominant land use in both watersheds is agriculture (cultivated crops, rangeland, and grassland and pasture). The upper part of the Plum Creek watershed is more highly urbanized and has five major WWTPs; numerous smaller permitted wastewater outfalls are concentrated in the upper and central parts of the Plum Creek watershed. The Geronimo Creek watershed, in contrast, has no WWTPs upstream from or near the sampling sites.Results indicate that water quality in the Geronimo Creek watershed, which was evaluated only during base-flow conditions, is dominated by groundwater, which discharges to the stream by numerous springs at various locations. Nitrate isotope values for most Geronimo Creek samples were similar, which indicates that they likely have a common source (or

  5. Water quality trading opportunities in two sub-watersheds in the northern Lake Okeechobee watershed.

    Science.gov (United States)

    Corrales, Juliana; Naja, G Melodie; Bhat, Mahadev G; Miralles-Wilhelm, Fernando

    2017-07-01

    For decades, the increase of nutrient enrichment has threatened the ecological integrity and economic sustainability of many rivers, lakes, and coastal waters, including Lake Okeechobee, the second largest freshwater lake in the contiguous United States. Water quality trading programs have been an area of active development to both, reduce nutrient pollution and minimize abatement costs. The objective of this study was to apply a comprehensive modeling framework, integrating a hydrologic-water quality model with an economic model, to assess and compare the cost-effectiveness of a water quality trading program over a command-and-control approach in order to reduce phosphorus loadings to Lake Okeechobee. The Upper Kissimmee (UK) and Taylor Creek/Nubbin Slough (TCNS) sub-watersheds, identified as major sources of total phosphorus (TP) loadings to the lake, were selected for this analysis. The effect of different caps on the market potential was assessed while considering four factors: the least-cost abatement solutions, credit prices, potential cost savings, and credit supply and demand. Hypothetical trading scenarios were also developed, using the optimal caps selected for the two sub-watersheds. In both sub-watersheds, a phosphorus credit trading program was less expensive than the conventional command-and-control approach. While attaining cost-effectiveness, keeping optimal credit prices, and fostering market competition, phosphorus reduction targets of 46% and 32% were selected as the most appropriate caps in the UK and TCNS sub-watersheds, respectively. Wastewater treatment facilities and urban areas in the UK, and concentrated animal feeding operations in the TCNS sub-watershed were identified as potential credit buyers, whereas improved pastures were identified as the major credit sellers in both sub-watersheds. The estimated net cost savings resulting from implementing a phosphorus trading program in the UK and TCNS sub-watersheds were 76% ($ 34.9 million per

  6. Veterinary pharmaceutical contamination in mixed land use watersheds: from agricultural headwater to water monitoring watershed.

    Science.gov (United States)

    Jaffrézic, A; Jardé, E; Soulier, A; Carrera, L; Marengue, E; Cailleau, A; Le Bot, B

    2017-12-31

    Veterinary pharmaceuticals, widely used in intensive livestock production, may contaminate surface waters. Identifying their sources and pathways in watersheds is difficult because i) most veterinary pharmaceuticals are used in human medicine as well and ii) septic or sewer wastewater treatment plants (WWTP) can release pharmaceuticals into surface water, even in agricultural headwater watersheds. This study aimed to analyze the spatiotemporal variability of animal-specific, mixed-use, and human-specific pharmaceuticals, from agricultural headwaters with intensive livestock production and a WWTP to a watershed used for Water Framework Directive monitoring. Grab sampling was performed during one hydrological year upstream and downstream from a WWTP and at three dates in seven nested watersheds with areas of 1.9-84.1km 2 . Twenty pharmaceuticals were analyzed. Animal-specific pharmaceuticals were detected at all sampling dates upstream and downstream from the WWTP and at concentrations higher than those of human-specific pharmaceuticals. The predominance of animal-specific and mixed-use pharmaceuticals vs. human-specific pharmaceuticals observed at these sampling points was confirmed at the other sampling points. Animal-specific pharmaceuticals were detected mainly during runoff events and periods of manure spreading. A large percentage of mixed-use pharmaceuticals could come from animal sources, but it was difficult to determine. Mixed-use and human-specific pharmaceuticals predominated in the largest watersheds when runoff decreased. In areas of intensive livestock production, mitigation actions should focus on agricultural headwater watersheds to decrease the number of pathways and the transfer volume of veterinary pharmaceuticals, which can be the main contaminants. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Monitoring water quality and quantity of national watersheds in Turkey.

    Science.gov (United States)

    Odemis, Berkant; Evrendilek, Fatih

    2007-10-01

    National data from the hydrological network for 38 rivers out of 25 watersheds were used to detect spatial and temporal trends in water quality and quantity characteristics between 1995 and 2002. Assessment of water quality and quantity included flow rate, water temperature, pH, electrical conductivity, sodium adsorption rate, Na, K, Ca+Mg, CO(3), HCO(3), Cl, SO(4), and boron. Among the major ions assessed on a watershed basis, Turkish river waters are relatively high in Ca+Mg, Na and HCO(3), and low in K and CO(3). The watersheds in Turkey experienced a general trend of 16% decrease in flow rates between 1995 and 2002 at a mean annual rate of about 4 m(3) s(-1), with a considerable spatial variation. Similarly, there appeared to be an increasing trend in river water temperature, at a mean annual rate of about 0.2 degrees C. A substantial proportion of watersheds experienced an increase in pH, in particular, after 1997, with a maximum increase from 8.1 to 8.4 observed in Euphrates (P Big Menderes watersheds where intensive agricultural activities take place. Such continued levels may threaten biotic integrity and both drinking and irrigation water quality of rivers. Best multiple linear regression (MLR) models constructed both annually and monthly differed in R (2) values in accounting for variations of pH and water temperature only. The findings of the study can provide a useful assessment of controls over water quality and quantity and assist in devising integrated and sustainable management practices for watersheds at the regional scale in Turkey.

  8. Water-quality data analysis of the upper Gunnison River watershed, Colorado, 1989-99

    Science.gov (United States)

    Gurdak, Jason J.; Greve, Adrienne I.; Spahr, Norman E.

    2002-01-01

    different between agriculture and forest sites and between agriculture and urban land-use classified sites, median concentrations were low among all land-use settings. Median concentrations of total phosphorus were greatest in rangeland areas and least in urban areas. No significant differences were identified for median concentrations of total phosphorus in agriculture and forest land-use areas. Median concentrations of arsenic, lead, mercury, selenium, and silver were low or below reporting levels throughout the watershed. Aluminum, cadmium, copper, lead, manganese, and zinc concentrations were elevated near the town of Crested Butte and on Henson Creek upstream from Lake City, which may be explained by upstream areas of historical mining. Samples for six trace elements exceeded standards: cadmium, copper, lead, manganese, silver, and zinc. A downward trend (3 micrograms per liter per year) was identified for the dissolved iron concentration at a site on the Gunnison River at County Road 32 downstream from the city of Gunnison. Streambed-sediment samples from areas affected by historical mining also had elevated concentrations of some trace elements. Chlorophyll-a concentrations in samples from Blue Mesa Reservoir and streams in the Crested Butte and Gunnison areas were typical of unenriched to moderately enriched conditions. Median concentrations of 5-day biochemical oxygen demand concentrations for sites between Crested Butte and Blue Mesa Reservoir were less than 2 milligrams per liter. Occasional high (greater than 200 counts per 100 milliliters) concentrations for fecal coliform were determined at selected sites within the study area. However, median concentrations were less than 100 counts per 100 milliliters except for the Squaw Creek and Cimarron River areas in the western part of the watershed. Ground-water-quality data have been collected by the U.S. Geological Survey from 99 wells. Many wells were completed in aquifers composed of H

  9. Annual Report Card Shows Water Quality Improvements in Parts of the Mystic River Watershed

    Science.gov (United States)

    Each year, the US Environmental Protection Agency (EPA), in collaboration with the Mystic River Watershed Association (MyRWA), issues a Water Quality Report Card on water quality in the Mystic River watershed.

  10. RANGELAND DEGRADATION: EXTENT, IMPACTS, AND ALTERNATIVE RESTORATION TECHNIQUES IN THE RANGELANDS OF ETHIOPIA

    Directory of Open Access Journals (Sweden)

    Mohammed Mussa Abdulahi

    2016-12-01

    Full Text Available Rangeland degradation remains a serious impediment to improve pastoral livelihoods in the lowlands of Ethiopia. This review paper presents an overview of the extent of rangeland degradation, explores its drivers, discusses the potential impacts of rangeland degradation and also suggests alternative rangeland restoration techniques. It is intended to serve as an exploratory tool for ensuing more detailed quantitative analyses to support policy and investment programs to address rangeland degradation in Ethiopia. The extent of rangeland degradation increases with time, and the productivity of rangelands are losing if not given due attention. The major drivers leading to rangeland degradation includes climate change, overgrazing, bush encroachment, population pressure, drought, and government policy, encroachment of rain fed agriculture and decline of traditional resource management institution. Degradation of rangeland has resulted in substantial declines in rangeland condition, water potential, soil status, and animal performance, livestock holding at the household level and community become destitute. Another consequence of rangeland degradation is linked to food insecurity, poverty to the extent of food aid, expansion of aridity and the need for alternative livelihood and income diversification. Moreover, it has increasingly become a threat to the pastoral production systems, and has contributed towards increases in poverty and tribal conflicts over grazing land and water resources. In spite of these impacts, the adoption of alternative restoration techniques in the country is highly insufficient. To address rangeland degradation problems, there is a strong need to substantially increase the investments and strengthen the policy support for sustainable land management.

  11. Incorporating grazing into an eco-hydrologic model: Simulating coupled human and natural systems in rangelands

    Science.gov (United States)

    Reyes, J. J.; Liu, M.; Tague, C.; Choate, J. S.; Evans, R. D.; Johnson, K. A.; Adam, J. C.

    2013-12-01

    Rangelands provide an opportunity to investigate the coupled feedbacks between human activities and natural ecosystems. These areas comprise at least one-third of the Earth's surface and provide ecological support for birds, insects, wildlife and agricultural animals including grazing lands for livestock. Capturing the interactions among water, carbon, and nitrogen cycles within the context of regional scale patterns of climate and management is important to understand interactions, responses, and feedbacks between rangeland systems and humans, as well as provide relevant information to stakeholders and policymakers. The overarching objective of this research is to understand the full consequences, intended and unintended, of human activities and climate over time in rangelands by incorporating dynamics related to rangeland management into an eco-hydrologic model that also incorporates biogeochemical and soil processes. Here we evaluate our model over ungrazed and grazed sites for different rangeland ecosystems. The Regional Hydro-ecologic Simulation System (RHESSys) is a process-based, watershed-scale model that couples water with carbon and nitrogen cycles. Climate, soil, vegetation, and management effects within the watershed are represented in a nested landscape hierarchy to account for heterogeneity and the lateral movement of water and nutrients. We incorporated a daily time-series of plant biomass loss from rangeland to represent grazing. The TRY Plant Trait Database was used to parameterize genera of shrubs and grasses in different rangeland types, such as tallgrass prairie, Intermountain West cold desert, and shortgrass steppe. In addition, other model parameters captured the reallocation of carbon and nutrients after grass defoliation. Initial simulations were conducted at the Curlew Valley site in northern Utah, a former International Geosphere-Biosphere Programme Desert Biome site. We found that grasses were most sensitive to model parameters affecting

  12. Water development strategy as a driving force for sustained rangeland management by local communities in sub-Saharan Africa.

    Science.gov (United States)

    Pamo, Etienne Tedonkeng

    2004-12-01

    Water is the major food component for the maintenance of animals. Although Africa is endowed with diverse agricultural environments, the survival of animals in Sahelian and sub-Sahelian Africa is threatened by the lack of water. Animals need water as an essential nutrient, a component of the body, and for conductive or evaporative cooling. Water needs are met mainly through drinking free water and to a lesser extent by utilising water that forms part of the feed. However during the long dry season, surface water resources dwindle and the water content of available forage decreases, thereby increasing the animals' demand for water. Consequently animals have to walk for long distances to obtain adequate forage and water, which in turn raises the demand for these resources. Water can be used to direct and regulate rangeland management in this open access environment, to maintain range resources and to improve their quality. Water development, which takes into consideration usable forage, despite some intra- or inter-annual variability, plays an important role and its spatial distribution will affect the grazing intensity of forage resources. Sound water development and management strategies integrating local communities in the decision-making will set up a firm basis for sustained range management in the free and open access environment of sub-Saharan Africa where lack of financial input, social and cultural habits and above all the environmental condition do not permit large scale fencing as in other parts of the world.

  13. Water cycle observations in forest watersheds of Cambodia

    Science.gov (United States)

    Shimizu, A.; Tamai, K.; Kabeya, N.; Shimizu, T.; Iida, S. I.

    2015-12-01

    The Lower Mekong River flows through Cambodia, where forests cover ~60% of the country and are believed to have a marked effect on the water cycle. These tropical seasonal forests in the Cambodian flat lands are very precious in the Indochinese Peninsula as few forests of this type remain. However, few hydrological observations have been conducted in these areas. In Cambodia, deciduous and evergreen forests make up 42% and 33% of the total forest area, respectively. We established experimental watersheds both in deciduous and evergreen forests containing meteorological observation towers in Cambodia and collected various observational data since 2003 (O'Krieng, deciduous forest watershed including a 30-m-high observation tower, 2,245 km2; Stung Chinit, evergreen forest watershed including a 60-m-high observation tower, 3,700 km2 including three small watersheds). The basic data from these sites included various kinds of information related to the composition of vegetation, soil characteristics, etc. Hydrologic data was collected and linked to the above data; the main hydrologic research results follow. The water budget for each watershed was determined using an observational rainfall and runoff dataset. The evapotranspiration rate in an evergreen forest was obtained using various observational methods including the Bowen energy-balance ratio and the bandpass eddy covariance method. The annual evapotranspiration of evergreen forests, estimated using the Bowen energy-balance ratio method and water balance, was about 1100-1200 mm, corresponding to 70-80% of annual rainfall. While considering the importance of the presence of evergreen forest, we conducted sap flow measurements to analyze the transpiration process that maintains water uptake through root systems that reach to depths exceeding 8 m. Characteristics of the evaporation from the forest floor that form an important element of the evaporation system were estimated in both evergreen and deciduous forests.

  14. Estimating water user demand for certification of forest watershed services.

    Science.gov (United States)

    Jaung, Wanggi; Bull, Gary Q; Sumaila, Ussif Rashid; Markum; Putzel, Louis

    2018-02-16

    Eco-certification is one solution to the common problem of verification of delivery of services in payment for ecosystem services (PES) schemes. Certification incurs costs, which may limit uptake, so it should be able to benefit users of certified services for it succeeds. In part to inform a project targeting expansion of the Forest Stewardship Council's forest management certification to include ecosystem services, we tested market demand for a potential certification scheme for watershed services. Using choice experiments among end-users of water subject to an existing PES scheme in Lombok, Indonesia, we assessed potential business values of certification. Our results suggested that preferred business values included credible information disclosure on improved water quality, reduced flood risk, environmental safeguards, and/or social safeguards of the upstream forests. These preferences indicate potential demand for a certification of forest watershed services designed to provide such information to end users. Copyright © 2018 Elsevier Ltd. All rights reserved.

  15. Assessment of climate change impacts on water balance components of Heeia watershed in Hawaii

    OpenAIRE

    Leta, Olkeba Tolessa; El-Kadi, Aly I.; Dulai, Henrietta; Ghazal, Kariem A.

    2016-01-01

    Study region: Heeia watershed, Oahu, Hawaii, USA. Study focus: Hydrological models are useful tools for assessing the impact of climate change in watersheds. We evaluated the applicability of the Soil and Water Assessment Tool (SWAT) model in a case study of Heeia, Pacific-island watershed that has highly permeable volcanic soils and suffers from hydrological data scarcity. Applicability of the model was enhanced with several modifications to reflect unique watershed characteristics. The c...

  16. Community participation and implementation of water management instruments in watersheds

    Directory of Open Access Journals (Sweden)

    Mario Alejandro Perez Rincon

    2013-04-01

    Full Text Available The current model of water resources management in Brazil is decentralized, participative and integrated, and adopted the river basin as a planning unit. It is based on the performance of watershed committees; each committee has its own composition and rules of procedure, governed by its statute. The basic principles of this management have been established by the Brazilian Constitution of 1988 and detailed by the National Water Resources Policy in 1997. At the State level, São Paulo enacted its water resources policy in 1991. This paper examined the participatory process in basin committees of the São Paulo State and its implications in the implementation of the instruments of water management, based in a case study of the Tiete - Jacaré Watershed Committee, using questionnaires filled by the Committee’s members (2009 - 2011. Engagement and integration among the stakeholders was observed. Still, the interviews’ results have shown that the Committee’s statute should be reviewed due to differences between the Federal and the State legislation, mainly regarding the participating sectors and representatives. It also showed a need for more information about water resource issues in this basin and in the State of São Paulo, as a whole. At the same time, it is recommended that representativeness of the institutions within the water council management be improved and that the work produced by the technical chambers be recognised at the committee decision-making level.

  17. Impact of Yangtze river water transfer on the water quality of the Lixia river watershed, China.

    Science.gov (United States)

    Ma, Xiaoxue; Wang, Lachun; Wu, Hao; Li, Na; Ma, Lei; Zeng, Chunfen; Zhou, Yi; Yang, Jun

    2015-01-01

    To improve water quality and reduce the negative impacts of sudden inputs of water pollution in the Lixia River watershed, China, a series of experimental water transfers from the Yangtze River to the Lixia River were conducted from 2 December 2006 to 7 January 2007. Water samples were collected every six days at 55 monitoring sites during this period. Eight water parameters (water temperature, pH, dissolved oxygen (DO), chemical oxygen demand (COD), potassium permanganate index (CODMn), ammonia nitrogen (NH4+-N), electrical conductivity (EC), and water transparency (WT)) were analyzed to determine changes in nutrient concentrations during water transfers. The comprehensive pollution index (Pi) and single-factor (Si) evaluation methods were applied to evaluate spatio-temporal patterns of water quality during water transfers. Water quality parameters displayed different spatial and temporal distribution patterns within the watershed. Water quality was improved significantly by the water transfers, especially for sites closer to water intake points. The degree of improvement is positively related to rates of transfer inflow and drainage outflow. The effects differed for different water quality parameters at each site and at different water transfer times. There were notable decreases in NH4+-N, DO, COD, and CODMn across the entire watershed. However, positive effects on EC and pH were not observed. It is concluded that freshwater transfers from the Yangtze River can be used as an emergency measure to flush pollutants from the Lixia River watershed. Improved understanding of the effects of water transfers on water quality can help the development and implementation of effective strategies to improve water quality within this watershed.

  18. Payments for Ecosystem Services for watershed water resource allocations

    Science.gov (United States)

    Fu, Yicheng; Zhang, Jian; Zhang, Chunling; Zang, Wenbin; Guo, Wenxian; Qian, Zhan; Liu, Laisheng; Zhao, Jinyong; Feng, Jian

    2018-01-01

    Watershed water resource allocation focuses on concrete aspects of the sustainable management of Ecosystem Services (ES) that are related to water and examines the possibility of implementing Payment for Ecosystem Services (PES) for water ES. PES can be executed to satisfy both economic and environmental objectives and demands. Considering the importance of calculating PES schemes at the social equity and cooperative game (CG) levels, to quantitatively solve multi-objective problems, a water resources allocation model and multi-objective optimization are provided. The model consists of three modules that address the following processes: ① social equity mechanisms used to study water consumer associations, ② an optimal decision-making process based on variable intervals and CG theory, and ③ the use of Shapley values of CGs for profit maximization. The effectiveness of the proposed methodology for realizing sustainable development was examined. First, an optimization model with water allocation objective was developed based on sustainable water resources allocation framework that maximizes the net benefit of water use. Then, to meet water quality requirements, PES cost was estimated using trade-off curves among different pollution emission concentration permissions. Finally, to achieve equity and supply sufficient incentives for water resources protection, CG theory approaches were utilized to reallocate PES benefits. The potential of the developed model was examined by its application to a case study in the Yongding River watershed of China. Approximately 128 Mm3 of water flowed from the upper reach (Shanxi and Hebei Provinces) sections of the Yongding River to the lower reach (Beijing) in 2013. According to the calculated results, Beijing should pay USD6.31 M (¥39.03 M) for water-related ES to Shanxi and Hebei Provinces. The results reveal that the proposed methodology is an available tool that can be used for sustainable development with resolving PES

  19. Ecological site-based assessments of wind and water erosion: informing accelerated soil erosion management in rangelands

    Science.gov (United States)

    Webb, Nicholas P.; Herrick, Jeffrey E.; Duniway, Michael C.

    2014-01-01

    Accelerated soil erosion occurs when anthropogenic processes modify soil, vegetation or climatic conditions causing erosion rates at a location to exceed their natural variability. Identifying where and when accelerated erosion occurs is a critical first step toward its effective management. Here we explore how erosion assessments structured in the context of ecological sites (a land classification based on soils, landscape setting and ecological potential) and their vegetation states (plant assemblages that may change due to management) can inform systems for reducing accelerated soil erosion in rangelands. We evaluated aeolian horizontal sediment flux and fluvial sediment erosion rates for five ecological sites in southern New Mexico, USA, using monitoring data and rangeland-specific wind and water erosion models. Across the ecological sites, plots in shrub-encroached and shrub-dominated vegetation states were consistently susceptible to aeolian sediment flux and fluvial sediment erosion. Both processes were found to be highly variable for grassland and grass-succulent states across the ecological sites at the plot scale (0.25 Ha). We identify vegetation thresholds that define cover levels below which rapid (exponential) increases in aeolian sediment flux and fluvial sediment erosion occur across the ecological sites and vegetation states. Aeolian sediment flux and fluvial erosion in the study area can be effectively controlled when bare ground cover is 100 cm in length is less than ~35%. Land use and management activities that alter cover levels such that they cross thresholds, and/or drive vegetation state changes, may increase the susceptibility of areas to erosion. Land use impacts that are constrained within the range of natural variability should not result in accelerated soil erosion. Evaluating land condition against the erosion thresholds identified here will enable identification of areas susceptible to accelerated soil erosion and the development of

  20. Ecological site‐based assessments of wind and water erosion: informing accelerated soil erosion management in rangelands.

    Science.gov (United States)

    Webb, Nicholas P; Herrick, Jeffrey E; Duniway, Michael C

    Accelerated soil erosion occurs when anthropogenic processes modify soil, vegetation, or climatic conditions causing erosion rates at a location to exceed their natural variability. Identifying where and when accelerated erosion occurs is a critical first step toward its effective management. Here we explored how erosion assessments structured in the context of ecological sites (a land classification based on soils, landscape setting, and ecological potential) and their vegetation states (plant assemblages that may change due to management) can inform systems for reducing accelerated soil erosion in rangelands. We evaluated aeolian horizontal sediment flux and fluvial sediment erosion rates for five ecological sites in southern New Mexico, USA, using monitoring data and rangeland-specific wind and water erosion models. Across the ecological sites, plots in shrub-encroached and shrub-dominated vegetation states were consistently susceptible to aeolian sediment flux and fluvial sediment erosion. Both processes were found to be highly variable for grassland and grass–succulent states across the ecological sites at the plot scale (0.25 ha). We identified vegetation thresholds that define cover levels below which rapid (exponential) increases in aeolian sediment flux and fluvial sediment erosion occur across the ecological sites and vegetation states. Aeolian sediment flux and fluvial erosion in the study area could be effectively controlled when bare ground cover was 100 cm in length was less than ∼35%. Land use and management activities that alter cover levels such that they cross thresholds, and/or drive vegetation state changes, may increase the susceptibility of areas to erosion. Land use impacts that are constrained within the range of natural variability should not result in accelerated soil erosion. Evaluating land condition against the erosion thresholds identified here will enable identification of areas susceptible to accelerated soil erosion and the

  1. Topographical characteristics and evaluating water quality in watershed management

    Directory of Open Access Journals (Sweden)

    Teresa Cristina Tarlé Pissarra

    2008-09-01

    Full Text Available Topographical characteristics and water quality were evaluated at Hacienda Gloria, in Jaboticabal, São Paulo State, Brazil. Un-derstanding the relief’s morphometric characteristics and the course of the streams in a small watershed supported the hypothesis that land-use affects water quality and helps predict how changes in water-flow and the surrounding landscape occur; areas protected by native forest and those dedicated to agriculture were considered. Water quality was sampled at six sites and physical and chemical changes were analysed. Monthly water samples were collected from the streams on the same day of each month during the course of a year; Horiba equipment was used for recording data. One-way analysis of variance (ANOVA was used for determining differences between the sites being investigated. Analysing the data revealed significant differences in pH, electric conductivity, turbidity, dissolved oxygen and temperature. Topographical characteristics have been influenced by agricultural activity, thereby having an environmental impact. Surface runoff was predominant on steep slopes, mainly in areas near the top of the watershed. Land-use has had a significant impact on many physical parameters, including stream turbidity and tem-perature which increased with deforestation. The results indicated the agricultural watershed’s fragility to pollutant exposure and/ or toxicity, mainly due to turbidity in the streams caused by soil erosion, waste discharge and runoff.

  2. Research on Coupling Method of Watershed Initial Water Rights Allocation in Daling River

    Science.gov (United States)

    Liu, J.; Fengping, W.

    2016-12-01

    Water scarcity is now a common occurrence in many countries. The situation of watershed initial water rights allocation has caused many benefit conflicts among regions and regional water sectors of domestic and ecology environment and industries in China. This study aims to investigate the method of watershed initial water rights allocation in the perspective of coupling in Daling River Watershed taking provincial initial water rights and watershed-level governmental reserved water as objects. First of all, regarding the allocation subsystem of initial water rights among provinces, this research calculates initial water rights of different provinces by establishing the coupling model of water quantity and quality on the principle of "rewarding efficiency and penalizing inefficiency" based on the two control objectives of water quantity and quality. Secondly, regarding the allocation subsystem of watershed-level governmental reserved water rights, the study forecasts the demand of watershed-level governmental reserved water rights by the combination of case-based reasoning and water supply quotas. Then, the bilaterally coupled allocation model on water supply and demand is designed after supply analysis to get watershed-level governmental reserved water rights. The results of research method applied to Daling River Watershed reveal the recommended scheme of watershed initial water rights allocation based on coordinated degree criterion. It's found that the feasibility of the iteration coupling model and put forward related policies and suggestions. This study owns the advantages of complying with watershed initial water rights allocation mechanism and meeting the control requirements of water quantity, water quality and water utilization efficiency, which help to achieve the effective allocation of water resources.

  3. Watershed land use effects on lake water quality in Denmark

    DEFF Research Database (Denmark)

    Nielsen, Anders; Trolle, Dennis; Søndergaard, Martin

    2012-01-01

    Mitigating nutrient losses from anthropogenic nonpoint sources is today of particular importance for improving the water quality of numerous freshwater lakes worldwide. Several empirical relationships between land use and in-lake water quality variables have been developed, but they are often weak......, which can in part be attributed to lack of detailed information about land use activities or point sources. We examined a comprehensive data set comprising land use data, point-source information, and in-lake water quality for 414 Danish lakes. By excluding point-source-influenced lakes (n = 210....... Relationships between TP and agricultural land use were even stronger for lakes with rivers in their watershed (55%) compared to lakes without (28%), indicating that rivers mediate a stronger linkage between landscape activity and lake water quality by providing a “delivery” mechanism for excess nutrients...

  4. Fecal Contamination in the Surface Waters of a Rural- and an Urban-Source Watershed

    DEFF Research Database (Denmark)

    Stea, Emma C.; Hansen, Lisbeth Truelstrup; Jamieson, Rob C.

    2015-01-01

    , Salmonella spp., and Campylobacter spp. [C. jejuni, C. lari and C. coli]), water quality (turbidity, temperature, E. coli), and human and ruminant/cow Bacteroidales and mitochondrial DNA-based fecal source tracking (FST) markers in two source watersheds. Water samples (n=329) were collected at 10 sites (5...... in each watershed) over 18 months. The human Bacteroidales marker (HF183) occurred in 9-10% of the water samples at nine sampling sites; while a forested site in the urban watershed tested negative. Ruminant/cow Bacteroidales markers (BacR and CowM2) only appeared in the rural watershed (6%). The mtDNA...

  5. Research on Coupling Method of Watershed Initial Water Rights Allocation in Daling River

    Science.gov (United States)

    Liu, Jinhua; Wu, Fengping

    2017-05-01

    As a typical abnormal, nonlinear and multidimensional system decision-making problem, watershed initial water rights allocation involves various resource distribution, economic, social and environment objectives. Because of the large subjectivity of weight determination, different from the traditional methods, we adopt a new coupling method which is a dimension reduction method in this study to solve the watershed initial water rights allocation problem. The data allocated in Daling watershed can be calculated in optimum projection direction to gain the watershed initial water rights allocation scheme in low-dimensional space.

  6. Fena Valley Reservoir watershed and water-balance model updates and expansion of watershed modeling to southern Guam

    Science.gov (United States)

    Rosa, Sarah N.; Hay, Lauren E.

    2017-12-01

    In 2014, the U.S. Geological Survey, in cooperation with the U.S. Department of Defense’s Strategic Environmental Research and Development Program, initiated a project to evaluate the potential impacts of projected climate-change on Department of Defense installations that rely on Guam’s water resources. A major task of that project was to develop a watershed model of southern Guam and a water-balance model for the Fena Valley Reservoir. The southern Guam watershed model provides a physically based tool to estimate surface-water availability in southern Guam. The U.S. Geological Survey’s Precipitation Runoff Modeling System, PRMS-IV, was used to construct the watershed model. The PRMS-IV code simulates different parts of the hydrologic cycle based on a set of user-defined modules. The southern Guam watershed model was constructed by updating a watershed model for the Fena Valley watersheds, and expanding the modeled area to include all of southern Guam. The Fena Valley watershed model was combined with a previously developed, but recently updated and recalibrated Fena Valley Reservoir water-balance model.Two important surface-water resources for the U.S. Navy and the citizens of Guam were modeled in this study; the extended model now includes the Ugum River watershed and improves upon the previous model of the Fena Valley watersheds. Surface water from the Ugum River watershed is diverted and treated for drinking water, and the Fena Valley watersheds feed the largest surface-water reservoir on Guam. The southern Guam watershed model performed “very good,” according to the criteria of Moriasi and others (2007), in the Ugum River watershed above Talofofo Falls with monthly Nash-Sutcliffe efficiency statistic values of 0.97 for the calibration period and 0.93 for the verification period (a value of 1.0 represents perfect model fit). In the Fena Valley watershed, monthly simulated streamflow volumes from the watershed model compared reasonably well with the

  7. Declining water yield from forested mountain watersheds in response to climate change and forest mesophication

    Science.gov (United States)

    Peter V. Caldwell; Chelcy F. Miniat; Katherine J. Elliott; Wayne. T. Swank; Steven T. Brantley; Stephanie H. Laseter

    2016-01-01

    Climate change and forest disturbances are threatening the ability of forested mountain watersheds to provide the clean, reliable, and abundant fresh water necessary to support aquatic ecosystems and a growing human population. Here we used 76 years of water yield, climate, and field plot vegetation measurements in six unmanaged, reference watersheds in the southern...

  8. Hydrology and water budget for a forested atlantic coastal plain watershed, South Carolina

    Science.gov (United States)

    Scott V. Harder; Devendra M Amatya; Callahan Timothy J.; Carl C. Trettin; Hakkila Jon

    2007-01-01

    Increases in timber demand and urban development in the Atlantic Coastal Plain over the past decade have motivated studies on the hydrology, water quality, and sustainable management of coastal plain watersheds. However, studies on baseline water budgets are limited for the low-lying, forested watersheds of the Atlantic Coastal Plain. The purpose of this study was to...

  9. Links between climate change, water-table depth, and water chemistry in a mineralized mountain watershed

    Science.gov (United States)

    Manning, Andrew H.; Verplanck, Philip L.; Caine, Jonathan S.; Todd, Andrew S.

    2013-01-01

    Recent studies suggest that climate change is causing rising solute concentrations in mountain lakes and streams. These changes may be more pronounced in mineralized watersheds due to the sensitivity of sulfide weathering to changes in subsurface oxygen transport. Specific causal mechanisms linking climate change and accelerated weathering rates have been proposed, but in general remain entirely hypothetical. For mineralized watersheds, a favored hypothesis is that falling water tables caused by declining recharge rates allow an increasing volume of sulfide-bearing rock to become exposed to air, thus oxygen. Here, we test the hypothesis that falling water tables are the primary cause of an increase in metals and SO4 (100-400%) observed since 1980 in the Upper Snake River (USR), Colorado. The USR drains an alpine watershed geologically and climatologically representative of many others in mineralized areas of the western U.S. Hydrologic and chemical data collected from 2005 to 2011 in a deep monitoring well (WP1) at the top of the USR watershed are utilized. During this period, both water table depths and groundwater SO4 concentrations have generally increased in the well. A numerical model was constructed using TOUGHREACT that simulates pyrite oxidation near WP1, including groundwater flow and oxygen transport in both saturated and unsaturated zones. The modeling suggests that a falling water table could produce an increase in metals and SO4 of a magnitude similar to that observed in the USR (up to 300%). Future water table declines may produce limited increases in sulfide weathering high in the watershed because of the water table dropping below the depth of oxygen penetration, but may continue to enhance sulfide weathering lower in the watershed where water tables are shallower. Advective air (oxygen) transport in the unsaturated zone caused by seasonally variable recharge and associated water table fluctuations was found to have little influence on pyrite

  10. Water balance of drained plantation watersheds in North Carolina

    Science.gov (United States)

    Johnny M. Grace; R. W. Skaggs

    2006-01-01

    A 3-year study to evaluate the effect of thinning on the hydrology of a drained loblolly pine (Pinus taeda L.) plantation was conducted in eastern North Carolina. The study utilized a paired watershed design with a 40-ha thinned watershed (WS5) and a 16-ha control watershed (WS2). Data from the field experiment conducted from 1999-2002 was used to...

  11. Watershed Fact Sheet: Improving Utah's Water Quality, Upper Sevier River Watershed

    OpenAIRE

    Extension, USU

    2012-01-01

    The Upper Sevier River watershed is located in south central Utah, within the borders of Garfield, Kane, Piute, and Iron counties. This watershed encompasses the headwaters of the Sevier River which are straddled by the mountains of the Markagunt Plateau to the west and the Paunsaugunt Plateau to the east.

  12. EPA Office of Water (OW): Clean Watersheds Needs Survey NHDPlus Indexed Dataset

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Clean Watersheds Needs Survey (CWNS) is a comprehensive assessment of the capital needs to the water quality goals set in the Clean Water Act. Every four years,...

  13. Simulation of runoff and water quality for 1990 and 2008 land use conditions in the Reedy Creek watershed, East-Central Florida

    Science.gov (United States)

    Wicklein, Shaun M.; Schiffer, Donna M.

    2002-01-01

    Hydrologic and water-quality data have been collected within the 177-square-mile Reedy Creek, Florida, watershed, beginning as early as 1939, but the data have not been used to evaluate relations among land use, hydrology, and water quality. A model of the Reedy Creek watershed was developed and applied to the period January 1990 to December 1995 to provide a computational foundation for evaluating the effects of future land-use changes on hydrology and water quality in the watershed. The Hydrological Simulation Program-Fortran (HSPF) model was used to simulate hydrology and water quality of runoff for pervious land areas, impervious land areas, and stream reaches. Six land-use types were used to characterize the hydrology and water quality of pervious and impervious land areas in the Reedy Creek watershed: agriculture, rangeland, forest, wetlands, rapid infiltration basins, and urban areas. Hydrologic routing and water-quality reactions were simulated to characterize hydrologic and water-quality processes and the movement of runoff and its constituents through the main stream channels and their tributaries. Because of the complexity of the stream system within the Reedy Creek Improvement District (RCID) (hydraulic structures, retention ponds) and the anticipated difficulty of modeling the system, an approach of calibrating the model parameters for a subset of the gaged watersheds and confirming the usefulness of the parameters by simulating the remainder of the gaged sites was selected for this study. Two sub-watersheds (Whittenhorse Creek and Davenport Creek) were selected for calibration because both have similar land use to watersheds within the RCID (with the exception of urban areas). Given the lack of available rainfall data, the hydrologic calibration of the Whittenhorse Creek and Davenport Creek sub-watersheds was considered acceptable (for monthly data, correlation coefficients, 0.86 and 0.88, and coefficients of model-fit efficiency, 0.72 and 0

  14. Nitrate Relationships between Stream Baseflow, Well Water, and Land Use in the Tomorrow-Waupaca Watershed

    OpenAIRE

    Henry Lin; Rebecca Cook; Byron Shaw

    2001-01-01

    We examined the use of stream baseflow water quality as a representative measure of mean ground water quality in the Tomorrow-Waupaca Watershed in central Wisconsin and the relationship between agricultural land use and watershed water quality. From 1997 to 1999, 38 stream sites were sampled for nitrate during winter and summer baseflow conditions. Some sites have been sampled during winter baseflow conditions since 1994. The land area contributing ground water to each stream sampling site wa...

  15. Water use and the thermoregulatory behaviour of kangaroos in arid regions: insights into the colonisation of arid rangelands in Australia by the Eastern Grey Kangaroo (Macropus giganteus).

    Science.gov (United States)

    Dawson, Terence J; McTavish, Kirsten J; Munn, Adam J; Holloway, Joanne

    2006-01-01

    The Eastern Grey Kangaroo (Macropus giganteus) occurs mostly in the wetter regions of eastern Australia. However, in the past 30-40 years it has moved into more arid regions (rainfall Kangaroo (Macropus rufus). An increased access to water (supplied for domestic stock) may explain this range extension, but changes in the availability of preferred feed could also be involved. The water use, drinking patterns and thermoregulatory behaviour of these two species of kangaroo have been examined in a semi-free range study, during summer at an arid rangeland site. Foraging was largely nocturnal in both species and during the day they behaved to reduce heat loads. This was especially so for M. giganteus, which showed greater shade seeking. However, it still used more water (72 +/- 2.6 mL kg(-1) day(-1), mean +/- SE) than M. rufus (56 +/- 7.6 mL kg(-1) day(-1)) and drank twice as frequently. Although M. giganteus produced a less concentrated urine (1422 +/- 36 mosmol kg(-1)) than M. rufus (1843 +/- 28 mosmol kg(-1)), kidney physiology did not explain all of the differences in water metabolism between the species. Water from the feed and faecal water retention also appear to be involved. Broadly, a better access to reliable water and the utilisation of mesic microhabitats has enabled M. giganteus to make inroads into the changing rangelands of eastern Australia. However, changes in the vegetation, due to stock grazing, have also favoured M. giganteus, which is a grass eating specialist.

  16. Fire impact on soil-water repellency and functioning of semi-arid croplands and rangelands: Implications for prescribed burnings and wildfires

    Science.gov (United States)

    Stavi, Ilan; Barkai, Daniel; Knoll, Yaakov M.; Glion, Hiam Abu; Katra, Itzhak; Brook, Anna; Zaady, Eli

    2017-03-01

    An unintended fire outbreak during summer 2015 in the semi-arid Israeli Negev resulted in the burning of extensive croplands and rangelands. The rangelands have been managed over the long term for occasional grazing, while the croplands have been utilized for rainfed wheat cropping. Yet, during the studied year, the croplands were left fallow, allowing the growth of herbaceous vegetation, which was harvested and baled for hay before the fire outbreak. The study objectives were to investigate the impacts of fire, land-use, and soil depth on water-repellency and on the status and dynamics of some of the most important organic and mineral soil resources. Additionally, we aimed to assess the severity of this fire outbreak. The soil-water repellency was studied by measuring the soil's water drop penetration time (WDPT) and critical surface tension (CST). A significant effect of fire on soil hydrophobicity was recorded, with a slight increase in mean WDPT and a slight decrease in mean CST in the burnt sites than in the non-burnt sites. Yet, soil hydrophobicity in the burnt lands was rather moderate and remained within the water repellency's lowest class. A significant effect of land-use on the means of WDPT and CST was also recorded, being eleven-fold greater and 7% smaller, respectively, in the rangelands than in the croplands. This is consistent with the almost eightfold greater mean above-ground biomass recorded in the non-burnt rangelands than in the non-burnt post-harvest croplands, revealing the positive relations between available fuel load and soil-water repellency. The effect of soil depth was significant for CST but not for WDPT. Overall, the gathered data suggest that fire severity was low to moderate. Fire was also found to significantly affect the organic carbon and ammonium-N were also studied, and generally showed higher values for the burnt lands. Overall, this study shows that the low- to moderate-fire severity only slightly increased the soil water

  17. Geospatial datasets for assessing the effects of rangeland conditions on dissolved-solids yields in the Upper Colorado River Basin

    Science.gov (United States)

    Tillman, Fred D; Flynn, Marilyn E.; Anning, David W.

    2015-01-01

    In 2009, the U.S. Geological Survey (USGS) developed a Spatially Referenced Regressions on Watershed Attributes (SPARROW) surface-water quality model for the Upper Colorado River Basin (UCRB) relating dissolved-solids sources and transport in the 1991 water year to upstream catchment characteristics. The SPARROW model focused on geologic and agricultural sources of dissolved solids in the UCRB and was calibrated using water-year 1991 dissolved-solids loads from 218 monitoring sites. A new UCRB SPARROW model is planned that will update the investigation of dissolved-solids sources and transport in the basin to circa 2010 conditions and will improve upon the 2009 model by incorporating more detailed information about agricultural-irrigation and rangeland-management practices, among other improvements. Geospatial datasets relating to circa 2010 rangeland conditions are required for the new UCRB SPARROW modeling effort. This study compiled geospatial datasets for the UCRB that relate to the biotic alterations and rangeland conditions of grazing, fire and other land disturbance, and vegetation type and cover. Datasets representing abiotic alterations of access control (off-highway vehicles) and sediment generation and transport in general, were also compiled. These geospatial datasets may be tested in the upcoming SPARROW model to better understand the potential contribution of rangelands to dissolved-solids loading in UCRB streams.

  18. Watershed Fact Sheet: Improving Utah's Water Quality, Middle and Lower Sevier Watershed

    OpenAIRE

    Extension, USU

    2012-01-01

    The Middle and Lower Sevier watershed includes all of the basins of the Middle and Lower Sevier River, and is located in all or parts of Piute, Sevier, Sanpete, Juab, Millard, Tooele and Beaver counties.

  19. Nitrate Relationships between Stream Baseflow, Well Water, and Land Use in the Tomorrow-Waupaca Watershed

    Directory of Open Access Journals (Sweden)

    Henry Lin

    2001-01-01

    Full Text Available We examined the use of stream baseflow water quality as a representative measure of mean ground water quality in the Tomorrow-Waupaca Watershed in central Wisconsin and the relationship between agricultural land use and watershed water quality. From 1997 to 1999, 38 stream sites were sampled for nitrate during winter and summer baseflow conditions. Some sites have been sampled during winter baseflow conditions since 1994. The land area contributing ground water to each stream sampling site was delineated, resulting in 38 sub-basins. In addition, over 3500 test results from private wells in the watershed were compiled and mapped using a Geographic Information System (GIS. Nitrate concentrations in stream baseflow and well waters were found to have strong positive correlation in the sub-basins of second order or higher. This indicates that stream baseflow may be valid for monitoring mean ground water quality in watersheds predominantly fed by ground water, where much of the stream nitrate is believed to originate from ground water. Analysis of seasonal variation in the stream data showed that winter nitrate concentrations were higher than summer concentrations, implying that winter stream monitoring may be more critical for the assessment of overall ground water quality in the watershed. We also found that, as the amount of agricultural land increased in each sub-basin, average nitrate concentrations in the well and stream waters also increased, suggesting a connection between agricultural land use and nitrate contamination of water resources in the watershed.

  20. Assessing the radar rainfall estimates in watershed-scale water quality model

    Science.gov (United States)

    Watershed-scale water quality models are effective science-based tools for interpreting change in complex environmental systems that affect hydrology cycle, soil erosion and nutrient fate and transport in watershed. Precipitation is one of the primary input data to achieve a precise rainfall-runoff ...

  1. DRAINMOD-GIS: a lumped parameter watershed scale drainage and water quality model

    Science.gov (United States)

    G.P. Fernandez; G.M. Chescheir; R.W. Skaggs; D.M. Amatya

    2006-01-01

    A watershed scale lumped parameter hydrology and water quality model that includes an uncertainty analysis component was developed and tested on a lower coastal plain watershed in North Carolina. Uncertainty analysis was used to determine the impacts of uncertainty in field and network parameters of the model on the predicted outflows and nitrate-nitrogen loads at the...

  2. Contrasting nitrogen and phosphorus budgets in urban watersheds and implications for managing urban water pollution.

    Science.gov (United States)

    Hobbie, Sarah E; Finlay, Jacques C; Janke, Benjamin D; Nidzgorski, Daniel A; Millet, Dylan B; Baker, Lawrence A

    2017-04-18

    Managing excess nutrients remains a major obstacle to improving ecosystem service benefits of urban waters. To inform more ecologically based landscape nutrient management, we compared watershed inputs, outputs, and retention for nitrogen (N) and phosphorus (P) in seven subwatersheds of the Mississippi River in St. Paul, Minnesota. Lawn fertilizer and pet waste dominated N and P inputs, respectively, underscoring the importance of household actions in influencing urban watershed nutrient budgets. Watersheds retained only 22% of net P inputs versus 80% of net N inputs (watershed area-weighted averages, where net inputs equal inputs minus biomass removal) despite relatively low P inputs. In contrast to many nonurban watersheds that exhibit high P retention, these urban watersheds have high street density that enhanced transport of P-rich materials from landscapes to stormwater. High P exports in storm drainage networks and yard waste resulted in net P losses in some watersheds. Comparisons of the N/P stoichiometry of net inputs versus storm drain exports implicated denitrification or leaching to groundwater as a likely fate for retained N. Thus, these urban watersheds exported high quantities of N and P, but via contrasting pathways: P was exported primarily via stormwater runoff, contributing to surface water degradation, whereas N losses additionally contribute to groundwater pollution. Consequently, N management and P management require different strategies, with N management focusing on reducing watershed inputs and P management also focusing on reducing P movement from vegetated landscapes to streets and storm drains.

  3. Contrasting nitrogen and phosphorus budgets in urban watersheds and implications for managing urban water pollution

    Science.gov (United States)

    Janke, Benjamin D.; Nidzgorski, Daniel A.; Millet, Dylan B.; Baker, Lawrence A.

    2017-01-01

    Managing excess nutrients remains a major obstacle to improving ecosystem service benefits of urban waters. To inform more ecologically based landscape nutrient management, we compared watershed inputs, outputs, and retention for nitrogen (N) and phosphorus (P) in seven subwatersheds of the Mississippi River in St. Paul, Minnesota. Lawn fertilizer and pet waste dominated N and P inputs, respectively, underscoring the importance of household actions in influencing urban watershed nutrient budgets. Watersheds retained only 22% of net P inputs versus 80% of net N inputs (watershed area-weighted averages, where net inputs equal inputs minus biomass removal) despite relatively low P inputs. In contrast to many nonurban watersheds that exhibit high P retention, these urban watersheds have high street density that enhanced transport of P-rich materials from landscapes to stormwater. High P exports in storm drainage networks and yard waste resulted in net P losses in some watersheds. Comparisons of the N/P stoichiometry of net inputs versus storm drain exports implicated denitrification or leaching to groundwater as a likely fate for retained N. Thus, these urban watersheds exported high quantities of N and P, but via contrasting pathways: P was exported primarily via stormwater runoff, contributing to surface water degradation, whereas N losses additionally contribute to groundwater pollution. Consequently, N management and P management require different strategies, with N management focusing on reducing watershed inputs and P management also focusing on reducing P movement from vegetated landscapes to streets and storm drains. PMID:28373560

  4. Storms do not alter long-term watershed development influences on coastal water quality.

    Science.gov (United States)

    Chen, Yushun; Cebrian, Just; Lehrter, John; Christiaen, Bart; Stutes, Jason; Goff, Josh

    2017-09-15

    A twelve year (2000-2011) study of three coastal lagoons in the Gulf of Mexico was conducted to assess the impacts of local watershed development and tropical storms on water quality. The lagoons have similar physical and hydrological characteristics, but differ substantially in the degree of watershed urban development and nutrient loading rates. In total the lagoons experienced 22 storm events during the period studied. Specifically, we examine (1) whether there are influences on water quality in the lagoons from watershed development, (2) whether there are influences on water quality in the lagoons from storm activity, and (3) whether water quality is affected to a greater degree by watershed development versus storm activity. The two urbanized lagoons typically showed higher water-column nitrate, dissolved organic nitrogen, and phosphate compared with the non-urbanized lagoon. One of the urbanized lagoons had higher water-column chlorophyll a concentrations than the other two lagoons on most sampling dates, and higher light extinction coefficients on some sampling dates. The non-urbanized lagoon had higher water-column dissolved oxygen concentrations than other lagoons on many sampling dates. Our results suggest long-term influences of watershed development on coastal water quality. We also found some evidence of significant storm effects on water quality, such as increased nitrate, phosphate, and dissolved oxygen, and decreased salinity and water temperature. However, the influences of watershed development on water quality were greater. These results suggest that changes in water quality induced by human watershed development pervade despite the storm effects. These findings may be useful for environmental management since they suggest that storms do not profoundly alter long-term changes in water quality that resulted from human development of watersheds. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Characterizing changing stream water quality in a glacierized tropical watershed

    Science.gov (United States)

    Mark, B. G.; Eddy, A. M.; Baraer, M.; McKenzie, J. M.; Walsh, E.; Fernandez, A.; Wigmore, O.; Battista, R.; Guittard, A.

    2013-12-01

    Glacier recession in the Cordillera Blanca, Peru has been causing downstream hydrologic transformations, altering the amount, timing and chemical quality of stream water. Increased demand from multiple water resource users, particularly industrial-scale agricultural irrigation along the desert coast, underscores the need for accurate source attribution and treatment of pollutants. Water quality assessment is challenging given natural geologic controls on water chemistry concentrations, and a lack of consistent historical monitoring. Here we present results from an analytical characterization of spatial and temporal variability in the dissolved loads of major ions, isotopes and select trace metals in the Pacific-draining Santa River and tributaries. Our approach incorporates multi-year synoptic sampling of water chemistry and stream discharge along the river course and at tributary pour points, along with weekly sampling at single point along the upper Santa. Samples were taken predominately during the austral winter months of June, July, and August in 2004 - 2009 and 2011 - 2013 at 20-30 stream localities. Digitized maps of geology, land use and hydrography permit geographic visualization and exploratory GIS-based data analysis. Results indicate that the dominant hydrochemical processes throughout the Santa watershed include silicate weathering, coupled pyrite oxidation with silicate weathering, and to a lesser extent, carbonate weathering. Low pH and high concentrations of sulfate are found in the presence of high-silica granitic and metamorphic surface lithology in some sites proximal to receding glaciers, reflecting an environment that is driven by coupled sulfide-oxidation and silicate dissolution. Numerous sites had elevated concentrations of trace metals (such as As, Cd, and Pb) indicating potential local sources of contamination, some in excess of World Health Organization. Weekly sampling show dilution of certain trace metals during the wet season, and

  6. Export of Dissolved Organic Carbon following Prescribed Fire on Forested Watersheds: Implications for Watershed Management for Drinking Water Supply

    Science.gov (United States)

    Zhang, W.; Olivares, C. I.; Uzun, H.; Erdem, C. U.; Trettin, C.; Liu, Y.; Robinson, E. R.; Karanfil, T.; Chow, A. T.

    2016-12-01

    Detrital material in forest watersheds is the major terrestrial source of dissolved organic matter (DOM) and disinfection byproduct (DBP) precursors in surface source waters, but it is also the fuel for forest fires. Prescribed fire, as a fuel reduction technique is intended to reduce the amount of forest detritus, and therefore the risk of wildfire. Accordingly, periodic prescribed fire can reduce the accumulation of detritus on forest floor and the amount of DOM export after forest treatments. To evaluate the effects of prescribed fire on water quality, we conducted a controlled study on a paired first-order watershed system that includes a 160 ha treatment watershed (WS77) and 200 ha control watershed (WS80) on the Santee Experimental Forest, near Charleston South Carolina. WS77 has been used for prescribed fire research since the 1960's, the current experimental burn occurred on April, 2016. WS80 has not been managed or burned for at least 55 years. Gauging stations were equipped with in-situ TOC sensors and flow-proportional water samplers for monitoring temporal trends on water quality. Water samples taken from the first runoff event from both watersheds including rising limb, peak discharge, and falling limb were used for detailed chemical characterizations including DOC and nutrient concentrations, coagulation efficiency, and DBP formation such as trihalomethanes (THMs) and halocacetic acids (HAAs) from chlorination as well as N-nitrosodimethylamine (NDMA) from chlorination, and chemical formula assignment on DOM using Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (FT-ICR-MS) before and after chlorination and chloramination. Preliminary FT-ICR-MS data shows that DOM chemical compositions are different between raw samples collected from WS77 and WS80. Chlorination resulted in a shift toward lower molecular mass compared to the raw materials. While chloramination did not cause a drastic mass shift, such a treatment also produced DOM moieties

  7. Assessment of runoff water quality for an integrated best-management practice system in an agricultural watershed

    Science.gov (United States)

    To better understand, implement and integrate best management practices (BMPs) in agricultural watersheds, critical information on their effectiveness is required. A representative agricultural watershed, Beasley Lake, was used to compare runoff water quality draining through an integrated system of...

  8. Contribution to surface water contamination understanding by pesticides and pharmaceuticals, at a watershed scale.

    Science.gov (United States)

    Piel, Stéphanie; Baurès, Estelle; Thomas, Olivier

    2012-12-04

    This study aims at understanding the presence of regulated and emerging micropollutants, particularly pesticides and pharmaceuticals, in surface water, regarding spatial and temporal influences at a watershed scale. The study of relations between micropollutants and other water quality and hydroclimatic parameters was carried out from a statistical analysis on historical and experimental data of different sampling sites from the main watershed of Brittany, western France. The outcomes point out the influence of urban and rural areas of the watershed as well as the impact of seasons on contamination variations. This work contributes to health risk assessment related to surface water contamination by micropollutants. This approach is particularly interesting in the case of agricultural watersheds such as the one studied, where more than 80% of surface water is used to produce drinking water.

  9. Contribution to Surface Water Contamination Understanding by Pesticides and Pharmaceuticals, at a Watershed Scale

    Directory of Open Access Journals (Sweden)

    Stéphanie Piel

    2012-12-01

    Full Text Available This study aims at understanding the presence of regulated and emerging micropollutants, particularly pesticides and pharmaceuticals, in surface water, regarding spatial and temporal influences at a watershed scale. The study of relations between micropollutants and other water quality and hydroclimatic parameters was carried out from a statistical analysis on historical and experimental data of different sampling sites from the main watershed of Brittany, western France. The outcomes point out the influence of urban and rural areas of the watershed as well as the impact of seasons on contamination variations. This work contributes to health risk assessment related to surface water contamination by micropollutants. This approach is particularly interesting in the case of agricultural watersheds such as the one studied, where more than 80% of surface water is used to produce drinking water.

  10. Water temperature in irrigation return flow from the Upper Snake Rock watershed

    Science.gov (United States)

    Water returning to a river from an irrigated watershed could increase the water temperature in the river. The objective of this study was to compare the temperature of irrigation return flow water with the temperature of the diverted irrigation water. Water temperature was measured weekly in the mai...

  11. Impacts of surface water diversions for marijuana cultivation on aquatic habitat in four northwestern California watersheds.

    Directory of Open Access Journals (Sweden)

    Scott Bauer

    Full Text Available Marijuana (Cannabis sativa L. cultivation has proliferated in northwestern California since at least the mid-1990s. The environmental impacts associated with marijuana cultivation appear substantial, yet have been difficult to quantify, in part because cultivation is clandestine and often occurs on private property. To evaluate the impacts of water diversions at a watershed scale, we interpreted high-resolution aerial imagery to estimate the number of marijuana plants being cultivated in four watersheds in northwestern California, USA. Low-altitude aircraft flights and search warrants executed with law enforcement at cultivation sites in the region helped to validate assumptions used in aerial imagery interpretation. We estimated the water demand of marijuana irrigation and the potential effects water diversions could have on stream flow in the study watersheds. Our results indicate that water demand for marijuana cultivation has the potential to divert substantial portions of streamflow in the study watersheds, with an estimated flow reduction of up to 23% of the annual seven-day low flow in the least impacted of the study watersheds. Estimates from the other study watersheds indicate that water demand for marijuana cultivation exceeds streamflow during the low-flow period. In the most impacted study watersheds, diminished streamflow is likely to have lethal or sub-lethal effects on state- and federally-listed salmon and steelhead trout and to cause further decline of sensitive amphibian species.

  12. Critical level of water recharges in the catchment areas of Manna watershed Bengkulu Province Indonesia

    Science.gov (United States)

    Amri, Khairul; Nugraha, Loparedo; Barchia, Muhammad Faiz

    2017-11-01

    Land use changes in Manna watershed are caused degradation in the watershed functions. When water infiltration goes down, some water runs off flowing to Manna River cause submerged on the downstream. The aim of this study is to analyze how the Manna watershed overcoming environmentally degraded conditions. The critical level of the Manna catchment areas was determined by overlaying some digital maps based on procedure applying in the Ministry of Forestry, Republic of Indonesia (P.32/MENHUT-II/2009). Measuring the critical level of the catchment also needed natural and actual infiltrations map, and the interpretation process of the analysis used ArcGIS 10.1 software. Based on the spatial data analysis by overlaying maps of slope, soils, and rainfall, the natural infiltration rate in the Manna watershed categorized high level (44.1%). While, the critical level of the catchment areas of the Manna watershed classified in good condition cover about 64,5 % of the areas, and starting to degraded state cover about 35,5 % of the watershed areas. The environment degradation conditions indicated the land use changes in the Manna watershed could deteriorate infiltration rates. The cultivated agricultural activities neglected conservation rule could accelerate the critical catchment areas in the Manna watershed.

  13. EPA acknowledges federal, state and local partners for Improving Water Quality in the Bear Creek Watershed

    Science.gov (United States)

    ATLANTA - The U.S. Environmental Protection Agency (EPA) commends the efforts of the Alabama Department of Environmental Management (ADEM) along with other federal, state and local partners for improving water quality in the Bear Creek Watershed.

  14. Water resources of the Lac Qui Parle River Watershed, Southwestern Minnesota

    Science.gov (United States)

    Cotter, R.D.; Bidwell, L.E.

    1968-01-01

    The Lac qui Parle River watershed is underlain by thick water-bearing sections of glacial drift and Cretaceous rocks. Drainage is from the Coteau des Praries, a plateau in the southwest, to the Lac qui Parle reservoir, about 800 feet lower than the plateau. The term "watershed" as used in this report refers to that part of the drainage basin (767 square miles) within Minnesota. The total area of the drainage basin, including South Dakota, is 1110 square miles. Most waters from the watershed are of good quality.

  15. Statistical Analysis and water Quality Modeling for a Drinking Water Source Watershed for the City of Houston, Texas

    Science.gov (United States)

    Teague, A.; Bedient, P.; Vieux, B. E.

    2009-12-01

    Water quality is a problem in Lake Houston, the primary source of drinking water for the City of Houston, due to pollutant loads coming from the influent watersheds, including Cypress Creek. Water quality issues in the watershed that are of concern for the lake include nutrient enrichment bacterial impairment, both of which present operational challenges for the drinking water treatment plant operations. Statistical analysis of the historic water quality data was developed in order to understand the source characterization and seasonality of the watershed. Multivariate analysis including principal component, cluster, and discriminant analysis provided a unique seasonal assessment of the watershed leading to refined loading curves have been analyzed using data collected by the USGS at 3 sites in Cypress Creek with corresponding City of Houston water quality data at the sites for the past 5 years to characterize the behavior of the pollutant source and watershed. A VfloTM hydrologic model from Vieux & Assoc., Inc for the watershed of the influent stream Cypress Creek was developed to predict the watershed flows into Lake Houston. A distributed model of a large scale watershed, it uses finite element analysis to solve the kinematic wave equation. The model incorporates land use relationships to predict runoff from Radar rainfall data. Continuous VfloTM was run for storm events and the distributed discharge of the watershed simulated. From the spatial discharge output, nutrient wash-off and convective transport was simulated. The simulated nutrient transport was then compared to storm sampling data at a downstream location to assess the water quality model and determine needed future refinements.

  16. 76 FR 68499 - Draft WaterSMART Cooperative Watershed Management Program Funding Opportunity Announcement

    Science.gov (United States)

    2011-11-04

    ... and time. Water shortage and water-use conflicts have become more commonplace in many areas of the... Office of the Secretary Draft WaterSMART Cooperative Watershed Management Program Funding Opportunity Announcement AGENCY: Office of the Assistant Secretary for Water and Science, Interior. ACTION: Notice of...

  17. Watershed: The Role of Fresh Water in the Israeli-Palestinian Conflict

    International Development Research Centre (IDRC) Digital Library (Canada)

    Watershed describes the water crisis faced by Israel and the Occupied Palestinian Territories today — a crisis that will have much to do with the design and the success of the current peace proposals. The authors examine the geopolitics of water in the region, the economic importance, problems of water supply and water ...

  18. Watershed: The Role of Fresh Water in the Israeli-Palestinian ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Watershed describes the water crisis faced by Israel and the Occupied Palestinian Territories today — a crisis that will have much to do with the design and the success of the current peace proposals. The authors examine the geopolitics of water in the region, the economic importance, problems of water supply and water ...

  19. Water storage at the Panola Mountain Research Watershed, Georgia, USA

    Science.gov (United States)

    Peters, N.E.; Aulenbach, Brent T.

    2011-01-01

    Storage is a major component of a catchment water balance particularly when the water balance components are evaluated on short time scales, that is, less than annual. We propose a method of determining the storage-discharge relation using an exponential function and daily precipitation, potential evapotranspiration (PET) and baseflow during the dormant season when evapotranspiration (ET) is low. The method was applied to the 22-year data series of the 0.41-ha forested Panola Mountain Research Watershed, Georgia. The relation of cumulative daily precipitation minus daily runoff and PET versus baseflow was highly significant (r2=0.92, pcatchment storage range was ~400mm, averaging 219mm annually, which is attributed to contributions of soil water and groundwater. The soil moisture of a catchment average 1-m soil depth was evaluated and suggests that there was an active (changes in soil storage during stormflow) and passive (a longer-term seasonal cycle) soil water storage with ranges of 40-70 and 100-120mm, respectively. The active soil water storage was short term on the order of days during and immediately after rainstorms, and the passive or seasonal soil storage was highest during winter when ET was lowest and lowest during summer when ET was highest. An estimate of ET from daily changes in soil moisture (ETSM) during recessions was comparable with PET during the dormant season (1.5mmday-1) but was much lower during the growing season (June through August); monthly average SMET and PET ranged from 2.8 to 4.0mmday-1 and from 4.5 to 5.5mmday-1, respectively. The growing season difference is attributed to the overestimation of PET. ETSM estimates were comparable with those derived from hillslope water balances during sprinkling experiments. Master recession curves derived from the storage-discharge relation adjusted seasonally for ET (1.5 and 4.0mmday-1 during the dormant and growing seasons, respectively) fit actual recessions extremely well. ?? 2011 John Wiley

  20. Twenty years of water-quality studies in the Cheney Reservoir Watershed, Kansas, 1996-2016

    Science.gov (United States)

    Graham, Jennifer L.; Foster, Guy M.; Kramer, Ariele R.

    2017-03-31

    Since 1996, the U.S. Geological Survey (USGS), in cooperation with the City of Wichita, has done studies in the Cheney Reservoir watershed to understand environmental effects on water-quality conditions. Early studies (1996–2001) determined subwatershed sources of contaminants, nutrient and sediment loading to Cheney Reservoir, changes in reservoir sediment quality over time, and watershed sources of phosphorus. Later studies (2001–present) focused on nutrient and sediment concentrations and mass transport from the watershed; the presence of cyanobacteria, cyanotoxins, and taste-and-odor compounds in the reservoir; and development of regression models for real-time computations of water-quality constituents of interest that may affect drinking-water treatment. This fact sheet summarizes key results from studies done by the USGS during 1996–2016 in the Cheney Reservoir watershed and Cheney Reservoir.

  1. Walnut Creek Watershed Restoration and Water Quality Monitoring Project

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The primary objective of this project is to establish a nonpoint source monitoring program in relation to the watershed habitat restoration and agricultural...

  2. Bridging the gap between uncertainty analysis for complex watershed models and decision-making for watershed-scale water management

    Science.gov (United States)

    Zheng, Y.; Han, F.; Wu, B.

    2013-12-01

    Process-based, spatially distributed and dynamic models provide desirable resolutions to watershed-scale water management. However, their reliability in solving real management problems has been seriously questioned, since the model simulation usually involves significant uncertainty with complicated origins. Uncertainty analysis (UA) for complex hydrological models has been a hot topic in the past decade, and a variety of UA approaches have been developed, but mostly in a theoretical setting. Whether and how a UA could benefit real management decisions remains to be critical questions. We have conducted a series of studies to investigate the applicability of classic approaches, such as GLUE and Markov Chain Monte Carlo (MCMC) methods, in real management settings, unravel the difficulties encountered by such methods, and tailor the methods to better serve the management. Frameworks and new algorithms, such as Probabilistic Collocation Method (PCM)-based approaches, were also proposed for specific management issues. This presentation summarize our past and ongoing studies on the role of UA in real water management. Challenges and potential strategies to bridge the gap between UA for complex models and decision-making for management will be discussed. Future directions for the research in this field will also be suggested. Two common water management settings were examined. One is the Total Maximum Daily Loads (TMDLs) management for surface water quality protection. The other is integrated water resources management for watershed sustainability. For the first setting, nutrients and pesticides TMDLs in the Newport Bay Watershed (Orange Country, California, USA) were discussed. It is a highly urbanized region with a semi-arid Mediterranean climate, typical of the western U.S. For the second setting, the water resources management in the Zhangye Basin (the midstream part of Heihe Baisn, China), where the famous 'Silk Road' came through, was investigated. The Zhangye

  3. Application of GIS for Assessment of Water Availability in the Cianten Watershed, West Java

    Science.gov (United States)

    Mirrah, A. A.; Kusratmoko, E.

