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Sample records for agricultural surface waters

  1. Modeling global distribution of agricultural insecticides in surface waters.

    PubMed

    Ippolito, Alessio; Kattwinkel, Mira; Rasmussen, Jes J; Schäfer, Ralf B; Fornaroli, Riccardo; Liess, Matthias

    2015-03-01

    Agricultural insecticides constitute a major driver of animal biodiversity loss in freshwater ecosystems. However, the global extent of their effects and the spatial extent of exposure remain largely unknown. We applied a spatially explicit model to estimate the potential for agricultural insecticide runoff into streams. Water bodies within 40% of the global land surface were at risk of insecticide runoff. We separated the influence of natural factors and variables under human control determining insecticide runoff. In the northern hemisphere, insecticide runoff presented a latitudinal gradient mainly driven by insecticide application rate; in the southern hemisphere, a combination of daily rainfall intensity, terrain slope, agricultural intensity and insecticide application rate determined the process. The model predicted the upper limit of observed insecticide exposure measured in water bodies (n = 82) in five different countries reasonably well. The study provides a global map of hotspots for insecticide contamination guiding future freshwater management and conservation efforts. PMID:25555206

  2. Agricultural insecticides threaten surface waters at the global scale

    PubMed Central

    Stehle, Sebastian; Schulz, Ralf

    2015-01-01

    Compared with nutrient levels and habitat degradation, the importance of agricultural pesticides in surface water may have been underestimated due to a lack of comprehensive quantitative analysis. Increasing pesticide contamination results in decreasing regional aquatic biodiversity, i.e., macroinvertebrate family richness is reduced by ∼30% at pesticide concentrations equaling the legally accepted regulatory threshold levels (RTLs). This study provides a comprehensive metaanalysis of 838 peer-reviewed studies (>2,500 sites in 73 countries) that evaluates, for the first time to our knowledge on a global scale, the exposure of surface waters to particularly toxic agricultural insecticides. We tested whether measured insecticide concentrations (MICs; i.e., quantified insecticide concentrations) exceed their RTLs and how risks depend on insecticide development over time and stringency of environmental regulation. Our analysis reveals that MICs occur rarely (i.e., an estimated 97.4% of analyses conducted found no MICs) and there is a complete lack of scientific monitoring data for ∼90% of global cropland. Most importantly, of the 11,300 MICs, 52.4% (5,915 cases; 68.5% of the sites) exceeded the RTL for either surface water (RTLSW) or sediments. Thus, the biological integrity of global water resources is at a substantial risk. RTLSW exceedances depend on the catchment size, sampling regime, and sampling date; are significantly higher for newer-generation insecticides (i.e., pyrethroids); and are high even in countries with stringent environmental regulations. These results suggest the need for worldwide improvements to current pesticide regulations and agricultural pesticide application practices and for intensified research efforts on the presence and effects of pesticides under real-world conditions. PMID:25870271

  3. Agricultural insecticides threaten surface waters at the global scale.

    PubMed

    Stehle, Sebastian; Schulz, Ralf

    2015-05-01

    Compared with nutrient levels and habitat degradation, the importance of agricultural pesticides in surface water may have been underestimated due to a lack of comprehensive quantitative analysis. Increasing pesticide contamination results in decreasing regional aquatic biodiversity, i.e., macroinvertebrate family richness is reduced by ∼30% at pesticide concentrations equaling the legally accepted regulatory threshold levels (RTLs). This study provides a comprehensive metaanalysis of 838 peer-reviewed studies (>2,500 sites in 73 countries) that evaluates, for the first time to our knowledge on a global scale, the exposure of surface waters to particularly toxic agricultural insecticides. We tested whether measured insecticide concentrations (MICs; i.e., quantified insecticide concentrations) exceed their RTLs and how risks depend on insecticide development over time and stringency of environmental regulation. Our analysis reveals that MICs occur rarely (i.e., an estimated 97.4% of analyses conducted found no MICs) and there is a complete lack of scientific monitoring data for ∼90% of global cropland. Most importantly, of the 11,300 MICs, 52.4% (5,915 cases; 68.5% of the sites) exceeded the RTL for either surface water (RTLSW) or sediments. Thus, the biological integrity of global water resources is at a substantial risk. RTLSW exceedances depend on the catchment size, sampling regime, and sampling date; are significantly higher for newer-generation insecticides (i.e., pyrethroids); and are high even in countries with stringent environmental regulations. These results suggest the need for worldwide improvements to current pesticide regulations and agricultural pesticide application practices and for intensified research efforts on the presence and effects of pesticides under real-world conditions. PMID:25870271

  4. Movement of agricultural chemicals between surface water and ground water, lower Cedar River basin, Iowa

    USGS Publications Warehouse

    Squillace, Paul J.; Caldwell, J.P.; Schulmeyer, P.M.; Harvey, C.A.

    1996-01-01

    Bank storage is probably an important source of agricultural chemicals discharged from the alluvial aquifer but becomes depleted with time after surface runoff. Herbicides discharged from the alluvial aquifer during periods of extended base flow entered the alluvial aquifer with ground-water recharge at some distance from the river. The movement of nitrate between surface water and ground water is minor, when compared to the herbicides, even though nitrite was detected in the Cedar River during runoff.

  5. Comparison of pesticide residues in surface water and ground water of agriculture intensive areas

    PubMed Central

    2014-01-01

    The organochlorines (OClPs) and organophosphates (OPPs) pesticides in surface and ground water having intensive agriculture activity were investigated to evaluate their potential pollution and risks on human health. As per USEPA 8081 B method, liquid-liquid extraction followed by Gas-Chromatographic technique with electron capture detector and mass selective detector (GC-MS) were used for monitoring of pesticides. Among organochlorines, α,β,γ,δ HCH’s, aldrin, dicofol, DDT and its derivatives, α,β endosulphan’s and endosulphan-sulphate were analysed; dichlorovos, ethion, parathion-methyl, phorate, chlorpyrifos and profenofos were determined among organophosphates. As compared to ground water, higher concentrations of OClPs and OPPs were found in surface water. Throughout the monitoring study, α - HCH (0.39 μg/L in Amravati region),α - endosulphan (0.78 μg/L in Yavatmal region), chlorpyrifos (0.25 μg/L in Bhandara region) and parathion-methyl (0.09 μg/L in Amravati region) are frequently found pesticide in ground water, whereas α,β,γ-HCH (0.39 μg/L in Amravati region), α,β - endosulphan (0.42 μg/L in Amravati region), dichlorovos (0.25 μg/L in Yavatmal region), parathion-methyl (0.42 μg/L in Bhandara region), phorate (0.33 μg/L in Yavatmal region) were found in surface water. Surface water was found to be more contaminated than ground water with more number of and more concentrated pesticides. Among pesticides water samples are found to be more contaminated by organophosphate than organochlorine. Pesticides in the surface water samples from Bhandara and Yavatmal region exceeded the EU (European Union) limit of 1.0 μg/L (sum of pesticide levels in surface water) but were within the WHO guidelines for individual pesticides. PMID:24398360

  6. Impact of agriculture on surface water in Ireland Part I. General

    NASA Astrophysics Data System (ADS)

    Toner, Paul F.

    1986-02-01

    The inland freshwaters of Ireland are generally of good quality, a condition at least partly attributable to the relatively small population and industrial base, which are mainly located in coastal areas. The wastes generated by agricultural activities greatly exceed those resulting from domestic and industrial activities. However, the bulk of these agricultural wastes are attributable to grazing livestock and are not likely to lead to pollution of waters. The disposal of manure slurries from intensive rearing operations and silage making are the main agricultural operations which have been implicated in pollution incidents, e.g., fish kills and lake eutrophication. Contamination of surface waters with nitrate and pesticides is not a significant problem at this stage, which reflects the relatively low usage of artificial fertilizers and biocides in Ireland. It is suggested that, in the long term, the main effect of agriculture on Irish surface waters will be eutrophication.

  7. Phosphorus release from agriculture to surface waters: past, present and future in China.

    PubMed

    Chen, M; Chen, J

    2008-01-01

    So far, there is no clear picture at national level regarding the severity, spatial distribution, trend and driving forces of phosphorus (P) release from agriculture to surface waters in China, which presents a major obstacle for surface water quality management and relevant policy-making. By applying a proposed Activity-Unit-Balance (AUB) methodology, this paper retrospects and prospects phosphorus release from agricultural activities to surface waters from 1978 to 2050 in China. Modelling results reveal that P load from agriculture has increased 3.4 times during 1978-2005 and will increase by 1.8 times during 2005-2050. Although major contribution factors are mineral fertiliser application (MFA) and livestock feeding activities (LFAs), LFAs will be the single largest source of increased total P load in the next decades. Most importantly, agricultural pollution in China is spatially overlapped with industrial and domestic pollution, and regions in the southeast to "Heihe-Tengchong" line have to be confronted with an austere challenge to control and manage industrial and domestic pollution as well as pollution from agriculture at present and in future. PMID:18495999

  8. Impact of agriculture on surface water in Ireland Part II. Prospects for the future

    NASA Astrophysics Data System (ADS)

    Sherwood, Marie

    1986-02-01

    Agricultural activity is estimated to be responsible for only 6% (8 km) of the total length (135 km) of seriously polluted river channel, but for over 30% (294 km) of the slightly or moderately polluted length (963 km) of channel recorded to date in the state. This article examines the present sources and causes of pollution from agricultural wastes, and speculates on the likely direction of future trends. The most common sources of surface water pollution are animal manures, silage effluent, runoff from land following spreading, and fertilizers.

  9. Agricultural chemical interchange between ground water and surface water, Cedar River basin, Iowa and Minnesota; a study description

    USGS Publications Warehouse

    Squillace, P.J.; Liszewski, M.J.; Thurman, E.M.

    1993-01-01

    A review of the data collected in the Cedar River basin, Iowa and Minnesota, indicates that atrazine is consistently detected in the main-stem river at concentrations greater than 0.10 microgram per liter even during periods of extended base flow. The primary source of atrazine in the river during these periods of base flow is not known. This study is designed to determine how atrazine and other agricultural chemicals move between ground water and surface water in an alluvial aquifer adjacent to a river. A site has been selected in an unfarmed area adjacent to the Cedar River near Bertram, Iowa, to determine how the concentrations of agricultural chemicals in the alluvial aquifer change as a result of bank storage of surface water. Research also is planned to determine the contribution of agricultural chemicals discharged by the alluvial aquifer into the river during base flow.

  10. Estimating Agricultural Water Use using the Operational Simplified Surface Energy Balance Evapotranspiration Estimation Method

    NASA Astrophysics Data System (ADS)

    Forbes, B. T.

    2015-12-01

    Due to the predominantly arid climate in Arizona, access to adequate water supply is vital to the economic development and livelihood of the State. Water supply has become increasingly important during periods of prolonged drought, which has strained reservoir water levels in the Desert Southwest over past years. Arizona's water use is dominated by agriculture, consuming about seventy-five percent of the total annual water demand. Tracking current agricultural water use is important for managers and policy makers so that current water demand can be assessed and current information can be used to forecast future demands. However, many croplands in Arizona are irrigated outside of areas where water use reporting is mandatory. To estimate irrigation withdrawals on these lands, we use a combination of field verification, evapotranspiration (ET) estimation, and irrigation system qualification. ET is typically estimated in Arizona using the Modified Blaney-Criddle method which uses meteorological data to estimate annual crop water requirements. The Modified Blaney-Criddle method assumes crops are irrigated to their full potential over the entire growing season, which may or may not be realistic. We now use the Operational Simplified Surface Energy Balance (SSEBop) ET data in a remote-sensing and energy-balance framework to estimate cropland ET. SSEBop data are of sufficient resolution (30m by 30m) for estimation of field-scale cropland water use. We evaluate our SSEBop-based estimates using ground-truth information and irrigation system qualification obtained in the field. Our approach gives the end user an estimate of crop consumptive use as well as inefficiencies in irrigation system performance—both of which are needed by water managers for tracking irrigated water use in Arizona.

  11. Significance of urban and agricultural land use for biocide and pesticide dynamics in surface waters.

    PubMed

    Wittmer, I K; Bader, H-P; Scheidegger, R; Singer, H; Lück, A; Hanke, I; Carlsson, C; Stamm, C

    2010-05-01

    Biocides and pesticides are designed to control the occurrence of unwanted organisms. From their point of application, these substances can be mobilized and transported to surface waters posing a threat to the aquatic environment. Historically, agricultural pesticides have received substantially more attention than biocidal compounds from urban use, despite being used in similar quantities. This study aims at improving our understanding of the influence of mixed urban and agricultural land use on the overall concentration dynamics of biocides and pesticides during rain events throughout the year. A comprehensive field study was conducted in a catchment within the Swiss plateau (25 km(2)). Four surface water sampling sites represented varying combinations of urban and agricultural sources. Additionally, the urban drainage system was studied by sampling the only wastewater treatment plant (WWTP) in the catchment, a combined sewer overflow (CSO), and a storm sewer (SS). High temporal resolution sampling was carried out during rain events from March to November 2007. The results, based on more than 600 samples analyzed for 23 substances, revealed distinct and complex concentration patterns for different compounds and sources. Five types of concentration patterns can be distinguished: a) compounds that showed elevated background concentrations throughout the year (e.g. diazinon >50 ng L(-1)), indicating a constant household source; b) compounds that showed elevated concentrations driven by rain events throughout the year (e.g. diuron 100-300 ng L(-1)), indicating a constant urban outdoor source such as facades; c) compounds with seasonal peak concentrations driven by rain events from urban and agricultural areas (e.g. mecoprop 1600 ng L(-1) and atrazine 2500 ng L(-1) respectively); d) compounds that showed unpredictably sharp peaks (e.g. atrazine 10,000 ng L(-1), diazinon 2500 ng L(-1)), which were most probably due to improper handling or even disposal of products; and

  12. Fate and transport of glyphosate and aminomethylphosphonic acid in surface waters of agricultural basins

    USGS Publications Warehouse

    Coupe, R.H.; Kalkhoff, S.J.; Capel, P.D.; Gregoire, C.

    2012-01-01

    Background: Glyphosate [N-(phosphonomethyl)glycine] is a herbicide used widely throughout the world in the production of many crops and is heavily used on soybeans, corn and cotton. Glyphosate is used in almost all agricultural areas of the United States, and the agricultural use of glyphosate has increased from less than 10 000 Mg in 1992 to more than 80 000 Mg in 2007. The greatest intensity of glyphosate use is in the midwestern United States, where applications are predominantly to genetically modified corn and soybeans. In spite of the increase in usage across the United States, the characterization of the transport of glyphosate and its degradate aminomethylphosphonic acid (AMPA) on a watershed scale is lacking. Results: Glyphosate and AMPA were frequently detected in the surface waters of four agricultural basins. The frequency and magnitude of detections varied across basins, and the load, as a percentage of use, ranged from 0.009 to 0.86% and could be related to three general characteristics: source strength, rainfall runoff and flow route. Conclusions: Glyphosate use in a watershed results in some occurrence in surface water; however, the watersheds most at risk for the offsite transport of glyphosate are those with high application rates, rainfall that results in overland runoff and a flow route that does not include transport through the soil. ?? 2011 Society of Chemical Industry.

  13. The Fate and Transport of Glyphosate and AMPA into Surface Waters of Agricultural Watersheds

    NASA Astrophysics Data System (ADS)

    Coupe, R.; Kalkhoff, S.; Capel, P.; Gregoire, C.

    2010-12-01

    Glyphosate [N-(phosphonomethyl)glycine] is a herbicide used widely throughout the world in the production of many crops, but is particularly heavily used on crops which are genetically modified to be glyphosate tolerant: predominately soybeans, corn, potatoes, and cotton. Glyphosate is used extensively in almost all agricultural areas of the United States, and annual application has increased from less than 10,000 Mg in 1992 to more than 80,000 Mg in 2007. The greatest areal use is in the Midwest where glyphosate is applied on genetically modified corn and soybeans. Although use is increasing, the characterization of glyphosate transport on the watershed scale is lacking. Glyphosate, and its degradate AMPA [aminomethylphosphoric acid], was frequently detected in the surface waters of four agricultural watersheds. The load as a percent of use of glyphosate ranged from 0.009 to 0.86 percent and can be related to three factors: source strength, hydrology, and flowpath. Glyphosate use within a watershed results in some occurrence in surface water at the part per billion level; however 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.

  14. Assessing irrigated agriculture's surface water and groundwater consumption by combining satellite remote sensing and hydrologic modelling.

    PubMed

    Peña-Arancibia, Jorge L; Mainuddin, Mohammed; Kirby, John M; Chiew, Francis H S; McVicar, Tim R; Vaze, Jai

    2016-01-15

    Globally, irrigation accounts for more than two thirds of freshwater demand. Recent regional and global assessments indicate that groundwater extraction (GWE) for irrigation has increased more rapidly than surface water extraction (SWE), potentially resulting in groundwater depletion. Irrigated agriculture in semi-arid and arid regions is usually from a combination of stored surface water and groundwater. This paper assesses the usefulness of remotely-sensed (RS) derived information on both irrigation dynamics and rates of actual evapotranspiration which are both input to a river-reach water balance model in order to quantify irrigation water use and water provenance (either surface water or groundwater). The assessment is implemented for the water-years 2004/05-2010/11 in five reaches of the Murray-Darling Basin (Australia); a heavily regulated basin with large irrigated areas and periodic droughts and floods. Irrigated area and water use are identified each water-year (from July to June) through a Random Forest model which uses RS vegetation phenology and actual evapotranspiration as predicting variables. Both irrigated areas and actual evapotranspiration from irrigated areas were compared against published estimates of irrigated areas and total water extraction (SWE+GWE).The river-reach model determines the irrigated area that can be serviced with stored surface water (SWE), and the remainder area (as determined by the Random Forest Model) is assumed to be supplemented by groundwater (GWE). Model results were evaluated against observed SWE and GWE. The modelled SWE generally captures the observed interannual patterns and to some extent the magnitudes, with Pearson's correlation coefficients >0.8 and normalised root-mean-square-error<30%. In terms of magnitude, the results were as accurate as or better than those of more traditional (i.e., using areas that fluctuate based on water resource availability and prescribed crop factors) irrigation modelling. The RS

  15. Effects of lowering nitrogen and phosphorus surpluses in agriculture on the quality of groundwater and surface water in the Netherlands

    NASA Astrophysics Data System (ADS)

    Oenema, Oene; van Liere, Lowie; Schoumans, Oscar

    2005-03-01

    The ecological status of many surface waters in the Netherlands (NL) is poor, due to relatively high discharges of N and P from agriculture, industry and wastewater treatment plants. Agriculture is suggested to be a major source, as discharges from industry and wastewater treatment plants have sharply decreased from the 1980s onwards. Agricultural land covers more than 60% of the total surface area in NL, and most of this land is managed intensively and is intersected by a dense network of ditches (total length ˜300,000 km), streams and lakes. On average, groundwater levels are shallow to very shallow. It has been suggested that nutrient balances of agricultural land are easy to measure proxies for nutrient discharges from agricultural land, though the relationships between nutrient balances and nutrient discharges into groundwater and surface water are not well-established. Thus, we explored the effects of lowering N and P surpluses in NL agriculture on the quality of groundwater and surface waters. Effects of N surpluses in the range of 40-300 kg ha -1 yr -1, and of P surpluses in the range of 0.4-17.5 kg of P per ha per year were examined using an integrated set of mathematical models and databases. Results indicate that nitrate leaching to groundwater and N and P discharges to surface waters are related to both N and P surpluses, hydrological condition, land use and soil type. On a national scale, decreasing N surplus by 1 kg ha -1, decreased nitrate leaching to groundwater on average by 0.08 kg ha -1 and N leaching to surface waters on average by 0.12 kg ha -1. Decreases of N and P concentrations in surface waters upon lowering surpluses were smaller than the calculated discharges. Decreases in N and P concentrations were much smaller in the coastal zone and Lake IJsselmeer, than in regional waters (ditches and small streams). The small improvement in the quality of surface waters upon lowering surpluses in agriculture is related to the relative importance of

  16. Unraveling brackish groundwater - surface water interaction in an agricultural field using direct measurements at the field scale

    NASA Astrophysics Data System (ADS)

    Delsman, Joost; Waterloo, Maarten; Groen, Michel; Groen, Koos

    2014-05-01

    Understanding the interaction between groundwater and surface water is important for a myriad of reasons, including flow forecasting, nutrient transport, and water allocation for agriculture and other water users. This understanding is especially important in deep polder areas in the Netherlands, where brackish groundwater seepage (upward flowing regional groundwater) results in a significant salt load to surface water, and may damage crops if salts reach the rootzone in dry summers. Research on groundwater - surface water interaction historically focused on relatively pristine headwater catchments, only recently shifting somewhat to agricultural catchments. The latter pose specific research challenges, as agricultural activities and active water management can have a significant influence on hydrology. A brackish seepage flux, with a different density as precipitation, may significantly influence flow paths to surface water. Research on this specific topic is, however, lacking. We therefore investigated the interaction between groundwater and surface water in an agricultural catchment with a significant brackish seepage flux. In addition, we investigated the effects of intake of fresh water during periods of precipitation deficits, a common management strategy in lowland regions. We instrumented an agricultural ditch to enable direct, 15 min interval measurements of water fluxes and salinity to both agricultural drains and the ditch separately. These measurements are supported by piezometer nests, soil moisture sensors, temperature sensors, geophysics and a meteorological tower. Measurements focused on the summer period and were taken during two measurement periods: May 2012 - November 2012, and April 2013 - October 2013. Our measurements allowed for a direct, high-frequency separation of hydrological flow routes on this agricultural field between flow to agricultural drains and the ditch. The salinity of seepage water allowed for a relatively easy separation of

  17. At-grade stabilization structure impact on surface water quality of an agricultural watershed.

    PubMed

    Minks, Kyle R; Ruark, Matthew D; Lowery, Birl; Madison, Fred W; Frame, Dennis; Stuntebeck, Todd D; Komiskey, Matthew J; Kraft, George J

    2015-04-15

    Decades of farming and fertilization of farm land in the unglaciated/Driftless Area (DA) of southwestern Wisconsin have resulted in the build-up of P and to some extent, N, in soils. This build-up, combined with steep topography and upper and lower elevation farming (tiered farming), exacerbates problems associated with runoff and nutrient transport in these landscapes. Use of an at-grade stabilization structure (AGSS) as an additional conservation practice to contour strip cropping and no-tillage, proved to be successful in reducing organic and sediment bound N and P within an agricultural watershed located in the DA. The research site was designed as a paired watershed study, in which monitoring stations were installed on the perennial streams draining both control and treatment watersheds. Linear mixed effects statistics were used to determine significant changes in nutrient concentrations before and after installation of an AGSS. Results indicate a significant reduction in storm event total P (TP) concentrations (P = 0.01) within the agricultural watershed after installation of the AGSS, but not total dissolved P (P = 0.23). This indicates that the reduction in P concentration is that of the particulate form. Storm event organic N concentrations were also significantly reduced (P = 0.03) after the AGSS was installed. We conclude that AGSS was successful in reducing the organic and sediment bound N and P concentrations in runoff waters thus reducing their delivery to nearby surface waters. PMID:25657061

  18. Five year water and nitrogen balance for a constructed surface flow wetland treating agricultural drainage waters.

    PubMed

    Borin, Maurizio; Tocchetto, Davide

    2007-07-15

    The performance of a constructed surface flow wetland in reducing diffuse N pollution coming from croplands is being investigated in an ongoing experiment, begun in 1998 in NE Italy. The 0.32 ha wetland is vegetated with Phragmites australis (Cav.) Trin. and Typha latifolia (L.). It receives drainage water from 6 ha of land managed for an experiment on drainage systems, where maize, sugarbeet, winter wheat and soybean are cultivated. During the period 1998-2002, the wetland received from 4698 to 8412 mm of water per year (on average, about 9 times the environmental rainfall); its water regimen was discontinuous and flooding occurred on a variable number of days per year (from 13 to 126). Nitric nitrogen was the most important form of element load. Its concentration in the inflow water over time was rather discontinuous, with median values ranging from 0.2 (in 2001) to 4.5 (in 2000) mg L(-1). Inflow nitric N concentrations were occasionally in the 5-15 mg L(-1) range. Concentrations reduced passing through the wetland, with a more evident effect in the last year. Over 5 years, the wetland received slightly more than 2000 kg ha(-1) of nitrogen, 87% in nitric form mostly from farmland drainage. The remaining 13% of N was applied as organic slurry directly onto the wetland, with 5 distributions during 1998 to assess wetland performance in treating occasional organic loads. Field drainage loads had a discontinuous time pattern and occurred mostly during autumn-winter, with the exception of the 2001-2002 season which was a very dry. The wetland discharged 206 kg ha(-1) of N, over the 5-year period, with an apparent removal efficiency of about 90%. The disappearance was mostly due to plant uptake (1110 kg ha(-1)) and soil accumulation (570 kg ha(-1)), with the contribution of denitrification being estimated at around 7%. PMID:17270250

  19. Dynamics of Nitrogen loads in surface water of an agricultural watershed by modelling approach, the Save, Southwest France.

    NASA Astrophysics Data System (ADS)

    Ferrant, S.; Oeurng, C.; Sauvage, S.; Durand, P.; Probst, J. L.; Sanchez-Perez, J. M.

    2009-04-01

    Agriculture is known to have a great impact of nutrients enrichment on continental water resources. In south-West of France (Gascogne region), water resource are essentially surface water and shallow aquifer. Nitrogen dynamic in river is complex and highly variable throughout season and year, depending on hydrology, landuse, removal in stream. In this context, agricultural impacts on nitrogen concentration are a matter of concern for agricultural decision-maker. In order to introduce sustainable land use concepts in this hilly, clayey and agricultural shallow soil context, the hydrological simulation model SWAT2005 has been tested as a valuable tool to evaluate the consequences of such land use changes on water and nutrient balance components. This semi-distributed hydrological model coupled with agronomical model EPIC is able to simulate the impact of each agricultural landuse at the outlet of the Save catchment (1100 km2). Hydrological parameters model are calibrated based on 14-year historical record (1994-2008). Nitrogen losses have been measured during 2 years (2006-2008) at the outlet and are used to validate the model calibration. Agricultural data at communal scale coupled with Spot image analyses have been used to evaluate agricultural distribution and pressure in SWAT. The aim of this modelling exercise is to simulate nitrogen cycle in whole agricultural Hydrological Response Units (HRU), depending on plant growth and culture rotation, to simulate accurately nitrate load in river. The ability of SWAT to reproduce nitrogen transfert and transformation at this scale and in this agricultural context will be evaluated by a discussion of importance of each nitrogen cycle process in nitrogen losses. SWAT could be a useful tool to test agricultural scenario to improve the nitrogen management in river.

  20. Surface water and groundwater nitrogen dynamics in a well drained riparian forest within a poorly drainged agricultural landscape

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Riparian ecosystems, through their unique position in the agricultural landscape and ability to influence nutrient cycles, can potentially reduce nutrient loading to surface and ground waters. The primary purpose of this study was to determine the efficacy of a well-drained, mixed-deciduous riparia...

  1. Pesticide levels in surface waters in an agricultural-forestry basin in Southern Chile.

    PubMed

    Palma, Graciela; Sánchez, Alejandra; Olave, Yohana; Encina, Francisco; Palma, Rodrigo; Barra, Ricardo

    2004-11-01

    Residues of five pesticides in surface water were surveyed during 2001 and 2003 in the Traiguen river basin in Southern Chile. Simazine, hexazinone, 2,4-D, picloram herbicides and carbendazim fungicide were selected through a pesticide risk classification index. Six sampling stations along the river were set up based on agricultural and forestry land use. The water sampling was carried out before and after the pesticide application periods and in correspondence to some rain events. Pesticides were analyzed by HPLC with DAD detection in a multiresidue analysis. During 2001, in the first sampling campaign (March), the highest concentrations of pesticides were 3.0 microg l(-1) for simazine and hexazinone and 1.8 microg l(-1) for carbendazim. In the second sampling (September), the highest concentration were 9.7 microg l(-1) for 2,4-D, 0.3 microg l(-1) for picloram and 0.4 microg l(-1) for carbendazim. In the last sampling period (December), samples indicated contamination with carbendazim fungicide at levels of up to 1.2 microg l(-1). In sampling carried out on May 2003, no pesticides were detected. In October 2003, the highest concentrations of pesticides were 4.5 microg l(-1) for carbendazim and 2.9 microg l(-1) for 2,4-D. Data are discussed in function of land use and application periods of the products, showing a clear seasonal pattern pollution in the Traiguen river. Risk assessment for these pesticides was calculated by using a risk quotient (RQ = PNEC/PEC). For picloram the calculated RQ < was 0, which indicates that no adverse effects may occur due to the exposure to this herbicide in the Traiguen river basin. For 2,4-D, simazine, hexazinone, carbendazim RQ > 1, meaning that adverse effects could occur and it is necessary to reduce pesticide exposure in surface waters. It is recommended to continue with a pesticide monitoring program and the implementation of ecotoxicological testing with local and standardized species in order to consider the probability of

  2. A new emission-based approach for regulation of N losses from agricultural areas to surface waters

    NASA Astrophysics Data System (ADS)

    Rosenstand Poulsen, Jane; Kronvang, Brian; Bering Ovesen, Niels; Piil, Kristoffer; Kolind Hvid, Søren

    2015-04-01

    Demands for a reduction and hence regulation of nitrogen (N) emissions to streams, lakes and coastal areas are a central part of many river basin management plans under the EU Water Framework Directive. Therefore, large focus has been placed on exploring different mitigation options that can assist in reducing the N emission from agricultural areas. However, the spatial variability in landscape, geology and hydrology entails significant differences in the vulnerability of catchments to intense agricultural activities. Hence, if rigid regulations of N emissions are applied without considering this variability, it will not necessarily lead to an optimum balance between applied fertilisers, yields and loss of excess N to the surrounding surface waters. Therefore, the overall purpose of this pilot study is to develop a concept for regulation of nutrient emissions to surface waters based on a comprehensive stream monitoring design in order to measure the temporal and spatial transport of N at sub-catchment scale. The purpose of such a monitoring design is twofold: i) quantification of the actual N emissions from a given agricultural sub-catchment or even individual farms; ii) quantification at sub-catchment scale of nitrate retention that may ultimately lead to a more precise regulation of N emissions from agricultural areas to surface waters. In order to investigate down to which scale it is feasible to quantify N emissions to surface waters and to develop the best monitoring concept, three catchments subdivided into several sub-catchments in Denmark will be studied during the period 2014-2017. The catchments represent different landscapes and geological settings as well as three different hydrological regimes. In the three catchments, hydrometric stations have been established at the outlet of the drainage networks where continuous measurements are made of water stage. In addition daily water samples and weekly grab samples of water are taken and weekly discharge

  3. The influence of surface water - groundwater interactions on the shallow groundwater in agricultural areas near Fu River, China

    NASA Astrophysics Data System (ADS)

    Brauns, Bentje; Løgstrup Bjerg, Poul; Jakobsen, Rasmus; Song, Xianfang

    2014-05-01

    The Northern China Plain (NPC) is known as a very productive area in China for the production of maize and winter wheat, which is grown by local farmers rotationally without lag phases throughout the year. The needed application of fertilizers and pesticides can hereby have strong impacts on the quality shallow groundwaters. Because 70-80% percent of the annual rainfall in the NCP is limited to the summer months, irrigation in the spring season is a necessity. As high quality groundwater resources from deeper aquifers are a valuable and rare asset in Northern China, it should preferentially be used as drinking water, and farmers therefore often shift to flood irrigation with surface water from streams. It is due to this reason, that large agricultural areas are located very close alongside these waterways; often without buffer zones. Fu River is one of the major feeding streams for the Baiyangdian Lake region in the north of Hebei Province. It springs in the west of the lake area and - after passing the populated city of Baoding (with a population of about 600 000 in the metropolitan area) - continues on its course through agricultural area before it feeds into the lake system. Industrial and domestic wastewater as well as surface runoff from urban and agricultural areas substantiates for a significant amount of the river's recharge and often causes poor water quality. As the water from the river may infiltrate into the shallow groundwater, this could cause further deterioration of the groundwater quality, additionally to the effects of the agricultural activities. However, fluctuations may be high because of the strong seasonal differences in precipitation and depending on the connectivity and dynamics of the system . In order to assess the water quality situation and the potential link between surface water and shallow groundwater in the region, a small-scale investigation site was set up on a typical wheat-maize field that reaches almost up to the river bank in

  4. Surface soil water content spatial organization within irrigated and non-irrigated agricultural fields

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Understanding soil water content variability is important for monitoring and modeling of land surface processes as well as land and water management practices. With regards to in situ probes, it is sometimes assumed that a single local measurement can represent the larger domain, mostly for practic...

  5. Potential of the Conservation Reserve Program to control agricultural surface water pollution

    NASA Astrophysics Data System (ADS)

    Lant, Christopher L.

    1991-07-01

    The Conservation Reserve Program (CRP), initiated by the Conservation Title of the Food Security Act of 1985, is the primary federal program to control nonpointsource pollution in agricultural watersheds of the United States. However, the program is designed primarily to reduce soil erosion rather than to retire croplands in a manner optimal for controlling runoff of sediment and associated pollutants. This study estimates potential enrollment of streamside and floodplain croplands in this ten-year retirement program in order to gauge the potential of the CRP as a water-quality improvement policy. A contingent choice survey design was employed in Fayette County, Illinois, to demonstrate that there is substantial potential for retirement of streamside and floodplain croplands in the CRP. Enrollments in each program climb from less than 6% to over 83% of eligible croplands as the annual rental rate is increased from 20 to 200/acre. Potential retirement of streamside and floodplain croplands declines, however, if tree planting, drainage removal, or a 20-year contract are required. The potential of a CRP-based water-quality program to improve water quality and aquatic ecosystems in agricultural watersheds is thus substantial but constrained by the economic trade-offs that farmers make between crop production and conservation incentives in determining the use of their riparian lands.

  6. The distribution of Salmonella enterica serovars and subtypes in surface water from five agricultural regions across Canada.

    PubMed

    Jokinen, C C; Koot, J; Cole, L; Desruisseau, A; Edge, T A; Khan, I U H; Koning, W; Lapen, D R; Pintar, K D M; Reid-Smith, R; Thomas, J L; Topp, E; Wang, L Y; Wilkes, G; Ziebell, K; van Bochove, E; Gannon, V P J

    2015-06-01

    Serovar prevalence of the zoonotic pathogen, Salmonella enterica, was compared among 1624 surface water samples collected previously from five different Canadian agricultural watersheds over multiple years. Phagetyping, pulsed field gel electrophoresis (PFGE), and antimicrobial resistance subtyping assays were performed on serovars Enteritidis, Typhimurium, and Heidelberg. Serovars and subtypes from surface water were compared with those from animal feces, human sewage, and serovars reported to cause salmonellosis in Canadians. Sixty-five different serovars were identified in surface water; only 32% of these were isolated from multiple watersheds. Eleven of the 13 serovars most commonly reported to cause salmonellosis in Canadians were identified in surface water; isolates of these serovars constituted >40% of the total isolates. Common phagetypes and PFGE subtypes of serovars associated with illness in humans such as S. Enteritidis and S. Typhimurium were also isolated from surface water and animal feces. Antimicrobial resistance was generally low, but was highest among S. Typhimurium. Monitoring of these rivers helps to identify vulnerable areas of a watershed and, despite a relatively low prevalence of S. enterica overall, serovars observed in surface water are an indication of the levels of specific S. enterica serovars present in humans and animals. PMID:25799976

  7. Fate and transport of glyphosate and aminomethylphosphonic acid in surface waters of agricultural basins

    USGS Publications Warehouse

    Gregoire, Caroline; Capel, Paul D.; Coupe, Richard H.; Kalkhoff, Stephen J.