    2017-12-01

    Spatial information about the water availability in a region is very important in the management of sustainable water resources. Geographic information systems allows spatial information about water availability in watersheds to be assessed and monitored over time and within a predefined unit of space. This paper describes the application of GIS to assess the water availability and water demands spatially in the Cianten watershed, Bogor District, West Java. The availability of water for each sub-watershed was assessed using the water balance equation. Rainfall and temperature data for the 2007-2016 period, data of elevation, slope, soil type and land use for research area were used to calculate the water availabiliy, both annual and dry season. While the data on population size and land use were used to calculate water demands (domestic and non-domestic) for each sub-watershed based on the standards issued by the Ministry of Public Works and Agriculture. The analysis results using GIS platform shows a spatial variation of annual water availability and dry season. The water availability ranges from 9266 m3 / ha to 15,991 m3 / ha, while the dry season ranges from 2285 m3/ha to 4147 m3 / ha. Comparing water availability and water demands show that during the dry season most subwatersheds in the study area experienced a high to low water deficit.

  4. Post-reclamation water quality trend in a Mid-Appalachian watershed of abandoned mine lands.

    Science.gov (United States)

    Wei, Xinchao; Wei, Honghong; Viadero, Roger C

    2011-02-01

    Abandoned mine land (AML) is one of the legacies of historic mining activities, causing a wide range of environmental problems worldwide. A stream monitoring study was conducted for a period of 7 years to evaluate the water quality trend in a Mid-Appalachian watershed, which was heavily impacted by past coal mining and subsequently reclaimed by reforestation and revegetation. GIS tools and multivariate statistical analyses were applied to characterize land cover, to assess temporal trends of the stream conditions, and to examine the linkages between water quality and land cover. In the entire watershed, 15.8% of the land was designated as AML reclaimed by reforestation (4.9%) and revegetation (10.8%). Statistic analysis revealed sub-watersheds with similar land cover (i.e. percentage of reclaimed AML) had similar water quality and all tested water quality variables were significantly related to land cover. Based on the assessment of water quality, acid mine drainage was still the dominant factor leading to the overall poor water quality (low pH, high sulfate and metals) in the watershed after reclamation was completed more than 20 years ago. Nevertheless, statistically significant improvement trends were observed for the mine drainage-related water quality variables (except pH) in the reclaimed AML watershed. The lack of pH improvement in the watershed might be related to metal precipitation and poor buffering capacity of the impacted streams. Furthermore, water quality improvement was more evident in the sub-watersheds which were heavily impacted by past mining activities and reclaimed by reforestation, indicating good reclamation practice had positive impact on water quality over time. Copyright © 2010. Published by Elsevier B.V.

  5. Watershed boundaries for the U.S. Geological Survey National Water Quality Network

    Science.gov (United States)

    Baker, Nancy T.

    2016-01-01

    The National Water Quality Network (NWQN) for Rivers and Streams includes 113 surface-water river and stream sites monitored by the U.S. Geological Survey (USGS) National Water Quality Program (NWQP). The NWQN represents the consolidation of four historical national networks: the USGS National Water-Quality Assessment (NAWQA) Project, the USGS National Stream Quality Accounting Network (NASQAN), the National Monitoring Network (NMN), and the Hydrologic Benchmark Network (HBN). The NWQN includes 22 large river coastal sites, 41 large river inland sites, 30 wadeable stream reference sites, 10 wadeable stream urban sites, and 10 wadeable stream agricultural sites. In addition to the 113 NWQN sites, 3 large inland river monitoring sites from the USGS Cooperative Matching Funds (Co-op) program are also included in this annual water-quality reporting Web site to be consistent with previous USGS studies of nutrient transport in the Mississippi-Atchafalaya River Basin. This data release contains geo-referenced digital data and associated attributes of watershed boundaries for 113 NWQN and 3 Co-op sites. Two sites, "Wax Lake Outlet at Calumet, LA"; 07381590, and "Lower Atchafalaya River at Morgan City, LA"; 07381600, are outflow distributaries into the Gulf of Mexico. Watershed boundaries were delineated for the portion of the watersheds between "Red River near Alexandria, LA"; 07355500 and "Atchafalaya River at Melville, LA"; 07381495 to the two distributary sites respectively. Drainage area was undetermined for these two distributary sites because the main stream channel outflows into many smaller channels so that streamflow is no longer relative to the watershed area. NWQN watershed boundaries were derived from the Watershed Boundary Dataset-12-digit hydrologic units (WBD-12). The development of the WBD-12 was a coordinated effort between the United States Department of Agriculture-Natural Resources Conservation Service (USDA-NRCS), the USGS, and the Environmental

  6. A Paired watershed Evaluation of Agroforestry effects on Water Quality on a Corn/Soybean Rotation

    Science.gov (United States)

    Udawatta, Ranjith; Jose, Shibu; Garrett, Harold

    2015-04-01

    Rigorous long-term scientific studies confirming environmental benefits from the use of agroforestry practices are limited and thus limit the adoption of agroforestry practices throughout the world. The objective of the study was to examine non point source pollution (NPSP) reduction by agroforestry buffers in row-crop watersheds. The study consists of three watersheds in a paired watershed design in Knox County, Missouri, USA. Watersheds were established in 1991 and treatments of agroforestry (trees+grass) and grass buffers were established on two watersheds in 1997 after a 7-year calibration period. Runoff water samples were analyzed for sediment, total nitrogen (TN) and total phosphorus (TP) for the 2009 to 2010 period. Results indicated that agroforestry and grass buffers on row crop watersheds significantly reduce runoff, sediment, TN, and TP losses to streams. Buffers in association with row crop management reduced runoff by 26% during the study period as compared to the control treatments. Average sediment loss for row crop management and buffer watersheds was 14.8 and 9.7 kg ha-1 yr-1 respectively. On average, grass and agroforestry buffers reduced sediment, TN, and TP losses by 32, 42, and 46% compared to the control treatments. These differences could in part be attributed to the differences in management, soils, and landscape features. Results from this study strongly indicate that agroforestry and grass buffers can be implemented to reduce NPSP to water bodies while improving land value and environmental quality.

  7. Green Water Credits and Its Applications to Watershed Eco-compensation in China

    NARCIS (Netherlands)

    Bai, Z.G.

    2015-01-01

    Watershed eco-compensation is one key component of the eco-compensation framework. The green water credit is one of the eco-compensation modes. The concept of the green water credit, technical system of quantitative assessment and application of the green water credit in Kenya, Morocco and China are

  8. 78 FR 67336 - Habitat Conservation Plan for the United Water Conservation District, Santa Clara River Watershed...

    Science.gov (United States)

    2013-11-12

    ..., operations, and maintenance of water management facilities within the lower Santa Clara River watershed... water management activities. United intends to request a 50-year permit covering five species federally... describe direct, indirect, and cumulative impacts on biological resources, land use, air quality, water...

  9. Water budget considerations regarding groundwater extraction targets in the Calera Aquifer watershed, Mexico

    Science.gov (United States)

    Groundwater extraction from the Calera Aquifer in the State of Zacatecas, Mexico, for irrigation, urban, and industrial uses has increased over recent decades to unsustainable levels. An annual, watershed-scale water budget analysis was conducted to identify alternative water conservation and water...

  10. Urban stormwater – greywater management system for sustainable urban water management at sub-watershed level

    Directory of Open Access Journals (Sweden)

    Arora Amarpreet Singh

    2017-01-01

    Full Text Available Urban water management involves urban water supply (import, treatment and distribution of water, urban wastewater management (collection, treatment and disposal of urban sewage and urban storm water management. Declining groundwater tables, polluted and declining sources of water, water scarcity in urban areas, unsatisfactory urban water supply and sanitation situation, pollution of receiving water bodies (including the ground water, and urban floods have become the concerns and issues of sustainable urban water management. This paper proposes a model for urban stormwater and sewage management which addresses these concerns and issues of sustainable urban water management. This model proposes segregation of the sewage into black water and greywater, and urban sub-watershed level stormwater-greywater management systems. During dry weather this system will be handling only the greywater and making the latter available as reclaimed water for reuse in place of the fresh water supply. During wet weather, the system will be taking care of (collection and treatment both the storm water and the greywater, and the excess of the treated water will be disposed off through groundwater recharging. Application of this model in the Patiala city, Punjab, INDIA for selected urban sub-watersheds has been tried. Information and background data required for the conceptualization and design of the sub-watershed level urban stormwater-greywater management system was collected and the system has been designed for one of the sub-watersheds in the Patiala city. In this paper, the model for sustainable urban water management and the design of the Sub-watershed level Urban Stormwater-Greywater Management System are described.

  11. Urban stormwater - greywater management system for sustainable urban water management at sub-watershed level

    Science.gov (United States)

    Singh Arora, Amarpreet

    2017-11-01

    Urban water management involves urban water supply (import, treatment and distribution of water), urban wastewater management (collection, treatment and disposal of urban sewage) and urban storm water management. Declining groundwater tables, polluted and declining sources of water, water scarcity in urban areas, unsatisfactory urban water supply and sanitation situation, pollution of receiving water bodies (including the ground water), and urban floods have become the concerns and issues of sustainable urban water management. This paper proposes a model for urban stormwater and sewage management which addresses these concerns and issues of sustainable urban water management. This model proposes segregation of the sewage into black water and greywater, and urban sub-watershed level stormwater-greywater management systems. During dry weather this system will be handling only the greywater and making the latter available as reclaimed water for reuse in place of the fresh water supply. During wet weather, the system will be taking care of (collection and treatment) both the storm water and the greywater, and the excess of the treated water will be disposed off through groundwater recharging. Application of this model in the Patiala city, Punjab, INDIA for selected urban sub-watersheds has been tried. Information and background data required for the conceptualization and design of the sub-watershed level urban stormwater-greywater management system was collected and the system has been designed for one of the sub-watersheds in the Patiala city. In this paper, the model for sustainable urban water management and the design of the Sub-watershed level Urban Stormwater-Greywater Management System are described.

  12. Hydrology and water quality of two first order forested watersheds in coastal South Carolina

    Science.gov (United States)

    D.M. Amatya; M. Miwa; C.A. Harrison; C.C. Trettin; G. Sun

    2006-01-01

    Two first-order forested watersheds (WS 80 and WS 77) on poorly drained pine-hardwood stands in the South Carolina Coastal Plain have been monitored since mid-1960s to characterize the hydrology, water quality and vegetation dynamics. This study examines the flow and nutrient dynamics of these two watersheds using 13 years (1 969-76 and 1977-81) of data prior to...

  13. South Fork Iowa River watershed selected for a national water-quality study

    Science.gov (United States)

    Erwin, M.L.; Kalkhoff, Stephen

    2005-01-01

    The U.S. Geological Survey (USGS) is studying seven watersheds across the Nation to better understand how natural factors and agricultural management practices (AMPs) affect the transport of water and chemicals. Natural factors include climate and landscape (soil type, topography, geology), and AMPs include practices related to tillage, irrigation, and chemical application. The study approach is similar in each watershed so that we can compare and contrast the results and more accurately predict conditions in other agricultural settings.

  14. Microbiological evaluation of water quality from urban watersheds for domestic water supply improvement.

    Science.gov (United States)

    Ibekwe, A Mark; Murinda, Shelton E; Graves, Alexandria K

    2011-12-01

    Agricultural and urban runoffs may be major sources of pollution of water bodies and major sources of bacteria affecting the quality of drinking water. Of the different pathways by which bacterial pathogens can enter drinking water, this one has received little attention to date; that is, because soils are often considered to be near perfect filters for the transport of bacterial pathogens through the subsoil to groundwater. The goals of this study were to determine the distribution, diversity, and antimicrobial resistance of pathogenic Escherichia coli isolates from low flowing river water and sediment with inputs from different sources before water is discharged into ground water and to compare microbial contamination in water and sediment at different sampling sites. Water and sediment samples were collected from 19 locations throughout the watershed for the isolation of pathogenic E. coli. Heterotrophic plate counts and E. coli were also determined after running tertiary treated water through two tanks containing aquifer sand material. Presumptive pathogenic E. coli isolates were obtained and characterized for virulent factors and antimicrobial resistance. None of the isolates was confirmed as Shiga toxin E. coli (STEC), but as others, such as enterotoxigenic E. coli (ETEC). Pulsed field gel electrophoresis (PFGE) was used to show the diversity E. coli populations from different sources throughout the watershed. Seventy six percent of the isolates from urban sources exhibited resistance to more than one antimicrobial agent. A subsequent filtration experiment after water has gone through filtration tanks containing aquifer sand material showed that there was a 1 to 2 log reduction in E. coli in aquifer sand tank. Our data showed multiple strains of E. coli without virulence attributes, but with high distribution of resistant phenotypes. Therefore, the occurrence of E. coli with multiple resistances in the environment is a matter of great concern due to possible

  15. Microbiological Evaluation of Water Quality from Urban Watersheds for Domestic Water Supply Improvement

    Directory of Open Access Journals (Sweden)

    Alexandria K. Graves

    2011-11-01

    Full Text Available Agricultural and urban runoffs may be major sources of pollution of water bodies and major sources of bacteria affecting the quality of drinking water. Of the different pathways by which bacterial pathogens can enter drinking water, this one has received little attention to date; that is, because soils are often considered to be near perfect filters for the transport of bacterial pathogens through the subsoil to groundwater. The goals of this study were to determine the distribution, diversity, and antimicrobial resistance of pathogenic Escherichia coli isolates from low flowing river water and sediment with inputs from different sources before water is discharged into ground water and to compare microbial contamination in water and sediment at different sampling sites. Water and sediment samples were collected from 19 locations throughout the watershed for the isolation of pathogenic E. coli. Heterotrophic plate counts and E. coli were also determined after running tertiary treated water through two tanks containing aquifer sand material. Presumptive pathogenic E. coli isolates were obtained and characterized for virulent factors and antimicrobial resistance. None of the isolates was confirmed as Shiga toxin E. coli (STEC, but as others, such as enterotoxigenic E. coli (ETEC. Pulsed field gel electrophoresis (PFGE was used to show the diversity E. coli populations from different sources throughout the watershed. Seventy six percent of the isolates from urban sources exhibited resistance to more than one antimicrobial agent. A subsequent filtration experiment after water has gone through filtration tanks containing aquifer sand material showed that there was a 1 to 2 log reduction in E. coli in aquifer sand tank. Our data showed multiple strains of E. coli without virulence attributes, but with high distribution of resistant phenotypes. Therefore, the occurrence of E. coli with multiple resistances in the environment is a matter of great concern

  16. A PCSWMM/GIS-based water balance model for the Reesor Creek watershed

    Science.gov (United States)

    Smith, D.; Li, J.; Banting, D.

    2005-09-01

    This paper presents the results of a study of a watershed experiencing the pressures of land-use change resulting from urban development. The study was undertaken to facilitate an understanding of the water balance of the watershed by developing and implementing watershed procedures that are to be addressed in a watershed plan. There were three components to the research: firstly, observation of the effects of spatially distributed rainfall measurements and their effect on modelling were assessed. Secondly, the model was then calibrated by observing how differing techniques can discretize both the landscape (e.g. land-use and soil type) and incoming precipitation. Finally, a modelling methodology was developed to integrate a Geographic Information System and a hydrologic model (e.g. Storm Water Management Model) in a water balance analysis on a watershed basis. Results show that, under certain conditions, kriging spatially distributed rainfall values can help predict rainfall at ungauged (virtual) sites. Discretization of a watershed was found to affect the differences between measured and generated runoff volumes; however, this can be refined with calibration. It was seen that a strong correlation between measured and predicted rainfall values did not always guarantee a strong relationship between measured and generated runoff Recommendations include the use of a longer time series of rainfall, streamflow and predicted rainfall to observe temporal variations, and the need to assess the differences in modelled rainfall values generated by various surface interpolation methods (e.g. Inverse Distance Weighting and other kriging options) currently available in GIS packages.

  17. Rangeland health assessment - The key to understanding and assessing rangeland soil health in the Northern Great Plains

    Science.gov (United States)

    As the science related to soil and rangeland health evolves, so do their protocols and assessment methodologies. Rangeland health assessments consist of evaluating how well ecological processes such as the water cycle, energy flow and nutrient cycling are functioning at a site. Soil health is the ca...

  18. Simulated wetland conservation-restoration effects on water quantity and quality at watershed scale.

    Science.gov (United States)

    Wang, Xixi; Shang, Shiyou; Qu, Zhongyi; Liu, Tingxi; Melesse, Assefa M; Yang, Wanhong

    2010-07-01

    Wetlands are one of the most important watershed microtopographic features that affect hydrologic processes (e.g., routing) and the fate and transport of constituents (e.g., sediment and nutrients). Efforts to conserve existing wetlands and/or to restore lost wetlands require that watershed-level effects of wetlands on water quantity and water quality be quantified. Because monitoring approaches are usually cost or logistics prohibitive at watershed scale, distributed watershed models such as the Soil and Water Assessment Tool (SWAT), enhanced by the hydrologic equivalent wetland (HEW) concept developed by Wang [Wang, X., Yang, W., Melesse, A.M., 2008. Using hydrologic equivalent wetland concept within SWAT to estimate streamflow in watersheds with numerous wetlands. Trans. ASABE 51 (1), 55-72.], can be a best resort. However, there is a serious lack of information about simulated effects using this kind of integrated modeling approach. The objective of this study was to use the HEW concept in SWAT to assess effects of wetland restoration within the Broughton's Creek watershed located in southwestern Manitoba, and of wetland conservation within the upper portion of the Otter Tail River watershed located in northwestern Minnesota. The results indicated that the HEW concept allows the nonlinear functional relations between watershed processes and wetland characteristics (e.g., size and morphology) to be accurately represented in the models. The loss of the first 10-20% of the wetlands in the Minnesota study area would drastically increase the peak discharge and loadings of sediment, total phosphorus (TP), and total nitrogen (TN). On the other hand, the justifiable reductions of the peak discharge and loadings of sediment, TP, and TN in the Manitoba study area may require that 50-80% of the lost wetlands be restored. Further, the comparison between the predicted restoration and conservation effects revealed that wetland conservation seems to deserve a higher priority

  19. Hydrology and water quality in 13 watersheds in Gwinnett County, Georgia, 2001–15

    Science.gov (United States)

    Aulenbach, Brent T.; Joiner, John K.; Painter, Jaime A.

    2017-02-23

    The U.S. Geological Survey (USGS), in cooperation with Gwinnett County Department of Water Resources, established a Long-Term Trend Monitoring (LTTM) program in 1996. The LTTM program is a comprehensive, long-term, water-quantity and water-quality monitoring program designed to document and analyze the hydrologic and water-quality conditions of selected watersheds in Gwinnett County, Georgia. Water-quality monitoring initially began in six watersheds and currently [2016] includes 13 watersheds.As part of the LTTM program, streamflow, precipitation, water temperature, specific conductance, and turbidity were measured every 15 minutes for water years 2001–15 at 12 of the 13 watershed monitoring stations and for water years 2010–15 at the other watershed. In addition, discrete water-quality samples were collected seasonally from May through October (summer) and November through April (winter), including one base-flow and three stormflow event composite samples, during the study period. Samples were analyzed for nutrients (nitrogen and phosphorus), total organic carbon, trace elements (total lead and total zinc), total dissolved solids, and total suspended sediment (total suspended solids and suspended-sediment concentrations). The sampling scheme was designed to identify variations in water quality both hydrologically and seasonally.The 13 watersheds were characterized for basin slope, population density, land use for 2012, and the percentage of impervious area from 2000 to 2014. Several droughts occurred during the study period—water years 2002, 2007–08, and 2011–12. Watersheds with the highest percentage of impervious areas had the highest runoff ratios, which is the portion of precipitation that occurs as runoff. Watershed base-flow indexes, the ratio of base-flow runoff to total runoff, were inversely correlated with watershed impervious area.Flood-frequency estimates were computed for 13 streamgages in the study area that have 10 or more years of annual

  20. Conservation practice establishment in two northeast Iowa watersheds: Strategies, water quality implications, and lessons learned

    Science.gov (United States)

    Gassman, P.W.; Tisl, J.A.; Palas, E.A.; Fields, C.L.; Isenhart, T.M.; Schilling, K.E.; Wolter, C.F.; Seigley, L.S.; Helmers, M.J.

    2010-01-01

    Coldwater trout streams are important natural resources in northeast Iowa. Extensive efforts have been made by state and federal agencies to protect and improve water quality in northeast Iowa streams that include Sny Magill Creek and Bloody Run Creek, which are located in Clayton County. A series of three water quality projects were implemented in Sny Magill Creek watershed during 1988 to 1999, which were supported by multiple agencies and focused on best management practice (BMP) adoption. Water quality monitoring was performed during 1992 to 2001 to assess the impact of these installed BMPs in the Sny Magill Creek watershed using a paired watershed approach, where the Bloody Run Creek watershed served as the control. Conservation practice adoption still occurred in the Bloody Run Creek watershed during the 10-year monitoring project and accelerated after the project ended, when a multiagency supported water quality project was implemented during 2002 to 2007. Statistical analysis of the paired watershed results using a pre/post model indicated that discharge increased 8% in Sny Magill Creek watershed relative to the Bloody Run Creek watershed, turbidity declined 41%, total suspended sediment declined 7%, and NOx-N (nitrate-nitrogen plus nitrite-nitrogen) increased 15%. Similar results were obtained with a gradual change statistical model.The weak sediment reductions and increased NOx-N levels were both unexpected and indicate that dynamics between adopted BMPs and stream systems need to be better understood. Fish surveys indicate that conditions for supporting trout fisheries have improved in both streams. Important lessons to be taken from the overall study include (1) committed project coordinators, agency collaborators, and landowners/producers are all needed for successful water quality projects; (2) smaller watershed areas should be used in paired studies; (3) reductions in stream discharge may be required in these systems in order for significant sediment

  1. The public water supply protection value of forests: A watershed-scale ecosystem services based upon total organic carbon

    Science.gov (United States)

    We developed a cost-based methodology to assess the value of forested watersheds to improve water quality in public water supplies. The developed methodology is applicable to other source watersheds to determine ecosystem services for water quality. We assess the value of forest land for source wate...

  2. Daily Water Quality Forecasting System Linking Weather, Watersheds, Rivers and Dam Reservoirs Based On Numerical Simulations

    Science.gov (United States)

    Byun, C. Y.; Lee, S. J.; Oh, S. S.; Hwang, H. S.; Kim, H. S.

    2016-12-01

    Many large dam reservoirs and rivers, which are the most important water resources in Korea, are under increased pressure from various environmental issues, including an excessive growth of phytoplanktons(algae) because of eutrophication and long-term impact of turbid water on the water supply system after flood events. However most of organizations managing water quality respond to these problems after turbid water or algal blooms happen. But nowadays Korea Water Resources Corporation(K-water) has been upgrading its water quality management system to establish a predictive and preventive management paradigm not only in dam reservoirs but also in rivers and watersheds. For these, K-water has been setting up water quality forecasting systems using 3-dimensional hydrodynamic water quality model ELCOM-CAEDYM to all reservoirs, HSPF(Hydrological Simulation Program Fortran) to 4 watersheds and CE-QUAL-W2 to 4 main rivers in Korean Peninsula. For efficient operation and real time water quality modeling of 3 different models, K-water have also developed integrated software and centralized simulation hardware machines which run all models, link all in- and output together and visualizes results every day. With systems, K-water has been forecasting water quality of all reservoirs and rivers according to 5 days weather forecasting results and applying to predict the water quality changes in dams, rivers and watersheds in advance according to operation rule changes and climate changes.

  3. Uncertainty analysis for complex watershed water quality models: the parameter identifiability problem

    Science.gov (United States)

    Han, F.; Zheng, Y.

    2012-12-01

    Watershed-scale water quality simulation using distributed models like the Soil and Water Assessment Tool (SWAT) usually involves significant uncertainty. The uncertainty needs to be appropriately quantified if the simulation is used to support management practices. Many uncertainty analysis (UA) approaches have been developed for watershed hydrologic models, but their applicability to watershed water quality models, which are more complex, has not been well investigated. This study applied a Markov chain Monte Carlo (MCMC) approach, DiffeRential Evolution Adaptive Metropolis algorithm (DREAM), to the SWAT model. The sediment and total nitrogen pollution in the Newport Bay watershed (Southern California) was used as a case study. Different error assumptions were tested. The major findings include: 1) in the water quality simulation, many parameters are non-identifiable due to different causes; 2) the existence of identifiability seriously reduces the efficiency of the MCMC algorithm, and distorts the posterior distributions of the non-identifiable parameters, although the uncertainty band produced by the algorithm does not change much if enough samples are obtained. It was concluded that a sensitivity analysis (SA) followed by an identifiability analysis is necessary to reduce the non-identifiability, and enhances the applicability of a Bayesian UA approach to complex watershed water quality models. In addition, the analysis on the different causes of non-identifiablity provides insights into model tradeoffs between complexity and performance.

  4. RANGELAND SEQUESTRATION POTENTIAL ASSESSMENT

    Energy Technology Data Exchange (ETDEWEB)

    Lee Spangler; George F. Vance; Gerald E. Schuman; Justin D. Derner

    2012-03-31

    Rangelands occupy approximately half of the world's land area and store greater than 10% of the terrestrial biomass carbon and up to 30% of the global soil organic carbon. Although soil carbon sequestration rates are generally low on rangelands in comparison to croplands, increases in terrestrial carbon in rangelands resulting from management can account for significant carbon sequestration given the magnitude of this land resource. Despite the significance rangelands can play in carbon sequestration, our understanding remains limited. Researchers conducted a literature review to identify sustainably management practices that conserve existing rangeland carbon pools, as well as increase or restore carbon sequestration potentials for this type of ecosystem. The research team also reviewed the impact of grazing management on rangeland carbon dynamics, which are not well understood due to heterogeneity in grassland types. The literature review on the impact of grazing showed a wide variation of results, ranging from positive to negative to no response. On further review, the intensity of grazing appears to be a major factor in controlling rangeland soil organic carbon dynamics. In 2003, researchers conducted field sampling to assess the effect of several drought years during the period 1993-2002. Results suggested that drought can significantly impact rangeland soil organic carbon (SOC) levels, and therefore, carbon sequestration. Resampling was conducted in 2006; results again suggested that climatic conditions may have overridden management effects on SOC due to the ecological lag of the severe drought of 2002. Analysis of grazing practices during this research effort suggested that there are beneficial effects of light grazing compared to heavy grazing and non-grazing with respect to increased SOC and nitrogen contents. In general, carbon storage in rangelands also increases with increased precipitation, although researchers identified threshold levels of

  5. Genotypic Diversity of Escherichia coli in the Water and Soil of Tropical Watersheds in Hawaii ▿

    Science.gov (United States)

    Goto, Dustin K.; Yan, Tao

    2011-01-01

    High levels of Escherichia coli were frequently detected in tropical soils in Hawaii, which present important environmental sources of E. coli to water bodies. This study systematically examined E. coli isolates from water and soil of several watersheds in Hawaii and observed high overall genotypic diversity (35.5% unique genotypes). In the Manoa watershed, fewer than 9.3% of the observed E. coli genotypes in water and 6.6% in soil were shared between different sampling sites, suggesting the lack of dominant fecal sources in the watershed. High temporal variability of E. coli genotypes in soil was also observed, which suggests a dynamic E. coli population corresponding with the frequently observed high concentrations in tropical soils. When E. coli genotypes detected from the same sampling events were compared, limited sharing between the soil and water samples was observed in the majority of comparisons (73.5%). However, several comparisons reported up to 33.3% overlap of E. coli genotypes between soil and water, illustrating the potential for soil-water interactions under favorable environmental conditions. In addition, genotype accumulation curves for E. coli from water and soil indicated that the sampling efforts in the Manoa watershed could not exhaust the overall genotypic diversity. Comparisons of E. coli genotypes from other watersheds on Oahu, Hawaii, identified no apparent grouping according to sampling locations. The results of the present study demonstrate the complexity of using E. coli as a fecal indicator bacterium in tropical watersheds and highlight the need to differentiate environmental sources of E. coli from fecal sources in water quality monitoring. PMID:21515724

  6. Assessment of climate change impacts on water balance components of Heeia watershed in Hawaii

    Directory of Open Access Journals (Sweden)

    Olkeba Tolessa Leta

    2016-12-01

    New hydrological insights for the study region: Compared to continental watersheds, the Heeia watershed showed high rainfall initial abstraction due to high initial infiltration capacity of the soils. The simulated and observed streamflows generally showed a good agreement and satisfactory model performance demonstrating the applicability of SWAT for small island watersheds with large topographic, precipitation, and land-use gradients. The study also demonstrates methods to resolve data scarcity issues. Predicted climate change scenarios showed that the decrease in rainfall during wet season and marginal increase in dry season are the main factors for the overall decrease in water balance components. Specifically, the groundwater flow component may consistently decrease by as much as 15% due to predicted rainfall and temperature changes by 2100, which may have serious implications on groundwater availability in the watershed.

  7. Modeling the Monthly Water Balance of a First Order Coastal Forested Watershed

    Science.gov (United States)

    S. V. Harder; Devendra M. Amatya; T. J. Callahan; Carl C. Trettin

    2006-01-01

    A study has been conducted to evaluate a spreadsheet-based conceptual Thornthwaite monthly water balance model and the process-based DRAINMOD model for their reliability in predicting monthly water budgets of a poorly drained, first order forested watershed at the Santee Experimental Forest located along the Lower Coastal Plain of South Carolina. Measured precipitation...

  8. Experimental forest watershed studies contribution to the effect of disturbances on water quality

    Science.gov (United States)

    Daniel G. Neary

    2012-01-01

    The most sustainable and best quality fresh water sources in the world originate in forested watersheds (Dissmeyer 2000, Brooks et al. 2003, Barten and Ernst 2004). The biological, chemical, and physical characteristics of forest soils are particularly well suited to delivering high quality water to streams, and moderating the climatic extremes which affect stream...

  9. Identification of anthropogenic influences on water quality of rivers in Taihu watershed

    NARCIS (Netherlands)

    Wang, X.L.; Lu, Y.L.; Han, Jingyi; He, G.Z.; Wang, T.Y.

    2007-01-01

    Surface water bodies are progressively subjected to stress as a result of anthropogenic activities. This study assessed and examined the impact of human activities on spatial variation in the water quality of 19 rivers in the Taihu watershed. Concentrations of physicochemical parameters of surface

  10. Effects of forest harvest on stream-water quality and nitrogen cycling in the Caspar Creek watershed

    Science.gov (United States)

    Randy A. Dahlgren

    1998-01-01

    The effects of forest harvest on stream-water quality and nitrogen cycling were examined for a redwood/Douglas-fir ecosystem in the North Fork, Caspar Creek experimental watershed in northern California. Stream-water samples were collected from treated (e.g., clearcut) and reference (e.g., noncut) watersheds, and from various locations downstream from the treated...

  11. Application of large-scale, multi-resolution watershed modeling framework using the Hydrologic and Water Quality System (HAWQS)

    Science.gov (United States)

    In recent years, large-scale watershed modeling has been implemented broadly in the field of water resources planning and management. Complex hydrological, sediment, and nutrient processes can be simulated by sophisticated watershed simulation models for important issues such as water resources all...

  12. Watershed-scale evaluation of the Water Erosion Prediction Project (WEPP) model in the Lake Tahoe basin

    Science.gov (United States)

    Erin S. Brooks; Mariana Dobre; William J. Elliot; Joan Q. Wu; Jan Boll

    2016-01-01

    Forest managers need methods to evaluate the impacts of management at the watershed scale. The Water Erosion Prediction Project (WEPP) has the ability to model disturbed forested hillslopes, but has difficulty addressing some of the critical processes that are important at a watershed scale, including baseflow and water yield. In order to apply WEPP to...

  13. Spatio-temporal variation in stream water chemistry in a tropical urban watershed

    Directory of Open Access Journals (Sweden)

    Alonso Ramírez

    2014-06-01

    Full Text Available Urban activities and related infrastructure alter the natural patterns of stream physical and chemical conditions. According to the Urban Stream Syndrome, streams draining urban landscapes are characterized by high concentrations of nutrients and ions, and might have elevated water temperatures and variable oxygen concentrations. Here, we report temporal and spatial variability in stream physicochemistry in a highly urbanized watershed in Puerto Rico. The main objective of the study was to describe stream physicochemical characteristics and relate them to urban intensity, e.g., percent impervious surface cover, and watershed infrastructure, e.g., road and pipe densities. The Río Piedras Watershed in the San Juan Metropolitan Area, Puerto Rico, is one of the most urbanized regions on the island. The Río Piedras presented high solute concentrations that were related to watershed factors, such as percent impervious cover. Temporal variability in ion concentrations lacked seasonality, as did all other parameters measured except water temperature, which was lower during winter and highest during summer, as expected based on latitude. Spatially, stream physicochemistry was strongly related to watershed percent impervious cover and also to the density of urban infrastructure, e.g., roads, pipe, and building densities. Although the watershed is serviced by a sewage collection system, illegal discharges and leaky infrastructure are probably responsible for the elevated ion concentration found. Overall, the Río Piedras is an example of the response of a tropical urban watershed after major sewage inputs are removed, thus highlighting the importance of proper infrastructure maintenance and management of runoff to control ion concentrations in tropical streams.

  14. Private sector embedded water risk: Merging the corn supply chain network and regional watershed depletion

    Science.gov (United States)

    Kim, T.; Brauman, K. A.; Schmitt, J.; Goodkind, A. L.; Smith, T. M.

    2016-12-01

    Water scarcity in US corn farming regions is a significant risk consideration for the ethanol and meat production sectors, which comprise 80% of all US corn demand. Water supply risk can lead to effects across the supply chain, affecting annual corn yields. The purpose of our study is to assess the water risk to the US's most corn-intensive sectors and companies by linking watershed depletion estimates with corn production, linked to downstream companies through a corn transport model. We use a water depletion index as an improved metric for seasonal water scarcity and a corn sourcing supply chain model based on economic cost minimization. Water depletion was calculated as the fraction of renewable (ground and surface) water consumption, with estimates of more than 75% depletion on an annual average basis indicating a significant water risk. We estimated company water risk as the amount of embedded corn coming from three categories of water stressed counties. The ethanol sector had 3.1% of sourced corn grown from counties that were more than 75% depleted while the beef sector had 14.0%. From a firm perspective, Tyson, JBS, Cargill, the top three US corn demanding companies, had 4.5%, 9.6%, 12.8% of their sourced corn respectively, coming from watersheds that are more than 75% depleted. These numbers are significantly higher than the global average of 2.2% of watersheds being classified as more than 75% depleted. Our model enables corn using industries to evaluate their supply chain risk of water scarcity through modeling corn sourcing and watershed depletion, providing the private sector a new method for risk estimation. Our results suggest corn dependent industries are already linked to water scarcity risk in disproportionate amounts due to the spatial heterogeneity of corn sourcing and water scarcity.

  15. Sustainable Water and Agricultural Land Use in the Guanting Watershed under Limited Water Resources

    Science.gov (United States)

    Wechsung, F.; Möhring, J.; Otto, I. M.; Wang, X.; Guanting Project Team

    2012-04-01

    The Yongding River System is an important water source for the northeastern Chinese provinces Shanxi, Hebei, Beijing, and Tianjin. The Guanting Reservoir within this river system is one of the major water sources for Beijing, which is about 70 km away. Original planning assumed a discharge of 44 m3/s for the reservoir, but the current mean discharge rate is only about 5 m3/s; there is often hardly any discharge at all. Water scarcity is a major threat for the socio-economic development of the area. The situation is additionally aggravated by climate change impacts. Typical upstream-downstream conflicts with respect to water quantity and quality requests are mixed up with conflicts between different sectors, mainly mining, industry, and agriculture. These conflicts can be observed on different administrative levels, for example between the provinces, down to households. The German-Chinese research project "Sustainable water and agricultural land use in the Guanting Watershed under limited water resources" investigates problems and solutions related to water scarcity in the Guanting Catchment. The aim of the project is to create a vulnerability study in order to assess options for (and finally achieve) sustainable water and land use management in the Guanting region. This includes a comprehensive characterization of the current state by gap analysis and identification of pressures and impacts. The presentation gives an overview of recent project results regarding regionalization of global change scenarios and specification for water supply, evaluation of surface water quantity balances (supply-demand), evaluation of the surface water quality balances (emissions-impact thresholds), and exploration of integrative measurement planning. The first results show that climate in the area is becoming warmer and drier which leads to even more dramatically shrinking water resources. Water supply is expected to be reduced between one and two thirds. Water demand might be

  16. Environmental Systems Simulations for Carbon, Energy, Nitrogen, Water, and Watersheds: Design Principles and Pilot Testing

    Science.gov (United States)

    Lant, Christopher; Pérez-Lapeña, Blanca; Xiong, Weidong; Kraft, Steven; Kowalchuk, Rhonda; Blair, Michael

    2016-01-01

    Guided by the Next Generation Science Standards and elements of problem-based learning, four human-environment systems simulations are described in brief--carbon, energy, water, and watershed--and a fifth simulation on nitrogen is described in more depth. These science, technology, engineering, and math (STEM) education simulations illustrate…

  17. Water Quality Monitoring and Assessment in Northern New Jersey Watershed, USA

    Science.gov (United States)

    Feng, H.; Mirrer, L. K.; Pelak, N. F.; Wu, M. S.

    2012-12-01

    Over a century of rapid urbanization and industrialization in New Jersey brought visible ever-increasing stress on the resource and environmental capacities of the watershed. Environmental quality is a major concern in this region with the urbanization and economic development. As a 8-week long National Science Foundation (NSF)-supported Research Experience for Undergraduate Students (REU) program, this study compares the stream water quality in four Northern New Jersey watersheds with different land use types (i.e., urban, agricultural, and forested). A total of eight sites were chosen for this study with two sites for each watershed to investigate if the land use type has an effect on the water quality, and if so, what that effect is. Physical and chemical parameters, such as temperature, pH, conductivity, solids content, nitrate, and phosphate, were measured during this study as indicators of the water quality. A number of correlations between these parameters were found during the data analysis. Our preliminary results indicate that the land use change has a significant impact on the water quality, causing impaired rivers, streams, lakes and reservoirs in New Jersey watershed. The results from this study are important and useful for developing future environmental management strategies for environmental restoration and urban coastal development. Acknowledgement: The research was supported in part by the US National Science Foundation (Award EAR-1004829).

  18. Assessment of surface-water quantity and quality, Eagle River watershed, Colorado, 1947-2007

    Science.gov (United States)

    Williams, Cory A.; Moore, Jennifer L.; Richards, Rodney J.

    2011-01-01

    From the early mining days to the current tourism-based economy, the Eagle River watershed (ERW) in central Colorado has undergone a sequence of land-use changes that has affected the hydrology, habitat, and water quality of the area. In 2000, the USGS, in cooperation with the Colorado River Water Conservation District, Eagle County, Eagle River Water and Sanitation District, Upper Eagle Regional Water Authority, Colorado Department of Transportation, City of Aurora, Town of Eagle, Town of Gypsum, Town of Minturn, Town of Vail, Vail Resorts, City of Colorado Springs, Colorado Springs Utilities, and Denver Water, initiated a retrospective analysis of surface-water quantity and quality in the ERW.

  19. Comparison of Water Quality Trends in Two Hydrologically Similar Iowa Watersheds

    Science.gov (United States)

    Drake, C.; Arenas Amado, A.; Weber, L. J.; Thomas, N. W.

    2015-12-01

    The Iowa Water Quality Information System (IWQIS) was established in 2014 and provides access to continuously monitored water quality data at 53 locations across Iowa in near real time. The sensors measure and collect various surface water quality data, including nitrate and nitrite (NOx) concentration, specific conductance (SC), turbidity, dissolved oxygen (DO), pH, and water temperature. Using data from this network, water quality trends were compared for paired watersheds in eastern Iowa over the sensors' periods of record (April 2015 - present) by comparing upstream land use composition and anthropogenic activity (e.g. point source pollution sources). Several water quality variables, including DO, pH, and water temperature, exhibited clear diurnal and seasonal patterns and high correlation with other variables. While the watersheds share similar topography, geology, and meteorology, the amount of urban and rural land use in each differ substantially. The watershed with a greater percent of row crop agriculture (23% compared to 15%) had consistently higher NOx concentration, as expected, and greater turbidity during low flow conditions. In contrast, the watershed with more urban land use (52% compared to 11%) exhibited flashier behavior in SC and turbidity and greater levels of each over a longer duration following rain events. Additional reasons for difference in the timing and magnitude of certain water quality variables were hypothesized. These early results reveal the value of the IWQIS for monitoring the quality of Iowa's surficial waters and helping establish baseline nutrient conditions to assist with improving water quality in the state through the Iowa Nutrient Reduction Strategy.

  20. Environmental setting, water budget, and stream assessment for the Broad Run watershed, Chester County, Pennsylvania

    Science.gov (United States)

    Cinotto, Peter J.; Reif, Andrew G.; Olson, Leif E.

    2005-01-01

    The Broad Run watershed lies almost entirely in West Bradford Township, Chester County, Pa., and drains 7.08 square miles to the West Branch Brandywine Creek. Because of the potential effect of encroaching development and other stresses on the Broad Run watershed, West Bradford Township, the Chester County Water Resources Authority, and the Chester County Health Department entered into a cooperative study with the U.S. Geological Survey to complete an annual water budget and stream assessment of overall conditions. The annual water budget quantified the basic parameters of the hydrologic cycle for the climatic conditions present from April 1, 2003, to March 31, 2004. These water-budget data identified immediate needs and (or) deficits that were present within the hydrologic cycle during that period, if present; however, an annual water budget encompassing a single year does not identify long-term trends. The stream assessment was conducted in two parts and assessed the overall condition of the watershed, an overall assessment of the fluvial-geomorphic conditions within the watershed and an overall assessment of the stream-quality conditions. The data collected will document present (2004) conditions and identify potential vulnerabilities to future disturbances. For the annual period from April 1, 2003, to March 31, 2004, determination of an annual water budget indicated that of the 67.8 inches of precipitation that fell on the Broad Run watershed, 38.8 inches drained by way of streamflow to the West Branch Brandywine Creek. Of this 38.8 inches of streamflow, local-minimum hydrograph separation techniques determined that 7.30 inches originated from direct runoff and 31.5 inches originated from base flow. The remaining precipitation went into ground-water storage (1.71 inches) and was lost to evapotranspiration (27.3 inches). Ground-water recharge for this period-35.2 inches-was based on these values and an estimated ground-water evapotranspiration rate of 2 inches

  1. A Pilot Study of Watershed Flow Using Stable Water Isotopes in Support of the Development of the Lamprey River Watershed (Southeast New Hampshire) as a Hydrologic Observatory

    Science.gov (United States)

    Frades, M.; Davis, J.; Bryce, J.; McDowell, W. H.

    2008-12-01

    The Lamprey River Watershed provides a suite of ecologic, geographic, geologic, and cultural characteristics that together provide an excellent opportunity to establish a convenient, unique, instructive, and informative natural laboratory. Researchers at the University of New Hampshire are establishing the Lamprey River Watershed, located in the seacoast region of New Hampshire, as a long term hydrologic observatory, where the instrumentation, data, and results from multi-disciplinary studies can be integrated to achieve greater understanding of the hydrologic system as a whole.One component of this proposed research is the establishment of a long term record of water isotope data. The results of a 1.5-year pilot study of stable water isotopes in the Headwaters of the Lamprey River Watershed (HLRW) are the focus of this presentation. In order to better understand groundwater flowpaths and residence times within the HLRW, we used stable water isotopes as natural tracers. For the period of June 2006 through October 2007, over 200 total water samples of groundwater, surface water, precipitation, and infiltration were collected and analyzed for stable hydrogen and oxygen isotopes. Based on analysis of isotopic and hydrometric data, the groundwater system is interpreted to be comprised of three distinct but interconnected reservoirs: a shallow groundwater reservoir which does not directly contribute to stream flow at the watershed outlet and has a mean residence time greater than 9 years; a near-surface groundwater reservoir, which is fed by the shallow system, flows through surface water bodies and wetlands with a mean residence time of approximately 1.5 months, and is the primary source of baseflow in the stream network; and a deep groundwater reservoir. The findings have significant implications for the interpretation of biogeochemical mass balance models of the Lamprey River Watershed and ongoing strontium isotope and trace element tracer studies. In a broader sense

  2. A system method for the assessment of integrated water resources management (IWRM) in mountain watershed areas: the case of the "Giffre" watershed (France).

    Science.gov (United States)

    Charnay, Bérengère

    2011-07-01

    In the last fifty years, many mountain watersheds in temperate countries have known a progressive change from self-standing agro-silvo-pastoral systems to leisure dominated areas characterized by a concentration of tourist accommodations, leading to a drinking water peak during the winter tourist season, when the water level is lowest in rivers and sources. The concentration of water uses increases the pressure on "aquatic habitats" and competition between uses themselves. Consequently, a new concept was developed following the international conferences in Dublin (International Conference on Water and the Environment - ICWE) and Rio de Janeiro (UN Conference on Environment and Development), both in 1992, and was broadly acknowledged through international and European policies. It is the concept of Integrated Water Resource Management (IWRM). It meets the requirements of different uses of water and aquatic zones whilst preserving the natural functions of such areas and ensuring a satisfactory economic and social development. This paper seeks to evaluate a local water resources management system in order to implement it using IWRM in mountain watersheds. The assessment method is based on the systemic approach to take into account all components influencing a water resources management system at the watershed scale. A geographic information system was built to look into interactions between water resources, land uses, and water uses. This paper deals specifically with a spatial comparison between hydrologically sensitive areas and land uses. The method is applied to a French Alps watershed: the Giffre watershed (a tributary of the Arve in Haute-Savoie). The results emphasize both the needs and the gaps in implementing IWRM in vulnerable mountain regions.

  3. Long-term effects of nitrogen fertilizer use on ground water nitrate in two small watersheds.

    Science.gov (United States)

    Tomer, M D; Burkart, M R

    2003-01-01

    Changes in agricultural management can minimize NO3-N leaching, but then the time needed to improve ground water quality is uncertain. A study was conducted in two first-order watersheds (30 and 34 ha) in Iowa's Loess Hills. Both were managed in continuous corn (Zea mays L.) from 1964 through 1995 with similar N fertilizer applications (average 178 kg ha(-1) yr(-1)), except one received applications averaging 446 kg N ha(-1) yr(-1) between 1969 and 1974. This study determined if NO3-N from these large applications could persist in ground water and baseflow, and affect comparison between new crop rotations implemented in 1996. Piezometer nests were installed and deep cores collected in 1996, then ground water levels and NO3-N concentrations were monitored. Tritium and stable isotopes (2H, 18O) were determined on 33 water samples in 2001. Baseflow from the heavily N-fertilized watershed had larger average NO3-N concentrations, by 8 mg L(-1). Time-of-travel calculations and tritium data showed ground water resides in these watersheds for decades. "Bomb-peak" precipitation (1963-1980) most influenced tritium concentrations near lower slope positions, while deep ground water was dominantly pre-1953 precipitation. Near the stream, greater recharge and mixed-age ground water was suggested by stable isotope and tritium data, respectively. Using sediment-core data collected from the deep unsaturated zone between 1972 and 1996, the increasing depth of a NO3-N pulse was related to cumulative baseflow (r2 = 0.98), suggesting slow downward movement of NO3-N since the first experiment. Management changes implemented in 1996 will take years to fully influence ground water NO3-N. Determining ground water quality responses to new agricultural practices may take decades in some watersheds.

  4. Effect of land use change on water discharge in Srepok watershed, Central Highland, Viet Nam

    Directory of Open Access Journals (Sweden)

    Nguyen Thi Ngoc Quyen

    2014-09-01

    Full Text Available Srepok watershed plays an important role in Central Highland in Viet Nam. It impacts to developing social-economic conditions. Therefore, it is necessary to research elements which impact to natural resources in this watershed. The Soil and Water Assessment Tool (SWAT model and Geography Information System (GIS were used to simulate water discharge in the Srepok watershed. The objectives of the research were to apply GIS and SWAT model for simulation water discharge and then, we assessed land use change which impacted on water discharge in the watershed. The observed stream flow data from Ban Don Stream gauge station was used to calibrate for the period from 1981 to 2000 and then validate for the period from 2001 to 2009. After using SWAT-CUP software to calibration, NSI reached 0.63 and R square value achieved 0.64 from 2004 to 2008 in calibration and NSI gained good level at 0.74 and R square got 0.75 from 2009 to 2012 in validation step at Ban Don Station. After that, land cover in 2010 was processed like land cover in 2000 and set up SWAT model again. The simulated water discharge in scenario 1 (land use 2000 was compared with scenario 2 (land use 2010, the simulation result was not significant difference between two scenarios because the change of area of land use was not much enough to affect the fluctuation of water discharge. However, the effect of land cover on water resource could be seen clearly via total water yield. The percentage of surface flow in 2000 was twice times more than in 2010; retard and base flow in 2000 was slightly more than in 2010. Therefore, decreased surface flow, increased infiltration capacity of water and enriched base flow resulted in the growth of land cover.

  5. Industrialized watersheds have elevated risk and limited opportunities to mitigate risk through water trading

    Directory of Open Access Journals (Sweden)

    Sheila M.W. Reddy

    2015-09-01

    Full Text Available Businesses are increasingly concerned about water scarcity and its financial impacts, as well as competing needs of other stakeholders and ecosystems. Industrialized watersheds may be at more serious risk from water scarcity than previously understood because industrial and municipal users have inelastic demand and a high value for water. Previous water risk assessments have failed to sufficiently capture these economic aspects of water risk. We illustrate how hydro-economic modeling can be used to improve water risk assessments at a basin scale and we apply the methodology to the industrialized Brazos River Basin (85% municipal and industrial withdrawals and consider implications for The Dow Chemical Company׳s Freeport Operations in Texas, US. Brazos water right holders pay only operating and maintenance costs for water during normal periods; however, when shortages occur, leasing stored water or reducing production may be the only mitigation option in the short-run. Modeling of water shortages and the theoretical cost of leasing water under nine combined scenarios of demand growth and climate change suggests that water lease prices to industry could increase by 9–13X. At best, a more developed water rights and storage lease market could result in lower lease prices (2–3X; however, given that transactions would be limited it is more likely that prices would still increase by 4–13X. These results suggest that markets are unlikely to be a robust solution for the Brazos because, in contrast to other watersheds in the Western US, there is little reliable water to trade from low value users (agricultural to high value users (industry and municipalities. Looking at demand trends across the contiguous US as an indicator of water risk, 2% of watersheds have municipal and industrial demands that outstrip total surface and ground water supplies and in these watersheds industry has historically paid higher lease prices for water. This study

  6. Impacts of deforestation on water balance components of a watershed on the Brazilian East Coast

    Directory of Open Access Journals (Sweden)

    Donizete dos Reis Pereira

    2014-08-01

    Full Text Available The Brazilian East coast was intensely affected by deforestation, which drastically cut back the original biome. The possible impacts of this process on water resources are still unknown. The purpose of this study was an evaluation of the impacts of deforestation on the main water balance components of the Galo creek watershed, in the State of Espírito Santo, on the East coast of Brazil. Considering the real conditions of the watershed, the SWAT model was calibrated with data from 1997 to 2000 and validated for the period between 2001 and 2003. The calibration and validation processes were evaluated by the Nash-Sutcliffe efficiency coefficient and by the statistical parameters (determination coefficient, slope coefficient and F test of the regression model adjusted for estimated and measured flow data. After calibration and validation of the model, new simulations were carried out for three different land use scenarios: a scenario in compliance with the law (C1, assuming the preservation of PPAs (permanent preservation areas; an optimistic scenario (C2, which considers the watershed to be almost entirely covered by native vegetation; and a pessimistic scenario (C3, in which the watershed would be almost entirely covered by pasture. The scenarios C1, C2 and C3 represent a soil cover of native forest of 76, 97 and 0 %, respectively. The results were compared with the simulation, considering the real scenario (C0 with 54 % forest cover. The Nash-Sutcliffe coefficients were 0.65 and 0.70 for calibration and validation, respectively, indicating satisfactory results in the flow simulation. A mean reduction of 10 % of the native forest cover would cause a mean annual increase of approximately 11.5 mm in total runoff at the watershed outlet. Reforestation would ensure minimum flows in the dry period and regulate the maximum flow of the main watercourse of the watershed.

  7. Valuation of rangeland ecosystem services

    Science.gov (United States)

    Gascoigne, W.R.

    2011-01-01

    Economic valuation lends itself well to the anthropocentric orientation of ecosystem services. An economic perspective on ecosystems portrays them as natural assets providing a flow of goods and services valuable to individuals and society collectively. A few examples include the purification of drinking water, reduced risk from flooding and other extreme events, pollination of agricultural crops, climate regulation, and recreation opportunities from plant and animal habitat maintenance, among many others. Once these goods and services are identified and quantified, they can be monetized to complete the valuation process. The monetization of ecosystem goods and services (in the form of dollars) provides a common metric that allows for cross-comparison of attributes and evaluation of differing ecological scenarios. Complicating the monetization process is the fact that most of these goods and services are public and non-market in nature; meaning they are non-rival and non-exclusive and are typically not sold in a traditional market setting where monetary values are revealed. Instead, one must employ non-market valuation techniques, with primary valuation methods typically being very time and resource consuming, intimidating to non-economists, and often impractical. For these reasons, benefit transfer methods have gained popularity. This methodology harnesses the primary collection results of existing studies to make inferences about the economic values of non-market goods and services at an alternative policy site (in place and/or in time). For instance, if a primary valuation study on oak reestablishment on rangelands in southern California yielded a value of $30 per-acre associated with water regulation, this result can be transferred, with some adjustments, to say something about the value of an acre of oaks on rangelands in northern portions of the state. The economic valuation of rangeland ecosystem services has many roles. Economic values may be used as input

  8. Simulated water budget of a small forested watershed in the continental/maritime hydroclimatic region of the United States

    Science.gov (United States)

    Liang Wei; Timothy E. Link; Andrew T. Hudak; John D. Marshall; Kathleen L. Kavanagh; John T. Abatzoglou; Hang Zhou; Robert E. Pangle; Gerald N. Flerchinger

    2016-01-01

    Annual streamflows have decreased across mountain watersheds in the Pacific Northwest of the United States over the last ~70 years; however, in some watersheds, observed annual flows have increased. Physically based models are useful tools to reveal the combined effects of climate and vegetation on long-term water balances by explicitly simulating the internal...

  9. [Evaluating ground water vulnerability in West Lake Watershed by using DRASTIC model].

    Science.gov (United States)

    Dong, Liang; Zhu, Yinmei; Hu, Qinhai; Ogura, Norio

    2002-02-01

    Supported by Blackland GRASS Geographic Information System (GIS), the basic and special environmental databases of West Lake Watershed were established. The vulnerability map of ground water pollution was calculated and drawn by integrating GIS and DRASTIC model. Comparing to the present situation of land use, critical area of ground water pollution had been determined. The residential area accounted for 14.7% of the high susceptible area, and wastewater in the residential area should be piped and treated first.

  10. [Relationships between river water quality and land use type at watershed scale].

    Science.gov (United States)

    Yang, Sha-Sha; Tang, Cui-Wen; Liu, Li-Juan; Li, Xiao-Yu; Ye, Yin

    2013-07-01

    Based on the remote sensing images of 54 water quality monitoring stations within the Suzi River watershed, the riparian buffer zones at 6 scales were constructed by ArcGIS, and the 8 landscape indices at landscape and class levels were calculated with FRAGSTATS software. A correlation analysis on the landscape indices and river water quality was made from the viewpoints of landscape space pattern and composition. In the watershed, the landscape pattern in different riparian buffer zones had different effects on the river water quality. When the distance of the buffer zones was less than 300 m, the main landscape types were dry land, construction land, and paddy filed, and their area ratio, patch number, patch density, maximum patch index, maximum shape index, and aggregation index were higher. In these buffer zones, farmlands had higher connectedness, and thus, had greater effects on the river water quality. When the distance of the buffer zones was more than 300 m, forest land had a larger area ratio and a higher connectedness, which would benefit the improvement of river water quality to some extent. In the watershed, farmland and construction land played a key role in affecting the river water quality.

  11. Social Networks for Management of Water Scarcity: Evidence from the San Miguel Watershed, Sonora, Mexico

    Directory of Open Access Journals (Sweden)

    Luis Alan Navarro-Navarro

    2017-02-01

    Full Text Available Pervasive social and ecological water crises in Mexico remain, despite over two decades of legal and institutional backing for Integrated Water Resources Management (IWRM as a policy tenet. In this article we apply a socialshed analysis to uncover and understand the geographical and jurisdictional forces influencing the social construction and simultaneous fragmentation of the San Miguel Watershed (SMW in the state of Sonora, in Mexico’s water-scarcity bulls-eye. Specific insights derived from an empirical analysis include that water management (WM is socially embedded in dense networks of family and friends, farmers and ranchers, citizens and local government – all to varying degrees sharing information about local water crises. Irrigation water user representatives (WUR are connected across communities and within their own municipalities, but inter-watershed social links with other WUR are virtually nonexistent, despite high levels of awareness of cross-municipality WM problems. Implementation of IWRM as a federal policy by a single agency and the creation of basin councils and subsidiary technical committees for groundwater management have not been sufficient for technical – much less social – integration at the watershed level. This study shows that the SMW socialshed remains fragmented by local jurisdictions; without coordinated agency-jurisdiction-local action fomenting social connections, a socialshed will not emerge.

  12. Application of Large-Scale, Multi-Resolution Watershed Modeling Framework Using the Hydrologic and Water Quality System (HAWQS)

    OpenAIRE

    Haw Yen; Prasad Daggupati; Michael J. White; Raghavan Srinivasan; Arndt Gossel; David Wells; Jeffrey G. Arnold

    2016-01-01

    In recent years, large-scale watershed modeling has been implemented broadly in the field of water resources planning and management. Complex hydrological, sediment, and nutrient processes can be simulated by sophisticated watershed simulation models for important issues such as water resources allocation, sediment transport, and pollution control. Among commonly adopted models, the Soil and Water Assessment Tool (SWAT) has been demonstrated to provide superior performance with a large amount...

  13. Spatial Regression and Prediction of Water Quality in a Watershed with Complex Pollution Sources.

    Science.gov (United States)

    Yang, Xiaoying; Liu, Qun; Luo, Xingzhang; Zheng, Zheng

    2017-08-16

    Fast economic development, burgeoning population growth, and rapid urbanization have led to complex pollution sources contributing to water quality deterioration simultaneously in many developing countries including China. This paper explored the use of spatial regression to evaluate the impacts of watershed characteristics on ambient total nitrogen (TN) concentration in a heavily polluted watershed and make predictions across the region. Regression results have confirmed the substantial impact on TN concentration by a variety of point and non-point pollution sources. In addition, spatial regression has yielded better performance than ordinary regression in predicting TN concentrations. Due to its best performance in cross-validation, the river distance based spatial regression model was used to predict TN concentrations across the watershed. The prediction results have revealed a distinct pattern in the spatial distribution of TN concentrations and identified three critical sub-regions in priority for reducing TN loads. Our study results have indicated that spatial regression could potentially serve as an effective tool to facilitate water pollution control in watersheds under diverse physical and socio-economical conditions.

  14. Superficial Water Resource at Tempisque River Watershed, Costa Rica: Availability and Requirement Perspective

    Directory of Open Access Journals (Sweden)

    Isabel Guzmán-Arias

    2014-03-01

    Full Text Available This paper describes the status of water resources availability and demand in the upper and middle Tempisque watershed projected up to 2030 and the proposed actions to start a planning process. The resource availability scenarios incorporate the modifications inwater flows due to land use and cli­mate changes; these combined effects increases the problems of water shortages during the dry season. The resource demand scenarios include projections provided by the major users in the watershed, of which very few can envision growth expectations in terms of water consumption. The proposed resource planning process integrates the analysis conducted in this thesis and tries to identify the basic steps to be followed for the pro­per management of the resource in the future.

  15. Coupling of Water and Carbon Cycles in Boreal Ecosystems at Watershed and National Scales

    Science.gov (United States)

    Chen, J. M.; Ju, W.; Govind, A.; Sonnentag, O.

    2009-05-01

    The boreal landscapes is relatively flat giving the impression of spatial homogeneity. However, glacial activities have left distinct fingerprints on the vegetation distribution on moderately rolling terrains over the boreal landscape. Upland or lowland forests types or wetlands having various degrees of hydrological connectivitiy to the surrounding terrain are typical of the boreal landscape. The nature of the terrain creates unique hydrological conditions affecting the local-scale ecophysiological and biogeochemical processes. As part of the Canadian Carbon Program, we investigated the importance of lateral water redistribution through surface and subsurface flows in the spatial distribution of the vertical fluxes of water and carbon. A spatially explicit hydroecological model (BEPS-TerrainLab) has been developed and tested in forested and wetland watersheds . Remotely sensed vegetation parameters along with other spatial datasets are used to run this model, and tower flux data are used for partial validation. It is demonstrated in both forest and wetland watersheds that ignoring the lateral water redistribution over the landscape, commonly done in 1-dimensional bucket models, can cause considerable biases in the vertical carbon and water flux estimation, in addition to the distortion of the spatial patterns of these fluxes. The biases in the carbon flux are considerably larger than those in the water flux. The significance of these findings in national carbon budget estimation is demonstrated by separate modeling of 2015 watersheds over the Canadian landmass.

  16. STABLE ISOTOPES AS INDICATORS OF SOIL WATER DYNAMICS IN WATERSHEDS

    Science.gov (United States)

    Stream water quality and quantity depend on discharge rates of water and nutrients from soils. However, soil-water storage is very dynamic and strongly influenced by plants. We analyzed stable isotopes of oxygen and hydrogen to quantify spatial and temporal changes in evaporati...

  17. Future scenarios of impacts to ecosystem services on California rangelands

    Science.gov (United States)

    Byrd, Kristin; Alvarez, Pelayo; Flint, Lorraine; Flint, Alan

    2014-01-01

    The 18 million acres of rangelands in the Central Valley of California provide multiple benefits or “ecosystem services” to people—including wildlife habitat, water supply, open space, recreation, and cultural resources. Most of this land is privately owned and managed for livestock production. These rangelands are vulnerable to land-use conversion and climate change. To help resource managers assess the impacts of land-use change and climate change, U.S. Geological Survey scientists and their cooperators developed scenarios to quantify and map changes to three main rangeland ecosystem services—wildlife habitat, water supply, and carbon sequestration. Project results will help prioritize strategies to conserve these rangelands and the ecosystem services that they provide.

  18. Quantification of BMPs Selection and Spatial Placement Impact on Water Quality Controlling Plans in Lower Bear River Watershed, Utah

    Science.gov (United States)

    Salha, A. A.; Stevens, D. K.

    2016-12-01

    The aim of the watershed-management program in Box Elder County, Utah set by Utah Division of Water Quality (UDEQ) is to evaluate the effectiveness and spatial placement of the implemented best-management practices (BMP) for controlling nonpoint-source contamination at watershed scale. The need to evaluate the performance of BMPs would help future policy and program decisions making as desired end results. The environmental and costs benefits of BMPs in Lower Bear River watershed have seldom been measured beyond field experiments. Yet, implemented practices have rarely been evaluated at the watershed scale where the combined effects of variable soils, climatic conditions, topography and land use/covers and management conditions may significantly change anticipated results and reductions loads. Such evaluation requires distributed watershed models that are necessary for quantifying and reproducing the movement of water, sediments and nutrients. Soil and Water Assessment Tool (SWAT) model is selected as a watershed level tool to identify contaminant nonpoint sources (critical zones) and areas of high pollution risks. Water quality concerns have been documented and are primarily attributed to high phosphorus and total suspended sediment concentrations caused by agricultural and farming practices (required load is 460 kg/day of total phosphorus based on 0.075 mg/l and an average of total suspended solids of 90 mg/l). Input data such as digital elevation model (DEM), land use/Land cover (LULC), soils, and climate data for 10 years (2000-2010) is utilized along with observed water quality at the watershed outlet (USGS) and some discrete monitoring points within the watershed. Statistical and spatial analysis of scenarios of management practices (BMP's) are not implemented (before implementation), during implementation, and after BMP's have been studied to determine whether water quality of the two main water bodies has improved as required by the LBMR watershed's TMDL

  19. Drought and rangelands.

    Science.gov (United States)

    Droughts are common and occur regularly in Oklahoma. They’re the most costly natural hazard to the United States, and estimates show a $6-$8 billion annual loss to the nation’s farmers and rancher. With the current drought impacting Oklahoma, people managing rangelands are concerned with the short...

  20. The relationship between the Municipal Master Plan and local Watershed Plans in water management

    Directory of Open Access Journals (Sweden)

    Denise Gallo Pizella

    2015-07-01

    Full Text Available The National Water Resources Policy has as one of its tools the drafting of local Water Resource Plans. In view of water resources planning and its relationship to land use planning, the aim of this work is to analyze the institutional and legal difficulties and the potential for an integrated system of water resources management. For this, we used the method of documentary and bibliographic research, beginning with the “Estatuto da Cidade”, a law for urban policy in Brazil, and literature on water management at the municipal and watershed levels. At the municipal level, the “Master Plan” (municipal plan of land use planning became the main instrument of territorial and municipal management, defining the parameters for the compliance of social, environmental and economic functions of real property. In this sense, the municipalities have a responsibility to protect water resources and, without local support, territorial and water management cannot be integrated in the context of the river basin. Despite the difficulties of including environmental variable in urban planning, the Master Plan has the potential to shape local water management systems that are environmentally sustainable and that progressively improve water quality and quantity within the watershed. Similarly, with more significant participation of the municipality in the Basin Committee, it is possible that the forms of municipal land use and occupation can be considered during the development and implementation of the Basin Plan. Thus, the management of water resources can occur integrally.

  1. Landscape and plant physiological controls on water dynamics within a watershed

    Science.gov (United States)

    Hu, J.; Looker, N. T.; Martin, J. T.; Hoylman, Z. H.; Jencso, K. G.

    2014-12-01

    Across the Western U.S., declining snowpacks have resulted in increased water limitation, leading to reduced productivity in high elevation forests. While our current understanding of how forests respond to climate change is typically focused on measuring/modeling the physiological responses and climate feedbacks, our study aims to combine physiology with hydrology to examine how landscape topography modulates the sensitivity of forests to climate. In a forested watershed in Western Montana, we linked climate variability to the physical watershed characteristics and the physiological response of vegetation to examine forest transpiration and productivity rates. Across the entire watershed, we found a strong relationship between productivity and the topographic wetness index, a proxy for soil moisture storage. However, this relationship was highly dependent on the intensity of solar radiation, suggesting that at high elevations productivity was limited by temperature, while at low elevations productivity was limited by moisture. In order to identify the mechanisms responsible for this relationship, we then examined how different coniferous species respond to changing environmental and hydrologic regimes. We first examined transpiration and productivity rates at the hillslope scale at four plots, ranging in elevation and aspect across the watershed. We found trees growing in the hollows had higher transpiration and productivity rates than trees growing in the side slope, but that these differences were more pronounced at lower elevations. We then used oxygen isotope to examine water source use by different species across the watershed. We found that trees growing in the hollows used snowmelt for a longer period. This was most likely due to upslope subsidies of snowmelt water to the hollow areas. However, we found that trees growing at lower elevations used proportionally more snowmelt than trees at the higher elevations. This was most likely due to the trees at lower

  2. Landscape and plant physiological controls on water dynamics and forest productivity within a watershed

    Science.gov (United States)

    Hu, Jia; Jencso, Kelsey; Looker, Nathaniel; Martin, Justin; Hoylman, Zachary

    2015-04-01

    Across the Western U.S., declining snowpacks have resulted in increased water limitation, leading to reduced productivity in high elevation forests. While our current understanding of how forests respond to climate change is typically focused on measuring/modeling the physiological responses and climate feedbacks, our study aims to combine physiology with hydrology to examine how landscape topography modulates the sensitivity of forests to climate. In a forested watershed in Western Montana, we linked climate variability to the physical watershed characteristics and the physiological response of vegetation to examine forest transpiration and productivity rates. Across the entire watershed, we found a strong relationship between productivity and the topographic wetness index, a proxy for soil moisture storage. However, this relationship was highly dependent on the intensity of solar radiation, suggesting that at high elevations productivity was limited by temperature, while at low elevations productivity was limited by moisture. In order to identify the mechanisms responsible for this relationship, we then examined how different coniferous species respond to changing environmental and hydrologic regimes. We first examined transpiration and productivity rates at the hillslope scale at four plots, ranging in elevation and aspect across the watershed. We found trees growing in the hollows had higher transpiration and productivity rates than trees growing in the side slope, but that these differences were more pronounced at lower elevations. We then used oxygen isotope to examine water source use by different species across the watershed. We found that trees growing in the hollows used snowmelt for a longer period. This was most likely due to upslope subsidies of snowmelt water to the hollow areas. However, we found that trees growing at lower elevations used proportionally more snowmelt than trees at the higher elevations. This was most likely due to the trees at lower

  3. Water quality assessment and meta model development in Melen watershed - Turkey.

    Science.gov (United States)

    Erturk, Ali; Gurel, Melike; Ekdal, Alpaslan; Tavsan, Cigdem; Ugurluoglu, Aysegul; Seker, Dursun Zafer; Tanik, Aysegul; Ozturk, Izzet

    2010-07-01

    Istanbul, being one of the highly populated metropolitan areas of the world, has been facing water scarcity since the past decade. Water transfer from Melen Watershed was considered as the most feasible option to supply water to Istanbul due to its high water potential and relatively less degraded water quality. This study consists of two parts. In the first part, water quality data covering 26 parameters from 5 monitoring stations were analyzed and assessed due to the requirements of the "Quality Required of Surface Water Intended for the Abstraction of Drinking Water" regulation. In the second part, a one-dimensional stream water quality model with simple water quality kinetics was developed. It formed a basic design for more advanced water quality models for the watershed. The reason for assessing the water quality data and developing a model was to provide information for decision making on preliminary actions to prevent any further deterioration of existing water quality. According to the water quality assessment at the water abstraction point, Melen River has relatively poor water quality with regard to NH(4)(+), BOD(5), faecal streptococcus, manganese and phenol parameters, and is unsuitable for drinking water abstraction in terms of COD, PO(4)(3-), total coliform, total suspended solids, mercury and total chromium parameters. The results derived from the model were found to be consistent with the water quality assessment. It also showed that relatively high inorganic nitrogen and phosphorus concentrations along the streams are related to diffuse nutrient loads that should be managed together with municipal and industrial wastewaters. Copyright 2010 Elsevier Ltd. All rights reserved.

  4. An integrated system dynamics model developed for managing lake water quality at the watershed scale.

    Science.gov (United States)

    Liu, Hui; Benoit, Gaboury; Liu, Tao; Liu, Yong; Guo, Huaicheng

    2015-05-15

    A reliable system simulation to relate socioeconomic development with water environment and to comprehensively represent a watershed's dynamic features is important. In this study, after identifying lake watershed system processes, we developed a system dynamics modeling framework for managing lake water quality at the watershed scale. Two reinforcing loops (Development and Investment Promotion) and three balancing loops (Pollution, Resource Consumption, and Pollution Control) were constituted. Based on this work, we constructed Stock and Flow Diagrams that embedded a pollutant load model and a lake water quality model into a socioeconomic system dynamics model. The Dianchi Lake in Yunnan Province, China, which is the sixth largest and among the most severely polluted freshwater lakes in China, was employed as a case study to demonstrate the applicability of the model. Water quality parameters considered in the model included chemical oxygen demand (COD), total nitrogen (TN), and total phosphorus (TP). The business-as-usual (BAU) scenario and three alternative management scenarios on spatial adjustment of industries and population (S1), wastewater treatment capacity construction (S2), and structural adjustment of agriculture (S3), were simulated to assess the effectiveness of certain policies in improving water quality. Results showed that S2 is most effective scenario, and the COD, TN, and TP concentrations in Caohai in 2030 are 52.5, 10.9, and 0.8 mg/L, while those in Waihai are 9.6, 1.2, and 0.08 mg/L, with sustained development in the watershed. Thus, the model can help support the decision making required in development and environmental protection strategies. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Managing Watersheds with WMOST

    Science.gov (United States)

    The Watershed Management Optimization Support Tool (WMOST) allows water-resource managers and planners to screen a wide range of practices for cost-effectiveness in achieving watershed or water utilities management goals.

  6. Land use cover changes and water quality of Cipunten Agung Watershed Banten

    Science.gov (United States)

    Karima, Afifa; Leonardus Kaswanto, Regan

    2017-01-01

    In general, the land and natural resources utilization of Cipunteng Agung Watershed could be classified into protected and cultivated region. Based on satellite imagery classification, protected region covers 885.76 ha (22.71%), while cultivated region occupied 3,041.69 ha (77.29%) in 2011. It means that the land use and covers change (LUCC) to be cultivated rapidly increase. Those conditions had impacted positively to the local economy development, however it had negatively degrades water quality in Ciputen Agung river. Therefore, the purpose of this research is to analyze LUCC impacts to the water quality (WQ) in Cipunten Agung watershed. Supervised classification method and Water Pollution Index (WPI) approach were correlated to define the optimal solution to reduce the rate of LUCC. The result shows that area of cultivation tree and paddy field are higher than others in midstream, and settlement is higher in downstream, particularly at riparian landscapes. The concentration of total phospate, nitrite, and nitrate which indicated from agriculture land were complies with WPI class 2 until 4 standart. The rate of LUCC of Cipunten Agung watershed and the density of settlement are potential to be the driving factor of water quality degradation. Regional planning with ecology approach was recommended for sustainable development of Cipunten Agung Wateshed.

  7. Empirical Modeling of Stream Water Quality for Complex Coastal-Urban Watersheds

    Science.gov (United States)

    Al-Amin, S.; Abdul-Aziz, O.

    2013-12-01

    This study develops an understanding of the relative influence of land uses, surface hydrology, groundwater, seawater, and upstream contributions on the in-stream water quality of six highly urbanized, complex urban watersheds of South Florida by analyzing seasonal (Winter, Spring, Summer, and Fall) time-series of field data. We first explored the correlations among quality parameters (i.e., total nitrogen, total phosphorus, dissolved oxygen and specific conductance) and their changes with distance and time. Principle component analysis was then conducted to investigate the mutual correlations and potential group formations among the predictor and response variables. The findings were leveraged to develop regression-based non-linear empirical models for explaining stream water quality in relation to internal (land uses and hydrology) and external (upstream contribution, seawater) sources and drivers. In-stream dissolved oxygen and total phosphorus in the watersheds were dictated by internal stressors, while external stressors were dominant for total nitrogen and specific conductance. The research findings provide important insights into the dominant stressors of seasonal stream water quality of complex coastal-urban watersheds under a changing environment. The research tools will be useful for developing proactive monitoring and seasonally exclusive management strategies for urban stream water quality improvement in South Florida and around the world.

  8. Managing the livestock– Wildlife interface on rangelands

    Science.gov (United States)

    du Toit, Johan T.; Cross, Paul C.; Valeix, Marion

    2017-01-01

    On rangelands the livestock–wildlife interface is mostly characterized by management actions aimed at controlling problems associated with competition, disease, and depredation. Wildlife communities (especially the large vertebrate species) are typically incompatible with agricultural development because the opportunity costs of wildlife conservation are unaffordable except in arid and semi-arid regions. Ecological factors including the provision of supplementary food and water for livestock, together with the persecution of large predators, result in livestock replacing wildlife at biomass densities far exceeding those of indigenous ungulates. Diseases are difficult to eradicate from free-ranging wildlife populations and so veterinary controls usually focus on separating commercial livestock herds from wildlife. Persecution of large carnivores due to their depredation of livestock has caused the virtual eradication of apex predators from most rangelands. However, recent research points to a broad range of solutions to reduce conflict at the livestock–wildlife interface. Conserving wildlife bolsters the adaptive capacity of a rangeland by providing stakeholders with options for dealing with environmental change. This is contingent upon local communities being empowered to benefit directly from their wildlife resources within a management framework that integrates land-use sectors at the landscape scale. As rangelands undergo irreversible changes caused by species invasions and climate forcings, the future perspective favors a proactive shift in attitude towards the livestock–wildlife interface, from problem control to asset management.

  9. Hydrogeology and Ground-Water Flow in the Opequon Creek Watershed area, Virginia and West Virginia

    Science.gov (United States)

    Kozar, Mark D.; Weary, David J.

    2009-01-01

    Due to increasing population and economic development in the northern Shenandoah Valley of Virginia and West Virginia, water availability has become a primary concern for water-resource managers in the region. To address these issues, the U.S. Geological Survey (USGS), in cooperation with the West Virginia Department of Health and Human Services and the West Virginia Department of Environmental Protection, developed a numerical steady-state simulation of ground-water flow for the 1,013-square-kilometer Opequon Creek watershed area. The model was based on data aggregated for several recently completed and ongoing USGS hydrogeologic investigations conducted in Jefferson, Berkeley, and Morgan Counties in West Virginia and Clarke, Frederick, and Warren Counties in Virginia. A previous detailed hydrogeologic assessment of the watershed area of Hopewell Run (tributary to the Opequon Creek), which includes the USGS Leetown Science Center in Jefferson County, West Virginia, provided key understanding of ground-water flow processes in the aquifer. The ground-water flow model developed for the Opequon Creek watershed area is a steady-state, three-layer representation of ground-water flow in the region. The primary objective of the simulation was to develop water budgets for average and drought hydrologic conditions. The simulation results can provide water managers with preliminary estimates on which water-resource decisions may be based. Results of the ground-water flow simulation of the Opequon Creek watershed area indicate that hydrogeologic concepts developed for the Hopewell Run watershed area can be extrapolated to the larger watershed model. Sensitivity analyses conducted as part of the current modeling effort and geographic information system analyses of spring location and yield reveal that thrust and cross-strike faults and low-permeability bedding, which provide structural and lithologic controls, respectively, on ground-water flow, must be incorporated into the

  10. Using geostatistical methods to estimate snow water equivalence distribution in a mountain watershed

    Science.gov (United States)

    Balk, B.; Elder, K.; Baron, Jill S.

    1998-01-01

    Knowledge of the spatial distribution of snow water equivalence (SWE) is necessary to adequately forecast the volume and timing of snowmelt runoff.  In April 1997, peak accumulation snow depth and density measurements were independently taken in the Loch Vale watershed (6.6 km2), Rocky Mountain National Park, Colorado.  Geostatistics and classical statistics were used to estimate SWE distribution across the watershed.  Snow depths were spatially distributed across the watershed through kriging interpolation methods which provide unbiased estimates that have minimum variances.  Snow densities were spatially modeled through regression analysis.  Combining the modeled depth and density with snow-covered area (SCA produced an estimate of the spatial distribution of SWE.  The kriged estimates of snow depth explained 37-68% of the observed variance in the measured depths.  Steep slopes, variably strong winds, and complex energy balance in the watershed contribute to a large degree of heterogeneity in snow depth.

  11. Land use change impacts on water quality in three lake winnipeg watersheds.

    Science.gov (United States)

    Yang, Qi; Leon, Luis F; Booty, William G; Wong, Isaac W; McCrimmon, Craig; Fong, Phil; Michiels, Patsy; Vanrobaeys, Jason; Benoy, Glenn

    2014-09-01

    Lake Winnipeg eutrophication results from excess nutrient loading due to agricultural activities across the watershed. Estimating nonpoint-source pollution and the mitigation effects of beneficial management practices (BMPs) is an important step in protecting the water quality of streams and receiving waters. The use of computer models to systematically compare different landscapes and agricultural systems across the Red-Assiniboine basin has not been attempted at watersheds of this size in Manitoba. In this study, the Soil and Water Assessment Tool was applied and calibrated for three pilot watersheds of the Lake Winnipeg basin. Monthly flow calibration yielded overall satisfactory Nash-Sutcliffe efficiency (NSE), with values above 0.7 for all simulations. Total phosphorus (TP) calibration NSE ranged from 0.64 to 0.76, total N (TN) ranged from 0.22 to 0.75, and total suspended solids (TSS) ranged from 0.29 to 0.68. Based on the assessment of the TP exceedance levels from 1993 to 2007, annual loads were above proposed objectives for the three watersheds more than half of the time. Four BMP scenarios based on land use changes were studied in the watersheds: annual cropland to hay land (ACHL), wetland restoration (WR), marginal annual cropland conversion to hay land (MACHL), and wetland restoration on marginal cropland (WRMAC). Of these land use change scenarios, ACHL had the greatest impact: TSS loads were reduced by 33 to 65%, TN by 58 to 82%, and TP by 38 to 72% over the simulation period. By analyzing unit area and percentage of load reduction, the results indicate that the WR and WRMAC scenarios had a significant impact on water quality in high loading zones in the three watersheds. Such reductions of sediment, N, and P are possible through land use change scenarios, suggesting that land conservation should be a key component of any Lake Winnipeg restoration strategy. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil

  12. Soil and Water Assessment Tool model predictions of annual maximum pesticide concentrations in high vulnerability watersheds.

    Science.gov (United States)

    Winchell, Michael F; Peranginangin, Natalia; Srinivasan, Raghavan; Chen, Wenlin

    2017-11-29

    Recent national regulatory assessments of potential pesticide exposure of threatened and endangered species in aquatic habitats have led to increased need for watershed-scale predictions of pesticide concentrations in flowing water bodies. This study was conducted to assess the ability of the uncalibrated Soil and Water Assessment Tool (SWAT) to predict annual maximum pesticide concentrations in the flowing water bodies of highly vulnerable small- to medium-sized watersheds. The SWAT was applied to 27 watersheds, largely within the midwest corn belt of the United States, ranging from 20 to 386 km2 , and evaluated using consistent input data sets and an uncalibrated parameterization approach. The watersheds were selected from the Atrazine Ecological Exposure Monitoring Program and the Heidelberg Tributary Loading Program, both of which contain high temporal resolution atrazine sampling data from watersheds with exceptionally high vulnerability to atrazine exposure. The model performance was assessed based upon predictions of annual maximum atrazine concentrations in 1-d and 60-d durations, predictions critical in pesticide-threatened and endangered species risk assessments when evaluating potential acute and chronic exposure to aquatic organisms. The simulation results showed that for nearly half of the watersheds simulated, the uncalibrated SWAT model was able to predict annual maximum pesticide concentrations within a narrow range of uncertainty resulting from atrazine application timing patterns. An uncalibrated model's predictive performance is essential for the assessment of pesticide exposure in flowing water bodies, the majority of which have insufficient monitoring data for direct calibration, even in data-rich countries. In situations in which SWAT over- or underpredicted the annual maximum concentrations, the magnitude of the over- or underprediction was commonly less than a factor of 2, indicating that the model and uncalibrated parameterization

  13. Hydromentor: An integrated water resources monitoring and management system at modified semi-arid watersheds

    Science.gov (United States)

    Vasiliades, Lampros; Sidiropoulos, Pantelis; Tzabiras, John; Kokkinos, Konstantinos; Spiliotopoulos, Marios; Papaioannou, George; Fafoutis, Chrysostomos; Michailidou, Kalliopi; Tziatzios, George; Loukas, Athanasios; Mylopoulos, Nikitas

    2015-04-01

    Natural and engineered water systems interact throughout watersheds and while there is clearly a link between watershed activities and the quantity and quality of water entering the engineered environment, these systems are considered distinct operational systems. As a result, the strategic approach to data management and modeling within the two systems is very different, leading to significant difficulties in integrating the two systems in order to make comprehensive watershed decisions. In this paper, we describe the "HYDROMENTOR" research project, a highly-structured data storage and exchange system that integrates multiple tools and models describing both natural and modified environments, to provide an integrated tool for management of water resources. Our underlying objective in presenting our conceptual design for this water information system is to develop an integrated and automated system that will achieve monitoring and management of the water quantity and quality at watershed level for both surface water (rivers and lakes) and ground water resources (aquifers). The uniqueness of the system is the integrated treatment of the water resources management issue in terms of water quantity and quality in current climate conditions and in future conditions of climatic change. On an operational level, the system provides automated warnings when the availability, use and pollution levels exceed allowable limits pre-set by the management authorities. Decision making with respect to the apportionment of water use by surface and ground water resources are aided through this system, while the relationship between the polluting activity of a source to total incoming pollution by sources are determined; this way, the best management practices for dealing with a crisis are proposed. The computational system allows the development and application of actions, interventions and policies (alternative management scenarios) so that the impacts of climate change in quantity

  14. Estimating watershed degradation over the last century and its impact on water-treatment costs for the world's large cities.

    Science.gov (United States)

    McDonald, Robert I; Weber, Katherine F; Padowski, Julie; Boucher, Tim; Shemie, Daniel

    2016-08-09

    Urban water systems are impacted by land use within their source watersheds, as it affects raw water quality and thus the costs of water treatment. However, global estimates of the effect of land cover change on urban water-treatment costs have been hampered by a lack of global information on urban source watersheds. Here, we use a unique map of the urban source watersheds for 309 large cities (population > 750,000), combined with long-term data on anthropogenic land-use change in their source watersheds and data on water-treatment costs. We show that anthropogenic activity is highly correlated with sediment and nutrient pollution levels, which is in turn highly correlated with treatment costs. Over our study period (1900-2005), median population density has increased by a factor of 5.4 in urban source watersheds, whereas ranching and cropland use have increased by a factor of 3.4 and 2.0, respectively. Nearly all (90%) of urban source watersheds have had some level of watershed degradation, with the average pollutant yield of urban source watersheds increasing by 40% for sediment, 47% for phosphorus, and 119% for nitrogen. We estimate the degradation of watersheds over our study period has impacted treatment costs for 29% of cities globally, with operation and maintenance costs for impacted cities increasing on average by 53 ± 5% and replacement capital costs increasing by 44 ± 14%. We discuss why this widespread degradation might be occurring, and strategies cities have used to slow natural land cover loss.

  15. Groundwater/surface-water interactions in the Bad River Watershed, Wisconsin

    Science.gov (United States)

    Leaf, Andrew T.; Fienen, Michael N.; Hunt, Randall J.; Buchwald, Cheryl A.

    2015-11-23

    A groundwater-flow model was developed for the Bad River Watershed and surrounding area by using the U.S. Geological Survey (USGS) finite-difference code MODFLOW-NWT. The model simulates steady-state groundwater-flow and base flow in streams by using the streamflow routing (SFR) package. The objectives of this study were to: (1) develop an improved understanding of the groundwater-flow system in the Bad River Watershed at the regional scale, including the sources of water to the Bad River Band of Lake Superior Chippewa Reservation (Reservation) and groundwater/surface-water interactions; (2) provide a quantitative platform for evaluating future impacts to the watershed, which can be used as a starting point for more detailed investigations at the local scale; and (3) identify areas where more data are needed. This report describes the construction and calibration of the groundwater-flow model that was subsequently used for analyzing potential locations for the collection of additional field data, including new observations of water-table elevation for refining the conceptualization and corresponding numerical model of the hydrogeologic system.

  16. Rainfall, streamflow, and water-quality data for five small watersheds, Nashville, Tennessee, 1990-92

    Science.gov (United States)

    Outlaw, George S.; Hoos, Anne B.; Pankey, John T.

    1994-01-01

    Rainfall, streamflow, and water-quality data were collected furing storm conditions at five urban watersheds in Nashville, Tennessee. These data can be used to build a database for developing predictive models of the relations between storm- water quality and land use, storm characteristics, and seasonal variations. The primary land and mix of land uses was different for each watershed. Stormwater samples were collected during three storms at each watershed and analyzed for selected volatile, acidic and base/neutral organic compounds; organic pesticides; trace metals; conventional pollutants; and several physical properties. Storm loads were computed for all constituents and properties with event mean concentration above the minimum reporting level. None of the samples con- tained acidic organic compounds at concentrations above the minimum reporting levels. Several constituents in each of the other categories, however, were present at concentrations above the minimum reporting level. For 21 of these constituents, water-quality criteria have been pro- mulgated by the State of Tennessee. For only 8 of the 21 did the value exceed the most restrictive of the criteria: pyrene, dieldrin, and mercury concen- trations and counts of fecal coliform exceeded the criteria for recreational use, copper and zinc concentrations and pH value exceeded the criteria for fish and aquatic life, and lead concentrations exceeded the criteria for domestic supply.

  17. Climate-change-driven deterioration of water quality in a mineralized watershed

    Science.gov (United States)

    Todd, Andrew; Manning, Andrew H.; Verplanck, Philip L.; Crouch, Caitlin; McKnight, Diane M.; Dunham, Ryan

    2012-01-01

    A unique 30-year streamwater chemistry data set from a mineralized alpine watershed with naturally acidic, metal-rich water displays dissolved concentrations of Zn and other metals of ecological concern increasing by 100–400% (400–2000 μg/L) during low-flow months, when metal concentrations are highest. SO4 and other major ions show similar increases. A lack of natural or anthropogenic land disturbances in the watershed during the study period suggests that climate change is the underlying cause. Local mean annual and mean summer air temperatures have increased at a rate of 0.2–1.2 °C/decade since the 1980s. Other climatic and hydrologic indices, including stream discharge during low-flow months, do not display statistically significant trends. Consideration of potential specific causal mechanisms driven by rising temperatures suggests that melting of permafrost and falling water tables (from decreased recharge) are probable explanations for the increasing concentrations. The prospect of future widespread increases in dissolved solutes from mineralized watersheds is concerning given likely negative impacts on downstream ecosystems and water resources, and complications created for the establishment of attainable remediation objectives at mine sites.

  18. Climate-change-driven deterioration of water quality in a mineralized watershed.

    Science.gov (United States)

    Todd, Andrew S; Manning, Andrew H; Verplanck, Philip L; Crouch, Caitlin; McKnight, Diane M; Dunham, Ryan

    2012-09-04

    A unique 30-year streamwater chemistry data set from a mineralized alpine watershed with naturally acidic, metal-rich water displays dissolved concentrations of Zn and other metals of ecological concern increasing by 100-400% (400-2000 μg/L) during low-flow months, when metal concentrations are highest. SO(4) and other major ions show similar increases. A lack of natural or anthropogenic land disturbances in the watershed during the study period suggests that climate change is the underlying cause. Local mean annual and mean summer air temperatures have increased at a rate of 0.2-1.2 °C/decade since the 1980s. Other climatic and hydrologic indices, including stream discharge during low-flow months, do not display statistically significant trends. Consideration of potential specific causal mechanisms driven by rising temperatures suggests that melting of permafrost and falling water tables (from decreased recharge) are probable explanations for the increasing concentrations. The prospect of future widespread increases in dissolved solutes from mineralized watersheds is concerning given likely negative impacts on downstream ecosystems and water resources, and complications created for the establishment of attainable remediation objectives at mine sites.

  19. Conewago Stream Teams - including youth in watershed restoration creates local watershed connections, prompts community service, and increases water literacy in youth

    Science.gov (United States)

    Jennifer Fetter; Sanford Smith; Matt Royer

    2016-01-01

    Youth in Pennsylvania’s Dauphin, Lebanon, and Lancaster Counties were invited to be part of a unique opportunity: a chance to learn, hands-on, about the water in their own community and how their daily lives impact that water. This is the mission of the 4-H Stream Teams program, which was piloted within the Conewago Creek Watershed and surrounding communities in 2010-...

  20. Simulation of the water balance of boreal watersheds of northeastern British Columbia, Canada using MIKE SHE, an integrated hydrological model

    Science.gov (United States)

    Abadzadesahraei, S.; Déry, S.; Rex, J. F.

    2016-12-01

    Northeastern British Columbia (BC) is undergoing rapid development for oil and gas extraction, largely depending on subsurface hydraulic fracturing (fracking), which relies on available freshwater. Even though this industrial activity has made substantial contributions to regional and provincial economies, it is important to ensure that sufficient and sustainable water supplies are available for all those dependent on the resource, including ecological systems. Further, BC statistics predict that the northeastern region's population will increase by 30% over the next 25 years, thereby amplifying the demands of domestic and industrial water usage. Hence, given the increasing demands for surface water in the complex wetlands of northeastern BC, obtaining accurate long-term water balance information is of vital importance. Thus, this study aims to simulate the 1979-2014 water balance at two boreal watersheds using the MIKE SHE model. More specifically, this research intends to quantify the historical, and regional, water budgets and their associated hydrological processes at two boreal watersheds—the Coles Lake and Tsea Lake watersheds—in northeastern BC. The development of coupled groundwater and surface water model of these watersheds are discussed. The model setup, calibration process, and results are presented, focusing on the water balance of boreal watersheds. Hydrological components within these watersheds are quantified through a combination of intensive fieldwork, observational data, analysis and numerical modeling. The output from the model provides important information for decision makers to manage water resources in northeastern BC. Keywords: Northeastern BC; boreal watershed; water balance; MIKE SHE hydrological model.

  1. Remote sensing as a tool for watershed-wide estimation of net solar radiation and water loss to the atmosphere

    Science.gov (United States)

    Khorram, S.; Thomas, R. W.

    1976-01-01

    Results are presented for a study intended to develop a general remote sensing-aided cost-effective procedure to estimate watershed-wide water loss to the atmosphere via evapotranspiration and to estimate net solar radiation over the watershed. Evapotranspiration estimation employs a basic two-stage two-phase sample of three information resolution levels. Net solar radiation is taken as one of the variables at each level of evapotranspiration modeling. The input information for models requiring spatial information will be provided by Landsat digital data, environmental satellite data, ground meteorological data, ground sample unit information, and topographic data. The outputs of the sampling-estimation/data bank system will be in-place maps of evapotranspiration on a data resolution element basis, watershed-wide evapotranspiration isopleths, and estimates of watershed and subbasin total evapotranspiration with associated statistical confidence bounds. The methodology developed is being tested primarily on the Spanish Creek Watershed Plumas County, California.

  2. Dynamics of Potamopyrgus antipodarum infestations and seasonal water temperatures in a heavily used recreational watershed in intermountain North America

    Science.gov (United States)

    Moffitt, Christine M.; James, Christopher A.

    2012-01-01

    Following the discovery of New Zealand mudsnails, Potamopyrgus antipodarum, in the Silver Creek watershed in Idaho, we investigated the distribution and dynamics of the snail populations over two years in field surveys. Despite extensive fishing and recreational activities in the watershed, the infestations appeared limited in extent. As with other published studies, densities of P. antipodarum were highest during summer months, but the distribution in Silver Creek was patchy. We found that near-to-below freezing winter water temperatures in localized reaches of the watershed were related to reduced populations or lack of detection. Distributions observed in winter were associated with regions of groundwater releases, or downstream of impoundments that dampened the temperature extremes observed in locations elsewhere in the watershed. We speculate that the population has remained restricted because thermal conditions are not conducive to year-round survival and growth. However, these relationships could be altered with watershed alterations or global climate change.

  3. Surface-water quality in agricultural watersheds of the North Carolina Coastal Plain associated with concentrated animal feeding operations

    Science.gov (United States)

    Harden, Stephen L.

    2015-01-01

    The effects of concentrated animal feeding operations (CAFOs) on water quality were investigated at 54 agricultural stream sites throughout the North Carolina Coastal Plain during 2012 and 2013. Three general watershed land-use types were examined during the study, including 18 background watersheds with no active CAFOs (BK sites), 18 watersheds with one or more active swine CAFOs but no poultry CAFOs (SW sites), and 18 watersheds with at least one active swine CAFO and one active dry-litter poultry CAFO (SP sites). The watershed drainage areas for these 54 stream sites ranged from 1.2 to 17.5 square miles. Conventional fertilizers used for crop production are the primary source of nutrients at the BK sites. Animal-waste manures represent an additional source of nutrients at the SW and SP study sites.

  4. Land use and water quality degradation in the Peixe-Boi River watershed

    Directory of Open Access Journals (Sweden)

    Bruno Wendell de Freitas Pereira

    2016-04-01

    Full Text Available This study mapped the land use and land cover of the catchment area of the Peixe-Boi River watershed, in northeast Pará, in order to identify conflicts of land use in the permanent preservation areas, and to relate them to water quality. We used LISS-3 sensor imagery from the Resourcesat satellite with a spatial resolution of 23.5 m for supervised classification of land use and land cover based on 22 training samples. Water quality was determined based on 28 sampling points in drainage network. The relationship between human disturbance and water quality was analyzed based on observations of land use changes using satellite imagery and in situ collection of water samples. The results show that 46% of the permanent preservation areas have conflicted uses, especially with respect to urban squatters, exposed soil and, most notably, pasture, with over 84 % of the area in conflict. Critical levels of dissolved oxygen reaching 2.14 mg L-1 and pH of 5.12 were observed in some sampling points. These values are below the fresh water standards set by Resolution 357/05 of CONAMA. The poorest water quality may be related to irregular use and occupation of areas within the permanent preservation areas. There is therefore an urgent need to develop a plan for the sustainable use and occupation of catchment area land in the Peixe-Boi River watershed in order to restore the environment and improve water quality.

  5. Future scenarios of urbanization and its effects on water quantity and quality in three New England watersheds

    Science.gov (United States)

    Hutyra, L.; Yang, Y.; Kim, J.; Cheng, C.; O'Brien, P.; Rouhani, S.; Douglas, E. M.; Nicolson, C.; Ryan, R.; Schaaf, C.; Warren, P.; Wollheim, W. M.

    2013-12-01

    New England watersheds have been impacted by human development and environmental stressors that are similar to those projected to impact large portions of the United States and the world. These impacts are likely to continue as some parts of the region are projected to lose over 60% of private forestland to development by 2030. Such dramatic changes have important consequences for water quality and quantity. Because of the complex and varied interactions between human and natural systems, simply understanding the processes affecting current and historical conditions in urbanizing watersheds is inadequate to model the future. Understanding future hydrologic conditions is made more difficult because of the uncertainties inherent in projecting future climate conditions. One approach to handling this complexity is to use scenarios to explore a range of potential futures following contrasting trajectories of change. Here we describe how four scenarios of land use change were developed using a stakeholder driven process. We then began using the scenarios in hydrological models to estimate future changes in water quality and quantity. The study area includes three watersheds (the Charles, Neponset and Ipswich) that have undergone varying degrees of urbanization in the greater Boston area of Massachusetts in the northeastern United States. The Charles and Neponset River watersheds are densely populated and include the city of Boston itself. Municipal water supplies in these two watersheds are mostly from the Massachusetts Water Resources Authority (MWRA) sources in western Massachusetts. The Ipswich River watershed is highly suburban, and communities are largely dependent on local water supplies. If the historical urbanization trends continue, the impervious area in the Charles River watershed is projected to increase by 13%, 16% in Neponset River watershed, and 24% in Ipswich River watershed by 2030. For the Charles River watershed, analyses identified hot spots for

  6. Watershed-scale Hydrology and Water Quality Impact of Switchgrass Intercropping in Southern Managed Pine Forests

    Science.gov (United States)

    Chescheir, G. M.; Birgand, F.; Allen, E.; Bennett, E.; Carter, T.; Dobbs, N.; Muwamba, A.; Amatya, D. M.; Youssef, M.; Nettles, J. E.

    2016-12-01

    The use of marginal land for cellulosic biofuel crop production is an attractive solution to preserve agricultural land for food production. The space available between rows of young loblolly pine (Pinus taeda) trees offers enough light to support growth of biofuel crops for several years. A five year field study was conducted to assess the hydrology and water quality impacts of switchgrass (Panicum virgatum) intercropping with pine trees in watersheds of the southeastern US. Paired-watershed studies were replicated in Mississippi and Alabama on upland sites, and in North Carolina on a flat lowland site. In each state, the impact of switchgrass intercropping was assessed from differences in water and nutrient yields from contiguous 20-40 ha watersheds established as: conventional young pine plantation, switchgrass intercropped in young pine plantation, switchgrass only, and mid-rotation mature pine plantation. A total of 14 watersheds were equipped with continuous flow monitoring stations, flow proportional water samplers, groundwater wells, soil moisture sensors and weather stations. Data collection continued through a two year pre-treatment period, a one year treatment period when field operations were conducted to establish switchgrass, and a two year post-treatment period when the established switchgrass was fertilized and harvested annually. Our results showed that significant increases in total suspended solids (TSS) and nitrogen (N) loading occurred during the treatment periods at the upland sites in MS and AL. During the post treatment periods, TSS and N loading decreased to levels near those observed in pretreatment. At the lowland site, only nitrogen loading was increased during the treatment period. Concentrations of TSS at the lowland site were two orders of magnitude lower than those observed at the upland sites and were not significantly affected by the treatment. Inherent flow variability between watersheds within sites made detection of subtle

  7. Energy, water and space use by free-living red kangaroos Macropus rufus and domestic sheep Ovis aries in an Australian rangeland.

    Science.gov (United States)

    Munn, A J; Dawson, T J; McLeod, S R; Dennis, T; Maloney, S K

    2013-08-01

    We used doubly labelled water to measure field metabolic rates (FMR) and water turnover rates (WTR) in one of Australia's largest native herbivores, the red kangaroo (Macropus rufus) and one of Australia's dominant livestock species, the wool-breed Merino sheep, under free-living conditions in a typical Australian rangeland. Also, we used GPS technology to examine animal space use, along with the comparisons of urine concentration, diet, diet digestibility, and subsequent grazing pressures. We found smaller space-use patterns than previously reported for kangaroos, which were between 14 and 25 % those of sheep. The FMR of a 25-kg kangaroo was 30 % that of a 45-kg sheep, while WTR was 15 % and both were associated with smaller travel distances, lower salt intakes, and higher urine concentration in kangaroos than sheep. After accounting for differences in dry matter digestibility of food eaten by kangaroos (51 %) and sheep (58 %), the relative grazing pressure of a standard (mature, non-reproductive) 25-kg kangaroo was 35 % that of a 45-kg sheep. Even for animals of the same body mass (35 kg), the relative grazing pressure of the kangaroo was estimated to be only 44 % that of the sheep. After accounting for the energetic costs of wool growth by sheep, the FMRs of our sheep and kangaroos were 2-3 times their expected BMRs, which is typical for mammalian FMR:BMRs generally. Notably, data collected from our free-living animals were practically identical to those from animals confined to a semi-natural enclosure (collected in an earlier study under comparable environmental conditions), supporting the idea that FMRs are relatively constrained within species.

  8. Accidental Water Pollution Risk Analysis of Mine Tailings Ponds in Guanting Reservoir Watershed, Zhangjiakou City, China.

    Science.gov (United States)

    Liu, Renzhi; Liu, Jing; Zhang, Zhijiao; Borthwick, Alistair; Zhang, Ke

    2015-12-02

    Over the past half century, a surprising number of major pollution incidents occurred due to tailings dam failures. Most previous studies of such incidents comprised forensic analyses of environmental impacts after a tailings dam failure, with few considering the combined pollution risk before incidents occur at a watershed-scale. We therefore propose Watershed-scale Tailings-pond Pollution Risk Analysis (WTPRA), designed for multiple mine tailings ponds, stemming from previous watershed-scale accidental pollution risk assessments. Transferred and combined risk is embedded using risk rankings of multiple routes of the "source-pathway-target" in the WTPRA. The previous approach is modified using multi-criteria analysis, dam failure models, and instantaneous water quality models, which are modified for application to multiple tailings ponds. The study area covers the basin of Gutanting Reservoir (the largest backup drinking water source for Beijing) in Zhangjiakou City, where many mine tailings ponds are located. The resultant map shows that risk is higher downstream of Gutanting Reservoir and in its two tributary basins (i.e., Qingshui River and Longyang River). Conversely, risk is lower in the midstream and upstream reaches. The analysis also indicates that the most hazardous mine tailings ponds are located in Chongli and Xuanhua, and that Guanting Reservoir is the most vulnerable receptor. Sensitivity and uncertainty analyses are performed to validate the robustness of the WTPRA method.

  9. Accidental Water Pollution Risk Analysis of Mine Tailings Ponds in Guanting Reservoir Watershed, Zhangjiakou City, China

    Science.gov (United States)

    Liu, Renzhi; Liu, Jing; Zhang, Zhijiao; Borthwick, Alistair; Zhang, Ke

    2015-01-01

    Over the past half century, a surprising number of major pollution incidents occurred due to tailings dam failures. Most previous studies of such incidents comprised forensic analyses of environmental impacts after a tailings dam failure, with few considering the combined pollution risk before incidents occur at a watershed-scale. We therefore propose Watershed-scale Tailings-pond Pollution Risk Analysis (WTPRA), designed for multiple mine tailings ponds, stemming from previous watershed-scale accidental pollution risk assessments. Transferred and combined risk is embedded using risk rankings of multiple routes of the “source-pathway-target” in the WTPRA. The previous approach is modified using multi-criteria analysis, dam failure models, and instantaneous water quality models, which are modified for application to multiple tailings ponds. The study area covers the basin of Gutanting Reservoir (the largest backup drinking water source for Beijing) in Zhangjiakou City, where many mine tailings ponds are located. The resultant map shows that risk is higher downstream of Gutanting Reservoir and in its two tributary basins (i.e., Qingshui River and Longyang River). Conversely, risk is lower in the midstream and upstream reaches. The analysis also indicates that the most hazardous mine tailings ponds are located in Chongli and Xuanhua, and that Guanting Reservoir is the most vulnerable receptor. Sensitivity and uncertainty analyses are performed to validate the robustness of the WTPRA method. PMID:26633450

  10. Accidental Water Pollution Risk Analysis of Mine Tailings Ponds in Guanting Reservoir Watershed, Zhangjiakou City, China

    Directory of Open Access Journals (Sweden)

    Renzhi Liu

    2015-12-01

    Full Text Available Over the past half century, a surprising number of major pollution incidents occurred due to tailings dam failures. Most previous studies of such incidents comprised forensic analyses of environmental impacts after a tailings dam failure, with few considering the combined pollution risk before incidents occur at a watershed-scale. We therefore propose Watershed-scale Tailings-pond Pollution Risk Analysis (WTPRA, designed for multiple mine tailings ponds, stemming from previous watershed-scale accidental pollution risk assessments. Transferred and combined risk is embedded using risk rankings of multiple routes of the “source-pathway-target” in the WTPRA. The previous approach is modified using multi-criteria analysis, dam failure models, and instantaneous water quality models, which are modified for application to multiple tailings ponds. The study area covers the basin of Gutanting Reservoir (the largest backup drinking water source for Beijing in Zhangjiakou City, where many mine tailings ponds are located. The resultant map shows that risk is higher downstream of Gutanting Reservoir and in its two tributary basins (i.e., Qingshui River and Longyang River. Conversely, risk is lower in the midstream and upstream reaches. The analysis also indicates that the most hazardous mine tailings ponds are located in Chongli and Xuanhua, and that Guanting Reservoir is the most vulnerable receptor. Sensitivity and uncertainty analyses are performed to validate the robustness of the WTPRA method.

  11. Contrasting Eutrophication Risks and Countermeasures in Different Water Bodies: Assessments to Support Targeted Watershed Management.

    Science.gov (United States)

    Li, Tong; Chu, Chunli; Zhang, Yinan; Ju, Meiting; Wang, Yuqiu

    2017-06-29

    Eutrophication is a major problem in China. To combat this issue, the country needs to establish water quality targets, monitoring systems, and intelligent watershed management. This study explores a new watershed management method. Water quality is first assessed using a single factor index method. Then, changes in total nitrogen/total phosphorus (TN/TP) are analyzed to determine the limiting factor. Next, the study compares the eutrophication status of two water function districts, using a comprehensive nutritional state index method and geographic information system (GIS) visualization. Finally, nutrient sources are qualitatively analyzed. Two functional water areas in Tianjin, China were selected and analyzed: Qilihai National Wetland Nature Reserve and Yuqiao Reservoir. The reservoir is a drinking water source. Results indicate that total nitrogen (TN) and total phosphorus (TP) pollution are the main factors driving eutrophication in the Qilihai Wetland and Yuqiao Reservoir. Phosphorus was the limiting factor in the Yuqiao Reservoir; nitrogen was the limiting factor in the Qilihai Wetland. Pollution in Qilihai Wetland is more serious than in Yuqiao Reservoir. The study found that external sources are the main source of pollution. These two functional water areas are vital for Tianjin; as such, the study proposes targeted management measures.

  12. LIMNOLOGY AND WATER QUALITY IN AN URBAN WATERSHED IN NORTH PANTANAL

    Directory of Open Access Journals (Sweden)

    Paulo Alexandre Jesus Gomes-Silva

    2016-04-01

    Full Text Available Studies focused on limnology and quality of water bodies are essential to produce data that support the planning and management, diagnose the current situation and propose measures to minimize the possible negative impacts on water resources. The Tereza Botas creek drains the town of Poconé-MT, situated in the Pantanal border. In this sense, the objective of this study was to verify the variations in limnological characteristics along the longitudinal gradient and evaluate the water quality of the Tereza Botas watershed, identifying the impacts from anthropogenic activities of this important Pantanal watershed. Four sampling points along the longitudinal gradient of the water stream have been defined, and physical, chemical and microbiological variables were analyzed. The results indicated that the changes in limnological and water quality derive from the riparian vegetation removal, erosion and discharge of sewage in natura. In addition, high density of E. coli was observed in most of the sampled points, demonstrating that the lack of proper sanitation as well as the presence of rudimentary cesspit are negatively affecting water quality in the headwaters region.

  13. Coupled effects of natural and anthropogenic controls on seasonal and spatial variations of river water quality during baseflow in a coastal watershed of Southeast China.

    Directory of Open Access Journals (Sweden)

    Jinliang Huang

    Full Text Available Surface water samples of baseflow were collected from 20 headwater sub-watersheds which were classified into three types of watersheds (natural, urban and agricultural in the flood, dry and transition seasons during three consecutive years (2010-2012 within a coastal watershed of Southeast China. Integrating spatial statistics with multivariate statistical techniques, river water quality variations and their interactions with natural and anthropogenic controls were examined to identify the causal factors and underlying mechanisms governing spatiotemporal patterns of water quality. Anthropogenic input related to industrial effluents and domestic wastewater, agricultural activities associated with the precipitation-induced surface runoff, and natural weathering process were identified as the potential important factors to drive the seasonal variations in stream water quality for the transition, flood and dry seasons, respectively. All water quality indicators except SRP had the highest mean concentrations in the dry and transition seasons. Anthropogenic activities and watershed characteristics led to the spatial variations in stream water quality in three types of watersheds. Concentrations of NH(4(+-N, SRP, K(+, COD(Mn, and Cl- were generally highest in urban watersheds. NO3(-N Concentration was generally highest in agricultural watersheds. Mg(2+ concentration in natural watersheds was significantly higher than that in agricultural watersheds. Spatial autocorrelations analysis showed similar levels of water pollution between the neighboring sub-watersheds exhibited in the dry and transition seasons while non-point source pollution contributed to the significant variations in water quality between neighboring sub-watersheds. Spatial regression analysis showed anthropogenic controls played critical roles in variations of water quality in the JRW. Management implications were further discussed for water resource management. This research

  14. High Nitrogen Fertilization of Tobacco Crop in Headwater Watershed Contaminates Subsurface and Well Waters with Nitrate

    OpenAIRE

    D. R. Kaiser; L. Sequinatto; Reinert,D. J.; Reichert,J. M.; D. S. Rheinheimer; Dalbianco, L.

    2015-01-01

    Our hypothesis was that subsurface and well waters in watershed with shallow, stony soils, steep landscapes, and cropped to tobacco are contaminated by nitrate. Nitrate in soil solution was monitored in (0.20 m) and below (0.5 m) root zone with tension lysimeters, in five transects. Water from two wells (beneath tobacco field and in native forest) used for human consumption was also analyzed for nitrate. Soil bulk density, porosity, and saturated hydraulic conductivity were evaluated. Soil ph...

  15. Spatial distribution of water erosion risk in a watershed with eucalyptus and Atlantic Forest

    Directory of Open Access Journals (Sweden)

    Junior Cesar Avanzi

    2013-10-01

    Full Text Available The process of water erosion occurs in watersheds throughout the world and it is strongly affected by anthropogenic influences. Thus, the knowledge of these processes is extremely necessary for planning of conservation efforts. This study was performed in an experimental forested watershed in order to predict the average potential annual soil loss by water erosion using the Universal Soil Loss Equation (USLE and a Geographic Information System (GIS, and then compared with soil loss tolerance. All the USLE factors were generated in a distributed approach employing a GIS tool. The layers were multiplied in the GIS framework in order to predict soil erosion rates. Results showed that the average soil loss was 6.2 Mg ha-1 yr-1. Relative to soil loss tolerance, 83% of the area had an erosion rate lesser than the tolerable value. According to soil loss classes, 49% of the watershed had erosion less than 2.5 Mg ha-1 yr-1. However, about 8.7% of the watershed had erosion rates greater than 15 Mg ha-1 yr-1, being mainly related to Plinthosol soil class and roads, thus requiring special attention for the improvement of sustainable management practices for such areas. Eucalyptus cultivation was found to have soil loss greater than Atlantic Forest. Thus, an effort should be made to bring the erosion rates closer to the native forest. Implementation of the USLE model in a GIS framework was found to be a simple and useful tool for predicting the spatial variation of soil erosion risk and identifying critical areas for conservation efforts.

  16. Groundwater—Surface Water Interactions in a Mountain-to-Coast Watershed: Effects of Climate Change and Human Stressors

    Directory of Open Access Journals (Sweden)

    S. B. Foster

    2015-01-01

    Full Text Available Watersheds located within a mountain to coast physiographic setting have been described as having a highly interconnected surface water and groundwater environment. The quantification of groundwater—surface water interactions at the watershed scale requires upscaling. This study uses MIKE SHE, a coupled numerical model, to explore the seasonally and spatially dynamic nature of these interactions in the Cowichan Watershed on Vancouver Island, British Columbia, Canada. The calibrated model simulates a transition of the Cowichan River from mostly gaining within the valley, to losing stream near the coast where groundwater extraction is focused. Losing and gaining sections correlate with geological substrate. Recharge across the watershed accounts for 17% of precipitation. Climate change is projected to lessen snowpack accumulation in the high alpine and alter timing of snowmelt, resulting in higher spring and winter river discharge and lower summer flows.

  17. The Rangeland Hydrology and Erosion Model: A Dynamic Approach for Predicting Soil Loss on Rangelands

    Science.gov (United States)

    Hernandez, Mariano; Nearing, Mark A.; Al-Hamdan, Osama Z.; Pierson, Frederick B.; Armendariz, Gerardo; Weltz, Mark A.; Spaeth, Kenneth E.; Williams, C. Jason; Nouwakpo, Sayjro K.; Goodrich, David C.; Unkrich, Carl L.; Nichols, Mary H.; Holifield Collins, Chandra D.

    2017-11-01

    In this study, we present the improved Rangeland Hydrology and Erosion Model (RHEM V2.3), a process-based erosion prediction tool specific for rangeland application. The article provides the mathematical formulation of the model and parameter estimation equations. Model performance is assessed against data collected from 23 runoff and sediment events in a shrub-dominated semiarid watershed in Arizona, USA. To evaluate the model, two sets of primary model parameters were determined using the RHEM V2.3 and RHEM V1.0 parameter estimation equations. Testing of the parameters indicated that RHEM V2.3 parameter estimation equations provided a 76% improvement over RHEM V1.0 parameter estimation equations. Second, the RHEM V2.3 model was calibrated to measurements from the watershed. The parameters estimated by the new equations were within the lowest and highest values of the calibrated parameter set. These results suggest that the new parameter estimation equations can be applied for this environment to predict sediment yield at the hillslope scale. Furthermore, we also applied the RHEM V2.3 to demonstrate the response of the model as a function of foliar cover and ground cover for 124 data points across Arizona and New Mexico. The dependence of average sediment yield on surface ground cover was moderately stronger than that on foliar cover. These results demonstrate that RHEM V2.3 predicts runoff volume, peak runoff, and sediment yield with sufficient accuracy for broad application to assess and manage rangeland systems.

  18. Topographic Wetness Indices, Soil Moisture, and Water Table Dynamics Identify Hydrologic Flow Paths in a Forest Watershed

    Science.gov (United States)

    Hofmeister, K.; Nave, L. E.; Drevnick, P. E.; Walter, M. T.

    2016-12-01

    Soil water is an essential hydrologic component linking water movement through a watershed with other hydrological, geological, and biological processes. Furthermore, soil water exists as water held in surface soil as well as shallow groundwater moving through the soil. Because soil moisture, shallow groundwater, and stream flow measurements in the field can be limited in spatial and temporal resolution due to constraints on resources, developing a relationship between point measurements and topographic wetness indices (TWIs) can allow for larger watershed or regional scale identification of saturated landscape areas and flow paths. We generated TWIs using topographic and soil data for a 120 ha forest watershed in northern Michigan. Field measurements of soil moisture, water table height, and stream flow were used to validate the TWIs as predictive maps of water storage and movement. TWIs successfully predicted spatial patterns of soil moisture and depth to water table at daily and seasonal scales. However, upland and wetland ecosystems showed fundamentally different relationships between observed soil moistures and TWI predictions. Temporal dynamics of soil moisture, shallow groundwater, and stream flow were linked seasonally during spring and fall recharge, and on a flashy event basis during the peak growing season. Collectively these results indicate that TWI maps can be effectively used to describe surface and shallow subsurface hydrology in this watershed, providing a hydrologic framework for watershed biogeochemistry research at this site.

  19. Water quality in watershed of the Jaboatão River (Pernambuco, Brazil: a case study

    Directory of Open Access Journals (Sweden)

    Souza Antonio Donizetti Gonçalves de

    2003-01-01

    Full Text Available The purpose of the present work was to evaluate anthropogenic influences on the water quality and to offer a subsidy to the establishment of water quality goals in the Jaboatão River Basin (Pernambuco State, Brazil. Eight sampling points were established and were sampled monthly during one hydrological cycle (March/98-February/99. The following variables were analyzed: temperature, pH, conductivity, chlorine, alkalinity, dissolved oxygen, biochemical oxygen demand, fecal coliforms, nitrate, total phosphorus and total solids. The most critical variables related to water quality objectives were dissolved oxygen, fecal coliforms and total phosphorus. Maps of land use, legally protected areas, area industries, and water withdrawals were utilized in order to propose division of the watershed into regions and to provide water quality management information.

  20. A Corresponding Study of Water Quality Evaluation of the Pasquotank Watershed in Northeastern North Carolina

    Science.gov (United States)

    Stevenson, J.; Walthall, S.; McKenzie, R.; Dixon, R.

    2015-12-01

    The Pasquotank River Watershed covers 450 sq miles in the Coastal Plain of NE North Carolina. It flows from the Great Dismal Swamp at the VA/NC border into the Albemarle Sound. The watershed provides a transition between spawning grounds and waters of the Albemarle Sound. Forested swamp wetlands border much of the waterways. Increased agricultural and urban development has greatly affected water quality during recent years. Test were completed along the tributaries and the river itself, adding to the previously data from 2011, 2013, and 2014. Streams tested were the Newbegun Creek, Knobbs Creek, Areneuse Creek, Mill Dam Creek, and Sawyers Creek. These streams cover a large area of the watershed and provide a wide variety of shore development from swampland and farmland to industrial development. Samples were tested for pH, salinity, total dissolved solids, and conductivity. Air/water temperature, dissolved oxygen, wind speed/direction, and turbidity/clarity measurements were taken in the field. The results were placed into an online database and correlated to the location of the sample using Google Maps®. Analysis tools were developed to compare the data from all years. Excel spreadsheets were developed to look more closely at individual points and tests for each point. This database was connected to a data visualization page utilizing Google Maps®. The results show variations for the individual water quality scores, but the overall water quality score for all the tested water sources remained at a comparable level from previous years. Mill Dam Creek rose above the previous three scores of 48 (2011), 47 (2013), and 49 (2014) and achieved a medium water quality score of 57. Areneuse Creek improved in water quality with a medium water quality score of 60. Sawyers Creek became the lowest scoring waterway tested at 35. Knobbs Creek decreased from previous years with a water quality score of 42. For a fourth consecutive testing year, Newbegun Creek fell within the

  1. Soil and Water Assessment Tool (SWAT) Applicability on Nutrients Loadings Prediction in Mountainous Lower Bear Malad River (LBMR) Watershed, Utah.

    Science.gov (United States)

    Salha, A. A.; Stevens, D. K.

    2014-12-01

    The application of watershed simulation models is indispensable when pollution is generated by a nonpoint source. These models should be able to simulate large complex watersheds with varying soils, land use and management conditions over long periods of time. This study presents the application of Soil and Water Assessment Tool (SWAT) to investigate, manage, and research the transport and fate of nutrients in (Subbasin HUC 16010204) Lower Bear Malad River (LBMR) watershed, Box elder County, Utah. Water quality problems arise primarily from high phosphorus and total suspended sediment concentrations that were caused by increasing agricultural and farming activities and complex network of canals and ducts of varying sizes and carrying capacities that transport water (for farming and agriculture uses). Using the available input data (Digital Elevation Model (DEM), land use/Land cover (LULC), soil map and weather and climate data for 20 years (1990-2010) to predict the water quantity and quality of the LBMR watershed using a spatially distributed model version of hydrological ArcSWAT model (ArcSWAT 2012.10_1.14). No previous studies have been found in the literature regarding an in-depth simulation study of the Lower Bear Malad River (LBMR) watershed to simulate stream flow and to quantify the associated movement of nitrogen, phosphorus, and sediment. It is expected that the model mainly will predict monthly mean total phosphorus (TP) concentration and loadings in a mountainous LBRM watershed (steep Wellsville mountain range with peak of (2,857 m)) having into consideration the snow and runoff variables affecting the prediction process. The simulated nutrient concentrations were properly consistent with observations based on the R2 and Nash- Sutcliffe fitness factors. Further, the model will be able to manage and assess the land application in that area with corresponding to proper BMPs regarding water quality management. Keywords: Water Quality Modeling; Soil and

  2. Effects of land use pattern on soil water in revegetation watersheds in semi-arid Chinese Loess Plateau

    Science.gov (United States)

    Yang, Lei; Chen, Liding; Wei, Wei

    2017-04-01

    Soil water stored below rainfall infiltration depth is a reliable water resource for plant growth in arid and semi-arid regions. For decreasing serious soil erosion, large-scale human-introduced vegetation restoration was initiated in Chinese Loess Plateau in late 1990s. However, these activities may result in excessive water consumption and soil water deficit if no appropriate scientific guidance were offered. This in turn impacts the regional ecological restoration and sustainable management of water resources. In this study, soil water content data in depth of 0-5 m was obtained by long-term field observation and geostatistical method in 6 small watersheds covered with different land use pattern. Profile characteristics and spatial-temporal patterns of soil water were compared between different land use types, hillslopes, and watersheds. The results showed that: (1) Introduced vegetation consumed excessive amount of water when compared with native grassland and farmland, and induced temporally stable soil desiccation in depth of 0-5 m. The introduced vegetation decreased soil water content to levels lower than the reference value representing no human impact in all soil layers. (2) The analysis of differences in soil water at hillslope and watershed scales indicated that land use determined the spatial and temporal variability of soil water. Soil water at watershed scale increased with the increasing area of farmland, and decreased with increasing percentage of introduced vegetation. Land use structure determined the soil water condition and land use pattern determined the spatial-temporal variability of soil water at watershed scale. (3) Large-scale revegetation with introduced vegetation diminished the spatial heterogeneity of soil water at different scales. Land use pattern adjustment could be used to improve the water resources management and maintain the sustainability of vegetation restoration.

  3. Effects of soil and water conservation on crop productivity: Evidences from Anjenie watershed, Ethiopia

    Science.gov (United States)

    Adgo, Enyew; Teshome, Akalu

    2014-05-01

    Widespread soil and water conservation activities have been implemented in many parts of eastern Africa to control soil erosion by water and improve land productivity for the last few decades. Following the 1974 severe drought, soil and water conservation became more important to Ethiopia and the approach shifted to watershed based land management initiatives since the 1980s. To capture long-term impacts of these initiatives, a study was conducted in Anjenie Watershed of Ethiopia, assessing fanya juu terraces and grass strips constructed in a pilot project in 1984, and which are still functional nearly 30 years later. Data were collected from government records, field observations and questionnaire surveys administered to 60 farmers. Half of the respondents had terraced farms in the watershed former project area (with terrace technology) and the rest were outside the terraced area. The crops assessed were teff, barley and maize. Cost-benefit analyses were used to determine the economic benefits with and without terraces, including gross and net profit values, returns on labour, water productivity and impacts on poverty. The results indicated that soil and water conservation had improved crop productivity. The average yield on terraced fields was 0.95 t ha-1 for teff (control 0.49), 1.86 t ha-1 for barley (control 0.61), and 1.73 t ha-1 for maize (control 0.77). The net benefit was significantly higher on terraced fields, recording US 20.9 (US -112 control) for teff, US 185 (US -41 control) for barley and US -34.5 (US - 101 control) ha-1 yr-1 for maize. The returns on family labour were 2.33 for barley, 1.01 for teff, and 0.739 US per person-day for maize grown on terraced plots, compared to US 0.44, 0.27 and 0.16 per person-day for plots without terraces, respectively. Using a discount rate of 10%, the average net present value (NPV) of barley production with terrace was found to be about US 1542 over a period of 50 years. In addition, the average financial

  4. Rangeland Hydrology and Erosion Model

    Science.gov (United States)

    Nearing, Mark; Pierson, Fred; Hernandez, Mariano; Al-Hamdan, Osama; Weltz, Mark; Spaeth, Ken; Wei, Haiyan; Stone, Jeff

    2013-04-01

    Soil loss rates on rangelands are considered one of the few quantitative indicators for assessing rangeland health and conservation practice effectiveness. An erosion model to predict soil loss specific for rangeland applications has been needed for many years. Most erosion models were developed from croplands where the hydrologic and erosion processes are different, largely due to much higher levels of heterogeneity in soil and plant properties at the plot scale and the consolidated nature of the soils. The Rangeland Hydrology and Erosion Model (RHEM) was designed to fill that need. RHEM is an event-based model that estimates runoff, erosion, and sediment delivery rates and volumes at the spatial scale of the hillslope and the temporal scale of a single rainfall event. It represents erosion processes under normal and fire-impacted rangeland conditions, it adopts a new splash erosion and thin sheet-flow transport equation developed from rangeland data, and it links the model hydrologic and erosion parameters with rangeland plant communities by providing a new system of parameter estimation equations based on 204 plots at 49 rangeland sites distributed across 15 western U.S. states. Recent work on the model is focused on representing intra-storm dynamics, using stream-power as the driver for detachment by flow, and deriving parameters for after-fire conditions.

  5. Primary factors affecting water quality and quantity in four watersheds in Eastern Puerto Rico

    Science.gov (United States)

    Murphy, Sheila F.; Stallard, Robert F.

    2009-01-01

    As part of the U.S. Geological Survey (USGS) Water, Energy, and Biogeochemical Budgets (WEBB) program, four small watersheds in eastern Puerto Rico were monitored to identify and evaluate the effects of geology, landcover, atmospheric deposition, and other factors on stream water quality and quantity. Two catchments are located on coarse-grained granitic plutonic rocks, which weather to quartz- and clay-rich, sandy soils, and two are located on fine-grained volcanic rocks and volcaniclastic sediments, which weather to quartz-poor, fine-grained soils. These differing soil materials result in different hydrologic regimes. Soils on the granitic rocks have greater permeability than those developed on the volcaniclastic rocks, allowing more water infiltration and potentially greater landslide erosion rates. For each bedrock type, one catchment was covered with mature rainforest, and the other catchment was affected by agricultural practices typical of eastern Puerto Rico. These practices led to the erosion of much of the original surface soil in the agricultural watersheds, which introduced large quantities of sediment to stream channels. The agricultural watersheds are undergoing natural reforestation, like much of Puerto Rico. Eastern Puerto Rico receives large atmospheric inputs of marine salts, pollutants from the Northern Hemisphere, and Saharan Desert dust. Marine salts contribute over 80 percent of the ionic charge in precipitation, with peak inputs in January. Intense storms, mostly hurricanes, are associated with exceptionally high chloride concentrations in stream waters. Temperate pollution contributes nitrate, ammonia, and sulfate, with maximum inputs during northern cold fronts in January, April, and May. Pollution inputs have increased through time. Desert dust peaks in June and July, during times of maximum dust transport from the Saharan Desert across the Atlantic Ocean.

  6. Adopt Your Watershed

    Data.gov (United States)

    U.S. Environmental Protection Agency — Adopt Your Watershed is a Website that encourages stewardship of the nation's water resources and serves as a national inventory of local watershed groups and...

  7. Healthy Watersheds Protection

    Science.gov (United States)

    ... provide critical services, such as clean drinking water, productive fisheries, and outdoor recreation, that support our economies, ... Watershed Assessments Integrated Assessment of Watershed Condition Protection Projects and Partnerships Additional Resources Main menu Environmental Topics ...

  8. Water, energy, and biogeochemical budgets investigation at Panola Mountain research watershed, Stockbridge, Georgia; a research plan

    Science.gov (United States)

    Huntington, T.G.; Hooper, R.P.; Peters, N.E.; Bullen, T.D.; Kendall, Carol

    1993-01-01

    The Panola Mountain Research Watershed (PMRW), located in the Panola Mountain State Conservation Park near Stockbridge, Georgia has been selected as a core research watershed under the Water, Energy and Biogeochemical Budgets (WEBB) research initiative of the U.S. Geological Survey (USGS) Global Climate Change Program. This research plan describes ongoing and planned research activities at PMRW from 1984 to 1994. Since 1984, PMRW has been studied as a geochemical process research site under the U.S. Acid Precipitation Thrust Program. Research conducted under this Thrust Program focused on the estimation of dry atmospheric deposition, short-term temporal variability of streamwater chemistry, sulfate adsorption characteristics of the soils, groundwater chemistry, throughfall chemistry, and streamwater quality. The Acid Precipitation Thrust Program continues (1993) to support data collection and a water-quality laboratory. Proposed research to be supported by the WEBB program is organized in 3 interrelated categories: streamflow generation and water-quality evolution, weathering and geochemical evolution, and regulation of soil-water chemistry. Proposed research on streamflow generation and water-quality evolution will focus on subsurface water movement, its influence in streamflow generation, and the associated chemical changes of the water that take place along its flowpath. Proposed research on weathering and geochemical evolution will identify the sources of cations observed in the streamwater at Panola Mountain and quantify the changes in cation source during storms. Proposed research on regulation of soil-water chemistry will focus on the poorly understood processes that regulate soil-water and groundwater chemistry. (USGS)

  9. Geophysical imaging of watershed subsurface patterns and prediction of soil texture and water holding capacity

    Science.gov (United States)

    Abdu, H.; Robinson, D. A.; Seyfried, M.; Jones, S. B.

    2008-04-01

    The spatial distribution of subsurface soil textural properties across the landscape is an important control on the hydrological and ecological function of a watershed. Traditional methods of mapping soils involving subjective assignment of soil boundaries are inadequate for studies requiring a quantitative assessment of the landscape and its subsurface connectivity and storage capacity. Geophysical methods such as electromagnetic induction (EMI) provide the possibility of obtaining high-resolution images across a landscape to identify subtle changes in subsurface soil patterns. In this work we show how EMI can be used to image the subsurface of a ˜38 ha watershed. We present an imaging approach using kriging to interpolate and sequential Gaussian simulation to estimate the uncertainty in the maps. We also explore the idea of difference ECa mapping to try to exploit changes in soil moisture to identify more hydrologically active locations. In addition, we use a digital elevation model to identify flow paths and compare these with the ECa measurement as a function of distance. Finally, we perform a more traditional calibration of ECa with clay percentage across the watershed and determine soil water holding capacity (SWHC). The values of SWHC range from 0.07 to 0.22 m3 m-3 across the watershed, which contrast with the uniform value of 0.13 derived from the traditional soil survey maps. Additional work is needed to appropriately interpret and incorporate EMI data into hydrological studies; however, we argue that there is considerable merit in identifying subsurface soil patterns from these geophysical images.