    2011-01-01

    CONCLUSIONS: Glyphosate use in a watershed results in some occurrence in surface water; however, the watersheds most at risk for the offsite transport of glyphosate are those with high application rates, rainfall that results in overland runoff and a flow route that does not include transport through the soil.

  8. Modeling the Surface Water-Groundwater Interaction in Arid and Semi-Arid Regions Impacted by Agricultural Activities

    NASA Astrophysics Data System (ADS)

    Tian, Y.; Wu, B.; Zheng, Y.

    2013-12-01

    In many semi-arid and arid regions, interaction between surface water and groundwater plays an important role in the eco-hydrological system. The interaction is often complicated by agricultural activities such as surface water diversion, groundwater pumping, and irrigation. In existing surface water-groundwater integrated models, simulation of the interaction is often simplified, which could introduce significant simulation uncertainty under certain circumstance. In this study, GSFLOW, a USGS model coupling PRMS and MODFLOW, was improved to better characterize the surface water-groundwater interaction. The practices of water diversion from rivers, groundwater pumping and irrigation are explicitly simulated. In addition, the original kinematic wave routing method was replaced by a dynamic wave routing method. The improved model was then applied in Zhangye Basin (the midstream part of Heihe River Baisn), China, where the famous 'Silk Road' came through. It is a typical semi-arid region of the western China, with extensive agriculture in its oasis. The model was established and calibrated using the data in 2000-2008. A series of numerical experiments were conducted to evaluate the effect of those improvements. It has been demonstrated that with the improvements, the observed streamflow and groundwater level were better reproduced by the model. The improvements have a significant impact on the simulation of multiple fluxes associated with the interaction, such as groundwater discharge, riverbed seepage, infiltration, etc. Human activities were proved to be key elements of the water cycle in the study area. The study results have important implications to the water resources modeling and management in semi-arid and arid basins.

  9. Concentration patterns of agricultural pesticides and urban biocides in surface waters of a catchment of mixed land use

    NASA Astrophysics Data System (ADS)

    Stamm, C.; Wittmer, I.; Bader, H.-P.; Scheidegger, R.; Alder, A.; Lück, A.; Hanke, I.; Singer, H.

    2009-04-01

    Organic pesticides and biocides that are found in surface waters, can originate from agricultural and urban sources. For a long time, agricultural pesticides have received substantially more attention than biocidal compounds from urban use like material protection or in-can preservatives (cosmetics etc.). Recent studies however revealed that the amounts of urban biocides used may exceed those of agricultural pesticides. This study aims at comparing the input of several important pesticides and biocides into a small Swiss stream with a special focus on loss events triggered by rainfall. A set of 16 substances was selected to represent urban and agricultural sources. The selected substances are either only used as biocides (irgarol, isothiazolinones, IPBC), as pesticides (atrazine, sulcotrione, dichlofluanid, tolylfluanid) or have a mixed use (isoproturon, terbutryn, terbutylazine, mecoprop, diazinon, carbendazim) The study catchment has an area of 25 km2 and is inhabited by about 12'000 people. Four sampling sites were selected in the river system in order to reflect different urban and agricultural sources. Additionally, we sampled a combined sewer overflow, a rain sewer and the outflow of a wastewater treatment plant. At each site discharge was measured continuously from March to November 2007. During 16 rain events samples were taken by automatic devices at a high temporal resolution. The results, based on more than 500 analyzed samples, revealed distinct concentration patterns for different compounds and sources. Agricultural pesticides exhibited a strong seasonality as expected based on the application periods. During the first one or two rain events after application the concentrations reached up to several thousand ng/l during peak flow (atrazine, isoproturon). The temporal patterns of urban biocides were more diverse. Some compounds obviously stem from permanent sources independent of rainfall because they were found mostly in the outlet of the wastewater

  10. Mitigation scenario analysis: modelling the impacts of changes in agricultural management practices on surface water quality at the catchment scale

    NASA Astrophysics Data System (ADS)

    Taylor, Sam; He, Yi; Hiscock, Kevin

    2014-05-01

    Increasing human pressures on the natural environment through the demand for increased agricultural productivity have exacerbated and deteriorated water quality conditions within many environments due to an unbalancing of the nutrient cycle. As a consequence, increased agricultural diffuse water pollution has resulted in elevated concentrations of nutrients within surface water and groundwater bodies. This deterioration in water quality has direct consequences for the health of aquatic ecosystems and biodiversity, human health, and the use of water as a resource for public water supply and recreation. To mitigate these potential impacts and to meet commitments under the EU Drinking Water and Water Framework Directives, there is a need to improve our understanding of the impacts that agricultural land use and management practices have on water quality. Water quality models are one of the tools available which can be used to facilitate this aim. These simplified representations of the physical environment allow a variety of changes to be simulated within a catchment, including for example changes in agricultural land use and management practices, allowing for predictions of the impacts of those measures on water quality to be developed and an assessment to be made of their effectiveness in improving conditions. The aim of this research is to apply the water quality model SWAT (Soil and Water Assessment Tool) to the Wensum catchment (area 650 km2), situated in the East of England, to predict the impacts of potential changes in land use and land management practices on water quality as part of a process to select those measures that in combination will have the greatest potential to improve water quality. Model calibration and validation is conducted at three sites within the catchment against observations of river discharge and nitrate and total phosphorus loads at a monthly time-step using the optimisation algorithm SUFI-2 (Sequential Uncertainty Fitting Version 2

  11. A review of monitoring approaches and outcomes of surface water quality mitigation measures in meso-scale agricultural catchments

    NASA Astrophysics Data System (ADS)

    Melland, Alice; Jordan, Phil; Murphy, Paul; Mellander, Per-Erik; Shortle, Ger

    2013-04-01

    Critical for an informative feedback loop from scientific monitoring of biophysical change, to making and implementing suitable policy to effect the desired change, are both accurate measurement of biophysical change, and measurement or modelling of the causes of change. For example the European Environment Agency uses the DPSIR framework to assess change in the state (S) of natural resources due to changes in specific drivers (D) and pressures (P) that can have an impact (I) and are the focus of policy responses (R). This paper provides a review of meso-catchment scale studies worldwide that have measured the impacts of agricultural land management practice on surface water quality. Approaches for measuring water quality impacts of agricultural mitigation practices in meso-catchments (1-100 km2) ranged from measuring water quality over a time series, such as before and after a land management change, or over a spatial series such as in paired catchments with and without agricultural practice change (or over a gradient of practices or catchment types), and by cause and effect studies that measure sources, pathways and impacts of practices. Agricultural mitigation measures had no measurable effect, or positive, or negative effects on water quality over periods of 3 to 20 years. In most catchments where beneficial effects of mitigation measures were successfully measured, combinations of measures that address nutrient or pollutant sources, pathways, delivery and impact have been implemented. Successful farm measures included substantial reductions in the intensity of the farming systems, improved engineering and crop management to reduce runoff and drainage transport of nutrients and sediment, as well as high rates of implementation of measures across the catchments. In many cases, the potential to measure improvement in one or more water quality indicators was limited by the impact of a few management or weather events. Reasons that water quality did not improve in

  12. Risk assessment of surface water and groundwater pollution through agricultural activity on the catchment area of the Shelek River

    NASA Astrophysics Data System (ADS)

    Zubairov, Bulat; Dautova, Assel

    2015-04-01

    Agricultural activity in rural areas of Kazakhstan can create a potential risk of surface and groundwater pollution. In our contribution, we will focus on the risk assessment of surface water and groundwater pollution in the catchment area of the Shelek River basin in southeast Kazakhstan. Since soviet time, in the research area an intensive cultivation of tobacco was performed which means to use a big amount of pesticides during the growing-process. Therefore, this research was conducted in order to receive reliable data for management decisions justification and for practical testing of approach which is recommended by WHO for drinking water supply based on risks mapping. For our study, the soil and water samples from tobacco fields, artesian spring, and surface water source were taken for analysis on pesticides content. The samples were investigated in laboratory of Centre of Sanitary and Epidemiological Expertise of Almaty city (CSEE) according to approved methods from the national standards which are accepted in Kazakhstan. For the first time, in artesian spring small amount of nitrate pollution was found whose groundwater is one of the drinking water supplies of the region.

  13. Water Depletion Threatens Agriculture

    NASA Astrophysics Data System (ADS)

    Brauman, K. A.; Richter, B. D.; Postel, S.; Floerke, M.; Malsy, M.

    2014-12-01

    Irrigated agriculture is the human activity that has by far the largest impact on water, constituting 85% of global water consumption and 67% of global water withdrawals. Much of this water use occurs in places where water depletion, the ratio of water consumption to water availability, exceeds 75% for at least one month of the year. Although only 17% of global watershed area experiences depletion at this level or more, nearly 30% of total cropland and 60% of irrigated cropland are found in these depleted watersheds. Staple crops are particularly at risk, with 75% of global irrigated wheat production and 65% of irrigated maize production found in watersheds that are at least seasonally depleted. Of importance to textile production, 75% of cotton production occurs in the same watersheds. For crop production in depleted watersheds, we find that one half to two-thirds of production occurs in watersheds that have not just seasonal but annual water shortages, suggesting that re-distributing water supply over the course of the year cannot be an effective solution to shortage. We explore the degree to which irrigated production in depleted watersheds reflects limitations in supply, a byproduct of the need for irrigation in perennially or seasonally dry landscapes, and identify heavy irrigation consumption that leads to watershed depletion in more humid climates. For watersheds that are not depleted, we evaluate the potential impact of an increase in irrigated production. Finally, we evaluate the benefits of irrigated agriculture in depleted and non-depleted watersheds, quantifying the fraction of irrigated production going to food production, animal feed, and biofuels.

  14. Pesticides in surface water from three agricultural basins in south-central Georgia, 1993-97

    USGS Publications Warehouse

    Hatzell, H.H.

    1996-01-01

    Twenty-two of 43 pesticides analyzed were detected in 128 water samples collected from Tucsawhatchee Creek, the Little River, and the Withlacoochee River. These streams drain agricultural basins in south-central Georgia and were sampled from March 1993 through June 1995. Herbicides were detected more frequently than insecticides. The most frequently detected herbicides were atrazineand metolachlor and the most frequently detected insecticide was carbaryl. Pesticide concentrations in the three streams were low and did not exceed U.S. Environmental Protection Agency drinking water standards. The maximum pesticide concentration was 2.6 ug/L (micrograms per liter) for propargite, a miticide detected in only one sample. The maximum concentrations of the remaining 21 pesticides were less than 0.25 ug/L. The median concentrations were equal to the method detection limit for all pesticides except atrazine (0.008 ug/L) and metolachlor (0.012 ug/L). The ratio of herbicidedetections to nondetections was largest in the planting season, smaller in the harvest season and smallest in the fallow season for the three basins.The same pattern existed for the insecticide ratios in the Little River and the Withlacoochee River. Pairwise correlations between concentrations of atrazine and metolachlor and four parameters (discharge, and concentrations of dissolved organiccarbon, suspended organic carbon, and suspended fine sediment) were evaluated for each stream. The strongest correlations existed between metolachlor and mean daily discharge and metolachlor and fine sediment in the Withlacoochee River. The only significant correlation for the Little River was between atrazine and suspended fine sediment.

  15. Effects of surface run-off on the transport of agricultural chemicals to ground water in a sandplain setting

    USGS Publications Warehouse

    Delin, G.N.; Landon, M.K.

    2002-01-01

    An experiment was conducted at a depressional (lowland) and an upland site in sandy soils to evaluate the effects of surface run-off on the transport of agricultural chemicals to ground water. Approximately 16.5 cm of water was applied to both sites during the experiment, representing a natural precipitation event with a recurrence interval of approximately 100 years. Run-off was quantified at the lowland site and was not detected at the upland site during the experiment. Run-off of water to the lowland site was the most important factor affecting differences in the concentrations and fluxes of the agricultural chemicals between the two sites. Run-off of water to the lowland site appears to have played a dual role by diluting chemical concentrations in the unsaturated zone as well as increasing the concentrations at the water table, compared to the upland site. Concentrations of chloride, nitrate and atrazine plus metabolites were noticeably greater at the water table than in the unsaturated zone at both sites. The estimated mass flux of chloride and nitrate to the water table during the test were 5-2 times greater, respectively, at the lowland site compared to the upland site, whereas the flux of sulfate and atrazine plus metabolites was slightly greater at the upland site. Results indicate that matrix flow of water and chemicals was the primary process causing the observed differences between the two sites. Results of the experiment illustrate the effects of heterogeneity and the complexity of evaluating chemical transport through the unsaturated zone. Copyright ?? 2002 Elsevier Science B.V.

  16. Effects of surface run-off on the transport of agricultural chemicals to ground water in a sandplain setting

    USGS Publications Warehouse

    Delin, Geoffrey N.; Landon, Matthew K.

    2002-01-01

    An experiment was conducted at a depressional (lowland) and an upland site in sandy soils to evaluate the effects of surface run-off on the transport of agricultural chemicals to ground water. Approximately 16.5 cm of water was applied to both sites during the experiment, representing a natural precipitation event with a recurrence interval of approximately 100 years. Run-off was quantified at the lowland site and was not detected at the upland site during the experiment. Run-off of water to the lowland site was the most important factor affecting differences in the concentrations and fluxes of the agricultural chemicals between the two sites. Run-off of water to the lowland site appears to have played a dual role by diluting chemical concentrations in the unsaturated zone as well as increasing the concentrations at the water table, compared to the upland site. Concentrations of chloride, nitrate and atrazine plus metabolites were noticeably greater at the water table than in the unsaturated zone at both sites. The estimated mass flux of chloride and nitrate to the water table during the test were 5–2 times greater, respectively, at the lowland site compared to the upland site, whereas the flux of sulfate and atrazine plus metabolites was slightly greater at the upland site. Results indicate that matrix flow of water and chemicals was the primary process causing the observed differences between the two sites. Results of the experiment illustrate the effects of heterogeneity and the complexity of evaluating chemical transport through the unsaturated zone.

  17. Dynamic factor modeling of ground and surface water levels in an agricultural area adjacent to Everglades National Park

    NASA Astrophysics Data System (ADS)

    Ritter, A.; Muñoz-Carpena, R.

    2006-02-01

    The extensive eastern boundary of Everglades National Park (ENP) in south Florida (USA) is subject to one the most expensive and ambitious environmental restoration projects in history. Understanding and predicting the interaction between the shallow aquifer and surface water is a key component for fine-tuning the process. The Frog Pond is an intensively instrumented agricultural 2023 ha area adjacent to ENP. The interactions among 21 multivariate daily time series (ground and surface water elevations, rainfall and evapotranspiration) available from this area were studied by means of dynamic factor analysis, a novel technique in the field of hydrology. This method is designed to determine latent or background effects governing variability or fluctuations in non-stationary time series. Water levels in 16 wells and two drainage ditch locations inside the area were selected as response variables, and canal levels and net recharge as explanatory variables. Elevations in the two canals delimiting the Frog Pond area were found to be the main factors explaining the response variables. This influence of canal elevations on water levels inside the area was complementary and inversely related to the distance between the observation point and each canal. Rainfall events do not affect daily water levels significantly but are responsible for instantaneous or localized groundwater responses that in some cases can be directly associated with the risk of flooding. This close coupling between surface and groundwater levels, that corroborates that found by other authors using different methods, could hinder on-going environmental restoration efforts in the area by bypassing the function of wetlands and other surface features. An empirical model with a reduced set of parameters was successfully developed and validated in the area by interpolating the results from the dynamic factor analysis across the spatial domain (coefficient of efficiency across the domain: 0.66-0.99). Although

  18. ALTERNATIVE URBANIZATION SCENARIOS FOR AN AGRICULTURAL WATERSHED: DESIGN CRITERIA, SOCIAL CONSTRAINTS, AND EFFECTS ON GROUNDWATER AND SURFACE WATER SYSTEMS

    EPA Science Inventory

    Agricultural landscapes are being urbanized throughout the United States, resulting in the degradation of aquatic systems. Fundamental changes in watershed hydrology result from the construction of impervious surfaces (roofs, streets, sidewalks). As impervious surface area ...

  19. Dynamics of suspended sediment in surface water of an agricultural watershed by modelling approach, the Save, Southwest France.

    NASA Astrophysics Data System (ADS)

    Chantha, O.; Ferrant, S.; Baqué, D.; Sauvage, S.; Sánchez-Pérez, J.-M.

    2009-04-01

    The comprehension of surface water contaminant dynamics (pesticides, metals) is of great importance in order to better improve water quality management. In this context, the quantification of Suspended Sediment (SS) dynamics in surface water at the watershed scale is the first study step as SS corresponds to the carrier phase for some contaminants. The objective of this paper is to quantify suspended sediment at watershed scale, and to identify transport process through temporal landscape variations by modelling approach, using the agro-hydrological model SWAT 2005, adapted from small to large watershed. The study site is a dominant agricultural watershed of 1100 km2 (the Save, tributary of the Garonne) located in southwest France. The model is calibrated then validated based on 14-year historical record (1994-2008) for flow parameters and on 4 years (1994-96 and 2007-08) for SS. The river discharge estimated from the model is compared with observed flow using statistical parameters so as to evaluate the performances of the recent hydrologic simulations. A discussion on the results of model calibration, parameterization and optimum model parameters is presented. Then the evaluation of SS by comparing data measurements and data simulated will be discussed in order to improve the dynamic of SS at the watershed scale.

  20. Evaluating the potential of 'on-line' constructed wetlands for mitigating pesticide transfers from agricultural land to surface waters

    NASA Astrophysics Data System (ADS)

    Whelan, Michael; Ramos, Andre; Guymer, Ian; Villa, Raffaella; Jefferson, Bruce

    2016-04-01

    Pesticides make important contributions to modern agriculture but losses from land to water can present problems for environmental management, particularly in catchments where surface waters are abstracted for drinking water. Where artificial field drains represent a dominant pathway for pesticide transfers, buffer zones provide little mitigation potential. Instead, "on-line" constructed wetlands have been proposed as a potential means of reducing pesticide fluxes in drainage ditches and headwater streams. Here, we evaluate the potential of small free-surface wetlands to reduce pesticide concentrations in surface waters using a combination of field monitoring and numerical modelling. Two small constructed wetland systems in a first order catchment in Cambridgeshire, UK, were monitored over the 2014-2015 winter season. Discharge was measured at several flow control structures and samples were collected every eight hours and analysed for metaldehyde, a commonly-used molluscicide. Metaldehyde is moderately mobile and, like many other compounds, it has been regularly detected at high concentrations in surface water samples in a number of drinking water supply catchments in the UK over the past few years. However, it is unusually difficult to remove via conventional drinking water treatment which makes it particularly problematical for water companies. Metaldehyde losses from the upstream catchment were significant with peak concentrations occurring in the first storm events in early autumn, soon after application. Concentrations and loads appeared to be unaffected by transit through the wetland over a range of flow conditions - probably due to short solute residence times (quantified via several tracing experiments employing rhodamine WT - a fluorescent dye). A dynamic model, based on fugacity concepts, was constructed to describe chemical fate in the wetland system. The model was used to evaluate mitigation potential and management options under field conditions and

  1. Applicability of rapid and on-site measured enzyme activity for surface water quality monitoring in an agricultural catchment

    NASA Astrophysics Data System (ADS)

    Stadler, Philipp; Farnleitner, Andreas H.; Sommer, Regina; Kumpan, Monika; Zessner, Matthias

    2014-05-01

    For the near real time and on-site detection of microbiological fecal pollution of water, the measurement of beta-D- Glucuronidase (GLUC) enzymatic activity has been suggested as a surrogate parameter and has been already successfully operated for water quality monitoring of ground water resources (Ryzinska-Paier et al. 2014). Due to possible short measure intervals of three hours, this method has high potential as a water quality monitoring tool. While cultivation based standard determination takes more than one working day (Cabral 2010) the potential advantage of detecting the GLUC activity is the high temporal measuring resolution. Yet, there is still a big gap of knowledge on the fecal indication capacity of GLUC (specificity, sensitivity, persistence, etc.) in relation to potential pollution sources and catchment conditions (Cabral 2010, Ryzinska-Paier et al. 2014). Furthermore surface waters are a big challenge for automated detection devices in a technical point of view due to the high sediment load during event conditions. This presentation shows results gained form two years of monitoring in an experimental catchment (HOAL) dominated by agricultural land use. Two enzymatic measurement devices are operated parallel at the catchment outlet to test the reproducibility and precision of the method. Data from continuous GLUC monitoring under both base flow and event conditions is compared with reference samples analyzed by standardized laboratory methods for fecal pollution detection (e.g. ISO 16649-1, Colilert18). It is shown that rapid enzymatic on-site GLUC determination can successfully be operated from a technical point of view for surface water quality monitoring under the observed catchment conditions. The comparison of enzyme activity with microbiological standard analytics reveals distinct differences in the dynamic of the signals during event conditions. Cabral J. P. S. (2010) "Water Microbiology. Bacterial Pathogens and Water" International Journal of

  2. Evaluation of root water uptake in the ISBA-A-gs land surface model using agricultural yield statistics over France

    NASA Astrophysics Data System (ADS)

    Canal, N.; Calvet, J.-C.; Decharme, B.; Carrer, D.; Lafont, S.; Pigeon, G.

    2014-12-01

    The simulation of root water uptake in land surface models is affected by large uncertainties. The difficulty in mapping soil depth and in describing the capacity of plants to develop a rooting system is a major obstacle to the simulation of the terrestrial water cycle and to the representation of the impacts of drought. In this study, long time series of agricultural statistics are used to evaluate and constrain root water uptake models. The inter-annual variability of cereal grain yield and permanent grassland dry matter yield is simulated over France by the Interactions between Soil, Biosphere and Atmosphere, CO2-reactive (ISBA-A-gs) generic land surface model (LSM). The two soil profile schemes available in the model are used to simulate the above-ground biomass (Bag) of cereals and grasslands: a two-layer force-restore (FR-2L) bulk reservoir model and a multi-layer diffusion (DIF) model. The DIF model is implemented with or without deep soil layers below the root zone. The evaluation of the various root water uptake models is achieved by using the French agricultural statistics of Agreste over the 1994-2010 period at 45 cropland and 48 grassland départements, for a range of rooting depths. The number of départements where the simulated annual maximum Bag presents a significant correlation with the yield observations is used as a metric to benchmark the root water uptake models. Significant correlations (p value < 0.01) are found for up to 29 and 77% of the départements for cereals and grasslands, respectively. A rather neutral impact of the most refined versions of the model is found with respect to the simplified soil hydrology scheme. This shows that efforts should be made in future studies to reduce other sources of uncertainty, e.g. by using a more detailed soil and root density profile description together with satellite vegetation products. It is found that modelling additional subroot-zone base flow soil layers does not improve (and may even degrade

  3. Evaluation of root water uptake in the ISBA-A-gs land surface model using agricultural yield statistics over France

    NASA Astrophysics Data System (ADS)

    Canal, N.; Calvet, J.-C.; Decharme, B.; Carrer, D.; Lafont, S.; Pigeon, G.

    2014-05-01

    The interannual variability of cereal grain yield and permanent grassland dry matter yield is simulated over French sites by the Interactions between Soil, Biosphere and Atmosphere, CO2-reactive (ISBA-A-gs) generic Land Surface Model (LSM). The two soil profile schemes available in the model are used to simulate the above-ground biomass (Bag) of cereals and grasslands: a 2-layer force-restore (FR-2L) bulk reservoir model and a multi-layer diffusion (DIF) model. The DIF model is implemented with or without deep soil layers below the root-zone. The evaluation of the various root water uptake models is achieved by using the French agricultural statistics of Agreste over the 1994-2010 period at 45 cropland and 48 grassland sites, for a range of rooting depths. The number of sites where the simulated annual maximum Bag presents a significant correlation with the yield observations is used as a metric to benchmark the root water uptake models. Significant correlations (p value < 0.01) are found for up to 29% of the cereal sites and 77% of the grassland sites. It is found that modelling additional subroot zone base flow soil layers does not improve (and may even degrade) the representation of the interannual variability of the vegetation above-ground biomass. These results are particularly robust for grasslands as calibrated simulations are able to represent the extreme 2003 and 2007 years corresponding to unfavourable and favourable fodder production, respectively.

  4. A Statistical Assessment of the Impact of Agricultural Land Use Intensity on Regional Surface Water Quality at Multiple Scales

    PubMed Central

    Zhang, Weiwei; Li, Hong; Sun, Danfeng; Zhou, Liandi

    2012-01-01

    Understanding the effects of intensive agricultural land use activities on water resources is essential for natural resource management and environmental improvement. In this paper, multi-scale nested watersheds were delineated and the relationships between two representative water quality indexes and agricultural land use intensity were assessed and quantified for the year 2000 using multi-scale regression analysis. The results show that the log-transformed nitrate-nitrogen (NO3-N) index exhibited a relationship with chemical fertilizer input intensity and several natural factors, including soil loss, rainfall and sunlight at the first order watershed scale, while permanganate index (CODMn) had a positive relationship with another two input intensities of pesticides and agricultural plastic mulch and organic manure at the fifth order watershed scale. The first order watershed and the fifth order watershed were considered as the watershed adaptive response units for NO3-N and CODMn, respectively. The adjustment of agricultural input and its intensity may be carried out inside the individual watershed adaptive response unit. The multiple linear regression model demonstrated the cause-and-effect relationship between agricultural land use intensity and stream water quality at multiple scales, which is an important factor for the maintenance of stream water quality. PMID:23202839

  5. A statistical assessment of the impact of agricultural land use intensity on regional surface water quality at multiple scales.

    PubMed

    Zhang, Weiwei; Li, Hong; Sun, Danfeng; Zhou, Liandi

    2012-11-01

    Understanding the effects of intensive agricultural land use activities on water resources is essential for natural resource management and environmental improvement. In this paper, multi-scale nested watersheds were delineated and the relationships between two representative water quality indexes and agricultural land use intensity were assessed and quantified for the year 2000 using multi-scale regression analysis. The results show that the log-transformed nitrate-nitrogen (NO(3)-N) index exhibited a relationship with chemical fertilizer input intensity and several natural factors, including soil loss, rainfall and sunlight at the first order watershed scale, while permanganate index (COD(Mn)) had a positive relationship with another two input intensities of pesticides and agricultural plastic mulch and organic manure at the fifth order watershed scale. The first order watershed and the fifth order watershed were considered as the watershed adaptive response units for NO(3)-N and COD(Mn), respectively. The adjustment of agricultural input and its intensity may be carried out inside the individual watershed adaptive response unit. The multiple linear regression model demonstrated the cause-and-effect relationship between agricultural land use intensity and stream water quality at multiple scales, which is an important factor for the maintenance of stream water quality. PMID:23202839

  6. Modeling concentration patterns of agricultural and urban micropollutants in surface waters in catchment of mixed land use

    NASA Astrophysics Data System (ADS)

    Stamm, C.; Scheidegger, R.; Bader, H. P.

    2012-04-01

    Organic micropollutants detected in surface waters can originate from agricultural and urban sources. Depending on the use of the compounds, the temporal loss patterns vary substantially. Therefore models that simulate water quality in watersheds of mixed land use have to account for all relevant sources. We present here simulation results of a transport model that describes the dynamic of several biocidal compounds as well as the behaviour of human pharmaceuticals. The model consists of the sub-model Rexpo simulating the transfer of the compounds from the point of application to the stream in semi-lumped manner. The river sub-model, which is programmed in the Aquasim software, describes the fate of the compounds in the stream. Both sub-models are process-based. The Rexpo sub-model was calibrated at the scale of a small catchment of 25 km2, which is inhabited by about 12'000 people. Based on the resulting model parameters the loss dynamics of two herbicides (atrazine, isoproturon) and a compound of mixed urban and agricultural use (diuron) were predicted for two nested catchment of 212 and 1696 km2, respectively. The model output was compared to observed time-series of concentrations and loads obtained for the entire year 2009. Additionally, the fate of two pharmaceuticals with constant input (carbamazepine, diclofenac) was simulated for improving the understanding of possible degradation processes. The simulated loads and concentrations of the biocidal compounds differed by a factor of 2 to 3 from the observations. In general, the seasonal patterns were well captured by the model. However, a detailed analysis of the seasonality revealed substantial input uncertainty for the application of the compounds. The model results also demonstrated that for the dynamics of rain-driven losses of biocidal compounds the semi-lumped approach of the Rexpo sub-model was sufficient. Only for simulating the photolytic degradation of diclofenac in the stream the detailed

  7. Effect of the submergence, the bed form geometry, and the speed of the surface water flow on the mitigation of pesticides in agricultural ditches

    NASA Astrophysics Data System (ADS)

    Boutron, Olivier; Margoum, Christelle; Chovelon, Jean-Marc; Guillemain, CéLine; Gouy, VéRonique

    2011-08-01

    Pesticides, which have been extensively used in agriculture, have become a major environmental issue, especially regarding surface and groundwater contamination. Of particular importance are vegetated farm drainage ditches, which can play an important role in the mitigation of pesticide contamination by adsorption onto ditch bed substrates. This role is, however, poorly understood, especially regarding the influence of hydrodynamic parameters, which make it difficult to promote best management practice of these systems. We have assessed the influence of three of these parameters (speed of the surface water flow, submergence, and geometrical characteristics of the bed forms) on the transfer and adsorption of selected pesticides (isoproturon, diuron, tebuconazole, and azoxystrobin) into the bed substrate by performing experiments with a tilted experimental flume, using hemp fibers as a standard of natural organic substrates that are found at the bottom of agricultural ditches. Results show the transfer of pesticides from surface water flow into bed substrate is favored, both regarding the amounts transferred into the bed substrate and the kinetics of the transfer, when the surface water speed and the submergence increase and when the bed forms are made of rectangular shapes. Extrapolation of flume data over a distance of several hundred meters suggests that an interesting possibility for improving the mitigation of pesticides in ditches would be to increase the submergence and to favor bed forms that tend to enhance perturbations and subsequent infiltration of the surface water flow.

  8. Agricultural pesticide applications and observed concentrations in surface waters from four drainage basins in the Central Columbia Plateau, Washington and Idaho, 1993-94

    USGS Publications Warehouse

    Wagner, R.J.; Ebbert, J.C.; Roberts, L.M.; Ryker, S.J.

    1995-01-01

    As part of the U.S. Geological Survey's National Water-Quality Assessment Program, the use and occurrence of agricultural pesticides were investigated in four drainage basins--two dominated by irrigated agriculture and two by dryland agriculture--in the Central Columbia Plateau of eastern Washington. For this study, 85 pesticides or pesticide metabolites were selected for analysis from a list of nearly 400 compounds commonly used in the United States. Pesticide-use data included estimates of the total quantity of herbicides, insecticides, and fungicides applied to croplands in each of the four drainage basins and reported times of application for selected pesticides. Pesticide-occurrence data included concentrations of pesticides in samples collected at one surface-water site at or near the outflow of each of the four drainage basins, where surface waters were sampled one to five times a month from March 1993 through May 1994. Of the 85 pesticides or pesticide metabolites targeted for analysis, a total of 45 different compounds were detected in samples from the four sites, ranging in concentration from at or near the limit of detection (as low as 0.001 microgram per liter) to a maximum of 8.1 micrograms per liter. None of the concentrations of pesticides exceeded the U.S. Environmental Protection Agency (USEPA) drinking water standards, but concentrations of five pesticides exceeded the USEPA freshwater-chronic criteria for the protection of aquatic life. Forty-one different pesticides or pesticide metabolites were detected in surface waters sampled at the two sites representing irrigated agriculture drainage basins. The herbicides atrazine, DCPA, and EPTC were detected most frequently at the two sampling sites. Not all pesticides that were applied were detected, however. For example, disulfoton, phorate, and methyl parathion accounted for 15 percent of the insecticides applied in the two irrigated drainage basins, yet none of these pesticides were detected in

  9. Residence time, chemical and isotopic analysis of nitrate in the groundwater and surface water of a small agricultural watershed in the Coastal Plain, Bucks Branch, Sussex County, Delaware

    USGS Publications Warehouse

    Clune, John W.; Denver, Judith M.

    2012-01-01

    Nitrate is a common contaminant in groundwater and surface water throughout the Nation, and water-resource managers need more detailed small-scale watershed research to guide conservation efforts aimed at improving water quality. Concentrations of nitrate in Bucks Branch are among the highest in the state of Delaware and a scientific investigation was performed to provide water-quality information to assist with the management of agriculture and water resources. A combination of major-ion chemistry, nitrogen isotopic composition and age-dating techniques was used to estimate the residence time and provide a chemical and isotopic analysis of nitrate in the groundwater in the surficial aquifer of the Bucks Branch watershed in Sussex County, Delaware. The land use was more than 90 percent agricultural and most nitrogen inputs were from manure and fertilizer. The apparent median age of sampled groundwater is 18 years and the estimated residence time of groundwater contributing to the streamflow for the entire Bucks Branch watershed at the outlet is approximately 19 years. Concentrations of nitrate exceeded the U.S. Environmental Protection Agency drinking-water standard of 10 milligrams per liter (as nitrogen) in 60 percent of groundwater samples and 42 percent of surface-water samples. The overall geochemistry in the Bucks Branch watershed indicates that agriculture is the predominant source of nitrate contamination and the observed patterns in major-ion chemistry are similar to those observed in other studies on the Mid-Atlantic Coastal Plain. The pattern of enrichment in nitrogen and oxygen isotopes (δ15N and δ18O) of nitrate in groundwater and surface water indicates there is some loss of nitrate through denitrification, but this process is not sufficient to remove all of the nitrate from groundwater discharging to streams, and concentrations of nitrate in streams remain elevated.

  10. Analysis of the potential impacts on surface water quality resulting from the proposed use of the San Luis Drain to transport agricultural drainage through the northern Grasslands

    SciTech Connect

    Quinn, N.W.T.

    1992-05-01

    An Environmental Assessment and initial Study for the interim use of a portion of the San Luis Drain for conveyance water through the Grassland Water District and adjacent Grassland areas was conducted. The project proposes the use of 18 miles of the San Luis Drain for the conveyance of agricultural drainage water for a period of five years and the elimination of agricultural drainage discharges from 76 miles of existing channels in and adjacent to the Grassland Water District. A report was prepared to (a) quantify the potential project effects on surface water quality within Salt and Mud Sloughs and the San Joaquin River using currently available data, and (b) to improve the understanding of existing water supply and drainage operations within the Grassland area. After submission of the original report it was brought to the attention of one of the coauthors that the database on selenium and boron concentrations in drainage water did not include the water quality data collected by the Regional Water Quality Control Board (CRWQCB). In addition, the US Bureau of Reclamation (USBR) requested further examination of Grasslands hydrology to estimate the quantity of supplemental water that would be needed to restore the San Joaquin River to the same TDS and trace element concentrations prior to implementation of the project. This report addresses these issues.