  10. Hydrology and climate of four watersheds in eastern Puerto Rico: Chapter C in Water quality and landscape processes of four watersheds in eastern Puerto Rico

    Science.gov (United States)

    Murphy, Sheila F.; Stallard, Robert F.; Murphy, Sheila F.; Stallard, Robert F.

    2012-01-01

    Puerto Rico lies directly in the path of the easterly trade winds, which deliver steady rainfall to the mountains and steer tropical wave systems toward the island. Hurricanes and tropical storms derived from these tropical waves differ in frequency and intensity, contributing to substantial interannual variation in precipitation and stream discharge. Puerto Rico's steep topography and small water-storage capacity leave the island's water supply and developed flood plains vulnerable to extreme weather events, such as hurricanes, floods, and droughts. This vulnerability may increase in the future owing to ongoing change, both local (such as land-cover shifts, water-supply projects, and construction of roads and other infrastructure) and regional (climate variability and change). Climate change, which could lead to more intense and prolonged droughts as well as an increase in the magnitude and frequency of destructive storms in the Caribbean, may alter temperature and affect the availability of water for human and ecosystem needs. Accurate assessment of hydrologic regimes and water budgets is therefore crucial for effective management of water resources. As part of the U.S. Geological Survey's Water, Energy, and Biogeochemical Budgets program, hydrologic and geomorphologic processes and stream chemistry of four small watersheds in eastern Puerto Rico, which differ in geology and land cover, have been studied since 1991. Spatial and temporal characteristics of precipitation and stream discharge, along with water budgets, were determined for the watersheds for the period 1991 to 2005. The locations of the watersheds relative to the Luquillo Mountains and the range's associated rain shadow dominate hydrological processes, dwarfing influences of land cover. The influence of geology is reflected in recession characteristics of the rivers (recession is faster in soils overlying volcaniclastic bedrock) and in hillslope geomorphic processes (sediment is delivered at higher

  11. Water quality mapping of Laguna de Bay and its watershed, Philippines

    Science.gov (United States)

    Saito, S.; Nakano, T.; Shin, K.; Maruyama, S.; Miyakawa, C.; Yaota, K.; Kada, R.

    2011-12-01

    Laguna de Bay (or Laguna Lake) is the largest lake in the Philippines, with a surface area of 900 km2 and its watershed area of 2920 km2 (Santos-Borja, 2005). It is located on the southwest part of the Luzon Island and its watershed contains 5 provinces, 49 municipalities and 12 cities, including parts of Metropolitan Manila. The water quality in Laguna de Bay has significantly deteriorated due to pollution from soil erosion, effluents from chemical industries, and household discharges. In this study, we performed multiple element analysis of water samples in the lake and its watersheds for chemical mapping, which allows us to evaluate the regional distribution of elements including toxic heavy metals such as Cd, Pb and As. We collected water samples from 24 locations in Laguna de Bay and 160 locations from rivers in the watersheds. The sampling sites of river are mainly downstreams around the lake, which covers from urbanized areas to rural areas. We also collected well water samples from 17 locations, spring water samples from 10 locations, and tap water samples from 21 locations in order to compare their data with the river and lake samples and to assess the quality of household use waters. The samples were collected in dry season of the study area (March 13 - 17 and May 2 - 9, 2011). The analysis was performed at the Research Institute for Humanity and Nature (RIHN), Japan. The concentrations of the major components (Cl, NO3, SO4, Ca, Mg, Na, and K) dissolved in the samples were determined with ion chromatograph (Dionex Corporation ICS-3000). We also analyzed major and trace elements (Li, B, Na, Mg, Al, Si, P, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn Ga, Ge, As, Se, Rb, Sr, Y, Zr, Mo, Ag, Cd, Sn, Sb, Cs, Ba, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, W, Pb and U) with inductively coupled plasma-mass spectrometry (ICP-MS, Agilent Technologies 7500cx). The element concentrations of rivers are characterized by remarkable regional variations. For

  12. Fractal water quality fluctuations spanning the periodic table in an intensively farmed watershed.

    Science.gov (United States)

    Aubert, Alice H; Kirchner, James W; Gascuel-Odoux, Chantal; Faucheux, Mikael; Gruau, Gérard; Mérot, Philippe

    2014-01-21

    Recently developed measurement technologies can monitor surface water quality almost continuously, creating high-frequency multiparameter time series and raising the question of how best to extract insights from such rich data sets. Here we use spectral analysis to characterize the variability of water quality at the AgrHys observatory (Western France) over time scales ranging from 20 min to 12 years. Three years of daily sampling at the intensively farmed Kervidy-Naizin watershed reveal universal 1/f scaling for all 36 solutes, yielding spectral slopes of 1.05 ± 0.11 (mean ± standard deviation). These 36 solute concentrations show varying degrees of annual cycling, suggesting different controls on watershed export processes. Twelve years of daily samples of SO4, NO3, and dissolved organic carbon (DOC) show that 1/f scaling does not continue at frequencies below 1/year in those constituents, whereas a 12-year daily record of Cl shows a general 1/f trend down to the lowest measurable frequencies. Conversely, approximately 12 months of 20 min NO3 and DOC measurements show that at frequencies higher than 1/day, the spectra of these solutes steepen to slopes of roughly 3, and at time scales shorter than 2-3 h, the spectra flatten to slopes near zero, reflecting analytical noise. These results confirm and extend the recent discovery of universal fractal 1/f scaling in water quality at the relatively pristine Plynlimon watershed in Wales, further demonstrating the importance of advective-dispersive transport mixing in catchments. However, the steeper scaling at subdaily time scales suggests additional short-term damping of solute concentrations, potentially due to in-stream or riparian processes.

  13. Environmental controls on the spatial variability of soil water dynamics in a small watershed

    Science.gov (United States)

    Hu, Wei; Chau, Henry Wai; Qiu, Weiwen; Si, Bingcheng

    2017-08-01

    Soil water content (SWC) in the root zone is controlled by a suite of environmental variables. Complication arises from the cross-correlation between these environmental variables. Therefore, there is still a poor understanding on the controls of root zone SWC dynamics due, in part, to a lack of an appropriate method to untangle the controls. The objective of this study was to reveal the dominant controls of root zone soil water dynamics in a small watershed using an appropriate method based on empirical orthogonal function (EOF). For this purpose, SWC of 0-0.8 m layer in a small watershed on the Chinese Loess Plateau was used. The space-variant temporal anomaly (Rtn) of SWC, which is responsible for the spatial variability of soil water dynamics, was decomposed using the EOF. Results indicated that 86% of the total variations of Rtn were explained by three significant spatial structures (EOFs). Sand content and grass yield dominated the EOF1 of Rtn and elevation and aspect dominated EOF2 and EOF3 of Rtn , respectively. Moreover, their effects on soil water dynamics were time-dependent. The EOF analysis showed that three independent groups of factors (i.e., soil and vegetation dominated earth surface condition, elevation related near surface air humidity, and aspect regulated energy input) may drive the variability in soil water dynamics. Traditional correlation analysis, however, indicated that SWC was greater at higher elevation and sun-facing slopes, which distorted the soil water dynamics controls. Although original SWC-based partial correlation basically supported our findings, the results highly depended on the controlling factors selected. This study implied that Rtn rather than original SWC should be preferred for understanding soil water dynamics controls.

  14. Low-flow water-quality characterization of the Gore Creek watershed, upper Colorado River basin, Colorado, August 1996

    Science.gov (United States)

    Wynn, Kirby H.; Spahr, Norman E.

    1998-01-01

    The Upper Colorado River Basin (UCOL) is one of 59 National Water-Quality Assessment (NAWQA) study units designed to assess the status and trends of the Nation?s water quality (Leahy and others, 1990). The UCOL study unit began operation in 1994, and surface-water-quality data collection at a network of 14 sites began in October 1995 (Apodaca and others, 1996; Spahr and others, 1996). Gore Creek, which flows through Vail, Colorado, originates in pristine alpine headwaters and is designated a gold-medal trout fishery. The creek drains an area of about 102 square miles and is a tributary to the Eagle River. Gore Creek at the mouth near Minturn (site 13 in fig. 1) is one of the 14 sites in the UCOL network. This site was selected to evaluate water quality resulting from urban development and recreational land use. The Gore Creek watershed has undergone rapid land-use changes since the 1960?s as the Vail area shifted from traditional mountain ranchlands to a four-season resort community. Residential, recreational, commercial, and transportation development continues near Gore Creek and its tributaries to support the increasing permanent and tourist population of the area. Interstate 70 runs through the watershed from Vail Pass near site 14, along the eastern side of Black Gore Creek, and along the northern side of the main stem of Gore Creek to the mouth of the watershed (fig. 1). A major local concern is how increasing urbanization/recreation affects the water quality, gold-medal trout fishery, and aesthetic values of Gore Creek. An evaluation of the spatial characteristics of water quality in the watershed upstream from site 13 at the mouth of Gore Creek (fig. 1) can provide local water and land managers with information necessary to establish water policy and make land-use planning decisions to maintain or improve water quality. Historical data collected at the mouth of Gore Creek provide information about water quality resulting from land use, but a synoptic

  15. Parameterization of the Rangeland Hydrology and Erosion Model (RHEM) Using Dynamic Landsat-Based Foliar Cover Estimates

    Science.gov (United States)

    Kautz, M. A.; Holifield Collins, C.; Guertin, D. P.; Goodrich, D. C.; Van Leeuwen, W. J. D.

    2016-12-01

    Changes in watershed vegetative cover from natural and anthropogenic causes including, climatic fluctuation, wildfires and land management practices, can result in increased surface water runoff and erosion. Hydrologic models play an important role in the decision support process for managing these landscape alterations. However, model parameterization requires quantified measures of watershed biophysical condition to generate accurate results. These inputs are often obtained from nationally available land cover data sets that are static in terms of vegetation condition and phenology. Obtaining vegetative data for model input of sufficient spatiotemporal resolution for long-term, watershed-scale change analysis has been a challenge. The purpose of this research was to assess the implications of parameterizing the event-based, Rangeland Hydrology and Erosion Model (RHEM) with dynamic, remotely sensed foliar cover data. The study was conducted on a small, instrumented grassland watershed within the Walnut Gulch Experimental Watershed surrounding Tombstone, Arizona. A time series of foliar cover rasters was produced by calibrating Landsat-based Soil-Adjusted Total Vegetation Index (SATVI) scenes with field transect measurements. Estimates of basal and litter cover were calculated using allometric relationships derived from the transect data. RHEM was parameterized using these remotely sensed inputs for all recorded runoff events from 1996-2014. Model performance was improved using the dynamic foliar cover compared to using a static, long-term mean foliar cover value. Significant (plitter cover. The integration of Landsat-based vegetative data into RHEM allows for modelling on a broadened spatiotemporal scale, resulting in improved landscape characterization and the ability to track watershed response to long-term vegetation changes.

  16. Influence of forest and rangeland management on anadromous fish habitat in Western North America: water transportation and storage of logs.

    Science.gov (United States)

    J.R. Sedell; W.S. Duval

    1985-01-01

    Environmental effects of water transportation of logs in western North America include the historical driving of logs in rivers and streams, and the current dumping, sorting, transportation, and storage of logs in rivers and estuaries in British Columbia and southeastern Alaska. The historical discussion focuses on habitat losses and volumes of...

  17. Application of the Water Erosion Prediction Project (WEPP) Model to simulate streamflow in a PNW forest watershed

    Science.gov (United States)

    A. Srivastava; M. Dobre; E. Bruner; W. J. Elliot; I. S. Miller; J. Q. Wu

    2011-01-01

    Assessment of water yields from watersheds into streams and rivers is critical to managing water supply and supporting aquatic life. Surface runoff typically contributes the most to peak discharge of a hydrograph while subsurface flow dominates the falling limb of hydrograph and baseflow contributes to streamflow from shallow unconfined aquifers primarily during the...

  18. Post-Fire soil water repellency, hydrologic response, and sediment yield compared between grass-converted and chaparral watersheds

    Science.gov (United States)

    Ken R. Hubbert; Pete M. Wohlgemuth; Jan L. Beyers; Marcia G. Narog; Ross Gerrard

    2012-01-01

    In 2002, the Williams Fire burned >90 % of the San Dimas Experimental Forest, providing an opportunity to investigate differences in soil water repellency, peak discharge, and sediment yield between grass-converted and chaparral watersheds. Post-fire water repellency and moisture content were measured in the winter and summer for four years. Peak discharge was...

  19. Sensitivity of stream flow and water table depth to potential climatic variability in a coastal forested watershed

    Science.gov (United States)

    Zhaohua Dai; Carl Trettin; Changsheng Li; Devendra M. Amatya; Ge Sun; Harbin Li

    2010-01-01

    A physically based distributed hydrological model, MIKE SHE, was used to evaluate the effects of altered temperature and precipitation regimes on the streamflow and water table in a forested watershed on the southeastern Atlantic coastal plain. The model calibration and validation against both streamflow and water table depth showed that the MIKE SHE was applicable for...

  20. Prescribed burning effects on soil physical properties and soil water repellency in a steep chaparral watershed, southern California, USA

    Science.gov (United States)

    K.R. Hubbert; H.K. Preisler; P.M. Wohlgemuth; R.C. Graham; M.G. Narog

    2006-01-01

    Chaparral watersheds associated with Mediterranean-type climate are distributed over five regions of the world. Because brushland soils are often shallow with low water holding capacities, and are on slopes prone to erosion, disturbances such as fire can adversely affect their physical properties. Fire can also increase the spatial coverage of soil water repellency,...

  1. Development of An Empirical Water Quality Model for Stormwater Based on Watershed Land Use in Puget Sound

    Energy Technology Data Exchange (ETDEWEB)

    Cullinan, Valerie I.; May, Christopher W.; Brandenberger, Jill M.; Judd, Chaeli; Johnston, Robert K.

    2007-03-29

    The Sinclair and Dyes Inlet watershed is located on the west side of Puget Sound in Kitsap County, Washington, U.S.A. (Figure 1). The Puget Sound Naval Shipyard (PSNS), U.S Environmental Protection Agency (USEPA), the Washington State Department of Ecology (WA-DOE), Kitsap County, City of Bremerton, City of Bainbridge Island, City of Port Orchard, and the Suquamish Tribe have joined in a cooperative effort to evaluate water-quality conditions in the Sinclair-Dyes Inlet watershed and correct identified problems. A major focus of this project, known as Project ENVVEST, is to develop Water Clean-up (TMDL) Plans for constituents listed on the 303(d) list within the Sinclair and Dyes Inlet watershed. Segments within the Sinclair and Dyes Inlet watershed were listed on the State of Washington’s 1998 303(d) because of fecal coliform contamination in marine water, metals in sediment and fish tissue, and organics in sediment and fish tissue (WA-DOE 2003). Stormwater loading was identified by ENVVEST as one potential source of sediment contamination, which lacked sufficient data for a contaminant mass balance calculation for the watershed. This paper summarizes the development of an empirical model for estimating contaminant concentrations in all streams discharging into Sinclair and Dyes Inlets based on watershed land use, 18 storm events, and wet/dry season baseflow conditions between November 2002 and May 2005. Stream pollutant concentrations along with estimates for outfalls and surface runoff will be used in estimating the loading and ultimately in establishing a Water Cleanup Plan (TMDL) for the Sinclair-Dyes Inlet watershed.

  2. Application of a water balance model for estimating deep infiltration in a karstic watershed

    Directory of Open Access Journals (Sweden)

    Maria Lúcia Calijuri

    2011-12-01

    Full Text Available The current scenario of water scarcity evidences the need for an adequate management of water resources. In karstic regions, the water flow through fractures significantly increases the water infiltration rate, which explains the small number of rivers and the importance of groundwater for urban supply. Therefore, the water balance is necessary since it may aid decision making processes and guide water management projects. The objective of this paper was to perform the water balance of a watershed situated in a karstic region quantifying infiltration, runoff and evapotranspiration. The study area is located near the Tancredo Neves International Airport in Confins, in the state of Minas Gerais, Brazil. Most of the area consists of forest formations (40.9%, and pastures (34.5%. In order to estimate deep infiltration, the BALSEQ model was used. BALSEQ is a numeric model of sequential water balance in which deep infiltration at the end of the day is given by the difference between daily precipitation and the sum of surface runoff, evapotranspiration and the variation of the amount of water stored in the soil. The results show that approximately 60% of total annual precipitation result in deep infiltration, considering the recharge period from September to March. After the dry period, the areas with no vegetal cover present higher deep infiltration. However, over the months, the contribution of the vegetated areas becomes greater, showing the importance of these areas to aquifer recharge.

  3. Assessment of Water Supply as an Ecosystem Service in a Rural-Urban Watershed in Southwestern Mexico City

    Science.gov (United States)

    Jujnovsky, Julieta; González-Martínez, Teresa Margarita; Cantoral-Uriza, Enrique Arturo; Almeida-Leñero, Lucia

    2012-03-01

    Studies from the ecosystem services perspective can provide a useful framework because they allow us to fully examine the benefits that humans obtain from socio-ecological systems. Mexico City, the second largest city in the world, has faced severe problems related to water shortages, which have worsened due to increasing population. Demand for space has forced changes in land cover, including covering areas that are essential for groundwater recharge. The city has 880 km2 of forest areas that are crucial for the water supply. The Magdalena River Watershed was chosen as a model because it is a well-preserved zone within Mexico City and it provides water for the population. The general aim of this study was to assess the ecosystem service of the water supply in the Magdalena River Watershed by determining its water balance (SWAT model) and the number of beneficiaries of the ecosystem services. The results showed that the watershed provides 18.4 hm3 of water per year. Baseflow was dominant, with a contribution of 85%, while surface runoff only accounted for 15%. The zone provides drinking water to 78,476 inhabitants and could supply 153,203 potential beneficiaries. This work provides an example for understanding how ecosystem processes determine the provision of ecosystem services and benefits to the population in a rural-urban watershed in Mexico City.

  4. Development of Optimal Water-Resources Management Strategies for Kaidu-Kongque Watershed under Multiple Uncertainties

    Directory of Open Access Journals (Sweden)

    Y. Zhou

    2013-01-01

    Full Text Available In this study, an interval-stochastic fractile optimization (ISFO model is advanced for developing optimal water-resources management strategies under multiple uncertainties. The ISFO model can not only handle uncertainties presented in terms of probability distributions and intervals with possibility distribution boundary, but also quantify subjective information (i.e., expected system benefit preference and risk-averse attitude from different decision makers. The ISFO model is then applied to a real case of water-resources systems planning in Kaidu-kongque watershed, China, and a number of scenarios with different ecological water-allocation policies under varied p-necessity fractiles are analyzed. Results indicate that different policies for ecological water allocation can lead to varied water supplies, economic penalties, and system benefits. The solutions obtained can help decision makers identify optimized water-allocation alternatives, alleviate the water supply-demand conflict, and achieve socioeconomic and ecological sustainability, particularly when limited water resources are available for multiple competing users.

  5. Application of the SUSTAIN Model to a Watershed-Scale Case for Water Quality Management

    Directory of Open Access Journals (Sweden)

    Chi-Feng Chen

    2014-11-01

    Full Text Available Low impact development (LID is a relatively new concept in land use management that aims to maintain hydrological conditions at a predevelopment level without deteriorating water quality during land development. The United States Environmental Protection Agency (USEPA developed the System for Urban Stormwater Treatment and Analysis Integration model (SUSTAIN to evaluate the performance of LID practices at different spatial scales; however, the application of this model has been limited relative to LID modeling. In this study, the SUSTAIN model was applied to a Taiwanese watershed. Model calibration and verification were performed, and different types of LID facilities were evaluated. The model simulation process and the verified model parameters could be used in other cases. Four LID scenarios combining bioretention ponds, grass swales, and pervious pavements were designed based on the land characteristics. For the SUSTAIN model simulation, the results showed that pollution reduction was mainly due to water quantity reduction, infiltration was the dominant mechanism and plant interception had a minor effect on the treatment. The simulation results were used to rank the primary areas for nonpoint source pollution and identify effective LID practices. In addition to the case study, a sensitivity analysis of the model parameters was performed, showing that the soil infiltration rate was the most sensitive parameter affecting the LID performance. The objectives of the study are to confirm the applicability of the SUSTAIN model and to assess the effectiveness of LID practices in the studied watershed.

  6. Physical habitat and water quality correlates of crayfish distributions in a mined watershed

    Science.gov (United States)

    Welsh, Stuart; Loughman, Zachary J.

    2014-01-01

    In mined watersheds, water quality alters aquatic faunas, but few studies have focused on associations between stream habitat and crayfish distributions. We examined associations of water quality and physical habitat quality on presence/absence of six crayfish species in the upper Kanawha River drainage of southern West Virginia, USA, a region with a long history of surface and mountaintop removal mining of coal. Data supported an association of physical habitat quality with the presence of four species (Cambarus carinirostris, Cambarus robustus, Cambarus cf. sciotensis, and Orconectes sanbornii). Cambarus bartonii cavatus and the non-native Orconectes virilis were associated with lower quality physical habitat than that of the other four species. Relative to other species, C. b. cavatus was associated with the lowest conductivity values, whereas O. virilis was associated with the highest conductivity values. Secondary and tertiary burrowers were generally associated with relatively high-quality physical habitat. However, C. b. cavatus, a crayfish known to burrow extensively in headwater streams, was associated with the lowest quality physical habitat. Physical habitat quality was generally supported over stream conductivity as a variable influencing crayfish distributions. Our data demonstrate the importance of stream habitat quality when assessing crayfish assemblages within mined watersheds.

  7. Weathering, landscape equilibrium, and carbon in four watersheds in eastern Puerto Rico: Chapter H in Water quality and landscape processes of four watersheds in eastern Puerto Rico

    Science.gov (United States)

    Stallard, Robert F.; Murphy, Sheila F.; Stallard, Robert F.

    2012-01-01

    The U.S. Geological Survey's Water, Energy, and Biogeochemical Budgets (WEBB) program research in eastern Puerto Rico involves a double pair-wise comparison of four montane river basins, two on granitic bedrock and two on fine-grained volcaniclastic bedrock; for each rock type, one is forested and the other is developed. A confounding factor in this comparison is that the developed watersheds are substantially drier than the forested (runoff of 900–1,600 millimeters per year compared with 2,800–3,700 millimeters per year). To reduce the effects of contrasting runoff, the relation between annual runoff and annual constituent yield were used to estimate mean-annual yields at a common, intermediate mean-annual runoff of 1,860 millimeters per year. Upon projection to this intermediate runoff, the ranges of mean-annual yields among all watersheds became more compact or did not substantially change for dissolved bedrock, sodium, silica, chloride, dissolved organic carbon, and calcium. These constituents are the primary indicators of chemical weathering, biological activity on the landscape, and atmospheric inputs; the narrow ranges indicate little preferential influence by either geology or land cover. The projected yields of biologically active constituents (potassium, nitrate, ammonium ion, phosphate), and particulate constituents (suspended bedrock and particulate organic carbon) were considerably greater for developed landscapes compared with forested watersheds, consistent with the known effects of land clearing and human waste inputs. Equilibrium rates of combined chemical and physical weathering were estimated by using a method based on concentrations of silicon and sodium in bedrock, river-borne solids, and river-borne solutes. The observed rates of landscape denudation greatly exceed rates expected for a dynamic equilibrium, except possibly for the forested watershed on volcaniclastic rock. Deforestation and agriculture can explain the accelerated physical

  8. Water-limiting conditions based on monthly water balances and potential evapotranspiration at Panola Mountain Research Watershed, Georgia, U.S.A

    Science.gov (United States)

    Brent Aulenbach; Norman E. Peters; James Freer

    2016-01-01

    Drought and resulting water-limiting conditions can result in negative ecological impacts such as reduced plant growth and increased stress that can make plants more vulnerable to threats such as insect infestations. The long-term dataset at Panola Mountain Research Watershed, a small 0.41-hectare forested watershed near Atlanta, Georgia, U.S.A., was used to better ...

  9. Combine the soil water assessment tool (SWAT) with sediment geochemistry to evaluate diffuse heavy metal loadings at watershed scale.

    Science.gov (United States)

    Jiao, Wei; Ouyang, Wei; Hao, Fanghua; Huang, Haobo; Shan, Yushu; Geng, Xiaojun

    2014-09-15

    Assessing the diffuse pollutant loadings at watershed scale has become increasingly important when formulating effective watershed water management strategies, but the process was seldom achieved for heavy metals. In this study, the overall temporal-spatial variability of particulate Pb, Cu, Cr and Ni losses within an agricultural watershed was quantitatively evaluated by combining SWAT with sediment geochemistry. Results showed that the watershed particulate heavy metal loadings displayed strong variability in the simulation period 1981-2010, with an obvious increasing trend in recent years. The simulated annual average loadings were 20.21 g/ha, 21.75 g/ha, 47.35 g/ha and 21.27 g/ha for Pb, Cu, Cr and Ni, respectively. By comparison, these annual average values generally matched the estimated particulate heavy metal loadings at field scale. With spatial interpolation of field loadings, it was found that the diffuse heavy metal pollution mainly came from the sub-basins dominated with cultivated lands, accounting for over 70% of total watershed loadings. The watershed distribution of particulate heavy metal losses was very similar to that of soil loss but contrary to that of heavy metal concentrations in soil, highlighting the important role of sediment yield in controlling the diffuse heavy metal loadings. Copyright © 2014 Elsevier B.V. All rights reserved.

  10. Linking High Frequency Variations in Stream Water DOC to Ages of Water Sources in Peat-Dominated Montane Watersheds

    Science.gov (United States)

    Tunaley, C.; Tetzlaff, D.; Lessels, J. S.; Soulsby, C.

    2015-12-01

    We combined time series of inferred DOC (from optical sensors) and stable isotopes in streams and watershed source areas to assess the link between water age and C fluxes. We monitored temporal dynamics of FDOM for 2 yrs at nested scales (0.9, 3.0 and 30km2) in a montane Scottish watershed. FDOM was strongly correlated (r2 ~ 0.8) with DOC allowing inference of 15 min timeseries. Marked seasonality was observed, with highest DOC concentrations (~25 mg l-1) in summer events and lower concentrations (~5mg l-1) in winter. During events, anticlockwise hysteresis was observed; consistent with expansion of the riparian saturation zone, increasing hydrological connectivity across peat soils and mobilizing DOC. Lag times for peak discharge and DOC were 1-12 hrs depending on event characteristics and antecedent conditions. Isotope time series from precipitation, streams and catchment source waters (overland flow and hillslope drainage) were also generated. These allowed us to model the non-stationary characteristics of their ages. Stream water age ranges from 3 months at high flows when overland flow dominates runoff to 4 yrs under baseflow. Overland flow age was a dominant influence on DOC transport. Highest concentrations occurred in small summer events with relatively young (management strategies.

  11. A new time-space accounting scheme to predict stream water residence time and hydrograph source components at the watershed scale

    Science.gov (United States)

    Takahiro Sayama; Jeffrey J. McDonnell

    2009-01-01

    Hydrograph source components and stream water residence time are fundamental behavioral descriptors of watersheds but, as yet, are poorly represented in most rainfall-runoff models. We present a new time-space accounting scheme (T-SAS) to simulate the pre-event and event water fractions, mean residence time, and spatial source of streamflow at the watershed scale. We...

  12. Predictive analyses of ground-water discharges in the Willow Creek Watershed, northeast Nebraska

    Science.gov (United States)

    Dugan, Jack T.; Lappala, E.G.

    1978-01-01

    Ground-water discharge to Willow Creek in northeast Nebraska was predicted with a digital model of the ground-water/surface-water system. Recharge and irrigation requirements were determined with a model of the soil zone. The regional aquifer is Pliocene and Pleistocene sands and gravels. Water in the regional aquifer is unconfined in the western part of the watershed and confined in the eastern part. The confining layer is Pleistocene eolian silts with very fine sand interbeds overlying a basal clay. Where the regional aquifer is unconfined, perennial flow of Willow Creek is sustained by ground-water discharge. Where it is confined, the low hydraulic conductivity of the confining beds isolates the regional aquifer from Willow Creek. Adequate agreement between simulated and observed streamflows and water levels during 1975 and 1976 was obtained by modifying initial estimates of hydraulic conductivity and specific storage. The future perennial flow of Willow Creek was simulated by superimposing six patterns of ground-water withdrawals upon variations in recharge for a monthly climatic sequence identical with the period 1931-34. These analyses showed that the perennial monthly flows would be less than 12 cubic feet per second at least 50 percent of the time. (Woodard-USGS)

  13. Companion Modeling, Conflict Resolution, and Institution Building: Sharing Irrigation Water in the Lingmuteychu Watershed, Bhutan

    Directory of Open Access Journals (Sweden)

    Tayan Raj. Gurung

    2006-12-01

    Full Text Available We used multi-agent systems (MAS, following the companion modeling method, to facilitate water management negotiations in Bhutan. We show how this methodology helped resolve a conflict over the sharing of water resources by establishing a concrete agreement and creating an institution for collective watershed management. The conceptual model begins with a role-playing game (RPG. The stakeholders play the game, thus validating the proposed environment, the behavioral rules, and the emergent properties of the game. It is then relatively easy to translate the RPG into computerized MAS that allow different scenarios to be explored. After this first step in the MAS model, stakeholders then create an institution. A second model is developed to facilitate this process. We conclude by discussing the relationship between the models and reality, as well as the use of MAS as a mediation tool and the social process.

  14. Sediment–water distribution of contaminants of emerging concern in a mixed use watershed

    Energy Technology Data Exchange (ETDEWEB)

    Fairbairn, David J., E-mail: david.fairbairn@state.mn.us [University of Minnesota, Water Resources Center, 1985 Buford Ave., St Paul, MN 55108 (United States); Karpuzcu, M. Ekrem [University of Minnesota, Water Resources Center, 1985 Buford Ave., St Paul, MN 55108 (United States); Arnold, William A. [University of Minnesota, Civil, Environmental, and Geo-Engineering, 500 Pillsbury Drive SE, Minneapolis, MN 55455 (United States); Barber, Brian L. [University of Minnesota, Department of Soil, Water, and Climate, 1902 Dudley Ave, Saint Paul, MN 55108 (United States); Kaufenberg, Elizabeth F. [University of Minnesota, Water Resources Center, 1985 Buford Ave., St Paul, MN 55108 (United States); Koskinen, William C. [United States Department of Agriculture, Agricultural Research Service, 1991 Upper Buford Circle, University of Minnesota, Saint Paul, MN 55108 (United States); Novak, Paige J. [University of Minnesota, Civil, Environmental, and Geo-Engineering, 500 Pillsbury Drive SE, Minneapolis, MN 55455 (United States); Rice, Pamela J. [United States Department of Agriculture, Agricultural Research Service, 1991 Upper Buford Circle, University of Minnesota, Saint Paul, MN 55108 (United States); Swackhamer, Deborah L. [University of Minnesota, Water Resources Center, 1985 Buford Ave., St Paul, MN 55108 (United States)

    2015-02-01

    This study evaluated the occurrence and distribution of 15 contaminants of emerging concern (CECs) in stream water and sediments in the Zumbro River watershed in Minnesota and compared these with sub-watershed land uses. Sixty pairs of sediment and water samples were collected across all seasons from four stream sites for over two years and analyzed for selected personal care products, pesticides, human and veterinary medications, and phytoestrogens. Spatial and temporal analyses indicate that pharmaceuticals and personal care products (urban/residential CECs) are significantly elevated in water and/or sediment at sites with greater population density (> 100 people/km{sup 2}) and percentage of developed land use (> 8% of subwatershed area) than those with less population density and land area under development. Significant spatial variations of agricultural pesticides in water and sediment were detectable, even though all sites had a high percentage of agricultural land use. Seasonality in CEC concentration was observed in water but not in sediment, although sediment concentrations of three CECs did vary between years. Average measured non-equilibrium distribution coefficients exceeded equilibrium hydrophobic partitioning-based predictions for 5 of the 7 detected CECs by at least an order of magnitude. Agreement of measured and predicted distribution coefficients improved with increasing hydrophobicity and in-stream persistence. The more polar and degradable CECs showed greater variability in measured distributions across different sampling events. Our results confirm that CECs are present in urban and agricultural stream sediments, including those CECs that would typically be thought of as non-sorptive based on their log K{sub ow} values. These results and the observed patterns of sediment and water distributions augment existing information to improve prediction of CEC fate and transport, leading to more accurate assessments of exposure and risk to surface water

  15. Water quality monitoring of the Pirapó River watershed, Paraná, Brazil

    Directory of Open Access Journals (Sweden)

    E. C. Bortoletto

    Full Text Available This study aimed to evaluate the water quality of the Pirapó River watershed in Paraná, Brazil, and identify the critical pollution sites throughout the drainage basin. The water quality was monitored during the period from January 2011 to December 2012. Nine points distributed throughout the main channel of the Pirapó River were sampled for a total of 17 samplings. The water quality was evaluated based on the determination of 14 physical, chemical and microbiological parameters. Analysis of the variables monitored in the Pirapó River watershed using factor analysis/principal components analysis (FA/PCA indicated the formation of three distinct groups of parameters: water temperature (Twater, dissolved oxygen (DO and a group composed of total suspended solids (TSS, turbidity and nitrite (NO2–. The parameters Twater and DO exhibited a relationship with the seasonality, and the TSS, turbidity, and NO2– levels were correlated with surface runoff caused by rainfall events. Principal component analysis (PCA of the sampling points enabled the selection of the 10 most important variables from among the 14 evaluated parameters. The results showed that the nitrate (NO3–, NO2–, TSS, turbidity and total phosphorous (TP levels were related to the soil type, and the parameters DO, electrical conductivity (EC, ammoniacal nitrogen (N-NH3 and thermotolerant coliforms (TC were related to organic matter pollution, with the P5 sampling site being the most critical site. The ordination diagram of the sampling points as a function of the PCA indicated a reduction from 9 to 5 sampling points, indicating the potential for decreasing the costs associated with monitoring.

  16. Potential effects of climate change and variability on watershed biogeochemical processes and water quality in Northeast Asia.

    Science.gov (United States)

    Park, Ji-Hyung; Duan, Lei; Kim, Bomchul; Mitchell, Myron J; Shibata, Hideaki

    2010-02-01

    An overview is provided of the potential effects of climate change on the watershed biogeochemical processes and surface water quality in mountainous watersheds of Northeast (NE) Asia that provide drinking water supplies for large populations. We address major 'local' issues with the case studies conducted at three watersheds along a latitudinal gradient going from northern Japan through the central Korean Peninsula and ending in southern China. Winter snow regimes and ground snowpack dynamics play a crucial role in many ecological and biogeochemical processes in the mountainous watersheds across northern Japan. A warmer winter with less snowfall, as has been projected for northern Japan, will alter the accumulation and melting of snowpacks and affect hydro-biogeochemical processes linking soil processes to surface water quality. Soils on steep hillslopes and rich in base cations have been shown to have distinct patterns in buffering acidic inputs during snowmelt. Alteration of soil microbial processes in response to more frequent freeze-thaw cycles under thinner snowpacks may increase nutrient leaching to stream waters. The amount and intensity of summer monsoon rainfalls have been increasing in Korea over recent decades. More frequent extreme rainfall events have resulted in large watershed export of sediments and nutrients from agricultural lands on steep hillslopes converted from forests. Surface water siltation caused by terrestrial export of sediments from these steep hillslopes is emerging as a new challenge for water quality management due to detrimental effects on water quality. Climatic predictions in upcoming decades for southern China include lower precipitation with large year-to-year variations. The results from a four-year intensive study at a forested watershed in Chongquing province showed that acidity and the concentrations of sulfate and nitrate in soil and surface waters were generally lower in the years with lower precipitation, suggesting year

  17. Minimum forest cover required for sustainable water flow regulation of a watershed: a case study in Jambi Province, Indonesia

    Directory of Open Access Journals (Sweden)

    S. Tarigan

    2018-01-01

    Full Text Available In many tropical regions, the rapid expansion of monoculture plantations has led to a sharp decline in forest cover, potentially degrading the ability of watersheds to regulate water flow. Therefore, regional planners need to determine the minimum proportion of forest cover that is required to support adequate ecosystem services in these watersheds. However, to date, there has been little research on this issue, particularly in tropical areas where monoculture plantations are expanding at an alarming rate. Therefore, in this study, we investigated the influence of forest cover and oil palm (Elaeis guineensis and rubber (Hevea brasiliensis plantations on the partitioning of rainfall into direct runoff and subsurface flow in a humid, tropical watershed in Jambi Province, Indonesia. To do this, we simulated streamflow with a calibrated Soil and Water Assessment Tool (SWAT model and observed several watersheds to derive the direct runoff coefficient (C and baseflow index (BFI. The model had a strong performance, with Nash–Sutcliffe efficiency values of 0.80–0.88 (calibration and 0.80–0.85 (validation and percent bias values of −2.9–1.2 (calibration and 7.0–11.9 (validation. We found that the percentage of forest cover in a watershed was significantly negatively correlated with C and significantly positively correlated with BFI, whereas the rubber and oil palm plantation cover showed the opposite pattern. Our findings also suggested that at least 30 % of the forest cover was required in the study area for sustainable ecosystem services. This study provides new adjusted crop parameter values for monoculture plantations, particularly those that control surface runoff and baseflow processes, and it also describes the quantitative association between forest cover and flow indicators in a watershed, which will help regional planners in determining the minimum proportion of forest and the maximum proportion of plantation to ensure that a

  18. Water and sediment study of the Snake River watershed, Colorado, Oct. 9-12, 2001

    Science.gov (United States)

    Fey, D.L.; Church, S.E.; Unruh, D.M.; Bove, D.J.

    2002-01-01

    The Snake River watershed, located upstream from Dillon Reservoir in the central mountains of Colorado, has been affected by historical base-metal mining. Trout stocked in the Snake River for recreational purposes do not survive through the winter. Sediment cores analyzed by previous investigators from the reservoir revealed elevated concentrations of base metals and mercury. We collected 36 surface water samples (filtered and unfiltered) and 38 streambed-sediment samples from streams in the Snake River watershed. Analyses of the sediment and water samples show that concentrations of several metals exceed aquatic life standards in one or both media. Ribbon maps showing dissolved concentrations of zinc, cadmium, copper, and manganese in water (0.45-micron filtered and corrected for the ameliorating effect of hardness), and copper, cadmium, and zinc in sediment indicate reaches where toxic effects on trout would be expected and stream reaches where toxicity standards for rainbow, brown, and brook trout are exceeded. Instantaneous loads for sulfate, strontium, iron, cadmium, copper, and zinc were calculated from 0.45-micron-filtered water concentrations and discharge measurements were made at each site. Sulfate and strontium behave conservatively, whereas copper, cadmium, and zinc are reactive. The dissolved copper load entering the reservoir is less than 20 percent of the value calculated from some upper reaches; copper is transferred to suspended and or streambed sediment by sorption to iron oxyhydroxides. Higher percentages of zinc and cadmium reach the reservoir in dissolved form; however, load calculations indicate that some of these metals are also precipitated out of solution. The most effective remediation activities should be concentrated on reducing the dissolved loads of zinc, cadmium, and copper in two reaches of lower Peru Creek between the confluence with the Snake River and Cinnamon Gulch. We analyzed all streambed sediment for mercury and selected

  19. High Resolution Modeling of Climate Change Impacts on Water Supply and Demand, and GHG Emissions, Similkameen Watershed, BC, Canada

    Science.gov (United States)

    Mirmasoudi, S.; Byrne, J. M.; Chasmer, L.; Kroebel, R.; Johnson, D. L.; MacDonald, R. J.

    2016-12-01

    In western North America, water supply is largely derived from mountain snowmelt. Climate change will have a significant impact on mountain snowpack and subsequently, the snow-derived water supply. This will strain water supplies and increase water demand in areas with substantial irrigation agriculture. This work will address a series of objectives based on a range of future climate scenarios in the Similkameen watershed, BC, Canada. First, to improve GIS-based radiation estimation by modelling local atmospheric transmissivity and diffusion functions. Second, to model historical and future water supplies under a range of climate scenarios using the Generate Earth Systems Science (GENESYS) model. Third, to assess climate driven changes in water requirement and associated crop productivity for a range of future climate scenarios using the GENESYS. Fourth, to link the GENESYS and the Holos model to estimate farm and regional level GHG emissions for the crops and land covers in the watershed.

  20. The occurrence of antibiotics in an urban watershed: From wastewater to drinking water

    Science.gov (United States)

    Watkinson, A.J.; Murby, E.J.; Kolpin, D.W.; Costanzo, S.D.

    2009-01-01

    The presence of 28 antibiotics in three hospital effluents, five wastewater treatment plants (WWTPs), six rivers and a drinking water storage catchment were investigated within watersheds of South–East Queensland, Australia. All antibiotics were detected at least once, with the exception of the polypeptide bacitracin which was not detected at all. Antibiotics were found in hospital effluent ranging from 0.01–14.5 μg L-1, dominated by the β-lactam, quinolone and sulphonamide groups. Antibiotics were found in WWTP influent up to 64 μg L-1, dominated by the β-lactam, quinolone and sulphonamide groups. Investigated WWTPs were highly effective in removing antibiotics from the water phase, with an average removal rate of greater than 80% for all targeted antibiotics. However, antibiotics were still detected in WWTP effluents in the low ng L-1 range up to a maximum of 3.4 μg L-1, with the macrolide, quinolone and sulphonamide antibiotics most prevalent. Similarly, antibiotics were detected quite frequently in the low ng L-1 range, up to 2 μg L-1 in the surface waters of six investigated rivers including freshwater, estuarine and marine samples. The total investigated antibiotic concentration (TIAC) within the Nerang River was significantly lower (p p antibiotics to streams. Despite the presence of antibiotics in surface waters used for drinking water extraction, no targeted antibiotics were detected in any drinking water samples.

  1. Snowmelt and rain in a marginal snowpack watershed: Amount and duration of water input controls runoff

    Science.gov (United States)

    Anderson, S. P.; Rock, N.

    2013-12-01

    Snowmelt predictably delivers a concentrated pulse of water to watersheds, and therefore structures ecosystems and human water management. The deep irrigation from snowmelt also delivers water effectively to the base of the critical zone in water-limited climates, and hence controls the advance of the weathering front. Changes in snowmelt therefore stand as a prominent concern for the impacts of future climate warming. We use a headwater watershed in the Colorado Front Range to explore the impacts of varying delivery of rain and snow on runoff. Gordon Gulch, a 2.7 km2 forested watershed at 2650 m elevation in the Colorado Front Range, is drained by a small first order stream. A snowpack builds on north-facing slopes, while snow comes and goes on south-facing slopes. In water years 2010-2012, total precipitation ranged from 480 to 560 mm. Total runoff, which ranged from 55 to 102 mm, does not correlate with annual precipitation. Over half of the total annual discharge occurs in a period of a few weeks each year; in two of the study years, peak discharge occurred in spring following snowmelt. In one year, peak discharge was entirely rain driven. In 2010 and 2011, discharge peaked during late spring (May) storms after the snow pack melted. The highest annual runoff, and longest duration high discharge period, occurred in water year 2010. In that year, ablation of most of a ~70 cm snowpack (on N-facing slopes; S facing slopes were bare) was followed by a 25 day stormy period in which ~130 mm of mixed rain and snow fell. Two discharge maxima occurred in response to precipitation events during this wet, post-snowpack period. In total, discharge remained high for ~6 weeks. In water year 2011, a smaller snowpack (max. ~30 cm), and drier spring produced a much more compact high runoff season of ~2 weeks. Although water year 2011 had ~10% more total precipitation, it produced 30% less runoff than water year 2010. A greater proportion of the 2011 precipitation fell in summer

  2. Water Resources and Groundwater in a Glaciated Andean Watershed (Cordillera Blanca, Peru)

    Science.gov (United States)

    McKenzie, J. M.; Gordon, R.; Baraer, M.; Lautz, L.; Mark, B. G.; Wigmore, O.; Chavez, D.; Aubry-Wake, C.

    2014-12-01

    It is estimated that almost 400 million people live in watersheds where glaciers provide at least 10% of the runoff, yet many questions remain regarding the impact of climate change and glacier recession on water resources derived from these high mountain watersheds. We present research from the Cordillera Blanca, Peru, an area with the highest density of glaciers in the tropics. While glacier meltwater buffers stream discharge throughout the range, groundwater is a major component of dry season runoff, contributing up to 50-70% of outflow in some tributaries. In order to predict future changes to water resources it is critical to understand how groundwater can offset future hydrologic stress by maintaining stream baseflow, including recharge mechanisms, subsurface pathways, storage, and net fluxes to rivers. We present a synthesis of results based on hydrologic modeling, drilling/piezometers, geophysics, and artificial and natural hydrologic tracers. Our findings show that 'pampas', low-relief mountain valleys, are critical for baseflow generation by storing groundwater on interannual timescales. Pampas have a total area of ~65 km2 and are comprised of unconsolidated glacial, talus, lacustrine and wetland (bofedales) deposits. The valleys commonly have buried talus aquifers that are overlain by low permeability, glaciolacustrine deposits. Glaciofluvial outwash deposits and small wetlands also act as unconfined aquifers. These groundwater systems appear to be primarily recharged by wet season precipitation, and at higher elevations also by glacial meltwater. Additionally a ubiquitous feature in the valleys are springs, often located at the base of talus deposits, which generate a large hydrologic flux within the hydrologic systems. While glaciers are the most visible and vulnerable component of the Andean waterscape, we argue that it is crucial to understand the complete mountain hydrologic cycle, including groundwater, in order to understand the ongoing

  3. Whither the Rangeland?: Protection and conversion in California's Rangeland ecosystems.

    Directory of Open Access Journals (Sweden)

    D Richard Cameron

    Full Text Available Land use change in rangeland ecosystems is pervasive throughout the western United States with widespread ecological, social and economic implications. In California, rangeland habitats have high biodiversity value, provide significant habitat connectivity and form the foundation for a number of ecosystem services. To comprehensively assess the conservation status of these habitats, we analyzed the extent and drivers of habitat loss and the degree of protection against future loss across a 13.5 M ha study area in California. We analyzed rangeland conversion between 1984 and 2008 using time series GIS data and classified resulting land uses with aerial imagery. In total, over 195,000 hectares of rangeland habitats were converted during this period. The majority of conversions were to residential and associated commercial development (49% of the area converted, but agricultural intensification was surprisingly extensive and diverse (40% across six categories. Voluntary enrollment in an agricultural tax incentive program provided widespread protection from residential and commercial conversions across 37% of the remaining rangeland habitat extent (7.5 M ha, though this program did not protect rangeland from conversion to more intensive agricultural uses. Additionally, 24% of the remaining rangeland was protected by private conservation organizations or public agencies through land or easement ownership while 38% had no protection status at all. By developing a spatial method to analyze the drivers of loss and patterns of protection, this study demonstrates a novel approach to prioritize conservation strategies and implementation locations to avert habitat conversion. We propose that this approach can be used in other ecosystem types, and can serve as a regional conservation baseline assessment to focus strategies to effect widespread, cost-effective conservation solutions.

  4. High Nitrogen Fertilization of Tobacco Crop in Headwater Watershed Contaminates Subsurface and Well Waters with Nitrate

    Directory of Open Access Journals (Sweden)

    D. R. Kaiser

    2015-01-01

    Full Text Available Our hypothesis was that subsurface and well waters in watershed with shallow, stony soils, steep landscapes, and cropped to tobacco are contaminated by nitrate. Nitrate in soil solution was monitored in (0.20 m and below (0.5 m root zone with tension lysimeters, in five transects. Water from two wells (beneath tobacco field and in native forest used for human consumption was also analyzed for nitrate. Soil bulk density, porosity, and saturated hydraulic conductivity were evaluated. Soil physical and hydrological properties showed great variation at different landscape positions and soil depths. Soil coarse grain size, high porosity, and saturated hydraulic conductivity favored leaching nitrate. Nitrate in soil solution from tobacco fields was greater than in natural environment. Nitrate reached depths bellow rooting zone with values as high as 80 mg L−1 in tobacco plantation. Water well located below tobacco plantation had high nitrate concentration, sometimes above the critical limit of 10 mg L−1. Tobacco cropping causes significant water pollution by nitrate, posing risk to human health. A large amount of nitrogen fertilizers applied to tobacco and nitrate in subsurface waters demonstrate the unsustainability of tobacco production in small farming units on steeps slopes, with stony and shallow soils.

  5. Fertilizer management in watersheds of two Ramsar wetlands and effects on quality of inflowing water.

    Science.gov (United States)

    Tsiouris, S E; Mamolos, A P; Kalburtji, K L

    2002-05-01

    Two field experiments were carried out in the watersheds of two Ramsar wetland areas, Lakes Koronia and Volvi (area A) and Lakes Mikri and Megali Prespa (area B), to study the effect of application of N fertilizer on wheat yields, the quality of runoff water, and the quality of stream water. The treatments were a combination of two methods of fertilizer application (total amount in fall, and 2/3 in fall + 1/3 in spring) at three rates (0, 100, and 200 kg N/ha) with four replications. Concentrations of NH4+, NO3-, NO2-, P, and Cl- and pH were determined in all water samples. Runoff water quality was not influenced by fertilizer application in either area. Chemical parameters for water did not differ along the selected watercourses in area B, while in area A they were higher in the samples taken near Lake Koronia than in the samples taken upstream, indicating that the watercourses are polluted downstream by nonagricultural sources. The differences in wheat yields between the 100 and 200 kg N/ha application rates were not high. These results call for better fertilizer management in order to achieve better yields and to diminish the possibility to have negative effects to the environment.

  6. Human health risk assessment of dissolved metals in groundwater and surface waters in the Melen watershed, Turkey.

    Science.gov (United States)

    Çelebi, Ahmet; Sengörür, Bülent; Kløve, Bjørn

    2014-01-01

    Determination of metal risk levels in potable water and their effects on human health are vital in assessment of water resources. Risk assessment of metals to human health in a watershed, which has not been studied before, is the main objective of the present study. Surface and groundwater sampling was carried out between September 2010 and August 2011 in the Melen Watershed, Turkey, an important drinking water resource for millions of people. Metals were analyzed in the laboratory using inductively coupled plasma. Of the 26 different metals monitored, Al, B, Ba, Cr, Cu, Fe, Mn, Mo and V were found in surface water and As, B, Ba, Cr, Cu, Mn, Mo, V and Zn in groundwater. In groundwater, unitless hazard quotient (HQ) values were 6 for As, 2.7 for Mn and 1 for Zn, while in surface water all metals were below the risk level (HQ health and that potential carcinogenic impacts should receive more attention.

  7. Geology, Hydrology, and Water Quality of the Little Blackwater River Watershed, Dorchester County, Maryland, 2006-09

    Science.gov (United States)

    Fleming, Brandon J.; DeJong, Benjamin D.; Phelan, Daniel J.

    2011-01-01

    The Little Blackwater River watershed is a low-lying tidal watershed in Dorchester County, Maryland. The potential exists for increased residential development in a mostly agricultural watershed that drains into the Blackwater National Wildlife Refuge. Groundwater and surface-water levels were collected along with water-quality samples to document hydrologic and geochemical conditions within the watershed prior to potential land-use changes. Lithologic logs were collected in the Little Blackwater River watershed and interpreted with existing geophysical logs to conceptualize the shallow groundwater-flow system. A shallow water table exists in much of the watershed as shown by sediment cores and surface geophysical surveys. Water-table wells have seasonal variations of 6 feet, with the lowest water levels occurring in September and October. Seasonally low water-table levels are lower than the stage of the Little Blackwater River, creating the potential for surface-water infiltration into the water table. Two stream gages, each equipped with stage, velocity, specific conductance, and temperature sensors, were installed at the approximate mid-point of the watershed and near the mouth of the Little Blackwater River. The gages recorded data continuously and also were equipped with telemetry. Discharge calculated at the mouth of the Little Blackwater River showed a seasonal pattern, with net positive discharge in the winter and spring months and net negative discharge (flow into the watershed from Blackwater National Wildlife Refuge and Fishing Bay) in the summer and fall months. Continuous water-quality records showed an increase in specific conductance during the summer and fall months. Discrete water-quality samples were collected during 2007--08 from 13 of 15 monitoring wells and during 2006--09 from 9 surface-water sites to characterize pre-development conditions and the seasonal variability of inorganic constituents and nutrients. The highest mean values of

  8. Watershed features and stream water quality: Gaining insight through path analysis in a Midwest urban landscape, USA

    Science.gov (United States)

    Jiayu Wu; Timothy W. Stewart; Janette R. Thompson; Randy Kolka; Kristie J. Franz

    2015-01-01

    Urban stream condition is often degraded by human activities in the surrounding watershed. Given the complexity of urban areas, relationships among variables that cause stream degradation can be difficult to isolate. We examined factors affecting stream condition by evaluating social, terrestrial, stream hydrology and water quality variables from 20 urban stream...

  9. Development of EOS-aided procedures for the determination of the water balance of hydrologic budget of a large watershed

    Science.gov (United States)

    Congalton, Russell G.; Thomas, Randall W.; Zinke, Paul J.

    1986-01-01

    Work focused on the acquisition of remotely sensed data for the 1985 to 1986 hydrogolic year; continuation of the field measurement program; continued acquisition and construction of passive microwave remote sensing instruments; a compilation of data necessary for an initial water balance computation; and participation with the EOS Simulataneity Team in reviewing the Feather River watershed as a possible site for a simultaneity experiment.

  10. Water and nonpoint source pollution estimation in the watershed with limited data availability based on hydrological simulation and regression model.

    Science.gov (United States)

    Huiliang, Wang; Zening, Wu; Caihong, Hu; Xinzhong, Du

    2015-09-01

    Nonpoint source (NPS) pollution is considered as the main reason for water quality deterioration; thus, to quantify the NPS loads reliably is the key to implement watershed management practices. In this study, water quality and NPS loads from a watershed with limited data availability were studied in a mountainous area in China. Instantaneous water discharge was measured through the velocity-area method, and samples were taken for water quality analysis in both flood and nonflood days in 2010. The streamflow simulated by Hydrological Simulation Program-Fortran (HSPF) from 1995 to 2013 and a regression model were used to estimate total annual loads of various water quality parameters. The concentrations of total phosphorus (TP) and total nitrogen (TN) were much higher during the flood seasons, but the concentrations of ammonia nitrogen (NH3-N) and nitrate nitrogen (NO3-N) were lower during the flood seasons. Nevertheless, only TP concentration was positively correlated with the flow rate. The fluctuation of annual load from this watershed was significant. Statistical results indicated the significant contribution of pollutant fluxes during flood seasons to annual fluxes. The loads of TP, TN, NH3-N, and NO3-N in the flood seasons were accounted for 58-85, 60-82, 63-88, 64-81% of the total annual loads, respectively. This study presented a new method for estimation of the water and NPS loads in the watershed with limited data availability, which simplified data collection to watershed model and overcame the scale problem of field experiment method.

  11. The Role of Structure and Stratigraphy on Surface-Water Interactions in a Gaining Reach of the EL Rito Watershed

    Science.gov (United States)

    Stewart-Maddox, N. S.; Degon, A.; Tysor, E.; Swanson, J.; Howard, J.; Frisbee, M. D.; Wilson, J. L.; Newman, B. D.

    2014-12-01

    Understanding the interactions between groundwater and surface water is critical to the future sustainability of communities in semi-arid watersheds. Streamflow is the primary source of water for acequias and irrigation in many semi-arid watersheds and sustained perennial streamflow is thought to depend on greater fractions of deep groundwater following the snowmelt pulse. The persistent perception is that deep groundwater is not a significant component of streamflow generation despite recent observations in the Saguache Creek and Rio Hondo watersheds refuting this perception. Recent research indicates that groundwater/surface water interactions are very complex in the El Rito watershed, a mountainous, sedimentary watershed in northern New Mexico. The El Rito watershed can be broken into four distinct hydrogeological zones: 1) perennial streamflow in the headwaters maintained by springs and groundwater discharge, 2) losing conditions downstream of the headwaters, 3) a small, persistent 500 m gaining stretch in the mid-reach, and 4) losing conditions from the mid-reaches to the outlet. In this poster, we investigate the processes controlling zone 3. We hypothesize that extensional faulting associated with the Rio Grande Rift combined with the westerly dip of stratigraphic units are responsible for the creation of the small gaining reach. We test this hypothesis using high-resolution stream gauging, radon measurements in streams and springs, electrical resistivity surveys, geologic mapping, and temperature logging of streamflow. Our data show that the upwelling occurs near a small east-west trending fault contact characterized by a sharp contrast in water table depth (higher water tables downstream of the fault), persistent and spatially confined temperature anomalies in streamflow associated with the discharge of groundwater. These data provide support for the hypothesis and indicate that structural geologic and stratigraphic features may have profound effects on

  12. The Han River watershed management initiative for the South-to-North Water Transfer project (Middle Route) of China.

    Science.gov (United States)

    Zhang, Quanfa; Xu, Zhifang; Shen, Zehao; Li, Siyue; Wang, Shusen

    2009-01-01

    The South-to-North Water Transfer (SNWT) Project of China is the largest of its kind ever implemented. Of its three routes (i.e., East, Middle and West), the middle one will transfer 14 billion m(3) of water annually from the Han River, a tributary of the Yangtze and the water supplying area, to Beijing by 2030. Thus water quality in the 95,000 km(2) upper Han River basin is of great concern. A watershed management initiative has been implemented in the basin, and the ultimate objectives are to quantify basin's ecosystem functioning and to develop an integrated management system with respect to water resources conservation. Specifically, the program includes five activities: characterization of riparian ecosystems, detection of land use and land cover change, quantification of nutrient cycling of representative ecosystems, determination of spatial and temporal variations of water quality, and finally development of a watershed management system for water conservation. This article provides the justifications of the watershed management initiative and the initial results are comprehended with respect to the water conservation in the Han River basin.

  13. TOPMODEL simulations of streamflow and depth to water table in Fishing Brook Watershed, New York, 2007-09

    Science.gov (United States)

    Nystrom, Elizabeth A.; Burns, Douglas A.

    2011-01-01

    TOPMODEL, a physically based, variable-source area rainfall-runoff model, was used to simulate streamflow and depth to water table for the period January 2007-September 2009 in the 65.6 square kilometers of Fishing Brook Watershed in northern New York. The Fishing Brook Watershed is located in the headwaters of the Hudson River and is predominantly forested with a humid, cool continental climate. The motivation for applying this model at Fishing Brook was to provide a simulation that would be effective later at this site in modeling the interaction of hydrologic processes with mercury dynamics.

  14. Climate impacts on agriculture: Implications for forage and rangeland production

    Energy Technology Data Exchange (ETDEWEB)

    Izaurralde, Roberto C.; Thomson, Allison M.; Morgan, Jack; Fay, Philip; Polley, Wayne; Hatfield, Jerry L.

    2011-04-19

    Projections of temperature and precipitation patterns across the United States during the next 50 years anticipate a 1.5 to 2°C warming and a slight increase in precipitation as a result of global climate change. There have been relatively few studies of climate change impacts on pasture and rangeland (grazingland) species compared to those on crop species, despite the economic and ecological importance of the former. Here we review the literature on pastureland and rangeland species to rising CO2 and climate change (temperature, and precipitation) and discuss plant and management factors likely to influence pastureland and rangeland responses to change (e.g., community composition, plant competition, perennial growth habit, seasonal productivity, and management methods). Overall, the response of pasture species to increased [CO2] is consistent with the general response of C3 and C4 type vegetation, although significant exceptions exist. Both pastureland and rangeland species should exhibit an acceleration of metabolism and development due to earlier onset of spring green-up and longer growing seasons. However, in the studies reviewed here, C3 pasture species increased their photosynthetic rates by up to 40% while C4 species exhibited no increase in photosynthesis. In general, it is expected that increases in [CO2] and precipitation would enhance rangeland net primary production (NPP) while increased air temperatures would either increase or decrease NPP. Much of this uncertainty in response is due to uncertain future projections of precipitation, both globally and regionally. For example, if annual precipitation changes little or declines, rangeland plant response to warming temperatures and rising [CO2] may be neutral or may decline due to increased water stress. This review reveals the need for comprehensive studies of climate change impacts on the pasture ecosystem including grazing regimes, mutualistic relationships (e.g., plant roots-nematodes; N

  15. Evaluating the impact of irrigation on surface water – groundwater interaction and stream temperature in an agricultural watershed

    Science.gov (United States)

    Essaid, Hedeff I.; Caldwell, Rodney R.

    2017-01-01

    Changes in groundwater discharge to streams caused by irrigation practices can influence stream temperature. Observations along two currently flood-irrigated reaches in the 640-square-kilometer upper Smith River watershed, an important agricultural and recreational fishing area in west-central Montana, showed a downstream temperature decrease resulting from groundwater discharge to the stream. A watershed-scale coupled surface water and groundwater flow model was used to examine changes in streamflow, groundwater discharge to the stream and stream temperature resulting from irrigation practices. The upper Smith River watershed was used to develop the model framework including watershed climate, topography, hydrography, vegetation, soil properties and current irrigation practices. Model results were used to compare watershed streamflow, groundwater recharge, and groundwater discharge to the stream for three scenarios: natural, pre-irrigation conditions (PreIrr); current irrigation practices involving mainly stream diversion for flood and sprinkler irrigation (IrrCurrent); and a hypothetical scenario with only groundwater supplying sprinkler irrigation (IrrGW). Irrigation increased groundwater recharge relative to natural PreIrr conditions because not all applied water was removed by crop evapotranspiration. Groundwater storage and groundwater discharge to the stream increased relative to natural PreIrr conditions when the source of irrigation water was mainly stream diversion as in the IrrCurrent scenario. The hypothetical IrrGW scenario, in which groundwater withdrawals were the sole source of irrigation water, resulted in widespread lowering of the water table and associated decreases in groundwater storage and groundwater discharge to the stream. A mixing analysis using model predicted groundwater discharge along the reaches suggests that stream diversion and flood irrigation, represented in the IrrCurrent scenario, has led to cooling of stream temperatures

  16. Impact of Rangeland Degradation on Soil Physical, Chemical

    African Journals Online (AJOL)

    In terms of impacts from soil compaction, Abdel-Megid et al, (1987) reported reduced water infiltration and aeration, while Van der westhuizen et al., (1999) found poor plant respiration and soil seed germination unless the soil crust is broken. Soil compaction also enhanced encroachment in eastern rangelands of Ethiopia ...

  17. Ranch business planning and resource monitoring for rangeland sustainability

    Science.gov (United States)

    Kristie A. Maczko; John A. Tanaka; Michael Smith; Cindy Garretson-Weibel; Stanley F. Hamilton; John E. Mitchell; Gene Fults; Charles Stanley; Dick Loper; Larry D. Bryant; J. K. (Rooter) Brite

    2012-01-01

    Aligning a rancher's business plan goals with the capability of the ranch's rangeland resources improves the viability and sustainability of family ranches. Strategically monitoring the condition of soil, water, vegetation, wildlife, livestock production, and economics helps inform business plan goals. Business planning and resource monitoring help keep...

  18. Vulnerability of amphibians to climate change: implications for rangeland management

    Science.gov (United States)

    Karen E. Bagne; Deborah M. Finch; Megan M. Friggens

    2011-01-01

    Many amphibian populations have declined drastically in recent years due to a large number of factors including the emerging threat of climate change (Wake 2007). Rangelands provide important habitat for amphibians. In addition to natural wetlands, stock tanks and other artificial water catchments provide habitat for many amphibian species (Euliss et al. 2004).

  19. Assessment of water retention function as tool to improve integrated watershed management (case study of Poprad river basin, Slovakia).

    Science.gov (United States)

    Šatalová, Barbora; Kenderessy, Pavol

    2017-12-01

    The presented study concentrates on assessing the ecosystem function of water retention. The water retention function is defined as the ability of the landscape to retain water, slow runoff and encourage water infiltration. The water retention function was expressed by calculating the hydric significance (HS) indicator. This method is based on scoring the individual input parameters according to their overall impact on watershed hydrology. The study was conducted on a sample area of Poprad River basin. The final results presented a spatial distribution of hydric function within the watershed classified according to its significance into four classes (from limited to excellent significance). A breakdown of the results on the level of elementary watersheds was used in order to examine those with low hydric function. The results showed a significant influence of land-use on retention function; however, this impact could be limited by extreme precipitation or high soil water saturation. The methodology of hydric significance represents an innovative approach towards assessment of ecosystem function of water retention on regional level. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Development of total maximum daily loads for bacteria impaired watershed using the comprehensive hydrology and water quality simulation model.

    Science.gov (United States)

    Kim, Sang M; Brannan, Kevin M; Zeckoski, Rebecca W; Benham, Brian L

    2014-01-01

    The objective of this study was to develop bacteria total maximum daily loads (TMDLs) for the Hardware River watershed in the Commonwealth of Virginia, USA. The TMDL program is an integrated watershed management approach required by the Clean Water Act. The TMDLs were developed to meet Virginia's water quality standard for bacteria at the time, which stated that the calendar-month geometric mean concentration of Escherichia coli should not exceed 126 cfu/100 mL, and that no single sample should exceed a concentration of 235 cfu/100 mL. The bacteria impairment TMDLs were developed using the Hydrological Simulation Program-FORTRAN (HSPF). The hydrology and water quality components of HSPF were calibrated and validated using data from the Hardware River watershed to ensure that the model adequately simulated runoff and bacteria concentrations. The calibrated and validated HSPF model was used to estimate the contributions from the various bacteria sources in the Hardware River watershed to the in-stream concentration. Bacteria loads were estimated through an extensive source characterization process. Simulation results for existing conditions indicated that the majority of the bacteria came from livestock and wildlife direct deposits and pervious lands. Different source reduction scenarios were evaluated to identify scenarios that meet both the geometric mean and single sample maximum E. coli criteria with zero violations. The resulting scenarios required extreme and impractical reductions from livestock and wildlife sources. Results from studies similar to this across Virginia partially contributed to a reconsideration of the standard's applicability to TMDL development.