  11. Urban and agricultural contribution of annual loads of glyphosate and AMPA towards surface waters at the Orge River catchment scale (France)

    NASA Astrophysics Data System (ADS)

    Botta, Fabrizio; Chevreuil, Marc; Blanchoud, Hélène

    2010-05-01

    The general use of pesticides in the Orge Basin, located in the southern part of the Paris suburb (France), is damaging surface water quality. Consequently, an increase in the water supply costs is registered by the water supply agencies that are situated downstream the Orge confluence with the Seine River. In this catchment, high uses of glyphosate are registered for fallow fields (upstream part) and for roadway weed control (downstream part). The proportion of glyphosate coming from these two zones was not well known, along with the double source of its metabolite AMPA originated from the degradation of some detergent phosphonates. The aim of this work was firstly to identify the potential sources of glyphosate and AMPA in urban sectors (such as sewerage system inputs) and in agricultural areas and to quantify the origins of urban pesticides pathways towards surface waters at the basin scale. The new approach of this project was to collect information at three different scales to establish a first step of modeling. At the basin scale, 1 year of surface water monitoring at the outlet of the Orge River was useful to establish the inputs towards the Seine River. At the urban catchment scale, the investigations have permitted to record glyphosate and AMPA loads transferred by storm waters and by wastewaters. Loads were estimated during and out of application calendar, in different hydrological conditions such as rainfall with high intensity or dry conditions. Impact of WWTP on surface water was also demonstrated. The third phase of this work was the interpretation of agricultural inputs from two different agricultural catchments of the Orge River. The results showed the impact of urban uses of glyphosate upon the Orge River contamination with annual loads from 100 times higher from the urban zone than from the agricultural one. Storm sewers were recognized to be the main way for glyphosate transfer towards surface waters. A budget of glyphosate and AMPA inputs and

  12. Indirect nitrous oxide emissions from surface water bodies in a lowland arable catchment: a significant contribution to agricultural greenhouse gas budgets?

    PubMed

    Outram, Faye N; Hiscock, Kevin M

    2012-08-01

    In the UK agriculture is by far the largest source of nitrous oxide (N(2)O) emissions. Direct N(2)O emissions as a result of nitrogen (N) application to soils have been well documented in the UK, whereas indirect emissions produced in surface waters and groundwaters from leached N are much less understood with limited data to support IPCC emission factors. Indirect emissions were studied in surface waters in the Upper Thurne, a lowland drained arable catchment in eastern England. All surface waters were found to have dissolved N(2)O concentrations above that expected if in equilibrium with ambient concentrations, demonstrating all surface waters were acting as a source of N(2)O. The drainage channels represented 86% of the total indirect N(2)O flux, followed by wetland areas, 11%, and the river, 3%. The dense drainage network was found to have the highest dissolved N(2)O concentrations of all the water bodies studied with a combined N(2)O flux of 16 kg N(2)O-N per day in March 2007. Such indirect fluxes are comparable to direct fluxes per hectare and represent a significant proportion of the total N(2)O flux for this catchment. Separate emission factors were established for the three different surface water types within the same catchment, suggesting that the one emission factor used in the Intergovernmental Panel on Climate Change (IPCC) methodology for predicting all indirect N(2)O emissions is inappropriate. PMID:22789002

  13. Surface Water and Groundwater Nitrogen Dynamics in a Well Drained Riparian Forest within a Poorly Drained Agricultural Landscape

    EPA Science Inventory

    The effectiveness of riparian zones in mitigating nutrients in ground and surface water depends on the climate, management and hydrogeomorphology of a site. The purpose of this study was to determine the efficacy of a well-drained, mixed-deciduous riparian forest to buffer a ri...

  14. 75 FR 16719 - Agricultural Water Enhancement Program

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-02

    ... Commodity Credit Corporation Agricultural Water Enhancement Program AGENCY: Commodity Credit Corporation and... Agricultural Water Enhancement Program (AWEP) by amending section 1240I of the Food ] Security Act of 1985. The... technical assistance to agricultural producers to implement agricultural water enhancement activities...

  15. Caffeine and agricultural pesticide concentrations in surface water and groundwater on the north shore of Kauai (Hawaii, USA).

    PubMed

    Knee, Karen L; Gossett, Richard; Boehm, Alexandria B; Paytan, Adina

    2010-08-01

    Caffeine has been associated with wastewater pollution in temperate and subtropical locations, but environmental caffeine concentrations in tropical locations have not been reported. The objectives of this study were to measure caffeine and agricultural pesticide (carbaryl, metalaxyl, and metribuzin) concentrations in environmental waters on the tropical north shore of Kauai (Hawaii, USA) and assess whether patterns in caffeine concentration were consistent with a wastewater caffeine source. Groundwater, river, stream and coastal ocean samples were collected in August 2006 and February 2007. Caffeine was detected in all August 2006 samples and in 33% of February 2007 samples at concentrations up to 88ngL(-1). Metribuzin was detected in five samples collected in February 2007. Carbaryl and metalaxyl were not detected in any sample. Caffeine was not detected in offshore ocean samples or river samples upstream of human development. A positive correlation between caffeine and enterococci suggested a possible wastewater caffeine source. PMID:20557899

  16. Phenotypic and Genotypic Characteristics of Shiga Toxin-Producing Escherichia coli Isolated from Surface Waters and Sediments in a Canadian Urban-Agricultural Landscape

    PubMed Central

    Nadya, Stephanie; Delaquis, Pascal; Chen, Jessica; Allen, Kevin; Johnson, Roger P.; Ziebell, Kim; Laing, Chad; Gannon, Victor; Bach, Susan; Topp, Edward

    2016-01-01

    A hydrophobic grid membrane filtration—Shiga toxin immunoblot method was used to examine the prevalence of Shiga toxin-producing Escherichia coli (STEC) in four watersheds located in the Lower Mainland of British Columbia, Canada, a region characterized by rapid urbanization and intensive agricultural activity. STEC were recovered from 21.6, 23.2, 19.5, and 9.2% of surface water samples collected monthly from five sites in each watershed over a period of 1 year. Overall prevalence was subject to seasonal variation however, ranging between 13.3% during fall months and 34.3% during winter months. STEC were also recovered from 23.8% of sediment samples collected in one randomly selected site. One hundred distinct STEC isolates distributed among 29 definitive and 4 ambiguous or indeterminate serotypes were recovered from water and sediments, including isolates from Canadian “priority” serogroups O157 (3), O26 (4), O103 (5), and O111 (7). Forty seven isolates were further characterized by analysis of whole genome sequences to detect Shiga toxin gene (stx 1 and stx 2), intimin gene (eaeA) allelic variants and acquired virulence factors. These analyses collectively showed that surface waters from the region support highly diverse STEC populations that include strains with virulence factors commonly associated with human pathotypes. The present work served to characterize the microbiological hazard implied by STEC to support future assessments of risks to public health arising from non-agricultural and agricultural uses of surface water resources in the region. PMID:27092297

  17. Phenotypic and Genotypic Characteristics of Shiga Toxin-Producing Escherichia coli Isolated from Surface Waters and Sediments in a Canadian Urban-Agricultural Landscape.

    PubMed

    Nadya, Stephanie; Delaquis, Pascal; Chen, Jessica; Allen, Kevin; Johnson, Roger P; Ziebell, Kim; Laing, Chad; Gannon, Victor; Bach, Susan; Topp, Edward

    2016-01-01

    A hydrophobic grid membrane filtration-Shiga toxin immunoblot method was used to examine the prevalence of Shiga toxin-producing Escherichia coli (STEC) in four watersheds located in the Lower Mainland of British Columbia, Canada, a region characterized by rapid urbanization and intensive agricultural activity. STEC were recovered from 21.6, 23.2, 19.5, and 9.2% of surface water samples collected monthly from five sites in each watershed over a period of 1 year. Overall prevalence was subject to seasonal variation however, ranging between 13.3% during fall months and 34.3% during winter months. STEC were also recovered from 23.8% of sediment samples collected in one randomly selected site. One hundred distinct STEC isolates distributed among 29 definitive and 4 ambiguous or indeterminate serotypes were recovered from water and sediments, including isolates from Canadian "priority" serogroups O157 (3), O26 (4), O103 (5), and O111 (7). Forty seven isolates were further characterized by analysis of whole genome sequences to detect Shiga toxin gene (stx 1 and stx 2), intimin gene (eaeA) allelic variants and acquired virulence factors. These analyses collectively showed that surface waters from the region support highly diverse STEC populations that include strains with virulence factors commonly associated with human pathotypes. The present work served to characterize the microbiological hazard implied by STEC to support future assessments of risks to public health arising from non-agricultural and agricultural uses of surface water resources in the region. PMID:27092297

  18. Surface water and groundwater nitrogen dynamics in a well drained riparian forest within a poorly drained agricultural landscape.

    PubMed

    Davis, Jennifer H; Griffith, Stephen M; Wigington, Parker J

    2011-01-01

    The effectiveness of riparian zones in mitigating nutrient in ground and surface water depends on the climate, management, and hydrogeomorphology of a site. The purpose of this study was to determine the efficacy of a well drained, mixed-deciduous riparian forest to buffer a river from N originating from a poorly drained grass seed cropping system. The study site was adjacent to the Calapooia River in the Willamette Valley, Oregon. Water was found to move from the rapid drainage of swale surface water. During winter hydrological events, the riparian forest also received river water. Low nitrate (NO3-) concentrations (0.2-0.4 mg NO3- -NL(-1)) in the shallow groundwater of the cropping system were associated with low rates of mineralization and nitrification (33 kg N ha(-1) yr(-1)) and high grass seed crop uptake of N (155 kg N ha(-1) yr(-1)). The riparian forest soil had higher rates of mineralization (117 kg N ha(-1) yr(-1)) that produced quantities of soil N that were within the range of literature values for plant uptake, leading to relatively low concentrations of shallow groundwater NO3 (0.6-1.8 mg NO3- -NL(-1)). The swale that dissected the cropping system and riparian area was found to have the highest rates of denitrification and to contribute dissolved organic C to the river. Given the dynamic nature of the hydrology of the Calapooia River study site, data suggest that the riparian forest plays a role not only in reducing export of NO3- from the cropping system to the river but also in processing nutrients from river water. PMID:21520758

  19. Agricultural chemicals in ground and surface water in a small watershed in Clayton County, Iowa, 1988-91

    USGS Publications Warehouse

    Kalkhoff, S.J.; Schaap, B.D.

    1995-01-01

    Nitrogen was present in all water samples from Deer Creek. Nitrate concentrations ranged from 0.70 to 17 mg/L. Alachlor was detected in 11 percent of the samples, atrazine in 69 percent, cyanazine in 19 percent, and metolachlor in 33 percent. Alachlor concentrations ranged from less than 0.10 to 0.53 ug/L, atrazine ranged from less than 0.10 to 55 ug/L, cyanazine ranged from less than 0.10 to 12 ug/L, and metolachlor ranged from less than 0.10 to 69 ug/L. Herbicide detections occurred most frequently in late spring and early summer during or just following chemical application. Overland flow is an important source of nitrogen and herbicides to Deer Creek. Substantial amounts of agricultural chemicals are transported from the watershed. As much as 4,700 pounds, or 6.7 pounds per acre, of nitrogen were estimated to be transported from the watershed in 1 year. Nitrogen loads transported from the Deer Creek watershed were less during dry years than during years with average or greater than average rainfall.

  20. Factors affecting the fate and transport of glyphosate and AMPA into surface waters of agricultural watersheds in the United States and Europe

    NASA Astrophysics Data System (ADS)

    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.

  1. Managing agricultural drainage ditches for water quality protection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agricultural drainage ditches are essential for the removal of surface and ground water to allow for crop production in poorly drained agricultural landscapes. Ditches also mediate the flow of pollutants from agroecosystems to downstream water bodies. This paper provides an overview of the science, ...

  2. Vineyard weeds control practices impact on surface water transfers: using numerical tracer experiment coupled to a distributed hydrological model to manage agricultural practices spatial arrangements.

    NASA Astrophysics Data System (ADS)

    Colin, F.; Moussa, R.

    2009-04-01

    In rural basins, agricultural landscape management highly influences water and pollutants transfers. Landuse, agricultural practices and their spatial arrangements are at issue. Hydrological model are widely used to explore impacts of anthropogenic influences on experimental catchments. But planning all spatial arrangements leads to a possible cases count which cannot be considered. On the basis of the recent « numerical experiment » approach, we propose a « numerical tracer function » which had to be coupled to a distributed rainfall-runoff model. This function simulate the transfer of a virtual tracer successively spread on each distributed unit inside the catchment. It allows to rank hydrological spatial units according to their hydrological contribution to the surface flows, particularly at the catchment outlet. It was used with the distributed model MHYDAS in an agricultural context. The case study concerns the experimental Roujan vine-growing catchment (1km², south of France) studied since 1992. In this Mediterranean context, we focus on the soil hydraulic conductivity distributed parameter because it highly depends on weed control practices (chemical weeding induces a lot more runoff than mechanical weeding). We checked model sensitivity analysis to soil hydraulic conductivity spatial arrangement on runoff coefficient, peak discharge and catchment lag-time. Results show (i) the use of the tracer function is more efficient than a random approach to improve sensitivity to spatial arrangements from point of view of simulated discharge range, (ii) the first factor explaining hydrological simulations variability was practices area ratio, (iii) variability induced by practices spatial arrangements was significant on runoff coefficient and peak discharge for balanced practices area ratio and on lag-time for low area ratio of chemical weeding practices. From the actual situation on the experimental Roujan catchment (40% of tilled and 60% of non tilled vineyard

  3. ArcNEMO, a spatially distributed nutrient emission model developed in Python to quantify losses of nitrogen and phosphorous from agriculture to surface waters

    NASA Astrophysics Data System (ADS)

    Van Opstal, Mattias; Tits, Mia; Beckers, Veronique; Batelaan, Okke; Van Orshoven, Jos; Elsen, Annemie; Diels, Jan; D'heygere, Tom; Van Hoof, Kor

    2014-05-01

    Pollution of surface water bodies with nitrogen (N) and phosphorous (P) from agricultural sources is a major problem in areas with intensive agriculture in Europe. The Flemish Environment Agency requires information on how spatially explicit policy measures on manure and fertilizer use, and changes in land use and soil management affect the N and P concentration in the surface waters in the region of Flanders, Belgium. To assist in this, a new spatially distributed, mechanistic nutrient emission model was developed in the open-source language Python. The model is called ArcNEMO (Nutrient Emission MOdel). The model is fully integrated in ArcGIS, but could be easily adapted to work with open-source GIS software. In Flanders, detailed information is available each year on the delineation of each agricultural parcel and the crops grown on them. Parcels are linked to farms, and for each farm yearly manure and fertilizer use is available. To take full advantage of this information and to be able to simulate nutrient losses to the high-density surface water network, the model makes use of grid cells of 50 by 50m. A fertilizer allocation model was developed to calculate from the yearly parcel and farm data the fertilizer and manure input per grid cell for further use in the ArcNEMO-model. The model architecture was chosen such that the model can be used to simulate spatially explicit monthly discharge and losses of N and P to the surface water for the whole of Flanders (13,500 km²) over periods of 10-20 years. The extended time period is necessary because residence times in groundwater and the rates of organic matter turnover imply that water quality reacts slowly to changes of land use and fertilization practices. Vertical water flow and nutrient transport in the unsaturated zone are described per grid cell using a cascading bucket-type model with daily time steps. Groundwater flow is described by solving the 2D-groundwater flow equation using an explicit numerical

  4. The role of C:N:P stoichiometry in affecting denitrification in sediments from agricultural surface and tile-water wetlands.

    PubMed

    Grebliunas, Brian D; Perry, William L

    2016-01-01

    Nutrient stoichiometry within a wetland is affected by the surrounding land use, and may play a significant role in the removal of nitrate (NO3-N). Tile-drained, agricultural watersheds experience high seasonal inputs of NO3-N, but low phosphorus (PO4-P) and dissolved organic carbon (DOC) loads relative to surface water dominated systems. This difference may present stoichiometric conditions that limit denitrification within receiving waterways. We investigated how C:N:P ratios affected denitrification rates of sediments from tile-drained mitigation wetlands incubated for: 0, 5, 10, and 20 days. We then tested whether denitrification rates of sediments from surface-water and tile-drained wetlands responded differently to C:N ratios of 2:1 versus 4:1. Ratios of C:N:P (P < 0.05) and incubation length (P < 0.05) had a significant effect on denitrification in tile-drained wetland sediments. Carbon limitation of denitrification became evident at elevated NO3-N concentrations (20 mg L(-1)). Denitrification measured from tile water and surface water wetland sediments increased significantly (P < 0.05) at the 2:1 and 4:1 C:N treatments. The results from both experiments suggest wetland sediments provide a limiting pool of labile DOC to maintain prolonged NO3-N removal. Also, DOC limitation became more evident at elevated NO3-N concentrations (20 mg L(-1)). Irrespective of NO3-N concentrations, P did not limit denitrification rates. In addition to wetting period, residence time, and maintenance of anaerobic conditions, the availability of labile DOC is playing an important limiting role in sediment denitrification within mitigation wetlands. PMID:27064357

  5. Agriculture and Water Quality. Issues in Agricultural Policy. Agriculture Information Bulletin Number 548.

    ERIC Educational Resources Information Center

    Crowder, Bradley M.; And Others

    Agriculture generates byproducts that may contribute to the contamination of the United States' water supply. Any effective regulations to ban or restrict agricultural chemical or land use practices in order to improve water quality will affect the farm economy. Some farmers will benefit; some will not. Most agricultural pollutants reach surface…

  6. Internal Surface Water Flows

    USGS Publications Warehouse

    Murray, Mitchell H.

    1999-01-01

    Introduction The South Florida Ecosystem Restoration Program is an intergovernmental effort to reestablish and maintain the ecosystem of south Florida. One element of the restoration effort is the development of a firm scientific basis for resource decision making.The U.S. Geological Survey (USGS) provides scientitic information as part of the South Florida Ecosystem Restoration Program. The USGS began its own project, called the South Florida Ecosystem Project in fiscal year 1995 for the purpose of gathering hydrologic, cartographic, and geologic data that relate to the mainland of south Florida, Florida Bay, and the Florida Keys and Reef ecosystems. Historical changes in water-management practices to accommodate a large and rapidly growing urban population along the Atlantic coast, as well as intensive agricultural activities, have resulted in a highly managed hydrologic system with canals, levees, and pumping stations. These structures have altered the hydology of the Everglades ecosystem on both coastal and interior lands. Surface-water flows in a direction south of Lake Okeechobee have been regulated by an extensive canal network, begun in the 1940's, to provide for drainage, flood control, saltwater intrusion control, agricultural requirements, and various environmental needs. Much of the development and subsequent monitoring of canal and river discharge south of Lake Okeechobee has traditionally emphasized the eastern coastal areas of Florida. Recently, more emphasis has been placed on providing a more accurate water budget for internal canal flows.

  7. Pesticide mitigation strategies for surface water quality

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pesticide residues are being increasingly detected in surface water in agricultural and urban areas. In some cases water bodies are being listed under the Clean Water Act 303(d) as impaired and Total Maximum Daily Loads are required to address the impairments in agricultural areas. Pesticides in sur...

  8. Agricultural Water Use under Global Change

    NASA Astrophysics Data System (ADS)

    Zhu, T.; Ringler, C.; Rosegrant, M. W.

    2008-12-01

    Irrigation is by far the single largest user of water in the world and is projected to remain so in the foreseeable future. Globally, irrigated agricultural land comprises less than twenty percent of total cropland but produces about forty percent of the world's food. Increasing world population will require more food and this will lead to more irrigation in many areas. As demands increase and water becomes an increasingly scarce resource, agriculture's competition for water with other economic sectors will be intensified. This water picture is expected to become even more complex as climate change will impose substantial impacts on water availability and demand, in particular for agriculture. To better understand future water demand and supply under global change, including changes in demographic, economic and technological dimensions, the water simulation module of IMPACT, a global water and food projection model developed at the International Food Policy Research Institute, is used to analyze future water demand and supply in agricultural and several non-agricultural sectors using downscaled GCM scenarios, based on water availability simulation done with a recently developed semi-distributed global hydrological model. Risk analysis is conducted to identify countries and regions where future water supply reliability for irrigation is low, and food security may be threatened in the presence of climate change. Gridded shadow values of irrigation water are derived for global cropland based on an optimization framework, and they are used to illustrate potential irrigation development by incorporating gridded water availability and existing global map of irrigation areas.

  9. Agricultural Compounds in Water and Birth Defects.

    PubMed

    Brender, Jean D; Weyer, Peter J

    2016-06-01

    Agricultural compounds have been detected in drinking water, some of which are teratogens in animal models. The most commonly detected agricultural compounds in drinking water include nitrate, atrazine, and desethylatrazine. Arsenic can also be an agricultural contaminant, although arsenic often originates from geologic sources. Nitrate has been the most studied agricultural compound in relation to prenatal exposure and birth defects. In several case-control studies published since 2000, women giving birth to babies with neural tube defects, oral clefts, and limb deficiencies were more likely than control mothers to be exposed to higher concentrations of drinking water nitrate during pregnancy. Higher concentrations of atrazine in drinking water have been associated with abdominal defects, gastroschisis, and other defects. Elevated arsenic in drinking water has also been associated with birth defects. Since these compounds often occur as mixtures, it is suggested that future research focus on the impact of mixtures, such as nitrate and atrazine, on birth defects. PMID:27007730

  10. America's water: Agricultural water demands and the response of groundwater

    NASA Astrophysics Data System (ADS)

    Ho, M.; Parthasarathy, V.; Etienne, E.; Russo, T. A.; Devineni, N.; Lall, U.

    2016-07-01

    Agricultural, industrial, and urban water use in the conterminous United States (CONUS) is highly dependent on groundwater that is largely drawn from nonsurficial wells (>30 m). We use a Demand-Sensitive Drought Index to examine the impacts of agricultural water needs, driven by low precipitation, high agricultural water demand, or a combination of both, on the temporal variability of depth to groundwater across the CONUS. We characterize the relationship between changes in groundwater levels, agricultural water deficits relative to precipitation during the growing season, and winter precipitation. We find that declines in groundwater levels in the High Plains aquifer and around the Mississippi River Valley are driven by groundwater withdrawals used to supplement agricultural water demands. Reductions in agricultural water demands for crops do not, however, lead to immediate recovery of groundwater levels due to the demand for groundwater in other sectors in regions such as Utah, Maryland, and Texas.

  11. The role of dynamic surface water-groundwater exchange on streambed denitrification in a first-order, low-relief agricultural watershed

    NASA Astrophysics Data System (ADS)

    Rahimi, Mina; Essaid, Hedeff I.; Wilson, John T.

    2015-12-01

    The role of temporally varying surface water-groundwater (SW-GW) exchange on nitrate removal by streambed denitrification was examined along a reach of Leary Weber Ditch (LWD), Indiana, a small, first-order, low-relief agricultural watershed within the Upper Mississippi River basin, using data collected in 2004 and 2005. Stream stage, GW heads (H), and temperatures (T) were continuously monitored in streambed piezometers and stream bank wells for two transects across LWD accompanied by synoptic measurements of stream stage, H, T, and nitrate (NO3) concentrations along the reach. The H and T data were used to develop and calibrate vertical two-dimensional, models of streambed water flow and heat transport across and along the axis of the stream. Model-estimated SW-GW exchange varied seasonally and in response to high-streamflow events due to dynamic interactions between SW stage and GW H. Comparison of 2004 and 2005 conditions showed that small changes in precipitation amount and intensity, evapotranspiration, and/or nearby GW levels within a low-relief watershed can readily impact SW-GW interactions. The calibrated LWD flow models and observed stream and streambed NO3 concentrations were used to predict temporal variations in streambed NO3 removal in response to dynamic SW-GW exchange. NO3 removal rates underwent slow seasonal changes, but also underwent rapid changes in response to high-flow events. These findings suggest that increased temporal variability of SW-GW exchange in low-order, low-relief watersheds may be a factor contributing their more efficient removal of NO3.

  12. The role of dynamic surface water-groundwater exchange on streambed denitrification in a first-order, low-relief agricultural watershed

    USGS Publications Warehouse

    Rahimi Kazerooni, Mina N.; Essaid, Hedeff I.; Wilson, John T.

    2015-01-01

    The role of temporally varying surface water-groundwater (SW-GW) exchange on nitrate removal by streambed denitrification was examined along a reach of Leary Weber Ditch (LWD), Indiana, a small, first-order, low-relief agricultural watershed within the Upper Mississippi River basin, using data collected in 2004 and 2005. Stream stage, GW heads (H), and temperatures (T) were continuously monitored in streambed piezometers and stream bank wells for two transects across LWD accompanied by synoptic measurements of stream stage, H, T, and nitrate (NO3) concentrations along the reach. The H and T data were used to develop and calibrate vertical two-dimensional, models of streambed water flow and heat transport across and along the axis of the stream. Model-estimated SW-GW exchange varied seasonally and in response to high-streamflow events due to dynamic interactions between SW stage and GW H. Comparison of 2004 and 2005 conditions showed that small changes in precipitation amount and intensity, evapotranspiration, and/or nearby GW levels within a low-relief watershed can readily impact SW-GW interactions. The calibrated LWD flow models and observed stream and streambed NO3 concentrations were used to predict temporal variations in streambed NO3 removal in response to dynamic SW-GW exchange. NO3 removal rates underwent slow seasonal changes, but also underwent rapid changes in response to high-flow events. These findings suggest that increased temporal variability of SW-GW exchange in low-order, low-relief watersheds may be a factor contributing their more efficient removal of NO3.

  13. A GEO Global Agricultural Water Productivity Mapping System

    NASA Astrophysics Data System (ADS)

    Thenkabail, P. S.; Pozzi, W.; Miller, N. L.; Fekete, B.; Sheffield, J.; Dumenil-Gates, L.

    2009-12-01

    Agriculture is the main consumer of freshwater, and improved precision and accuracy of the terrestrial water cycle requires a more reliable way of monitoring agricultural water use and agricultural water productivity. Wisser et al 2008 reported that agricultural water consumption over the satellite-determined crop acreage (from AVHRR, SPOT VGT), particularly for India and China (Thenkabail et al 2006) was 30% higher than the commonly used Food and Agricultural Organization country-reported agricultural crop census data. We propose further quantification and clarification of this error through the following methodology: 1) greater accuracy in measuring actual area and precise spatial distribution of irrigated and rainfed cropland areas, along with identification of crop types and cropping intensities; 2) satellite monitoring of actual evapotranspiration (water use) by croplands; 3) reconciling agricultural plot information and evapotranspiration against calculated stores of water and water budgets, as derived from a Global Hydrologic Model Multi-Model Ensemble; and (d) modeling and pin-pointing areas of low and high water productivity (WP) to optimize agricultural water use and thus save large quanta of water. We propose producing global irrigated and rainfed areas at finer scales using Landsat 30 m imagery in fusion with MODIS 250 m imagery using the spectral matching technique (Thenkabail et al 2009). Crop water use (water transpired by the crop) and crop water productivity maps can be prepared for terrestrial areas, by using the surface energy balance model, in which evapotranspiration fraction is provided from Landsat ETM+ and\\or MODIS thermal data, combined with locally derived meteorological data such as wind speed, humidity, incoming radiation, and other surface values to derive turbulent diffusion and finally computing reference evapotranspiration (e.g., Penman-Montieth approach), so that sensible heat flux may be deducted from net radiation to derive

  14. Balancing Energy-Water-Agriculture Tradeoffs

    NASA Astrophysics Data System (ADS)

    Tidwell, V.; Hightower, M.

    2011-12-01

    In 2005 thermoelectric power production accounted for withdrawals of 201 billion gallons per day (BGD) representing 49% of total withdrawals, making it the largest user of water in the U.S. In terms of freshwater withdrawals thermoelectric power production is the second largest user at 140 BGD just slightly behind freshwater withdrawals for irrigation (USGS 2005). In contrast thermoelectric water consumption is projected at 3.7 BGD or about 3% of total U.S. consumption (NETL 2008). Thermoelectric water consumption is roughly equivalent to that of all other industrial demands and represents one of the fastest growing sectors since 1980. In fact thermoelectric consumption is projected to increase by 42 to 63% between 2005 and 2030 (NETL 2008). Agricultural water consumption has remained relatively constant at roughly 84 BGD or about 84% of total water consumption. While long-term regional electricity transmission planning has traditionally focused on cost, infrastructure utilization, and reliability, issues concerning the availability of water represent an emerging issue. Thermoelectric expansion must be considered in the context of competing demands from other water use sectors balanced with fresh and non-fresh water supplies subject to climate variability. Often such expansion targets water rights transfers from irrigated agriculture. To explore evolving tradeoffs an integrated energy-water-agriculture decision support system has been developed. The tool considers alternative expansion scenarios for the future power plant fleet and the related demand for water. The availability of fresh and non-fresh water supplies, subject to local institutional controls is then explored. This paper addresses integrated energy-water-agriculture planning in the western U.S. and Canada involving an open and participatory process comprising decision-makers, regulators, utility and water managers.

  15. The use of GIS and multi-criteria evaluation (MCE) to identify agricultural land management practices which cause surface water pollution in drinking water supply catchments.

    PubMed

    Grayson, Richard; Kay, Paul; Foulger, Miles

    2008-01-01

    Diffuse pollution poses a threat to water quality and results in the need for treatment for potable water supplies which can prove costly. Within the Yorkshire region, UK, nitrates, pesticides and water colour present particular treatment problems. Catchment management techniques offer an alternative to 'end of pipe' solutions and allow resources to be targeted to the most polluting areas. This project has attempted to identify such areas using GIS based modelling approaches in catchments where water quality data were available. As no model exists to predict water colour a model was created using an MCE method which is capable of predicting colour concentrations at the catchment scale. CatchIS was used to predict pesticide and nitrate N concentrations and was found to be generally capable of reliably predicting nitrate N loads at the catchment scale. The pesticides results did not match the historic data possibly due to problems with the historic pesticide data and temporal and spatially variability in pesticide usage. The use of these models can be extended to predict water quality problems in catchments where water quality data are unavailable and highlight areas of concern. PMID:19029721

  16. Factors Influencing Surface Runoff and Hydrologic Connectivity on an Agricultural Hillslope in Central Pennsylvania

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Improved understanding of surface hydrologic processes is central to the targeted application of agricultural management practices for water quality protection. Factors influencing surface runoff production and hydrologic connectivity were explored at three landscape positions on a single hillslope...

  17. A site-specific agricultural water requirement and footprint estimator (SPARE:WATER 1.0) for irrigation agriculture

    NASA Astrophysics Data System (ADS)

    Multsch, S.; Al-Rumaikhani, Y. A.; Frede, H.-G.; Breuer, L.

    2013-01-01

    The water footprint accounting method addresses the quantification of water consumption in agriculture, whereby three types of water to grow crops are considered, namely green water (consumed rainfall), blue water (irrigation from surface or groundwater) and grey water (water needed to dilute pollutants). Most of current water footprint assessments focus on global to continental scale. We therefore developed the spatial decision support system SPARE:WATER that allows to quantify green, blue and grey water footprints on regional scale. SPARE:WATER is programmed in VB.NET, with geographic information system functionality implemented by the MapWinGIS library. Water requirement and water footprints are assessed on a grid-basis and can then be aggregated for spatial entities such as political boundaries, catchments or irrigation districts. We assume in-efficient irrigation methods rather than optimal conditions to account for irrigation methods with efficiencies other than 100%. Furthermore, grey water can be defined as the water to leach out salt from the rooting zone in order to maintain soil quality, an important management task in irrigation agriculture. Apart from a thorough representation of the modelling concept we provide a proof of concept where we assess the agricultural water footprint of Saudi Arabia. The entire water footprint is 17.0 km3 yr-1 for 2008 with a blue water dominance of 86%. Using SPARE:WATER we are able to delineate regional hot spots as well as crop types with large water footprints, e.g. sesame or dates. Results differ from previous studies of national-scale resolution, underlining the need for regional water footprint assessments.

  18. Virtual water exported from Californian agriculture

    NASA Astrophysics Data System (ADS)

    Nicholas, K. A.; Johansson, E. L.

    2015-12-01

    In an increasingly teleconnected world, international trade drives the exchange of virtual land and water as crops produced in one region are consumed in another. In theory, this can be an optimal use of scarce resources if crops are grown where they can most efficiently be produced. Several recent analyses examine the export of land and water from food production in developing countries where these resources may be more abundant. Here we focus on a developed region and examine the virtual export of land and water from California, the leading agricultural state in the US and the leading global producer of a wide range of fruit, nut, and other specialty crops. As the region faces a serious, ongoing drought, water use is being questioned, and water policy governance re-examined, particularly in the agricultural sector which uses over three-quarters of water appropriations in the state. We look at the blue water embodied in the most widely grown crops in California and use network analysis to examine the trading patterns for flows of virtual land and water. We identify the main crops and export partners representing the majority of water exports. Considered in the context of tradeoffs for land and water resources, we highlight the challenges and opportunities for food production systems to play a sustainable role in meeting human needs while protecting the life-support systems of the planet.

  19. DRINKING WATER FROM AGRICULTURALLY CONTAMINATED GROUNDWATER

    EPA Science Inventory

    Sharp increases in fertilizer and pesticide use throughout the 1960s and 1970s along with generally less attachment to soil particles may result in more widespread contamination of drinking water supplies. he purpose of this study was to highlight the use of agricultural chemical...

  20. Climate policy implications for agricultural water demand

    SciTech Connect

    Chaturvedi, Vaibhav; Hejazi, Mohamad I.; Edmonds, James A.; Clarke, Leon E.; Kyle, G. Page; Davies, Evan; Wise, Marshall A.; Calvin, Katherine V.

    2013-03-01

    Energy, water and land are scarce resources, critical to humans. Developments in each affect the availability and cost of the others, and consequently human prosperity. Measures to limit greenhouse gas concentrations will inevitably exact dramatic changes on energy and land systems and in turn alter the character, magnitude and geographic distribution of human claims on water resources. We employ the Global Change Assessment Model (GCAM), an integrated assessment model to explore the interactions of energy, land and water systems in the context of alternative policies to limit climate change to three alternative levels: 2.5 Wm-2 (445 ppm CO2-e), 3.5 Wm-2 (535 ppm CO2-e) and 4.5 Wm-2 (645 ppm CO2-e). We explore the effects of two alternative land-use emissions mitigation policy options—one which taxes terrestrial carbon emissions equally with fossil fuel and industrial emissions, and an alternative which only taxes fossil fuel and industrial emissions but places no penalty on land-use change emissions. We find that increasing populations and economic growth could be anticipated to almost triple demand for water for agricultural systems across the century even in the absence of climate policy. In general policies to mitigate climate change increase agricultural demands for water still further, though the largest changes occur in the second half of the century, under both policy regimes. The two policies examined profoundly affected both the sources and magnitudes of the increase in irrigation water demands. The largest increases in agricultural irrigation water demand occurred in scenarios where only fossil fuel emissions were priced (but not land-use change emission) and were primarily driven by rapid expansion in bioenergy production. In these scenarios water demands were large relative to present-day total available water, calling into question whether it would be physically possible to produce the associated biomass energy. We explored the potential of improved

  1. Conjunctive use of water resources for sustainable irrigated agriculture

    NASA Astrophysics Data System (ADS)

    Singh, Ajay

    2014-11-01

    The continuous increase in global population and simultaneous decrease in good quality water resources emphasizes the need of using surface water and groundwater resources conjunctively for irrigation. The conjunctive use allows the utilization of poor quality water, which cannot be used as such for the crop production due to its harmful effect on soil and crop health. This paper presents an overview on issues and methods of the conjunctive use of surface water and groundwater resources for sustainable irrigated agriculture. The background of the conjunctive water use and its applications for the management of poor quality water and management of rising watertable are presented. The management of conjunctive water use through the computer-based models is also covered in this review. The advantages and disadvantages of the approach have been described. Conclusions are provided based on this review which could be useful for all the stakeholders.

  2. Surface freezing of water.

    PubMed

    Pérez-Díaz, J L; Álvarez-Valenzuela, M A; Rodríguez-Celis, F

    2016-01-01

    Freezing, melting, evaporation and condensation of water are essential ingredients for climate and eventually life on Earth. In the present work, we show how surface freezing of supercooled water in an open container is conditioned and triggered-exclusively-by humidity in air. Additionally, a change of phase is demonstrated to be triggered on the water surface forming surface ice crystals prior to freezing of bulk. The symmetry of the surface crystal, as well as the freezing point, depend on humidity, presenting at least three different types of surface crystals. Humidity triggers surface freezing as soon as it overpasses a defined value for a given temperature, generating a plurality of nucleation nodes. An evidence of simultaneous nucleation of surface ice crystals is also provided. PMID:27330895

  3. In situ application of stir bar sorptive extraction as a passive sampling technique for the monitoring of agricultural pesticides in surface waters.

    PubMed

    Assoumani, Azziz; Lissalde, Sophie; Margoum, Christelle; Mazzella, Nicolas; Coquery, Marina

    2013-10-01

    Grab sampling and automated sampling are not suitable or logistically too constraining for the monitoring of pesticides in dynamic streams located in agricultural watersheds. In this work, we applied stir bar sorptive extraction (SBSE) Twisters® directly in two small rivers of a French vineyard (herein referred to as "passive SBSE"), for periods of one or two weeks during a month, for the passive sampling of 19 agricultural pesticides. We performed qualitative and semi-quantitative comparisons of the performances of passive SBSE firstly to automated sampling coupled to analytical SBSE, and secondly to the polar organic chemical integrative sampler (POCIS), a well-known passive sampler for hydrophilic micropollutants. Applying passive SBSE in river waters allowed the quantification of more pesticides and in greater amounts than analytical SBSE as shown for samples collected concurrently. Also, passive SBSE and POCIS proved to be complementary techniques in terms of detected molecules; but only passive SBSE was able to integrate a concentration peak triggered by a quick flood event that lasted 5 h. Passive SBSE could be an interesting tool for the monitoring of moderately hydrophobic to hydrophobic organic micropollutants in changing hydrosystems. In this purpose, further studies will focus on the accumulation kinetics of target pesticides and the determination of their sampling rates. PMID:23856404

  4. LOWER PAYETTE RIVER, IDAHO AGRICULTURE IRRIGATION WATER RETURN STUDY AND GROUND WATER EVALUATION, 1992-1993

    EPA Science Inventory

    This report covers the final 17 miles of the Payette River (17050112) and 32,000 acres of irrigated cropland referred to as the Lower Payette State Agricultural Water Quality Project. An in-depth surface and ground water monitoring effort was initiated in June 1992 and completed...

  5. Surface-water surveillance

    SciTech Connect

    Saldi, K.A.; Dirkes, R.L.; Blanton, M.L.

    1995-06-01

    This section of the 1994 Hanford Site Environmental Report summarizes the Surface water on and near the Hanford Site is monitored to determine the potential effects of Hanford operations. Surface water at Hanford includes the Columbia River, riverbank springs, ponds located on the Hanford Site, and offsite water systems directly east and across the Columbia River from the Hanford Site, and offsite water systems directly east and across the Columbia River from the Hanford Site. Columbia River sediments are also included in this discussion. Tables 5.3.1 and 5.3.2 summarize the sampling locations, sample types, sampling frequencies, and sample analyses included in surface-water surveillance activities during 1994. Sample locations are also identified in Figure 5.3.1. This section describes the surveillance effort and summarizes the results for these aquatic environments. Detailed analytical results are reported by Bisping (1995).

  6. Potential depletion of surface water in the Colorado River and agricultural drains by groundwater pumping in the Parker-Palo Verde-Cibola area, Arizona and California

    USGS Publications Warehouse

    Leake, Stanley A.; Owen-Joyce, Sandra J.; Heilman, Julian A.

    2013-01-01

    Water use along the lower Colorado River is allocated as “consumptive use,” which is defined to be the amount of water diverted from the river minus the amount that returns to the river. Diversions of water from the river include surface water in canals and water removed from the river by pumping wells in the aquifer connected to the river. A complication in accounting for water pumped by wells occurs if the pumping depletes water in drains and reduces measured return flow in those drains. In that case, consumptive use of water pumped by the wells is accounted for in the reduction of measured return flow. A method is needed to understand where groundwater pumping will deplete water in the river and where it will deplete water in drains. To provide a basis for future accounting for pumped groundwater in the Parker-Palo Verde-Cibola area, a superposition model was constructed. The model consists of three layers of finite-difference cells that cover most of the aquifer in the study area. The model was run repeatedly with each run having a pumping well in a different model cell. The source of pumped water that is depletion of the river, expressed as a fraction of the pumping rate, was computed for all active cells in model layer 1, and maps were constructed to understand where groundwater pumping depletes the river and where it depletes drains. The model results indicate that if one or more drains exist between a pumping well location and the river, nearly all of the depletion will be from drains, and little or no depletion will come from the Colorado River. Results also show that if a well pumps on a side of the river with no drains in the immediate area, depletion will come from the Colorado River. Finally, if a well pumps between the river and drains that parallel the river, a fraction of the pumping will come from the river and the rest will come from the drains. Model results presented in this report may be considered in development or refinement of strategies

  7. 75 FR 77821 - Agricultural Water Enhancement Program and Cooperative Conservation Partnership Initiative

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-14

    ...; ] DEPARTMENT OF AGRICULTURE Commodity Credit Corporation Agricultural Water Enhancement Program and Cooperative... agreements with the Natural Resources Conservation Service (NRCS) through either the Agricultural Water... Agricultural Water Enhancement Program Legislative Authority The Agricultural Water Enhancement Program...

  8. Agricultural Virtual Water Flows in the USA

    NASA Astrophysics Data System (ADS)

    Konar, M.; Dang, Q.; Lin, X.

    2014-12-01

    Global virtual water trade is an important research topic that has yielded several interesting insights. In this paper, we present a comprehensive assessment of virtual water flows within the USA, a country with global importance as a major agricultural producer and trade power. This is the first study of domestic virtual water flows based upon intra-national food flow data and it provides insight into how the properties of virtual water flows vary across scales. We find that both the value and volume of food flows within the USA are roughly equivalent to half that of international flows. However, USA food flows are more water intensive than international food trade, due to the higher fraction of water-intensive meat trade within the USA. The USA virtual water flow network is more social, homogeneous, and equitable than the global virtual water trade network, although it is still not perfectly equitable. Importantly, a core group of U.S. States is central to the network structure, indicating that both domestic and international trade may be vulnerable to disruptive climate or economic shocks in these U.S. States.

  9. Deficit irrigation for reducing agricultural water use.

    PubMed

    Fereres, Elias; Soriano, María Auxiliadora

    2007-01-01

    At present and more so in the future, irrigated agriculture will take place under water scarcity. Insufficient water supply for irrigation will be the norm rather than the exception, and irrigation management will shift from emphasizing production per unit area towards maximizing the production per unit of water consumed, the water productivity. To cope with scarce supplies, deficit irrigation, defined as the application of water below full crop-water requirements (evapotranspiration), is an important tool to achieve the goal of reducing irrigation water use. While deficit irrigation is widely practised over millions of hectares for a number of reasons - from inadequate network design to excessive irrigation expansion relative to catchment supplies - it has not received sufficient attention in research. Its use in reducing water consumption for biomass production, and for irrigation of annual and perennial crops is reviewed here. There is potential for improving water productivity in many field crops and there is sufficient information for defining the best deficit irrigation strategy for many situations. One conclusion is that the level of irrigation supply under deficit irrigation should be relatively high in most cases, one that permits achieving 60-100% of full evapotranspiration. Several cases on the successful use of regulated deficit irrigation (RDI) in fruit trees and vines are reviewed, showing that RDI not only increases water productivity, but also farmers' profits. Research linking the physiological basis of these responses to the design of RDI strategies is likely to have a significant impact in increasing its adoption in water-limited areas. PMID:17088360

  10. Phosphorus transport by surface and subsurface flow pathways in an upland agricultural watershed

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Improved understanding of phosphorus transport by surface and subsurface flow pathways is critical to protecting water quality in agricultural watersheds. While considerable attention has been devoted to understanding phosphorus losses in overland flow, comparatively limited research has examined ph...

  11. 78 FR 71724 - Recordations, Water Carrier Tariffs, and Agricultural Contract Summaries

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-29

    ... these approvals will expire if not renewed. (1) Recordations, Control Number 2140-0025 (2) Water Carrier Tariffs, Control Number 2140-26 (3) Agricultural Contract Summaries, Control Number 2140-0024 See 78 FR... Surface Transportation Board Recordations, Water Carrier Tariffs, and Agricultural Contract...

  12. Multiscale Land surface feedbacks within agricultural and urban systems

    NASA Astrophysics Data System (ADS)

    Niyogi, D.

    2012-12-01

    This presentation will first discuss the interplay between agricultural landscapes and regional hydroclimatology with particular emphasis on the US Corn Belt. Results and experiences from studies underway as part of a multistate project (Making Climate Information Useful 2 Usable- U2U) will be summarized. The presentation will also highlight experiences regarding the different challenges in developing the regional assessment and guidance regarding sustainable futures. Study results will also be compared with findings from other geographical regions where agriculture - climate linkages are stretching the limits of sustainable water use. A vulnerability framework that can be considered for such agriculture - climate - water links will also be presented. The second issue the presentation will discuss relates to the urban land surface feedbacks and efforts underway to guide efforts related to greening as well as regional landuse planning. The complex links between city structures, urban layouts, and regional climate will be synthesized and the framework regarding a decision support system that is being developed will be presented. Salient points of the modeling efforts, data challenges, and the need for linking multiple disciplines will be presented with special focus on droughts and the need for considering complex multiscale coupled interactions within the analysis.

  13. Estimates of sustainable agricultural water use in northern China based on the equilibrium of groundwater

    NASA Astrophysics Data System (ADS)

    Yali, Y.; Yu, C.

    2015-12-01

    The northern plain is the important food production region in China. However, due to the lack of surface water resources, it needs overmuch exploitation of groundwater to maintain water use in agriculture, which leads to serious environmental problems. Based on the assumption that the reserves of groundwater matches the statistics and keeps on stable, the author explores the reasonable agricultural water and its spatial distribution based on the principle of sustainable utilization of water resources. According to the priorities of water resources allocation (domestic water and ecological water>industrial water>agricultural water), it is proposed to reduce agricultural water use to balance the groundwater reserves on condition that the total water supply is constant. Method: Firstly, we calculate annual average of northern groundwater reserves changes from 2004 to 2010, which is regarded as the reduction of agricultural water; Then, we estimate the food production changes using variables of typical crop water requirements and unit yields assuming that the efficiency of water use keeps the same during the entire study period; Finally, we evaluate the usage of sustainable agricultural water. The results reveal that there is a significant reduction of groundwater reserves in Haihe river basin and Xinjiang oasis regions; And the annual loss of the corn and wheat production is about 1.86 billion kg and 700 million kg respectively due to the reduction of agricultural water; What's more, in order to ensure China's food security and sustainable agricultural water use, in addition to great efforts to develop water-saving agriculture, an important adjustment in the distribution of food production is in need. This study provided a basis to the availability of agricultural water and a new perspective was put forth for an estimation of agricultural water.

  14. Agricultural Adaptation and Water Management in Sri Lanka

    NASA Astrophysics Data System (ADS)

    Stone, E.; Hornberger, G. M.

    2014-12-01

    Efficient management of freshwater resources is critical as concerns with water security increase due to changes in climate, population, and land use. Effective water management in agricultural systems is especially important for irrigation and water quality. This research explores the implications of tradeoffs between maximization of crop yield and minimization of nitrogen loss to the environment, primarily to surface water and groundwater, in rice production in Sri Lanka. We run the DeNitrification-DeComposition (DNDC) model under Sri Lankan climate and soil conditions. The model serves as a tool to simulate crop management scenarios with different irrigation and fertilizer practices in two climate regions of the country. Our investigation uses DNDC to compare rice yields, greenhouse gas (GHG) emissions, and nitrogen leaching under different cultivation scenarios. The results will inform best practices for farmers and decision makers in Sri Lanka on the management of water resources and crops.

  15. The Urban Food-Water Nexus: Modeling Water Footprints of Urban Agriculture using CityCrop

    NASA Astrophysics Data System (ADS)

    Tooke, T. R.; Lathuilliere, M. J.; Coops, N. C.; Johnson, M. S.

    2014-12-01

    Urban agriculture provides a potential contribution towards more sustainable food production and mitigating some of the human impacts that accompany volatility in regional and global food supply. When considering the capacity of urban landscapes to produce food products, the impact of urban water demand required for food production in cities is often neglected. Urban agricultural studies also tend to be undertaken at broad spatial scales, overlooking the heterogeneity of urban form that exerts an extreme influence on the urban energy balance. As a result, urban planning and management practitioners require, but often do not have, spatially explicit and detailed information to support informed urban agricultural policy, especially as it relates to potential conflicts with sustainability goals targeting water-use. In this research we introduce a new model, CityCrop, a hybrid evapotranspiration-plant growth model that incorporates detailed digital representations of the urban surface and biophysical impacts of the built environment and urban trees to account for the daily variations in net surface radiation. The model enables very fine-scale (sub-meter) estimates of water footprints of potential urban agricultural production. Results of the model are demonstrated for an area in the City of Vancouver, Canada and compared to aspatial model estimates, demonstrating the unique considerations and sensitivities for current and future water footprints of urban agriculture and the implications for urban water planning and policy.

  16. Ultrasonic Sensing of Plant Water Needs for Agriculture

    PubMed Central

    Gómez Álvarez-Arenas, Tomas; Gil-Pelegrin, Eustaquio; Ealo Cuello, Joao; Fariñas, Maria Dolores; Sancho-Knapik, Domingo; Collazos Burbano, David Alejandro; Peguero-Pina, Jose Javier

    2016-01-01

    Fresh water is a key natural resource for food production, sanitation and industrial uses and has a high environmental value. The largest water use worldwide (~70%) corresponds to irrigation in agriculture, where use of water is becoming essential to maintain productivity. Efficient irrigation control largely depends on having access to reliable information about the actual plant water needs. Therefore, fast, portable and non-invasive sensing techniques able to measure water requirements directly on the plant are essential to face the huge challenge posed by the extensive water use in agriculture, the increasing water shortage and the impact of climate change. Non-contact resonant ultrasonic spectroscopy (NC-RUS) in the frequency range 0.1–1.2 MHz has revealed as an efficient and powerful non-destructive, non-invasive and in vivo sensing technique for leaves of different plant species. In particular, NC-RUS allows determining surface mass, thickness and elastic modulus of the leaves. Hence, valuable information can be obtained about water content and turgor pressure. This work analyzes and reviews the main requirements for sensors, electronics, signal processing and data analysis in order to develop a fast, portable, robust and non-invasive NC-RUS system to monitor variations in leaves water content or turgor pressure. A sensing prototype is proposed, described and, as application example, used to study two different species: Vitis vinifera and Coffea arabica, whose leaves present thickness resonances in two different frequency bands (400–900 kHz and 200–400 kHz, respectively), These species are representative of two different climates and are related to two high-added value agricultural products where efficient irrigation management can be critical. Moreover, the technique can also be applied to other species and similar results can be obtained. PMID:27428968

  17. Ultrasonic Sensing of Plant Water Needs for Agriculture.

    PubMed

    Gómez Álvarez-Arenas, Tomas; Gil-Pelegrin, Eustaquio; Ealo Cuello, Joao; Fariñas, Maria Dolores; Sancho-Knapik, Domingo; Collazos Burbano, David Alejandro; Peguero-Pina, Jose Javier

    2016-01-01

    Fresh water is a key natural resource for food production, sanitation and industrial uses and has a high environmental value. The largest water use worldwide (~70%) corresponds to irrigation in agriculture, where use of water is becoming essential to maintain productivity. Efficient irrigation control largely depends on having access to reliable information about the actual plant water needs. Therefore, fast, portable and non-invasive sensing techniques able to measure water requirements directly on the plant are essential to face the huge challenge posed by the extensive water use in agriculture, the increasing water shortage and the impact of climate change. Non-contact resonant ultrasonic spectroscopy (NC-RUS) in the frequency range 0.1-1.2 MHz has revealed as an efficient and powerful non-destructive, non-invasive and in vivo sensing technique for leaves of different plant species. In particular, NC-RUS allows determining surface mass, thickness and elastic modulus of the leaves. Hence, valuable information can be obtained about water content and turgor pressure. This work analyzes and reviews the main requirements for sensors, electronics, signal processing and data analysis in order to develop a fast, portable, robust and non-invasive NC-RUS system to monitor variations in leaves water content or turgor pressure. A sensing prototype is proposed, described and, as application example, used to study two different species: Vitis vinifera and Coffea arabica, whose leaves present thickness resonances in two different frequency bands (400-900 kHz and 200-400 kHz, respectively), These species are representative of two different climates and are related to two high-added value agricultural products where efficient irrigation management can be critical. Moreover, the technique can also be applied to other species and similar results can be obtained. PMID:27428968

  18. SURFACE WATER EMAP PROJECT

    EPA Science Inventory

    The surface water component of the EPA Environmental Monitoring and Assessment Program (EMAP) Western Pilot is a five-year effort to assess the ecological condition of rivers and streams across 12 states in the western United States. EMAP is designed to monitor indicators of poll...

  19. Water Quality Response to Changes in Agricultural Land Use Practices at Headwater Streams in Georgia

    EPA Science Inventory

    Poorly managed agricultural watersheds may be one of the most important contributors to high levels of bacterial and sediment loadings in surface waters. We investigated two cattle farms with differing management schemes to compare how physicochemical and meteorological parameter...

  20. Soil Water and Shallow Groundwater Relations in an Agricultural Hillslope

    NASA Astrophysics Data System (ADS)

    Logsdon, S. D.; Schilling, K. E.

    2007-12-01

    Shallow water tables contribute to soil water variations under rolling topography, and soil properties contribute to shallow water table fluctutations. Preferential flow through large soil pores can cause a rise in the water table with little increase in soil water except near the soil surface. Lateral groundwater flow can cause a large rise in water table at toeslope and depressional landscape positions. As plants transpire, water can move up into the root zone from the water table and wet soil below the root zone. Roots can utilize water in the capillary fringe. The purpose of this study was to interface automated measurements of soil water content and water table depth for determining the importance of drainage and upward movement. In 2006 soil water and water table depth were monitored at three positions: shoulder, backslope, and toeslope. Neutron access tubes were manually monitored to 2.3 m depth, and automated soil moisture was measured using CS616 probes installed at 0.3, 0.5, 0.7, and 0.9 m depth. Water table depths were monitored manually and automated, but the automated measurements failed during the season at two sites. In 2007, similar measurements were made at one toeslope position, but the CS616 probes were installed at nine depths and better quality automated well depth equipment was used. The 2006 data revealed little landscape position effect on daytime soil water loss on a wetter date; however, on a dry day just before a rain, daytime water loss was greatest for the toeslope positon and least for the shoulder position. After a period of intense rain, a rapid and significant water table rise occurred at the toeslope position but little water table rise occurred at the other landscape positions. The rapid toeslope water table rise was likely caused by lateral groundwater flow whereas minor water table rise at the other positions was likely due to preferential flow since the soil had not wet up below 0.6 m. Use of automated equipment has improved

  1. Climate change, water rights, and water supply: The case of irrigated agriculture in Idaho

    NASA Astrophysics Data System (ADS)

    Xu, Wenchao; Lowe, Scott E.; Adams, Richard M.

    2014-12-01

    We conduct a hedonic analysis to estimate the response of agricultural land use to water supply information under the Prior Appropriation Doctrine by using Idaho as a case study. Our analysis includes long-term climate (weather) trends and water supply conditions as well as seasonal water supply forecasts. A farm-level panel data set, which accounts for the priority effects of water rights and controls for diversified crop mixes and rotation practices, is used. Our results indicate that farmers respond to the long-term surface and ground water conditions as well as to the seasonal water supply variations. Climate change-induced variations in climate and water supply conditions could lead to substantial damages to irrigated agriculture. We project substantial losses (up to 32%) of the average crop revenue for major agricultural areas under future climate scenarios in Idaho. Finally, farmers demonstrate significantly varied responses given their water rights priorities, which imply that the distributional impact of climate change is sensitive to institutions such as the Prior Appropriation Doctrine.

  2. Grey water on three agricultural catchments in the Czech Republic

    NASA Astrophysics Data System (ADS)

    Blazkova, Sarka D.; Kulasova, Alena

    2014-05-01

    The COST project EU EURO-AGRIWAT focuses apart from other problems on the assessment of water footprint (WF). WF is defined as the quantity of water used to produce some goods or a service. In particular, the WF of an agricultural product is the volume of water used during the crop growing period. It has three components: the green water which is rain or soil moisture transpired by a crop, the blue water which is the amount of irrigation water transpired and the grey water which is the volume of water required to dilute pollutants and to restore the quality standards of the water body. We have been observing three different agricultural catchments. The first of them is Smrzovka Brook, located in the protected nature area in the south part of the Jizerske Mountains. An ecological farming has been carried out there. The second agricultural catchment area is the Kralovsky Creek, which lies in the foothills of the Krkonose Mountains and is a part of an agricultural cooperative. The last agricultural catchment is the Klejnarka stream, located on the outskirts of the fertile Elbe lowlands near Caslav. Catchments Kralovsky Brook and Klejnarka carry out usual agricultural activities. On all three catchments, however, recreational cottages or houses not connected to the sewerage system and/or with inefficient septic tanks occur. The contribution shows our approach to trying to quantify the real grey water from agriculture, i.e. the grey water caused by nutrients not utilised by the crops.

  3. Influence of teleconnection on water quality in agricultural river catchments

    NASA Astrophysics Data System (ADS)

    Mellander, Per-Erik; Jordan, Phil; Shore, Mairead; McDonald, Noeleen; Shortle, Ger

    2015-04-01

    Influences such as weather, flow controls and lag time play an important role in the processes influencing the water quality of agricultural catchments. In particular weather signals need to be clearly considered when interpreting the effectiveness of current measures for reducing nitrogen (N) and phosphorus (P) losses from agricultural sources to water bodies. In north-western Europe weather patterns and trends are influenced by large-scale systems such as the North Atlantic Oscillation (NAO) and the position of the Gulf Stream, the latter expressed as the Gulf Stream North Wall index (GSNW index). Here we present five years of monthly data of nitrate-N concentration in stream water and groundwater (aggregated from sub-hourly monitoring in the stream outlet and monthly sampling in multilevel monitoring wells) from four agricultural catchments (ca. 10 km2) together with monitored weather parameters, long-term weather data and the GSNW index. The catchments are situated in Ireland on the Atlantic seaboard and are susceptible to sudden and seasonal shifts in oceanic climate patterns. Rain anomalies and soil moisture deficit dynamics were similar to the dynamics of the GSNW index. There were monitored changes in nitrate-N concentration in both groundwater and surface water with no apparent connection to agricultural management; instead such changes also appeared to follow the GSNW index. For example, in catchments with poorly drained soils and a 'flashy hydrology' there were seasonal dynamics in nitrate-N concentration that correlated with the seasonal dynamics of the GSNW index. In a groundwater driven catchment there was a consistent increase in nitrate-N concentration over the monitored period which may be the result of increasingly more recharge in summer and autumn (as indicated by more flux in the GSNW index). The results highlight that the position of the Gulf Stream may influence the nitrate-N concentration in groundwater and stream water and there is a risk

  4. Simulation of effects of climate change on surface water balances of agricultural lands. Final technical report, 30 September 1992-29 September 1994

    SciTech Connect

    Heilman, J.L.; McFarland, M.J.

    1994-12-31

    In this project, the authors used the simulation model ENWATBAL and a stochastic weather generator (WXGEN) to evaluate the impact of climatic change on water balances of cotton and sorghum, major crops in Texas that differ in their response to elevated CO2. Specific objectives were: test the accuracy of the ENWATBAL model for the study of climate change; determine the sensitivities of soil water evaporation and transpiration of cotton and sorghum to single and multifactor changes in climate and CO2; and assess effects of gradual climate change on water balances of cotton and sorghum in west Texas.

  5. Phosphorus and water budgets in an agricultural basin.

    PubMed

    Faridmarandi, Sayena; Naja, Ghinwa M

    2014-01-01

    Water and phosphorus (P) budgets of a large agricultural basin located in South Florida (Everglades Agricultural Area, EAA) were computed from 2005 to 2012. The annual surface outflow P loading from the EAA averaged 157.2 mtons originating from Lake Okeechobee (16.4 mtons, 10.4%), farms (131.0 mtons, 83.4%), and surrounding basins (9.8 mtons, 6.2%) after attenuation. Farms, urban areas, and the adjacent C-139 basin contributed 186.1, 15.6, and 3.8 mtons/yr P to the canals, respectively. The average annual soil P retention was estimated at 412.5 mtons. Water and P budgets showed seasonal variations with high correlation between rainfall and P load in drainage and surface outflows. Moreover, results indicated that the canals acted as a P sink storing 64.8 mtons/yr. To assess the P loading impact of farm drainage on the canals and on the outflow, dimensionless impact factors were developed. Sixty-two farms were identified with a high and a medium impact factor I1 level contributing 44.5% of the total drainage P load to the canals, while their collective area represented less than 23% of the EAA area (172 farms). Optimizing the best management practice (BMP) strategies on these farms could minimize the environmental impacts on the downstream sensitive wetlands areas. PMID:24955757

  6. Overcoming agricultural pollution of water: The challenge of integrating agricultural and environmental policies in the European union. World Bank technical paper

    SciTech Connect

    Scheierling, S.M.

    1995-04-01

    In an effort to address the particular policy challenges posed by the agriculture/water quality dilemma, this study, focuses on the experience of the European Community (EC), where high levels of nitrate, phosphate, and pesticides in surface and groundwater are a source of increasing concern. Agricultural and water quality-related environmental policies at EC level, as well as national level, are examined, and new policy approaches that try to integrate agricultural and environmental considerations are discussed. This study thus provides insights into policy options for controlling agricultural water pollution, which might be useful in other parts of the world.

  7. PROTECTING SURFACE WATER QUALITY THROUGH UTILIZATION OF INDUSTRIAL BY-PRODUCTS TO REDUCE NUTRIENT TRANSPORT IN SENSITIVE AGRICULTURE-DOMINATED ECOSYSTEMS

    EPA Science Inventory

    Eutrophication is a problem that plagues the Chesapeake Bay. Rainfall induces surface runoff and erosion of the top layer of the soil that consequently generates a flow of phosphorus into the bay and its tributaries. This excess phosphorus fuels eutrophication and ...

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

    NASA Astrophysics Data System (ADS)

    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

  9. Protecting ground water: pesticides and agricultural practices. Technical report (Final)

    SciTech Connect

    Not Available

    1988-02-01

    The booklet presents the results of a project conducted by EPA's Office of Ground-Water Protection to evaluate the potential impacts of various agronomic, irrigation, and pesticide application practices on ground water. The report provides State and local water quality and agricultural officials with technical information to help in the development of programs to protect ground water from pesticide contamination. The report explains the principles involved in reducing the risk of pesticide contamination and describes what is known about the impact of various agricultural practices on pesticide leaching. It is hoped that the information will be helpful to water-quality officials in developing and implementing ground-water protection programs.

  10. Prevalence, antimicrobial resistance and relation to indicator and pathogenic microorganisms of Salmonella enterica isolated from surface waters within an agricultural landscape.

    PubMed

    Economou, Vangelis; Gousia, Panagiota; Kansouzidou, Athina; Sakkas, Hercules; Karanis, Panagiotis; Papadopoulou, Chrissanthy

    2013-07-01

    During a 12 month period (June 2007-May 2008), the prevalence and susceptibility of Salmonella serovars and their relation to specific pathogenic and indicator bacteria in river and coastal waters was investigated. A total of 240 water samples were collected from selected sites in Acheron and Kalamas Rivers and the Ionian Sea coast in north western Greece. The samples were analyzed for Salmonella spp., Listeria spp., Campylobacter spp., Escherichia coli O157, Staphylococci, Pseudomonas spp., Total Coliforms, Fecal Coliforms, Fecal Streptococci, Total Heterotrophic Flora at 20°C and at 37°C, fungi and protozoa (Cryptosporidium, Giardia). Susceptibility tests to nine antimicrobials (ampicillin, amikacin, amoxicillin/clavulavic acid, cefuroxime, ciprofloxacin, cefoxitin, tetracycline, ticarcillin/clavulanic acid, ampicillin/sulbactam) were performed using the disk diffusion method for Salmonella isolates. We isolated 28 serovars of Salmonella spp. identified as Salmonella enteritidis (23), Salmonella thompson (3) and Salmonella virchow (2). Multi-drug resistant Salmonella serovars were isolated from both river and marine waters, with 34.8% of S. enteritidis and 100% of S. virchow being resistant to more than 3 antibiotics. Also we isolated 42 strains of Listeria spp. identified as L. monocytogenes (20), L. innocua (9), L. seeligeri (2) and L. ivanovii (11). All the Listeria isolates were susceptible to the tested antibiotics. No Campylobacter spp., E. coli O157, Cryptosporidium and Giardia were detected. The overall ranges (and average counts) of the indicator bacteria were: Total Coliforms 0-4×10(4)cfu/100ml (3.7×10(3)cfu/100ml), Fecal Coliforms 0-9×10(3)cfu/100ml (9.2×10(2)cfu/100ml), Fecal Streptococci 0-3.5×10(4)cfu/100ml (1.4×10(3)cfu/100ml), Total Heterotrophic Flora at 20°C 0-6×10(3)cfu/ml (10(3)cfu/ml) and at 37°C 0-5×10(3)cfu/ml (4.9×10(2)cfu/ml). Weak or non significant positive Spearman correlations (p<0.05, rs range: 0.13-0.77) were obtained

  11. A Site-sPecific Agricultural water Requirement and footprint Estimator (SPARE:WATER 1.0)

    NASA Astrophysics Data System (ADS)

    Multsch, S.; Al-Rumaikhani, Y. A.; Frede, H.-G.; Breuer, L.

    2013-07-01

    The agricultural water footprint addresses the quantification of water consumption in agriculture, whereby three types of water to grow crops are considered, namely green water (consumed rainfall), blue water (irrigation from surface or groundwater) and grey water (water needed to dilute pollutants). By considering site-specific properties when calculating the crop water footprint, this methodology can be used to support decision making in the agricultural sector on local to regional scale. We therefore developed the spatial decision support system SPARE:WATER that allows us to quantify green, blue and grey water footprints on regional scale. SPARE:WATER is programmed in VB.NET, with geographic information system functionality implemented by the MapWinGIS library. Water requirements and water footprints are assessed on a grid basis and can then be aggregated for spatial entities such as political boundaries, catchments or irrigation districts. We assume inefficient irrigation methods rather than optimal conditions to account for irrigation methods with efficiencies other than 100%. Furthermore, grey water is defined as the water needed to leach out salt from the rooting zone in order to maintain soil quality, an important management task in irrigation agriculture. Apart from a thorough representation of the modelling concept, we provide a proof of concept where we assess the agricultural water footprint of Saudi Arabia. The entire water footprint is 17.0 km3 yr-1 for 2008, with a blue water dominance of 86%. Using SPARE:WATER we are able to delineate regional hot spots as well as crop types with large water footprints, e.g. sesame or dates. Results differ from previous studies of national-scale resolution, underlining the need for regional estimation of crop water footprints.

  12. Factors affecting leaching in agricultural areas and an assessment of agricultural chemicals in the ground water of Kansas

    USGS Publications Warehouse

    Perry, C.A.; Robbins, F.V.; Barnes, P.L.

    1988-01-01

    As assessment of hydrologic factors and agricultural practices that may affect the leaching of agricultural chemicals to groundwater was conducted to evaluate the extent and severity of chemical contamination of groundwater resources in Kansas. The climate of a particular area determines the length of the growing season and the availability of water, at the surface and in the ground, for the growth of plants. Climate, together with surficial geology, soil, and principal aquifers, determines the types of crops to be planted,types of tillage, conservation and irrigation practices, and affects the quantity and method of application of agricultural chemicals. Examination of groundwater nitrate-nitrogen data collected from 766 wells throughout Kansas during 1976-81 indicated that 13 of 14 geohydrologic regions had wells producing samples that exceeded the 10-mg/L drinking water standard determined by the U.S. Environmental Protection Agency. One or more herbicides were detected in water samples from 11 of 56 wells during 1985-86 located in areas susceptible to agricultural leaching. Atrazine was the most common herbicide that was detected; it was detected in water at 9 of 11 wells. Cyanazine was detected in water at three wells; metolachlor at two wells; and metribuzin, alachlor, simazine, and propazine were detected at one well each. (USGS)

  13. Water chemistry responses to hydraulic manipulation of an agricultural wetland

    NASA Astrophysics Data System (ADS)

    Powers, S.; Stanley, E. H.

    2011-12-01

    Small impoundments are often crucial factors for the movement of sediment, organic matter, water-borne nutrients, and toxic materials through river networks. By recent accounting, at least 2.6 million small artificial water bodies exist in the US alone. A large proportion of those structures occur in regions with high intensity of agriculture, such as in the Midwestern grain belt. While small impoundments are aging structures which appear to serve few purposes, some hold ecological and biogeochemical value as artificial wetlands. We documented instantaneous net fluxes of solute (chloride, sulfate, nitrate, ammonium, and soluble reactive phosphorus) through an artificial flow-through wetland in agricultural southern Wisconsin over 6 years which spanned removal of a small dam. Phased dewatering and dam removal ultimately converted the artificial wetland to a canal-like state (increase in mean water velocity from 0.08 to 0.22 m s-1). Mean net flux for chloride across the system averaged nearly 0 g d-1, indicating conservative transport and successful characterization of hydrology. In contrast, net fluxes for other solute forms were altered following loss of the wetland: a persistent net sulfate sink (5-10% of inputs retained), suggestive of sulfate-reducing bacteria, was reduced; seasonal (summer) net sinks for nitrate and ammonium, suggestive of uptake by algae and denitrifying bacteria, were reduced; temporal variability for the net flux of soluble reactive phosphorus was reduced. Overall, loss of the artificial wetland caused by dam removal shifted seasonal and annual net fluxes of biologically available solute toward export. Nutrient retention by artificial wetlands could be important for elemental budgets in regions which have high nutrient loading to surface and ground water.

  14. Water saving through international trade of agricultural products

    NASA Astrophysics Data System (ADS)

    Chapagain, A. K.; Hoekstra, A. Y.; Savenije, H. H. G.

    2006-06-01

    Many nations save domestic water resources by importing water-intensive products and exporting commodities that are less water intensive. National water saving through the import of a product can imply saving water at a global level if the flow is from sites with high to sites with low water productivity. The paper analyses the consequences of international virtual water flows on the global and national water budgets. The assessment shows that the total amount of water that would have been required in the importing countries if all imported agricultural products would have been produced domestically is 1605 Gm3/yr. These products are however being produced with only 1253 Gm3/yr in the exporting countries, saving global water resources by 352 Gm3/yr. This saving is 28 per cent of the international virtual water flows related to the trade of agricultural products and 6 per cent of the global water use in agriculture. National policy makers are however not interested in global water savings but in the status of national water resources. Egypt imports wheat and in doing so saves 3.6 Gm3/yr of its national water resources. Water use for producing export commodities can be beneficial, as for instance in Cote d'Ivoire, Ghana and Brazil, where the use of green water resources (mainly through rain-fed agriculture) for the production of stimulant crops for export has a positive economic impact on the national economy. However, export of 28 Gm3/yr of national water from Thailand related to rice export is at the cost of additional pressure on its blue water resources. Importing a product which has a relatively high ratio of green to blue virtual water content saves global blue water resources that generally have a higher opportunity cost than green water.

  15. Water saving through international trade of agricultural products

    NASA Astrophysics Data System (ADS)

    Chapagain, A. K.; Hoekstra, A. Y.; Savenije, H. H. G.