  1. Spatial and temporal relationships among watershed mining, water quality, and freshwater mussel status in an eastern USA river.

    Science.gov (United States)

    Zipper, Carl E; Donovan, Patricia F; Jones, Jess W; Li, Jing; Price, Jennifer E; Stewart, Roger E

    2016-01-15

    The Powell River of southwestern Virginia and northeastern Tennessee, USA, drains a watershed with extensive coal surface mining, and it hosts exceptional biological richness, including at-risk species of freshwater mussels, downstream of mining-disturbed watershed areas. We investigated spatial and temporal patterns of watershed mining disturbance; their relationship to water quality change in the section of the river that connects mining areas to mussel habitat; and relationships of mining-related water constituents to measures of recent and past mussel status. Freshwater mussels in the Powell River have experienced significant declines over the past 3.5 decades. Over that same period, surface coal mining has influenced the watershed. Water-monitoring data collected by state and federal agencies demonstrate that dissolved solids and associated constituents that are commonly influenced by Appalachian mining (specific conductance, pH, hardness and sulfates) have experienced increasing temporal trends from the 1960s through ~2008; but, of those constituents, only dissolved solids concentrations are available widely within the Powell River since ~2008. Dissolved solids concentrations have stabilized in recent years. Dissolved solids, specific conductance, pH, and sulfates also exhibited spatial patterns that are consistent with dilution of mining influence with increasing distance from mined areas. Freshwater mussel status indicators are correlated negatively with dissolved solids concentrations, spatially and temporally, but the direct causal mechanisms responsible for mussel declines remain unknown. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. Effects of impervious area and BMP implementation and design on storm runoff and water quality in eight small watersheds

    Science.gov (United States)

    Aulenbach, Brent T.; Landers, Mark N.; Musser, Jonathan W.; Painter, Jaime A.

    2017-01-01

    The effects of increases in effective impervious area (EIA) and the implementation of water quality protection designed detention pond best management practices (BMPs) on storm runoff and stormwater quality were assessed in Gwinnett County, Georgia, for the period 2001-2008. Trends among eight small watersheds were compared, using a time trend study design. Significant trends were detected in three storm hydrologic metrics and in five water quality constituents that were adjusted for variability in storm characteristics and climate. Trends in EIA ranged from 0.10 to 1.35, and changes in EIA treated by BMPs ranged from 0.19 to 1.32; both expressed in units of percentage of drainage area per year. Trend relations indicated that for every 1% increase in watershed EIA, about 2.6, 1.1, and 1.5% increases in EIA treated by BMPs would be required to counteract the effects of EIA added to the watersheds on peak streamflow, stormwater yield, and storm streamflow runoff, respectively. Relations between trends in EIA, BMP implementation, and water quality were counterintuitive. This may be the result of (1) changes in constituent inputs in the watersheds, especially downstream of areas treated by BMPs; (2) BMPs may have increased the duration of stormflow that results in downstream channel erosion; and/or (3) spurious relationships between increases in EIA, BMP implementation, and constituent inputs with development rates.

  3. Rangelands: Where anthromes meet their limits

    Science.gov (United States)

    Defining rangelands as anthromes enabled Ellis and Ramankutty (2008) to conclude that more than three-quarters of Earth’s land is anthropogenic; without rangelands, this figure would have been less than half. They classified all lands grazed by domestic livestock as rangelands, provided that human p...

  4. A systematic review of US rangeland science

    Science.gov (United States)

    Rangeland science aims to create knowledge to sustain rangeland social-ecological systems over the long term. Range science has made substantial progress on understanding ecological dynamics of rangeland systems and the management practices that sustain them, and these findings have been systematica...

  5. Sustainable rangelands ecosystem goods and services

    Science.gov (United States)

    Kristie Maczko; Lorie Hidinger

    2008-01-01

    The Sustainable Rangelands Roundtable (SRR) recognizes the unique contributions rangeland resources make to the nation's wellbeing. To communicate the importance of these commodity and amenity values, SRR participants developed this primer on rangeland ecosystem goods and services. It summarizes the history of the nation's relationship with and reliance upon...

  6. Landscape-scale modeling of water quality in Lake Superior and Lake Michigan watersheds: How useful are forest-based indicators? Journal of Great Lakes Research

    Science.gov (United States)

    Titus S. Seilheimer; Patrick L. Zimmerman; Kirk M. Stueve; Charles H. Perry

    2013-01-01

    The Great Lakes watersheds have an important influence on the water quality of the nearshore environment, therefore, watershed characteristics can be used to predict what will be observed in the streams. We used novel landscape information describing the forest cover change, along with forest census data and established land cover data to predict total phosphorus and...

  7. Water quality and landscape processes of four watersheds in eastern Puerto Rico

    Science.gov (United States)

    Murphy, Sheila F.; Stallard, Robert F.; Contributions by Buss, Heather L.; Gould, William A.; Larsen, Matthew C.; Liu, Zhigang; Martinuzzi, Sebastian; Pares-Ramos, Isabel K.; White, Arthur F.; Zou, Xiaoming

    2012-01-01

    Humid tropical regions occupy about a quarter of Earth's land surface, yet they contribute a substantially higher fraction of the water, solutes, and sediment discharged to the world's oceans. Nearly half of Earth's population lives in the tropics, and development stresses can potentially harm soil resources, water quality, and water supply and in addition increase landslide and flood hazards. Owing to Puerto Rico's steep topography, low water storage capacity, and dependence on trade-wind precipitation, the island's people, ecosystems, and water supply are vulnerable to extreme weather such as hurricanes, floods, and droughts. Eastern Puerto Rico offers a natural laboratory for separating geologic and land-cover influences from regional- and global-scale influences because of its various bedrock types and the changing land cover surrounding intact, mature forest of the Luquillo Experimental Forest. Accordingly, a multiyear assessment of hydrological and biogeochemical processes was designed to develop an understanding of the effects of these differences on local climate, streamflow, water quality, and ecosystems, and to form the basis for a long-term and event-based program of climate and hydrologic monitoring. Because infrequent, large storms play a major role in this landscape, we focused on high-runoff events, sampling 263 storms, including all major hurricanes from 1991 through 2005. The largest storms have profound geomorphic consequences, such as landslides, debris flows, deep gullying on deforested lands, excavation and suspension of sediment in stream channels, and delivery of a substantial fraction of annual stream sediment load. Large storms sometimes entrain ocean foam and spray causing high concentrations of seasalt-derived constituents in stream waters during the storm. Past deforestation and agricultural activities in the Cayaguás and Canóvanas watersheds accelerated erosion and soil loss, and this material continues to be remobilized during large

  8. Gore Creek watershed, Colorado : assessment of historical and current water quantity, water quality, and aquatic ecology, 1968-98

    Science.gov (United States)

    Wynn, Kirby H.; Bauch, Nancy J.; Driver, Nancy E.

    2001-01-01

    The historical and current (1998) water-quantity, water-quality, and aquatic-ecology conditions in the Gore Creek watershed are described as part of a study by the U.S. Geological Survey, done in cooperation with the Town of Vail, the Eagle River Water and Sanitation District, and the Upper Eagle Regional Water Authority. Interpretation of the available water-quantity, water-quality, and aquatic-ecology data collected by various agencies since 1968 showed that background geology and land use in the watershed influence the water quality and stream biota. Surface-water nutrient concentrations generally increased as water moved downstream through the Town of Vail, but concentrations at the mouth of Gore Creek were typical when compared with national data for urban/undeveloped sites. Nitrate concentrations in Gore Creek were highest just downstream from a wastewater-treatment plant discharge, but concentrations decreased at sites farther downstream because of dilution and nitrogen uptake by algae. Recent total phosphorus concentrations were somewhat elevated when compared to the U.S. Environmental Protection Agency recommended level of 0.10 milligram per liter for control of eutrophication in flowing water. However, total phosphorus concentrations at the mouth of Gore Creek were relatively low when compared to a national study of phosphorus in urban land-use areas. Historically, suspended sediment associated with construction of Interstate 70 in the early 1970's has been of primary concern; however, recent data indicate that streambed aggradation of sediment originating from Interstate 70 traction sanding currently is a greater concern. About 4,000 tons of coarse sand and fine gravel is washed into Black Gore Creek each year following application of traction materials to Interstate 70 during adverse winter driving conditions. Suspended-sediment concentrations were low in Black Gore Creek; however, bedload-transport rates of as much as 4 tons per day have been measured

  9. a deterministic model for predicting water yield from two different watersheds

    Directory of Open Access Journals (Sweden)

    Putu Sudira

    2013-07-01

    The final test of the adequacy of the model lay in a comparison of observed and simulated runoff The comparison showed that the observed and simulated runoff values are not significantly different. This was based on the results obtained from statistical measures to test the model. The model did a better simulation in the smaller watershed (Pogung-Code sub watershed than in the larger one (Pulo-Opak sub watershed.

  10. Baseline requirements can hinder trades in water quality trading programs: Evidence from the Conestoga watershed.

    Science.gov (United States)

    Ghosh, Gaurav; Ribaudo, Marc; Shortle, James

    2011-08-01

    The U.S. Environmental Protection Agency (USEPA) and the U.S. Department of Agriculture (USDA) are promoting point/nonpoint trading as a way of reducing the costs of meeting water quality goals. Farms can create offsets by implementing management practices such as conservation tillage, nutrient management and buffer strips. To be eligible to sell offsets or credits, farmers must first comply with baseline requirements. USEPA guidance recommends that the baseline for nonpoint sources be management practices that are consistent with the water quality goal. A farmer would not be able to create offsets until the minimum practice standards are met. An alternative baseline is those practices being implemented at the time the trading program starts, or when the farmer enters the program. The selection of the baseline affects the efficiency and equity of the trading program. It has major implications for which farmers benefit from trading, the cost of nonpoint source offsets, and ultimately the number of offsets that nonpoint sources can sell to regulated point sources. We use a simple model of the average profit-maximizing dairy farmer operating in the Conestoga watershed in Pennsylvania to evaluate the implications of baseline requirements on the cost and quantity of offsets that can be produced for sale in a water quality trading market, and which farmers benefit most from trading. Published by Elsevier Ltd.

  11. EVALUATION AND MAPPING OF RANGELANDS DEGRADATION USING REMOTELY SENSED DATA

    Directory of Open Access Journals (Sweden)

    Majid Ajorlo

    2005-05-01

    Full Text Available The empirical and scientifically documents prove that misuse of natural resource causes degradation in it. So natural resources conservation is important in approaching sustainable development aims. In current study, Landsat Thematic Mapper images and grazing gradient method have been used to map the extent and degree of rangeland degradation. In during ground-based data measuring, factors such as vegetation cover, litter, plant diversity, bare soil, and stone & gravels were estimated as biophysical indicators of degradation. The next stage, after geometric correction and doing some necessary pre-processing practices on the study area’s images; the best and suitable vegetation index has been selected to map rangeland degradation among the Normalized Difference Vegetation Index (NDVI, Soil Adjusted Vegetation Index (SAVI, and Perpendicular Vegetation Index (PVI. Then using suitable vegetation index and distance parameter was produced the rangelands degradation map. The results of ground-based data analysis reveal that there is a significant relation between increasing distance from critical points and plant diversity and also percentage of litter. Also there is significant relation between vegetation cover percent and distance from village, i.e. the vegetation cover percent increases by increasing distance from villages, while it wasn’t the same around the stock watering points. The result of analysis about bare soil and distance from critical point was the same to vegetation cover changes manner. Also there wasn’t significant relation between stones & gravels index and distance from critical points. The results of image processing show that, NDVI appears to be sensitive to vegetation changes along the grazing gradient and it can be suitable vegetation index to map rangeland degradation. The degradation map shows that there is high degradation around the critical points. These areas need urgent attention for soil conservation. Generally, it

  12. Use of watershed factors to predict consumer surfactant risk, water quality, and habitat quality in the upper Trinity River, Texas.

    Science.gov (United States)

    Atkinson, S F; Johnson, D R; Venables, B J; Slye, J L; Kennedy, J R; Dyer, S D; Price, B B; Ciarlo, M; Stanton, K; Sanderson, H; Nielsen, A

    2009-06-15

    Surfactants are high production volume chemicals that are used in a wide assortment of "down-the-drain" consumer products. Wastewater treatment plants (WWTPs) generally remove 85 to more than 99% of all surfactants from influents, but residual concentrations are discharged into receiving waters via wastewater treatment plant effluents. The Trinity River that flows through the Dallas-Fort Worth metropolitan area, Texas, is an ideal study site for surfactants due to the high ratio of wastewater treatment plant effluent to river flow (>95%) during late summer months, providing an interesting scenario for surfactant loading into the environment. The objective of this project was to determine whether surfactant concentrations, expressed as toxic units, in-stream water quality, and aquatic habitat in the upper Trinity River could be predicted based on easily accessible watershed characteristics. Surface water and pore water samples were collected in late summer 2005 at 11 sites on the Trinity River in and around the Dallas-Fort Worth metropolitan area. Effluents of 4 major waste water treatment plants that discharge effluents into the Trinity River were also sampled. General chemistries and individual surfactant concentrations were determined, and total surfactant toxic units were calculated. GIS models of geospatial, anthropogenic factors (e.g., population density) and natural factors (e.g., soil organic matter) were collected and analyzed according to subwatersheds. Multiple regression analyses using the stepwise maximum R(2) improvement method were performed to develop prediction models of surfactant risk, water quality, and aquatic habitat (dependent variables) using the geospatial parameters (independent variables) that characterized the upper Trinity River watershed. We show that GIS modeling has the potential to be a reliable and inexpensive method of predicting water and habitat quality in the upper Trinity River watershed and perhaps other highly urbanized

  13. Cations and microbial indicators: strong relationships in waters of urban/mixed land use watersheds of Southwest, VA

    Science.gov (United States)

    Steele, M.; Badgley, B.

    2016-12-01

    Background The salinity and composition of salts in freshwater streams, rivers, and waterbodies varies substantially, often impacted by human urban, agricultural, and mining land uses. While extreme fluctuations in salinity have been shown to influence both microbial communities and biogeochemical cycles, the differential effects of specific ion species at low salinity levels is poorly understood. The objective of this study was to examine the relationship between water chemistry and microbial water quality indicators. We collected weekly grab samples from nine sub-watersheds in Southwest Virginia. Samples were measured for standard physical and chemical properties: dissolved oxygen, temperature, specific conductance, pH, calcium, magnesium, potassium, chloride, fluoride, sulfate, nitrogen species, phosphorus, and dissolved organic carbon. In addition, three types of microbial fecal indicators were measured: total coliforms, E. coli, and HF183 (a human specific genomic marker). Results The relationships within and between water chemistry and water quality indicators are complex and frequently co-correlated. Concentrations of traditional biogeochemical elements (N, P, C) were less strongly related to water quality indicators than were Ca, Mg, Na in watersheds. Ca and Mg were strongly correlated with total coliforms, r2 = 0.88 and r2 = 0.86 respectively. While potassium is very strongly related to E. coli (r2 = 0.96). Currently, we cannot reasonably explain these relationships by the land use composition or common sources within the landscape. The human specific fecal indicator was not well correlated with other microbial water quality indicators, and yet found ubiquitously across the developed watersheds and most strongly correlated with sodium concentrations (r2 = 0.84). The results suggest that 1) wastewater via subsurface flowpaths may more broadly impact surface water chemistry and quality than expected, and 2) that cation chemistry may influence the microbial

  14. Post-adoption behaviour of farmers towards soil and water conservation technologies of watershed management in India

    Directory of Open Access Journals (Sweden)

    Gopal Lal Bagdi

    2015-09-01

    Full Text Available The Indian Institute of Soil and Water Conservation (IISWC and its Research Centres have developed many successful model watershed projects in India in the past and implemented many Soil and Water Conservation (SWC technologies for sustainable watershed management. While many evaluation studies were conducted on these projects in the past, there has been no assessment of the post-adoption status of the SWC technologies over a longer period. It was imperative to appraise the behaviour of the farmers with regard to the continuance or discontinuance of the technologies adopted, diffusion or infusion that took place and technological gaps that occurred in due course of time in the post watershed programme. Therefore, it was realized that the post-adoption behaviour of beneficiary farmers who have adopted different soil and water conservation technologies for watershed management projects should be studied in detail. The research study was initiated in 2012 as a core project at Vasad as the lead Centre along with IISWC headquarter Dehradun, and Centres Agra, Bellary, Chandigarh, Datia, Kota & Ooty, with the specific objectives of the study to measure the extent of post-adoption behaviour (continued-adoption, discontinuance, technological gap, diffusion and infusion of farmers towards the adopted SWC technologies of watershed management. In the present study various indices regarding continued adoption, dis-adoption (discontinuance, technological gap, diffusion, infusion regarding soil and water conservation technologies for watershed management were developed for measurement of post-adoption behaviour of farmers. It was revealed that a little less than three-fourth (73% of SWC technologies continued to be adopted and more than one-fourth (27% were discontinued by farmers. Out of the total continue adopted SWC technologies by farmers, a little less than one-fifth (19% of technologies continued to be adopted with a technological gap. More than one

  15. PROMET - Large scale distributed hydrological modelling to study the impact of climate change on the water flows of mountain watersheds

    Science.gov (United States)

    Mauser, Wolfram; Bach, Heike

    2009-10-01

    SummaryClimate change will change availability, quality and allocation of regional water resources. Appropriate modelling tools should therefore be available to realistically describe reactions of watersheds to climate change and to identify efficient and effective adaptation strategies on the regional scale. The paper presents the hydrologic model PROMET (Processes of Radiation, Mass and Energy Transfer), which was developed within the GLOWA-Danube project as part of the decision support system DANUBIA. PROMET covers the coupled water and energy fluxes of large-scale ( A ˜ 100,000 km 2) watersheds. It is fully spatially distributed, raster-based with raster-elements of 1 km 2 area, runs on an hourly time step, strictly conserves mass and energy and is not calibrated using measured discharges. Details on the model concept and the individual model components are given. An application case of PROMET is given for the mountainous Upper-Danube watershed in Central Europe ( A = 77,000 km 2). The water resources are intensively utilized for hydropower, agriculture, industry and tourism. The water flows are significantly influenced by man-made structures like reservoirs and water diversions. A 33-years model run covering the period from 1971 to 2003 using the existing meteorological station network as input is used to validate the performance of PROMET against measured stream flow data. Three aspects of the model performance were validated with good to very good results: the annual variation of the water balance of the whole watershed and selected sub-watersheds, the daily runoff for the whole period at selected gauges and the annual flood peaks and low flows (minimum 7-days average). PROMET is used to investigate the impact of climate change on the water cycle of the Upper Danube. A stochastic climate generator is fed with two scenarios of climate development until 2060. One assumes no future temperature change, the other uses the temperature trends of the IPCC-A1B

  16. Snowmelt water drives higher soil erosion than rainfall water in a mid-high latitude upland watershed

    Science.gov (United States)

    Wu, Yuyang; Ouyang, Wei; Hao, Zengchao; Yang, Bowen; Wang, Li

    2018-01-01

    The impacts of precipitation and temperature on soil erosion are pronounced in mid-high latitude areas, which lead to seasonal variations in soil erosion. Determining the critical erosion periods and the reasons behind the increased erosion loads are essential for soil management decisions. Hence, integrated approaches combining experiments and modelling based on field investigations were applied to investigate watershed soil erosion characteristics and the dynamics of water movement through soils. Long-term and continuous data for surface runoff and soil erosion variation characteristics of uplands in a watershed were observed via five simulations by the Soil and Water Assessment Tool (SWAT). In addition, laboratory experiments were performed to quantify the actual soil infiltrabilities in snowmelt seasons (thawed treatment) and rainy seasons (non-frozen treatment). The results showed that over the course of a year, average surface runoff and soil erosion reached peak values of 31.38 mm and 1.46 t ha-1 a-1, respectively, in the month of April. They also ranked high in July and August, falling in the ranges of 23.73 mm to 24.91 mm and 0.55 t ha-1 a-1 to 0.59 t ha-1 a-1, respectively. With the infiltration time extended, thawed soils showed lower infiltrabilities than non-frozen soils, and the differences in soil infiltration amounts between these two were considerable. These results highlighted that soil erosion was very closely and positively correlated with surface runoff. Soil loss was higher in snowmelt periods than in rainy periods due to the higher surface runoff in early spring, and the decreased soil infiltrability in snowmelt periods contributed much to this higher surface runoff. These findings are helpful for identification of critical soil erosion periods when making soil management before critical months, especially those before snowmelt periods.

  17. Increasing a Community's Knowledge about Drought, Watershed Ecosystems, and Water Quality Through Educational Activities Added to Coastal Cleanup Day Events

    Science.gov (United States)

    Brinker, R.; Allen, L.; Cole, P.; Rho, C.

    2016-12-01

    International Coastal Cleanup Day, held each September, is an effective campaign to bring volunteers together to clean trash from beaches and waterways and document results. Over 500,000 participants cleared over 9 million pounds of trash in 2015. To build on the enthusiasm for this event, the city of Livermore, California's Water Resource Department, the Livermore Valley Joint Unified School District, Livermore Area Recreation and Parks Department created a water education program to embed within the city's Coastal Cleanup Day events. Goals of the education program are to increase awareness of the local watershed and its geographic reach, impacts of climate change and drought on local water supplies, pollution sources and impacts of local pollution on the ocean, positive impacts of a recent plastic bag ban, water quality assessment, and action steps citizens can take to support a healthy watershed. Volunteers collect and test water samples (when water is in the creek) using modified GLOBE and World Water Monitoring Day protocols. Test results are uploaded to the World Water Monitoring Day site and documented on the program web site. Volunteers report that they did not know about watersheds, impacts of local pollution, and water quality components before the education program. Volunteers are encouraged to adopt a creek spot for one year, and continue to collect and document trash. High school and middle school science classes added the water quality testing into curriculum, and regularly visit creek sites to clean the spots and monitor habitats. Each year for the past five years, about 300 volunteers have worked on creek clean-up events, 20 have adopted creek sites, and collected over 4,000 gallons of trash annually. As a result of these efforts, sites have been downgraded from a trash hot spot of concern. Strategies will be shared to expand an established (or start a new) Coastal Cleanup Day event into a successful watershed and climate awareness citizen science

  18. National Audubon Society v. Superior Court: a watershed case integrating the public trust doctrine and California water law

    Energy Technology Data Exchange (ETDEWEB)

    Gaylord, R.K.

    1983-01-01

    Audobon v. Superior Court is a ''watershed'' case in its integration of the public trust doctrine within traditional water law. The public trust doctrine requires the state to exercise a duty of continued supervision over the taking and use of appropriated water. As a result, the state must periodically balance the economic interests served by the water appropriations with the ecological and recreational interests protected under the public trust. The state can best meet this burden by adopting a balancing procedure that includes comprehensive, long-term planning of the economic effects and ecological interests in water appropriation. 78 references.

  19. Stream restoration and sewers impact sources and fluxes of water, carbon, and nutrients in urban watersheds

    Science.gov (United States)

    Pennino, Michael J.; Kaushal, Sujay S.; Mayer, Paul M.; Utz, Ryan M.; Cooper, Curtis A.

    2016-08-01

    An improved understanding of sources and timing of water, carbon, and nutrient fluxes associated with urban infrastructure and stream restoration is critical for guiding effective watershed management globally. We investigated how sources, fluxes, and flowpaths of water, carbon (C), nitrogen (N), and phosphorus (P) shift in response to differences in urban stream restoration and sewer infrastructure. We compared an urban restored stream with two urban degraded streams draining varying levels of urban development and one stream with upland stormwater management systems over a 3-year period. We found that there was significantly decreased peak discharge in response to precipitation events following stream restoration. Similarly, we found that the restored stream showed significantly lower (p management systems and less impervious surface cover in its watershed (13.2 ± 1.9 mm day-1). The restored stream exported most carbon, nitrogen, and phosphorus at relatively lower streamflow than the two more urban catchments, which exported most carbon and nutrients at higher streamflow. Annual exports of total carbon (6.6 ± 0.5 kg ha-1 yr-1), total nitrogen (4.5 ± 0.3 kg ha-1 yr-1), and total phosphorus (161 ± 15 kg ha-1 yr-1) were significantly lower in the restored stream compared to both urban degraded streams (p management systems, for N exports. However, nitrate isotope data suggested that 55 ± 1 % of the nitrate in the urban restored stream was derived from leaky sanitary sewers (during baseflow), statistically similar to the urban degraded streams. These isotopic results as well as additional tracers, including fluoride (added to drinking water) and iodide (contained in dietary salt), suggested that groundwater contamination was a major source of urban nutrient fluxes, which has been less considered compared to upland sources. Overall, leaking sewer pipes are a problem globally and our results suggest that combining stream restoration with restoration of aging sewer

  20. Filling Gaps in Biogeochemical Understanding of Wildfire Effects on Watersheds and Water Quality

    Science.gov (United States)

    Rhoades, Charles; Covino, Timothy; Chow, Alex

    2017-04-01

    Large, high-severity wildfires alter the biogeochemical conditions that determine how watersheds retain and release nutrients and influence stream water quality. These effects are commonly expected to abate within a few years, but recent studies show that post-fire watershed changes can have persistent, but poorly-understood biogeochemical consequences. Owing to the increased frequency and extent of high-severity wildfires predicted for western North America, and the growing awareness of the links between wildfire and clean water supply, there is a need to address these knowledge gaps. For the past 15 years we have tracked stream nutrients, chemistry, temperature, and sediment after the 2002 Hayman Fire, the largest wildfire in Colorado history. Our earlier work showed that headwater catchments that experienced extensive, high-severity forest fires had elevated stream nitrate, temperature, and turbidity for five post-fire years. Recent sampling, conducted 13 and 14 years after the fire, found that turbidity had largely returned to pretreatment levels, but that stream nitrate remained an order of magnitude above pre-fire levels in catchments with extensive high-severity wildfire. Stream temperature and total dissolved nitrogen concentration also remained higher in those catchments compared to unburned streams. Decreased plant demand is the mechanism commonly credited for post-fire nutrient losses, though our current work is evaluating the implications of soil and stream nutrient uptake and supply on persistent nitrogen (N) export from severely-burned catchments. For example, we have measured higher total soil N and higher net N mineralization in severely-burned portions of the Hayman Fire compared to moderately or unburned areas, indicating that higher soil N supply may contribute to N losses from upland soils. Conversely, using a nutrient tracer approach we found reduced N uptake in burned streams, which suggests a switch from the N-limited conditions typical of

  1. Determining Water Quality Trends in the Sacramento-San Joaquin Delta Watershed in the Face of Climate Change

    Science.gov (United States)

    Kynett, K.; Azimi-Gaylon, S.; Doidic, C.

    2014-12-01

    The Sacramento-San Joaquin Delta and Suisun Marsh (Delta) is the largest estuary on the West Coast of the Americas and is a resource of local, State, and national significance. The Delta is simultaneously the most critical component of California's water supply, a primary focus of the state's ecological conservation measures, and a vital resource deeply imperiled by degraded water quality. Delta waterbodies are identified as impaired by salinity, excess nutrients, low dissolved oxygen, pathogens, pesticides, heavy metals, and other contaminants. Climate change is expected to exacerbate the impacts of existing stressors in the Delta and magnify the challenges of managing this natural resource. A clear understanding of the current state of the watershed is needed to better inform scientists, decision makers, and the public about potential impacts from climate change. The Delta Watershed Initiative Network (Delta WIN) leverages the ecological benefits of healthy watersheds, and enhances, expands and creates opportunities for greater watershed health by coordinating with agencies, established programs, and local organizations. At this critical junction, Delta WIN is coordinating data integration and analysis to develop better understanding of the existing and emerging water quality concerns. As first steps, Delta WIN is integrating existing water quality data, analyzing trends, and monitoring to fill data gaps and to evaluate indicators of climate change impacts. Available data will be used for trend analysis; Delta WIN will continue to monitor where data is incomplete and new questions arise. Understanding how climate change conditions may affect water quality will be used to inform efforts to build resilience and maintain water quality levels which sustain aquatic life and human needs. Assessments of historical and new data will aid in recognition of potential climate change impacts and in initiating implementation of best management practices in collaboration with

  2. Water storages and fluxes within the small watershed in continuous permafrost zone

    Science.gov (United States)

    Lebedeva, Liudmila; Makarieva, Olga; Nesterova, Nataliya; Meyer, Hanno; Efremov, Vladimir; Ogonerov, Vasiliy

    2017-04-01

    It is widely accepted that the main source of river runoff in continuous permafrost zone is surface flow and the flow in the seasonally thawing layer. Although the existence of taliks (a layer of year-round unfrozen ground that can be found in permafrost areas) is acknowledged they are usually not considered in the analysis of streamwater sources and in hydrological modelling approaches. The study aims at assessing the possible river sources in small permafrost basin and their contribution to streamflow with special attention to hydrological role of taliks. The study is based on field surveys in 2015 and 2016, the analysis for stable isotopes (δD and δ18O) and the application of a simple mixing model. The Shestakovka River (basin area 170 km2) is a left tributary of the Lena River in the vicinity of Yakutsk city, Eastern Siberia. The climate is dry and continental. Mean air temperature is -9.5°C, precipitation is 240 mm/year, annual runoff depth - 24 mm. Dominant landscapes are pine forest (47% of the watershed area), larch-birch forest (38%) and bogs (14%). Suprapermafrost talik with an area of 58 000 m2 was found on the slope covered by the pine forest in 1980s. Field studies showed that the summer flow depth in talik is 60 mm. In 2015 and 2016 264 water samples from river streams, lakes, snow, rain, suprapermafrost groundwater and ground ice were taken in the Shestakovka River watershed and analyzed for stable isotopes composition. Snow has the lightest isotopic composition that varies between -230 and -275‰ in δD and between -30 and - 37‰ in δ18O. Rain water is on average most enriched in δD (-70…-150‰) and in δ18O (-6…-19‰). River water and surface flow in bogs are depleted during snowmelt (April - May) and enriched at the end of the summer. δ18O and δD concentrations in lake water vary from -20‰ and -185‰ in snowmelt period to -10‰ and -110‰ in July and August respectively. Suprapermafrost groundwater in two taliks has δ18O

  3. Integrated climate/land use/hydrological change scenarios for assessing threats to ecosystem services on California rangelands

    Science.gov (United States)

    Byrd, K. B.; Flint, L. E.; Casey, C. F.; Alvarez, P.; Sleeter, B. M.; Sohl, T.

    2013-12-01

    In California there are over 18 million acres of rangelands in the Central Valley and the interior Coast Range, most of which are privately owned and managed for livestock production. Ranches provide extensive wildlife habitat and generate multiple ecosystem services that carry considerable market and non-market values. These rangelands are under pressure from urbanization and conversion to intensive agriculture, as well as from climate change that can alter the flow of these services. To understand the coupled and isolated impacts of land use and climate change on rangeland ecosystem services, we developed six spatially explicit (250 m) coupled climate/land use/hydrological change scenarios for the Central Valley and oak woodland regions of California consistent with three IPCC emission scenarios - A2, A1B and B1. Three land use land cover (LULC) change scenarios were each integrated with two downscaled global climate models (GCMs) (a warm, wet future and a hot, dry future) and related hydrologic data. We used these scenarios to quantify wildlife habitat, water supply (recharge potential and streamflow) and carbon sequestration on rangelands and to conduct an economic analysis associated with changes in these benefits. The USGS FOREcasting SCEnarios of land-use change model (FORE-SCE), which runs dynamically with downscaled GCM outputs, was used to generate maps of yearly LULC change for each scenario from 2006 to 2100. We used the USGS Basin Characterization Model (BCM), a regional water balance model, to generate change in runoff, recharge, and stream discharge based on land use change and climate change. Metrics derived from model outputs were generated at the landscape scale and for six case-study watersheds. At the landscape scale, over a quarter of the million acres set aside for conservation in the B1 scenario would otherwise be converted to agriculture in the A2 scenario, where temperatures increase by up to 4.5 °C compared to 1.3 °C in the B1 scenario

  4. Stream water chemistry in the arsenic-contaminated Baccu Locci mine watershed (Sardinia, Italy) after remediation.

    Science.gov (United States)

    Ardau, Carla; Podda, Francesca; Da Pelo, Stefania; Frau, Franco

    2013-11-01

    The abandoned Pb-As Baccu Locci mine represents the first and only case of mine site remediation in Sardinia, Italy. Arsenic is the most relevant environmental concern in the Baccu Locci stream watershed, with concentrations in surface waters up to and sometimes over 1 mg/L. The main remediation action consisted in creation of a "storage site", for the collection of contaminated materials from different waste-rock dumps and most of tailings piles occurring along the Baccu Locci stream. This paper reports preliminary results on the level of contamination in the Baccu Locci stream after the completion of remediation measures. Post-remediation stream water chemistry has not substantially changed compared to the pre-remediation situation. In particular, dissolved As maintains an increasing trend along the Baccu Locci stream, with a concentration of about 400 μg/L measured at a distance of 7 km from the storage site. Future monitoring will provide fundamental information on the effectiveness of remediation actions conducted and their applicability to other mine sites in Sardinia. At the stage of mine site characterisation of future remediation plans, it is recommended to pay more attention to the understanding of mineralogical and geochemical processes responsible for pollution. Moreover, mixing of materials with different composition and reactivity in a storage site should require careful consideration and long-term leaching tests.

  5. Estimating snow water equivalent in a Sierra Nevada watershed via spaceborne radiance data assimilation

    Science.gov (United States)

    Li, Dongyue; Durand, Michael; Margulis, Steven A.

    2017-01-01

    This paper demonstrates improved retrieval of snow water equivalent (SWE) from spaceborne passive microwave measurements for the sparsely forested Upper Kern watershed (511 km2) in the southern Sierra Nevada (USA). This is accomplished by assimilating AMSR-E 36.5 GHz measurements into model predictions of SWE at 90 m spatial resolution using the Ensemble Batch Smoother (EnBS) data assimilation framework. For each water year (WY) from 2003 to 2008, SWE was estimated for the accumulation season (1 October to 1 April) with the assimilation of the measurements in the dry snow season (1 December to 28 February). The EnBS SWE estimation was validated against snow courses and snow pillows. On average, the EnBS accumulation season SWE RMSE was 77.4 mm (13.1%, relative to peak accumulation), despite deep snow (average peak SWE of 545 mm). The prior model estimate without assimilation had an accumulation season average RMSE of 119.7 mm. After assimilation, the overall bias of the accumulation season SWE estimates was reduced by 84.2%, and the RMSE reduced by 35.4%. The assimilation also reduced the bias and the RMSE of the 1 April SWE estimates by 80.9% and 45.4%, respectively. The EnBS is expected to work well above tree line and for dry snow.

  6. Evaluating changes in water quality with respect to nonpoint source nutrient management strategies in the Chesapeake Bay Watershed

    Science.gov (United States)

    Keisman, J.; Sekellick, A.; Blomquist, J.; Devereux, O. H.; Hively, W. D.; Johnston, M.; Moyer, D.; Sweeney, J.

    2014-12-01

    Chesapeake Bay is a eutrophic ecosystem with periodic hypoxia and anoxia, algal blooms, diminished submerged aquatic vegetation, and degraded stocks of marine life. Knowledge of the effectiveness of actions taken across the watershed to reduce nitrogen (N) and phosphorus (P) loads to the bay (i.e. "best management practices" or BMPs) is essential to its restoration. While nutrient inputs from point sources (e.g. wastewater treatment plants and other industrial and municipal operations) are tracked, inputs from nonpoint sources, including atmospheric deposition, farms, lawns, septic systems, and stormwater, are difficult to measure. Estimating reductions in nonpoint source inputs attributable to BMPs requires compilation and comparison of data on water quality, climate, land use, point source discharges, and BMP implementation. To explore the relation of changes in nonpoint source inputs and BMP implementation to changes in water quality, a subset of small watersheds (those containing at least 10 years of water quality monitoring data) within the Chesapeake Watershed were selected for study. For these watersheds, data were compiled on geomorphology, demographics, land use, point source discharges, atmospheric deposition, and agricultural practices such as livestock populations, crop acres, and manure and fertilizer application. In addition, data on BMP implementation for 1985-2012 were provided by the Environmental Protection Agency Chesapeake Bay Program Office (CBPO) and the U.S. Department of Agriculture. A spatially referenced nonlinear regression model (SPARROW) provided estimates attributing N and P loads associated with receiving waters to different nutrient sources. A recently developed multiple regression technique ("Weighted Regressions on Time, Discharge and Season" or WRTDS) provided an enhanced understanding of long-term trends in N and P loads and concentrations. A suite of deterministic models developed by the CBPO was used to estimate expected

  7. Quality of Water and Antibiotic Resistance of Escherichia coli from Water Sources of Hilly Tribal Villages with and without Integrated Watershed Management—A One Year Prospective Study

    Science.gov (United States)

    Nerkar, Sandeep S.; Tamhankar, Ashok J.; Khedkar, Smita U.; Stålsby Lundborg, Cecilia

    2014-01-01

    In many hilly tribal areas of the world, water scarcity is a major problem and diarrhoea is common. Poor quality of water also affects the environment. An integrated watershed management programme (IWMP) aims to increase availability of water and to improve life conditions. Globally, there is a lack of information on water contamination, occurrence of diarrhoea and antibiotic resistance, a serious global concern, in relation to IWMP in hilly tribal areas. Therefore, a prospective observational study was conducted during 2011–2012 in six villages in a hilly tribal belt of India, three with and three without implementation of an IWMP, to explore quality of water, diarrhoeal cases in the community and antibiotic resistance of Escherichia coli from water sources. The results showed that physico-chemical quality of water was within limits of safe consumption in all samples. The odds of coliform contamination in water samples was 2.3 times higher in non-watershed management villages (NWMV) compared to integrated watershed management villages (IWMV) (95% CI 0.8–6.45, p = 0.081). The number of diarrhoeal cases (18/663 vs. 42/639, p < 0.05) was lower in IWMV as compared to NWMV. Overall E. coli isolates showed high susceptibility to antibiotics. Resistance to a wider range of antibiotics was observed in NWMV. PMID:24991664

  8. Quality of Water and Antibiotic Resistance of Escherichia coli from Water Sources of Hilly Tribal Villages with and without Integrated Watershed Management—A One Year Prospective Study

    Directory of Open Access Journals (Sweden)

    Sandeep S. Nerkar

    2014-06-01

    Full Text Available In many hilly tribal areas of the world, water scarcity is a major problem and diarrhoea is common. Poor quality of water also affects the environment. An integrated watershed management programme (IWMP aims to increase availability of water and to improve life conditions. Globally, there is a lack of information on water contamination, occurrence of diarrhoea and antibiotic resistance, a serious global concern, in relation to IWMP in hilly tribal areas. Therefore, a prospective observational study was conducted during 2011–2012 in six villages in a hilly tribal belt of India, three with and three without implementation of an IWMP, to explore quality of water, diarrhoeal cases in the community and antibiotic resistance of Escherichia coli from water sources. The results showed that physico-chemical quality of water was within limits of safe consumption in all samples. The odds of coliform contamination in water samples was 2.3 times higher in non-watershed management villages (NWMV compared to integrated watershed management villages (IWMV (95% CI 0.8–6.45, p = 0.081. The number of diarrhoeal cases (18/663 vs. 42/639, p < 0.05 was lower in IWMV as compared to NWMV. Overall E. coli isolates showed high susceptibility to antibiotics. Resistance to a wider range of antibiotics was observed in NWMV.

  9. Quality of water and antibiotic resistance of Escherichia coli from water sources of hilly tribal villages with and without integrated watershed management-a one year prospective study.

    Science.gov (United States)

    Nerkar, Sandeep S; Tamhankar, Ashok J; Khedkar, Smita U; Lundborg, Cecilia Stålsby

    2014-06-01

    In many hilly tribal areas of the world, water scarcity is a major problem and diarrhoea is common. Poor quality of water also affects the environment. An integrated watershed management programme (IWMP) aims to increase availability of water and to improve life conditions. Globally, there is a lack of information on water contamination, occurrence of diarrhoea and antibiotic resistance, a serious global concern, in relation to IWMP in hilly tribal areas. Therefore, a prospective observational study was conducted during 2011–2012 in six villages in a hilly tribal belt of India, three with and three without implementation of an IWMP, to explore quality of water, diarrhoeal cases in the community and antibiotic resistance of Escherichia coli from water sources. The results showed that physico-chemical quality of water was within limits of safe consumption in all samples. The odds of coliform contamination in water samples was 2.3 times higher in non-watershed management villages (NWMV) compared to integrated watershed management villages (IWMV) (95% CI 0.8–6.45, p = 0.081). The number of diarrhoeal cases (18/663 vs. 42/639, p < 0.05) was lower in IWMV as compared to NWMV. Overall E. coli isolates showed high susceptibility to antibiotics. Resistance to a wider range of antibiotics was observed in NWMV.

  10. Cattle-rangeland management practices and perceptions of pastoralists towards rangeland degradation in the Borana zone of southern Ethiopia.

    Science.gov (United States)

    Solomon, T B; Snyman, H A; Smit, G N

    2007-03-01

    A survey was conducted in the Borana pastoral areas of southern Ethiopia to assess current livestock production systems, rangeland management practices and the perceptions of the pastoralists towards rangeland degradation. This information is considered vital to future pastoral development planning and interventions. Data were collected from a total of 20 villages that were identified from 5 peasant associations, namely Did Yabello, Moyatte, Did Harra, Dubuluk and Melbana. The average household size in the study area was 7.23. The majority of the pastoralists relied on both livestock and crop farming. The average livestock holding per household was 14 cattle, 10 goats, 6 sheep and 2 camels. Livestock holdings, with the exception of camels, has shown a declining trend over time. The two most important traditional rangeland management strategies adopted by the pastoralists included burning and mobility, but since 1974/75 burning has no longer been practised. With regard to mobility, the livestock herding falls in two categories, namely: home based and satellite herding. The former involves the herding of milking cows, calves and immature animals (2 years) further away from the encampments. Based on the pastoralists' perceptions, the major constraints on livestock production in descending order, were recurrent drought, feed and water scarcity, animal diseases, predators and communal land ownership. All the respondents considered the condition of the rangelands to have declined dramatically over time. In the past most development policies were based on equilibrium theories that opposed the communal use of the rangelands and traditional range management practices. The way in which the pastoral system affects the rangeland ecosystem functioning is contentious to this theory and the 'tragedy of the commons'. There was also a perceived problem of bush encroachment and the ban on traditional burning practices and recurrent droughts were seen as aggravating factors to this

  11. Weathering processes in the Rio Icacos and Rio Mameyes watersheds in Eastern Puerto Rico: Chapter I in Water quality and landscape processes of four watersheds in eastern Puerto Rico

    Science.gov (United States)

    Buss, Heather L.; White, Arthur F.; Murphy, Sheila F.; Stallard, Robert F.

    2012-01-01

    the fracture zones; during storm events, intense rainfall rapidly raises stream levels and water is flushed through the soil as shallow flow. As a result, weathering constituents that shed into streamwaters are dominated by rindlet-zone weathering processes during base flow and by soil weathering processes during stormflow. The upper reaches of the Mameyes watershed are characterized by regolith more than 35 meters thick in places that contains highly fractured rock embedded in its matrix. Weathering contributions to stream chemistry at base flow are predicted to be more spatially variable in the Mameyes watershed than in the Icacos watershed owing to the more complex subsurface weathering profile of the volcaniclastic bedrocks of the Mameyes watershed.

  12. Simulation of streamflow and the effects of brush management on water yields in the Double Mountain Fork Brazos River watershed, western Texas 1994–2013

    Science.gov (United States)

    Harwell, Glenn R.; Stengel, Victoria G.; Bumgarner, Johnathan R.

    2016-04-20

    The U.S. Geological Survey, in cooperation with the City of Lubbock and the Texas State Soil and Water Conservation Board, developed and calibrated a Soil and Water Assessment Tool watershed model of the Double Mountain Fork Brazos River watershed in western Texas to simulate monthly mean streamflow and to evaluate the effects of brush management on water yields in the watershed, particularly to Lake Alan Henry, for calendar years 1994–2013. Model simulations were done to quantify the possible change in water yield of individual subbasins in the Double Mountain Fork Brazos River watershed as a result of the replacement of shrubland (brush) with grassland. The simulation results will serve as a tool for resource managers to guide brush-management efforts.

  13. Simulation of streamflow and the effects of brush management on water yields in the upper Guadalupe River watershed, south-central Texas, 1995-2010

    Science.gov (United States)

    Bumgarner, Johnathan R.; Thompson, Florence E.

    2012-01-01

    The U.S. Geological Survey, in cooperation with the Texas State Soil and Water Conservation Board and the Upper Guadalupe River Authority, developed and calibrated a Soil and Water Assessment Tool watershed model of the upper Guadalupe River watershed in south-central Texas to simulate streamflow and the effects of brush management on water yields in the watershed and to Canyon Lake for 1995–2010. Model simulations were done to quantify the possible change in water yield of individual subbasins in the upper Guadalupe River watershed as a result of the replacement of ashe juniper (Juniperus ashei) with grasslands. The simulation results will serve as a tool for resource managers to guide their brush-management efforts.

  14. Dynamic modeling of organophosphate pesticide load in surface water in the northern San Joaquin Valley watershed of California

    Energy Technology Data Exchange (ETDEWEB)

    Luo Yuzhou [Department of Land, Air and Water Resources, University of California, Davis, CA 95616 (United States); Institute of Watershed Science and Environmental Ecology, Wenzhou Medical College, Wenzhou, 325000 (China); Zhang Xuyang [Department of Land, Air and Water Resources, University of California, Davis, CA 95616 (United States); Liu Xingmei [Department of Land, Air and Water Resources, University of California, Davis, CA 95616 (United States); Institute of Soil, Water and Environmental Science, Zhejiang University, Hangzhou 310029 (China); Ficklin, Darren [Department of Land, Air and Water Resources, University of California, Davis, CA 95616 (United States); Zhang Minghua [Department of Land, Air and Water Resources, University of California, Davis, CA 95616 (United States); Institute of Watershed Science and Environmental Ecology, Wenzhou Medical College, Wenzhou, 325000 (China)], E-mail: mhzhang@ucdavis.edu

    2008-12-15

    The hydrology, sediment, and pesticide transport components of the Soil and Water Assessment Tool (SWAT) were evaluated on the northern San Joaquin Valley watershed of California. The Nash-Sutcliffe coefficients for monthly stream flow and sediment load ranged from 0.49 to 0.99 over the watershed during the study period of 1992-2005. The calibrated SWAT model was applied to simulate fate and transport processes of two organophosphate pesticides of diazinon and chlorpyrifos at watershed scale. The model generated satisfactory predictions of dissolved pesticide loads relative to the monitoring data. The model also showed great success in capturing spatial patterns of dissolved diazinon and chlorpyrifos loads according to the soil properties and landscape morphology over the large agricultural watershed. This study indicated that curve number was the major factor influencing the hydrology while pesticide fate and transport were mainly affected by surface runoff and pesticide application and in the study area. - Major factors governing the instream loads of organophosphate pesticides are magnitude and timing of surface runoff and pesticide application.

  15. Assessment of Water Quality and Identification of Polluted Risky Regions Based on Field Observations & GIS in the Honghe River Watershed, China

    Science.gov (United States)

    Yan, Chang-An; Zhang, Wanchang; Zhang, Zhijie; Liu, Yuanmin; Deng, Cai; Nie, Ning

    2015-01-01

    Water quality assessment at the watershed scale requires not only an investigation of water pollution and the recognition of main pollution factors, but also the identification of polluted risky regions resulted in polluted surrounding river sections. To realize this objective, we collected water samplings from 67 sampling sites in the Honghe River watershed of China with Grid GIS method to analyze six parameters including dissolved oxygen (DO), ammonia nitrogen (NH3-N), nitrate nitrogen (NO3-N), nitrite nitrogen (NO2-N), total nitrogen (TN) and total phosphorus (TP). Single factor pollution index and comprehensive pollution index were adopted to explore main water pollutants and evaluate water quality pollution level. Based on two evaluate methods, Geo-statistical analysis and Geographical Information System (GIS) were used to visualize the spatial pollution characteristics and identifying potential polluted risky regions. The results indicated that the general water quality in the watershed has been exposed to various pollutants, in which TP, NO2-N and TN were the main pollutants and seriously exceeded the standard of Category III. The zones of TP, TN, DO, NO2-N and NH3-N pollution covered 99.07%, 62.22%, 59.72%, 37.34% and 13.82% of the watershed respectively, and they were from medium to serious polluted. 83.27% of the watershed in total was polluted by comprehensive pollutants. These conclusions may provide useful and effective information for watershed water pollution control and management. PMID:25768942

  16. Management-oriented sensitivity analysis for pesticide transport in watershed-scale water quality modeling using SWAT

    Energy Technology Data Exchange (ETDEWEB)

    Luo Yuzhou [University of California, Davis, CA 95616 (United States); Wenzhou Medical College, Wenzhou 325035 (China); Zhang Minghua, E-mail: mhzhang@ucdavis.ed [University of California, Davis, CA 95616 (United States); Wenzhou Medical College, Wenzhou 325035 (China)

    2009-12-15

    The Soil and Water Assessment Tool (SWAT) was calibrated for hydrology conditions in an agricultural watershed of Orestimba Creek, California, and applied to simulate fate and transport of two organophosphate pesticides chlorpyrifos and diazinon. The model showed capability in evaluating pesticide fate and transport processes in agricultural fields and instream network. Management-oriented sensitivity analysis was conducted by applied stochastic SWAT simulations for pesticide distribution. Results of sensitivity analysis identified the governing processes in pesticide outputs as surface runoff, soil erosion, and sedimentation in the study area. By incorporating sensitive parameters in pesticide transport simulation, effects of structural best management practices (BMPs) in improving surface water quality were demonstrated by SWAT modeling. This study also recommends conservation practices designed to reduce field yield and in-stream transport capacity of sediment, such as filter strip, grassed waterway, crop residue management, and tailwater pond to be implemented in the Orestimba Creek watershed. - Selected structural BMPs are recommended for reducing loads of OP pesticides.

  17. Multi isotopic characterization (Li-Cu-Zn-Pb) of waste waters pollution in a small watershed (Loire River basin, France)

    Science.gov (United States)

    Millot, R.; Desaulty, A. M.; Perret, S.; Bourrain, X.

    2016-12-01

    The goal of this study is to use multi-isotopic signature to track the pollution in surface waters, and to understand the complex processes causing the metals mobilization and transport in the environment. In the present study, we investigate waste water releases from a hospital water treatment plant and its potential impact in a small river basin near Orléans in France (Egoutier watershed: 15 km²and 5 km long). We decided to monitor this small watershed which is poorly urbanized in the Loire river basin. Its spring is located in a pristine area (forested area), while it is only impacted some kilometers further by the releases rich in metals coming from a hospital water treatment plant. A sampling of these liquid effluents as well as dissolved load and sediment from upstream to downstream was realized and their concentrations and isotopic data were determined. Isotopic ratios were measured using a MC-ICP-MS at BRGM, after a specific protocol of purification for each isotopic systematics. Lithium isotopic compositions are rather homogeneous in river waters along the main course of the stream. The waste water signal is very different from the natural background with significant heavy lithium contribution (high δ7Li). Lead isotopic compositions are rather homogenous in river waters and sediments with values close to geologic background. For Zn, the sediments with high concentrations and depleted isotopic compositions (low δ66Zn), typical of an anthropic pollution, are strongly impacted. The analyses of Cu isotopes in sediments show the impact of waster waters, but also isotopic fractionations due to redox processes in the watershed. To better understand these processes controlling the release of metals in water, sequential extractions on sediments are in progress under laboratory conditions and will provide important constraints for metal distribution in this river basin.

  18. Groundwater and surface-water interaction within the upper Smith River Watershed, Montana 2006-2010

    Science.gov (United States)

    Caldwell, Rodney R.; Eddy-Miller, Cheryl A.

    2013-01-01

    The 125-mile long Smith River, a tributary of the Missouri River, is highly valued as an agricultural resource and for its many recreational uses. During a drought starting in about 1999, streamflow was insufficient to meet all of the irrigation demands, much less maintain streamflow needed for boating and viable fish habitat. In 2006, the U.S. Geological Survey, in cooperation with the Meagher County Conservation District, initiated a multi-year hydrologic investigation of the Smith River watershed. This investigation was designed to increase understanding of the water resources of the upper Smith River watershed and develop a detailed description of groundwater and surface-water interactions. A combination of methods, including miscellaneous and continuous groundwater-level, stream-stage, water-temperature, and streamflow monitoring was used to assess the hydrologic system and the spatial and temporal variability of groundwater and surface-water interactions. Collectively, data are in agreement and show: (1) the hydraulic connectedness of groundwater and surface water, (2) the presence of both losing and gaining stream reaches, (3) dynamic changes in direction and magnitude of water flow between the stream and groundwater with time, (4) the effects of local flood irrigation on groundwater levels and gradients in the watershed, and (5) evidence and timing of irrigation return flows to area streams. Groundwater flow within the alluvium and older (Tertiary) basin-fill sediments generally followed land-surface topography from the uplands to the axis of alluvial valleys of the Smith River and its tributaries. Groundwater levels were typically highest in the monitoring wells located within and adjacent to streams in late spring or early summer, likely affected by recharge from snowmelt and local precipitation, leakage from losing streams and canals, and recharge from local flood irrigation. The effects of flood irrigation resulted in increased hydraulic gradients

  19. Application of Large-Scale, Multi-Resolution Watershed Modeling Framework Using the Hydrologic and Water Quality System (HAWQS

    Directory of Open Access Journals (Sweden)

    Haw Yen

    2016-04-01

    Full Text Available In recent years, large-scale watershed modeling has been implemented broadly in the field of water resources planning and management. Complex hydrological, sediment, and nutrient processes can be simulated by sophisticated watershed simulation models for important issues such as water resources allocation, sediment transport, and pollution control. Among commonly adopted models, the Soil and Water Assessment Tool (SWAT has been demonstrated to provide superior performance with a large amount of referencing databases. However, it is cumbersome to perform tedious initialization steps such as preparing inputs and developing a model with each changing targeted study area. In this study, the Hydrologic and Water Quality System (HAWQS is introduced to serve as a national-scale Decision Support System (DSS to conduct challenging watershed modeling tasks. HAWQS is a web-based DSS developed and maintained by Texas A & M University, and supported by the U.S. Environmental Protection Agency. Three different spatial resolutions of Hydrologic Unit Code (HUC8, HUC10, and HUC12 and three temporal scales (time steps in daily/monthly/annual are available as alternatives for general users. In addition, users can specify preferred values of model parameters instead of using the pre-defined sets. With the aid of HAWQS, users can generate a preliminarily calibrated SWAT project within a few minutes by only providing the ending HUC number of the targeted watershed and the simulation period. In the case study, HAWQS was implemented on the Illinois River Basin, USA, with graphical demonstrations and associated analytical results. Scientists and/or decision-makers can take advantage of the HAWQS framework while conducting relevant topics or policies in the future.

  20. Estimating watershed degradation over the last century and its impact on water-treatment costs for the world’s large cities

    Science.gov (United States)

    McDonald, Robert I.; Weber, Katherine F.; Padowski, Julie; Boucher, Tim; Shemie, Daniel

    2016-01-01

    Urban water systems are impacted by land use within their source watersheds, as it affects raw water quality and thus the costs of water treatment. However, global estimates of the effect of land cover change on urban water-treatment costs have been hampered by a lack of global information on urban source watersheds. Here, we use a unique map of the urban source watersheds for 309 large cities (population > 750,000), combined with long-term data on anthropogenic land-use change in their source watersheds and data on water-treatment costs. We show that anthropogenic activity is highly correlated with sediment and nutrient pollution levels, which is in turn highly correlated with treatment costs. Over our study period (1900–2005), median population density has increased by a factor of 5.4 in urban source watersheds, whereas ranching and cropland use have increased by a factor of 3.4 and 2.0, respectively. Nearly all (90%) of urban source watersheds have had some level of watershed degradation, with the average pollutant yield of urban source watersheds increasing by 40% for sediment, 47% for phosphorus, and 119% for nitrogen. We estimate the degradation of watersheds over our study period has impacted treatment costs for 29% of cities globally, with operation and maintenance costs for impacted cities increasing on average by 53 ± 5% and replacement capital costs increasing by 44 ± 14%. We discuss why this widespread degradation might be occurring, and strategies cities have used to slow natural land cover loss. PMID:27457941

  1. Contrasting nitrogen fate in watersheds using agricultural and water quality information

    Science.gov (United States)

    Essaid, Hedeff I.; Baker, Nancy T.; McCarthy, Kathleen A.

    2016-01-01

    Surplus nitrogen (N) estimates, principal component analysis (PCA), and end-member mixing analysis (EMMA) were used in a multisite comparison contrasting the fate of N in diverse agricultural watersheds. We applied PCA-EMMA in 10 watersheds located in Indiana, Iowa, Maryland, Nebraska, Mississippi, and Washington ranging in size from 5 to 1254 km2 with four nested watersheds. Watershed Surplus N was determined by subtracting estimates of crop uptake and volatilization from estimates of N input from atmospheric deposition, plant fixation, fertilizer, and manure for the period from 1987 to 2004. Watershed average Surplus N ranged from 11 to 52 kg N ha−1 and from 9 to 32% of N input. Solute concentrations in streams, overland runoff, tile drainage, groundwater (GW), streambeds, and the unsaturated zone were used in the PCA-EMMA procedure to identify independent components contributing to observed stream concentration variability and the end-members contributing to streamflow and NO3 load. End-members included dilute runoff, agricultural runoff, benthic-processing, tile drainage, and oxic and anoxic GW. Surplus N was larger in watersheds with more permeable soils (Washington, Nebraska, and Maryland) that allowed greater infiltration, and oxic GW was the primary source of NO3 load. Subsurface transport of NO3 in these watersheds resulted in some removal of Surplus N by denitrification. In less permeable watersheds (Iowa, Indiana, and Mississippi), NO3 was rapidly transported to the stream by tile drainage and runoff with little removal. Evidence of streambed removal of NO3 by benthic diatoms was observed in the larger watersheds.

  2. Quantifying Hillslope to Watershed Erosional Response Following Wildfire

    Science.gov (United States)

    Vega, S.; Pierson, F. B.; Williams, C. J.; Brooks, E. S.; Pierce, J. L.; Roehner, C.

    2016-12-01

    The frequency and severity of wildfires is increasing across western US sagebrush steppe rangelands as the result of warming climate conditions and invasive plant species. Following wildfire, the soil surface is left with little vegetation, exposing it to erosion by wind and water. Erosion following wildfires is a concern among land managers due to the threat it poses to resources, infrastructure, and human health. Most post-fire erosion research has used artificial rainfall. This study uses natural rainfall and a network of silt fences to quantify hillslope to watershed scale erosion response following the 2015 Soda Fire that burned 113,300 ha in southwestern Idaho and southeastern Oregon. In this study, we will evaluate the drivers of erosion over multiple spatial scales and assess the recovery of vegetation and soil water repellency for a two year period post-fire. We installed a network of silt fences over long and short hillslope distances and in swales within a 130 ha catchment within the Reynolds Creek Experimental Watershed in southwestern Idaho, USA. The overall study design consists of thirty silt fences spanning north and south facing aspects, an existing weir measuring watershed streamflow and sediment discharge, and two meteorological stations. The erosional response following the fire was mainly driven by wind and snowmelt. The swales produced the most sediment compared to the long and short hillslopes. On the south facing aspect the long and short hillslopes did not produce any sediment whereas on the north facing aspect the swales produced the most sediment. This presentation summarizes these preliminary first year hydrologic and erosion responses. The results provide data for determining the drivers for erosion at different spatial scales, advance understanding of post-fire hillslope to watershed erosional responses, and offer insight into recovery of vegetation and soil water repellency post-fire. This study will aid land management agencies

  3. Occurrences of pharmaceuticals in drinking water sources of major river watersheds, China.

    Science.gov (United States)

    Sun, Jing; Luo, Qian; Wang, Donghong; Wang, Zijian

    2015-07-01

    Pharmaceuticals in drinking water sources (DWSs) have raised significant concerns for their persistent input and potential human health risks. Currently, little is known about the occurrence of pharmaceuticals in DWSs in China. In this study, a survey for multi-class pharmaceuticals in DWSs of five major river watersheds in China was conducted from 2012 to 2013. Samples were collected from 25 sampling sites in rivers and reservoirs. 135 pharmaceuticals were analyzed using solid-phase extraction and ultra-performance liquid chromatography tandem mass spectrometry. The results showed that a total of 70 pharmaceuticals were present in the samples, and the most frequently detected ones included sulfonamides, macrolides, antiepileptic drugs, anti-inflammatory drugs, and β-blockers, etc. Amongst these, maximum concentrations of lincomycin, sulfamethoxazole, acetaminophen and paraxanthine were between 44 ng/L and 134 ng/L, and those of metoprolol, diphenhydramine, venlafaxine, nalidixic acid and androstenedione were less than 1 ng/L. Concentrations of the two that were most persistent, DEET and carbamazepine, were 0.8-10.2 ng/L and 0.01-3.5 ng/L, respectively. Higher concentrations of cotinine were observed in warm season than in cold season, while concentrations of lincomycin were the opposite. In a causality analysis, the occurrence of pharmaceuticals in DWSs depends mainly on the detection limits of the methods, their usage and the persistence in the aquatic environment. Copyright © 2015 Elsevier Inc. All rights reserved.

  4. Spatial variations in the relationships between land use and water quality across an urbanization gradient in the watersheds of Northern Georgia, USA.

    Science.gov (United States)

    Tu, Jun

    2013-01-01

    A spatial statistical technique, Geographically Weighted Regression (GWR) is applied to study the spatial variations in the relationships between four land use indicators, including percentages of urban land, forest, agricultural land, and wetland, and eight water quality indicators including specific conductance (SC), dissolved oxygen, dissolved nutrients, and dissolved organic carbon, in the watersheds of northern Georgia, USA. The results show that GWR has better model performance than ordinary least squares regression (OLS) to analyze the relationships between land use and water quality. There are great spatial variations in the relationships affected by the urbanization level of watersheds. The relationships between urban land and SC are stronger in less-urbanized watersheds, while those between urban land and dissolved nutrients are stronger in highly-urbanized watersheds. Percentage of forest is an indicator of good water quality. Agricultural land is usually associated with good water quality in highly-urbanized watersheds, but might be related to water pollution in less-urbanized watersheds. This study confirms the results obtained from a similar study in eastern Massachusetts, and so suggest that GWR technique is a very useful tool in water environmental research and also has the potential to be applied to other fields of environmental studies and management in other regions.

  5. Farmer Resettlements and Water Energy Stresses Arising From Aggravating Drought Conditions in Mahaweli River Watershed, Sri Lanka

    Science.gov (United States)

    Thabrew, L.

    2012-12-01

    Climate change is expected to cause significant changes in water quantity and water quality in river basins throughout the world, with particularly significant impacts in developing regions. Climate change effects are often exacerbated by other simultaneous activities in developing countries, such as population growth, reliance on subsistence agriculture, and expanding provision of electricity. Each of these activities requires access to readily-available freshwater. For example, population growth requires more water for irrigation as food production needs increase. Additionally, water is needed for generating electricity in hydropower facilities as well as other facilities, which require water to run steam turbines or to cool facilities. As such, many developing countries face the real and immediate need to anticipate and adapt to climatic stresses on water resources in both the agricultural and residential sectors. Water withdrawal in both of these sectors is largely driven by individual behaviors, such as electricity use in the home and irrigation practices on farmland, aggregated at the household, community, and regional level. Our ongoing project in Sri Lanka focuses on understanding aforementioned issues in coupled natural and human systems in the Mahaweli River Watershed (MWR) to inform decision-makers to streamline policies and strategies for effective adaptation to worsening drought conditions. MWR produces more than 60% of the rice demand and nearly 40% of the energy requirement of the country. Although irrigation is currently the sector that withdraws the most water, with government plans for resettling farmer communities and developing new urban centers in the region by 2030, electricity production is expected to compete for water against irrigation in the future. Thus, understanding the water-energy nexus is crucial to planning for conservation and efficiency. Through a pilot survey conducted by our interdisciplinary research team, in five locations in

  6. Working for Water: A Transdisciplinary Collaboration for Wetlands Restoration in an Urbanizing Watershed

    Science.gov (United States)

    In 2013, I collaborated with staff at the Environmental Protection Agency’s Atlantic Ecology Division to explore the public perceptions of services and disservices associated with restoration of riparian areas and wetlands in the urbanizing Woonasquatucket River watershed i...

  7. Continuous evapotranspiration monitoring and water stress at watershed scale in a Mediterranean oak savanna

    Science.gov (United States)

    Carpintero, E.; González Dugo, M. P.; Hain, C.; Nieto, H.; Gao, F.; Andreu, A.; Kustas, W. P.; Anderson, M. C.

    2016-10-01

    The regular monitoring of the evapotranspiration rates and their links with vegetation conditions and soil moisture may support management and hydrological planning leading to reduce the economic and environmental vulnerability of complex water-controlled Mediterranean ecosystems. In this work, the monitoring of water use over a basin with a predominant oak savanna (known in Spain as dehesa) was conducted for two years, 2013 and 2014, monitoring ET at both fine spatial and temporal resolution in different seasons. A global 5 km daily ET product, developed with the ALEXI model and MODIS day-night temperature difference, was used as starting point. Flux estimations with higher spatial resolutions were obtained with the associated flux disaggregation scheme, DisALEXI, using surface temperature data from the polar orbiting satellites MODIS (1 Km, daily) and Landsat 7/8 (60-120m and sharpened to 30m, 16 days) and the previously estimated coarse resolution fluxes. The results achieved supported the ability of this scheme to accurately estimate daytime-integrated energy fluxes over this system, using input data with different spatio-temporal resolution and without the need for ground observations. Daily ET series at 30 m spatial resolution, generated using STARFM fusion technique, has provided a significant improvement in spatial heterogeneity assessment of the ET series, with RMSE values of 0.56 and 0.68 mm/day for each year, representing an enhancement with respect to interpolated Landsat series. In summary, this approach was demostrated to be robust and operative to map ET at watershed scale with a suitable spatial and temporal resolution for applications over the dehesa ecosystem.