    2005-11-01

    Many nations save domestic water resources by importing water-intensive products and exporting commodities that are less water intensive. National water saving through the import of a product can imply saving water at a global level if the flow is from sites with high to sites with low water productivity. The paper analyses the consequences of international virtual water flows on the global and national water budgets. The assessment shows that the total amount of water that would have been required in the importing countries if all imported agricultural products would have been produced domestically is 1605 Gm3/yr. These products are however being produced with only 1253 Gm3/yr in the exporting countries, saving global water resources by 352 Gm3/yr. This saving is 28% of the international virtual water flows related to the trade of agricultural products and 6% of the global water use in agriculture. National policy makers are however not interested in global water savings but in the status of national water resources. Egypt imports wheat and in doing so saves 3.6 Gm3/yr of its national water resources. Water use for producing export commodities can be beneficial, as for instance in Cote d'Ivoire, Ghana and Brazil, where the use of green water resources (mainly through rain-fed agriculture) for the production of stimulant crops for export has a positive economic impact on the national economy. However, export of 28 Gm3/yr of national water from Thailand related to rice export is at the cost of additional pressure on its blue water resources. Importing a product which has a relatively high ratio of green to blue virtual water content saves global blue water resources that generally have a higher opportunity cost than green water.

  16. Simultaneous concentration of bovine viruses and agricultural zoonotic bacteria from water using sodocalcic glass wool filters

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Infiltration and runoff from manured agricultural fields can result in livestock pathogens reaching groundwater and surface waters. Here, we measured the effectiveness of glass wool filters to simultaneously concentrate enteric viruses and bacteria of bovine origin from water. The recovery efficienc...

  17. Linking nitrogen management, seep chemistry, and stream water quality in two agricultural headwater watersheds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Riparian seepage zones in headwater agricultural watersheds represent important sources of nitrate-nitrogen (NO3-N) to surface waters, often connecting N-rich groundwater systems to streams. In this study, we examined how NO3-N concentrations in seep and stream water were affected by NO3-N processin...

  18. Estimation of surface energy fluxes using surface renewal and flux variance techniques over an advective irrigated agricultural site

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Estimation of surface energy fluxes over irrigated agriculture is needed to monitor crop water use. Estimates are commonly done using well-established techniques such as eddy covariance (EC) and weighing lysimetry, but implementing these to collect spatially distributed observations is complex and c...

  19. Agricultural drainage water management: Potential impact and implementation strategies

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The unique soil and climate of the Upper Mississippi River Basin (and the Lake Erie Basin) area provide the resources for bountiful agricultural production. Agricultural drainage (both surface and subsurface drainage) is essential for achieving economically viable crop production and management. Dra...

  20. Sustaining dry surfaces under water.

    PubMed

    Jones, Paul R; Hao, Xiuqing; Cruz-Chu, Eduardo R; Rykaczewski, Konrad; Nandy, Krishanu; Schutzius, Thomas M; Varanasi, Kripa K; Megaridis, Constantine M; Walther, Jens H; Koumoutsakos, Petros; Espinosa, Horacio D; Patankar, Neelesh A

    2015-01-01

    Rough surfaces immersed under water remain practically dry if the liquid-solid contact is on roughness peaks, while the roughness valleys are filled with gas. Mechanisms that prevent water from invading the valleys are well studied. However, to remain practically dry under water, additional mechanisms need consideration. This is because trapped gas (e.g. air) in the roughness valleys can dissolve into the water pool, leading to invasion. Additionally, water vapor can also occupy the roughness valleys of immersed surfaces. If water vapor condenses, that too leads to invasion. These effects have not been investigated, and are critically important to maintain surfaces dry under water. In this work, we identify the critical roughness scale, below which it is possible to sustain the vapor phase of water and/or trapped gases in roughness valleys - thus keeping the immersed surface dry. Theoretical predictions are consistent with molecular dynamics simulations and experiments. PMID:26282732

  1. Sustaining dry surfaces under water

    PubMed Central

    Jones, Paul R.; Hao, Xiuqing; Cruz-Chu, Eduardo R.; Rykaczewski, Konrad; Nandy, Krishanu; Schutzius, Thomas M.; Varanasi, Kripa K.; Megaridis, Constantine M.; Walther, Jens H.; Koumoutsakos, Petros; Espinosa, Horacio D.; Patankar, Neelesh A.

    2015-01-01

    Rough surfaces immersed under water remain practically dry if the liquid-solid contact is on roughness peaks, while the roughness valleys are filled with gas. Mechanisms that prevent water from invading the valleys are well studied. However, to remain practically dry under water, additional mechanisms need consideration. This is because trapped gas (e.g. air) in the roughness valleys can dissolve into the water pool, leading to invasion. Additionally, water vapor can also occupy the roughness valleys of immersed surfaces. If water vapor condenses, that too leads to invasion. These effects have not been investigated, and are critically important to maintain surfaces dry under water. In this work, we identify the critical roughness scale, below which it is possible to sustain the vapor phase of water and/or trapped gases in roughness valleys – thus keeping the immersed surface dry. Theoretical predictions are consistent with molecular dynamics simulations and experiments. PMID:26282732

  2. Denitrification of agricultural drainage line water via immobilized denitrification sludge

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Nonpoint source nitrogen is recognized as a significant water pollutant worldwide. One of the major contributors is agricultural drainage line water. One potential method of reducing this nitrogen discharge to water bodies is the use of immobilized denitrifying sludge (IDS). Our objectives were to 1...

  3. Surface Water Records of Colorado

    USGS Publications Warehouse

    U.S. Geological Survey, Water Resources Division

    1962-01-01

    The surface-water records for the 1962 water year for gaging stations and miscellaneous sites within the State of Colorado are given in this report. For convenience there are also included records for a few pertinent gaging stations in bordering States. The records were collected and computed by the Water Resources Division of the U.S. Geological Survey, under the direction of J. W. Odell, district engineer, Surface Water Branch.

  4. SURFACE WATER INTAKES

    EPA Science Inventory

    The Safe Drinking Water Information System (SDWIS) GIS layer represents the locations of public water system (PWS) facilities in NY and NJ; every PWS has one or more facilities. Data for this layer came from the Safe Drinking Water Information System/Federal version (SDWIS/FED)...

  5. Army Industrial, Landscaping, and Agricultural Water Use

    SciTech Connect

    McMordie Stoughton, Kate; Loper, Susan A.; Boyd, Brian K.

    2014-09-18

    The Pacific Northwest National Laboratory conducted a task for the Deputy Assistant Secretary of the Army to quantify the Army’s ILA water use and to help improve the data quality and installation water reporting in the Army Energy and Water Reporting System.

  6. Fragipan controls on nitrogen loss by surface and subsurface flow pathways in an upland agricultural watershed

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Improved understanding of nutrient transport by surface and subsurface flow pathways is critical to protecting water quality in agricultural watersheds. We sought to compare nitrogen loss in overland and subsurface flow on two opposing hillslopes (north versus south facing), each with contrasting so...

  7. CONSTRUCTED WETLANDS IN SUPPORT OF RIPARIAN RESTORATION: WATER QUALITY BENEFITS AND HABITAT RESTORATION IN DELAWARE AGRICULTURAL AREAS

    EPA Science Inventory

    Surface water runoff from agricultural landscapes is one of the major sources of water quality impairment in the United States. With the advent of buffer strips and conservation minded tilling practices the agricultural community has made significant reductions in overland runof...

  8. Surface wind observations affected by agricultural development over Northwest China

    NASA Astrophysics Data System (ADS)

    Han, Songjun; Tang, Qiuhong; Zhang, Xuezhen; Xu, Di; Kou, Lihang

    2016-05-01

    Meteorological stations in Northwest China are surrounded by large proportions of cultivated land. The relations between the change of surface wind speed and the cultivated land fractions (CF) within a 4 km radius at 135 meteorological stations over arid Northwest China are investigated. Stations with larger CF experienced larger declines in surface wind speed from 1960 to 2007. Compared with the wind speed variation in the Tibetan Plateau where agricultural development is negligible, stations with low CF show similar variation, whereas the wind speed at stations with large CF illustrates a sharp decrease in the 1970s–1980s, during which irrigated agriculture developed rapidly. The observed wind speed at the station surrounded by irrigated fields in the Jingtai Irrigation District, shows a rapid wind speed decrease during the same period when the irrigated area expanded. By contrast, rapid wind decrease is not observed at a nearby station with minimal influence of agricultural development.

  9. Remotely Sensed Estimates of Evapotranspiration in Agricultural Areas of Northwestern Nevada: Drought, Reliance, and Water Transfers

    NASA Astrophysics Data System (ADS)

    Bromley, Matthew

    The arid landscape of northwestern Nevada is punctuated by agricultural communities that rely on water primarily supplied by the diversion of surface waters and secondarily by groundwater resources. Annual precipitation in the form of winter snowfall largely determines the amount of surface water that is available for irrigation for the following agricultural growing season. During years of insufficient surface water supplies, particular basins can use groundwater in order to meet irrigation needs. The amount of water used to irrigate agricultural land is influenced by land use changes, such as fallowing, and water right transfers from irrigation to municipal use. To evaluate agricultural water consumption with respect to variations in weather, water supply, and land use changes, monthly estimates of evapotranspiration (ET) were derived from Landsat multispectral optical and thermal imagery over a eleven-year period (2001 to 2011) and compared to variations in weather, water supply, and land use across four hydrographic areas in northwestern Nevada. Monthly ET was estimated using a land surface energy balance model, Mapping EvapoTranspiration at high Resolution with Internalized Calibration (METRIC), using Landsat 5 and Landsat 7 imagery combined with local atmospheric water demand estimates. Estimates of net ET were created by subtracting monthly precipitation from METRIC-derived ET, and seasonal estimates were generated by combining monthly ET for April-October (the regional agricultural growing season). Results highlight that a range of geographic, climatic, hydrographic, and anthropogenic factors influence ET. Hydrographic areas such as Mason Valley have the ability to mitigate deficiencies in surface water supplies by pumping supplemental groundwater, thereby resulting in low annual variability in ET. Conversely, the community of Lovelock has access to limited upstream surface water storage and is restricted by groundwater that is saline and unsuitable for

  10. CONNECTICUT SURFACE WATER QUALITY CLASSIFICATIONS

    EPA Science Inventory

    This is a 1:24,000-scale datalayer of Surface Water Quality Classifications for Connecticut. It is comprised of two 0Shapefiles with line and polygon features. Both Shapefiles must be used together with the Hydrography datalayer. The polygon Shapefile includes surface water qual...

  11. [Research progress on water footprint in agricultural products].

    PubMed

    Lu, Yang; Liu, Xiu-wei; Zhang, Xi-ying

    2015-10-01

    Water is one of the important resources in human activities. Scientifically and rationally evaluating the effects of human activities on water resources is important for sustainable water resource management. The innovative concepts of water footprint (WF) distinguished the human water consumption into green water, blue water and grey water which extended the evaluation methods in sustainable utilization of water resources. Concepts of WF based on virtual water (VW) and based on life cycle assessment (LCA) both combined water quality and water quantity are now the focuses in agricultural water management researches. Theory of WF based on VW includes the calculation of green, blue and grey WF as well as the evaluation of the sustainability of water environment. Theory of WF based on LCA reflects the overall impact of consumptive and degradative water use on the environment. The purpose of this article was to elaborate the research progresses in theoretical calculation methods and environmental sustainability assessment of the two water footprint theories and then to analyze the differentiation of these two methodologies in describing the consumptive water use in agriculture and its effects on environment. Finally, some future research aspects on water footprint were provided. PMID:26995933

  12. Organic matter composition of soil macropore surfaces under different agricultural management practices

    NASA Astrophysics Data System (ADS)

    Glæsner, Nadia; Leue, Marin; Magid, Jacob; Gerke, Horst H.

    2016-04-01

    Understanding the heterogeneous nature of soil, i.e. properties and processes occurring specifically at local scales is essential for best managing our soil resources for agricultural production. Examination of intact soil structures in order to obtain an increased understanding of how soil systems operate from small to large scale represents a large gap within soil science research. Dissolved chemicals, nutrients and particles are transported through the disturbed plow layer of agricultural soil, where after flow through the lower soil layers occur by preferential flow via macropores. Rapid movement of water through macropores limit the contact between the preferentially moving water and the surrounding soil matrix, therefore contact and exchange of solutes in the water is largely restricted to the surface area of the macropores. Organomineral complex coated surfaces control sorption and exchange properties of solutes, as well as availability of essential nutrients to plant roots and to the preferentially flowing water. DRIFT (Diffuse Reflectance infrared Fourier Transform) Mapping has been developed to examine composition of organic matter coated macropores. In this study macropore surfaces structures will be determined for organic matter composition using DRIFT from a long-term field experiment on waste application to agricultural soil (CRUCIAL, close to Copenhagen, Denmark). Parcels with 5 treatments; accelerated household waste, accelerated sewage sludge, accelerated cattle manure, NPK and unfertilized, will be examined in order to study whether agricultural management have an impact on the organic matter composition of intact structures.

  13. Surface hardening of cutting elements agricultural machinery vibro arc plasma

    NASA Astrophysics Data System (ADS)

    Sharifullin, S. N.; Adigamov, N. R.; Adigamov, N. N.; Solovev, R. Y.; Arakcheeva, K. S.

    2016-01-01

    At present, the state technical policy aimed at the modernization of worn equipment, including agriculture, based on the use of high-performance technology called nanotechnology. By upgrading worn-out equipment meant restoring it with the achievement of the above parameters passport. The existing traditional technologies are not suitable for the repair of worn-out equipment modernization. This is especially true of imported equipment. Out here alone - is the use of high-performance technologies. In this paper, we consider the use of vibro arc plasma for surface hardening of cutting elements of agricultural machinery.

  14. Agricultural Water Conservation via Conservation Tillage and Thermal Infrared

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In Georgia water conservation is an issue that involves all citizens. Within the agricultural row crop community, water is a very important part of producing a harvestable and profitable product. Although irrigation is used only as a supplement to natural rainfall, it can greatly affect crop yield...

  15. Thermal Infrared Imagery for Better Water Conservation in Agricultural Fields

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Water conservation is an issue that involves all citizens in Georgia. Within the agricultural row crop community, water is a very important part of producing a harvestable and profitable product. Although irrigation is used only as a supplement to natural rainfall, it can greatly affect crop yield...

  16. Integrating agricultural policies and water policies under water supply and climate uncertainty

    NASA Astrophysics Data System (ADS)

    MejíAs, Patricia; Varela-Ortega, Consuelo; Flichman, Guillermo

    2004-07-01

    Understanding the interactions of water and agricultural policies is crucial for achieving an efficient management of water resources. In the EU, agricultural and environmental policies are seeking to converge progressively toward mutually compatible objectives and, in this context, the recently reformed Common Agricultural Policy (CAP) and the EU Water Framework Directive constitute the policy framework in which irrigated agriculture and hence water use will evolve. In fact, one of the measures of the European Water Directive is to establish a water pricing policy for improving water use and attaining a more efficient water allocation. The aim of this research is to investigate the irrigators' responses to these changing policy developments in a self-managed irrigation district in southern Spain. A stochastic programming model has been developed to estimate farmers' response to the application of water pricing policies in different agricultural policy scenarios when water availability is subject to varying climate conditions and water storage capacity in the district's reservoir. Results show that irrigators are price-responsive, but a similar water-pricing policy in different agricultural policy options could have distinct effects on water use, farmers' income, and collected revenue by the water authority. Water availability is a critical factor, and pricing policies are less effective for reducing water consumption in drought years. Thus there is a need to integrate the objectives of water policies within the objectives of the CAP programs to avoid distortion effects and to seek synergy between these two policies.

  17. Volumetric Pricing of Agricultural Water Supplies: A Case Study

    NASA Astrophysics Data System (ADS)

    Griffin, Ronald C.; Perry, Gregory M.

    1985-07-01

    Models of water consumption by rice producers are conceptualized and then estimated using cross-sectional time series data obtained from 16 Texas canal operators for the years 1977-1982. Two alternative econometric models demonstrate that both volumetric and flat rate water charges are strongly and inversely related to agricultural water consumption. Nonprice conservation incentives accompanying flat rates are hypothesized to explain the negative correlation of flat rate charges and water consumption. Application of these results suggests that water supply organizations in the sample population converting to volumetric pricing will generally reduce water consumption.

  18. Surface Water Response Modeling

    EPA Science Inventory

    During response to spills, or for facility planning, the vulnerability of downstream water resources is a major concern. How long and at what concentration do spilled contaminants reach downstream receptors? Models have the potential to answer these questions, but only if they ...

  19. Agricultural water demand, water quality and crop suitability in Souk-Alkhamis Al-Khums, Libya

    NASA Astrophysics Data System (ADS)

    Abunnour, Mohamed Ali; Hashim, Noorazuan Bin Md.; Jaafar, Mokhtar Bin

    2016-06-01

    Water scarcity, unequal population distribution and agricultural activities increased in the coastal plains, and the probability of seawater intrusion with ground water. According to this, the quantitative and qualitative deterioration of underground water quality has become a potential for the occurrence, in addition to the decline in agricultural production in the study area. This paper aims to discover the use of ground water for irrigation in agriculture and their suitability and compatibility for agricultural. On the other hand, the quality is determines by the cultivated crops. 16 random samples of regular groundwater are collected and analyzed chemically. Questionnaires are also distributed randomly on regular basis to farmers.

  20. Soil Water and Shallow Groundwater Relations in an Agricultural Hillslope

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Shallow water tables contribute to soil water variations under rolling topography, and soil properties contribute to shallow water table fluctutations. Preferential flow through large soil pores can cause a rise in the water table with little increase in soil water except near the soil surface. Late...

  1. Measuring Surface Water From Space

    NASA Astrophysics Data System (ADS)

    Partsch, J.; Alsdorf, D.; Rodriguez, E.; Lettenmaier, D.; Mognard, N.; Participants, T.

    2006-12-01

    Surface fresh water is essential for life, yet we have surprisingly poor knowledge of the spatial and temporal dynamics of surface fresh water discharge and changes in storage globally. For example, we are unable to answer such basic questions as "What is the spatial and temporal variability of water stored on and near the surface of all continents?" Furthermore, key societal issues, such as the susceptibility of life to flood hazards, cannot be answered with the current global, in-situ networks designed to observe river discharge at points but not flood events. The measurements required to answer these hydrologic questions are surface water area, the elevation of the water surface (h), its slope (dh/dx), and temporal change (dh/dt). Advances in remote sensing hydrology, particularly over the past 10 years and even more recently, have demonstrated that these hydraulic variables can be measured reliably from orbiting platforms. Measurements of inundated area have been used to varying degrees of accuracy as proxies for discharge, but are successful only when in-situ data are available for calibration and fail to indicate the dynamic topography of water surfaces. Radar altimeters have a rich, multi-decadal history of successfully measuring elevations of the ocean surface and are now also accepted as capable tools for measuring h along orbital profiles crossing fresh water bodies. However, altimeters are profiling tools which, because of their orbital spacings, miss too many fresh water bodies to be useful hydrologically. High spatial resolution images of dh/dt have been observed with interferometric synthetic aperture radar (SAR), but the method requires emergent vegetation to scatter radar pulses back to the receiving antenna. Essentially, existing spaceborne methods have been used to measure components of surface water hydraulics, but none of the technologies can singularly supply the water volume and hydraulic measurements that are needed to accurately model the

  2. Climate Change Impacts on Water Resources and Irrigated Agriculture in the Central Valley of California

    NASA Astrophysics Data System (ADS)

    Winter, J.; Young, C. A.; Azarderakhsh, M.; Ruane, A. C.; Rosenzweig, C.

    2013-12-01

    Agricultural productivity is strongly dependent on the availability of water, necessitating accurate projections of water resources, the allocation of water resources across competing sectors, and the effects of insufficient water resources on crops to assess the impacts of climate change on agricultural productivity. To explore the interface of water and agriculture in California's Central Valley, the Decision Support System for Agrotechnology Transfer (DSSAT) crop model was coupled to the Water Evaluation and Planning System (WEAP) water resources model, deployed over the region, and run using both historical and future climate scenarios. This coupling brings water supply constraints to DSSAT and sophisticated agricultural water use, management, and diagnostics to WEAP. A 30-year simulation of WEAP-DSSAT forced using a spatially interpolated observational dataset was run from 1980-2009. Moderate Resolution Imaging Spectroradiometer Surface Resistance and Evapotranspiration (MOD16) and Terrestrial Observation and Prediction System (TOPS) data were used to evaluate WEAP-DSSAT evapotranspiration calculations. Overall WEAP-DSSAT reasonably captures the seasonal cycle of observed evapotranspiration, but some catchments contain significant biases. Future climate scenarios were constructed by adjusting the spatially interpolated observational dataset with North American Regional Climate Change Assessment Program differences between future (2050-2069) and historical (1980-1999) regional climate model simulations of precipitation and temperature. Generally, within the Central Valley temperatures warm by approximately 2°C, precipitation remains constant, and crop water use efficiency increases. The overall impacts of future climate on irrigated agricultural yields varies across the Central Valley and is highly dependent on crop, water resources demand assumptions, and agricultural management.

  3. Climate, water and agriculture in the Tropics

    SciTech Connect

    Jackson, I.J.

    1989-01-01

    The broad view is established with a functional definition of the tropics to include the area lying within the region of the easterly trade winds and its extension to extratropical regions that are affected by tropical phenomena such as the southwest Indian monsoon and hurricanes. In the first five chapters Jackson discusses atmospheric water largely in physical terms-its origin and transport with relation to general circulation patterns and precipitation characteristics such as frequency, duration, and intensity, which are as important as total rainfall in the consideration of runoff, biological productivity, and land utilization. In the remainder of the book water-soil-plant relationships are discussed generally and specifically for selected crops and regions. Popular emotional appears currently decry the destruction of tropical wet forests. Jackson makes it clear that tropical lands exhibit a rich variation in climates and that problems of exploitation rooted in cultures, economics, politics, and population growth cannot be solved by the simple introduction of temperate zone science and technology. This volume is a hybrid between an intermediate level textbook and a review article for the knowledgeable investigator, planner, or administrator, and the values to be found in it will vary with the background and interests of the reader. A reference list of more than 800 titles, perhaps half of them dated in the present decade, is a major asset, especially when coupled with extensive author and subject indexes.

  4. Assessment of Filter Materials for Removal of Contaminants From Agricultural Drainage Waters

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fertilizer nutrients and pesticides applied on farm fields, especially in the Midwest U.S., are commonly intercepted by buried agricultural drainage pipes and then discharged into local streams and lakes, oftentimes resulting in an adverse environmental impact on these surface water bodies. Low cost...

  5. RESEARCH NEEDS TO SUSTAIN AGRICULTURE ON THE HIGH PLAINS WITH LIMITED IRRIGATION WATER SUPPLIES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Irrigated agriculture in the West is facing declining water supplies. Many aquifers are being pumped at non-sustainable rates. Increasing realization of the inter-connectivity of surface and groundwater supplies are resulting in legal restrictions on groundwater use. Downstream (or upstream) user...

  6. Annual precipitation and effects of runoff-nutrient from agricultural watersheds on water quality

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Declining surface water quality from agricultural nonpoint sources is of great concern across the Platte river basin in Nebraska. Recent changes in the earth climate create abrupt changes in domestic weather (i.e., precipitation, temperature, etc.) which can alter the impact of these nonpoint source...

  7. Policy and Ethics In Agricultural and Ecological Water Uses.

    NASA Astrophysics Data System (ADS)

    Appelgren, Bo

    Agricultural water use accounts for about 70 percent of abstracted waters reaching 92 percent of the collective uses of all water resources when rain water is included. Agriculture is the traditional first sector and linked to a wide range of social, economic and cultural issues at local and global level that reach beyond the production of cheap food and industrial fibres. With the dominance in agricultural water uses and linkages with land use and soil conservation the sector is critical to the protection of global and local environmental values especially in sensitive dryland systems. Ethical principles related to development and nature conservation have traditionally been focused on sustainability imperatives building on precaution and preventive action or on indisputable natural systems values, but are by necessity turning more and more towards solidarity-based risk management approaches. Policy and management have in general failed to consider social dimensions with solidarity, consistency and realism for societal acceptance and practical application. As a consequence agriculture and water related land degradation is resulting in accelerated losses in land productivity and biodiversity in dryland and in humid eco- systems. Increasingly faced with the deer social consequences in the form of large man-made hydrological disasters and with pragmatic requirements driven by drastic increases in the related social cost the preferences are moving to short-term risk management approaches with civil protection objectives. Water scarcity assessment combined with crisis diagnoses and overriding statements on demographic growth, poverty and natural resources scarcity and deteriorating food security in developing countries have become common in the last decades. Such studies are increasingly questioned for purpose, ethical integrity and methodology and lack of consideration of interdependencies between society, economy and environment and of society's capacity to adapt to

  8. Agricultural water consumption decreasing nutrient burden at Bohai Sea, China

    NASA Astrophysics Data System (ADS)

    Tong, Yindong; Wang, Xuejun; Zhen, Gengchong; Li, Ying; Zhang, Wei; He, Wei

    2016-02-01

    In this study, we discussed the impacts of human water consumption to the nutrient burden in a river estuary, and used Huanghe River as a case study. The agricultural water consumption from the Huanghe River has significantly decreased the natural water flows, and the amount of water consumption could be almost twice as high as the water entering into the estuary. According to our calculation, agricultural water usage decreased TN outflows by 6.5 × 104 Mg/year and TP outflows by 2.0 × 103 Mg/year. These account for 74% and 77% of the total output loads. It has been widely reported that the majority of the rivers in northern China were severely polluted by nutrients. Its implication on the budget of nutrient in the estuary ecosystem is not well characterized. Our study showed that the discharge of nutrients in the coast waters from polluted rivers was over concerned. Nutrients in the polluted rivers were transported back to the terrestrial systems when water was drawn for human water consumption. The magnitudes of changes in riverine nutrient discharges even exceed the water-sediment regulation trails in the Huanghe River. It has non-negligible impact on estimating the nutrient burden in costal water ecosystem.

  9. Managing agricultural phosphorus for water quality: lessons from the USA and China.

    PubMed

    Sharpley, Andrew; Wang, Xiaoyan

    2014-09-01

    The accelerated eutrophication of freshwaters and to a lesser extent some coastal waters is primarily driven by phosphorus (P) inputs. While efforts to identify and limit point source inputs of P to surface waters have seen some success, nonpoint sources remain difficult to identify, target, and remediate. As further improvements in wastewater treatment technologies becomes increasingly costly, attention has focused more on nonpoint source reduction, particularly the role of agriculture. This attention was heightened over the last 10 to 20 years by a number of highly visible cases of nutrient-related water quality degradation; including the Lake Taihu, Baltic Sea, Chesapeake Bay, and Gulf of Mexico. Thus, there has been a shift to targeted management of critical sources of P loss. In both the U.S. and China, there has been an intensification of agricultural production systems in certain areas concentrate large amounts of nutrients in excess of local crop and forage needs, which has increased the potential for P loss from these areas. To address this, innovative technologies are emerging that recycle water P back to land as fertilizer. For example, in the watershed of Lake Taihu, China one of the largest surface fresh waters for drinking water supply in China, local governments have encouraged innovation and various technical trials to harvest harmful algal blooms and use them for bio-gas, agricultural fertilizers, and biofuel production. In any country, however, the economics of remediation will remain a key limitation to substantial changes in agricultural production. PMID:25193824

  10. Occurrence and Distribution of Agricultural Pesticides and Transport Modeling in Surface and Subsurface Environments

    NASA Astrophysics Data System (ADS)

    Chu, X.; Marino, M. A.

    2007-12-01

    The use of a variety of pesticides has increased dramatically during the past decades to improve agricultural efficiency and productivity. However, these agricultural chemicals are often washed to surface waters by runoff and leached through the vadose zone to ground water, thereby polluting waters and threatening human health as well as aquatic and terrestrial ecosystems. It is of particular importance to develop effective modeling tools to assess the induced nonpoint source pollution, to regulate the use of agricultural pesticides, and to circumvent further deterioration in water quality. Different physically-based pesticide transport models, ranging from simple analytical models to semidiscrete and more rigorous numerical models, are discussed. In particular, the effects of use of pesticides on their occurrence and distribution in surface and subsurface environments are examined in this study. A windows-based integrated pesticide transport model (IPTM) is used to simulate three-phase pesticide transport and transformation and quantify spatial and temporal distributions in a coupled canopy-soil system as well as pesticide loading potential to the adjacent surface water through surface runoff and erosion. Five different pesticides (diazinon, 2,4-D acid, DBCP, simazine, and lindane) are examined. It is found that occurrence and distribution of pesticides in the environment are closely related to their use and determined by a series of pesticide transport and transformation processes. The occurrence and use of pesticides follow extremely complex and dynamic patterns that are affected by numerous factors related to their use and properties, hydrology, and agricultural activities. It is also found that changes in pesticide use (application quantity, frequency, timing, and method) may result in distinct environmental fate of pesticides in terms of their occurrence extent as well as spatial and temporal distributions.

  11. Water quality issues associated with agricultural drainage in semiarid regions

    NASA Astrophysics Data System (ADS)

    Sylvester, Marc A.

    High incidences of mortality, birth defects, and reproductive failure in waterfowl using Kesterson Reservoir in the San Joaquin Valley, Calif., have occurred because of the bioaccumulation of selenium from irrigation drainage. These circumstances have prompted concern about the quality of agriculture drainage and its potential effects on human health, fish and wildlife, and beneficial uses of water. The U.S. Geological Survey (USGS) and Lawrence Berkeley Laboratory, University of California (Berkeley, Calif.) organized a 1-day session at the 1986 AGU Fall Meeting in San Francisco, Calif., to provide an interdisciplinary forum for hydrologists, geochemists, and aquatic chemists to discuss the processes controlling the distribution, mobilization, transport, and fate of trace elements in source rocks, soils, water, and biota in semiarid regions in which irrigated agriculture occurs. The focus of t h e session was the presentation of research results on the source, distribution, movement, and fate of selenium in agricultural drainage.

  12. Managing agricultural phosphorus for water quality protection: principles for progress

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The eutrophication of aquatic systems due to diffuse pollution of agricultural phosphorus (P) is a local, even regional, water quality problem that can be found world-wide. Sustainable management of P requires prudent tempering of agronomic practices, recognizing that additional steps are often requ...

  13. Managing Delmarva Agricultural Drainage Ditches for Water Quality Protection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agricultural drainage ditches are essential for draining storm and subsurface water from farmland on the Delmarva Peninsula. Ditches are unique ecosystems, having the features of both streams and wetlands. Ditches often provide the only wetland and aquatic habitats on farmland. Ditches carry, store,...

  14. Multifunctional systems approaches to water management for agriculture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The impact of anthropogenic chemicals on water quality, wildlife, and human health has received increasing attention in recent years. One potential source of anthropogenic compounds is land-based recycling programs which apply municipal wastes (biosolids) to large tracts of agricultural land in lie...

  15. ALTERNATIVE POLICIES FOR CONTROLLING NONPOINT AGRICULTURAL SOURCES OF WATER POLLUTION

    EPA Science Inventory

    This study of policies for controlling water pollution from nonpoint agricultural sources includes a survey of existing state and Federal programs, agencies, and laws directed to the control of soil erosion. Six policies representing a variety of approaches to this pollution prob...

  16. Edge-of-field research to quantify the impacts of agricultural practices on water quality in Ohio

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Drainage is needed to sustain agricultural production to meet the demands of a growing global population, but it also transports nutrients from fields to surface water bodies. The State of Ohio is facing the tremendous challenge of maintaining agricultural production while protecting the environment...

  17. Measuring surface water from space

    NASA Astrophysics Data System (ADS)

    Alsdorf, Douglas E.; RodríGuez, Ernesto; Lettenmaier, Dennis P.

    2007-06-01

    Surface fresh water is essential for life, yet we have surprisingly poor knowledge of the spatial and temporal dynamics of surface freshwater discharge and changes in storage globally. For example, we are unable to answer such basic questions as "What is the spatial and temporal variability of water stored on and near the surface of all continents?" Furthermore, key societal issues, such as the susceptibility of life to flood hazards, cannot be answered with the current global, in situ networks designed to observe river discharge at points but not flood events. The measurements required to answer these hydrologic questions are surface water area, the elevation of the water surface (h), its slope (∂h/∂x), and temporal change (∂h/∂t). Advances in remote sensing hydrology, particularly over the past 10 years and even more recently, have demonstrated that these hydraulic variables can be measured reliably from orbiting platforms. Measurements of inundated area have been used to varying degrees of accuracy as proxies for discharge but are successful only when in situ data are available for calibration; they fail to indicate the dynamic topography of water surfaces. Radar altimeters have a rich, multidecadal history of successfully measuring elevations of the ocean surface and are now also accepted as capable tools for measuring h along orbital profiles crossing freshwater bodies. However, altimeters are profiling tools, which, because of their orbital spacings, miss too many freshwater bodies to be useful hydrologically. High spatial resolution images of ∂h/∂t have been observed with interferometric synthetic aperture radar, but the method requires emergent vegetation to scatter radar pulses back to the receiving antenna. Essentially, existing spaceborne methods have been used to measure components of surface water hydraulics, but none of the technologies can singularly supply the water volume and hydraulic measurements that are needed to accurately model

  18. Agricultural hydrology and water quality II: Introduction to the featured collection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agricultural hydrology and water quality is a multidisciplinary field devoted to understanding the interrelationship between modern agriculture and water resources. This paper summarizes a featured collection of 10 manuscripts emanating from the 2013 American Water Resources Association Specialty Co...

  19. APPLICATIONS OF AGRICULTURAL SYSTEM MODELS IN ASSESSING AND MANAGING CONTAMINATION OF THE SOIL-WATER-ATMOSPHERE CONTINUUM IN AGRICULTURE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In the last three decades, there has been a growing public concern about the adverse effects of modern agriculture on environmental quality and soil-water resources. In the mid-1980's, the USDA, Agricultural Research Service (ARS) identified the need for models of whole agricultural systems that wi...

  20. Application of Agricultural System Models in Assessing and Managing Contamination of Soil-Water-Atmosphere Continuum in Agriculture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In the last three decades, there has been a growing public concern about the adverse effects of modern agriculture on environmental quality and soil-water resources. In the mid-1980s, the USDA, Agricultural Research Service (ARS) identified the need for models of whole agricultural systems th...

  1. Can rainfed agriculture adapt to uncertainty in availability of water in Indus Basin?

    NASA Astrophysics Data System (ADS)

    Jutla, A.; Sen, S.

    2015-12-01

    Understanding impacts of hydrological and climatological functions under changing climate on regional floods, droughts as well as agricultural commodities remain a serious challenge in tropical agricultural basins. These "tropical agricultural basins" are regions where: (i) the understanding on hydrologic functions (such as precipitation, soil moisture, evapotranspiration, surface runoff, vegetation) are not well established; (ii) increasing population is at the convergence of rural and urban boundaries; (iii) resilience and sustainability of the water resources under different climatic conditions is unknown; and, (iv) agriculture is the primary occupation for majority of the population. More than 95% of the farmed lands in tropical regions are rainfed and 60% of total agricultural production in South Asia relying on seasonal rainfall. Tropical regions frequently suffer from unexpected droughts and sudden flash floods, resulting in massive losses in human lives and affecting regional economy. Prediction of frequency, intensity and magnitude of floods in tropical regions is still a subject of debate and research. A clear example is from the massive floods in the Eastern Indus River in July 2010 that submerged 17 million acre of fertile cropland. Yet, seasonal droughts, such as 2014 rain deficits in Indus Basin, had no effects on annual crop yields - thus creating a paradox. Large amounts of groundwater is being used to supplement water needs for crops during drought conditions, leading to oversubscription of natural aquifers. Key reason that rainfed agriculture is relying heavily on groundwater is because of the uncertainty in timing and distribution of precipitation in the tropical regions, where such data are not routinely collected as well as the basins are transnational, thus limiting sharing of data. Assessment of availability of water for agricultural purposes a serious challenge in tropical regions. This study will provide a framework for using multi

  2. A survey of groundwater levels and hydrogeochemistry in irrigated fields in the Karamay Agricultural Development Area, northwest China: Implications for soil and groundwater salinity resulting from surface water transfer for irrigation

    NASA Astrophysics Data System (ADS)

    Han, Dongmei; Song, Xianfang; Currell, Matthew J.; Cao, Guoliang; Zhang, Yinghua; Kang, Yuehu

    2011-08-01

    SummaryAnalysis of the water budget, along with hydrochemistry and stable isotopes in shallow groundwater were carried out in the Karamay Agricultural Development Area (KADA) in order to assess the impact of transfer of irrigation water from the IrtySh River, in particular in relation to the mechanisms of salinization and the nature of the water table regime. In terms of aquifer dynamics, the addition of the irrigation water without any groundwater abstraction has caused a sharp rise in the water table is and the development of serious soil salinity, together with an almost complete attenuation of inter-seasonal water table oscillations. The mean rise in the groundwater table from September 1997 to October 2009 was 6.9 m, representing an accumulated total water storage change of close to 150 million cubic meters. The analysis of aquifer water budget shows that infiltration of irrigation water occupied over 90% of the total recharge of the groundwater in the KADA. Sources of groundwater recharge and mechanisms of salinization in the KADA were also investigated using geochemical and isotopic techniques. The groundwater is characterized by Cl(SO 4)-Na type, generally becoming more Na and Cl dominated with increasing salinity. The total dissolved solids (TDS) content of the groundwater ranges from 0.5 g/L to over 65 g/L, with greater TDS values in areas of low topographic relief and shallow water tables. Where the sediments are more permeable (e.g. due to the presence of palaeochannels), TDS values are generally lower and the seasonal water table fluctuations greater. The ratios of K/Cl, Ca/Cl, Na/Cl, and Mg/Cl decrease with increasing Cl - concentrations especially in the shallow groundwater from 10 to 15 m depth, indicating hydrogeochemical evolution via minor water-rock interaction (feldspar weathering) and significant evaporation. The stable isotopic compositions show a characteristic evaporation effect in the shallow groundwater and confirm that direct

  3. Denitrification of agricultural drainage line water via immobilized denitrification sludge.

    PubMed

    Hunt, Patrick G; Matheny, Terry A; Ro, Kyoung S; Stone, Kenneth C; Vanotti, Matias B

    2008-07-15

    Nonpoint source nitrogen is recognized as a significant water pollutant worldwide. One of the major contributors is agricultural drainage line water. A potential method of reducing this nitrogen discharge to water bodies is the use of immobilized denitrifying sludge (IDS). Our objectives were to (1) produce an effective IDS, (2) determine the IDS reaction kinetics in laboratory column bioreactors, and (3) test a field bioreactor for nitrogen removal from agricultural drainage line water. We developed a mixed liquor suspended solid (MLSS) denitrifying sludge using inoculant from an overland flow treatment system. It had a specific denitrification rate of 11.4 mg NO(3)-N g(-1) MLSS h(-1). We used polyvinyl alcohol (PVA) to immobilize this sludge and form IDS pellets. When placed in a 3.8-L column bioreactor, the IDS had a maximum removal rate (K(MAX)) of 3.64 mg NO(3)-N g(-1) pellet d(-1). In a field test with drainage water containing 7.8 mg NO(3)-N L(-1), 50% nitrogen removal was obtained with a 1 hr hydraulic retention time. Expressed as a 1 m(3) cubically-shaped bioreactor, the nitrogen removal rate would be 94 g NO(3)-N m(-2)d(-1), which is dramatically higher than treatment wetlands or passive carbonaceous bioreactors. IDS bioreactors offer potential for reducing nitrogen discharge from agricultural drainage lines. More research is needed to develop the bioreactors for agricultural use and to devise effective strategies for their implementation with other emerging technologies for improved water quality on both watershed and basin scales. PMID:18569323

  4. Agricultural Impacts on Water Resources: Recommendations for Successful Applied Research

    NASA Astrophysics Data System (ADS)

    Harmel, D.

    2014-12-01

    We, as water resource professionals, are faced with a truly monumental challenge - that is feeding the world's growing population and ensuring it has an adequate supply of clean water. As researchers and educators it is good for us to regularly remember that our research and outreach efforts are critical to people around the world, many of whom are desperate for solutions to water quality and supply problems and their impacts on food supply, land management, and ecosystem protection. In this presentation, recommendations for successful applied research on agricultural impacts on water resources will be provided. The benefits of building multidisciplinary teams will be illustrated with examples related to the development and world-wide application of the ALMANAC, SWAT, and EPIC/APEX models. The value of non-traditional partnerships will be shown by the Soil Health Partnership, a coalition of agricultural producers, chemical and seed companies, and environmental advocacy groups. The results of empowering decision-makers with useful data will be illustrated with examples related to bacteria source and transport data and the MANAGE database, which contains runoff nitrogen and phosphorus data for cultivated, pasture, and forest land uses. The benefits of focusing on sustainable solutions will be shown through examples of soil testing, fertilizers application, on-farm profit analysis, and soil health assessment. And the value of welcoming criticism will be illustrated by the development of a framework to estimate and publish uncertainty in measured discharge and water quality data. The good news for researchers is that the agricultural industry is faced with profitability concerns and the need to wisely utilize soil and water resources, and simultaneously state and federal agencies crave sound-science to improve decision making, policy, and regulation. Thus, the audience for and beneficiaries of agricultural research are ready and hungry for applied research results.

  5. Activities affecting surface water resources: A general overview

    SciTech Connect

    Not Available

    1990-01-01

    In November 1987, P.E.I. signed a federal/provincial work-sharing arrangement on water resource management focusing on groundwater pollution, surface water degradation and estuarine eutrophication. The surface water program was designed to identify current surface water uses and users within 12 major watersheds across the Island containing 26 individual rivers, as well as problems arising due to practices that degrade the quality of surface water and restricts its value to other user groups. This report presents a general overview of the program, covering the general characteristics of the Island; operations in agriculture, fish and wildlife, forestry, recreation, fisheries, and industry; alterations of natural features of waterways; wetlands; additional watershed activities such as hydrometric stations and subdivision development; and activities affecting surface water resources such as sedimentation sources, pollution point sources and instream obstructions.

  6. Land use policy and agricultural water management of the previous half of century in Africa

    NASA Astrophysics Data System (ADS)

    Valipour, Mohammad

    2015-12-01

    This paper examines land use policy and agricultural water management in Africa from 1962 to 2011. For this purpose, data were gathered from Food and Agriculture Organization of the United Nations (FAO) and the World Bank Group. Using the FAO database, ten indices were selected: permanent crops to cultivated area (%), rural population to total population (%), total economically active population in agriculture to total economically active population (%), human development index, national rainfall index (mm/year), value added to gross domestic product by agriculture (%), irrigation water requirement (mm/year), percentage of total cultivated area drained (%), difference between national rainfall index and irrigation water requirement (mm/year), area equipped for irrigation to cultivated area or land use policy index (%). These indices were analyzed for all 53 countries in the study area and the land use policy index was estimated by two different formulas. The results show that value of relative error is <20 %. In addition, an average index was calculated using various methods to assess countries' conditions for agricultural water management. Ability of irrigation and drainage systems was studied using other eight indices with more limited information. These indices are surface irrigation (%), sprinkler irrigation (%), localized irrigation (%), spate irrigation (%), agricultural water withdrawal (10 km3/year), conservation agriculture area as percentage of cultivated area (%), percentage of area equipped for irrigation salinized (%), and area waterlogged by irrigation (%). Finally, tendency of farmers to use irrigation systems for cultivated crops has been presented. The results show that Africa needs governments' policy to encourage farmers to use irrigation systems and raise cropping intensity for irrigated area.

  7. Estimating Hydrologic Fluxes, Crop Water Use, and Agricultural Land Area in China using Data Assimilation

    NASA Astrophysics Data System (ADS)

    Smith, Tiziana; McLaughlin, Dennis B.; Hoisungwan, Piyatida

    2016-04-01

    Crop production has significantly altered the terrestrial environment by changing land use and by altering the water cycle through both co-opted rainfall and surface water withdrawals. As the world's population continues to grow and individual diets become more resource-intensive, the demand for food - and the land and water necessary to produce it - will continue to increase. High-resolution quantitative data about water availability, water use, and agricultural land use are needed to develop sustainable water and agricultural planning and policies. However, existing data covering large areas with high resolution are susceptible to errors and can be physically inconsistent. China is an example of a large area where food demand is expected to increase and a lack of data clouds the resource management dialogue. Some assert that China will have insufficient land and water resources to feed itself, posing a threat to global food security if they seek to increase food imports. Others believe resources are plentiful. Without quantitative data, it is difficult to discern if these concerns are realistic or overly dramatized. This research presents a quantitative approach using data assimilation techniques to characterize hydrologic fluxes, crop water use (defined as crop evapotranspiration), and agricultural land use at 0.5 by 0.5 degree resolution and applies the methodology in China using data from around the year 2000. The approach uses the principles of water balance and of crop water requirements to assimilate existing data with a least-squares estimation technique, producing new estimates of water and land use variables that are physically consistent while minimizing differences from measured data. We argue that this technique for estimating water fluxes and agricultural land use can provide a useful basis for resource management modeling and policy, both in China and around the world.

  8. Global impacts of conversions from natural to agricultural ecosystems on water resources: Quantity versus quality

    USGS Publications Warehouse

    Scanlon, B.R.; Jolly, I.; Sophocleous, M.; Zhang, L.

    2007-01-01

    [1] Past land use changes have greatly impacted global water resources, with often opposing effects on water quantity and quality. Increases in rain-fed cropland (460%) and pastureland (560%) during the past 300 years from forest and grasslands decreased evapotranspiration and increased recharge (two orders of magnitude) and streamflow (one order of magnitude). However, increased water quantity degraded water quality by mobilization of salts, salinization caused by shallow water tables, and fertilizer leaching into underlying aquifers that discharge to streams. Since the 1950s, irrigated agriculture has expanded globally by 174%, accounting for ???90% of global freshwater consumption. Irrigation based on surface water reduced streamflow and raised water tables resulting in waterlogging in many areas (China, India, and United States). Marked increases in groundwater-fed irrigation in the last few decades in these areas has lowered water tables (???1 m/yr) and reduced streamflow. Degradation of water quality in irrigated areas has resulted from processes similar to those in rain-fed agriculture: salt mobilization, salinization in waterlogged areas, and fertilizer leaching. Strategies for remediating water resource problems related to agriculture often have opposing effects on water quantity and quality. Long time lags (decades to centuries) between land use changes and system response (e.g., recharge, streamflow, and water quality), particularly in semiarid regions, mean that the full impact of land use changes has not been realized in many areas and remediation to reverse impacts will also take a long time. Future land use changes should consider potential impacts on water resources, particularly trade-offs between water, salt, and nutrient balances, to develop sustainable water resources to meet human and ecosystem needs. Copyright 2007 by the American Geophysical Union.

  9. A socio-hydrologic model of coupled water-agriculture dynamics with emphasis on farm size.

    NASA Astrophysics Data System (ADS)

    Brugger, D. R.; Maneta, M. P.

    2015-12-01

    Agricultural land cover dynamics in the U.S. are dominated by two trends: 1) total agricultural land is decreasing and 2) average farm size is increasing. These trends have important implications for the future of water resources because 1) growing more food on less land is due in large part to increased groundwater withdrawal and 2) larger farms can better afford both more efficient irrigation and more groundwater access. However, these large-scale trends are due to individual farm operators responding to many factors including climate, economics, and policy. It is therefore difficult to incorporate the trends into watershed-scale hydrologic models. Traditional scenario-based approaches are valuable for many applications, but there is typically no feedback between the hydrologic model and the agricultural dynamics and so limited insight is gained into the how agriculture co-evolves with water resources. We present a socio-hydrologic model that couples simplified hydrologic and agricultural economic dynamics, accounting for many factors that depend on farm size such as irrigation efficiency and returns to scale. We introduce an "economic memory" (EM) state variable that is driven by agricultural revenue and affects whether farms are sold when land market values exceed expected returns from agriculture. The model uses a Generalized Mixture Model of Gaussians to approximate the distribution of farm sizes in a study area, effectively lumping farms into "small," "medium," and "large" groups that have independent parameterizations. We apply the model in a semi-arid watershed in the upper Columbia River Basin, calibrating to data on streamflow, total agricultural land cover, and farm size distribution. The model is used to investigate the sensitivity of the coupled system to various hydrologic and economic scenarios such as increasing market value of land, reduced surface water availability, and increased irrigation efficiency in small farms.

  10. Cell-based Metabolomics for Assessing Chemical Exposure and Toxicity of Environmental Surface Waters

    EPA Science Inventory

    Waste water treatment plants (WWTPs), concentrated animal feeding operations (CAFOs), mining activities, and agricultural operations release contaminants that negatively affect surface water quality. Traditional methods using live animals/fish to monitor/assess contaminant exposu...

  11. Cell-based metabolomics for assessing chemical exposure and toxicity of environmental surface waters (presentation)

    EPA Science Inventory

    Introduction: Waste water treatment plants (WWTPs), concentrated animal feeding operations (CAFOs), mining activities, and agricultural operations release contaminants that negatively affect surface water quality. Traditional methods using live animals (e.g. fish) to monitor/as...

  12. Spatial Scaling Assessment of Surface Soil Moisture Estimations Using Remotely Sensed Data for Precision Agriculture

    NASA Astrophysics Data System (ADS)

    Hassan Esfahani, L.; Torres-Rua, A. F.; Jensen, A.; McKee, M.

    2014-12-01

    Airborne and Landsat remote sensing are promising technologies for measuring the response of agricultural crops to variations in several agricultural inputs and environmental conditions. Of particular significance to precision agriculture is surface soil moisture, a key component of the soil water balance, which addresses water and energy exchanges at the surface/atmosphere interface and affects vegetation health. Its estimation using the spectral reflectance of agricultural fields could be of value to agricultural management decisions. While top soil moisture can be estimated using radiometric information from aircraft or satellites and data mining techniques, comparison of results from two different aerial platforms might be complicated because of the differences in spatial scales (high resolution of approximately 0.15m versus coarser resolutions of 30m). This paper presents a combined modeling and scale-based approach to evaluate the impact of spatial scaling in the estimation of surface soil moisture content derived from remote sensing data. Data from Landsat 7 ETM+, Landsat 8 OLI and AggieAirTM aerial imagery are utilized. AggieAirTM is an airborne remote sensing platform developed by Utah State University that includes an autonomous Unmanned Aerial System (UAS) which captures radiometric information at visual, near-infrared, and thermal wavebands at spatial resolutions of 0.15 m or smaller for the optical cameras and about 0.6 m or smaller for the thermal infrared camera. Top soil moisture maps for AggieAir and Landsat are developed and statistically compared at different scales to determine the impact in terms of quantitative predictive capability and feasibility of applicability of results in improving in field management.

  13. Improving Agricultural Water Resources Management Using Ground-based Infrared Thermometry

    NASA Astrophysics Data System (ADS)

    Taghvaeian, S.

    2014-12-01

    Irrigated agriculture is the largest user of freshwater resources in arid/semi-arid parts of the world. Meeting rapidly growing demands in food, feed, fiber, and fuel while minimizing environmental pollution under a changing climate requires significant improvements in agricultural water management and irrigation scheduling. Although recent advances in remote sensing techniques and hydrological modeling has provided valuable information on agricultural water resources and their management, real improvements will only occur if farmers, the decision makers on the ground, are provided with simple, affordable, and practical tools to schedule irrigation events. This presentation reviews efforts in developing methods based on ground-based infrared thermometry and thermography for day-to-day management of irrigation systems. The results of research studies conducted in Colorado and Oklahoma show that ground-based remote sensing methods can be used effectively in quantifying water stress and consequently triggering irrigation events. Crop water use estimates based on stress indices have also showed to be in good agreement with estimates based on other methods (e.g. surface energy balance, root zone soil water balance, etc.). Major challenges toward the adoption of this approach by agricultural producers include the reduced accuracy under cloudy and humid conditions and its inability to forecast irrigation date, which is a critical knowledge since many irrigators need to decide about irrigations a few days in advance.

  14. Agricultural practices and irrigation water demand in Uttar Pradesh

    NASA Astrophysics Data System (ADS)

    O'Keeffe, J.; Buytaert, W.; Brozovic, N.; Mijic, A.

    2013-12-01

    Changes in farming practices within Uttar Pradesh, particularly advances in irrigation technology, have led to a significant drop in water tables across the region. While the acquisition of monitoring data in India is a challenge, current water use practices point towards water overdraught. This is exacerbated by government and state policies and practices, including the subsidising of electricity, seeds and fertilizer, and an agreement to buy all crops grown, promoting the over use of water resources. Taking India's predicted population growth, increases in industrialisation and climate change into account, both farmland and the water resources it depends upon will be subject to increased pressures in the future. This research is centred around irrigation demands on water resources within Uttar Pradesh, and in particular, quantifying those demands both spatially and temporally. Two aspects of this will be presented; the quantification of irrigation water applied and the characterisation of the spatial heterogeneity of water use practices. Calculating the volumes of applied irrigation water in the absence of observed data presents a major challenge and is achieved here through the use of crop models. Regional crop yields provided by statistical yearbooks are replicated by the crop models AquaCrop and InfoCrop, and by doing so the amount of irrigation water needed to produce the published yields is quantified. In addition, proxy information, for example electrical consumption for agricultural use, is used to verify the likely volumes of water abstracted from tubewells. Statistical analyses of borehole distribution and the characterisation of the spatial heterogeneity of water use practices, particularly farmer decision making, collected during a field trip are also presented. The evolution of agricultural practices, technological advancement and water use for irrigation is reconstructed through the use of multiple regression and principle component analysis

  15. Two Surface Temperature Retrieval Methods Compared Over Agricultural Lands

    NASA Technical Reports Server (NTRS)

    French, Andrew N.; Schmugge, Thomas J.; Jacob, Frederic; Ogawa, Kenta; Houser, Paul R. (Technical Monitor)

    2002-01-01

    Accurate, spatially distributed surface temperatures are required for modeling evapotranspiration (ET) over agricultural fields under wide ranging conditions, including stressed and unstressed vegetation. Modeling approaches that use surface temperature observations, however, have the burden of estimating surface emissivities. Emissivity estimation, the subject of much recent research, is facilitated by observations in multiple thermal infrared bands. But it is nevertheless a difficult task. Using observations from a multiband thermal sensor, the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER), estimated surface emissivities and temperatures are retrieved in two different ways: the temperature emissivity separation approach (TES) and the normalized emissivity approach (NEM). Both rely upon empirical relationships, but the assumed relationships are different. TES relies upon a relationship between the minimum spectral emissivity and the range of observed emissivities. NEM relies upon an assumption that at least one thermal band has a pre-determined emissivity (close to 1.0). The benefits and consequences of each approach will be demonstrated for two different landscapes: one in central Oklahoma, USA and another in southern New Mexico.

  16. Global analysis of urban surface water supply vulnerability

    NASA Astrophysics Data System (ADS)

    Padowski, Julie C.; Gorelick, Steven M.

    2014-10-01

    This study presents a global analysis of urban water supply vulnerability in 71 surface-water supplied cities, with populations exceeding 750 000 and lacking source water diversity. Vulnerability represents the failure of an urban supply-basin to simultaneously meet demands from human, environmental and agricultural users. We assess a baseline (2010) condition and a future scenario (2040) that considers increased demand from urban population growth and projected agricultural demand. We do not account for climate change, which can potentially exacerbate or reduce urban supply vulnerability. In 2010, 35% of large cities are vulnerable as they compete with agricultural users. By 2040, without additional measures 45% of cities are vulnerable due to increased agricultural and urban demands. Of the vulnerable cities in 2040, the majority are river-supplied with mean flows so low (1200 liters per person per day, l/p/d) that the cities experience ‘chronic water scarcity’ (1370 l/p/d). Reservoirs supply the majority of cities facing individual future threats, revealing that constructed storage potentially provides tenuous water security. In 2040, of the 32 vulnerable cities, 14 would reduce their vulnerability via reallocating water by reducing environmental flows, and 16 would similarly benefit by transferring water from irrigated agriculture. Approximately half remain vulnerable under either potential remedy.

  17. Denitrification in the shallow ground water of a tile-drained, agricultural watershed

    USGS Publications Warehouse

    Mehnert, E.; Hwang, H.-H.; Johnson, T.M.; Sanford, R.A.; Beaumont, W.C.; Holm, T.R.

    2007-01-01

    Nonpoint-source pollution of surface water by N is considered a major cause of hypoxia. Because Corn Belt watersheds have been identified as major sources of N in the Mississippi River basin, the fate and transport of N from midwestern agricultural watersheds have received considerable interest. The fate and transport of N in the shallow ground water of these watersheds still needs additional research. Our purpose was to estimate denitrification in the shallow ground water of a tile-drained, Corn Belt watershed with fine-grained soils. Over a 3-yr period, N was monitored in the surface and ground water of an agricultural watershed in central Illinois. A significant amount of N was transported past the tile drains and into shallow ground water. The ground water nitrate was isotopically heavier than tile drain nitrate, which can be explained by denitrification in the subsurface. Denitrifying bacteria were found at depths to 10 m throughout the watershed. Laboratory and push-pull tests showed that a significant fraction of nitrate could be denitrified rapidly. We estimated that the N denitrified in shallow ground water was equivalent to 0.3 to 6.4% of the applied N or 9 to 27% of N exported via surface water. These estimates varied by water year and peaked in a year of normal precipitation after 2 yr of below average precipitation. Three years of monitoring data indicate that shallow ground water in watersheds with fine-grained soils may be a significant N sink compared with N exported via surface water. ?? ASA, CSSA, SSSA.

  18. Agricultural pesticides in six drainage basins used for public water supply in New Jersey, 1990

    USGS Publications Warehouse

    Ivahnenko, Tamara; Buxton, D.E.

    1994-01-01

    A reconnaissance study of six drainage basins in New Jersey was conducted to evaluate the presence of pesticides from agricultural runoff in surface water. In the first phase of the study, surface-water public-supply drainage basins throughout New Jersey that could be affected by pesticide applications were identified by use of a Geographic Information System. Six basins--Lower Mine Hill Reservoir, South Branch of the Raritan River, Main Branch of the Raritan River, Millstone River, Manasquan River, and Matchaponix Brook--were selected as those most likely to be affected by pesticides on the basis of calculated pesticide-application rates and percentage of agricultural land. The second phase of the project was a short-term water-quality reconnaissance of the six drainage basins to determine whether pesticides were present in the surface waters. Twenty-eight surface-water samples (22 water-quality samples, 3 sequentially collected samples, and 3 trip blanks), and 6 samples from water-treatment facilities were collected. Excluding trip blanks, samples from water-treatment facilities, and sequentially collected samples, the pesticides detected in the samples and the percentage of samples in which they were detected, were as follows: atrazine and metolachlor, 86 percent; alachlor, 55 percent; simazine, 45 percent; diazinon, 27 percent; cyanazine and carbaryl, 23 percent; linuron and isophenfos, 9 percent; and chlorpyrifos, 5 percent.Diazinon, detected in one stormflow sample collected from Matchaponix Brook on August 6, 1990, was the only compound to exceed the U.S. Environmental Protection Agency's recommended Lifetime Health Advisory Limit. Correlation between ranked metolachlor concentrations and ranked flow rates was high, and 25 percent of the variance in metolachlor concentrations can be attributed to variations in flow rate. Pesticide residues were detected in samples of pretreated and treated water from water-treatment facilities. Concentrations of all

  19. Spatial dynamics of water management in irrigated agriculture

    NASA Astrophysics Data System (ADS)

    Muralidharan, Daya; Knapp, Keith C.

    2009-05-01

    Irrigated agriculture provides 40% of worldwide food supplies but uses large amounts of scarce freshwater and contributes to environmental degradation. At the very core of this problem lie decisions made by irrigators subject to biophysical relations. This research develops a microeconomic model of irrigation management taking into account the dynamics of plant growth over the season, spatial variability in infiltration of applied irrigation water, and fundamental principles from subsurface hydrology. The analysis shows that spatial variability in water infiltration common to traditional irrigation systems increases both applied irrigation water and deep percolation flows by very substantial amounts compared to uniform infiltration. The analysis demonstrates that efficient irrigation management can significantly reduce both applied water and deep percolation at relatively low costs, at least up to a certain level. A long-run analysis of optimal irrigation systems including capital costs indicates that traditional furrow systems are economically efficient over a wide range of water prices and deep percolation costs. Overall, the results indicate that optimal irrigation management can achieve significant resource conservation and pollution control with low loss in agricultural net benefits and without land retirement, investment in capital-intensive systems, or crop switching.

  20. Agricultural virtual water flows within the United States

    NASA Astrophysics Data System (ADS)

    Dang, Qian; Lin, Xiaowen; Konar, Megan

    2015-02-01

    Trade plays an increasingly important role in the global food system, which is projected to be strained by population growth, economic development, and climate change. For this reason, there has been a surge of interest in the water resources embodied in international trade, referred to as "global virtual water trade." In this paper, we present a comprehensive assessment of virtual water flows within the United States (U.S.), a country with global importance as a major agricultural producer and trade power. This is the first study of domestic virtual water flows based upon intranational food transfer empirical data and it provides insight into how the properties of virtual water transfers vary across scales. We find that the volume of virtual water flows within the U.S. is equivalent to 51% of international flows, which is slightly higher than the U.S. food value and mass shares, due to the fact that water-intensive meat commodities comprise a much larger fraction of food transfers within the U.S.. The U.S. virtual water flow network is more social, homogeneous, and equitable than the global virtual water trade network, although it is still not perfectly equitable. Importantly, a core group of U.S. States is central to the network structure, indicating that both domestic and international trade may be vulnerable to disruptive climate or economic shocks in these U.S. States.

  1. Modeling Halophytic Plants in APEX for Sustainable Water and Agriculture

    NASA Astrophysics Data System (ADS)

    DeRuyter, T.; Saito, L.; Nowak, B.; Rossi, C.; Toderich, K.

    2013-12-01

    A major problem for irrigated agricultural production is soil salinization, which can occur naturally or can be human-induced. Human-induced, or secondary salinization, is particularly a problem in arid and semi-arid regions, especially in irrigated areas. Irrigated land has more than twice the production of rainfed land, and accounts for about one third of the world's food, but nearly 20% of irrigated lands are salt-affected. Many farmers worldwide currently seasonally leach their land to reduce the soil salt content. These practices, however, create further problems such as a raised groundwater table, and salt, fertilizer, and pesticide pollution of nearby lakes and groundwater. In Uzbekistan, a combination of these management practices and a propensity to cultivate 'thirsty' crops such as cotton has also contributed to the Aral Sea shrinking nearly 90% by volume since the 1950s. Most common agricultural crops are glycophytes that have reduced yields when subjected to salt-stress. Some plants, however, are known as halophytic or 'salt-loving' plants and are capable of completing their life-cycle in higher saline soil or water environments. Halophytes may be useful for human consumption, livestock fodder, or biofuel, and may also be able to reduce or maintain salt levels in soil and water. To assess the potential for these halophytes to assist with salinity management, we are developing a model that is capable of tracking salinity under different management practices in agricultural environments. This model is interdisciplinary as it combines fields such as plant ecology, hydrology, and soil science. The US Department of Agriculture (USDA) model, Agricultural Policy/Environmental Extender (APEX), is being augmented with a salinity module that tracks salinity as separate ions across the soil-plant-water interface. The halophytes Atriplex nitens, Climacoptera lanata, and Salicornia europaea are being parameterized and added into the APEX model database. Field sites

  2. Assessment of agricultural return flows under changing climate and crop water management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Water rights, policy and emergent water markets in the semi-arid regions of the western USA, and worldwide, call for improved estimates of agricultural water budgets. Agricultural water is seen as a major potential water supply with high commodity value as municipalities seek water security under g...

  3. Horse paddocks - an emerging source of agricultural water pollution

    NASA Astrophysics Data System (ADS)

    Masud Parvage, Mohammed; Ulén, Barbro; Kirchmann, Holger

    2015-04-01

    Horse farms occupy about 4% of the total agricultural land in the EU but are not well investigated with regard to their impact on water quality. Horse paddocks commonly hold horses on a limited space and the animal density often exceeds the recommended density. Therefore, paddock soils receive significant amounts of phosphorus (P) and nitrogen (N) through feed residues and deposition of faeces and urine, which can lead to nutrient build-up in the soil and subsequent losses to aquatic systems. This study characterized the potential risk of phosphorus (P) and nitrogen (N) leaching losses from Swedish horse paddocks through three stage examination of soil and water P and N status. The experiment began with a pilot study where surface soil P status and eight years of drainage P data were examined from a paddock catchment and an adjacent arable catchment both receiving similar amount of P and N over years. Results showed that there were no signi?cant differences in water-soluble P (WSP) or total P data in soils but the drainage water P concentrations, being higher in the paddock catchment (0.33 mg P l-1, mainly in dissolved reactive form) than the arable catchment (0.10 mg P l-1). In the second experiment, soil P and N status were examined in different parts of horse paddocks (feeding, grazing, and excretion areas) to identify existence of any potential hotspots for losses within the paddock. In total, seven horse farms, covering different grazing densities and soil textures representative of Swedish horse paddocks were examined. The results showed that concentrations of WSP, plant available P or P-AL (P extracted in ammonium acetate lactate solution at pH 3.75), and total N were highest in feeding and excretion areas within the paddocks. It was also observed that the WSP concentration in the paddocks was strongly correlated with horse density (R2 = 0.80, p < 0.001) and P-AL with years of paddock management (R2 = 0.78, p < 0.001). In the final experiment, topsoil

  4. Water and solute balances as a basis for sustainable irrigation agriculture

    NASA Astrophysics Data System (ADS)

    Pla-Sentís, Ildefonso

    2015-04-01

    The growing development of irrigated agriculture is necessary for the sustainable production of the food required by the increasing World's population. Such development is limited by the increasing scarcity and low quality of the available water resources and by the competitive use of the water for other purposes. There are also increasing problems of contamination of surface and ground waters to be used for other purposes by the drainage effluents of irrigated lands. Irrigation and drainage may cause drastic changes in the regime and balance of water and solutes (salts, sodium, contaminants) in the soil profile, resulting in problems of water supply to crops and problems of salinization, sodification and contamination of soils and ground waters. This is affected by climate, crops, soils, ground water depth, irrigation and groundwater composition, and by irrigation and drainage management. In order to predict and prevent such problems for a sustainable irrigated agriculture and increased efficiency in water use, under each particular set of conditions, there have to be considered both the hydrological, physical and chemical processes determining such water and solute balances in the soil profile. In this contribution there are proposed the new versions of two modeling approaches (SOMORE and SALSODIMAR) to predict those balances and to guide irrigation water use and management, integrating the different factors involved in such processes. Examples of their application under Mediterranean and tropical climate conditions are also presented.

  5. Effects of controlled agricultural practices on water quality in the Minnesota sand-plain aquifer

    USGS Publications Warehouse

    Anderson, H.W., Jr.; Stoner, J.D.

    1989-01-01

    Recent studies of Minnesota's sand plains indicate that ground-water chemistry is related to agricultural practices. Surficial sand-plain aquifers cover 8,000,000 acres of Minnesota and are a major source of water for domestic use, irrigation, and some municipal systems. The sand-plain aquifers consist of sand and gravel deposits that are from 20 to greater than 100 feet thick and are covered by a thin sandy loam that generally is less than 2 feet thick. Sand-plain aquifers are recharged by the downward percolation of precipitation through the soil root zone and the unsaturated zone in the sand to the water table. The water table is the upper surface of the zone of saturation and forms the top of the sand-plain aquifer. Sand-plain aquifers are susceptible to contamination by agricultural chemicals (fertilizers and pesticides), if downward-percolating recharge water contains these chemicals. The concentrations of nitrate, pesticides, and some other chemical constituents fluctuate seasonally and differ with depth below the water table (Anderson, 1989). Despite the availability of water-quality data for about 260 wells that were collected during previous studies in three U.S. Geological Survey (USGS) project areas in Minnesota, it is not known how concentrations of agricultural chemicals in ground water relate to the rate and timing of fertilizer and pesticide application or to the tillage practices used. Field-scale research is needed to determine the effects of different farming practices on the concentrations of nitrate, pesticides, and other agricultural chemicals in ground water in the unsaturated and saturated zones.

  6. Dissolved Organic Carbon as a Drinking Water Constituent of Concern in California Agricultural Watersheds

    NASA Astrophysics Data System (ADS)

    Pellerin, B. A.; Bergamaschi, B. A.; Downing, B. D.; Bachand, P. A.; Deverel, S.; Kendall, C.

    2007-12-01

    Dissolved organic carbon (DOC) from the breakdown of plant and animal material is a concern for drinking water quality in California due to the potential formation of carcinogenic byproducts during disinfection. Agricultural DOC loading to surface water is a significant concern, but the sources and reactivity in agricultural runoff remains poorly understood. Here we present data on DOC dynamics in surface water from the Willow Slough watershed, a 425\\- km2 agricultural catchment in the Sacramento Valley, California. Samples collected weekly during 2006 and 2007 were analyzed for DOC concentration, optical properties (UV absorbance and fluorescence), 13C\\- DOC isotopes, and trihalomethane formation potential (a regulated disinfection byproduct formed during chlorination). DOC concentrations at the watershed mouth ranged from 2 to 4 mg/L during winter and spring, with a clear increase in DOC concentrations to more than 7 mg L following the onset of summer irrigation. The 13C\\- DOC values revealed a large range (-19 to -27 ‰), with lowest values during winter baseflow and higher values during summer and winter storms. Spectral slopes also varied seasonally (0.012 to 0.020), with steeper slopes during winter baseflow. Both isotopic and optical data provide evidence for algal\\- derived DOC during the winter baseflow and terrestrial sources during winter storms and summer irrigation. Total THM formation potential was higher in winter than summer, and is strongly correlated to DOC concentrations in surface waters (r2 = 0.87). In contrast to the total THM formation potential, the specific THM formation potential (e.g., total THM normalized to DOC) decreased during the summer irrigation season, suggesting a change in reactivity related to DOC source or degradation. Additional data from plant leachates and ground water will be discussed, as well as the implications of watershed management on DOC dynamics and reactivity in agriculturally-dominated landscapes.

  7. Optional water development strategies for the Yellow River Basin: Balancing agricultural and ecological water demands

    NASA Astrophysics Data System (ADS)

    Cai, Ximing; Rosegrant, Mark W.

    2004-08-01

    The Yellow River Basin is of the utmost importance for China in terms of food production, natural resources management, and socioeconomic development. Water withdrawals for agriculture, industry, and households in the past decade have seriously depleted environmental and ecological water requirements in the basin. This study presents a modeling scenario analysis of some water development strategies to harmonize water withdrawal demand and ecological water demand in the Yellow River Basin through water savings and interbasin water transfers. A global water and food analysis model including the Yellow River Basin as one of the modeling units is applied for the analysis. The model demonstrates that there is little hope of resolving the conflict between agriculture water demand and ecological water demand in the basin if the current water use practices continue. Trade-offs exist between irrigation water use and ecological water use, and these trade-offs will become more intense in future years with population growth, urbanization, and industrial development as well as growing food demand. Scenario analysis in this study concludes that increasing basin water use efficiency to 0.67 first and then supplementary water availability by interbasin water transfer through the South-North Water Transfer Project may provide a solution to water management of the Yellow River Basin in the next 25 years.

  8. Evapotranspiration and surface energy balance across an agricultural-urban landscape gradient in Southern California, USA.

    NASA Astrophysics Data System (ADS)

    Shiflett, S. A.; Anderson, R. G.; Jenerette, D.