  8. Temporal-spatial distribution of non-point source pollution in a drinking water source reservoir watershed based on SWAT

    Directory of Open Access Journals (Sweden)

    M. Wang

    2015-05-01

    Full Text Available The conservation of drinking water source reservoirs has a close relationship between regional economic development and people’s livelihood. Research on the non-point pollution characteristics in its watershed is crucial for reservoir security. Tang Pu Reservoir watershed was selected as the study area. The non-point pollution model of Tang Pu Reservoir was established based on the SWAT (Soil and Water Assessment Tool model. The model was adjusted to analyse the temporal-spatial distribution patterns of total nitrogen (TN and total phosphorus (TP. The results showed that the loss of TN and TP in the reservoir watershed were related to precipitation in flood season. And the annual changes showed an "M" shape. It was found that the contribution of loss of TN and TP accounted for 84.5% and 85.3% in high flow years, and for 70.3% and 69.7% in low flow years, respectively. The contributions in normal flow years were 62.9% and 63.3%, respectively. The TN and TP mainly arise from Wangtan town, Gulai town, and Wangyuan town, etc. In addition, it was found that the source of TN and TP showed consistency in space.

  9. Land Use and Hydrologic Sensitivities of In-stream Water Quality in Complex Coastal-urban Watersheds

    Science.gov (United States)

    Abdul-Aziz, O. I.; Ahmed, S.

    2016-12-01

    We employed sensitivity analysis to study the complex interactions of various water quality indicators with their drivers in the coastal-urban watersheds of southeast Florida, U.S.A. The total nitrogen (TN), total phosphorus (TP), chlorophyll-a (Chla), and dissolved oxygen (DO) were used to represent the stream water quality. Land use/cover and hydrologic variables along with the upstream (inlet) concentrations and distance from the coastal outlet were used to represent the sources and drivers of stream water quality at each monitoring station. Separate analyses were performed for the wet and dry seasons, acknowledging the variable climatic influence in different seasons. Power-law based nonlinear partial least square (PLS) regression models were developed with bootstrap resampling to achieve a robust estimation of parameters. The model showed good performance in both wet and dry seasons. The estimated model parameters were used to analytically derive relative sensitivity coefficients to determine the relative influence of different drivers on the stream water quality. Numerical sensitivity analyses were also performed with a range of perturbed model drivers to estimate the changes of stream water quality under different changing scenarios of land use/cover and hydrologic variables. Results showed that the major sources of in-stream pollutants were the agricultural land uses and the upstream sources. In both wet and dry seasons, TN showed relatively strong sensitivity to the upstream concentrations and distance from the coastal outlet; whereas TP and Chla showed relatively high sensitivity to the upstream concentrations and the watershed land uses. For DO, relatively strong sensitivity was found to the groundwater depth and watershed hydrology, respectively, in the wet and dry seasons. The sensitivity coefficients and mechanistic insights obtained from the study will guide the management of urban stream water quality to maintain healthy aquatic ecosystems.

  10. Streamflow, groundwater hydrology, and water quality in the upper Coleto Creek watershed in southeast Texas, 2009–10

    Science.gov (United States)

    Braun, Christopher L.; Lambert, Rebecca B.

    2011-01-01

    The U.S. Geological Survey (USGS), in cooperation with the Goliad County Groundwater Conservation District, Victoria County Groundwater Conservation District, Pecan Valley Groundwater Conservation District, Guadalupe-Blanco River Authority, and San Antonio River Authority, did a study to examine the hydrology and stream-aquifer interactions in the upper Coleto Creek watershed. Findings of the study will enhance the scientific understanding of the study-area hydrology and be used to support water-management decisions to help ensure protection of the Evangeline aquifer and surface-water resources in the study area. This report describes the results of streamflow measurements, groundwater-level measurements, and water quality (from both surface-water and groundwater sites) collected from three sampling events (July–August 2009, January 2010, and June 2010) designed to characterize groundwater (from the Evangeline aquifer) and surface water, and the interaction between them, in the upper Coleto Creek watershed upstream from Coleto Creek Reservoir in southeast Texas. This report also provides a baseline level of water quality for the upper Coleto Creek watershed. Three surface-water gain-loss surveys—July 29–30, 2009, January 11–13, 2010, and June 21–22, 2010—were done under differing hydrologic conditions to determine the locations and amounts of streamflow recharging or discharging from the Evangeline aquifer. During periods when flow in the reaches of the upper Coleto Creek watershed was common (such as June 2010, when 12 of 25 reaches were flowing) or probable (such as January 2010, when 22 of 25 reaches were flowing), most of the reaches appeared to be gaining (86 percent in January 2010 and 92 percent in June 2010); however, during drought conditions (July 2009), streamflow was negligible in the entire upper Coleto Creek watershed; streamflow was observed in only two reaches during this period, one that receives inflow directly from Audilet Spring and

  11. An information system design for watershed-wide modeling of water loss to the atmosphere using remote sensing techniques

    Science.gov (United States)

    Khorram, S.

    1977-01-01

    Results are presented of a study intended to develop a general location-specific remote-sensing procedure for watershed-wide estimation of water loss to the atmosphere by evaporation and transpiration. The general approach involves a stepwise sequence of required information definition (input data), appropriate sample design, mathematical modeling, and evaluation of results. More specifically, the remote sensing-aided system developed to evaluate evapotranspiration employs a basic two-stage two-phase sample of three information resolution levels. Based on the discussed design, documentation, and feasibility analysis to yield timely, relatively accurate, and cost-effective evapotranspiration estimates on a watershed or subwatershed basis, work is now proceeding to implement this remote sensing-aided system.

  12. Evaluation of spatial and temporal water quality in the Akkaya dam watershed (Niğde, Turkey) and management implications

    Science.gov (United States)

    Yaşar Korkanç, Selma; Kayıkçı, Sedef; Korkanç, Mustafa

    2017-05-01

    The aim of this study is to investigate the water pollution in the Akkaya Dam watershed spatially and temporally and put forward management suggestions in a watershed scale. For this purpose, monthly water sampling was performed from 11 sampling stations on streams that fed the dam. According to land surveys they have a potential to inflict pollution to the dam. Thus the physical and chemical parameters (i.e. pH, dissolved oxygen, electrical conductivity, temperature, chemical oxygen demand, turbidity and suspended solids) were monitored monthly for 1-year period. Chloride, sulfate, total nitrogen, ammonium, nitrite, nitrate were monitored for a 6-month period, and the results were evaluated in accordance with the Turkish Regulation of Surface Water Quality Management. Results of the study show that the most important reasons for the pollution in the dam are caused by domestic and industrial wastewaters, which were released to the system without being treated, or without being sufficiently treated, and also of agricultural activities. It was determined that electrical conductivity, dissolved oxygen, turbidity, chemical oxygen demand, suspended solids, nitrite, nitrate, total nitrogen, sulfate, and chloride parameters which were high at the sampling stations where domestic and industrial wastewaters discharge were present. pH and temperature demonstrate a difference at a significant level by seasons. As a result of the study, it was determined that the water was of IVth quality in terms of nitrate, chemical oxygen demand, and total nitrogen, and it was of IIIrd quality water with respect to ammonium, electrical conductivity, and dissolved oxygen. It was observed that the dam outflow water was of IVth quality with respect to nitrate, chemical oxygen demand, and total nitrogen, and of IIIrd quality with respect to dissolved oxygen and electrical conductivity. It is considered that the pollution problem in the Akkaya Dam can only be resolved with prevention studies on

  13. Heihe Watershed Allied Telemetry Experimental Research (HiWATER): An Integrated Remote Sensing Experiment on Hydrological and Ecological Processes

    Science.gov (United States)

    Li, X.; Liu, S.; Xiao, Q.; Ma, M.; Jin, R.; Che, T.

    2012-12-01

    A major research plan entitled "Integrated research on the eco-hydrological process of the Heihe River Basin" was launched by the National Natural Science Foundation of China in 2010. One of the key aims of this research plan is to establish a research platform that integrates observation, data management, and model simulation to foster 21st-century watershed science in China. Based on the diverse needs of interdisciplinary studies within this research plan, a program called the Heihe Watershed Allied Telemetry Experimental Research (HiWATER) is implemented. The overall objective of HiWATER is to improve the observability of hydrological and ecological processes, to build a world-class watershed observing system and to enhance the application ability of remote sensing in integrated eco-hydrological study and water recourse management at basin scale. We introduce the background, scientific objectives and experimental design of the HiWATER. The highlights are using flux observing matrix and eco-hydrological wireless sensor network to capture multi-scale heterogeneities, in order to challenge the complex issues such as heterogeneity, scaling, uncertainty, and closing water cycle at watershed scale. HiWATER has formally kicked off in May 2012 and will last four years till 2015. HiWATER encompasses fundamental experiments, thematic experiments, application experiments, remote sensing methods development and products generation, and an integrated information system. (1) Fundamental experiments: a) Microwave radiometer, imaging spectrometer, thermal imaging camera, light detection and ranging (LiDAR) and other sensors are used in the airborne missions to observe key eco-hydrological parameters. b) A comprehensive hydrometeorological observation network has been established in the entire Heihe River Basin, in order to provide more representative model parameters and forcing data. c) An eco-hydrological wireless sensor network (WSN) has been installed to capture the spatial

  14. A decision support system for water supply in watersheds with recurrent wildfires

    Science.gov (United States)

    Santos, Regina; Fernandes, Luís; Pereira, Mário; Cortes, Rui; Pacheco, Fernando

    2015-04-01

    area which was covered by scrubs (69%), forests (22%) and heterogeneous agricultural areas (9%). A close relationship was found between the concentration of phosphorus in river water and the occurrence of forest fires. The annual and monthly phosphorus concentrations are influenced by the burned area and the river flow discharge. However, the hydrologic conditions prevail in the sense that, for similar values of burnt area, the maximum phosphorous concentration is higher in dry than in wet years. In addition, the phosphorus concentrations in the water bodies exceeded the limits imposed by the National and European legislation for good ecological status, human consumption and multiple uses mostly in last years of the study period. The fire frequency is a key variable in the planning and management of water bodies within a fire-prone watershed. The impacts of wildfires on water quality may become periodical instead of occasional as a consequence of the reduced precipitation and increased fire frequency and intensity projected for the near future climate. This work was supported by national funds by FCT - Portuguese Foundation for Science and Technology, under the project PEst-OE/AGR/UI4033/2014 and by the project SUSTAINSYS: Environmental Sustainable Agro-Forestry Systems (NORTE-07-0124-FEDER-000044), financed by the North Portugal Regional Operational Programme (ON.2 - O Novo Norte), under the National Strategic Reference Framework (QREN), through the European Regional Development Fund (FEDER), as well as by National Funds (PIDDAC) through the Portuguese Foundation for Science and Technology (FCT/MEC).

  15. Simulating Water and Nutrient Transport in an Urbanizing Agricultural Watershed with Lake-Level Regulation Using a Coupled Modeling Approach

    Science.gov (United States)

    Chen, X.; Motew, M.; Booth, E.; Carpenter, S. R.; Steven, L. I.; Kucharik, C. J.

    2015-12-01

    The Yahara River basin located in southern Wisconsin is a watershed with long-term eutrophication issues due largely to a thriving dairy industry upstream of the Madison chain of lakes. Steady phosphorus loading from manure production and other sources has contributed directly to blue-green algae blooms and poor water quality in the lakes and river system, and is often viewed as the most important environmental problem to solve in the region. In this study, the daily streamflow and monthly nitrogen (N), sediment and phosphorus (P) transport, as well as the lake levels in the Yahara River basin are simulated using a physically-based hydrologic routing model: the Terrestrial Hydrology Model with Biogeochemistry (THMB). The original model includes representation of water and nitrogen transport but as part of this work, P transport and lake regulation are added into the model. The modified THMB model is coupled with the AgroIBIS-VSF agroecosystem model to represent dynamic coupling between agricultural management in the watershed, and N, P, and sediment transport to lakes and streams. We will present model calibration and validation results that demonstrate the hydrologic routing capability of THMB for a spatial resolution of 220m, several orders of magnitude finer than attempted previously with THMB. The calibrated modeling system is being used to simulate the impacts of climate change and land management on biogeochemistry in the Yahara watershed under four different pathways of change to the year 2070 (Yahara 2070). These scenarios are Abandonment and Renewal, Accelerated Innovation, Connected Communities and Nested Watersheds, which are used to better understand how future decision-making influences the provisioning and trade-offs of ecosystem services.

  16. Water repellency, plants, agriculture abandonment and fire in citrus plantations. The Canyoles river watershed study site

    Science.gov (United States)

    Cerdà, Artemi; Jordán, Antonio; Doerr, Stefan Helmut

    2017-04-01

    Soil water repellency (SWR) is a key soil property that determine the soil and water losses, soil fertility and plant development. Although until the 90's the soil water repellency was seeing as an uncommon soil characteristic, now is considered a key soil property to understand the soil hydrology (Alanís et al., 2016; Hewelke et al., 2016; Keesstra et al., 2016; Jiménez-Morillo et al., 2016). The inspiring research of Leonard DeBano and Stefan H Doerr changed the fate of the science (DeBano, 2000; Doerr et al. 2000). Soil water repellency was associated to forest fire affected land due to the pioneer contribution of professor DeBano in the 70's and Professor Doerr in the 90's. The research during the last two decades demonstrate that fire affects the reallocation of the hydrophobic substances and can reduce or increase the severity of the soil water repellence at different soil depths and horizons. The SWR is usually measured by sampling to show the influence of key soil properties (texture, structure, plant cover, litter, season…) on the degree of soil water repellency. The sampling is applied usually with a few drops when the Water Drop Penetration Time method is applied, and this inform of the time of penetration, but few researches focussed in the spatial distribution of the water repellency, which is a key factor of the runoff generation, the water infiltration and the water redistribution such as demonstrate the wetting fronts. Our approach research the spatial distribution of the water repellency by means of an intense sampling of soil surface water repellency. One thousand drops were distributed in a square meter (100 lines separated 1 cm and 100 drops per each line of 100 cm, with a total od 1000 drops in 1m2) on 10 sampling points on 4 land managements: ploughing and herbicide agriculture fields treatment), abandoned 10 years, and burnt. The research was carried out in citrus plantations of the Canyoles river watershed. The results show that the

  17. An adaptive watershed management assessment based on watershed investigation data.

    Science.gov (United States)

    Kang, Min Goo; Park, Seung Woo

    2015-05-01

    The aim of this study was to assess the states of watersheds in South Korea and to formulate new measures to improve identified inadequacies. The study focused on the watersheds of the Han River basin and adopted an adaptive watershed management framework. Using data collected during watershed investigation projects, we analyzed the management context of the study basin and identified weaknesses in water use management, flood management, and environmental and ecosystems management in the watersheds. In addition, we conducted an interview survey to obtain experts' opinions on the possible management of watersheds in the future. The results of the assessment show that effective management of the Han River basin requires adaptive watershed management, which includes stakeholders' participation and social learning. Urbanization was the key variable in watershed management of the study basin. The results provide strong guidance for future watershed management and suggest that nonstructural measures are preferred to improve the states of the watersheds and that consistent implementation of the measures can lead to successful watershed management. The results also reveal that governance is essential for adaptive watershed management in the study basin. A special ordinance is necessary to establish governance and aid social learning. Based on the findings, a management process is proposed to support new watershed management practices. The results will be of use to policy makers and practitioners who can implement the measures recommended here in the early stages of adaptive watershed management in the Han River basin. The measures can also be applied to other river basins.

  18. The Environmental Protection Agency's Watershed-based Approach: where social and natural sciences meet to address today's water resource challenges

    Science.gov (United States)

    Biddle, J. C.

    2010-12-01

    A growing number of governmental organizations at the local, state, and federal level collaborate with nongovernmental organizations and individuals to solve watershed scale problems (Imperial and Koontz, 2007). Such a shift in policy approach from hierarchical regulation to bottom-up collaboration is largely a result of regulator’s recognition of the interdependence of natural and socio-economic systems on a watershed scale (Steelman and Carmin, 2002. Agencies throughout the federal government increasingly favored new governing institutions that encourage cooperation between local actors with conflicting interests, divergent geographic bases, and overlapping administrative jurisdictions to resolve continuing disputes over resource management (Bardach 1998). This favoritism of collaborative over command-and-control approaches for managing nonpoint source pollution led to the development of watershed partnerships and the watershed-based approach (Lubell et al., 2002). This study aims to further collaborative governance scholarship and aid decision-makers in identifying the critical elements of collaborative governance resulting in environmental improvements. To date, this relationship has not been empirically determined, in spite of the fact that collaborative governance is used routinely by the U.S. Environmental Protection Agency in resolving issues related to watershed management and other applications. This gap in the research is largely due to the lack of longitudinal data. In order to determine whether changes have occurred, environmental data must be collected over relatively long time periods (Koontz and Thomas, 2006; Sabatier, et al., 2005). However, collecting these data is often cost prohibitive. Monitoring water quality is expensive and requires technical expertise, and is often the first line item cut in environmental management budgets. This research is interdisciplinary, looking at the physical, chemical, and biological parameters for 44 waterbodies

  19. Annual hydrologic data summary for the White Oak Creek Watershed: Water Year 1990 (October 1989--September 1990)

    Energy Technology Data Exchange (ETDEWEB)

    Borders, D.M.; Gregory, S.M.; Clapp, R.B.; Frederick, B.J.; Moore, G.K.; Watts, J.A.; Broders, C.C.; Bednarek, A.T.

    1991-09-01

    This report summarizes, for the Water Year 1990 (October 1989-- September 1990), the dynamic hydrologic data collected on the Whiteoak Creek (WOC) Watershed's surface and subsurface flow systems. These systems affect the quality or quantity of surface water and groundwater. The collection of hydrologic data is one component of numerous, ongoing Oak Ridge National Laboratory (ORNL) environmental studies and monitoring programs and is intended to 1. characterize the quantity and quality of water in the flow system, 2. plan and assess remedial action activities, and 3. provide long-term availability of data and assure quality. Characterizing the hydrology of the WOC watershed provides a better understanding of the processes which drive contaminant transport in the watershed. Identifying of spatial and temporal trends in hydrologic parameters and mechanisms that affect the movement of contaminants supports the development of interim corrective measures and remedial restoration alternatives. Hydrologic monitoring supports long-term assessment of the effectiveness of remedial actions in limiting the transport of contaminants across Waste Area Grouping boundaries and ultimately to the off-site environment. The majority of the data summarized in this report are available from the Remedial Action Programs Data and Information Management System data base. Surface water data available within the WOC flow system include discharge and runoff, surface water quality, radiological and chemical contamination of sediments, and descriptions of the outfalls to the WOC flow system. Climatological data available for the Oak Ridge area include precipitation, temperature, humidity, wind speed, and wind direction. Information on groundwater levels, aquifer characteristics, and groundwater quality are presented. Anomalies in the data and problems with monitoring and accuracy are discussed. 58 refs., 54 figs., 15 tabs.

  20. Using Dual Isotopes and a Bayesian Isotope Mixing Model to Evaluate Nitrate Sources of Surface Water in a Drinking Water Source Watershed, East China

    Directory of Open Access Journals (Sweden)

    Meng Wang

    2016-08-01

    Full Text Available A high concentration of nitrate (NO3− in surface water threatens aquatic systems and human health. Revealing nitrate characteristics and identifying its sources are fundamental to making effective water management strategies. However, nitrate sources in multi-tributaries and mix land use watersheds remain unclear. In this study, based on 20 surface water sampling sites for more than two years’ monitoring from April 2012 to December 2014, water chemical and dual isotopic approaches (δ15N-NO3− and δ18O-NO3− were integrated for the first time to evaluate nitrate characteristics and sources in the Huashan watershed, Jianghuai hilly region, China. Nitrate-nitrogen concentrations (ranging from 0.02 to 8.57 mg/L were spatially heterogeneous that were influenced by hydrogeological and land use conditions. Proportional contributions of five potential nitrate sources (i.e., precipitation; manure and sewage, M & S; soil nitrogen, NS; nitrate fertilizer; nitrate derived from ammonia fertilizer and rainfall were estimated by using a Bayesian isotope mixing model. The results showed that nitrate sources contributions varied significantly among different rainfall conditions and land use types. As for the whole watershed, M & S (manure and sewage and NS (soil nitrogen were major nitrate sources in both wet and dry seasons (from 28% to 36% for manure and sewage and from 24% to 27% for soil nitrogen, respectively. Overall, combining a dual isotopes method with a Bayesian isotope mixing model offered a useful and practical way to qualitatively analyze nitrate sources and transformations as well as quantitatively estimate the contributions of potential nitrate sources in drinking water source watersheds, Jianghuai hilly region, eastern China.

  1. Does the spatial arrangement of disturbance within forested watersheds affect loadings of nitrogen to stream waters? A test using Landsat and synoptic stream water data

    Science.gov (United States)

    Cowles, Travis R.; McNeil, Brenden E.; Eshleman, Keith N.; Deel, Lindsay N.; Townsend, Philip A.

    2014-02-01

    Remotely sensed maps of forest disturbance provide a powerful tool for predicting spatial and temporal variability in the loading of nitrogen to receiving waters, key data needed for effective watershed management of nutrient pollution. We hypothesize that the spatial arrangement of disturbances within small-forested watersheds can affect N loadings. To test this, we developed schemes for spatially weighting maps of yearly disturbance produced through change analysis of the Landsat Tasseled Cap Disturbance Index (DI), and evaluated the ability of each scheme to predict N concentrations, and subsequently estimated N loads, from forty low-order streams within the Savage River drainage of western Maryland, USA during the 2006-2010 water years, a period encompassing extensive defoliations by gypsy moths (Lymantria dispar). We generated a base scheme of unweighted, watershed averaged change in DI (ΔDI), and five other schemes that weighted ΔDI by either a pixel's flow accumulation value, the distance to the watershed outlet, or proximity to the stream. Over the five years, the flow accumulation scheme tended to perform better than other weighting schemes, and even explained slightly more variability than the base scheme during years of moderate N loads (R2 = 0.15 vs. 0.03 in 2007 and R2 = 0.30 vs. 0.18 in 2010). However, this best spatial weighting scheme explained comparable or less variability during the two post-defoliation years with larger N loads (R2 = 0.43 vs. 0.44 in 2008 and R2 = 0.31 vs. 0.48 in 2009). Thus, for the purposes of utilizing remote sensing information within watershed management of nutrient pollution, these results suggest that coarse-scale, high temporal frequency data such as MODIS could be well suited for characterizing forest disturbance and predicting the resultant episodic N loads.

  2. Adaptive management of rangeland systems

    Science.gov (United States)

    Allen, Craig R.; Angeler, David G.; Fontaine, Joseph J.; Garmestani, Ahjond S.; Hart, Noelle M.; Pope, Kevin L.; Twidwell, Dirac

    2017-01-01

    Adaptive management is an approach to natural resource management that uses structured learning to reduce uncertainties for the improvement of management over time. The origins of adaptive management are linked to ideas of resilience theory and complex systems. Rangeland management is particularly well suited for the application of adaptive management, having sufficient controllability and reducible uncertainties. Adaptive management applies the tools of structured decision making and requires monitoring, evaluation, and adjustment of management. Adaptive governance, involving sharing of power and knowledge among relevant stakeholders, is often required to address conflict situations. Natural resource laws and regulations can present a barrier to adaptive management when requirements for legal certainty are met with environmental uncertainty. However, adaptive management is possible, as illustrated by two cases presented in this chapter. Despite challenges and limitations, when applied appropriately adaptive management leads to improved management through structured learning, and rangeland management is an area in which adaptive management shows promise and should be further explored.

  3. Rare birds for fuzzy jobs: A new type of water professional at the watershed scale in France

    Science.gov (United States)

    Richard-Ferroudji, Audrey

    2014-11-01

    This paper documents changes in the field of water management in France, through the analyses of the activities of water professionals. Hydro-territory professionals work for local authorities in charge of water management at the watershed scale. Their functions appear to be fuzzy. Yet, this paper assumes that this fuzziness is a crucial feature as it manifests an ability to deal with "wicked" problems. Based on quantitative and qualitative inquiries, this paper discusses to what extent these new kind of professionals present themselves as, or differentiate themselves from, experts, facilitators or policy entrepreneurs. It contributes to the studies that highlight the new water professional as a transdisciplinary engineer capable of dealing with negotiation, cooperation or communication issues. Yet, the main result of our study is to show the embedded dimension of hydro-territory professionals, considering water governance as a long term issue of adjustment, assembling, fitting, in a territory and across scales.

  4. Influence of watershed topographic and socio-economic attributes on the climate sensitivity of global river water quality

    Science.gov (United States)

    Khan, Afed U.; Jiang, Jiping; Wang, Peng; Zheng, Yi

    2017-10-01

    Surface waters exhibit regionalization due to various climatic conditions and anthropogenic activities. Here we assess the impact of topographic and socio-economic factors on the climate sensitivity of surface water quality, estimated using an elasticity approach (climate elasticity of water quality (CEWQ)), and identify potential risks of instability in different regions and climatic conditions. Large global datasets were used for 12 main water quality parameters from 43 water quality monitoring stations located at large major rivers. The results demonstrated that precipitation elasticity shows higher sensitivity to topographic and socio-economic determinants as compared to temperature elasticity. In tropical climate class (A), gross domestic product (GDP) played an important role in stabilizing the CEWQ. In temperate climate class (C), GDP played the same role in stability, while the runoff coefficient, slope, and population density fuelled the risk of instability. The results implied that watersheds with lower runoff coefficient, thick population density, over fertilization and manure application face a higher risk of instability. We discuss the socio-economic and topographic factors that cause instability of CEWQ parameters and conclude with some suggestions for watershed managers to bring sustainability in freshwater bodies.

  5. A Stochastic Multi-Objective Chance-Constrained Programming Model for Water Supply Management in Xiaoqing River Watershed

    Directory of Open Access Journals (Sweden)

    Ye Xu

    2017-05-01

    Full Text Available In this paper, a stochastic multi-objective chance-constrained programming model (SMOCCP was developed for tackling the water supply management problem. Two objectives were included in this model, which are the minimization of leakage loss amounts and total system cost, respectively. The traditional SCCP model required the random variables to be expressed in the normal distributions, although their statistical characteristics were suitably reflected by other forms. The SMOCCP model allows the random variables to be expressed in log-normal distributions, rather than general normal form. Possible solution deviation caused by irrational parameter assumption was avoided and the feasibility and accuracy of generated solutions were ensured. The water supply system in the Xiaoqing River watershed was used as a study case for demonstration. Under the context of various weight combinations and probabilistic levels, many types of solutions are obtained, which are expressed as a series of transferred amounts from water sources to treated plants, from treated plants to reservoirs, as well as from reservoirs to tributaries. It is concluded that the SMOCCP model could reflect the sketch of the studied region and generate desired water supply schemes under complex uncertainties. The successful application of the proposed model is expected to be a good example for water resource management in other watersheds.

  6. People and water: Exploring the social-ecological condition of watersheds of the United States

    Directory of Open Access Journals (Sweden)

    Murray W. Scown

    2017-11-01

    Full Text Available A recent paradigm shift from purely biophysical towards social-ecological assessment of watersheds has been proposed to understand, monitor, and manipulate the myriad interactions between human well-being and the ecosystem services that watersheds provide. However, large-scale, quantitative studies in this endeavour remain limited. We utilised two newly developed ‘big-data’ sets—the Index of Watershed Integrity (IWI and the Human Well-Being Index (HWBI—to explore the social-ecological condition of watersheds throughout the conterminous U.S., and identified environmental and socio-economic influences on watershed integrity and human well-being. Mean county IWI was highly associated with ecoregion, industry-dependence, and state, in a spatially-explicit regression model (R2 = 0.77, 'P' < 0.001, whereas HWBI was not (R2 = 0.31, 'P' < 0.001. HWBI is likely influenced by factors not explored here, such as governance structure and formal and informal organisations and institutions. ‘Win-win’ situations in which both IWI and HWBI were above the 75th percentile were observed in much of Utah, Colorado, and New Hampshire, and lessons from governance that has resulted in desirable outcomes might be learnt from here. Eastern Kentucky and West Virginia, along with large parts of the desert southwest, had intact watersheds but low HWBI, representing areas worthy of further investigation of how ecosystem services might be utilised to improve well-being. The Temperate Prairies and Central USA Plains had widespread areas of low IWI but high HWBI, likely a result of historic exploitation of watershed resources to improve well-being, particularly in farming-dependent counties. The lower Mississippi Valley had low IWI and HWBI, which is likely related to historical (temporal and upstream (spatial impacts on both watershed integrity and well-being. The results emphasise the importance of considering spatial and temporal trade-offs when utilising the

  7. Simulated effects of hydrologic, water quality, and land-use changes of the Lake Maumelle watershed, Arkansas, 2004–10

    Science.gov (United States)

    Hart, Rheannon M.; Green, W. Reed; Westerman, Drew A.; Petersen, James C.; DeLanois, Jeanne L.

    2012-01-01

    Lake Maumelle, located in central Arkansas northwest of the cities of Little Rock and North Little Rock, is one of two principal drinking-water supplies for the Little Rock, and North Little Rock, Arkansas, metropolitan areas. Lake Maumelle and the Maumelle River (its primary tributary) are more pristine than most other reservoirs and streams in the region with 80 percent of the land area in the entire watershed being forested. However, as the Lake Maumelle watershed becomes increasingly more urbanized and timber harvesting becomes more extensive, concerns about the sustainability of the quality of the water supply also have increased. Two hydrodynamic and water-quality models were developed to examine the hydrology and water quality in the Lake Maumelle watershed and changes that might occur as the watershed becomes more urbanized and timber harvesting becomes more extensive. A Hydrologic Simulation Program–FORTRAN watershed model was developed using continuous streamflow and discreet suspended-sediment and water-quality data collected from January 2004 through 2010. A CE–QUAL–W2 model was developed to simulate reservoir hydrodynamics and selected water-quality characteristics using the simulated output from the Hydrologic Simulation Program–FORTRAN model from January 2004 through 2010. The calibrated Hydrologic Simulation Program–FORTRAN model and the calibrated CE–QUAL–W2 model were developed to simulate three land-use scenarios and to examine the potential effects of these land-use changes, as defined in the model, on the water quality of Lake Maumelle during the 2004 through 2010 simulation period. These scenarios included a scenario that simulated conversion of most land in the watershed to forest (scenario 1), a scenario that simulated conversion of potentially developable land to low-intensity urban land use in part of the watershed (scenario 2), and a scenario that simulated timber harvest in part of the watershed (scenario 3). Simulated land

  8. Earth observation for rangeland monitoring

    CSIR Research Space (South Africa)

    Ramoelo, Abel

    2012-10-01

    Full Text Available for the methodology is presented in Figure 1. Figure 1: Conceptual framework for the development of grass nutrient estimation models, using remote sensing at various scales Earth Observation for Rangeland Monitoring DR A RAMOELO, DR M CHO AND DR R MATHIEU CSIR... and canopy N conforms to the underlying geology (Figure 2). ACKNOWLEDGEMENT The authors would like to thank the Department of Science and Technology which contributed financially to this work through the grant ?Earth Observation Application Development...

  9. A GIS based watershed information system for water resources management and planning in semi-arid areas

    Science.gov (United States)

    Tzabiras, John; Spiliotopoulos, Marios; Kokkinos, Kostantinos; Fafoutis, Chrysostomos; Sidiropoulos, Pantelis; Vasiliades, Lampros; Papaioannou, George; Loukas, Athanasios; Mylopoulos, Nikitas

    2015-04-01

    The overall objective of this work is the development of an Information System which could be used by stakeholders for the purposes of water management as well as for planning and strategic decision-making in semi-arid areas. An integrated modeling system has been developed and applied to evaluate the sustainability of water resources management strategies in Lake Karla watershed, Greece. The modeling system, developed in the framework of "HYDROMENTOR" research project, is based on a GIS modelling approach which uses remote sensing data and includes coupled models for the simulation of surface water and groundwater resources, the operation of hydrotechnical projects (reservoir operation and irrigation works) and the estimation of water demands at several spatial scales. Lake Karla basin was the region where the system was tested but the methodology may be the basis for future analysis elsewhere. Τwo (2) base and three (3) management scenarios were investigated. In total, eight (8) water management scenarios were evaluated: i) Base scenario without operation of the reservoir and the designed Lake Karla district irrigation network (actual situation) • Reduction of channel losses • Alteration of irrigation methods • Introduction of greenhouse cultivation ii) Base scenario including the operation of the reservoir and the Lake Karla district irrigation network • Reduction of channel losses • Alteration of irrigation methods • Introduction of greenhouse cultivation The results show that, under the existing water resources management, the water deficit of Lake Karla watershed is very large. However, the operation of the reservoir and the cooperative Lake Karla district irrigation network coupled with water demand management measures, like reduction of water distribution system losses and alteration of irrigation methods, could alleviate the problem and lead to sustainable and ecological use of water resources in the study area. Acknowledgements: This study

  10. New insight into the correlations between land use and water quality in a coastal watershed of China: Does point source pollution weaken it?

    Science.gov (United States)

    Zhou, Pei; Huang, Jinliang; Pontius, Robert Gilmore; Hong, Huasheng

    2016-02-01

    Uncovering the associations between land use and river water quality is useful for managing land-based pollution in the catchment-coast continuum. However, it is not clear how land use affects water quality in the context of simultaneous point source (PS) pollution. In this study, we develop a self-organizing map (SOM)-based approach to explore the relationship between land use and water quality in the Minjiang River Watershed, Southeast China. Water samples from 139 headwater sub-watersheds were associated with six land use categories, namely, Woodland, Agriculture, Orchard, Built-up, Unused land and Water. Sampling sites are delineated into six clusters based on six water quality parameters: ammonium-N, nitrate-N, total nitrogen, soluble reactive phosphate, total phosphate and potassium permanganate index. Local relationships between land use and water quality among four clusters that have sufficient sample sizes are further identified. There is no significant land use-water quality correlation in one of the four clusters (including 37 sub-watersheds). And the greater the PS pollution is, the less significant the land use-water quality correlations are in clusters. The results demonstrate how PS pollution weakens the land use-water quality correlation. Our method can help to determine whether non-point source or PS pollution exerts greater influence on the quality of the water coming from watershed. Copyright © 2015 Elsevier B.V. All rights reserved.

  11. Response of Water Resources to Climate and Land-Cover Changes in a Semi-Arid Watershed, New Mexico, USA

    Science.gov (United States)

    Heo, J.

    2016-12-01

    This research evaluates an interconnected system of climate-land cover-water resources in a semi-arid watershed with minimal human impact from 1970 to 2009. We found 0.9°C increase in temperature and 10.9% decrease in precipitation. Temperature had a lower increase trend, and precipitation showed a similar decrease trend, compared to previous studies. The dominant trend of land-cover change was conversion of grass and forest to bush/shrub, and developed land and crop land to barren and grass. These alterations indicate that changes in temperature and precipitation in the study area may be linked to changes in land cover, although human intervention is recognized as the major land-cover change contributor for the short term. These alterations also suggest that decreasing human activity in the study area leads to the conversion of developed land and crop land to barren and grass. Hydrologic responses to climate and land-cover changes for surface runoff, groundwater discharge, soil water content, and evapotranspiration decreased by 10.2, 10.0, 4.1 and 10.5%, respectively. Hydrologic parameters generally follow similar trends to that of precipitation in semi-arid watersheds with minimal human development. Soil water content is sensitive to land-cover change and relatively offset by the changes in precipitation. Citation: Heo, J., J. Yu, J. R. Giardino, and H. Cho (2015), Water resources responses to climate and land-cover changes in a semi-arid watershed, New Mexico, USA, Terr. Atmos. Ocean. Sci., 26, doi: 10.3319/TAO.2015.03.24.01(Hy).

  12. Dynamics and ecological risk assessment of chromophoric dissolved organic matter in the Yinma River Watershed: Rivers, reservoirs, and urban waters.

    Science.gov (United States)

    Li, Sijia; Zhang, Jiquan; Guo, Enliang; Zhang, Feng; Ma, Qiyun; Mu, Guangyi

    2017-10-01

    The extensive use of a geographic information system (GIS) and remote sensing in ecological risk assessment from a spatiotemporal perspective complements ecological environment management. Chromophoric dissolved organic matter (CDOM), which is a complex mixture of organic matter that can be estimated via remote sensing, carries and produces carcinogenic disinfection by-products and organic pollutants in various aquatic environments. This paper reports the first ecological risk assessment, which was conducted in 2016, of CDOM in the Yinma River watershed including riverine waters, reservoir waters, and urban waters. Referring to the risk formation theory of natural disaster, the entropy evaluation method and DPSIR (driving force-pressure-state-impact-response) framework were coupled to establish a hazard and vulnerability index with multisource data, i.e., meteorological, remote sensing, experimental, and socioeconomic data, of this watershed. This ecological vulnerability assessment indicator system contains 23 indicators with respect to ecological sensitivity, ecological pressure, and self-resilience. The characteristics of CDOM absorption parameters from different waters showed higher aromatic content and molecular weights in May because of increased terrestrial inputs. The assessment results indicated that the overall ecosystem risk in the study area was focused in the extremely, heavily, and moderately vulnerable regions. The ecological risk assessment results objectively reflect the regional ecological environment and demonstrate the potential of ecological risk assessment of pollutants over traditional chemical measurements. Copyright © 2017. Published by Elsevier Inc.

  13. Evaluating the Effectiveness of Agricultural Management Practices under Climate Change for Water Quality Improvement in a Rural Agricultural Watershed of Oklahoma, USA

    Science.gov (United States)

    Rasoulzadeh Gharibdousti, S.; Kharel, G.; Stoecker, A.; Storm, D.

    2016-12-01

    One of the main causes of water quality impairment in the United States is human induced Non-Point Source (NPS) pollution through intensive agriculture. Fort Cobb Reservoir (FCR) watershed located in west-central Oklahoma, United States is a rural agricultural catchment with known issues of NPS pollution including suspended solids, siltation, nutrients, and pesticides. The FCR watershed with an area of 813 km2 includes one major lake fed by four tributaries. Recently, several Best Management Practices (BMPs) have been implemented in the watershed (such as no-tillage and cropland to grassland conversion) to improve water quality. In this study we aim to estimate the effectiveness of different BMPs in improving watershed health under future climate projections. We employed the Soil and Water Assessment Tool (SWAT) to develop the hydrological model of the FCR watershed. The watershed was delineated using the 10 m USGS Digital Elevation Model and divided into 43 sub-basins with an average area of 8 km2 (min. 0.2 km2 - max. 28 km2). Through a combination of Soil Survey Geographic Database- SSURGO soil data, the US Department of Agriculture crop layer and the slope information, the watershed was further divided into 1,217 hydrologic response units. The historical climate pattern in the watershed was represented by two different weather stations. The model was calibrated (1991 - 2000) and validated (2001 - 2010) against the monthly USGS observations of streamflow recorded at the watershed outlet using three statistical matrices: coefficient of determination (R2), Nash-Sutcliffe efficiency (NS) and percentage bias (PB). Model parametrization resulted into satisfactory values of R2 (0.56) and NS (0.56) in calibration period and an excellent model performance (R2 = 0.75; NS = 0.75; PB = water and sediment yields under a combination of three Coupled Model Intercomparison Project-5 Global Climate Model projections and two concentration pathways (4.5 and 8.5) downscaled to the

  14. Adaptation to heavy rainfall events: watershed-community planning of soil and water conservation technologies in Syria

    Science.gov (United States)

    Ziadat, Feras; Al-Wadaey, Ahmed; Masri, Zuhair; Sakai, Hirokazu

    2010-05-01

    The Fourth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC) and other research, predict a significant future increase in the frequency and intensity of heavy rainfall events in many regions. This increase runoff and soil erosion, and reduce agricultural productivity, as well as increasing risks of flood damage to crops and infrastructure. Implementing adaptation measures and improved land management through erosion control and soil protection are among those that protect water and agriculture and limit their vulnerability. Soil erosion control practices are often based on long-term climatic averages. Special attention is needed to provide protection against average high-return frequency storms as well as severe storms with low-return frequency. Suitable and affordable soil conservation plans, coupled with an appropriate enabling environment, are needed. A watershed and community were selected in the mountainous area of North West Syria. The fields represent the non-tropical highland dry areas and dominated by olive orchards on steep slopes. Farmers were aware of resource degradation and productivity reduction, but lacked financial capital to implement the needed adaptation measures. A micro-credit system was established with the help of the UNDP Global Environment Facility - Small Grants Program (GEF-SGP) with small grants available for each farmer. Haphazard implementation on scattered fields proved inefficient in demonstrating obvious impact. Therefore, each watershed was classified into three erosion risk categories (high, moderate and low), derived from maps of flow accumulation, slope steepness, slope shape and land use. Using field survey of land ownership, the boundaries of 168 farms in the watersheds were mapped. Farmers' fields were classified using the erosion-risk map and considering the on-farm erosion hazard and the off-farm effect on other farmers' fields following the hillslope sequence. More than 60% of the farms were

  15. Watershed Characteristics and Pre-Restoration Surface-Water Hydrology of Minebank Run, Baltimore County, Maryland, Water Years 2002-04

    Science.gov (United States)

    Doheny, Edward J.; Starsoneck, Roger J.; Striz, Elise A.; Mayer, Paul M.

    2006-01-01

    Stream restoration efforts have been ongoing in Maryland since the early 1990s. Physical stream restoration often involves replacement of lost sediments to elevate degraded streambeds, re-establishment of riffle-pool sequences along the channel profile, planting vegetation in riparian zones, and re-constructing channel banks, point bars, flood plains, and stream-meanders. The primary goal of many restoration efforts is to re-establish geomorphic stability of the stream channel and reduce erosive energy from urban runoff. Monitoring streams prior to and after restoration could help quantify other possible benefits of stream restoration, such as improved water quality and biota. This report presents general watershed characteristics associated with the Minebank Run watershed; a small, urban watershed in the south-central section of Baltimore County, Maryland that was physically restored in phases during 1999, 2004, and 2005. The physiography, geology, hydrology, land use, soils, and pre-restoration geomorphic setting of the unrestored stream channel are discussed. The report describes a reach of Minebank Run that was selected for the purpose of collecting several types of environmental data prior to restoration, including continuous-record and partial-record stage and streamflow data, precipitation, and ground-water levels. Examples of surface-water data that were collected in and near the study reach during water years 2002 through 2004, including continuous-record streamflow, partial-record stage and discharge, and precipitation, are described. These data were used in analyses of several characteristics of surface-water hydrology in the watershed, including (1) rainfall totals, storm duration, and intensity, (2) instantaneous peak discharge and daily mean discharge, (3) stage-discharge ratings, (4) hydraulic-geometry relations, (5) water-surface slope, (6) time of concentration, (7) flood frequency, (8) flood volume, and (9) rainfall-runoff relations. Several

  16. Assessment of pathogen levels in stream water column and bed sediment of Merced River Watershed in California

    Science.gov (United States)

    Vaddella, V. K.; Pandey, P.; Biswas, S.; Lewis, D. J.

    2014-12-01

    Mitigating pathogen levels in surface water is crucial for protecting public health. According to the U.S. Environmental Protection Agency (US EPA), approximately 480,000 km of rivers/streams are contaminated in the U.S., and a major cause of contamination is elevated levels of pathogen/pathogen indicator. Many of past studies showed considerably higher pathogen levels in sediment bed than that of the stream water column in rivers. In order to improve the understanding of pathogen levels in rivers in California, we carried out an extensive pathogen monitoring study in four different watersheds (Bear Creek, Ingalsbe, Maxwell, and Yosemite watersheds) of Merced River. Stream water and streambed sediment samples were collected from 17 locations. Pathogen levels (E. coli O157:H7, Salmonella spp., and Listeria monocytogenes) were enumerated in streambed sediment and water column. In addition, the impacts of heat stress on pathogen survival were assessed by inoculating pathogens into the water and sediment samples for understanding the pathogen survival in stream water column and streambed sediment. The pathogen enumeration (in water column and sediment bed) results indicated that the E. coli O157:H7, Salmonella spp. and Listeria monocytogenes levels were non-detectable in the water column and streambed sediment. The results of heat stress (50◦ C for 180 minutes) test indicated a pathogen decay at one order of magnitude (108 cfu/ml to 107 cfu/ml). Nonetheless, higher pathogen levels (1.13 × 107 cfu/ml) after the heat stress study showed potential pathogen survival at higher temperature. Preliminary results of this study would help in understanding the impacts of elevated temperature on pathogen in stream environment. Further studies are required to test the long-term heat-stress impacts on pathogen survival.

  17. Water-quality data and Escherichia coli predictions for selected karst catchments of the upper Duck River watershed in central Tennessee, 2007–10

    Science.gov (United States)

    Murphy, Jennifer C.; Farmer, James; Layton, Alice

    2016-06-13

    The U.S. Geological Survey, in cooperation with the Tennessee Duck River Development Agency, monitored water quality at several locations in the upper Duck River watershed between October 2007 and September 2010. Discrete water samples collected at 24 sites in the watershed were analyzed for water quality, and Escherichia coli (E. coli) and enterococci concentrations. Additional analyses, including the determination of anthropogenic-organic compounds, bacterial concentration of resuspended sediment, and bacterial-source tracking, were performed at a subset of sites. Continuous monitoring of streamflow, turbidity, and specific conductance was conducted at seven sites; a subset of sites also was monitored for water temperature and dissolved oxygen concentration. Multiple-regression models were developed to predict instantaneous E. coli concentrations and loads at sites with continuous monitoring. This data collection effort, along with the E. coli models and predictions, support analyses of the relations among land use, bacteria source and transport, and basin hydrology in the upper Duck River watershed.

  18. Ground-Water Sources, Flow-Paths, and Residence Times in the Middle Verde River Watershed, Northern Arizona

    Science.gov (United States)

    Zlatos, C. M.; Hogan, J. F.; Blasch, K. W.; Bills, D. J.; Meixner, T.

    2007-12-01

    Geochemical tracers serve as valuable tools for characterizing basin hydrogeology. By combining stable and radioactive isotopic analyses with solute concentrations and discharge data, one can constrain hydrologic flow- paths and water sources in an area of complex hydrogeology. These techniques are applicable to the Middle Verde River watershed, a region located in the transition zone between the Southern Colorado Plateau and the Basin and Range structural provinces. As the population within the Verde River Valley is projected to double by 2050, efforts to improve the conceptual understanding of basin hydrogeology and to quantify recharge rates within the watershed are critical for water resources management. The primary objective of the investigation is to determine the hydrologic connection between aquifers underlying the Colorado Plateau and adjacent aquifers in the Verde River watershed through analysis of oxygen and hydrogen stable isotopes, tritium, carbon-14, and major solute concentrations. The secondary objective is to gain an understanding of how these water sources and flow-paths contribute to and sustain Verde River base-flow. Two surface-water datasets collected from the Middle Verde River and its tributaries (Oak Creek, Wet Beaver Creek, and West Clear Creek) in November 2006 and June 2007 serve as snapshots of winter and summer base-flow conditions, respectively. Ground-water samples complement these datasets by serving as end members for base-flow source mixing models. Preliminary analyses based on solute relationships (i.e. chloride- sulfate and bromide-chloride) show evidence of separate solute sources for the Verde River and its tributaries. The distinct Verde River trends, including overall increases in solute concentrations along two reaches (kilometers 15 to 30 and 57 to 66, as measured upstream from USGS gauge 09506000), suggest dissolution of evaporite deposits within the Tertiary lakebed-derived Verde Formation. Notably, ground-water from

  19. Criteria and indicators for sustainable rangeland management

    Science.gov (United States)

    John E. Mitchell

    2010-01-01

    The concept of sustainable management encompasses ecological, economic, and social criteria and indicators (C&I) for monitoring and assessing the association between maintaining a healthy rangeland base and sustaining the well-being of communities and economies. During a series of meetings from 2001 to 2003, the Sustainable Rangelands Roundtable (SRR) developed...

  20. Remote sensing applications for monitoring rangeland vegetation ...

    African Journals Online (AJOL)

    Remote sensing techniques hold considerable promise for the inventory and monitoring of natural resources on rangelands. A significant lack of information concerning basic spectral characteristics of range vegetation and soils has resulted in a lack of rangeland applications. The parameters of interest for range condition ...

  1. Development of a computerised rangelands resource information ...

    African Journals Online (AJOL)

    Data on livestock inventory, rangelands resources, and status of land degradation were integrated to produce a computerised resource information system for Swaziland, which will assist in decision making for monitoring and management of rangelands resources; its application is demonstrated. The resource information ...

  2. The Vale rangeland rehabilitation program: an evaluation.

    Science.gov (United States)

    Harold F. Heady

    1988-01-01

    This manuscript discusses the initiation, execution, and outcome of an 11-year (1962-1972) rangeland rehabilitation program in southeastern Oregon. Res. Bull. PNW-RB-070 (1977) is updated with 1986 measurements and evaluations of vegetational conditions, wildlife, recreational use, livestock grazing, and management of public rangelands. The mix of multiple uses has...

  3. Current situation of rangelands in Mexico

    Science.gov (United States)

    Alicia Melgoza-Castillo

    2006-01-01

    Rangelands are natural areas with certain characteristics that make them unsuitable for agriculture. They include several types of vegetation such as deserts, grasslands, shrubs, forests, and riparian areas. Cattle ranching, along with the products and services it engenders, is a prime activity that rangelands have traditionally supported.

  4. Tackling 'the most avoided issue\\'*: communal rangeland ...

    African Journals Online (AJOL)

    Facilitator training for communal rangeland management should include social skills, the social context of communal rangelands and novice facilitators should be supported by mentors. There is a need for greater financial support and law enforcement from the state in the area of communal grazing management. Keywords: ...

  5. A Dynamic Model of California's Hardwood Rangelands

    Science.gov (United States)

    Richard B. Standiford; Richard E. Howitt

    1991-01-01

    Low profitability of hardwood rangeland management, and oak tree harvesting for firewood markets and forage enhancement has led to concern about the long-term sustainability of the oak resource on rangelands. New markets for recreational hunting may give value to oaks for the habitat they provide for game species, and broaden the economic base for managers. A ranch...

  6. Applying animal behavior to arid rangeland mangement

    Science.gov (United States)

    Livestock production is one of many demands placed on today’s arid rangelands. Therefore, understanding plant and animal biology and their effects on biotic and abiotic landscape components is fundamental if rangelands are to remain ecologically sustainable. One limiting factor to accomplishing posi...

  7. Achieving Peak Flow and Sediment Loading Reductions through Increased Water Storage in the Le Sueur Watershed, Minnesota: A Modeling Approach

    Science.gov (United States)

    Mitchell, N. A.; Gran, K. B.; Cho, S. J.; Dalzell, B. J.; Kumarasamy, K.

    2015-12-01

    A combination of factors including climate change, land clearing, and artificial drainage have increased many agricultural regions' stream flows and rates at which channel banks and bluffs are eroded. Increasing erosion rates within the Minnesota River Basin have contributed to higher sediment-loading rates, excess turbidity levels, and increases in sedimentation rates in Lake Pepin further downstream. Water storage sites (e.g., wetlands) have been discussed as a means to address these issues. This study uses the Soil and Water Assessment Tool (SWAT) to assess a range of water retention site (WRS) implementation scenarios in the Le Sueur watershed in south-central Minnesota, a subwatershed of the Minnesota River Basin. Sediment loading from bluffs was assessed through an empirical relationship developed from gauging data. Sites were delineated as topographic depressions with specific land uses, minimum areas (3000 m2), and high compound topographic index values. Contributing areas for the WRS were manually measured and used with different site characteristics to create 210 initial WRS scenarios. A generalized relationship between WRS area and contributing area was identified from measurements, and this relationship was used with different site characteristics (e.g., depth, hydraulic conductivity (K), and placement) to create 225 generalized WRS scenarios. Reductions in peak flow volumes and sediment-loading rates are generally maximized by placing site with high K values in the upper half of the watershed. High K values allow sites to lose more water through seepage, emptying their storages between precipitation events and preventing frequent overflowing. Reductions in peak flow volumes and sediment-loading rates also level off at high WRS extents due to the decreasing frequencies of high-magnitude events. The generalized WRS scenarios were also used to create a simplified empirical model capable of generating peak flows and sediment-loading rates from near

  8. Increased water yields following harvesting operations on a drained coastal watershed

    Science.gov (United States)

    Johnny M. Grace; R.W. Skaggs; H.R. Malcom; G.M. Chescheir; D.K. Cassel

    2003-01-01

    Forest harvesting operations have been reported to affect annual and seasonal outflow characteristics from drained forest watersheds. Increases in forest outflow, nutrient concentrations, and suspended sediments are commonly seen as a result of these forest management activities. Thus, it is important to assess the impact of forest management activities on hydrology,...

  9. Integrated research - water quality, sociological, economic, and modeling - in a regulated watershed: Jordan Lake, NC

    Science.gov (United States)

    Deanna Osmond; Mazdak Arabi; Caela O' Connell; Dana Hoag; Dan Line; Marzieh Motallebi; Ali Tasdighi

    2016-01-01

    Jordan Lake watershed is regulated by state rules in order to reduce nutrient loading from point and both agricultural and urban nonpoint sources. The agricultural community is expected to reduce nutrient loading by specific amounts that range from 35 - 0 percent nitrogen, and 5 - 0 percent phosphorus.

  10. Water and watershed management in India: Policy issues and priority areas for future research

    Science.gov (United States)

    Satish Chandra; K. K. S. Bhatia

    2000-01-01

    India's present food requirements of 220 million tonnes will likely increase to 340 million tonnes in 20 years. Expansion in the agriculture sector to meet these demands can be achieved only by devoting greater attention to restoring watershed lands previously degraded by excessive soil erosion to higher productivity and more efficiently utilizing the country...

  11. IMPACTS OF MARINE AEROSOLS ON SURFACE WATER CHEMISTRY AT BEAR BROOK WATERSHED, MAINE USA

    Science.gov (United States)

    The East Bear catchment at Bear Brook Watershed, Maine receives moderate (for the eastern U.S.) amounts of Cl- in wet and dry deposition. In 1989, Cl- in precipitation ranged from 2 to 55 eq/L. Dry, occult, and wet deposition plus evapotranspiration resulted in stream Cl- averagi...

  12. Perfluoroalkyl acids in surface waters and tapwater in the Qiantang River watershed-Influences from paper, textile, and leather industries.

    Science.gov (United States)

    Lu, Guo-Hui; Gai, Nan; Zhang, Peng; Piao, Hai-Tao; Chen, Shu; Wang, Xiao-Chun; Jiao, Xing-Chun; Yin, Xiao-Cai; Tan, Ke-Yan; Yang, Yong-Liang

    2017-10-01

    Perfluoroalkyl acids (PFAAs) are widely used as multi-purpose surfactants or water/oil repellents. In order to understand the contamination level and compositional profiles of PFAAs in aqueous environment in textile, leather, and paper making industrial areas, surface waters and tap waters were collected along the watershed of the Qiantang River where China's largest textile, leather, and paper making industrial bases are located. For comparison, surface water and tapwater samples were also collected in Hangzhou and its adjacent areas. 17 PFAAs were analyzed by solid phase extraction-high performance liquid chromatography-tandem mass spectrometry. The results show that the total concentrations of PFAAs (ΣPFAAs) in the Qiantang River waters ranged from 106.1 to 322.9 ng/L, averaging 164.2 ng/L. The contamination levels have been found to be extremely high, comparable to the levels of the most serious PFAA contamination in surface waters of China. The PFAA composition profiles were characterized by the dominant PFOA (average 58.1% of the total PFAAs), and PFHxA (average 18.8%). The ΣPFAAs in tap water ranged from 9.5 to 174.8 ng/L, showing PFAA compositional pattern similar to the surface waters. Good correlations between PFAA composition profiles in tap waters and the surface waters were observed. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Water Resources Response to Climate and Land-Cover Changes in a Semi-Arid Watershed, New Mexico, USA

    Directory of Open Access Journals (Sweden)

    Joonghyeok Heo

    2015-01-01

    Full Text Available This research evaluates a climate-land cover-water resources interconnected system in a semi-arid watershed with minimal human impact from 1970 - 2009. We found _ increase in temperature and 10.9% decrease in precipitation. The temperature exhibited a lower increase trend and precipitation showed a similar decrease trend compared to previous studies. The dominant land-cover change trend was grass and forest conversion into bush/shrub and developed land and crop land into barren and grass land. These alterations indicate that changes in temperature and precipitation in the study area may be linked to changes in land cover, although human intervention is recognized as the major land-cover change contributor for the short term. These alterations also suggest that decreasing human activity in the study area leads to developed land and crop land conversion into barren and grass land. Hydrological responses to climate and land-cover changes for surface runoff, groundwater discharge, soil water content and evapotranspiration decreased by 10.2, 10.0, 4.1, and 10.5%, respectively. Hydrological parameters generally follow similar trends to that of precipitation in semi-arid watersheds with minimal human development. Soil water content is sensitive to land-cover change and offset relatively by the changes in precipitation.

  14. Multiple-response Bayesian calibration of watershed water quality models with significant input and model structure errors

    Science.gov (United States)

    Han, Feng; Zheng, Yi

    2016-02-01

    While watershed water quality (WWQ) models have been widely used to support water quality management, their profound modeling uncertainty remains an unaddressed issue. Data assimilation via Bayesian calibration is a promising solution to the uncertainty, but has been rarely practiced for WWQ modeling. This study applied multiple-response Bayesian calibration (MRBC) to SWAT, a classic WWQ model, using the nitrate pollution in the Newport Bay Watershed (southern California, USA) as the study case. How typical input and model structure errors would impact modeling uncertainty, parameter identification and management decision-making was systematically investigated through both synthetic and real-situation modeling cases. The main study findings include: (1) with an efficient sampling scheme, MRBC is applicable to WWQ modeling in characterizing its parametric and predictive uncertainties; (2) incorporating hydrology responses, which are less susceptible to input and model structure errors than water quality responses, can improve the Bayesian calibration results and benefit potential modeling-based management decisions; and (3) the value of MRBC to modeling-based decision-making essentially depends on pollution severity, management objective and decision maker's risk tolerance.

  15. Environmental exposure and risk assessment of fluoroquinolone antibacterial agents in wastewater and river water of the Glatt Valley Watershed, Switzerland.

    Science.gov (United States)

    Golet, Eva M; Alder, Alfredo C; Giger, Walter

    2002-09-01

    The mass flows of fluoroquinolone antibacterial agents (FQs) were investigated in the aqueous compartments of the Glatt Valley Watershed, a densely populated region in Switzerland. The major human-use FQs consumed in Switzerland, ciprofloxacin (CIP) and norfloxacin (NOR), were determined in municipal wastewater effluents and in the receiving surface water, the Glatt River. Individual concentrations in raw sewage and in final wastewater effluents ranged from 255 to 568 ng/L and from 36 to 106 ng/L, respectively. In the Glatt River, the FQs were present at concentrations below 19 ng/L. The removal of FQs from the water stream during wastewater treatment was between 79 and 87%. During the studied summer period, FQs in the dissolved fraction were significantly reduced downstream in the Glatt River (15-20 h residence time) (66% for CIP and 48% for NOR). Thus, after wastewater treatment, transport in rivers causes an additional decrease of residual levels of FQs in the aquatic environment. Refined predicted environmental concentrations for the study area compare favorably with the measured environmental concentrations (MEC) obtained in the monitoring study. Total measured FQ concentrations occurring in the examined aquatic compartments of the Glatt Valley Watershed were related to acute ecotoxicity data from the literature. The risk quotients obtained (MEC/PNEC < 1) following the recommendations of the European guidelines or draft documents suggest a low probability for adverse effects of the occurring FQs, either on microbial activity in WWTPs or on algae, daphnia, and fish in surface waters.

  16. The Role of Rangelands in Diversified Farming Systems: Innovations, Obstacles, and Opportunities in the USA

    Directory of Open Access Journals (Sweden)

    Nathan F. Sayre

    2012-12-01

    Full Text Available Discussions of diversified farming systems (DFS rarely mention rangelands: the grasslands, shrublands, and savannas that make up roughly one-third of Earth's ice-free terrestrial area, including some 312 million ha of the United States. Although ranching has been criticized by environmentalists for decades, it is probably the most ecologically sustainable segment of the U.S. meat industry, and it exemplifies many of the defining characteristics of DFS: it relies on the functional diversity of natural ecological processes of plant and animal (reproduction at multiple scales, based on ecosystem services generated and regenerated on site rather than imported, often nonrenewable, inputs. Rangelands also provide other ecosystem services, including watershed, wildlife habitat, recreation, and tourism. Even where non-native or invasive plants have encroached on or replaced native species, rangelands retain unusually high levels of plant diversity compared with croplands or plantation forests. Innovations in management, marketing, incentives, and easement programs that augment ranch income, creative land tenure arrangements, and collaborations among ranchers all support diversification. Some obstacles include rapid landownership turnover, lack of accessible U.S. Department of Agriculture certified processing facilities, tenure uncertainty, fragmentation of rangelands, and low and variable income, especially relative to land costs. Taking advantage of rancher knowledge and stewardship, and aligning incentives with production of diverse goods and services, will support the sustainability of ranching and its associated public benefits. The creation of positive feedbacks between economic and ecological diversity should be the ultimate goal.

  17. Using the Soil and Water Assessment Tool (SWAT) to assess land use impact on water resources in an East African watershed

    Science.gov (United States)

    Baker, Tracy J.; Miller, Scott N.

    2013-04-01

    SummaryLand cover and land use changes in Kenya's Rift Valley have altered the hydrologic response of the River Njoro watershed by changing the partitioning of excess rainfall into surface discharge and groundwater recharge. The watershed contributes a significant amount of water to Lake Nakuru National Park, an internationally recognized Ramsar site, as well as groundwater supplies for local communities and the city of Nakuru. Three land use maps representing a 17-year period when the region underwent significant transitions served as inputs for hydrologic modeling using the Automated Geospatial Watershed Assessment (AGWA) tool, a GIS-based hydrologic modeling system. AGWA was used to parameterize the Soil and Water Assessment Tool (SWAT), a hydrologic model suitable for assessing the relative impact of land cover change on hydrologic response. The SWAT model was calibrated using observation data taken during the 1990s with high annual concordance. Simulation results showed that land use changes have resulted in corresponding increases in surface runoff and decreases in groundwater recharge. Hydrologic changes were highly variable both spatially and temporally, and the uppermost reaches of the forested highlands were most significantly affected. These changes have negative implications for the ecological health of the river system as well as Lake Nakuru and local communities.

  18. River basins as social-ecological systems: linking levels of societal and ecosystem water metabolism in a semiarid watershed

    Directory of Open Access Journals (Sweden)

    Violeta Cabello

    2015-09-01

    Full Text Available River basin modeling under complexity requires analytical frameworks capable of dealing with the multiple scales and dimensions of environmental problems as well as uncertainty in the evolution of social systems. Conceptual and methodological developments can now be framed using the wide socio-eco-hydrological approach. We add hierarchy theory into the mix to discuss the conceptualization of river basins as complex, holarchic social-ecological systems. We operationalize the social-ecological systems water metabolism framework in a semiarid watershed in Spain, and add the governance dimension that shapes human-environment reciprocity. To this purpose, we integrate an eco-hydrological model with the societal metabolism accounting scheme for land use, human activity, and water use. We explore four types of interactions: between societal organization and water uses/demands, between ecosystem organization and their water requirements/supplies, between societal metabolism and aquatic ecosystem health, and between water demand and availability. Our results reveal a metabolic pattern of a high mountain rural system striving to face exodus and agricultural land abandonment with a multifunctional economy. Centuries of social-ecological evolution shaping waterscapes through traditional water management practices have influenced the eco-hydrological functioning of the basin, enabling adaptation to aridity. We found a marked spatial gradient on water supply, use pattern, and impact on water bodies from the head to the mouth of the basin. Management challenges posed by the European water regulatory framework as a new driver of social-ecological change are highlighted.

  19. Resource management in rangeland

    Science.gov (United States)

    Adequate assessments of vast expanses of rangeland—a primary prerequisite to effective conservation planning—requires landscape-scale evaluations that accurately represent the resources (e.g., soil, vegetation, wildlife, water ), the structure and function of the resource-providing systems, and the ...

  20. Evaluating the effectiveness of management practices on hydrology and water quality at watershed scale with a rainfall-runoff model.

    Science.gov (United States)

    Liu, Yaoze; Bralts, Vincent F; Engel, Bernard A

    2015-04-01

    The adverse influence of urban development on hydrology and water quality can be reduced by applying best management practices (BMPs) and low impact development (LID) practices. This study applied green roof, rain barrel/cistern, bioretention system, porous pavement, permeable patio, grass strip, grassed swale, wetland channel, retention pond, detention basin, and wetland basin, on Crooked Creek watershed. The model was calibrated and validated for annual runoff volume. A framework for simulating BMPs and LID practices at watershed scales was created, and the impacts of BMPs and LID practices on water quantity and water quality were evaluated with the Long-Term Hydrologic Impact Assessment-Low Impact Development 2.1 (L-THIA-LID 2.1) model for 16 scenarios. The various levels and combinations of BMPs/LID practices reduced runoff volume by 0 to 26.47%, Total Nitrogen (TN) by 0.30 to 34.20%, Total Phosphorus (TP) by 0.27 to 47.41%, Total Suspended Solids (TSS) by 0.33 to 53.59%, Lead (Pb) by 0.30 to 60.98%, Biochemical Oxygen Demand (BOD) by 0 to 26.70%, and Chemical Oxygen Demand (COD) by 0 to 27.52%. The implementation of grass strips in 25% of the watershed where this practice could be applied was the most cost-efficient scenario, with cost per unit reduction of $1m3/yr for runoff, while cost for reductions of two pollutants of concern was $445 kg/yr for Total Nitrogen (TN) and $4871 kg/yr for Total Phosphorous (TP). The scenario with very high levels of BMP and LID practice adoption (scenario 15) reduced runoff volume and pollutant loads from 26.47% to 60.98%, and provided the greatest reduction in runoff volume and pollutant loads among all scenarios. However, this scenario was not as cost-efficient as most other scenarios. The L-THIA-LID 2.1 model is a valid tool that can be applied to various locations to help identify cost effective BMP/LID practice plans at watershed scales. Copyright © 2014 Elsevier B.V. All rights reserved.