    2014-12-01

    Urbanization substantially affects energy, surface and air temperature, and hydrology due to extensive modifications in land surface properties such as vegetation, albedo, thermal capacity and soil moisture. The magnitude and direction of these alterations depends heavily on the type of urbanization that occurs. We investigated energy balance variation in a local network of agricultural and urban ecosystems using the eddy covariance method to better understand how vegetation fraction and degree of urbanization affects energy exchanges between the land surface and the atmosphere. We deployed eddy flux systems within a well-irrigated, agricultural citrus orchard, a moderately developed urban zone with a substantial amount of local vegetative cover, and an intensely developed urban zone with minimal vegetative cover and increased impervious surfaces relative to the other two sites. Latent energy (LE) fluxes in the agricultural area ranged from 7.9 ± 1.4 W m-2 (nighttime) to 168.7 ± 6.2 W m-2 (daytime) compared to 10.2 ± 3.5 W m-2 and 40.6 ± 4.1 W m-2, respectively, for the moderately developed urban area. Sensible energy (H) fluxes ranged from -9.1 ± 1.0 W m-2 (nighttime) to 119 ± 7.0 W m-2 (daytime) in the agricultural area compared to 9.6 ± 2.6 W m-2 and 134 ± 6.0 W m-2, respectively, for the moderately developed urban zone. Daytime LE is reduced with increasing urbanization; however, daily cycles of LE are less recognizable in urban areas compared to distinct daily cycles obtained above a mature citrus crop. In contrast, both daytime and nighttime H increases with increasing degree of urbanization. Reduction in vegetation and increases in impervious surfaces along an urbanization gradient leads to alterations in energy balance, which are associated with microclimate and water use changes.

  9. TECHNICAL CONCEPTS RELATED TO CONSERVATION OF IRRIGATION AND RAIN WATER IN AGRICULTURAL SYSTEMS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Forty percent of freshwater withdrawals in the U.S. are for irrigated agriculture, which contributed 55$ billion to the economy in 2002. Increasing diversions of water for urban, environmental, and other uses will likely decrease water available to agriculture. Agricultural water conservation is tou...

  10. Modeling water outflow from tile-drained agricultural fields.

    PubMed

    Kuzmanovski, Vladimir; Trajanov, Aneta; Leprince, Florence; Džeroski, Sašo; Debeljak, Marko

    2015-02-01

    The estimation of the pollution risk of surface and ground water with plant protection products applied on fields depends highly on the reliable prediction of the water outflows over (surface runoff) and through (discharge through sub-surface drainage systems) the soil. In previous studies, water movement through the soil has been simulated mainly using physically-based models. The most frequently used models for predicting soil water movement are MACRO, HYDRUS-1D/2D and Root Zone Water Quality Model. However, these models are difficult to apply to a small portion of land due to the information required about the soil and climate, which are difficult to obtain for each plot separately. In this paper, we focus on improving the performance and applicability of water outflow modeling by using a modeling approach based on machine learning techniques. It allows us to overcome the major drawbacks of physically-based models e.g., the complexity and difficulty of obtaining the information necessary for the calibration and the validation, by learning models from data collected from experimental fields that are representative for a wider area (region). We evaluate the proposed approach on data obtained from the La Jaillière experimental site, located in Western France. This experimental site represents one of the ten scenarios contained in the MACRO system. Our study focuses on two types of water outflows: discharge through sub-surface drainage systems and surface runoff. The results show that the proposed modeling approach successfully extracts knowledge from the collected data, avoiding the need to provide the information for calibration and validation of physically-based models. In addition, we compare the overall performance of the learned models with the performance of existing models MACRO and RZWQM. The comparison shows overall improvement in the prediction of discharge through sub-surface drainage systems, and partial improvement in the prediction of the surface

  11. Balancing water scarcity and quality for sustainable irrigated agriculture

    NASA Astrophysics Data System (ADS)

    Assouline, Shmuel; Russo, David; Silber, Avner; Or, Dani

    2015-05-01

    The challenge of meeting the projected doubling of global demand for food by 2050 is monumental. It is further exacerbated by the limited prospects for land expansion and rapidly dwindling water resources. A promising strategy for increasing crop yields per unit land requires the expansion of irrigated agriculture and the harnessing of water sources previously considered "marginal" (saline, treated effluent, and desalinated water). Such an expansion, however, must carefully consider potential long-term risks on soil hydroecological functioning. The study provides critical analyses of use of marginal water and management approaches to map out potential risks. Long-term application of treated effluent (TE) for irrigation has shown adverse impacts on soil transport properties, and introduces certain health risks due to the persistent exposure of soil biota to anthropogenic compounds (e.g., promoting antibiotic resistance). The availability of desalinated water (DS) for irrigation expands management options and improves yields while reducing irrigation amounts and salt loading into the soil. Quantitative models are used to delineate trends associated with long-term use of TE and DS considering agricultural, hydrological, and environmental aspects. The primary challenges to the sustainability of agroecosystems lies with the hazards of saline and sodic conditions, and the unintended consequences on soil hydroecological functioning. Multidisciplinary approaches that combine new scientific knowhow with legislative, economic, and societal tools are required to ensure safe and sustainable use of water resources of different qualities. The new scientific knowhow should provide quantitative models for integrating key biophysical processes with ecological interactions at appropriate spatial and temporal scales.

  12. Grass mulching effect on infiltration, surface runoff and soil loss of three agricultural soils in Nigeria.

    PubMed

    Adekalu, K O; Olorunfemi, I A; Osunbitan, J A

    2007-03-01

    Mulching the soil surface with a layer of plant residue is an effective method of conserving water and soil because it reduces surface runoff, increases infiltration of water into the soil and retard soil erosion. The effectiveness of using elephant grass (Pennisetum purpureum) as mulching material was evaluated in the laboratory using a rainfall simulator set at rainfall intensities typical of the tropics. Six soil samples, two from each of the three major soil series representing the main agricultural soils in South Western Nigeria were collected, placed on three different slopes, and mulched with different rates of the grass. The surface runoff, soil loss, and apparent cumulative infiltration were then measured under each condition. The results with elephant grass compared favorably with results from previous experiments using rice straw. Runoff and soil loss decreased with the amount of mulch used and increased with slope. Surface runoff, infiltration and soil loss had high correlations (R = 0.90, 0.89, and 0.86, respectively) with slope and mulch cover using surface response analysis. The mean surface runoff was correlated negatively with sand content, while mean soil loss was correlated positively with colloidal content (clay and organic matter) of the soil. Infiltration was increased and soil loss was reduced greatly with the highest cover. Mulching the soils with elephant grass residue may benefit late cropping (second cropping) by increasing stored soil water for use during dry weather and help to reduce erosion on sloping land. PMID:16678407

  13. Hydrogeology and potential effects of changes in water use, Carson Desert agricultural area, Churchill County, Nevada

    USGS Publications Warehouse

    Maurer, Douglas K.; Johnson, Ann K.; Welch, Alan H.

    1996-01-01

    Operating Criteria and Procedures for Newlands Project irrigation and Public Law 101-618 could result in reductions in surface water used for agriculture in the Carson Desert, potentially affecting ground-water supplies from shallow, intermediate, and basalt aquifers. A near-surface zone could exist at the top of the shallow aquifer near the center and eastern parts of the basin where underlying clay beds inhibit vertical flow and could limit the effects of changes in water use. In the basalt aquifer, water levels have declined about 10 feet from pre-pumping levels, and chloride and arsenic concentrations have increased. Conceptual models of the basin suggest that changes in water use in the western part of the basin would probably affect recharge to the shallow, intermediate, and basalt aquifers. Lining canals and removing land from production could cause water-level declines greater than 10 feet in the shallow aquifer up to 2 miles from lined canals. Removing land from production could cause water levels to decline from 4 to 17 feet, depending on the distribution of specific yield in the basin and the amount of water presently applied to irrigated fields. Where wells pump from a near-surface zone of the shallow aquifer, water level declines might not greatly affect pumping wells where the thickness of the zone is greatest, but could cause wells to go dry where the zone is thin.

  14. Water Resources and Agricultural Water Use in the North China Plain: Current Status and Management Options

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Serious water deficits with deteriorating environmental quality are threatening agricultural sustainability in the North China Plain (NCP). This paper addresses spatial and temporal availability of water resources in the NCP, and identifies the effects of soil management, irrigation and crop genetic...

  15. Water Quality Benefits of Constructed Wetlands Integrated Within Agricultural Water Recycling Systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Constructed wetlands have been integrated within innovative agricultural water recycling systems, and these systems are now being evaluated at three demonstration sites located in the northwest Ohio portion of the Maumee River Basin (Defiance, Fulton, and Van Wert Counties). The water recycling syst...

  16. Temporal stability of soil water content and soil water flux patterns across agricultural fields

    Technology Transfer Automated Retrieval System (TEKTRAN)

    When an agricultural field is repeatedly surveyed for soil water content, sites often can be spotted where soil is consistently wetter or consistently dryer than average across the study area. Temporal stability presents significant interest for upscaling observed soil water content, improving soil ...

  17. GlobWat - a global water balance model to assess water use in irrigated agriculture

    NASA Astrophysics Data System (ADS)

    Hoogeveen, J.; Faurès, J.-M.; Peiser, L.; Burke, J.; van de Giesen, N.

    2015-09-01

    GlobWat is a freely distributed, global soil water balance model that is used by the Food and Agriculture Organization (FAO) to assess water use in irrigated agriculture, the main factor behind scarcity of freshwater in an increasing number of regions. The model is based on spatially distributed high-resolution data sets that are consistent at global level and calibrated against values for internal renewable water resources, as published in AQUASTAT, the FAO's global information system on water and agriculture. Validation of the model is done against mean annual river basin outflows. The water balance is calculated in two steps: first a "vertical" water balance is calculated that includes evaporation from in situ rainfall ("green" water) and incremental evaporation from irrigated crops. In a second stage, a "horizontal" water balance is calculated to determine discharges from river (sub-)basins, taking into account incremental evaporation from irrigation, open water and wetlands ("blue" water). The paper describes the methodology, input and output data, calibration and validation of the model. The model results are finally compared with other global water balance models to assess levels of accuracy and validity.

  18. Water resource management for sustainable agriculture in Punjab, India.

    PubMed

    Aggarwal, Rajan; Kaushal, Mohinder; Kaur, Samanpreet; Farmaha, Bhupinder

    2009-01-01

    The state of Punjab comprising 1.5% area of the country has been contributing 40-50% rice and 60-65% wheat to the central pool since last three decades. During last 35 years The area under foodgrains has increased from 39,200 sq km ha to 63,400 sq km and the production of rice and wheat has increased from 0.18 to 0.32 kg/m2 and 0.22 to 0.43 kg/m2 respectively. This change in cropping pattern has increased irrigation water requirement tremendously and the irrigated area has increased from 71 to 95% in the state. Also the number of tube wells has increased from 0.192 to 1.165 million in the last 35 years. The excessive indiscriminate exploitation of ground water has created a declining water table situation in the state. The problem is most critical in central Punjab. The average rate of decline over the last few years has been 55 cm per year. The worst affected districts are Moga, Sangrur, Nawanshahar, Ludhiana and Jalandhar. This has resulted in extra power consumption, affects the socio-economic conditions of the small farmers, destroy the ecological balance and adversely affect the sustainable agricultural production and economy of the state. Therefore, in this paper attempt has been made to analyse the problem of declining water table, possible factors responsible for this and suggest suitable strategies for arresting declining water table for sustainable agriculture in Punjab. The strategies include shift of cropping pattern, delay in paddy transplantation, precision irrigation and rainwater harvesting for artificial groundwater recharge. PMID:19934512

  19. Modelling mitigation options to reduce diffuse nitrogen water pollution from agriculture.

    PubMed

    Bouraoui, Fayçal; Grizzetti, Bruna

    2014-01-15

    Agriculture is responsible for large scale water quality degradation and is estimated to contribute around 55% of the nitrogen entering the European Seas. The key policy instrument for protecting inland, transitional and coastal water resources is the Water Framework Directive (WFD). Reducing nutrient losses from agriculture is crucial to the successful implementation of the WFD. There are several mitigation measures that can be implemented to reduce nitrogen losses from agricultural areas to surface and ground waters. For the selection of appropriate measures, models are useful for quantifying the expected impacts and the associated costs. In this article we review some of the models used in Europe to assess the effectiveness of nitrogen mitigation measures, ranging from fertilizer management to the construction of riparian areas and wetlands. We highlight how the complexity of models is correlated with the type of scenarios that can be tested, with conceptual models mostly used to evaluate the impact of reduced fertilizer application, and the physically-based models used to evaluate the timing and location of mitigation options and the response times. We underline the importance of considering the lag time between the implementation of measures and effects on water quality. Models can be effective tools for targeting mitigation measures (identifying critical areas and timing), for evaluating their cost effectiveness, for taking into consideration pollution swapping and considering potential trade-offs in contrasting environmental objectives. Models are also useful for involving stakeholders during the development of catchments mitigation plans, increasing their acceptability. PMID:23998504

  20. Sustainability of Italian Agriculture: A Methodological Approach for Assessing Crop Water Footprint at Local Scale

    NASA Astrophysics Data System (ADS)

    Altobelli, F.; Dalla Marta, A.; Cimino, O.; Orlandini, S.; Natali, F.

    2014-12-01

    In a world where population is rapidly growing and where several planetary boundaries (i.e. climate change, biodiversity loss and nitrogen cycle) have already been crossed, agriculture is called to respond to the needs of food security through a sustainable use of natural resources. In particular, water is one of the main elements of fertility so the agricultural activity, and the whole agro-food chain, is one of the productive sectors more dependent on water resource and it is able to affect, at regional level, its availability for all the other sectors. In this study, we proposed a methodology for assessing the green and blue water footprint of the main Italian crops typical of the different geographical areas (northwest, northeast, center, and south) based on data extracted from Italian Farm Accountancy Data Network (FADN). FADN is an instrument for evaluating the income of agricultural holdings and the impacts of the Common Agricultural Policy. Crops were selected based on incidence of cultivated area on the total arable land of FADN farms net. Among others, the database contains data on irrigation management (irrigated surface, length of irrigation season, volumes of water, etc.), and crop production. Meteorological data series were obtained by a combination of local weather stations and ECAD E-obs spatialized database. Crop water footprints were evaluated against water availability and risk of desertification maps of Italy. Further, we compared the crop water footprints obtained with our methodology with already existing data from similar studies in order to highlight the effects of spatial scale and level of detail of available data.

  1. Evaluation of nitrate removal in buffer zone supply by water from agricultural drained catchment

    NASA Astrophysics Data System (ADS)

    Fesneau, Corinne; Tournebize, Julien; Chaumont, Cedric; Guenne, Angeline

    2010-05-01

    The European Directive 2000/60/CE states objectives of a good ecological and chemical status from water body until 2015. The Cemagref project focuses on the constructed wetlands (CW) which can be used as buffer zones to lower the impact of agricultural practices on hydrosystems and decrease or even stop the transfer of contaminants via the surface waters. The experiments are carried out on a drained area where the runoff is limited and waters from the soil profile are concentrated at the drain pipes outlet. The constructed wetland studied is located at Aulnoy (77) at 70 km north-east of Paris, within the Orgeval catchment (France). Our aim is to assess the efficiency of constructed wetlands on the removal of agricultural nitrates. We are also interested in the hydrological balance of CW and agricultural catchment. The buffer zone is connected to a drained agricultural catchment of 35 hectares. The crops in the agricultural plots mainly consist in cereals (corn, maize), vegetables (horse bean, pea), sugar beet and rape. Nitrogen fertilizers are applied following normal agricultural practices. The site is monitored since 2005 for discharge and nitrate concentration in order to infer water and nitrate budgets. The buffer zone includes a pond (860m2) and a reservoir (3305 m2). The storage volume is estimated to 8000m3 which corresponds to about 10% of drainage runoff. Our study reveals potential nitrate removal because a decrease of nitrate average contents has been documented between inlet and outlet CW over a measurement period of 4 years. Average values of 57 mg/l, 40 mg/l and 27 mg/l are respectively measured at the main drain, in the pond mean and in the reservoir; that is a reduction close to 50% of nitrate fluxes. The semi-potential denitrification experiments confirm the denitrification capacity of buffer zone sediments. This constructed wetland allows the treatment of waters from agricultural drainage and provides results in line with the expectations of "good

  2. Water molecules orientation in surface layer

    NASA Astrophysics Data System (ADS)

    Klingo, V. V.

    2000-08-01

    The water molecules orientation has been investigated theoretically in the water surface layer. The surface molecule orientation is determined by the direction of a molecule dipole moment in relation to outward normal to the water surface. Entropy expressions of the superficial molecules in statistical meaning and from thermodynamical approach to a liquid surface tension have been found. The molecules share directed opposite to the outward normal that is hydrogen protons inside is equal 51.6%. 48.4% water molecules are directed along to surface outward normal that is by oxygen inside. A potential jump at the water surface layer amounts about 0.2 volts.

  3. Improvements in agricultural water decision support using remote sensing

    NASA Astrophysics Data System (ADS)

    Marshall, M. T.

    2012-12-01

    Population driven water scarcity, aggravated by climate-driven evaporative demand in dry regions of the world, has the potential of transforming ecological and social systems to the point of armed conflict. Water shortages will be most severe in agricultural areas, as the priority shifts to urban and industrial use. In order to design, evaluate, and monitor appropriate mitigation strategies, predictive models must be developed that quantify exposure to water shortage. Remote sensing data has been used for more than three decades now to parametrize these models, because field measurements are costly and difficult in remote regions of the world. In the past decade, decision-makers for the first time can make accurate and near real-time evaluations of field conditions with the advent of hyper- spatial and spectral and coarse resolution continuous remote sensing data. Here, we summarize two projects representing diverse applications of remote sensing to improve agricultural water decision support. The first project employs MODIS (coarse resolution continuous data) to drive an evapotranspiration index, which is combined with the Standardized Precipitation Index driven by meteorological satellite data to improve famine early warning in Africa. The combined index is evaluated using district-level crop yield data from Kenya and Malawi and national-level crop yield data from the United Nations Food and Agriculture Organization. The second project utilizes hyper- spatial (GeoEye 1, Quickbird, IKONOS, and RapidEye) and spectral (Hyperion/ALI), as well as multi-spectral (Landsat ETM+, SPOT, and MODIS) data to develop biomass estimates for key crops (alfalfa, corn, cotton, and rice) in the Central Valley of California. Crop biomass is an important indicator of crop water productivity. The remote sensing data is combined using various data fusion techniques and evaluated with field data collected in the summer of 2012. We conclude with a brief discussion on implementation of

  4. Assessment of Crop Water Requirement Methods for Annual Agricultural Water Allocation Planning

    NASA Astrophysics Data System (ADS)

    Aghdasi, F.; Sharifi, M. A.; van der Tol, C.

    2010-05-01

    The potential use of remote sensing in water resource and in particular in irrigation management has been widely acknowledged. However, in reality, operational applications of remote sensing in irrigation management are few. In this study, the applicability of the main available remote sensing based techniques of irrigation management is evaluated in a pilot area in Iran. The evaluated techniques include so called Crop Water Requirement "CWR" methods for the planning of annual water allocation in irrigated agriculture. A total of 40 years of historical weather data were classified into wet, normal, and dry years using a Standardised Precipitation Index (SPI). For each of these three classes the average CWR was calculated. Next, by applying Markov Chain Process to the time series of precipitation, the expected CWR for the forthcoming planning year was estimated. Using proper interpolation techniques the expected CWR at each station was converted to CWR map of the area, which was then used for annual water allocation planning. To estimate the crop water requirement, methods developed for the DEMETER project (DEMonstration of Earth observation Technologies in Routine irrigation advisory services) and Surface Energy Balance System "SEBS" algorithm were used, and their results were compared with conventional methods, including FAO-56 and lysimeter data amongst others. Use was made of both ASTER and MODIS images to determine crop water requirement at local and regional scales. Four methods of estimating crop coefficients were used: DEMETER Kc-NDVI, DEMETER Kc-analytical, FAO-56 and SEBS algorithm. Results showed that DEMETER (analytical approach) and FAO methods with lowest RMSE are more suitable methods for determination of crop coefficient than SEBS, which gives actual rather than potential evapotranspiration. The use of ASTER and MODIS images did not result in significantly different crop coefficients in the pilot area for the DEMETER analytical approach (α=0

  5. Characterisation of areas under irrigated agriculture: mapping and water use

    NASA Astrophysics Data System (ADS)

    Peña Arancibia, Jorge; McVicar, Tim R.; Guerschman, Juan P.; Li, Lingtao T.

    2014-05-01

    The evolution of remote sensing and classification methods has enabled effective mapping, monitoring and management of irrigated agriculture. A random forest classification was implemented using learning samples inferred from Landsat TM/ETM data and monthly time-series of remotely-sensed observations from the MODerate resolution Imaging Spectroradiometer (MODIS). The covariates included in the method characterised: (i) the vegetation phenology via the recurrent and persistent fractions of photosynthetically active radiation (fPARrecandfPARper, respectively); (ii) vegetation water use via estimates of actual evapotranspiration (AET), rainfall (P) and the difference between AET and P . Maps of irrigated areas under different climates and cropping conditions were produced for the whole Murray-Darling Basin (Australia) for the years 2004 to 2010 with 0.96 observed agreement in terms of the Kappa Index (were a value of 1 indicates perfect agreement). An independent comparison of yearly irrigated area estimates and corresponding water use showed a linear relationship with good agreement (R2 >0.7) against available yearly metered water withdrawals and estimates of agricultural yields. A sequential covariate optimisation suggested that the most important predictors included the emergence-senescence period (as determined by the fPARrec and corresponding rates of change) and the AET surplus over P during this period. The latter can be important when determining more opportunistic irrigation practices due to unreliable water supply in areas with otherwise high annual rainfall. The procedure can be implemented to map irrigated areas at the global scale: the MODIS time-series used in the classification methodology are available globally since February 2000 and so are the Landsat archives which can be used to infer learning samples and irrigation practices elsewhere.

  6. Hydroeconomic optimization of integrated water management and transfers under stochastic surface water supply

    NASA Astrophysics Data System (ADS)

    Zhu, Tingju; Marques, Guilherme Fernandes; Lund, Jay R.

    2015-05-01

    Efficient reallocation and conjunctive operation of existing water supplies is gaining importance as demands grow, competitions among users intensify, and new supplies become more costly. This paper analyzes the roles and benefits of conjunctive use of surface water and groundwater and market-based water transfers in an integrated regional water system where agricultural and urban water users coordinate supply and demand management based on supply reliability and economic values of water. Agricultural users optimize land and water use for annual and perennial crops to maximize farm income, while urban users choose short-term and long-term water conservation actions to maintain reliability and minimize costs. The temporal order of these decisions is represented in a two-stage optimization that maximizes the net expected benefits of crop production, urban conservation and water management including conjunctive use and water transfers. Long-term decisions are in the first stage and short-term decisions are in a second stage based on probabilities of water availability events. Analytical and numerical analyses are made. Results show that conjunctive use and water transfers can substantially stabilize farmer's income and reduce system costs by reducing expensive urban water conservation or construction. Water transfers can equalize marginal values of water across users, while conjunctive use minimizes water marginal value differences in time. Model results are useful for exploring the integration of different water demands and supplies through water transfers, conjunctive use, and conservation, providing valuable insights for improving system management.

  7. Partitioning of Evapotranspiration Using a Stable Water Isotope Technique in a High Temperature Agricultural Production System

    NASA Astrophysics Data System (ADS)

    Lu, X.; Liang, L.; Wang, L.; Jenerette, D.; Grantz, D. A.

    2015-12-01

    Agricultural production in the hot and arid low desert systems of southern California relies heavily on irrigation. A better understanding of how much and to what extent the irrigation water is transpired by crops relative to being lost through evaporation will contribute to better management of increasingly limited agricultural water resources. In this study, we examined the evapotranspiration (ET) partitioning over a field of forage sorghum (S. bicolor) during a growing season with several irrigation cycles. In several field campaigns we used continuous measurements of near-surface variations in the stable isotopic composition of water vapor (δ2H). We employed custom built transparent chambers coupled with a laser-based isotope analyzer and used Keeling plot and mass balance methods for surface flux partitioning. The preliminary results show that δT is more enriched than δE in the early growing season, and becomes less enriched than δE later in the season as canopy cover increases. There is an increase in the contribution of transpiration to ET as (1) leaf area index increases, and (2) as soil surface moisture declines. These results are consistent with theory, and extend these measurements to an environment that experiences extreme soil surface temperatures. The data further support the use of chamber based methods with stable isotopic analysis for characterization of ET partitioning in challenging field environments.

  8. Interactions between ground water and surface water in the Suwannee River basin, Florida

    USGS Publications Warehouse

    Katz, B.G.; DeHan, R.S.; Hirten, J.J.; Catches, J.S.

    1997-01-01

    Ground water and surface water constitute a single dynamic system in roost parts of the Suwannee River basin due to the presence of karat features that facilitate the interaction between the surface and subsurface. Low radon-222 concentrations (below background levels) and enriched amounts of oxygen-18 and deuterium in ground water indicate mixing with surface water in parts of the basin. Comparison of surface water and regional ground water flow patterns indicate that boundaries for ground water basins typically do not coincide with surface water drainage subbasins. There are several areas in the basin where ground water flow that originates outside of the Suwannee River basin crosses surface water basin boundaries during both low-flow and high-flow conditions. In a study area adjacent to the Suwannee River that consists predominantly of agricultural land use, 18 wells tapping the Upper Floridan aquifer and 7 springs were sampled three times during 1990 through 1994 for major dissolved inorganic constituents, trace elements, and nutrients. During a period of above normal rainfall that resulted in high river stage and high ground water levels in 1991, the combination of increased amounts of dissolved organic carbon and decreased levels of dissolved oxygen in ground water created conditions favorable for the natural reduction of nitrate by denitrification reactions in the aquifer. As a result, less nitrate was discharged by ground water to the Suwannee River.

  9. Muddy Water and American Agriculture: How to Best Control Sedimentation From Agricultural Land?

    NASA Astrophysics Data System (ADS)

    Lovejoy, Stephen B.; Lee, John Gary; Beasley, David B.

    1985-08-01

    The role of agricultural sediment in water quality is well documented. While numerous policies have been advocated and initiated, it still appears to be a significant problem. The present analysis concentrates on the outcome of several policy alternatives in terms of sediment delivery and project costs. These results are obtained by combining social science investigation of probable farmer behavior under a variety of scenarios with a hydrologic simulation model which predicts the sediment delivery with different land uses. This integration of social science behavioral research with the hydrologic response simulation model provides a framework to assess the environmental effectiveness of alternative policies aimed at reducing sedimentation. While the results presented here are preliminary, this approach seems to offer great promise as a tool for federal, state and local conservation agencies in their efforts to efficiently and effectively use their limited resources to reduce soil loss.

  10. Multistate Evaluation of Microbial Water and Sediment Quality from Agricultural Recovery Basins.

    PubMed

    Partyka, Melissa L; Bond, Ronald F; Chase, Jennifer A; Kiger, Luana; Atwill, Edward R

    2016-03-01

    Agricultural recovery basins are an important conservation practice designed to provide temporary storage of sediment and water on farms before low-volume discharge. However, food safety concerns have been raised regarding redistribution of captured sediment and water to fields used for human food production. The purpose of this study was to examine the potential microbiological risk that recovery basins may contribute to nearby produce fields and to evaluate characteristics that may influence or mitigate those risks. Water and sediment samples were collected from participating farms in three states and evaluated for bacterial indicators and pathogens over several months. Overall, 45% ( = 48) of water samples and less than 15% ( = 13) of sediment samples were positive for spp. In water samples, the occurrence of was positively associated with the use of surface water as a source of irrigation compared with groundwater as well as log-scale increases in concentration. In sediment samples, was associated with basin location (region) and basin fill levels. Sediment exposed to drying during dewatering had lower concentrations of indicator and a lower proportion of positives than submerged sediment from the same pond. Surrounding landscape characteristics, including vegetative coverage, proximity to livestock operations, and evidence of wildlife, were not correlated with pathogen occurrence in either sediment or water samples, suggesting that although habitat surrounding ponds may be an attractant to wildlife, those features may not contribute to increased pathogen occurrence in agricultural recovery basins. PMID:27065413

  11. Fresh water production from municipal waste water with RO membrane technology and its application for agriculture and industry in arid area

    NASA Astrophysics Data System (ADS)

    Yokoyama, F.

    2015-04-01

    One of the biggest problems of the 21st century is the global water shortage. Therefore it is difficult to increase the quantity of conventional water resources such as surface water and groundwater for agriculture and industry in arid area. Technical advancement in water treatment membrane technology including RO membrane has been remarkable especially in recent years. As the pore size of RO membrane is less than one nanometer, it is possible to produce the fresh water, which satisfies the drinking water quality standards, with utilizing RO membrane. In this report a new fresh water resource from municipal waste water is studied to apply to the plant factory which is the water saving type agriculture and industry in arid area.

  12. Network for Monitoring Agricultural Water Quantity and Water Quality in Arkansas

    NASA Astrophysics Data System (ADS)

    Reba, M. L.; Daniels, M.; Chen, Y.; Sharpley, A.; Teague, T. G.; Bouldin, J.

    2012-12-01

    A network of agricultural monitoring sites was established in 2010 in Arkansas. The state of Arkansas produces the most rice of any state in the US, the 3rd most cotton and the 3rd most broilers. By 2050, agriculture will be asked to produce food, feed, and fiber for the increasing world population. Arkansas agriculture is challenged with reduced water availability from groundwater decline and the associated increase in pumping costs. Excess nutrients, associated in part to agriculture, influence the hypoxic condition in the Gulf of Mexico. All sites in the network are located at the edge-of-field in an effort to relate management to water quantity and water quality. The objective of the network is to collect scientifically sound data at field scales under typical and innovative management for the region. Innovative management for the network includes, but is not limited to, variable rate fertilizer, cover crops, buffer strips, irrigation water management, irrigation planning, pumping plant monitoring and seasonal shallow water storage. Data collection at the sites includes quantifying water inputs and losses, and water quality. Measured water quality parameters include sediment and dissolved nitrate, nitrite and orthophosphate. The measurements at the edge-of-field will be incorporated into the monitoring of field ditches and larger drainage systems to result in a 3-tiered monitoring effort. Partners in the creation of this network include USDA-ARS, Arkansas State University, University of Arkansas, University of Arkansas at Pine Bluff, USDA-NRCS and agricultural producers representing the major commodities of the state of Arkansas. The network is described in detail with preliminary results presented.

  13. Climate change mitigation for agriculture: water quality benefits and costs.

    PubMed

    Wilcock, Robert; Elliott, Sandy; Hudson, Neale; Parkyn, Stephanie; Quinn, John

    2008-01-01

    New Zealand is unique in that half of its national greenhouse gas (GHG) inventory derives from agriculture--predominantly as methane (CH4) and nitrous oxide (N2O), in a 2:1 ratio. The remaining GHG emissions predominantly comprise carbon dioxide (CO2) deriving from energy and industry sources. Proposed strategies to mitigate emissions of CH4 and N2O from pastoral agriculture in New Zealand are: (1) utilising extensive and riparian afforestation of pasture to achieve CO2 uptake (carbon sequestration); (2) management of nitrogen through budgeting and/or the use of nitrification inhibitors, and minimizing soil anoxia to reduce N2O emissions; and (3) utilisation of alternative waste treatment technologies to minimise emissions of CH4. These mitigation measures have associated co-benefits and co-costs (disadvantages) for rivers, streams and lakes because they affect land use, runoff loads, and receiving water and habitat quality. Extensive afforestation results in lower specific yields (exports) of nitrogen (N), phosphorus (P), suspended sediment (SS) and faecal matter and also has benefits for stream habitat quality by improving stream temperature, dissolved oxygen and pH regimes through greater shading, and the supply of woody debris and terrestrial food resources. Riparian afforestation does not achieve the same reductions in exports as extensive afforestation but can achieve reductions in concentrations of N, P, SS and faecal organisms. Extensive afforestation of pasture leads to reduced water yields and stream flows. Both afforestation measures produce intermittent disturbances to waterways during forestry operations (logging and thinning), resulting in sediment release from channel re-stabilisation and localised flooding, including formation of debris dams at culverts. Soil and fertiliser management benefits aquatic ecosystems by reducing N exports but the use of nitrification inhibitors, viz. dicyandiamide (DCD), to achieve this may under some circumstances

  14. Modeling the impacts of climate change and agricultural management practices on surface erosion in a dryland agricultural basin

    NASA Astrophysics Data System (ADS)

    Ottenbreit, E.; Adam, J. C.; Barber, M. E.

    2010-12-01

    The objective of this study is to investigate the effects of climate change and agricultural management practices on suspended sediment concentrations in the Potlach River basin in northwestern Idaho. Suspended sediment is a pollutant in many water systems and contributes to the impairment of streams. Conventional tillage practices and rain-on-snow events in the Palouse region of northern Idaho and eastern Washington can produce some of the highest sediment losses per acre in the United States. Climate change may lead to further problems as more frequent and intense winter storm events are predicted to occur. Many hydrological models have been developed which examine suspended sediment in river systems. The Potlatch River basin near Julietta, ID was examined using the Distributed Hydrology Soil Vegetation Model (DHSVM), which has a sediment module that includes surface erosion and channel sediment transport. DHSVM was calibrated and evaluated over the historical period of streamflow observations and was used to predict soil erosion rates and suspended sediment concentrations using a range of downscaled Global Climate Models (GCMs) emissions scenarios for the year 2045. Furthermore, the sensitivity of suspended sediment concentrations to conventional versus convservative tillage practices was explored. The results show that as the projected climate-driven intensity of storms increase, more sediment is predicted in the Potlatch River. Suspended sediment and streamflow are predicted to increase during the late fall through the early spring. This increase occurs during times of heightened runoff when suspended sediment concentration in the river is highest. Three tillage scenarios were incorporated into DHSVM for winter wheat: conventional till, reduced till, and no till. Erosion and suspended sediment were higher during storm events under conventional agricultural tillage scenarios. In the long-term, this research can lead to examination of the effects of climate

  15. Water demand and supply co-adaptation to mitigate climate change impacts in agricultural water management

    NASA Astrophysics Data System (ADS)

    Giuliani, Matteo; Mainardi, Matteo; Castelletti, Andrea; Gandolfi, Claudio

    2013-04-01

    Agriculture is the main land use in the world and represents also the sector characterised by the highest water demand. To meet projected growth in human population and per-capita food demand, agricultural production will have to significantly increase in the next decades. Moreover, water availability is nowadays a limiting factor for agricultural production, and is expected to decrease over the next century due to climate change impacts. To effectively face a changing climate, agricultural systems have therefore to adapt their strategies (e.g., changing crops, shifting sowing and harvesting dates, adopting high efficiency irrigation techniques). Yet, farmer adaptation is only one part of the equation because changes in water supply management strategies, as a response to climate change, might impact on farmers' decisions as well. Despite the strong connections between water demand and supply, being the former dependent on agricultural practices, which are affected by the water available that depends on the water supply strategies designed according to a forecasted demand, an analysis of their reciprocal feedbacks is still missing. Most of the recent studies has indeed considered the two problems separately, either analysing the impact of climate change on farmers' decisions for a given water supply scenario or optimising water supply for different water demand scenarios. In this work, we explicitly connect the two systems (demand and supply) by activating an information loop between farmers and water managers, to integrate the two problems and study the co-evolution and co-adaptation of water demand and water supply systems under climate change. The proposed approach is tested on a real-world case study, namely the Lake Como serving the Muzza-Bassa Lodigiana irrigation district (Italy). In particular, given an expectation of water availability, the farmers are able to solve a yearly planning problem to decide the most profitable crop to plant. Knowing the farmers

  16. Wave Turbulence on Water Surface

    NASA Astrophysics Data System (ADS)

    Nazarenko, Sergey; Lukaschuk, Sergei

    2016-03-01

    We overview the wave turbulence approach by example of one physical system: gravity waves on the surface of an infinitely deep fluid. In the theoretical part of our review, we derive the nonlinear Hamiltonian equations governing the water-wave system and describe the premises of the weak wave turbulence theory. We outline derivation of the wave-kinetic equation and the equation for the probability density function, and most important solutions to these equations, including the Kolmogorov-Zakharov spectra corresponding to a direct and an inverse turbulent cascades, as well as solutions for non-Gaussian wave fields corresponding to intermittency. We also discuss strong wave turbulence as well as coherent structures and their interaction with random waves. We describe numerical and laboratory experiments, and field observations of gravity wave turbulence, and compare their results with theoretical predictions.