  1. Green Infrastructure Design for Stormwater Runoff and Water Quality: Empirical Evidence from Large Watershed-Scale Community Developments

    Directory of Open Access Journals (Sweden)

    Bo Yang

    2013-12-01

    Full Text Available Green infrastructure (GI design is advocated as a new paradigm for stormwater management, whereas current knowledge of GI design is mostly based on isolated design strategies used at small-scale sites. This study presents empirical findings from two watershed-scale community projects (89.4 km2 and 55.7 km2 in suburban Houston, Texas. The GI development integrates a suite of on-site, infiltration-based stormwater management designs, and an adjacent community development follows conventional drainage design. Parcel data were used to estimate the site impervious cover area. Observed streamflow and water quality data (i.e., NO3-N, NH3-N, and TP were correlated with the site imperviousness. Results show that, as of 2009, the impervious cover percentage in the GI site (32.3% is more than twice that of the conventional site (13.7%. However, the GI site’s precipitation-streamflow ratio maintains a steady, low range, whereas this ratio fluctuates substantially in the conventional site, suggesting a “flashy” stream condition. Furthermore, in the conventional site, annual nutrient loadings are significantly correlated with its impervious cover percentage (p < 0.01, whereas in the GI site there is little correlation. The study concludes that integrated GI design can be effective in stormwater runoff reduction and water quality enhancement at watershed-scale community development.

  2. A review of concentrated flow erosion processes on rangelands: Fundamental understanding and knowledge gaps

    Directory of Open Access Journals (Sweden)

    Sayjro K. Nouwakpo

    2016-06-01

    Full Text Available Concentrated flow erosion processes are distinguished from splash and sheetflow processes in their enhanced ability to mobilize and transport large amounts of soil, water and dissolved elements. On rangelands, soil, nutrients and water are scarce and only narrow margins of resource losses are tolerable before crossing the sustainability threshold. In these ecosystems, concentrated flow processes are perceived as indicators of degradation and often warrant the implementation of mitigation strategies. Nevertheless, this negative perception of concentrated flow processes may conflict with the need to improve understanding of the role of these transport vessels in redistributing water, soil and nutrients along the rangeland hillslope. Vegetation influences the development and erosion of concentrated flowpaths and has been the primary factor used to control and mitigate erosion on rangelands. At the ecohydrologic level, vegetation and concentrated flow pathways are engaged in a feedback relationship, the understanding of which might help improve rangeland management and restoration strategies. In this paper, we review published literature on experimental and conceptual research pertaining to concentrated flow processes on rangelands to: (1 present the fundamental science underpinning concentrated flow erosion modeling in these landscapes, (2 discuss the influence of vegetation on these erosion processes, (3 evaluate the contribution of concentrated flow erosion to overall sediment budget and (4 identify knowledge gaps.

  3. Watershed Dynamics, with focus on connectivity index and management of water related impacts on road infrastructure

    Science.gov (United States)

    Kalantari, Z.

    2015-12-01

    In Sweden, spatially explicit approaches have been applied in various disciplines such as landslide modelling based on soil type data and flood risk modelling for large rivers. Regarding flood mapping, most previous studies have focused on complex hydrological modelling on a small scale whereas just a few studies have used a robust GIS-based approach integrating most physical catchment descriptor (PCD) aspects on a larger scale. This study was built on a conceptual framework for looking at SedInConnect model, topography, land use, soil data and other PCDs and climate change in an integrated way to pave the way for more integrated policy making. The aim of the present study was to develop methodology for predicting the spatial probability of flooding on a general large scale. This framework can provide a region with an effective tool to inform a broad range of watershed planning activities within a region. Regional planners, decision-makers, etc. can utilize this tool to identify the most vulnerable points in a watershed and along roads to plan for interventions and actions to alter impacts of high flows and other extreme weather events on roads construction. The application of the model over a large scale can give a realistic spatial characterization of sediment connectivity for the optimal management of debris flow to road structures. The ability of the model to capture flooding probability was determined for different watersheds in central Sweden. Using data from this initial investigation, a method to subtract spatial data for multiple catchments and to produce soft data for statistical analysis was developed. It allowed flood probability to be predicted from spatially sparse data without compromising the significant hydrological features on the landscape. This in turn allowed objective quantification of the probability of floods at the field scale for future model development and watershed management.

  4. Multiple Time-Scale Monitoring to Address Dynamic Seasonality and Storm Pulses of Stream Water Quality in Mountainous Watersheds

    Directory of Open Access Journals (Sweden)

    Hyun-Ju Lee

    2015-11-01

    Full Text Available Rainfall variability and extreme events can amplify the seasonality and storm pulses of stream water chemistry in mountainous watersheds under monsoon climates. To establish a monitoring program optimized for identifying potential risks to stream water quality arising from rainfall variability and extremes, we examined water chemistry data collected on different timescales. At a small forested watershed, bi-weekly sampling lasted over two years, in comparison to three other biweekly sampling sites. In addition, high-frequency continuous measurements of pH, electrical conductivity, and turbidity were conducted in tandem with automatic water sampling at 2 h intervals during eight rainfall events. Biweekly monitoring showed that during the summer monsoon period, electrical conductivity (EC, dissolved oxygen (DO, and dissolved ion concentrations generally decreased, but total suspended solids (TSS slightly increased. A noticeable variation from the usual seasonal pattern was that DO levels substantially decreased during an extended drought. Bi-hourly storm event samplings exhibited large changes in the concentrations of TSS and particulate and dissolved organic carbon (POC; DOC during intense rainfall events. However, extreme fluctuations in sediment export during discharge peaks could be detected only by turbidity measurements at 5 min intervals. Concomitant measurements during rainfall events established empirical relationships between turbidity and TSS or POC. These results suggest that routine monitoring based on weekly to monthly sampling is valid only in addressing general seasonal patterns or long-lasting phenomena such as drought effects. We propose an “adaptive” monitoring scheme that combines routine monitoring for general seasonal patterns and high-frequency instrumental measurements of water quality components exhibiting rapid responses pulsing during intense rainfall events.

  5. Occurrence of pesticides in surface water and sediments from three central California coastal watersheds, 2008-2009

    Science.gov (United States)

    Smalling, Kelly L.; Orlando, James L.

    2011-01-01

    Water and sediment (bed and suspended) were collected from January 2008 through October 2009 from 12 sites in 3 of the largest watersheds along California's Central Coast (Pajaro, Salinas, and Santa Maria Rivers) and analyzed for a suite of pesticides by the U.S. Geological Survey. Water samples were collected in each watershed from the estuaries and major tributaries during 4 storm events and 11 dry season sampling events in 2008 and 2009. Bed sediments were collected from depositional zones at the tributary sampling sites three times over the course of the study. Suspended sediment samples were collected from the major tributaries during the four storm events and in the tributaries and estuaries during three dry season sampling events in 2009. Water samples were analyzed for 68 pesticides using gas chromatography/mass spectrometry. A total of 38 pesticides were detected in 144 water samples, and 13 pesticides were detected in more than half the samples collected over the course of the study. Dissolved pesticide concentrations ranged from below their method detection limits to 36,000 nanograms per liter (boscalid). The most frequently detected pesticides in water from all the watersheds were azoxystrobin, boscalid, chlorpyrifos, DCPA, diazinon, oxyfluorfen, prometryn, and propyzamide, which were found in more than 80 percent of the samples. On average, detection frequencies and concentrations were higher in samples collected during winter storm events compared to the summer dry season. With the exception of the fungicide, myclobutanil, the Santa Maria estuary watershed exhibited higher pesticide detection frequencies than the Pajaro and Salinas watersheds. Bed and suspended sediment samples were analyzed for 55 pesticides using accelerated solvent extraction, gel permeation chromatography for sulfur removal, and carbon/alumina stacked solid-phase extraction cartridges to remove interfering sediment matrices. In bed sediment samples, 17 pesticides were detected

  6. Influence of hydrological conditions on the Escherichia coli population structure in the water of a creek on a rural watershed

    Directory of Open Access Journals (Sweden)

    Ratajczak Mehdy

    2010-08-01

    Full Text Available Abstract Background Escherichia coli is a commensal bacterium of the gastro-intestinal tract of human and vertebrate animals, although the aquatic environment could be a secondary habitat. The aim of this study was to investigate the effect of hydrological conditions on the structure of the E. coli population in the water of a creek on a small rural watershed in France composed of pasture and with human occupation. Results It became apparent, after studying the distribution in the four main E. coli phylo-groups (A, B1, B2, D, the presence of the hly (hemolysin gene and the antibiotic resistance pattern, that the E. coli population structure was modified not only by the hydrological conditions (dry versus wet periods, rainfall events, but also by how the watershed was used (presence or absence of cattle. Isolates of the B1 phylo-group devoid of hly and sensitive to antibiotics were particularly abundant during the dry period. During the wet period and the rainfall events, contamination from human sources was predominantly characterized by strains of the A phylo-group, whereas contamination by cattle mainly involved B1 phylo-group strains resistant to antibiotics and exhibiting hly. As E. coli B1 was the main phylo-group isolated in water, the diversity of 112 E. coli B1 isolates was further investigated by studying uidA alleles (beta-D-glucuronidase, the presence of hly, the O-type, and antibiotic resistance. Among the forty epidemiolgical types (ETs identified, five E. coli B1 ETs were more abundant in slightly contaminated water. Conclusions The structure of an E. coli population in water is not stable, but depends on the hydrological conditions and on current use of the land on the watershed. In our study it was the ratio of A to B1 phylo-groups that changed. However, a set of B1 phylo-group isolates seems to be persistent in water, strengthening the hypothesis that they may correspond to specifically adapted strains.

  7. Monitoring Watershed Water Quality Impacts on Near-Shore Coral Reef Ecosystems in American Samoa using NASA Earth Observations

    Science.gov (United States)

    Teaby, A.; Price, J.; Minovitz, D.; Makely, L.; Torres-Perez, J. L.; Schmidt, C.; Guild, L. S.; Palacios, S. L.

    2014-12-01

    Land use changes can greatly increase erosion and sediment loads reaching watersheds and downstream coastal waters. In coastal environments with steep terrain and small drainage basins, sedimentation directly influences water quality in near-shore marine environments. Poor water quality indicators (i.e., dissolved nutrients and high particulates) affect coral calcification, photosynthesis, and coral cover. The abundance, recruitment, and biodiversity of American Samoa's coral reefs have been heavily affected by population growth, land cover change, pollution, and sediment influx. Monitoring, managing, and protecting these fragile ecosystems remains difficult due to limited resource availability, steep terrain, and local land ownership. Despite extensive field hours, traditional field and lab-based water quality research produces temporally and spatially limited datasets. Using a 'ridge to reef' effort, this project built a management tool to assess coral reef vulnerability using land use, hydrology, water quality, and coral reef cover in American Samoa to provide local agencies and partners with spatial representation of water quality parameters and site-specific implications for coral reef vulnerability. This project used land cover classified from Landsat 7 and 8 images, precipitation data from NOAA, and physical ocean factors from Terra MODIS. Changes in land cover from 2000 to 2014 were also estimated using Landsat imagery. Final products were distributed to partners to enhance water quality management, community outreach, and coral reef conservation.

  8. Planning of water resources management and pollution control for Heshui River watershed, China: A full credibility-constrained programming approach.

    Science.gov (United States)

    Zhang, Y M; Huang, G; Lu, H W; He, Li

    2015-08-15

    A key issue facing integrated water resources management and water pollution control is to address the vague parametric information. A full credibility-based chance-constrained programming (FCCP) method is thus developed by introducing the new concept of credibility into the modeling framework. FCCP can deal with fuzzy parameters appearing concurrently in the objective and both sides of the constraints of the model, but also provide a credibility level indicating how much confidence one can believe the optimal modeling solutions. The method is applied to Heshui River watershed in the south-central China for demonstration. Results from the case study showed that groundwater would make up for the water shortage in terms of the shrinking surface water and rising water demand, and the optimized total pumpage of groundwater from both alluvial and karst aquifers would exceed 90% of its maximum allowable levels when credibility level is higher than or equal to 0.9. It is also indicated that an increase in credibility level would induce a reduction in cost for surface water acquisition, a rise in cost from groundwater withdrawal, and negligible variation in cost for water pollution control. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. Relation between stream-water quality and geohydrology during base-flow conditions, Roberts creek watershed, Clayton County, Iowa

    Science.gov (United States)

    Kalkhoff, Stephen J.

    1995-01-01

    An investigation to determine the relation between stream water quality and geohydrology in the Roberts Creek watershed, Clayton County, Iowa, was conducted during selected base-flow periods in 1988-90. Discharge measurements were made and water samples collected for analyses of nutrients and selected herbicides in 19 subbasins along the main stem and tributaries of Roberts Creek. The areal extent of unconsolidated and bedrock units subcropping in each subbasin was quantified. The hydrologic data were correlated statistically with the geologic data to determine relations. Roberts Creek generally gained water and had larger nitrogen concentrations in subbasins in which loess and alluvial material were underlain primarily by low-permeability till and shale units. Roberts Creek generally lost water and had lower nitrate concentrations in subbasins with subcropping karstic units. Nitrogen concentrations decreased in streams underlain by the karstic units because the nitrogen removed by biological processes was not replaced by ground-water inflow. Seepage from Roberts Creek to ground water in areas of subcropping karstic carbonate rocks reduced the flow, which reduced the velocity, causing increased residence time of water in the stream. The additional residence time may allow additional time for biological processes to remove nitrogen from solution. There was no significant relation between dissolved orthophosphate or atrazine and the underlying geology.

  10. Identification and prioritization of subwatersheds for land and water management in Tekeze dam watershed, Northern Ethiopia

    Directory of Open Access Journals (Sweden)

    Kidane Welde

    2016-03-01

    Full Text Available Sedimentation and/or soil erosion are huge problems that have threatened many reservoirs in the Northern Ethiopian highlands, particularly in the Tekeze dam watershed. This study has been conducted to identify and prioritize the most sensitive subwatersheds with the help of a semi-distributed watershed model (SWAT 2009 for improved management of reservoir sedimentation mitigating strategies at the watershed level. SWAT 2009 was chosen for this study due to its ability to produce routed sediment yield and identify principal sediment source areas at the selected point of interest. Based on a digital elevation model (DEM the catchment was divided in to 47 subwatersheds using the dam axis as the main outlet. By overlaying land use, soil and slope of the study area, the subwatersheds were further divided in to 690 hydrological response units (HRUs. Model calibration (for the period of January 1996 to December 2002 and validation (for the period of January 2003 to December 2006 were carried out for stream flow rate and sediment yield data observed at Emba madre gage station. The results of model performance evaluation statistics for both stream flow and sediment yield shows that the model has a high potential in estimation of stream flow and sediment yield. Tekeze dam watershed has mean annual stream flow of 137.74 m3/s and annual sediment yield of 15.17 t/ha/year. Out of the 47 subwatersheds, 13 subwatersheds (mostly located in the north eastern and north western part of the catchment were prioritized. The maximum sediment outflow of these 13 subwatersheds, ranges from 18.49 to 32.57 t/ha/year and are characterized dominantly by cultivated land, shrub land & bare land with average land slope ranging from 7.9 to15.2% and with the dominant soil type of Eutric cambisols. These results can help to formulate and implement effective, appropriate and sustainable watershed management which in turn can help in sustaining the reservoir storage capacity of

  11. Calibration of SWAT model for woody plant encroachment using paired experimental watershed data

    Science.gov (United States)

    Qiao, Lei; Zou, Chris B.; Will, Rodney E.; Stebler, Elaine

    2015-04-01

    Globally, rangeland has been undergoing a transition from herbaceous dominated grasslands into tree or shrub dominated woodlands with great uncertainty of associated changes in water budget. Previous modeling studies simulated the impact of woody plant encroachment on hydrological processes using models calibrated and constrained primarily by historic streamflow from intermediate sized watersheds. In this study, we calibrated the Soil and Water Assessment Tool (SWAT model), a widely used model for cropping and grazing systems, for a prolifically encroaching juniper species, eastern redcedar (Juniperus virginiana), in the south-central Great Plains using species-specific biophysical and hydrological parameters and in situ meteorological forcing from three pairs of experimental watersheds (grassland versus eastern redcedar woodland) for a period of 3-years covering a dry-to-wet cycle. The multiple paired watersheds eliminated the potentially confounding edaphic and topographic influences from changes in hydrological processes related to woody encroachment. The SWAT model was optimized with the Shuffled complexes with Principal component analysis (SP-UCI) algorithm developed from the Shuffled Complexes Evolution (SCE_UA). The mean Nash-Sutcliff coefficient (NSCE) values of the calibrated model for daily and monthly runoff from experimental watersheds reached 0.96 and 0.97 for grassland, respectively, and 0.90 and 0.84 for eastern redcedar woodland, respectively. We then validated the calibrated model with a nearby, larger watershed undergoing rapid eastern redcedar encroachment. The NSCE value for monthly streamflow over a period of 22 years was 0.79. We provide detailed biophysical and hydrological parameters for tallgrass prairie under moderate grazing and eastern redcedar, which can be used to calibrate any model for further validation and application by the hydrologic modeling community.

  12. Is Groundwater Recharge Always Serving Us Well? Water Supply and Crop Production in Conflict in the Yahara River Watershed, Wisconsin

    Science.gov (United States)

    Booth, E.; Zipper, S. C.; Loheide, S. P.; Kucharik, C. J.

    2013-12-01

    Ecosystem service mapping is a rapidly growing field within ecology and sustainability science. Groundwater recharge is commonly treated as an ecosystem service and it can be estimated using readily available climate and soil parameters. However, groundwater recharge is only the entry-point to a complex groundwater flow system that includes both deep aquifers that municipalities tap into for water supply and shallow aquifers with water tables that can reach the ground surface. From an ecosystem service mapping perspective, groundwater recharge is almost universally treated as a beneficial service by increasing groundwater supply for municipal pumping, baseflow maintenance, and groundwater-dependent ecosystems. However, groundwater recharge can also lead to detrimental impacts such as groundwater flooding that can lead to crop losses (oxygen stress in vegetation) and property damage. While other ecosystem services that are commonly mapped provide benefits in situ (e.g. carbon sequestration), groundwater recharge belongs to a category where effects can be manifested much farther away in both space and time and can be both beneficial and detrimental to several final ecosystem services. This is the case in the Yahara River watershed, an urbanizing agricultural watershed in south-central Wisconsin. We document how groundwater recharge is treated as beneficial towards increasing municipal water supply through increasing use of infiltration practices, which are now legally required by local ordinances. We also show how an increasing precipitation trend has led to the view of groundwater recharge as detrimental towards crop production in fields where groundwater flooding and oxygen stress is evident. However, even in the same field, groundwater recharge can benefit and enhance crop production during drought conditions by decreasing water stress. These complicated and conflicting views of groundwater recharge lead to the recommendation of treating groundwater recharge as

  13. Climate and topographic controls on pasture production in a semiarid Mediterranean watershed with scattered tree cover

    Science.gov (United States)

    Lozano-Parra, J.; Maneta, M. P.; Schnabel, S.

    2013-12-01

    Natural grasses in semiarid rangelands constitute an effective protection against soil erosion and degradation, are a source of natural food for livestock and play a critical role in the hydrologic cycle by contributing to the uptake and transpiration of water. However, natural pastures are threatened by land abandonment and the consequent encroachment of shrubs and trees as well as by changing climatic conditions. In spite of their ecological and economic importance, the spatio-temporal variations of pasture production at the decadal to century scales over whole watersheds are poorly known. We used a physics-based, spatially-distributed ecohydrologic model applied to a 99.5 ha semiarid watershed in western Spain to investigate the sensitivity of pasture production to climate variability. The ecohydrologic model was run using a 300 yr long synthetic daily climate dataset generated using a stochastic weather generator. The data set reproduced the range of climatic variations observed under current climate. Results indicated that variation of pasture production largely depended on factors that also determined the availability of soil moisture such as the temporal distribution of precipitation, topography, and tree canopy cover. The latter is negatively related with production, reflecting the importance of rainfall and light interception, as well as water consumption by trees. Valley bottoms and flat areas in the lower parts of the catchment are characterized by higher pasture production. A quantitative assessment of the quality of the simulations showed that ecohydrologic models are a valuable tool to investigate long term (century scale) water and energy fluxes, as well as vegetation dynamics, in semiarid rangelands.

  14. A GIS and statistical approach to identify variables that control water quality in hydrothermally altered and mineralized watersheds, Silverton, Colorado, USA

    Science.gov (United States)

    Yager, Douglas B.; Johnson, Raymond H.; Rockwell, Barnaby W.; Caine, Jonathan S.; Smith, Kathleen S.

    2013-01-01

    Hydrothermally altered bedrock in the Silverton mining area, southwest Colorado, USA, contains sulfide minerals that weather to produce acidic and metal-rich leachate that is toxic to aquatic life. This study utilized a geographic information system (GIS) and statistical approach to identify watershed-scale geologic variables in the Silverton area that influence water quality. GIS analysis of mineral maps produced using remote sensing datasets including Landsat Thematic Mapper, advanced spaceborne thermal emission and reflection radiometer, and a hybrid airborne visible infrared imaging spectrometer and field-based product enabled areas of alteration to be quantified. Correlations between water quality signatures determined at watershed outlets, and alteration types intersecting both total watershed areas and GIS-buffered areas along streams were tested using linear regression analysis. Despite remote sensing datasets having varying watershed area coverage due to vegetation cover and differing mineral mapping capabilities, each dataset was useful for delineating acid-generating bedrock. Areas of quartz–sericite–pyrite mapped by AVIRIS have the highest correlations with acidic surface water and elevated iron and aluminum concentrations. Alkalinity was only correlated with area of acid neutralizing, propylitically altered bedrock containing calcite and chlorite mapped by AVIRIS. Total watershed area of acid-generating bedrock is more significantly correlated with acidic and metal-rich surface water when compared with acid-generating bedrock intersected by GIS-buffered areas along streams. This methodology could be useful in assessing the possible effects that alteration type area has in either generating or neutralizing acidity in unmined watersheds and in areas where new mining is planned.

  15. Alterations in land uses based on amendments to the Brazilian Forest Law and their influences on water quality of a watershed

    Directory of Open Access Journals (Sweden)

    JL. Rodrigues-Filho

    Full Text Available The amendments to the Forest Law proposed by the Brazilian government that allow partial substitution of forested areas by agricultural activities raised deep concern about the integrity of aquatic ecosystems. To assess the impacts of this alteration in land uses on the watershed, diffuse loads of total nitrogen (Nt and total phosphorus (Pt were estimated in Lobo Stream watershed, southeastern Brazil, based on export coefficients of the Model of Correlation between Land Use and Water Quality (MQUAL. Three scenarios were generated: scenario 1 (present scenario, with 30-meter-wide permanent preservation areas along the shore of water bodies and 50-meter-radius in springs; scenario 2, conservative, with 100-meter-wide permanent preservation areas along water bodies; and scenario 3, with the substitution of 20% of natural forest by agricultural activities. Results indicate that a suppression of 20% of forest cover would cause an increase in nutrient loads as well as in the trophic state of aquatic ecosystems of the watershed. This could result in losses of ecosystem services and compromise the quality of water and its supply for the basin. This study underlines the importance of forest cover for the maintenance of water quality in Lobo Stream watershed.

  16. Global multi-scale segmentation of continental and coastal waters from the watersheds to the continental margins

    KAUST Repository

    Laruelle, G. G.

    2013-05-29

    Past characterizations of the land-ocean continuum were constructed either from a continental perspective through an analysis of watershed river basin properties (COSCATs: COastal Segmentation and related CATchments) or from an oceanic perspective, through a regionalization of the proximal and distal continental margins (LMEs: large marine ecosystems). Here, we present a global-scale coastal segmentation, composed of three consistent levels, that includes the whole aquatic continuum with its riverine, estuarine and shelf sea components. Our work delineates comprehensive ensembles by harmonizing previous segmentations and typologies in order to retain the most important physical characteristics of both the land and shelf areas. The proposed multi-scale segmentation results in a distribution of global exorheic watersheds, estuaries and continental shelf seas among 45 major zones (MARCATS: MARgins and CATchments Segmentation) and 149 sub-units (COSCATs). Geographic and hydrologic parameters such as the surface area, volume and freshwater residence time are calculated for each coastal unit as well as different hypsometric profiles. Our analysis provides detailed insights into the distributions of coastal and continental shelf areas and how they connect with incoming riverine fluxes. The segmentation is also used to re-evaluate the global estuarine CO2 flux at the air-water interface combining global and regional average emission rates derived from local studies. © 2013 Author(s).

  17. Assessing Changes in Impervious Area Using Land Use Maps of Different Resolution in the Croton NY City Water Supply Watershed

    Science.gov (United States)

    Somerlot, C.; Duncan, J.; Endreny, T.

    2001-05-01

    With the advance of remote sensing, options arise for the hydrologic modeler to access both public domain and privately contracted watershed land cover maps. Land use classification processes using aerial photographs are highly variable depending on tools and training, but distinction between impervious and pervious land cover is relatively simple. Hydrologic models will estimate different runoff timing, volume, and water quality depending on the percent imperviousness of the watershed. This research will examine how percent imperviousness varies with changes in both radiometric and spatial land cover map resolution. WinHSPF was run with four distinct land cover maps derived from remote imagery: MRLC (30 m), LULC (1 km), contracted aerial photos (1 m), and processed digital (1 M) ortho quarter quads. Comparisons were made between map percent impervious cover and runoff timing and volume. A modified export coefficient model that tracks pollutant discharge through down gradient filters examined how estimated nutrient loading changed with differences in these land cover map products. Methods are suggested for updating estimates of percent impervious cover in coarser resolution maps using field data or other means.

  18. Global multi-scale segmentation of continental and coastal waters from the watersheds to the continental margins

    KAUST Repository

    Laruelle, G. G.

    2012-10-04

    Past characterizations of the land–ocean continuum were constructed either from a continental perspective through an analysis of watershed river basin properties (COSCATs: COastal Segmentation and related CATchments) or from an oceanic perspective, through a regionalization of the proximal and distal continental margins (LMEs: large marine ecosystems). Here, we present a global-scale coastal segmentation, composed of three consistent levels, that includes the whole aquatic continuum with its riverine, estuarine and shelf sea components. Our work delineates comprehensive ensembles by harmonizing previous segmentations and typologies in order to retain the most important physical characteristics of both the land and shelf areas. The proposed multi-scale segmentation results in a distribution of global exorheic watersheds, estuaries and continental shelf seas among 45 major zones (MARCATS: MARgins and CATchments Segmentation) and 149 sub-units (COSCATs). Geographic and hydrologic parameters such as the surface area, volume and freshwater residence time are calculated for each coastal unit as well as different hypsometric pro- files. Our analysis provides detailed insights into the distributions of coastal and continental shelf areas and how they connect with incoming riverine fluxes. The segmentation is also used to re-evaluate the global estuarine CO2 flux at the air–water interface combining global and regional average emission rates derived from local studies.

  19. Fundamentals of watershed hydrology

    Science.gov (United States)

    Pamela J. Edwards; Karl W.J. Williard; Jon E. Schoonover

    2015-01-01

    This is a primer about hydrology, the science of water. Watersheds are the basic land unit for water resource management and their delineation, importance, and variation are explained and illustrated. The hydrologic cycle and its components (precipitation, evaporation, transpiration, soil water, groundwater, and streamflow) which collectively provide a foundation for...

  20. Watershed prioritization in the upper Han River basin for soil and water conservation in the South-to-North Water Transfer Project (middle route) of China.

    Science.gov (United States)

    Wu, Haibing

    2017-11-08

    Watershed prioritization with the objective of identifying critical areas to undertake soil and water conservation measures was conducted in the upper Han River basin, the water source area of approximately 95,000 km2 for the middle route of China's South-to-North Water Transfer Project. Based on the estimated soil erosion intensity in uplands and clustering analysis of measured nutrient concentrations in rivers, the basin was grouped into very-high-, high-, moderate-, and low-priority regions for water and soil conservation, respectively. The results indicated that soil erosion was primarily controlled by topography, and nutrients in rivers were associated with land use and land cover in uplands. Also, there was large spatial disparity between soil erosion intensity in the uplands and nutrient concentrations in the rivers across the basin. Analysis was then performed to prioritize the basin by the integration of the soil erosion intensity and water quality on a GIS platform in order to identify critical areas for water and soil conservation in the basin. The identified high-priority regions which occupy 5.74% of the drainage areas need immediate attention for soil and water conservation treatments, of which 5.28% is critical for soil erosion prevention and 0.46% for water conservation. Understandings of the basin environment and pollutant loading with spatial explicit are critical to the soil and water resource conservation for the interbasin water transfer project.

  1. An integrative approach to characterize hydrological processes and water quality in a semi-arid watershed in Northeastern Brazil

    Science.gov (United States)

    Franklin, M. R.; Fernandes, N.; Veiga, L. H. S.; Melo, L. R.; Santos, A. C. S.; Araujo, V. P.

    2014-12-01

    Arid and semi-arid regions face serious challenges in the management of scarce water resources. This situation tends to become worse with the increasing population growth rates and consequently increasing water demand. Groundwater is the most important water resource in these areas and, therefore, the sustainability of its use depends on the effectiveness in which it is managed, both in terms of quantity and quality. The Caetité Experimental Basin (CEB), located in a semi-arid region of Northeastern Brazil, faces not only the challenges associated with water scarcity, but also changes in landscape and potential contamination processes due to mining activity. The only active uranium production center in Brazil (URA) is located in this watershed and the sustainability of mining and milling operations as well as the survival of the local community are highly dependent on the availability of groundwater resources. Hydrogeological studies in this area are scarce, and the potential contamination and overexploitation of groundwater can not be ruled out. Therefore, a national project was launched in order to improve the understanding and quantification of the interaction between the hydrogeological system and human health. The methodological approach involved hydrological and geochemical monitoring and characterization of the CEB, use of isotopic techniques, groundwater modeling, water quality diagnosis and human health risk assessment due to water ingestion. The results suggested that the groundwater in the CEB are not totally connected, with evidence of a mixture of recent and old waters. The Na-Ca-HCO3-Cl is the dominant water type (50%) followed by Ca-Na-HCO3-Cl water type (17%). The relevant non-radioactive contaminants are Mn, F, NO3 and Ba, mostly from natural origin, with the exception of NO3 that could be associated with the livestock activities. The estimated effective doses due to groundwater ingestion containing radionuclides are below the recommended

  2. Watershed : The Role of Fresh Water in the Israeli-Palestinian Conflict

    International Development Research Centre (IDRC) Digital Library (Canada)

    Watershed décrit la crise de l'eau à laquelle font face aujourd'hui Israël et les Territoires occupés de la Palestine – crise qui aura beaucoup d'effet sur la conception et la réussite des propositions de paix en cours. Les auteurs analysent la géopolitique de l'eau dans la région, l'importance économique, les problèmes ...

  3. Rehabilitation of degraded rangelands: lessons learned

    Science.gov (United States)

    The introduction and subsequent invasion of cheatgrass (Bromus tectorum) has had astronomical effects to Great Basin rangelands. Cheatgrass has truncated secondary succession by outcompeting native plant species for limited resources, thus building persistent seed banks that take advantage of condi...

  4. Rangeland Ecology Monitoring Data : 1967-2013

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The dataset describes rangeland monitoring results from the Hanksville, UT (USA) area. Monitoring results consist of canopy cover of plant species and functional...

  5. Study of the quality and quantity of waters of a tributary watershed of Paraíba do Sul river- São Paulo, after environmental preservation actions

    Directory of Open Access Journals (Sweden)

    Alexandra Andrade

    2012-12-01

    Full Text Available Monitoring programs of water quality and quantity are necessary to provide subsidies to assess the conditions of the watersheds and for decision making regarding to the management of water resources. This study analyzed the quality and quantity of waters of the Macacos stream watershed, a tributary of the Paraíba do Sul river, in São Paulo State, by monitoring the parameters: temperature, pH, conductivity and dissolved oxygen at five sites in the watershed. The measurements of flow and height of water depth during dry and wet seasons of 2010 and 2011 allowed the construction of the "rating curve" in four points of water quality monitoring and to reconstruct the series of water flow in these seasons. The analysis results showed that there is indication of changes in water quality parameters due to the conservation practices adopted. The water temperature parameter was the most influenced by the seasonal variation in runoff. Several physical factors may have influenced the correlation of the other parameters with runoff, especially the different environmental recovery actions implemented in the study to achieve the sustainability of the water resources.

  6. Carrying capacity in arid rangelands during droughts: the role of temporal and spatial thresholds.

    Science.gov (United States)

    Accatino, F; Ward, D; Wiegand, K; De Michele, C

    2017-02-01

    Assessing the carrying capacity is of primary importance in arid rangelands. This becomes even more important during droughts, when rangelands exhibit non-equilibrium dynamics, and the dynamics of livestock conditions and forage resource are decoupled. Carrying capacity is usually conceived as an equilibrium concept, that is, the consumer density that can co-exist in long-term equilibrium with the resource. As one of the first, here we address the concept of carrying capacity in systems, where there is no feedback between consumer and resource in a limited period of time. To this end, we developed an individual-based model describing the basic characteristics of a rangeland during a drought. The model represents a rangeland composed by a single water point and forage distributed all around, with livestock units moving from water to forage and vice versa, for eating and drinking. For each livestock unit we implemented an energy balance and we accounted for the gut-filling effect (i.e. only a limited amount of forage can be ingested per unit time). Our results showed that there is a temporal threshold above which livestock begin to experience energy deficit and burn fat reserves. We demonstrated that such a temporal threshold increases with the number of animals and decreases with the rangeland conditions (amount of forage). The temporal threshold corresponded to the time livestock take to consume all the forage within a certain distance from water, so that the livestock can return to water for drinking without spending more energy than they gain within a day. In this study, we highlight the importance of a time threshold in the assessment of carrying capacity in non-equilibrium conditions. Considering this time threshold could explain contrasting observations about the influence of livestock number on livestock conditions. In case of private rangelands, the herd size should be chosen so that the spatial threshold equals (or exceeds) the length of the drought.

  7. Monitoring and assessment of surface water quality in Taquari-Antas Watershed, South Brazil-region with intensive pig farming.

    Science.gov (United States)

    Schneider, Vania Elisabete; Marques, Roger Vasques; Bortolin, Taison Anderson; Cemin, Gisele; Santos, Geise Macedo Dos

    2016-11-01

    Pig farming is one of the human activities carried out to meet the increasing food demand by the increasing population. South Brazil is the region with most intensive pig farming in the country, exerting pressure on the water and soil environments by the relevant pollutant emissions. Therefore, the main objective of this work was to assess pig farming pollution by monitoring superficial water qualities of the Taquari-Antas Watershed in South Brazil. The study area is about 8062 km(2) (south latitude 292,614, 282,624 and west longitude 520,802, 504,554). In 2014, there were 861 pig farmers and 739,858 animals were slaughtered. Samples were collected bimonthly from 13 spots during 2 years of monitoring. The main analysis included the determination of the water quality index (WQI)-a nine physicochemical and microbiological parameter index-and the trophic state index (TSI), which gives a trophic degree based on phosphorous and chlorophyll-α concentration to assess the impacts of the pig farming on superficial water of the region. The results suggest that the regions with high concentration of finishing stage farms present a higher risk to water quality. A distance of 4 km between different spots was enough to detect a significant decrease in the WQI. The WQI was found ranging from "regular" to "good" (62.77 and 78.95). The TSI were found to be mesotrophic at every spot during the entire period of the study.

  8. A Watershed Cooperative Addresses Short and Long-Term Perspectives for the Management of Harmful Algae at a Southwestern Ohio Drinking Water Reservoir

    Science.gov (United States)

    The multi-agency East Fork Watershed Cooperative (EFWCoop) has focused discussion and consequent leveraged monitoring efforts to understand how to ensure water safety in the short term. The EFWCoop is also collecting the dense data sets required to consider potential options for...

  9. A component-based, integrated spatially distributed hydrologic/water quality model: AgroEcoSystem-Watershed (AgES-W) overview and application

    Science.gov (United States)

    AgroEcoSystem-Watershed (AgES-W) is a modular, Java-based spatially distributed model which implements hydrologic/water quality simulation components. The AgES-W model was previously evaluated for streamflow and recently has been enhanced with the addition of nitrogen (N) and sediment modeling compo...

  10. Watershed Management Optimization Support Tool (WMOST) Workshop.

    Science.gov (United States)

    EPA's Watershed Management Optimization Support Tool (WMOST) version 2 is a decision support tool designed to facilitate integrated water management by communities at the small watershed scale. WMOST allows users to look across management options in stormwater (including green i...

  11. Techniques for detecting effects of urban and rural land-use practices on stream-water chemistry in selected watersheds in Texas, Minnesota,and Illinois

    Science.gov (United States)

    Walker, J.F.

    1993-01-01

    Although considerable effort has been expended during the past two decades to control nonpoint-source contamination of streams and lakes in urban and rural watersheds, little has been published on the effectiveness of various management practices at the watershed scale. This report presents a discussion of several parametric and nonparametric statistical techniques for detecting changes in water-chemistry data. The need for reducing the influence of natural variability was recognized and accomplished through the use of regression equations. Traditional analyses have focused on fixed-frequency instantaneous concentration data; this report describes the use of storm load data as an alternative.

  12. The Rangeland Hydrology and Erosion Model: A dynamic approach for predicting soil loss on rangelands

    Science.gov (United States)

    In this study we present the improved Rangeland Hydrology and Erosion Model (RHEM V2.3), a process-based erosion prediction tool specific for rangeland application. The article provides the mathematical formulation of the model and parameter estimation equations. Model performance is assessed agains...

  13. USDA internet tool to estimate runoff and soil loss on rangelands: rangelands hydrology and erosion model

    Science.gov (United States)

    Rangelands are the most dominant land cover type in the United States (770 million acres) with approximately 53% of the nation’s rangelands owned and managed by the private sector, while approximately 43% are managed by the federal government. Information on the type, extent, and spatial location of...

  14. Stream restoration and sanitary infrastructure alter sources and fluxes of water, carbon, and nutrients in urban watersheds

    Science.gov (United States)

    Pennino, M. J.; Kaushal, S. S.; Mayer, P. M.; Utz, R. M.; Cooper, C. A.

    2015-12-01

    An improved understanding of sources and timing of water and nutrient fluxes associated with urban stream restoration is critical for guiding effective watershed management. We investigated how sources, fluxes, and flowpaths of water, carbon (C), nitrogen (N), and phosphorus (P) shift in response to differences in stream restoration and sanitary infrastructure. We compared a restored stream with 3 unrestored streams draining urban development and stormwater management over a 3 year period. We found that there was significantly decreased peak discharge in response to precipitation events following stream restoration. Similarly, we found that the restored stream showed significantly lower monthly peak runoff (9.4 ± 1.0 mm d-1) compared with two urban unrestored streams (ranging from 44.9 ± 4.5 to 55.4 ± 5.8 mm d-1) draining higher impervious surface cover. Peak runoff in the restored stream was more similar to a less developed stream draining extensive stormwater management (13.2 ± 1.9 mm d-1). Interestingly, the restored stream exported most carbon, nitrogen, and phosphorus loads at relatively lower streamflow than the 2 more urban streams, which exported most of their loads at higher and less frequent streamflow. Annual exports of total carbon (6.6 ± 0.5 kg ha-1 yr-1), total nitrogen (4.5 ± 0.3 kg ha-1 yr-1), and total phosphorus (161 ± 15 g ha-1 yr-1) were significantly lower in the restored stream compared to both urban unrestored streams (p storm drains. Goundwater sources, fluxes, and flowpath should also be targeted in efforts to improve stream restoration strategies and prioritize hydrologic "hot spots" along watersheds where stream restoration is most likely to succeed.

  15. A watershed approach to upgrade rainfed agriculture in water scarce regions through Water System Innovations: an integrated research initiative on water for food and rural livelihoods in balance with ecosystem functions

    Science.gov (United States)

    Rockström, J.; Folke, C.; Gordon, L.; Hatibu, N.; Jewitt, G.; Penning de Vries, F.; Rwehumbiza, F.; Sally, H.; Savenije, H.; Schulze, R.

    The challenge of producing food for a rapidly increasing population in semi-arid agro-ecosystems in Southern Africa is daunting. More food necessarily means more consumptive use of so-called green water flow (vapour flow sustaining crop growth). Every increase in food production upstream in a watershed will impact on water user and using systems downstream. Intensifying agriculture has in the past often been carried out with negative side effects in terms of land and water degradation. Water legislation is increasingly incorporating the requirement to safeguard a water reserve to sustain instream ecology. To address the challenges of increasing food production, improving rural livelihoods, while safeguarding critical ecological functions, a research programme has recently been launched on “Smallholder System Innovations in Integrated Watershed Management” (SSI). The programme takes an integrated approach to agricultural water management, analysing the interactions between the adoption and participatory adaptation of water system innovations (such as water harvesting, drip irrigation, conservation farming, etc.), increased water use in agriculture and water flows to sustain ecological functions that deliver critical ecosystem services to humans. The research is carried out in the Pangani Basin in Tanzania and the Thukela Basin in South Africa. A nested scale approach is adopted, which will enable the analysis of scale interactions between water management at the farm level, and cascading hydrological impacts at watershed and basin scale. This paper describes the integrated research approach of the SSI programme, and indicates areas of potential to upgrade rainfed agriculture in water scarcity-prone agro-ecosystems while securing water for downstream use.

  16. Effects of highway construction on stream water quality and macroinvertebrate condition in a mid-atlantic highlands watershed, USA.

    Science.gov (United States)

    Chen, Yushun; Viadero, Roger C; Wei, Xinchao; Fortney, Ronald; Hedrick, Lara B; Welsh, Stuart A; Anderson, James T; Lin, Lian-Shin

    2009-01-01

    Refining best management practices (BMPs) for future highway construction depends on a comprehensive understanding of environmental impacts from current construction methods. Based on a before-after-control impact (BACI) experimental design, long-term stream monitoring (1997-2006) was conducted at upstream (as control, n = 3) and downstream (as impact, n = 6) sites in the Lost River watershed of the Mid-Atlantic Highlands region, West Virginia. Monitoring data were analyzed to assess impacts of during and after highway construction on 15 water quality parameters and macroinvertebrate condition using the West Virginia stream condition index (WVSCI). Principal components analysis (PCA) identified regional primary water quality variances, and paired t tests and time series analysis detected seven highway construction-impacted water quality parameters which were mainly associated with the second principal component. In particular, impacts on turbidity, total suspended solids, and total iron during construction, impacts on chloride and sulfate during and after construction, and impacts on acidity and nitrate after construction were observed at the downstream sites. The construction had statistically significant impacts on macroinvertebrate index scores (i.e., WVSCI) after construction, but did not change the overall good biological condition. Implementing BMPs that address those construction-impacted water quality parameters can be an effective mitigation strategy for future highway construction in this highlands region.

  17. Site Suitability Analysis of Water Harvesting Structures Using Remote Sensing and GIS - A Case Study of Pisangan Watershed, Ajmer District, Rajasthan

    Science.gov (United States)

    Prasad, H. C.; Bhalla, P.; Palria, S.

    2014-12-01

    Rajasthan is a region with very limited water resources. Water is the most crucial for maintaining an environment and ecosystem conducive to sustaining all forms of life. The principle of watershed management is the proper management of all the precipitation by the way of collection, storage and efficient utilization of runoff water and to recharge the ground water. The present study aim's to identify suitable zones for water harvesting structures in Pisangan watershed of Ajmer district, Rajasthan by using Geographic Information System (GIS) and Multi Criteria Evaluation (MSE). Multi criteria evaluation is carried out in Geographic Information system to help the decision makers in determining suitable zones for water harvesting structures based on the physical characteristics of the watershed. Different layers which were taken into account for multi criteria evaluation are; Soil texture, slope, rainfall data (2000-2012), land use/cover, geomorphology, lithology, lineaments, drainage network. The soil conservation service model was used to estimate the runoff depth of the study area Analytical Hierarchy Processes (AHP) is used to find suitable water harvesting structures on the basis of rainfall. Produced suitability map will help in the selection of harvesting structures such as percolation tanks, storage tank, check dams and stop dams.

  18. Calibration and validation of SWAT model for estimating water balance and nitrogen losses in a small agricultural watershed in central Poland

    Directory of Open Access Journals (Sweden)

    Smarzyńska Karolina

    2016-06-01

    Full Text Available Soil and Water Assessment Tool (SWAT ver. 2005 was applied to study water balance and nitrogen load pathways in a small agricultural watershed in the lowlands of central Poland. The natural flow regime of the Zgłowiączka River was strongly modified by human activity (deforestation and installation of a subsurface drainage system to facilitate stable crop production. SWAT was calibrated for daily and monthly discharge and monthly nitrate nitrogen load. Model efficiency was tested using manual techniques (subjective and evaluation statistics (objective. Values of Nash–Sutcliffe efficiency coefficient (NSE, coefficient of determination (R2 and percentage of bias for daily/monthly discharge simulations and monthly load indicated good or very good fit of simulated discharge and nitrate nitrogen load to the observed data set. Model precision and accuracy of fit was proved in validation. The calibrated and validated SWAT was used to assess water balance and nitrogen fluxes in the watershed. According to the results, the share of tile drainage in water yield is equal to 78%. The model analysis indicated the most significant pathway of NO3-N to surface waters in the study area, namely the tile drainage combined with lateral flow. Its share in total NO3-N load amounted to 89%. Identification of nitrogen fluxes in the watershed is crucial for decision makers in order to manage water resources and to implement the most effective measures to limit diffuse pollution from arable land to surface waters.

  19. Hydrologic model parameterization using dynamic Landsat-based foliar cover estimates for runoff simulation on a semiarid grassland watershed

    Science.gov (United States)

    Kautz, Mark A.

    Changes in watershed vegetative cover from natural and anthropogenic causes including, climatic fluctuations, wildfires and land management practices, can result in increased surface water runoff and erosion. Hydrologic models play an important role in the decision support process for managing these landscape alterations. However, model parameterization requires quantified measures of watershed biophysical condition to generate accurate results. These inputs are often obtained from nationally available land cover data sets that are static in terms of vegetation condition and phenology. Obtaining vegetative data for model input of sufficient spatiotemporal resolution for long-term, watershed-scale change analysis has been a challenge. The purpose of this research was to assess the implications of parameterizing the event-based, Rangeland Hydrology and Erosion Model (RHEM) with dynamic, remotely sensed foliar cover data. The study was conducted on a small, instrumented, grassland watershed within the Walnut Gulch Experimental Watershed surrounding Tombstone, Arizona. A time series of foliar cover rasters was produced by calibrating Landsat-based Soil Adjusted Total Vegetation Index (SATVI) scenes with field measurements. Estimates of basal and litter cover were calculated using allometric relationships derived from ground-based transect data. The model was parameterized using these remotely sensed inputs for all recorded runoff events from 1996-2014. Model performance was improved using the remotely sensed foliar cover compared to using an a priori value based on static national land cover classes. Significant (plitter cover. The integration of Landsat-based vegetative data into RHEM shows potential for modelling on a broadened spatiotemporal scale, allowing for improved landscape characterization and the ability to track watershed response to long-term vegetation changes.

  20. Spatial and temporal characterization of some water quality physical parameters and their relationships with land-use in Água Fria watershed (Palmas – TO, Brazil

    Directory of Open Access Journals (Sweden)

    Harry Edmar Schulz

    2007-06-01

    Full Text Available Due to a high population growth that has been occurring in Palmas and due to land use changes that are caused by this population growth and development, the goal of this paper was to study the behavior of four physical parameters of water quality of the Água Fria watershed. The parameters were turbidity, total suspended solids, settleable solids and total dissolved solids. Eight gauging stations were established and the water samples were monthly collected from February/1998 to February/1999. The water bodies of the watershed were generally in good condition concerning these four parameters. However, there were some cases of seasonal irregularity of some parameters, as well as no correlation among some of studied parameters. This might be an indicator of some impacts like accelerated erosion due to a misuse of the lands and misuse of local water resources.

  1. Water- and air-quality and surficial bed-sediment monitoring of the Sweetwater Reservoir watershed, San Diego County, California, 2003-09

    Science.gov (United States)

    Mendez, Gregory O.; Majewski, Michael S.; Foreman, William T.; Morita, Andrew Y.

    2015-01-01

    In 1998, the U.S. Geological Survey, in cooperation with the Sweetwater Authority, began a study to assess the overall health of the Sweetwater watershed in San Diego County, California. This study was designed to provide a data set that could be used to evaluate potential effects from the construction and operation of State Route 125 within the broader context of the water quality and air quality in the watershed. The study included regular sampling of water, air, and surficial bed sediment at Sweetwater Reservoir (SWR) for chemical constituents, including volatile organic compounds (VOCs), base-neutral and acid- extractable organic compounds (BNAs) that include polycyclic aromatic hydrocarbons (PAHs), pesticides, and metals. Additionally, water samples were collected for anthropogenic organic indicator compounds in and around SWR. Background water samples were collected at Loveland Reservoir for VOCs, BNAs, pesticides, and metals. Surficial bed-sediment samples were collected for PAHs, organochlorine pesticides, and metals at Sweetwater and Loveland Reservoirs.

  2. A comparison of the geochemical signatures of water-rock interaction and erosion rates between developed and undeveloped watersheds, St. John, US Virgin Islands

    Science.gov (United States)

    Gudino, N.; Kretzschmar, T.; Gray, S. C.

    2012-12-01

    Human activities such as deforestation, agriculture, and the building of dirt roads may increase soil erosion and the delivery of land-based sediment into coastal waters from steep sub-tropical islands. These changes may also affect water-rock interaction, which alters the geochemistry of storm waters and the clay mineralogy of eroded sediments. In the US Virgin Islands, land-based sedimentation is thought to be a major cause of the decline of near-shore coral reefs. The objective of this study was to 1) evaluate whether chemical erosion (water-rock interaction) during storms affected the major-element chemistry of storm-water and the clay mineralogy of eroded sediments; and 2) determine if enhanced erosion associated with human activities may impact these parameters. Our approach was to compare storm-water and sediment geochemistry and modeled erosion rates between developed (Coral Bay) and undeveloped (Lameshur) watersheds on St. John, USVI. Terrestrial and marine sediment samples and runoff samples from three storm events, including Hurricane Otto (Oct. 7-9th), were collected during the 2010 hurricane season in Coral Bay and Lameshur watersheds and bays. Major elements in storm waters were measured using ICP-AES. The mineral saturation index was calculated using "The Geochemist's Workbench" (GWB), supported by X-Ray Diffraction analysis on clay minerals. The Revised and Modified Universal Soil Loss Equations were used to estimate both annual mean (2010, RUSLE) and storm-event (Hurricane Otto, MUSLE) based erosion rates. In addition, rates of marine terrigenous sediment accumulation were estimated by Loss On Ignition (LOI) analysis of marine sediment collected using submarine sediment trap arrays. Spatial variations in calcium, magnesium, sodium and potassium concentrations in storm water samples were measured and only calcium was statistical different (p<0.05) between the developed and undeveloped study sites during Hurricane Otto. Event specific differences in

  3. Using rangeland health assessment to inform successional management

    Science.gov (United States)

    Rangeland health assessment provides qualitative information on ecosystem attributes. Successional management is a conceptual framework that allows managers to link information gathered in rangeland health assessment to ecological processes that need to be repaired to allow vegetation to change in ...

  4. Collaborative adaptive rangeland management fosters management-science partnerships

    Science.gov (United States)

    Rangelands of the western Great Plains of North America are complex social-ecological systems where management objectives for livestock production, grassland bird conservation and vegetation structure and composition converge. The Collaborative Adaptive Rangeland Management (CARM) experiment is a 10...

  5. Quality of ground water around Vadnais Lake and in Lambert Creek watershed, and interaction of ground water with Vadnais Lake, Ramsey County, Minnesota

    Science.gov (United States)

    Ruhl, J.F.

    1994-01-01

    Vadnais Lake is located in northern Ramsey County, Minnesota. The lake is managed by the St. Paul Water Utility for storage of municipal water supplies that are provided to residents of St. Paul and surrounding communities. In recent years, algal blooms in Vadnais Lake have caused taste and odor problems in St. Paul's municipal water supply. This problem has potentially been exacerbated by phosphorus enrichment of the lake from surface-water transport and from nutrient recycling between the lake and bottom sediments. Phosphorus loading in Vadnais Lake has been linked to increased algal growth. Surface-water drainage from supply lakes and, during wet years, from wetlands in Lambert Creek watershed, which extends over about 20 square miles east of the lake, is known to be a significant source of phosphorus. The role of ground water in the phosphorus budget of the lake was unknown. The results of this study indicate that ground-water transport of phosphorus into Vadnais Lake is a small part of the phosphorus budget of the lake.

  6. Spatial and temporal analysis of land cover change, sedimentation and water quality in the Lake Issaqueena watershed, South Carolina

    Science.gov (United States)

    Pilgrim, Cassie Mechele

    Soil erosion and increased sediment yields within a watershed lead to impaired water quality, decreased availability of wildlife habitat and reduced recreational opportunities. While some sedimentation occurs naturally within a water system, most erosion processes are the result of anthropogenic activities across a landscape, namely changes in land use and land cover (LULC). This study was conducted to determine temporal and spatial sedimentation trends in the Lake Issaquena watershed using sonar logging equipment, geographic information systems (GIS) and limited hydrologic data from the Soil Conservation Service (1941 and 1949). Sediment deposition was analyzed in relation to several key factors that influence erosion and sediment yields; these being dominant land cover, topography and slopes, soils and geology, rainfall and climatological aspects. Significant sedimentation has occurred in the Sixmile Creek delta, located at the northern end of Lake Issaqueena. Sedimentation rates inferred from an analysis of afore mentioned factors show considerable changes in erosion potential that correspond with substantial changes in riparian vegetation, extreme variations in rainfall events, conversion of land from agricultural to forestland and application of management practices. Water quality data, including sampling depth, water temperature, dissolved oxygen content, Fecal coliform levels, inorganic nitrogen concentrations and turbidity, were obtained from the South Carolina Department of Environmental Health and Safety (SCDHEC) for two stations and analyzed for trends as they related to land cover change. Data was available for the Sixmile Creek site for dates ranging from 1962 to 2005 and from 1999 to 2005 for the Lake Issaqueena site. From 1951 to 2009, the watershed experienced an increase of tree cover and bare ground (+17.4% evergreen, +62.3% deciduous, +9.8% bare ground) and a decrease of pasture/ grassland and cultivated (-42.6% pasture/ grassland, -57

  7. Long-term water repellency in organic olive orchards in the Cànyoles River watershed. The impact of land management

    Science.gov (United States)

    Cerdà, Artemi; González Pelayo, Óscar; García Orenes, Fuensanta; Jordán, Antonio; Pereira, Paulo; Novara, Agata; Neris, Jonay

    2015-04-01

    Soil water repellency is being researched in many enviroments of the world due to the fact that after two decades of intense investigations we found that soil water repellency is a soil property that can be found at any ecosystem (Atanassava and Doerr, 2011; Goebel et al., 2011; Mataix-Solera et al., 2013; Roper et al., 2013; Young et al., 2013; Badía-Villas et al., 2014; Jordán et al., 2014; Whelan et al., 2014). Soil water repellency inhibits or delays infiltration, encourage surface runoff but also the preferential flow in cracks and other macropores (Arye et al., 2011; Jordán et al., 2011; Madsen et al., 2011; Spohn and Rilling, 2012; García-Moreno et al., 2013; Hallin et al., 2013). Water repellency has been found in many soil types and it is present after forest fire, on forested land and also in agriculture soils (Granjed et al., 2013; Bodí et al., 2012; García Orenes et al., 2013; Jordán et al., 2012; Bodí et al., 2013; Dlapa et al., 2013; González-Peñaloza et al., 2012; López Garrido et al., 2012; León et al., 2013; Hewelke et al., 2014; Santos et al., 2014; Kröpfl et al., 2013). This paper show the measurements caried out by means of the water drop penetration time (WDPT) method in olive plantation in the Cànyoles watershed in Eastern Spain. Conservation practices applied such as no-tillage, manure addition, application of herbicides may contribute to increase soil organic matter and, hence, soil water repellency, and this is unknow under Mediterranean type ecosystems. The effect of long-term addition of plant residues and organic manure, no-tillage and no chemical fertilization (MNT), annual addition of plant residues and no-tillage (NT), application of conventional herbicides and no-tillage (H), and conventional tillage (CT) on soil water repellency in Mediterranean calcareous citrus-cropped soils (Eastern Spain) has been studied. Water repellency was observed in MNT soils, which may be attributed to the input of hydrophobic organic

  8. Rangelands: Where Anthromes Meet Their Limits

    Directory of Open Access Journals (Sweden)

    Nathan F. Sayre

    2017-05-01

    Full Text Available Defining rangelands as anthromes enabled Ellis and Ramankutty (2008 to conclude that more than three-quarters of Earth’s land is anthropogenic; without rangelands, this figure would have been less than half. They classified all lands grazed by domestic livestock as rangelands, provided that human population densities were low; similar areas without livestock were excluded and classified instead as ‘wildlands’. This paper examines the empirical basis and conceptual assumptions of defining and categorizing rangelands in this fashion. Empirically, we conclude that a large proportion of rangelands, although used to varying degrees by domesticated livestock, are not altered significantly by this use, especially in arid, highly variable environments and in settings with long evolutionary histories of herbivory by wild animals. Even where changes have occurred, the dynamics and components of many rangelands remain structurally and functionally equivalent to those that preceded domestic livestock grazing or would be found in its absence. In much of Africa and Asia, grazing is so longstanding as to be inextricable from ‘natural’ or reference conditions for those sites. Thus, the extent of anthropogenic biomes is significantly overstated. Conceptually, rangelands reveal the dependence of the anthromes thesis on outdated assumptions of ecological climax and equilibrium. Coming to terms with rangelands—how they can be classified, understood, and managed sustainably—thus offers important lessons for understanding anthromes and the Anthropocene as a whole. At the root of these lessons, we argue, is not the question of human impacts on ecosystems but property relations among humans.

  9. Water Quality Assessment of the Los Angeles River Watershed, California, USA in Wet and Dry Weather Periods

    Science.gov (United States)

    Rezaie Boroon, M. H.; Von L Coo, C.

    2015-12-01

    The purpose of this study is to identify sources of potential pollutants and characterize urban water quality along the Los Angeles River from its head to the mouth during dry and wet weather periods. Los Angeles (LA) River flows through heavily populated urbanized area in the Los Angeles downtown. The LA River is an effluent-dominated water body during the dry season. The three waste water treatment plants (WWTP) including the Tillman, Burbank, and Glendale discharge the majority of the volume flowing in the LA River during the dry and wet period. The concentration values (ppm) for anions in the dry season ranging 5.5-16,027 (Cl), 0-1.0 (F), 0-21(NO3), 0-1.6 (PO4), and 13.3-2,312 (SO4); whereas the values (ppm) for anions in the wet season ranging 3.4-5,860 (Cl), 0-0.66 (F), 0-17 (NO3), 0-0.67 (PO4), 7.9- 745 (SO4). Dry season concentrations values for trace metals were obtained with values (ppb) ranging 0.9-10 (Ni), 0.8-62 (Zn), 1-4 (As), 0-1 (Pb) and 0-3 (Se). As for wet season trace metals (ppb) ranging 0.001-0.008 (Ni), 0.000001-0.038 (Zn), 0.0016-0.016 (As), 0.00099-0.0058 (Pb), 0.000001-0.0093 (Se). Higher concentrations values during the dry period in the LA River watershed may be attributed to the three WWTPs discharge (75% of the volume of water flowing in the LA River). In water-limited areas such as the Los Angeles basin, urban runoff is a water resource that could enhance restricted water supplies and to enhance localized renewable groundwater resources, thus an assessment of this precious water resource is important for local city and regulatory organizations. In water-limited areas such as the LA basin, urban runoff is a water resource that could enhance restricted water supplies and groundwater resources, thus an assessment of this precious water resource is important for local regulatory organizations.

  10. Inferring land use and land cover impact on stream water quality using a Bayesian hierarchical modeling approach in the Xitiaoxi River Watershed, China.

    Science.gov (United States)

    Wan, Rongrong; Cai, Shanshan; Li, Hengpeng; Yang, Guishan; Li, Zhaofu; Nie, Xiaofei

    2014-01-15

    Lake eutrophication has become a very serious environmental problem in China. If water pollution is to be controlled and ultimately eliminated, it is essential to understand how human activities affect surface water quality. A recently developed technique using the Bayesian hierarchical linear regression model revealed the effects of land use and land cover (LULC) on stream water quality at a watershed scale. Six LULC categories combined with watershed characteristics, including size, slope, and permeability were the variables that were studied. The pollutants of concern were nutrient concentrations of total nitrogen (TN) and total phosphorus (TP), common pollutants found in eutrophication. The monthly monitoring data at 41 sites in the Xitiaoxi Watershed, China during 2009-2010 were used for model demonstration. The results showed that the relationships between LULC and stream water quality are so complicated that the effects are varied over large areas. The models suggested that urban and agricultural land are important sources of TN and TP concentrations, while rural residential land is one of the major sources of TN. Certain agricultural practices (excessive fertilizer application) result in greater concentrations of nutrients in paddy fields, artificial grasslands, and artificial woodlands. This study suggests that Bayesian hierarchical modeling is a powerful tool for examining the complicated relationships between land use and water quality on different scales, and for developing land use and water management policies. Copyright © 2013 Elsevier Ltd. All rights reserved.

  11. Influence of poultry litter land application on the concentrations of estrogens in water and sediment within a watershed.

    Science.gov (United States)

    Luo, Qi; Adams, Paige; Lu, Junhe; Cabrera, Miguel; Huang, Qingguo

    2013-07-01

    This research studied the occurrence of estrogens in the Upper Satilla watershed, Georgia, USA, which was impacted by poultry litter land application and discharge from a sewage treatment plant (STP) receiving poultry wastes. Over 14 months, four estrogens in stream water, sediment, suspended particles, and STP samples were quantified by LC/MS. Estrogens were consistently found in the STP influent with high concentrations while they were below the detection limits in the majority of stream water, suspended particles, and sediment. Estrone, 17β-estradiol, and estriol were found in 18% of stream water samples with concentrations up to 46.4, 67.2, and 125 ng L(-1), respectively. However, 17α-ethinylestradiol was only detected in STP samples. Estrogens were found in 14% of suspended particle samples with the median concentration being 27.5 ng g(-1) for estrone, 104.5 ng g(-1) for 17β-estradiol, and 93.9 ng g(-1) for estriol. The estrogen concentrations in sediment were litter disposal and rainfall events.

  12. Temporal trends in water-quality constituent concentrations and annual loads of chemical constituents in Michigan watersheds, 1998–2013

    Science.gov (United States)

    Hoard, Christopher J.; Fogarty, Lisa R.; Duris, Joseph W.

    2018-02-21

    In 1998, the Michigan Department of Environmental Quality and the U.S. Geological Survey began the Water Chemistry Monitoring Program for select streams in the State of Michigan. Objectives of this program were to provide assistance with (1) statewide water-quality assessments, (2) the National Pollutant Discharge Elimination System permitting process, and (3) water-resource management decisions. As part of this program, water-quality data collected from 1998 to 2013 were analyzed to identify potential trends for select constituents that were sampled. Sixteen water-quality constituents were analyzed at 32 stations throughout Michigan. Trend analysis on the various water-quality data was done using either the uncensored Seasonal Kendall test or through Tobit regression. In total, 79 trends were detected in the constituents analyzed for 32 river stations sampled for the study period—53 downward trends and 26 upward trends were detected. The most prevalent trend detected throughout the State was for ammonia, with 11 downward trends and 1 upward trend estimated.In addition to trends, constituent loads were estimated for 31 stations from 2002 to 2013 for stations that were sampled 12 times per year. Loads were computed using the Autobeale load computation program, which used the Beale ratio estimator approach to estimate an annual load. Constituent loads were the largest in large watershed streams with the highest annual flows such as the Saginaw and Grand Rivers. Likewise, constituent loads were the smallest in smaller tributaries that were sampled as part of this program such as the Boardman and Thunder Bay Rivers.

  13. The quantification of rangeland condition in a semi-arid grassland of ...

    African Journals Online (AJOL)

    The degradation gradient technique was used to quantify rangeland .condition in areas ranging from poor, trampled areas close to watering points to well managed areas in a semi-arid. sweet grassland of southern Africa. Ecological values were linked to species by means of their individual positions on the degradation ...

  14. Future of America's Forests and Rangelands: Update to the 2010 Resources Planning Act Assessment

    Science.gov (United States)

    Forest Service U.S. Department of Agriculture

    2016-01-01

    The Update to the 2010 Resources Planning Act (RPA) Assessment summarizes findings about the status, trends, and projected future of forests, rangelands, wildlife, biodiversity, water, outdoor recreation, and urban forests, as well as the effects of climate change upon these resources. Varying assumptions about population and economic growth, land use change, and...

  15. Effects of climate change on rangeland vegetation in the northern Rockies [Chapter 6

    Science.gov (United States)

    Matt C. Reeves; Mary E. Manning; Jeff P. DiBenedetto; Kyle A. Palmquist; William K. Lauenroth; John B. Bradford; Daniel R. Schlaepfer

    2017-01-01

    A longer growing season with climate change is expected to increase net primary productivity of many rangeland types, especially those dominated by grasses, although responses will depend on local climate and soil conditions. Elevated atmospheric carbon dioxide may increase water use efficiency and productivity of some species. In many cases, increasing wildfire...

  16. Factors controlling soil water and stream water aluminum concentrations after a clearcut in a forested watershed with calcium-poor soils

    Science.gov (United States)

    McHale, M.R.; Burns, Douglas A.; Lawrence, G.B.; Murdoch, Peter S.

    2007-01-01

    The 24 ha Dry Creek watershed in the Catskill Mountains of southeastern New York State USA was clearcut during the winter of 1996-1997. The interactions among acidity, nitrate (NO3- ), aluminum (Al), and calcium (Ca2+) in streamwater, soil water, and groundwater were evaluated to determine how they affected the speciation, solubility, and concentrations of Al after the harvest. Watershed soils were characterized by low base saturation, high exchangeable Al concentrations, and low exchangeable base cation concentrations prior to the harvest. Mean streamwater NO3- concentration was about 20 ??mol l-1 for the 3 years before the harvest, increased sharply after the harvest, and peaked at 1,309 ??mol l -1 about 5 months after the harvest. Nitrate and inorganic monomeric aluminum (Alim) export increased by 4-fold during the first year after the harvest. Alim mobilization is of concern because it is toxic to some fish species and can inhibit the uptake of Ca2+ by tree roots. Organic complexation appeared to control Al solubility in the O horizon while ion exchange and possibly equilibrium with imogolite appeared to control Al solubility in the B horizon. Alim and NO3- concentrations were strongly correlated in B-horizon soil water after the clearcut (r2 = 0.96), especially at NO3- concentrations greater than 100 ??mol l-1. Groundwater entering the stream from perennial springs contained high concentrations of base cations and low concentrations of NO3- which mixed with acidic, high Alim soil water and decreased the concentration of Alim in streamwater after the harvest. Five years after the harvest soil water NO 3- concentrations had dropped below preharvest levels as the demand for nitrogen by regenerating vegetation increased, but groundwater NO3- concentrations remained elevated because groundwater has a longer residence time. As a result streamwater NO3- concentrations had not fallen below preharvest levels, even during the growing season, 5 years after the harvest

  17. Social and Economic Indicators of the Sustainable Rangelands Roundtable

    Science.gov (United States)

    John E. Mitchell; Daniel W. McCallum; Lewis E. Swanson; John Tanaka; Mark Brunson; Aaron Harp; L. Allen Torell; H. Theodore Heintz

    2006-01-01

    Social and economic systems provide a context and rationale for rangeland management. Sustaining rangeland ecosystems requires attention to the social and economic conditions that accompany the functioning of those systems. We present and discuss economic and social indicators for rangeland sustainability that have possible relevance in the United States. A brief...

  18. Institutional arrangements for controlling nonpoint source water pollution: Wisconsin's Root River watershed

    National Research Council Canada - National Science Library

    Sawicki, D.S; Judd, L.B

    1982-01-01

    This report details a case study of a voluntary, decentralized institutional arrangement for managing nonpoint source water pollution control used in the Root River water shed in southeastern Wisconsin...

  19. EnviroAtlas - Watershed Index Online Water Mask for the Conterminous United States

    Data.gov (United States)

    U.S. Environmental Protection Agency — This data layer represents all surface water features in the United States. This grid was created by combining water features identified in two sources, the Cropland...

  20. Public participation in water resources management: Restructuring model of upstream Musi watershed

    Science.gov (United States)

    Andriani, Yuli; Zagloel, T. Yuri M.; Koestoer, R. H.; Suparmoko, M.

    2017-11-01

    Water is the source of life needed by living things. Human as one of living most in needs of water. Because the population growth follows the geometrical progression, while the natural resource increases calculates the arithmetic. Humans besides needing water also need land for shelter and for their livelihood needs, such as gardening or rice farmers. If the water absorption area is reduced, water availability will decrease. Therefore it is necessary to conduct an in-depth study of water resources management involving the community. The purpose of this study is to analyze community participation in water resources management, so that its availability can still meet the needs of living and sustainable. The method that used the level of community participation according to Arstein theory. The results obtained that community participation is at the level of partnership and power delegation. This level of participation is at the level of participation that determines the sustainability of water resources for present and future generations.

  1. Linking levels of societal and ecosystems metabolism of water in a Mediterranean watershed

    Science.gov (United States)

    Cabello, V.

    2014-12-01

    Water resources degradation is a complex environmental problem that involves multiple dimensions and scales of analysis. The Socio-Ecological Systems Water Metabolism has been proposed as a general holistic framework to deal with integrated analysis of water use sustainability (Madrid and Giampietro 2014). The innovation of the approach is that it sets the research focus beyond the classical supply-demand modeling to societal integrity and ecosystems integrity. To do so, it integrates quantitative grammars of water use (relating water exchange to societal and ecosystems organization) and qualitative methods (discourse analysis). This work presents the first case study focused at a river basin extent: the Upper Andarax, in South-East Spain. Water metabolism is indicated at multiple levels for ecosystems and society. To deal with the interfaces among them, relational indicators of water exploitation, water use and impact over ecosystems are used alongside policies and narratives analysis.While being a rather not intensively exploited river basin (year Water Exploitation Index~0.3 blue water,~0.15 green water), impacts over water bodies are yet important (periodic aquifer overdraft, biological degradation of the river) especially during dry season. Perceived mayor problems of water sustainability are generated by the not integration of different policies at European, national and regional scales: while the water authority establishes a compulsory reduction over water withdrawal to attend environmental flows, agricultural markets force to raise productivity increasing water demands. Adaptation strategies are divided among irrigation efficiency improvement and a reorientation of the economy towards touristic activities. Both of them entail specific trade-offs to be deemed. Aquifer-river interactions and climate change impacts are yet mayor research challenges.

  2. Soil and water conservation strategies and impact on sustainable livelihood in Cape Verde - Case study of Ribeira Seca watershed

    Science.gov (United States)

    Baptista, I.; Ferreira, A. D.; Tavares, J.; Querido, A. L. E.; Reis, A. E. A.; Geissen, V.; Ritsema, C.; Varela, A.

    2012-04-01

    Cape Verde, located off the coast of Senegal in western Africa, is a volcanic archipelago where a combination of human, climatic, geomorphologic and pedologic factors has led to extensive degradation of the soils. Like other Sahelian countries, Cape Verde has suffered the effects of desertification through the years, threatening the livelihood of the islands population and its fragile environment. In fact, the steep slopes in the ore agricultural islands, together with semi-arid and arid environments, characterized by an irregular and poorly distributed rainy season, with high intensity rainfall events, make dryland production a challenge. To survive in these fragile conditions, the stabilization of the farming systems and the maintenance of sustainable yields have become absolute priorities, making the islands an erosion control laboratory. Soil and water conservation strategies have been a centerpiece of the government's agricultural policies for the last half century. Aiming to maintain the soil in place and the water inside the soil, the successive governments of Cape Verde have implemented a number of soil and water conservation techniques, the most common ones being terraces, half moons, live barriers, contour rock walls, contour furrows and microcatchments, check dams and reforestation with drought resistant species. The soil and water conservation techniques implemented have contributed to the improvement of the economical and environmental conditions of the treated landscape, making crop production possible, consequently, improving the livelihood of the people living on the islands. In this paper, we survey the existing soil and water conservation techniques, analyze their impact on the livelihood condition of the population through a thorough literature review and field monitoring using a semi-quantitative methodology and evaluate their effectiveness and impact on crop yield in the Ribeira Seca watershed. A brief discussion is given on the cost and

  3. A water harvesting model for optimizing rainwater harvesting in the wadi Oum Zessar watershed, Tunisia

    NARCIS (Netherlands)

    Adham, Ammar; Wesseling, Jan G.; Riksen, Michel; Ouessar, Mohamed; Ritsema, Coen J.

    2016-01-01

    Rainwater harvesting (RWH) techniques have been adapted in arid and semi-arid regions to minimise the risk from droughts. The demand for water has increased but water resources have become scarcer, so the assessment and modelling of surface water related to RWH in catchments has become a

  4. Changing perceptions of watershed management from a retrospective viewpoint

    Science.gov (United States)

    Daniel G. Neary

    2000-01-01

    Watershed management, an ancient concept, was defined in Vedic texts from India that date from 1,000 B.C. This concept has been an integral part of forest and rangeland management in North America throughout the 20th century, but its scope has broadened significantly. Although the Forest Reserve Act of 1891 created the reserves that were to become the core of the...

  5. Effective Use of Time-Series Data to Calibrate a Coupled Ground Water/Surface Water Model in a Small Headwater Watershed, Northern Wisconsin

    Science.gov (United States)

    Walker, J. F.; Hunt, R. J.; Doherty, J.

    2007-12-01

    A major focus of the U.S. Geological Survey's Trout Lake Water, Energy and Biogeochemical Budgets (WEBB) project is the development of a watershed model to allow predictions of hydrologic response to future conditions including land-use and climate change. Because of the highly conductive nature of the outwash sand aquifer and the topography of the watershed, stream flow is dominated by groundwater contributions; however, runoff does occur during intense rainfall periods and spring snowmelt. The coupled ground water/surface water model GSFLOW was chosen because it could easily incorporate an existing ground-water flow model and provides for simulation of surface-water processes. Data collected from 1992 to 2006 in the study area include lake levels, ground-water levels and streamflow. The frequency of data collection varies from monthly to daily; in general the more frequent data was collected over a shorter period and during the latter portion of the period monitored. The time-series processing software TSPROC (Doherty, 2003) was used to distill the large time-series data set to a smaller set of observations and summary statistics that captured the salient hydrologic information. The TSPROC software was also used to process model output, thus providing equivalent comparisons of modeled and observed variables. Calibration targets for lake and ground-water levels included the mean and range for the entire simulation period as well as incremental differences in monthly measurements. For wells with daily water levels, the time series was first smoothed with a digital filter and then resampled at the middle of each month. Targets for streamflow included monthly volumes, comparison of points on the flow-duration curve, and total streamflow smoothed with a digital filter and then resampled at specific dates to capture the inherent variability of the observed time series. Baseflow separation was also carried out using a recursive digital filter to separate the quick

  6. Hydrogeologic framework, groundwater movement, and water budget in the Puyallup River Watershed and vicinity, Pierce and King Counties, Washington

    Science.gov (United States)

    Welch, Wendy B.; Johnson, Kenneth H.; Savoca, Mark E.; Lane, Ron C.; Fasser, Elisabeth T.; Gendaszek, Andrew S.; Marshall, Cameron; Clothier, Burt G.; Knoedler, Eric N.

    2015-01-01

    This report presents information used to characterize the groundwater-flow system in the Puyallup River Watershed and vicinity, and includes descriptions of the geology and hydrogeologic framework; groundwater recharge and discharge; groundwater levels and flow directions; seasonal groundwater level fluctuations; interactions between aquifers and the surface-water system; and a water budget. The study area covers about 1,220 square miles in northern Pierce and southern King Counties, Washington; extends north to the Green River and Auburn Valley and southwest to the Puyallup River and adjacent uplands; and is bounded on the south and east by foothills of the Cascade Range and on the west by Puget Sound. The area is underlain by a northwest-thickening sequence of unconsolidated glacial and interglacial deposits, which overlie sedimentary and volcanic bedrock units that crop out in the foothills along the southern and eastern margin of the study area. Geologic units were grouped into 13 hydrogeologic units consisting of aquifers, confining units, and an underlying bedrock unit. A surficial hydrogeologic unit map was developed and used with well information from 1,012 drillers’ logs to construct 8 hydrogeologic sections, and unit extent and thickness maps.

  7. Climate and topographic controls on simulated pasture production in a semiarid Mediterranean watershed with scattered tree cover

    Science.gov (United States)

    Lozano-Parra, J.; Maneta, M. P.; Schnabel, S.

    2014-04-01

    Natural grasses in semiarid rangelands constitute an effective protection against soil erosion and degradation, are a source of natural food for livestock and play a critical role in the hydrologic cycle by contributing to the uptake and transpiration of water. However, natural pastures are threatened by land abandonment and the consequent encroachment of shrubs and trees as well as by changing climatic conditions. In spite of their ecological and economic importance, the spatiotemporal variations of pasture production at the decadal-century scales over whole watersheds are poorly known. We used a physically based, spatially distributed ecohydrologic model applied to a 99.5 ha semiarid watershed in western Spain to investigate the sensitivity of pasture production to climate variability. The ecohydrologic model was run using a 300-year-long synthetic daily climate data set generated using a stochastic weather generator. The data set reproduced the range of climatic variations observed under the current climate. Results indicated that variation of pasture production largely depended on factors that also determined the availability of soil moisture such as the temporal distribution of precipitation, topography, and tree canopy cover. The latter is negatively related with production, reflecting the importance of rainfall and light interception, as well as water consumption by trees. Valley bottoms and flat areas in the lower parts of the catchment are characterized by higher pasture production but more interannual variability. A quantitative assessment of the quality of the simulations showed that ecohydrologic models are a valuable tool to investigate long-term (century scale) water and energy fluxes, as well as vegetation dynamics, in semiarid rangelands.

  8. Water, Energy and Carbon Balance Research: Recovery Trajectories For Oil Sands Reclamation and Disturbed Watersheds in the Western Boreal Forest

    Science.gov (United States)

    Petrone, R. M.; Carey, S. K.

    2014-12-01

    The Oil Sand Region (OSR) of North-Central Alberta exists within the sub-humid Boreal Plains (BP) ecozone, with a slight long-term moisture deficit regime. Despite this deficit, the BP is comprised of productive wetland and mixed wood (aspen and conifer dominated) forests. Reclamation activities are now underway at a large number of surface mining operations in the OSR, where target ecosystems are identified, soil prescriptions placed and commercial forest species planted. Some watersheds have been created that now contain wetlands. However, recent work in the BP suggests that over time wetlands supply moisture for the productivity of upland forests. Thus, water use of reclaimed forests is going to be critical in determining the sustainability of these systems and adjacent wetlands, and whether in time, either will achieve some form of equivalent capability that will allow for certification by regulators. A critical component in the success of any reclamation is that sufficient water is available to support target ecosystems through the course of natural climate cycles in the region. Water Use Efficiency (WUE), which links photosynthesis (GEP) with water use (Evapotranspiration (ET)), provides a useful metric to compare ecosystems and evaluate their utilization of resources. In this study, 41 site years of total growing season water and carbon flux data over 8 sites (4 reclamation, 4 regeneration) were evaluated using eddy covariance micrometeorological towers. WUE shows clear discrimination among ecosystem types as aspen stands assimilate more carbon per unit weight of water than conifers. WUEs also change with time as ecosystems become more effective at transpiring water through plant pathways compared with bare-soil evaporation, which allows an assessment of ability to limit water loss without carbon uptake. In addition, clonal rooting systems allow aspen forests to recover quicker after disturbance than reclamation sites in terms of their WUE. For reclamation

  9. Application of the Soil and Water Assessment Tool (SWAT Model on a small tropical island (Great River Watershed, Jamaica as a tool in Integrated Watershed and Coastal Zone Management

    Directory of Open Access Journals (Sweden)

    Orville P. Grey

    2014-09-01

    Full Text Available The Great River Watershed, located in north-west Jamaica, is critical for development, particularly for housing, tourism, agriculture, and mining. It is a source of sediment and nutrient loading to the coastal environment including the Montego Bay Marine Park. We produced a modeling framework using the Soil and Water Assessment Tool (SWAT and GIS. The calculated model performance statistics for high flow discharge yielded a Nash-Sutcliffe Efficiency (NSE value of 0.68 and a R² value of 0.70 suggesting good measured and simulated (calibrated discharge correlation. Calibration and validation results for streamflow were similar to the observed streamflows. For the dry season the simulated urban landuse scenario predicted an increase in surface runoff in excess of 150%. During the wet season it is predicted to range from 98 to 234% presenting a significant risk of flooding, erosion and other environmental issues. The model should be used for the remaining 25 watersheds in Jamaica and elsewhere in the Caribbean. The models suggests that projected landuse changes will have serious impacts on available water (streamflow, stream health, potable water treatment, flooding and sensitive coastal ecosystems.

  10. A Quantitative Method for Long-Term Water Erosion Impacts on Productivity with a Lack of Field Experiments: A Case Study in Huaihe Watershed, China

    Directory of Open Access Journals (Sweden)

    Degen Lin

    2016-07-01

    Full Text Available Water erosion causes reduced farmland productivity, and with a longer period of cultivation, agricultural productivity becomes increasingly vulnerable. The vulnerability of farmland productivity needs assessment due to long-term water erosion. The key to quantitative assessment is to propose a quantitative method with water loss scenarios to calculate productivity losses due to long-term water erosion. This study uses the agricultural policy environmental extender (APEX model and the global hydrological watershed unit and selects the Huaihe River watershed as a case study to describe the methodology. An erosion-variable control method considering soil and water conservation measure scenarios was used to study the relationship between long-term erosion and productivity losses and to fit with 3D surface (to come up with three elements, which are time, the cumulative amount of water erosion and productivity losses to measure long-term water erosion. Results showed that: (1 the 3D surfaces fit significantly well; fitting by the 3D surface can more accurately reflect the impact of long-term water erosion on productivity than fitting by the 2D curve (to come up with two elements, which are water erosion and productivity losses; (2 the cumulative loss surface can reflect differences in productivity loss caused by long-term water erosion.

  11. Modeling the relationship between landscape characteristics and water quality in a typical highly intensive agricultural small watershed, Dongting lake basin, south central China.

    Science.gov (United States)

    Li, Hongqing; Liu, Liming; Ji, Xiang

    2015-03-01

    Understanding the relationship between landscape characteristics and water quality is critically important for estimating pollution potential and reducing pollution risk. Therefore, this study examines the relationship between landscape characteristics and water quality at both spatial and temporal scales. The study took place in the Jinjing River watershed in 2010; seven landscape types and four water quality pollutions were chosen as analysis parameters. Three different buffer areas along the river were drawn to analyze the relationship as a function of spatial scale. The results of a Pearson's correlation coefficient analysis suggest that "source" landscape, namely, tea gardens, residential areas, and paddy lands, have positive effects on water quality parameters, while forests exhibit a negative influence on water quality parameters because they represent a "sink" landscape and the sub-watershed level is identified as a suitable scale. Using the principal component analysis, tea gardens, residential areas, paddy lands, and forests were identified as the main landscape index. A stepwise multiple regression analysis was employed to model the relationship between landscape characteristics and water quality for each season. The results demonstrate that both landscape composition and configuration affect water quality. In summer and winter, the landscape metrics explained approximately 80.7 % of the variance in the water quality variables, which was higher than that for spring and fall (60.3 %). This study can help environmental managers to understand the relationships between landscapes and water quality and provide landscape ecological approaches for water quality control and land use management.

  12. Water quality and hydrology of the Lac Vieux Desert watershed, Gogebic County, Michigan, and Vilas County, Wisconsin, 2002-04

    Science.gov (United States)

    Weaver, T.L.; Neff, B.P.; Ellis, J.M.

    2005-01-01

    Lac Vieux Desert is a prominent 6.6 square-mile lake that straddles the Michigan-Wisconsin border and forms the headwaters of the Wisconsin River. For generations, the Lac Vieux Desert Band of Lake Superior Chippewa Indians have used Lac Vieux Desert and the surrounding area for growing and harvesting wild rice, and hunting and fishing. The Lac Vieux Desert Band is concerned about the impact of lake-stage regulation on hydrology and ecology, and the impact on water quality of development along and near the shore, and recreational watercraft use and sport fishing. In 2005, the U.S. Geological Survey completed a water-resources investigation of the Lac Vieux Desert watershed in cooperation with the Lac Vieux Desert Band of Lake Superior Chippewa Indians.Water quality of Lac Vieux Desert is typical of many lakes in the northern United States. Trophic State Index calculations classify Lac Vieux Desert as a highly productive eutrophic lake. The pH of water in Lac Vieux Desert ranged from 6.5 to 9.5, and specific conductance ranged from 62 to 114 µs/cm. Chloride concentration was less than 1.5 mg/L, indicating little effect from septic-tank or road-salt input. Results indicate that the water can be classified as soft, with hardness concentrations reported as calcium carbonate ranging from 29 to 49 mg/L. Concentrations of calcium, magnesium, chloride, and other dissolved solids ranged from 47 to 77 mg/L. Alkalinity of Lac Vieux Desert ranged from 27 to 38 mg/L.Pervasive aquatic blooms, including a bloom noted during the September 2003 sampling, are apparently common in late summer. Biological productivity at Lac Vieux Desert does not appear to have changed appreciably between 1973 and 2004. In the current study, total phosphorus concentrations ranged from 0.01 to 0.064 mg/L and dissolved nitrite plus nitrate nitrogen concentrations ranged from at, or below detection limit to 0.052 mg/L. Overabundance of nutrients in Lac Vieux Desert, particularly nitrogen and phosphorus

  13. Artificial intelligent techniques for optimizing water allocation in a reservoir watershed

    Science.gov (United States)

    Chang, Fi-John; Chang, Li-Chiu; Wang, Yu-Chung

    2014-05-01

    This study proposes a systematical water allocation scheme that integrates system analysis with artificial intelligence techniques for reservoir operation in consideration of the great uncertainty upon hydrometeorology for mitigating droughts impacts on public and irrigation sectors. The AI techniques mainly include a genetic algorithm and adaptive-network based fuzzy inference system (ANFIS). We first derive evaluation diagrams through systematic interactive evaluations on long-term hydrological data to provide a clear simulation perspective of all possible drought conditions tagged with their corresponding water shortages; then search the optimal reservoir operating histogram using genetic algorithm (GA) based on given demands and hydrological conditions that can be recognized as the optimal base of input-output training patterns for modelling; and finally build a suitable water allocation scheme through constructing an adaptive neuro-fuzzy inference system (ANFIS) model with a learning of the mechanism between designed inputs (water discount rates and hydrological conditions) and outputs (two scenarios: simulated and optimized water deficiency levels). The effectiveness of the proposed approach is tested on the operation of the Shihmen Reservoir in northern Taiwan for the first paddy crop in the study area to assess the water allocation mechanism during drought periods. We demonstrate that the proposed water allocation scheme significantly and substantially avails water managers of reliably determining a suitable discount rate on water supply for both irrigation and public sectors, and thus can reduce the drought risk and the compensation amount induced by making restrictions on agricultural use water.

  14. Spatial Distribution of Ground-Water Recharge Estimated with a Water-Budget Method for the Jordan Creek Watershed, Lehigh County, Pennsylvania

    Science.gov (United States)

    Risser, Dennis W.

    2008-01-01

    This report presents the results of a study by the U.S. Geological Survey, in cooperation with the Pennsylvania Geological Survey, to illustrate a water-budget method for mapping the spatial distribution of ground-water recharge for a 76-square-mile part of the Jordan Creek watershed, northwest of Allentown, in Lehigh County, Pennsylvania. Recharge was estimated by using the Hydrological Evaluation of Landfill Performance (HELP) water-budget model for 577 landscape units in Jordan Creek watershed, delineated on the basis of their soils, land use/land cover, and mean annual precipitation during 1951-2000. The water-budget model routes precipitation falling on each landscape unit to components of evapotranspiration, surface runoff, storage, and vertical percolation (recharge) for a five-layer soil column on a daily basis. The spatial distribution of mean annual recharge during 1951-2000 for each landscape unit was mapped by the use of a geographic information system. Recharge simulated by the water-budget model in Jordan Creek watershed during 1951-2000 averaged 12.3 inches per year and ranged by landscape unit from 0.11 to 17.05 inches per year. Mean annual recharge during 1951-2000 simulated by the water-budget model was most sensitive to changes to input values for precipitation and runoff-curve number. Mean annual recharge values for the crop, forest, pasture, and low-density urban land-use/land-cover classes were similar (11.2 to 12.2 inches per year) but were substantially less for high-density urban (6.8 inches per year), herbaceous wetlands (2.5 inches per year), and forested wetlands (1.3 inches per year). Recharge rates simulated for the crop, forest, pasture, and low-density urban land-cover classes were similar because those land-use/land-cover classes are represented in the model with parameter values that either did not significantly affect simulated recharge or tended to have offsetting effects on recharge. For example, for landscapes with forest land

  15. Evaluation of Surface Water Harvesting Potential in Aq Emam Watershed System in the Golestan Province

    OpenAIRE

    s. nazaryan; A. Najafinejad; N. Nura

    2016-01-01

    Introduction : Given its low and sparse precipitation both in spatial and temporal scales, Iran is nestled in an arid and semiarid part of the world. On the other hand, because of population growth, urbanization and the development of agriculture and industry sector is frequently encountered with increasing water demand. The increasing trend of water demand will widen the gap between water supply and demand in the future. This, in turn, necessitates urgent attention to the fundamentals of eco...

  16. Empirical streamflow simulation for water resource management in data-scarce seasonal watersheds

    Science.gov (United States)

    Shortridge, J. E.; Guikema, S. D.; Zaitchik, B. F.

    2015-10-01

    In the past decade, certain methods for empirical rainfall-runoff modeling have seen extensive development and been proposed as a useful complement to physical hydrologic models, particularly in basins where data to support process-based models is limited. However, the majority of research has focused on a small number of methods, such as artificial neural networks, despite the development of multiple other approaches for non-parametric regression in recent years. Furthermore, this work has generally evaluated model performance based on predictive accuracy alone, while not considering broader objectives such as model interpretability and uncertainty that are important if such methods are to be used for planning and management decisions. In this paper, we use multiple regression and machine-learning approaches to simulate monthly streamflow in five highly-seasonal rivers in the highlands of Ethiopia and compare their performance in terms of predictive accuracy, error structure and bias, model interpretability, and uncertainty when faced with extreme climate conditions. While the relative predictive performance of models differed across basins, data-driven approaches were able to achieve reduced errors when compared to physical models developed for the region. Methods such as random forests and generalized additive models may have advantages in terms of visualization and interpretation of model structure, which can be useful in providing insights into physical watershed function. However, the uncertainty associated with model predictions under climate change should be carefully evaluated, since certain models (especially generalized additive models and multivariate adaptive regression splines) became highly variable when faced with high temperatures.

  17. The influence of land-use patterns in the Ruvu river watershed on water quality in the river system

    Science.gov (United States)

    Ngoye, Elizabeth; Machiwa, John F.

    This work assessed the impacts of land-use patterns in the Ruvu river basin on water quality in the river system. Seasonal changes in water quality parameters were also investigated. Ten river water-sampling stations were selected and samples were collected and analysed according to standard analytical procedures. The results showed that physico-chemical parameters of river water ranged as follows: pH, from 6.95 ± 0.09 to 8.07 ± 0.23; temperature, from 14.0 ± 0.06 to 31.1 ± 0.4 °C; EC, from 39.8 ± 0.8 to 48,734 306 μs/cm; TDS, from 19.9 ± 0.4 to 24,367 ± 152.9 mg/l; turbidity, from 3.0 ± 0.6 to 840 ± 69.3 NTU and DO, from 6.8 ± 0.02 to 16.78 mg/l. The ranges for nutrient concentrations were NO 3-N, from 0.006 ± 0.0003 to 0.62 ± 0.3 mg/l; NH 4-N, from 0.34 ± 0.17 to 16.2 ± 0.5 mg/l; PO 4-P, from 0.009 ± 0.001 to 1.75 ± 0.2 mg/l and TP, from 0.02 ± 0.003 to 3.56 ± 0.38 mg/l. Generally, water samples from stations with forested catchments had high levels of DO and low levels of NH 4-N and NO 3-N compared to those from farmland, industrial, residential and market places. There were clear seasonal variations showing an increase in the concentrations of nutrients during rainy season. The results show impairment of the water quality of the river by anthropogenic activities in the catchment. Water pollution prevention strategies to ensure prevention of pollution and protection of water resources in the Ruvu river watershed are recommended.

  18. Technical review of managed underground storage of water study of the upper Catherine Creek watershed, Union County, northeastern Oregon

    Science.gov (United States)

    Snyder, Daniel T.

    2014-01-01

    Because of water diversions during summer, flow in Catherine Creek, a tributary to the Grande Ronde River in northeastern Oregon, is insufficient to sustain several aquatic species for which the stream is listed as critical habitat. A feasibility study for managed underground storage (MUS) in the upper Catherine Creek watershed in Union County, Oregon, was undertaken by Anderson Perry and Associates, Inc., to address the issue of low flows in summer. The results of the study were released as a report titled “Upper Catherine Creek Storage Feasibility Study for Grande Ronde Model Watershed,” which evaluated the possibility of diverting Catherine Creek streamflow during winter (when stream discharge is high), storing the water by infiltration or injection into an aquifer adjacent to the stream, and discharging the water back to the stream in summer to augment low flows. The method of MUS would be accomplished using either (1) aquifer storage and recovery (ASR) that allows for the injection of water that meets drinking-water-quality standards into an aquifer for later recovery and use, or (2) artificial recharge (AR) that involves the intentional addition of water diverted from another source to a groundwater reservoir. Concerns by resource managers that the actions taken to improve water availability for upper Catherine Creek be effective, cost-efficient, long-term, and based on sound analysis led the National Fish and Wildlife Foundation to request that the U.S. Geological Survey conduct an independent review and evaluation of the feasibility study. This report contains the results of that review. The primary objectives of the Anderson Perry and Associates study reviewed here included (1) identifying potentially fatal flaws with the concept of using AR and (or) ASR to augment the streamflow of Catherine Creek, (2) identifying potentially favorable locations for augmenting streamflow, (3) developing and evaluating alternatives for implementing AR and (or) ASR, and

  19. Assessment of the water quality monitoring network of the Piabanha River experimental watersheds in Rio de Janeiro, Brazil, using autoassociative neural networks.

    Science.gov (United States)

    Villas-Boas, Mariana D; Olivera, Francisco; de Azevedo, Jose Paulo S

    2017-09-01

    Water quality monitoring is a complex issue that requires support tools in order to provide information for water resource management. Budget constraints as well as an inadequate water quality network design call for the development of evaluation tools to provide efficient water quality monitoring. For this purpose, a nonlinear principal component analysis (NLPCA) based on an autoassociative neural network was performed to assess the redundancy of the parameters and monitoring locations of the water quality network in the Piabanha River watershed. Oftentimes, a small number of variables contain the most relevant information, while the others add little or no interpretation to the variability of water quality. Principal component analysis (PCA) is widely used for this purpose. However, conventional PCA is not able to capture the nonlinearities of water quality data, while neural networks can represent those nonlinear relationships. The results presented in this work demonstrate that NLPCA performs better than PCA in the reconstruction of the water quality data of Piabanha watershed, explaining most of data variance. From the results of NLPCA, the most relevant water quality parameter is fecal coliforms (FCs) and the least relevant is chemical oxygen demand (COD). Regarding the monitoring locations, the most relevant is Poço Tarzan (PT) and the least is Parque Petrópolis (PP).

  20. Modeling sedimentation-filtration basins for urban watersheds using Soil and Water Assessment Tool

    Science.gov (United States)

    Sedimentation-filtration (SedFil) basins are one of the storm-water best management practices (BMPs) that are intended to mitigate water quality problems in urban creeks and rivers. A new physically based model of variably saturated flows was developed for simulating flow and sediment in SedFils wi...

  1. Pre- and postfire distribution of soil water repellency in a steep chaparral watershed

    Science.gov (United States)

    K. R. Hubbert; P. M. Wohlgemuth; H. K. Preisler

    2008-01-01

    The development and nature of water repellent soils and their spatial distribution on the landscape are not well understood relative to evaluating hillslope response to fire. Soil water repellency is particularly common in chaparral communities, due in part to the coarse-textured soils, and the high resin content of the organic litter. Objectives of this study were 1)...

  2. A Multi-Satellite Approach for Water Storage Monitoring in an Arid Watershed

    Directory of Open Access Journals (Sweden)

    Dawit T. Ghebreyesus

    2016-07-01

    Full Text Available The objective of this study was to use satellite imagery to monitor the water budget of Al Ain region in the United Arab Emirates (UAE. Inflows and outflows were estimated and the trend of water storage variation in the study area was examined from 2005 to 2014. Evapotranspiration was estimated using the simplified Penman-Monteith equation. Landsat images were used to determine the extent of agricultural and green areas. Time series of gravity recovery and climate experiment (GRACE observations over the study area were used to assess the inferred water storage variation from satellite data. The change of storage inferred from the Water Budget Equation showed a decreasing trend at an average rate of 2.57 Mm3 annually. Moreover, GRACE readings showed a decreasing trend at a rate of 0.35 cm of water depth annually. Mann-Kendal, a non-parametric trend test, proved the presence of significant negative trends in both time series at a 5% significance level. A two-month lag resulted in a better agreement (R2 = 0.55 between the change in water storage and GRACE anomalies within the study area. These results suggest that water storage in the study area is being depleted significantly. Moreover, the potential of remote sensing in water resource management, especially in remote and arid areas, was demonstrated.

  3. Integrating GIS, remote sensing and mathematical modelling for surface water quality management in irrigated watersheds

    NARCIS (Netherlands)

    Azab, A.M.

    2012-01-01

    The intensive uses of limited water resources, the growing population rates and the various increasing human activities put high and continuous stresses on these resources. Major problems affecting the water quality of rivers, streams and lakes may arise from inadequately treated sewage, poor land

  4. Water Balance to Recharge Calculation: Implications for Watershed Management Using Systems Dynamics Approach

    Directory of Open Access Journals (Sweden)

    Ramesh Dhungel

    2016-03-01

    Full Text Available Groundwater depletion in the face of growth is a well-known problem, particularly in those areas that have grown to become dependent on a declining resource. This research comprises a broad synthesis of existing water resources data, to understand the long-term implications of continued growth in water demand on groundwater dominant water resources, and to develop a tool for sustainable water management. The Palouse region of Washington and Idaho, USA. (approximately 60,000 people in a rural setting is entirely dependent on groundwater from two basalt aquifers for potable water. Using the systems dynamics approach and a water balance that considered the entire hydrologic cycle, a hydrologic model of these aquifers was developed, tested and applied to simulate their behavior over a 150 year time period assuming the current infrastructure does not change. With 1% population growth and current water extraction rates, the results indicated the upper aquifer use may be sustainable, while the lower aquifer use is likely unsustainable in the long term. This study also shows that uncertainties in key aspects of the system create limitations to groundwater management.

  5. Surface-water and karst groundwater interactions and streamflow-response simulations of the karst-influenced upper Lost River watershed, Orange County, Indiana

    Science.gov (United States)

    Bayless, E. Randall; Cinotto, Peter J.; Ulery, Randy L.; Taylor, Charles J.; McCombs, Gregory K.; Kim, Moon H.; Nelson, Hugh L.

    2014-01-01

    The U.S. Geological Survey (USGS), in cooperation with the U.S. Army Corps of Engineers (USACE) and the Indiana Office of Community and Rural Affairs (OCRA), conducted a study of the upper Lost River watershed in Orange County, Indiana, from 2012 to 2013. Streamflow and groundwater data were collected at 10 data-collection sites from at least October 2012 until April 2013, and a preliminary Water Availability Tool for Environmental Resources (WATER)-TOPMODEL based hydrologic model was created to increase understanding of the complex, karstic hydraulic and hydrologic system present in the upper Lost River watershed, Orange County, Ind. Statistical assessment of the optimized hydrologic-model results were promising and returned correlation coefficients for simulated and measured stream discharge of 0.58 and 0.60 and Nash-Sutcliffe efficiency values of 0.56 and 0.39 for USGS streamflow-gaging stations 03373530 (Lost River near Leipsic, Ind.), and 03373560 (Lost River near Prospect, Ind.), respectively. Additional information to refine drainage divides is needed before applying the model to the entire karst region of south-central Indiana. Surface-water and groundwater data were used to tentatively quantify the complex hydrologic processes taking place within the watershed and provide increased understanding for future modeling and management applications. The data indicate that during wet-weather periods and after certain intense storms, the hydraulic capacity of swallow holes and subsurface conduits is overwhelmed with excess water that flows onto the surface in dry-bed relic stream channels and karst paleovalleys. Analysis of discharge data collected at USGS streamflow-gaging station 03373550 (Orangeville Rise, at Orangeville, Ind.), and other ancillary data-collection sites in the watershed, indicate that a bounding condition is likely present, and drainage from the underlying karst conduit system is potentially limited to near 200 cubic feet per second. This

  6. Selenium Speciation in the Fountain Creek Watershed (Colorado, USA Correlates with Water Hardness, Ca and Mg Levels

    Directory of Open Access Journals (Sweden)

    James S. Carsella

    2017-04-01

    Full Text Available The environmental levels of selenium (Se are regulated and strictly enforced by the Environmental Protection Agency (EPA because of the toxicity that Se can exert at high levels. However, speciation plays an important role in the overall toxicity of Se, and only when speciation analysis has been conducted will a detailed understanding of the system be possible. In the following, we carried out the speciation analysis of the creek waters in three of the main tributaries—Upper Fountain Creek, Monument Creek and Lower Fountain Creek—located in the Fountain Creek Watershed (Colorado, USA. There are statistically significant differences between the Se, Ca and Mg, levels in each of the tributaries and seasonal swings in Se, Ca and Mg levels have been observed. There are also statistically significant differences between the Se levels when grouped by Pierre Shale type. These factors are considered when determining the forms of Se present and analyzing their chemistry using the reported thermodynamic relationships considering Ca2+, Mg2+, SeO42−, SeO32− and carbonates. This analysis demonstrated that the correlation between Se and water hardness can be explained in terms of formation of soluble CaSeO4. The speciation analysis demonstrated that for the Fountain Creek waters, the Ca2+ ion may be mainly responsible for the observed correlation with the Se level. Considering that the Mg2+ level is also correlating linearly with the Se levels it is important to recognize that without Mg2+ the Ca2+ would be significantly reduced. The major role of Mg2+ is thus to raise the Ca2+ levels despite the equilibria with carbonate and other anions that would otherwise decrease Ca2+ levels.

  7. Selenium Speciation in the Fountain Creek Watershed (Colorado, USA) Correlates with Water Hardness, Ca and Mg Levels.

    Science.gov (United States)

    Carsella, James S; Sánchez-Lombardo, Irma; Bonetti, Sandra J; Crans, Debbie C

    2017-04-30

    The environmental levels of selenium (Se) are regulated and strictly enforced by the Environmental Protection Agency (EPA) because of the toxicity that Se can exert at high levels. However, speciation plays an important role in the overall toxicity of Se, and only when speciation analysis has been conducted will a detailed understanding of the system be possible. In the following, we carried out the speciation analysis of the creek waters in three of the main tributaries-Upper Fountain Creek, Monument Creek and Lower Fountain Creek-located in the Fountain Creek Watershed (Colorado, USA). There are statistically significant differences between the Se, Ca and Mg, levels in each of the tributaries and seasonal swings in Se, Ca and Mg levels have been observed. There are also statistically significant differences between the Se levels when grouped by Pierre Shale type. These factors are considered when determining the forms of Se present and analyzing their chemistry using the reported thermodynamic relationships considering Ca 2+ , Mg 2+ , SeO₄ 2- , SeO₃ 2- and carbonates. This analysis demonstrated that the correlation between Se and water hardness can be explained in terms of formation of soluble CaSeO₄. The speciation analysis demonstrated that for the Fountain Creek waters, the Ca 2+ ion may be mainly responsible for the observed correlation with the Se level. Considering that the Mg 2+ level is also correlating linearly with the Se levels it is important to recognize that without Mg 2+ the Ca 2+ would be significantly reduced. The major role of Mg 2+ is thus to raise the Ca 2+ levels despite the equilibria with carbonate and other anions that would otherwise decrease Ca 2+ levels.

  8. USDA-ARS Riesel Watersheds, Riesel, Texas, USA: Water quality research database

    National Research Council Canada - National Science Library

    R Daren Harmel; Richard L Haney; Douglas R Smith; Michael White; Kevin W King

    2014-01-01

    ... (www.nrrig.mwa.ars.usda.gov/stewards/stewards.html). In addition, water quality data including dissolved inorganic N and P compounds measured from more than 1000 storm runoff events, 1300 base flow sampling events...

  9. Climate Change and Coastal Watersheds: Adaptation to Attain Clean Water Goals and Sustainable Coasts

    Science.gov (United States)

    The Clean Water Act contains a mandate to control pollution, to improve estuary habitat, to ensure healthy plant and animal communities, and to maintain human uses. This document highlights ways to meet these goals while adapting to climate impacts.

  10. USDA‐ARS Riesel Watersheds, Riesel, Texas, USA: Water quality research database

    National Research Council Canada - National Science Library

    Harmel, R. Daren; Haney, Richard L; Smith, Douglas R; White, Michael; King, Kevin W

    2014-01-01

    ... ( www.nrrig.mwa.ars.usda.gov/stewards/stewards.html ). In addition, water quality data including dissolved inorganic N and P compounds measured from more than 1000 storm runoff events, 1300 base flow sampling events...

  11. Trophic state of water in the watershed of Lake Mirim, RS, Brazil

    Directory of Open Access Journals (Sweden)

    Orlando Pereira-Ramirez

    2009-04-01

    Full Text Available The objective of this work was to analyze the spacetime variations in the trophic characteristics of the principal water bodies feeding Lake Mirim, in the state of Rio Grande do Sul, by determination of the Trophic State Index proposed by Toledo Jr. (IETT and Lamparelli (IETL, to assess water quality data between 1996 and 1998. It was verified that the lotic environments presented greater eutrophication conditions when evaluated by the Toledo Jr. methodology, in which the IETT varied from Eutrophic to Hypereutrophic. However, the evaluated environments showed variations from Mesotrophic to Hypereutrophic for the IETL when evaluated according to the Lamparelli methodology. From the classification proposed by Toledo Jr., lentic water bodies were considered Mesotrophic (IETT > 44 and Hypereutrophic (IETT > 74, while the Lamparelli method classified them as Eutrophic (IETL > 59 and Hypereutrophic (IETL > 67. Concentrations of phosphorus encountered in all water samples were greater than the limits established by the CONAMA Resolution n. 357, 2005, for class 2 water bodies, probably due to the discharge of untreated domestic and industrial wastes into the waters.

  12. Watershed hydrology. Chapter 7.

    Science.gov (United States)

    Elons S. Verry; Kenneth N. Brooks; Dale S. Nichols; Dawn R. Ferris; Stephen D. Sebestyen

    2011-01-01

    Watershed hydrology is determined by the local climate, land use, and pathways of water flow. At the Marcell Experimental Forest (MEF), streamflow is dominated by spring runoff events driven by snowmelt and spring rains common to the strongly continental climate of northern Minnesota. Snowmelt and rainfall in early spring saturate both mineral and organic soils and...

  13. Modeling Sustainability of Water, Environment, Livelihood, and Culture in Traditional Irrigation Communities and Their Linked Watersheds

    Directory of Open Access Journals (Sweden)

    Kenneth Boykin

    2012-11-01

    Full Text Available Water scarcity, land use conversion and cultural and ecosystem changes threaten the way of life for traditional irrigation communities of the semi-arid southwestern United States. Traditions are strong, yet potential upheaval is great in these communities that rely on acequia irrigation systems. Acequias are ancient ditch systems brought from the Iberian Peninsula to the New World over 400 years ago; they are simultaneously gravity flow water delivery systems and shared water governance institutions. Acequias have survived periods of drought and external shocks from changing economics, demographics, and resource uses. Now, climate change and urbanization threaten water availability, ecosystem functions, and the acequia communities themselves. Do past adaptive practices hold the key to future sustainability, or are new strategies required? To explore this issue we translated disciplinary understanding into a uniform format of causal loop diagrams to conceptualize the subsystems of the entire acequia-based human-natural system. Four subsystems are identified in this study: hydrology, ecosystem, land use/economics, and sociocultural. Important linkages between subsystems were revealed as well as variables indicating community cohesion (e.g., total irrigated land, intensity of upland grazing, mutualism. Ongoing work will test the conceptualizations with field data and modeling exercises to capture tipping points for non-sustainability and thresholds for sustainable water use and community longevity.

  14. Water quality of the Apalachicola-Chattahoochee-Flint and Ocmulgee river basins related to flooding from Tropical Storm Alberto; pesticides in urban and agricultural watersheds, and nitrate and pesticides in ground water, Georgia, Alabama, and Florida

    Science.gov (United States)

    Hippe, D.J.; Wangsness, D.J.; Frick, E.A.; Garrett, J.W.

    1994-01-01

    This report presents preliminary water-quality information from three studies that are part of the National Water-Quality Assessment (NAWQA) Program in the Apalachicola-Chattahoochee-Flint (ACF) River basin and the adjacent Ocmulgee River basin. During the period July 3-7, 1994, heavy rainfall from tropical storm Alberto caused record flooding on the Ocmulgee and Flint Rivers and several of their tributaries. Much of the nitrogen load transported during the flooding was as organic nitrogen generally derived from organic detritus, rather than nitrate derived from other sources, such as fertilizer. More than half the mean annual loads of total phosphorus and organic nitrogen were trans- ported in the Flint and Ocmulgee Rivers during the flood. Fourteen herbicides, five insecticides, and one fungicide were detected in floodwaters of the Ocmulgee, Flint, and Apalachicola Rivers. In a second study, water samples were collected at nearly weekly intervals from March 1993 through April 1994 from one urban and two agricultural watersheds in the ACF River basin, and analyzed for 84 commonly used pesticides. More pesticides were detected and at generally higher concentrations in water from the urban watershed than the agricultural water- sheds, and a greater number of pesticides were persistent throughout much of the year in the urban watershed. Simazine exceeded U.S. Environmental Protection Agency (EPA) drinking-water standards in one of 57 samples from the urban watershed. In a third study, 38 wells were installed in surficial aquifers adjacent to and downgradient of farm fields within agricultural areas in the southern ACF River basin. Even though regional aquifers are generally used for irrigation and domestic- and public-water supplies, degradation of water quality in the surficial aquifers serves as an early warning of potential contamination of regional aquifers. Nitrate concentrations were less than 3 mg/L as N (indicating minimal effect of human activities) in water

  15. THE POTENTIAL OF FOREST BUFFER TO PREVENT STREAM FROM WATER POLLUTANTS:A CASE STUDY IN GROJOKAN SEWU SUB-WATERSHED, KARANGANYAR DISTRICT, CENTRAL JAVA

    Directory of Open Access Journals (Sweden)

    Nining Wahyuningrum

    2013-10-01

    Full Text Available Population growth leads to water scarcity in terms of both quality and quantity. Agricultural and urban watersheds potentially produce more pollutantsthan forested area. It is considered that forested area has potential in storing and protecting water supply in such a way that water distribution and quality can be guaranteed. The objective of  the study was to determine the relationship between the percentages of forested area in a watershed with the water quality. Thestudy was conducted in 2010in GrojokanSewu Sub-watershed, Karanganyar District, Central Java. Using GIS (Geographic Information System, this sub-watershedwas divided into four sub-sub-watershedswith different percentages of forested areas. Water samples were collected in each sub-sub-watershedto find out the relationship between the forested area and the total dissolvedsolids, turbidity, sodium, nitrite, nitrate, sulfate and organic matters. The statistical analysis indicates relationships in quadratic form between sodium, nitrite, TDS, sulfate and organic matters with the percentage of  forested area (R2=0.99, R2=0.99, R2=0.98, R2=0.95 and R2=0.77, respectively. The relationships are different from those of turbidity and nitrate that have low R2 (R2=0.28 and R2=0.36 values. It implies that the forested area is capable to reduce sodium, nitrite, TDS, sulfate and organic matters, and thus water pollutants can be reduced by forest formation as it can filter water through retention of sediments and nutrients.

  16. Factors affecting the fate and transport of glyphosate and AMPA into surface waters of agricultural watersheds in the United States and Europe

    Science.gov (United States)

    Coupe, R.; Kalkhoff, S.; Capel, P.; Gregoire, C.

    2012-04-01

    Glyphosate [N-(phosphonomethyl)glycine] is a herbicide used extensively in almost all agricultural and urban areas of the United States and Europe. Although, glyphosate is used widely throughout the world in the production of many crops, it is predominately used in the United States on soybeans, corn, potatoes, and cotton that have been genetically modified to be tolerant to glyphosate. From 1992 to 2007, the agricultural use of glyphosate has increased from less than 10,000 Mg to more than 80,000 Mg, respectively. The greatest areal use is in the midwestern United States where glyphosate is applied on transgenic corn and soybeans. Because of the difficulty and expense in analyzing for glyphosate and AMPA (aminomethylphosphonic acid, a primary glyphosate degradate) in water, there have been only small scale studies on the fate and transport of glyphosate. The characterization of the transport of glyphosate and AMPA on a watershed scale is lacking. Glyphosate and AMPA were frequently detected in the surface waters of 4 agricultural watersheds in studies conducted by the U.S. Geological Survey in the United States and at the Laboratory of Hydrology and Geochemistry of Strasbourg. Two of these basins were located in the midwestern United States where the major crops are corn and soybean, the third is located the lower Mississippi River Basin where the major crops are soybean, corn, rice, and cotton, and the fourth was located near Strasbourg, France where the use of glyphosate was on a vineyard. The load as a percent of use ranged from 0.009 to 0.86 percent and could be related to 3 factors: source strength, hydrology, and flowpath. Glyphosate use in a watershed results in some occurrence in surface water at the part per billion level; however, those watersheds most at risk for the offsite transport of glyphosate are those with high application rates, rainfall that results in overland runoff, and a flowpath that does not include transport through the soil.

  17. Spatial distribution and transport of heavy metals in soil, ponded-surface water and grass in a pb-contaminated watershed as related to land-use practices.

    Science.gov (United States)

    Panichayapichet, P; Nitisoravut, S; Simachaya, W

    2007-12-01

    The aim of this study was to investigate the spatial distribution of heavy metal in soil and evaluate the dissolution of metal from soil to ponded-surface water, leaching through soil profiles and metal uptake in grass as related to different land-use practices. The data provided a scientific basis for best-management practices for land use in Khli Ti watershed. The watershed has a Pb-contamination problem from the previous operation of a Pb-ore concentrator and abandoned Zn-Pb mine. Sampling sites were selected from a land-use map, with land-use types falling into the following four categories: forest, agricultural land, residential area and road. Soil, ponded-surface water, grass samples and soil profiles were collected. The study related soil characteristics from different land-use practices and locations with observed metal concentrations in ponded-surface water and soil. High enrichment factors of Pb and As in soil were found. Partitioning coefficient, K(d) values were in the order: Cr > Pb > Ni > Cu > Cd > Zn. Soil disturbance from land-use activities including tillage and traffic increased leaching of trace metal from soils. Pb in soil was significantly taken up by grass even though the Transfer Factor, TF values were rather low. Agricultural activities in the watershed must be limited. Moreover, land encroachments in the upper and middle part of the watershed which have high potential of Pb must be strictly controlled in order to reduce the Pb contamination from non-point sources.

  18. Stable water isotope variation in a Central Andean watershed dominated by glacier and snowmelt

    Directory of Open Access Journals (Sweden)

    N. Ohlanders

    2013-03-01

    Full Text Available Central Chile is an economically important region for which water supply is dependent on snow- and ice melt. Nevertheless, the relative contribution of water supplied by each of those two sources remains largely unknown. This study represents the first attempt to estimate the region's water balance using stable isotopes of water in streamflow and its sources. Isotopic ratios of both H and O were monitored during one year in a high-altitude basin with a moderate glacier cover (11.5%. We found that the steep altitude gradient of the studied catchment caused a corresponding gradient in snowpack isotopic composition and that this spatial variation had a profound effect on the temporal evolution of streamflow isotopic composition during snowmelt. Glacier melt and snowmelt contributions to streamflow in the studied basin were determined using a quantitative analysis of the isotopic composition of streamflow and its sources, resulting in a glacier melt contribution of 50–90% for the unusually dry melt year of 2011/2012. This suggests that in (La Niña years with little precipitation, glacier melt is an important water source for central Chile. Predicted decreases in glacier melt due to global warming may therefore have a negative long-term impact on water availability in the Central Andes. The pronounced seasonal pattern in streamflow isotope composition and its close relation to the variability in snow cover and discharge presents a potentially powerful tool to relate discharge variability in mountainous, melt-dominated catchments with related factors such as contributions of sources to streamflow and snowmelt transit times.

  19. Watershed District

    Data.gov (United States)

    Kansas Data Access and Support Center — Boundaries show on this map are derived from legal descriptions contained in petitions to the Kansas Secretary of State for the creation or extension of watershed...

  20. Rehabilitation of cheatgrass-infested rangelands: management

    Science.gov (United States)

    This is the final part of a three part series specifically addressing lessons learned concerning the management of rehabilitated cheatgrass-infested rangelands. Steve Novak and Richard Mack reported in 2003 that they found no evidence of outcrossing in 2,000 cheatgrass seedlings from 60 North Americ...

  1. Rehabilitation of cheatgrass-infested rangelands: concepts

    Science.gov (United States)

    The introduction and subsequent invasion of cheatgrass (Bromus tectorum) onto millions of acres of Intermountain West rangelands has caused astronomical changes to numerous ecosystems and the multiple uses that depend on healthy and functional ecosystems. This is the first part, of a 3-part series ...

  2. Management of Collective Rangelands in Rhamna (Morocco ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Rangelands are severely degraded in Morocco. This has stimulated public interventions to reduce the pressure on natural resources and promote sustainable management. In Rhamna, a region traditionally used for transhumance, such efforts have met with limited success because they have not taken into consideration ...

  3. Weather-centric rangeland revegetation planning

    Science.gov (United States)

    Hardegree, Stuart P.; Abatzoglou, John T.; Brunson, Mark W.; Germino, Matthew; Hegewisch, Katherine C.; Moffet, Corey A.; Pilliod, David S.; Roundy, Bruce A.; Boehm, Alex R.; Meredith, Gwendwr R.

    2018-01-01

    Invasive annual weeds negatively impact ecosystem services and pose a major conservation threat on semiarid rangelands throughout the western United States. Rehabilitation of these rangelands is challenging due to interannual climate and subseasonal weather variability that impacts seed germination, seedling survival and establishment, annual weed dynamics, wildfire frequency, and soil stability. Rehabilitation and restoration outcomes could be improved by adopting a weather-centric approach that uses the full spectrum of available site-specific weather information from historical observations, seasonal climate forecasts, and climate-change projections. Climate data can be used retrospectively to interpret success or failure of past seedings by describing seasonal and longer-term patterns of environmental variability subsequent to planting. A more detailed evaluation of weather impacts on site conditions may yield more flexible adaptive-management strategies for rangeland restoration and rehabilitation, as well as provide estimates of transition probabilities between desirable and undesirable vegetation states. Skillful seasonal climate forecasts could greatly improve the cost efficiency of management treatments by limiting revegetation activities to time periods where forecasts suggest higher probabilities of successful seedling establishment. Climate-change projections are key to the application of current environmental models for development of mitigation and adaptation strategies and for management practices that require a multidecadal planning horizon. Adoption of new weather technology will require collaboration between land managers and revegetation specialists and modifications to the way we currently plan and conduct rangeland rehabilitation and restoration in the Intermountain West.

  4. Increasing flexibility in rangeland management during drought

    Science.gov (United States)

    The extreme drought that began in 2011 and persists throughout the central and western US presents a challenge to sustainable rangeland management. Wyoming ranchers manage half of this drought-prone state and are at the forefront of this challenge. We examined Wyoming ranchers’ drought management st...

  5. EnviroAtlas - Number of Water Markets per HUC8 Watershed, U.S., 2015, Forest Trends' Ecosystem Marketplace

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset contains polygons depicting the number of watershed-level market-based programs, referred to herein as markets, in operation per 8-digit HUC...

  6. MODFLOW-NWT model used to evaluate groundwater/surface-water interactions in the Bad River Watershed, Wisconsin

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A groundwater-flow model was developed for the Bad River Watershed and surrounding area by using the U.S. Geological Survey (USGS) finite-difference code...

  7. Combined and synergistic effects of climate change and urbanization on water quality in the Wolf Bay watershed, southern Alabama.

    Science.gov (United States)

    Wang, Ruoyu; Kalin, Latif

    2018-02-01

    This study investigated potential changes in flow, total suspended solid (TSS) and nutrient (nitrogen and phosphorous) loadings under future climate change, land use/cover (LULC) change and combined change scenarios in the Wolf Bay watershed, southern Alabama, USA. Four Global Circulation Models (GCMs) under three Special Report Emission Scenarios (SRES) of greenhouse gas were used to assess the future climate change (2016-2040). Three projected LULC maps (2030) were employed to reflect different extents of urbanization in future. The individual, combined and synergistic impacts of LULC and climate change on water quantity/quality were analyzed by the Soil and Water Assessment Tool (SWAT). Under the "climate change only" scenario, monthly distribution and projected variation of TSS are expected to follow a pattern similar to streamflow. Nutrients are influenced both by flow and management practices. The variation of Total Nitrogen (TN) and Total Phosphorous (TP) generally follow the flow trend as well. No evident difference in the N:P ratio was projected. Under the "LULC change only" scenario, TN was projected to decrease, mainly due to the shrinkage of croplands. TP will increase in fall and winter. The N:P ratio shows a strong decreasing potential. Under the "combined change" scenario, LULC and climate change effect were considered simultaneously. Results indicate that if future loadings are expected to increase/decrease under any individual scenario, then the combined change will intensify that trend. Conversely, if their effects are in opposite directions, an offsetting effect occurs. Science-based management practices are needed to reduce nutrient loadings to the Bay. Copyright © 2017. Published by Elsevier B.V.

  8. A national strategy is needed to prevent the coming water war: the Mississippi River watershed shows us why

    OpenAIRE

    Wendt, Timothy J.

    2014-01-01

    Approved for public release; distribution is unlimited. The Mississippi River watershed is currently managed as six separate basins including the Missouri, Illinois, Ohio, Arkansas, and Upper and Lower Mississippi Rivers. This research pulls together several system components'navigation, flood control, environmental, municipal and industrial uses, and geopolitical concerns'and proposes treating the entire watershed as a system. The current problem is that actions taken in one basin often h...

  9. Buffalo Metropolitan Area, New York Water Resources Management Study, Tonawanda Creek Watershed. Interim Flood Management Study. Appendices.

    Science.gov (United States)

    1980-12-01

    Counties is reflected in Table B27. Mineral resources in the watershed include salt, gypsum, limestone, dolomite , and natural gas. Salt beds of the...limestone and dolomite in the Tonawanda Creek Watershed is concentrated along the Onondaga and Niagara Escarpments in Erie and Niagara Counties. Production...on the east to Erie County on the west, a distance of 165 miles. High-grade gypsum suitable for calcined building products is currently mined in

  10. Imagined Communities, Contested Watersheds: Challenges to Integrated Water Resources Management in Agricultural Areas

    Science.gov (United States)

    Ferreyra, Cecilia; de Loe, Rob C.; Kreutzwiser, Reid D.

    2008-01-01

    Integrated water resources management is one of the major bottom-up alternatives that emerged during the 1980s in North America as part of the trend towards more holistic and participatory styles of environmental governance. It aims to protect surface and groundwater resources by focusing on the integrated and collaborative management of land and…

  11. Land management, erosion problems and soil and water conservation in Fincha'a watershed, western Ethiopia

    NARCIS (Netherlands)

    Bezuayehu, T.; Sterk, G.

    2010-01-01

    The knowledge of soil erosion processes, attitude towards rational use of resources and institutional support affect the capability of farmers to implement soil and water conservation (SWC) measures. This research was conducted to determine soil erosion problems and the factors that affect the

  12. Watershed scale assessment of the impact of forested riparian zones on stream water quality

    Science.gov (United States)

    J. A. Webber; K. W. J. Williard; M. R. Whiles; M. L. Stone; J. J. Zaczek; D. K. Davie

    2003-01-01

    Federal and state land management agencies have been promoting forest and grass riparian zones to combat non-point source nutrient and sediment pollution of our nations' waters. The majority of research examining the effectiveness of riparian buffers at reducing nutrient and sediment inputs to streams has been conducted at the field scale. This study took a...

  13. Water Quality Trends in the Entiat River Watershed: 2007–2010

    Science.gov (United States)

    Richard D. Woodsmith; Pamela K. Wilkins; Andy Bookter

    2013-01-01

    A large, multiagency effort is underway in the interior Columbia River basin (ICRB) to restore salmon, trout, and char listed as threatened or endangered under the 1973 federal Endangered Species Act. Water quantity and quality are widely recognized as important components of habitat for these depleted salmonid populations. There is also broad concern about...

  14. Spatio-temporal variation in stream water chemistry in a tropical urban watershed

    Science.gov (United States)

    A. Ramirez; K.G. Rosas; A.E. Lugo; O.M. Ramos-Gonzalez

    2014-01-01

    Urban activities and related infrastructure alter the natural patterns of stream physical and chemical conditions. According to the Urban Stream Syndrome, streams draining urban landscapes are characterized by high concentrations of nutrients and ions, and might have elevated water temperatures and variable oxygen concentrations. Here, we report temporal and spatial...

  15. Environmental Systems Simulations for Carbon, Energy, Nitrogen, Water, and Watersheds: Design Principles and Pilot Testing

    NARCIS (Netherlands)

    Lant, C.; Pérez Lapena, B.; Xiong, W.; Kraft, S.; Kowalchuk, R.; Blair, M.

    2016-01-01

    Guided by the Next Generation Science Standards and elements of problem-based learning, four human-environment systems simulations are described in brief—carbon, energy, water, and watershed—and a fifth simulation on nitrogen is described in more depth. These science, technology, engineering, and

  16. Advancing water resource management in agricultural, rural, and urbanizing watersheds: Enhancing University involvement

    Science.gov (United States)

    In this research editorial we make four points relative to solving water resource issues: (1) they are complex problems and difficult to solve, (2) some progress has been made on solving these issues, (3) external non-stationary drivers such as land use changes, climate change and variability, and s...

  17. The value of milk in rangelands in Mandera County, Kenya

    Science.gov (United States)

    Ngugi, Keziah; Ertsen, Maurits

    2015-04-01

    Lack of water over expansive regions in Greater Horn of Africa created the rangelands and rangelands created pastoralism. Pastoralism involve keeping of large livestock herds and movement in search of resources, mainly water, pasture, medicine and wild foods. Several studies have been done in the last century and findings pointed at pastoralism being primitive and unsustainable. It has been predicted it would die in the last century but in the rangelands, pastoralism lives on and it is resilient. This study is based in Mandera, a pastoralism county in Kenya that neighbors Ethiopia to the North and Somalia to the East. The study sought to investigate contribution of milk to pastoralism resilience. Interviews were conducted in the field among the pastoralists, women groups, transporters, traders, government officials and consumers of milk. These information was corroborated with actual field investigations in the expansive rangelands of Mandera County. Pastoralists rarely slaughter or sell their livestock even when the animals waste away during droughts. This is because they have been through such cycles before and observed livestock make tremendous recovery when the right conditions were restored. Rangelands lack infrastructure, there are no roads, schools, telephone or hospitals. Pastoralists diet is comprised of rice, wheat and milk. It was established milk was the main source of income among pastoralists in Mandera County. From milk, the pastoralists make income that is used to purchase the other foodstuffs. Milk is available on daily basis in large quantities owing to the large number of livestock. Unfortunately, every pastoralist household produce copious amounts of milk, thus no local demand and transport infrastructure is nonexistent, making sale of milk a near impossible task. The findings showed the pastoralists have established unique routes through which milk reach the markets in urban centers where demand is high. Urbanization sustain pastoralism. These

  18. 18 CFR 801.9 - Watershed management.

    Science.gov (United States)

    2010-04-01

    ... 18 Conservation of Power and Water Resources 2 2010-04-01 2010-04-01 false Watershed management... GENERAL POLICIES § 801.9 Watershed management. (a) The character, extent, and quality of water resources... management including soil and water conservation measures, land restoration and rehabilitation, erosion...

  19. Water quality of the Canchim?s creek watershed in São Carlos, SP, Brazil, occupied by beef and dairy cattle activities

    Directory of Open Access Journals (Sweden)

    Primavesi Odo

    2002-01-01

    Full Text Available The Canchim?s creek watershed in São Carlos, SP, Brazil, was chosen to evaluate water quality affected by dairy and beef cattle production systems based on tropical pasture. The water samples were collected monthly, during three years, at six sampling points: spring in a tropical forest, spring in an intensive dairy production system, two dam springs, and stream water upward and at the delta. Results showed differences (P<0.01 among sampling points for the mean parameters. True color, hardness, turbidity, electric conductivity, alkalinity, pH, chemical oxygen demand and consumed oxygen explained well differences among sampling points. According to current legislation standards, water quality fitted with most of the established parameters for class 2, with exception of phosphate and iron. The high levels of total phosphorus, except in the forest spring, classified this water in an eutrophic class, even where soil and water conservation practices were considered adequate.

  20. Water quality of the Canchim’s creek watershed in São Carlos, SP, Brazil, occupied by beef and dairy cattle activities

    Directory of Open Access Journals (Sweden)

    Odo Primavesi

    2002-06-01

    Full Text Available The Canchim’s creek watershed in São Carlos, SP, Brazil, was chosen to evaluate water quality affected by dairy and beef cattle production systems based on tropical pasture. The water samples were collected monthly, during three years, at six sampling points: spring in a tropical forest, spring in an intensive dairy production system, two dam springs, and stream water upward and at the delta. Results showed differences (P<0.01 among sampling points for the mean parameters. True color, hardness, turbidity, electric conductivity, alkalinity, pH, chemical oxygen demand and consumed oxygen explained well differences among sampling points. According to current legislation standards, water quality fitted with most of the established parameters for class 2, with exception of phosphate and iron. The high levels of total phosphorus, except in the forest spring, classified this water in an eutrophic class, even where soil and water conservation practices were considered adequate.

  1. Reconnaissance of ground-water quality at selected wells in the Beaver Creek watershed, Shelby, Fayette, Tipton, and Haywood counties, West Tennessee, July to August 1992

    Science.gov (United States)

    Fielder, A.M.; Roman-Mas, A. J.; Bennett, M.W.

    1994-01-01

    A reconnaissance of water-quality conditions of the water-table aquifer in the Beaver Creek watershed and other rural areas of Shelby, Fayette, Tipton, and Haywood Counties, Tennessee, was conducted during July and August 1992. The reconnaissance was conducted by the U.S. Geological Survey, in cooperation with the Tennessee Department of Agriculture and the University of Tennessee Agricultural Extension Service. The report presents data of selected water-quality constituents and properties of water samples collected from 398 domestic wells, located primarily in rural areas. Nitrate concentrations exceeded 10 milligrams per liter in