  17. Surface water discharges from onshore stripper wells.

    SciTech Connect

    Veil, J. A.

    1998-01-16

    Under current US Environmental Protection Agency (EPA) rules, small onshore oil producers are allowed to discharge produced water to surface waters with approval from state agencies; but small onshore gas producers, however, are prohibited from discharging produced water to surface waters. The purpose of this report is to identify those states that allow surface water discharges from small onshore oil operations and to summarize the types of permitting controls they use. It is intended that the findings of this report will serve as a rationale to encourage the EPA to revise its rules and to remove the prohibition on surface water discharges from small gas operations.

  18. Patterns and controls of nitrous oxide emissions from waters draining a subtropical agricultural valley

    NASA Astrophysics Data System (ADS)

    Harrison, John; Matson, Pamela

    2003-09-01

    Although nitrous oxide (N2O) emission from agricultural runoff is thought to constitute a globally important source of this greenhouse gas, N2O flux from polluted aquatic systems is poorly understood and scarcely reported, especially in low-latitude (0°-30°) regions where rapid agricultural intensification is occurring. We measured N2O emissions, dissolved N2O concentrations, and factors likely to control rates of N2O production in drainage canals receiving agricultural and mixed agricultural/urban inputs from the intensively farmed Yaqui Valley of Sonora, Mexico. Average per-area N2O flux in both purely agricultural and mixed urban/agricultural drainage systems (16.5 ng N2O-N cm-2 hr-1) was high compared to other fresh water fluxes, and extreme values ranged up to 244.6 ng N2O-N cm-2 hr-1. These extremely high N2O fluxes occurred during green algae blooms, when organic carbon, nitrogen, and oxygen concentrations were high, and only in canals receiving pig-farm and urban inputs, suggesting an important link between land-use and N2O emissions. N2O concentrations and fluxes correlated significantly with water column concentrations of nitrate, particulate organic carbon and nitrogen, ammonium, and chlorophyll a, and a multiple linear regression model including ammonium, dissolved organic carbon, and particulate organic carbon was the best predictor of [N2O] (r2 = 52%). Despite high per-area N2O fluxes, our estimate of regional N2O emission from surface drainage (20,869 kg N2O-N yr-1; 0.046% of N-fertilizer inputs) was low compared to values predicted by algorithms used in global budgets.

  19. Overview of advances in water management in agricultural production:Sensor based irrigation management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Technological advances in irrigated agriculture are crucial to meeting the challenge of increasing demand for agricultural products given limited quality and quantity of water resources for irrigation, impacts of climate variability, and the need to reduce environmental impacts. Multidisciplinary ap...

  20. Modelling Approach to Assess Future Agricultural Water Demand

    NASA Astrophysics Data System (ADS)

    Spano, D.; Mancosu, N.; Orang, M.; Sarreshteh, S.; Snyder, R. L.

    2013-12-01

    The combination of long-term climate changes (e.g., warmer average temperatures) and extremes events (e.g., droughts) can have decisive impacts on water demand, with further implications on the ecosystems. In countries already affected by water scarcity, water management problems are becoming increasingly serious. The sustainable management of available water resources at the global, regional, and site-specific level is necessary. In agriculture, the first step is to compute how much water is needed by crops in regards to climate conditions. Modelling approach can be a way to compute crop water requirement (CWR). In this study, the improved version of the SIMETAW model was used. The model is a user friendly soil water balance model, developed by the University of California, Davis, the California Department of Water Resource, and the University of Sassari. The SIMETAW# model assesses CWR and generates hypothetical irrigation scheduling for a wide range of irrigated crops experiencing full, deficit, or no irrigation. The model computes the evapotranspiration of the applied water (ETaw), which is the sum of the net amount of irrigation water needed to match losses due to the crop evapotranspiration (ETc). ETaw is determined by first computing reference evapotranspiration (ETo) using the daily standardized Reference Evapotranspiration equation. ETaw is computed as ETaw = CETc - CEr, where CETc and CE are the cumulative total crop ET and effective rainfall values, respectively. Crop evapotranspiration is estimated as ETc = ETo x Kc, where Kc is the corrected midseason tabular crop coefficient, adjusted for climate conditions. The net irrigation amounts are determined from a daily soil water balance, using an integrated approach that considers soil and crop management information, and the daily ETc estimates. Using input information on irrigation system distribution uniformity and runoff, when appropriate, the model estimates the applied water to the low quarter of the

  1. GlobWat - a global water balance model to assess water use in irrigated agriculture

    NASA Astrophysics Data System (ADS)

    Hoogeveen, J.; Faurès, J.-M.; Peiser, L.; Burke, J.; van de Giesen, N.

    2015-01-01

    GlobWat is a freely distributed, global soil water balance model that is used by FAO to assess water use in irrigated agriculture; the main factor behind scarcity of freshwater in an increasing number of regions. The model is based on spatially distributed high resolution datasets that are consistent at global level and calibrated against values for Internal Renewable Water Resources, as published in AQUASTAT, FAO's global information system on water and agriculture. Validation of the model is done against mean annual river basin outflows. The water balance is calculated in two steps: first a "vertical" water balance is calculated that includes evaporation from in situ rainfall ("green" water) and incremental evaporation from irrigated crops. In a second stage, a "horizontal" water balance is calculated to determine discharges from river (sub-)basins, taking into account incremental evaporation from irrigation, open water and wetlands ("blue" water). The paper describes methodology, input and output data, calibration and validation of the model. The model results are finally compared with other global water balance models.

  2. Occurrence of pesticides and contaminants of emerging concern in surface waters: Influence of surrounding land use and evaluation of sampling methods

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Biologically active compounds originating from agricultural, residential, and industrial sources have been detected in surface waters, which have invoked concern of their potential ecological and human health effects. Automated and grab surface water samples, passive water samples - Polar Organic Co...

  3. Agricultural Drainage Water Management in the Upper Mississippi River Basin: Potential Impact and Implementation Strategies

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The unique soil and climate of the Upper Mississippi River Basin area provide the resources for bountiful agricultural production. Agricultural drainage (both surface and subsurface drainage) is essential for achieving economically viable crop production and management. Drainage practices alter the ...

  4. The central role of agricultural water-use productivity in sustainable water management (Invited)

    NASA Astrophysics Data System (ADS)

    Gleick, P. H.

    2013-12-01

    As global and regional populations continue to rise for the next several decades, the need to grow more food will worsen old -- and produce new -- challenges for water resources. Expansion of irrigated agriculture is slowing due to constraints on land and water, and as a result, some have argued that future new food demands will only be met through improvements in agricultural productivity on existing irrigated and rainfed cropland, reductions in field losses and food waste, and social changes such as dietary preferences. This talk will address the central role that improvements in water-use productivity can play in the food/water/population nexus. In particular, the ability to grow more food with less water will have a great influence on whether future food demands will be met successfully. Such improvements can come about through changes in technology, regulatory systems, economic incentives and disincentives, and education of water users. Example of potential savings from three different strategies to improve agricultural water productivity in California. (From Pacific Institute).

  5. Set Up of an Automatic Water Quality Sampling System in Irrigation Agriculture

    NASA Astrophysics Data System (ADS)

    Heinz, Emanuel; Kraft, Philipp; Buchen, Caroline; Frede, Hans-Georg; Aquino, Eugenio; Breuer, Lutz

    2014-05-01

    Climate change has already a large impact on the availability of water resources. Many regions in South-East Asia are assumed to receive less water in the future, dramatically impacting the production of the most important staple food: rice (Oryza sativa L.). Rice is the primary food source for nearly half of the World's population, and is the only cereal that can grow under wetland conditions. Especially anaerobic (flooded) rice fields require high amounts of water but also have higher yields than aerobic produced rice. In the past different methods were developed to reduce the water use in rice paddies, like alternative wetting and drying or the use of mixed cropping systems with aerobic (non-flooded) rice and alternative crops such as maize. A more detailed understanding of water and nutrient cycling in rice-based cropping systems is needed to reduce water use, and requires the investigation of hydrological and biochemical processes as well as transport dynamics at the field scale. New developments in analytical devices permit monitoring parameters at high temporal resolutions and at acceptable costs without much necessary maintenance or analysis over longer periods. Here we present a new type of automatic sampling set-up that facilitates in situ analysis of hydrometric information, stable water isotopes and nitrate concentrations in spatially differentiated agricultural fields. The system facilitates concurrent monitoring of a large number of water and nutrient fluxes (ground, surface, irrigation and rain water) in irrigated agriculture. For this purpose we couple an automatic sampling system with a Wavelength-Scanned Cavity Ring Down Spectrometry System (WS-CRDS) for stable water isotope analysis (δ2H and δ18O), a reagentless hyperspectral UV photometer for monitoring nitrate content and various water level sensors for hydrometric information. The whole system is maintained with special developed software for remote control of the system via internet. We

  6. The agricultural water footprint of EU river basins

    NASA Astrophysics Data System (ADS)

    Vanham, Davy

    2014-05-01

    This work analyses the agricultural water footprint (WF) of production (WFprod,agr) and consumption (WFcons,agr) as well as the resulting net virtual water import (netVWi,agr) for 365 EU river basins with an area larger than 1000 km2. Apart from total amounts, also a differentiation between the green, blue and grey components is made. River basins where the WFcons,agr,tot exceeds WFprod,agr,tot values substantially (resulting in positive netVWi,agr,tot values), are found along the London-Milan axis. River basins where the WFprod,agr,totexceeds WFcons,agr,totare found in Western France, the Iberian Peninsula and the Baltic region. The effect of a healthy (HEALTHY) and vegetarian (VEG) diet on the WFcons,agr is assessed, as well as resulting changes in netVWi,agr. For HEALTHY, the WFcons,agr,tot of most river basins decreases (max 32%), although in the east some basins show an increase. For VEG, in all but one river basins a reduction (max 46%) in WFcons,agr,tot is observed. The effect of diets on the WFcons,agrof a river basin has not been carried out so far. River basins and not administrative borders are the key geographical entity for water management. Such a comprehensive analysis on the river basin scale is the first in its kind. Reduced river basin WFcons,agrcan contribute to sustainable water management both within the EU and outside its borders. They could help to reduce the dependency of EU consumption on domestic and foreign water resources.

  7. Agriculture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agriculture within the United States is varied and produces a large value ($200 billion in 2002) of production across a wide range of plant and animal production systems. Because of this diversity, changes in climate will likely impact agriculture throughout the United States. Climate affects crop, ...

  8. Cell-based Metabolomics for Monitoring Ecological Impacts of Environmental Surface Waters

    EPA Science Inventory

    Numerous surface waters are adversely impacted by contaminants released from sources such as WWfPs, CAFOs, mining activities, and agricultural operations. Ideally, an assessment strategy for these applications would include both chemical identification and effects-based monitorin...

  9. Nonstationary time series analysis of surface water microbial pathogen population dynamics using cointegration methods

    EPA Science Inventory

    Background/Question/Methods Bacterial pathogens in surface water present disease risks to aquatic communities and for human recreational activities. Sources of these pathogens include runoff from urban, suburban, and agricultural point and non-point sources, but hazardous micr...

  10. A statewide network for monitoring agricultural water quality and water quantity in Arkansas

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Arkansas produces the most rice, 3rd most cotton and 2nd most broilers of any state in the US. By 2050, agriculture will be asked to produce twice as much food, feed, and fiber for the projected world population, while challenged with reduced water availability from groundwater decline and increase...

  11. Water quality and agricultural practices: the case study of southern Massaciuccoli reclaimed land (Tuscany, Italy)

    NASA Astrophysics Data System (ADS)

    Pistocchi, Chiara; Baneschi, Ilaria; Basile, Paolo; Cannavò, Silvia; Guidi, Massimo; Risaliti, Rosalba; Rossetto, Rudy; Sabbatini, Tiziana; Silvestri, Nicola; Bonari, Enrico

    2010-05-01

    Owing to increasing anthropogenic impacts, lagoons and wetlands are being exposed to environmental degradation. Therefore, the sustainable management of these environmental resources is a fundamental issue to maintain either the ecosystems and the human activity. The Massaciuccoli Lake is a coastal lake of fresh to brackish water surrounded by a marsh, which drains a total catchment of about 114 km2. Large part of the basin has been reclaimed since 1930 by means of pumping stations forcing water from the drained areas into the lake. The system is characterized by: high complexity of the hydrological setting; subsidence of the peaty soils in the reclaimed area (2 to 3 m in 70 years), that left the lake perched; reclaimed land currently devoted mainly to conventional agriculture (e.g.: maize monoculture) along with some industrial sites, two sewage treatment plants and some relevant urban settlements; social conflicts among different land users because of the impact on water quality and quantity. The interaction between such a fragile natural system and human activities leads to an altered ecological status mainly due to eutrophication and water salinisation. Hence, the present work aims at identifying and assessing the sources of nutrients (phosphorous in particular) into the lake, and characterising land use and some socio-economic aspects focusing on agricultural systems, in order to set up suitable mitigation measures. Water quantity and quality in the most intensively cultivated sub-catchment, placed 0.5 to 3 m under m.s.l. were monitored in order to underlain the interaction between water and its nutrient load. Questionnaires and interviews to farmers were conducted to obtain information about agricultural practices, farm management, risks and constraints for farming activities. The available information about the natural system and land use were collected and organised in a GIS system: a conceptual model of surface water hydrodinamics was build up and 14

  12. Belowground Water Dynamics Under Contrasting Annual and Perennial Plant Communities in an Agriculturally-Dominated Landscape

    NASA Astrophysics Data System (ADS)

    Mora, G.; Asbjornsen, H.; Helmers, M. J.; Shepherd, G. W.

    2005-12-01

    The conversion from grasslands and forests to row-crops in the Midwest has affected soil water cycling because plant characteristics are one of the main parameters determining soil storage capacity, infiltration rates, and surface runoff. Little is known, however, about the extent of modification of soil water dynamics under different plant communities. To address this important issue, we are documenting soil water dynamics under contrasting perennial and annual plant communities in an agriculturally-dominated landscape. Measurements of soil moisture and depths of uptake of source water were obtained for six vegetative cover types (corn and soybean field, brome pasture, degraded savanna, restored savanna, and restored prairie) at the Neal Smith National Wildlife Refuge in Prairie City, Iowa. The depths of uptake of soil water were determined on the basis of oxygen isotope composition of soil water and stem water. Measurements were performed once a month during an entire growing season. Preliminary results indicate that soil water present under the different vegetation types show similar profiles with depth during the dry months. Soil water in the upper 5 cm is enriched in oxygen-18 by about 5 per mil relative to soil water at 100 cm. Our preliminary results also indicate that the isotopic composition of stem water from annual plants is typically higher by about 2 per mil relative to that of stem water from perennial plants during the dry period. Whereas the oxygen isotopic composition for corn stem water is -5.49 per mil, that for elm and oak stem water is -7.62 and -7.51 per mil, respectively. The higher isotope values for corn suggest that annual crop plants are withdrawing water from shallower soil horizons relative to perennial plants. Moreover, our preliminary data suggest lower moisture content in soil under annual plant cover. We propose that the presence of deeper roots in the perennial vegetation allows these plants to tap into deeper water sources when

  13. An integrated stochastic approach to the assessment of agricultural water demand and adaptation to water scarcity

    NASA Astrophysics Data System (ADS)

    Foster, T.; Butler, A. P.; McIntyre, N.

    2012-12-01

    Increasing water demands from growing populations coupled with changing water availability, for example due to climate change, are likely to increase water scarcity. Agriculture will be exposed to risk due to the importance of reliable water supplies as an input to crop production. To assess the efficiency of agricultural adaptation options requires a sound understanding of the relationship between crop growth and water application. However, most water resource planning models quantify agricultural water demand using highly simplified, temporally lumped estimated crop-water production functions (CWPFs). Such CWPFs fail to capture the biophysical complexities in crop-water relations and mischaracterise farmers ability to respond to water scarcity. Application of these models in policy analyses will be ineffective and may lead to unsustainable water policies. Crop simulation models provide an alternative means of defining the complex nature of the CWPF. Here we develop a daily water-limited crop model for this purpose. The model is based on the approach used in the FAO's AquaCrop model, balancing biophysical and computational complexities. We further develop the model by incorporating improved simulation routines to calculate the distribution of water through the soil profile. Consequently we obtain a more realistic representation of the soil water balance with concurrent improvements in the prediction of water-limited yield. We introduce a methodology to utilise this model for the generation of stochastic crop-water production functions (SCWPFs). This is achieved by running the model iteratively with both time series of climatic data and variable quantities of irrigation water, employing a realistic rule-based approach to farm irrigation scheduling. This methodology improves the representation of potential crop yields, capturing both the variable effects of water deficits on crop yield and the stochastic nature of the CWPF due to climatic variability. Application to

  14. Water surface capturing by image processing

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An alternative means of measuring the water surface interface during laboratory experiments is processing a series of sequentially captured images. Image processing can provide a continuous, non-intrusive record of the water surface profile whose accuracy is not dependent on water depth. More trad...

  15. Estimation of soil water content for engineering and agricultural applications using ground penetrating radar

    NASA Astrophysics Data System (ADS)

    Grote, Katherine Rose

    2003-10-01

    Near-surface water content is important for a variety of applications in engineering, agriculture, ecology, and environmental monitoring and is an essential input parameter for hydrological and atmospheric models. Water content is both spatially and temporally variable and is difficult to characterize using conventional measurement techniques, which are invasive, time-consuming to collect, and provide only a limited number of point measurements. The purpose of this study is to investigate ground penetrating radar (GPR) techniques for improved estimation of water content. GPR techniques have potential for providing accurate, high-resolution estimates of water content quickly and non-invasively, but the efficacy of these techniques for field-scale applications has not been previously determined. This study begins with a literature review of the application of GPR techniques for water content estimation, followed by a description of the principles employed in GPR surveying and the general methodology for converting electromagnetic GPR measurements to water content estimates. Next, a pilot experiment using GPR techniques for water content estimation is described; this experiment was performed under very controlled conditions and used common-offset GPR reflections to estimate the water content in sandy test pits. This experiment showed that GPR techniques can estimate water content very accurately (within 0.017 cm3/cm3 of the volumetric water content estimates obtained gravimetrically) and provided motivation for the second, less-controlled experiment. The second study used common-offset GPR reflections to estimate water content in a transportation engineering application, where the GPR data were used to monitor the water content in sub-asphalt aggregate layers and to estimate deformation under dynamic loading. This experiment showed that GPR data could be used to accurately monitor changes in the horizontal and vertical distributions of sub-asphalt water content with

  16. Ground water and surface water; a single resource

    USGS Publications Warehouse

    Winter, Thomas C.; Harvey, Judson W.; Franke, O. Lehn; Alley, William M.

    1998-01-01

    The importance of considering ground water and surface water as a single resource has become increasingly evident. Issues related to water supply, water quality, and degradation of aquatic environments are reported on frequently. The interaction of ground water and surface water has been shown to be a significant concern in many of these issues. Contaminated aquifers that discharge to streams can result in long-term contamination of surface water; conversely, streams can be a major source of contamination to aquifers. Surface water commonly is hydraulically connected to ground water, but the interactions are difficult to observe and measure. The purpose of this report is to present our current understanding of these processes and activities as well as limitations in our knowledge and ability to characterize them.

  17. Food, water, and fault lines: Remote sensing opportunities for earthquake-response management of agricultural water.

    PubMed

    Rodriguez, Jenna; Ustin, Susan; Sandoval-Solis, Samuel; O'Geen, Anthony Toby

    2016-09-15

    Earthquakes often cause destructive and unpredictable changes that can affect local hydrology (e.g. groundwater elevation or reduction) and thus disrupt land uses and human activities. Prolific agricultural regions overlie seismically active areas, emphasizing the importance to improve our understanding and monitoring of hydrologic and agricultural systems following a seismic event. A thorough data collection is necessary for adequate post-earthquake crop management response; however, the large spatial extent of earthquake's impact makes challenging the collection of robust data sets for identifying locations and magnitude of these impacts. Observing hydrologic responses to earthquakes is not a novel concept, yet there is a lack of methods and tools for assessing earthquake's impacts upon the regional hydrology and agricultural systems. The objective of this paper is to describe how remote sensing imagery, methods and tools allow detecting crop responses and damage incurred after earthquakes because a change in the regional hydrology. Many remote sensing datasets are long archived with extensive coverage and with well-documented methods to assess plant-water relations. We thus connect remote sensing of plant water relations to its utility in agriculture using a post-earthquake agrohydrologic remote sensing (PEARS) framework; specifically in agro-hydrologic relationships associated with recent earthquake events that will lead to improved water management. PMID:27241204

  18. Differences in Aquatic Communities Between Wetlands Created by an Agricultural Water Recycling System

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Establishment of an agricultural water recycling system known as the wetland reservoir subirrigation system (WRSIS) results in the creation of wetlands adjacent to agricultural fields. Each WRSIS consists of one wetland designed to process agricultural chemicals (WRSIS wetlands) and one wetland to s...

  19. Surface water records of Colorado, 1961

    USGS Publications Warehouse

    U.S. Geological Survey, Water Resources Division

    1961-01-01

    The surface-water records for the 1961 water year for gaging stations and miscellaneous sites within the State of Colorado are given in this report. For convenience there are also included records for a few pertinent gaging stations in bordering States. The records were collected and computed by the Water Resources Division of the U.S. Geological Survey, under the direction of W. T. Miller, district engineer, Surface Water Branch, succeeded by J. W. Odell.

  20. Food vs. water: the magnitude and range of global tradeoffs in agricultural production and impact

    NASA Astrophysics Data System (ADS)

    Brauman, K. A.; Flörke, M.; Mueller, N. D.; Foley, J. A.

    2013-12-01

    Water is integral to agricultural production, and agriculture is by far the largest human use of water, so food security and water sustainability are inexorably linked. When water goes to food production, however, the benefits and costs are not uniformly distributed across the globe. We quantify the magnitude and global range of the multidimensional tradeoffs among food production, water consumption, and water quality impairment. To evaluate the productivity of water consumption in agriculture, we quantified the magnitude and global range of crop water productivity, the amount of food produced per unit of water consumed, for 16 major food crops (Brauman et al., 2013). We now expand on this, contextualizing the impact of high or low water productivity with information about water availability. Using outputs from the WaterGAP3 model (Flörke et al., 2013, Verzano et al. 2012), we map the burden of agricultural water consumption on total water availability. To incorporate impacts of agriculture on water quality, we include areas of excess nutrient application (Mueller et al., 2012). The integrated information about yield, water consumption, water availability, and nutrient application shows that benefits and impacts to water quantity and quality are not evenly distributed. Analogous to previous investigations of 'yield gaps,' which identified areas where biophysical conditions are sufficient for achieving yields higher than those that are attained (Licker et al., 2010), we show that in many places, for the given impacts to water, food production could be increased.

  1. Water quality monitoring of an agricultural watershed lake: the effectiveness of agricultural best management practices

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Beasley Lake is an oxbow lake located in the Lower Mississippi Alluvial Plain (the Delta), a region of intensive agricultural activity. Due to intensive row-crop agricultural practices, the 915 ha watershed was sediment impaired when monitoring began in 1995 and was a candidate to assess the effect...

  2. Water availability, water demand, and reliability of in situ water harvesting in smallholder rain-fed agriculture in the Thukela River Basin, South Africa

    NASA Astrophysics Data System (ADS)

    Andersson, J. C. M.; Zehnder, A. J. B.; Jewitt, G. P. W.; Yang, H.

    2009-07-01

    Water productivity in smallholder rain-fed agriculture is of key interest for food and livelihood security. A frequently advocated approach to enhance water productivity is to adopt water harvesting and conservation technologies (WH). This study estimates water availability for in situ WH and supplemental water demands (SWD) in smallholder agriculture in the Thukela River Basin, South Africa. It incorporates process dynamics governing runoff generation and crop water demands, an explicit account of the reliability of in situ WH, and uncertainty considerations. The agro-hydrological model SWAT (Soil and Water Assessment Tool) was calibrated and evaluated with the SUFI-2 algorithm against observed crop yield and discharge in the basin. The water availability was based on the generated surface runoff in smallholder areas. The SWD was derived from a scenario where crop water deficits were met from an unlimited external water source. The reliability was calculated as the percentage of years in which the water availability ≥ the SWD. It reflects the risks of failure induced by the temporal variability in these factors. The results show that the smallholder crop water productivity is low in the basin (spatiotemporal median: 0.08-0.22 kg m-3, 95% prediction uncertainty band (95PPU). Water is available for in situ WH (spatiotemporal median: 0-17 mm year-1, 95PPU) which may aid in enhancing the crop water productivity by meeting some of the SWD (spatiotemporal median: 0-113 mm year-1, 95PPU). However, the reliability of in situ WH is highly location specific and overall rather low. Of the 1850 km2 of smallholder lands, 20-28% display a reliability ≥25%, 13-16% a reliability ≥50%, and 4-5% a reliability ≥75% (95PPU). This suggests that the risk of failure of in situ WH is relatively high in many areas of the basin.

  3. Relevance of urban glyphosate use for surface water quality.

    PubMed

    Hanke, Irene; Wittmer, Irene; Bischofberger, Simone; Stamm, Christian; Singer, Heinz

    2010-09-01

    Relative contributions of agricultural and urban uses to the glyphosate contamination of surface waters were studied in a small catchment (25 km(2)) in Switzerland. Monitoring in four sub-catchments with differing land use allowed comparing load and input dynamics from different sources. Agricultural as well as urban use was surveyed in all sub-catchments allowing for a detailed interpretation of the monitoring results. Water samples from the river system and from the urban drainage system (combined sewer overflow, storm sewer and outflow of wastewater treatment plant) were investigated. The concentrations at peak discharge during storm events were elevated throughout the year with maximum concentrations of 4.15 μg L(-1). Glyphosate concentrations mostly exceeded those of other commonly used herbicides such as atrazine or mecoprop. Fast runoff from hard surfaces led to a fast increase of the glyphosate concentration shortly after the beginning of rainfall not coinciding with the concentration peak normally observed from agricultural fields. The comparison of the agricultural application and the seasonal concentration and load pattern in the main creek from March to November revealed that the occurrence of glyphosate cannot be explained by agricultural use only. Extrapolations from agricultural loss rates and from concentrations found in the urban drainage system showed that more than half of the load during selected rain events originates from urban areas. The inputs from the effluent of the wastewater treatment plant, the overflow of the combined sewer system and of the separate sewer system summed up to 60% of the total load. PMID:20696461

  4. Assessment of impacts of agricultural and climate change scenarios on watershed water quantity and quality, and crop production

    NASA Astrophysics Data System (ADS)

    Teshager, Awoke D.; Gassman, Philip W.; Schoof, Justin T.; Secchi, Silvia

    2016-08-01

    Modeling impacts of agricultural scenarios and climate change on surface water quantity and quality provides useful information for planning effective water, environmental and land use policies. Despite the significant impacts of agriculture on water quantity and quality, limited literature exists that describes the combined impacts of agricultural land use change and climate change on future bioenergy crop yields and watershed hydrology. In this study, the soil and water assessment tool (SWAT) eco-hydrological model was used to model the combined impacts of five agricultural land use change scenarios and three downscaled climate pathways (representative concentration pathways, RCPs) that were created from an ensemble of eight atmosphere-ocean general circulation models (AOGCMs). These scenarios were implemented in a well-calibrated SWAT model for the intensively farmed and tiled Raccoon River watershed (RRW) located in western Iowa. The scenarios were executed for the historical baseline, early century, mid-century and late century periods. The results indicate that historical and more corn intensive agricultural scenarios with higher CO2 emissions consistently result in more water in the streams and greater water quality problems, especially late in the 21st century. Planting more switchgrass, on the other hand, results in less water in the streams and water quality improvements relative to the baseline. For all given agricultural landscapes simulated, all flow, sediment and nutrient outputs increase from early-to-late century periods for the RCP4.5 and RCP8.5 climate scenarios. We also find that corn and switchgrass yields are negatively impacted under RCP4.5 and RCP8.5 scenarios in the mid- and late 21st century.

  5. Increasing Efficiency of Water Use in Agriculture through Management of Soil Water Repellency to Optimize Soil and Water Productivity

    NASA Astrophysics Data System (ADS)

    Moore, Demie; Kostka, Stan; McMillan, Mica; Gadd, Nick

    2010-05-01

    Water's ability to infiltrate and disperse in soils, and soil's ability to receive, transport, retain, filter and release water are important factors in the efficient use of water in agriculture. Deteriorating soil conditions, including development of soil water repellency, negatively impact hydrological processes and, consequently, the efficiency of rainfall and irrigation. Soil water repellency is increasingly being identified in diverse soils and cropping systems. Recently research has been conducted on the use of novel soil surfactants (co-formulations of alkyl polyglycoside and block copolymer surfactants) to avoid or overcome soil water repellency and enhance water distribution in soils. Results indicate that this is an effective and affordable approach to maintaining or restoring soil and water productivity in irrigated cropping systems. Results from studies conducted in Australia and the United States to determine how this technology modifies soil hydrological behavior and crop yields will be presented. A range of soils and various crops, including potatoes, corn, apples and grapes, were included. Several rates were compared to controls for effect on soil moisture levels, soil water distribution, and crop yield. An economic analysis was also conducted in some trials. Treatments improved rootzone water status, significantly increased crop yield and quality, and in some cases allowed significant reductions in water requirements. Where assessed, a positive economic return was generated. This technology holds promise as a strategy for increasing efficiency of water use in agriculture.

  6. New technological methods for protecting underground waters from agricultural pollution

    NASA Astrophysics Data System (ADS)

    Mavlyanov, Gani

    2015-04-01

    The agricultural production on the irrigated grounds can not carry on without mineral fertilizers, pesticides and herbicides. Especially it is shown in Uzbekistan, in cultivation of cotton. There is an increase in mineralization, rigidity, quantity of heavy metals, phenols and other pollutions in the cotton fields. Thus there is an exhaustion of stocks of fresh underground waters. In the year 2003 we were offered to create the ecological board to prevent pollution to get up to a level of subsoil waters in the top 30 centimeter layer of the ground. We carried out an accumulation and pollution processing. This layer possesses a high adsorbing ability for heavy metals, mineral oil, mineral fertilizers remnants, defoliants and pesticides. In order to remediate a biological pollution treatment processing should be take into account. The idea is consisted in the following. The adsorption properties of coal is all well-known that the Angren coal washing factories in Tashkent area have collected more than 10 million tons of the coal dust to mix with clays. We have picked up association of anaerobic microorganisms which, using for development, destroys nutrients of coal waste pollutions to a harmless content for people. Coal waste inoculation also are scattered by these microorganisms on the field before plowing. Deep (up to 30 cm) plowing brings them on depth from 5 up to 30 cm. Is created by a plough a layer with necessary protective properties. The norm of entering depends on the structure of ground and the intensity of pollutions. Laboratory experiments have shown that 50% of pollutions can be treated by the ecological board and are processed up to safe limit.

  7. The water footprint of agricultural products in European river basins

    NASA Astrophysics Data System (ADS)

    Vanham, D.; Bidoglio, G.

    2014-05-01

    This work quantifies the agricultural water footprint (WF) of production (WFprod, agr) and consumption (WFcons, agr) and the resulting net virtual water import (netVWi, agr) of 365 European river basins for a reference period (REF, 1996-2005) and two diet scenarios (a healthy diet based upon food-based dietary guidelines (HEALTHY) and a vegetarian (VEG) diet). In addition to total (tot) amounts, a differentiation is also made between the green (gn), blue (bl) and grey (gy) components. River basins where the REF WFcons, agr, tot exceeds the WFprod, agr, tot (resulting in positive netVWi, agr, tot values), are found along the London-Milan axis. These include the Thames, Scheldt, Meuse, Seine, Rhine and Po basins. River basins where the WFprod, agr, tot exceeds the WFcons, agr, tot are found in Western France, the Iberian Peninsula and the Baltic region. These include the Loire, Ebro and Nemunas basins. Under the HEALTHY diet scenario, the WFcons, agr, tot of most river basins decreases (max -32%), although it was found to increase in some basins in northern and eastern Europe. This results in 22 river basins, including the Danube, shifting from being net VW importers to being net VW exporters. A reduction (max -46%) in WFcons, agr, tot is observed for all but one river basin under the VEG diet scenario. In total, 50 river basins shift from being net VW importers to being net exporters, including the Danube, Seine, Rhone and Elbe basins. Similar observations are made when only the gn + bl and gn components are assessed. When analysing only the bl component, a different river basin pattern is observed.

  8. Set up of an automatic water quality sampling system in irrigation agriculture.

    PubMed

    Heinz, Emanuel; Kraft, Philipp; Buchen, Caroline; Frede, Hans-Georg; Aquino, Eugenio; Breuer, Lutz

    2013-01-01

    We have developed a high-resolution automatic sampling system for continuous in situ measurements of stable water isotopic composition and nitrogen solutes along with hydrological information. The system facilitates concurrent monitoring of a large number of water and nutrient fluxes (ground, surface, irrigation and rain water) in irrigated agriculture. For this purpose we couple an automatic sampling system with a Wavelength-Scanned Cavity Ring Down Spectrometry System (WS-CRDS) for stable water isotope analysis (δ2H and δ18O), a reagentless hyperspectral UV photometer (ProPS) for monitoring nitrate content and various water level sensors for hydrometric information. The automatic sampling system consists of different sampling stations equipped with pumps, a switch cabinet for valve and pump control and a computer operating the system. The complete system is operated via internet-based control software, allowing supervision from nearly anywhere. The system is currently set up at the International Rice Research Institute (Los Baños, The Philippines) in a diversified rice growing system to continuously monitor water and nutrient fluxes. Here we present the system's technical set-up and provide initial proof-of-concept with results for the isotopic composition of different water sources and nitrate values from the 2012 dry season. PMID:24366178

  9. Set Up of an Automatic Water Quality Sampling System in Irrigation Agriculture

    PubMed Central

    Heinz, Emanuel; Kraft, Philipp; Buchen, Caroline; Frede, Hans-Georg; Aquino, Eugenio; Breuer, Lutz

    2014-01-01

    We have developed a high-resolution automatic sampling system for continuous in situ measurements of stable water isotopic composition and nitrogen solutes along with hydrological information. The system facilitates concurrent monitoring of a large number of water and nutrient fluxes (ground, surface, irrigation and rain water) in irrigated agriculture. For this purpose we couple an automatic sampling system with a Wavelength-Scanned Cavity Ring Down Spectrometry System (WS-CRDS) for stable water isotope analysis (δ2H and δ18O), a reagentless hyperspectral UV photometer (ProPS) for monitoring nitrate content and various water level sensors for hydrometric information. The automatic sampling system consists of different sampling stations equipped with pumps, a switch cabinet for valve and pump control and a computer operating the system. The complete system is operated via internet-based control software, allowing supervision from nearly anywhere. The system is currently set up at the International Rice Research Institute (Los Baños, The Philippines) in a diversified rice growing system to continuously monitor water and nutrient fluxes. Here we present the system's technical set-up and provide initial proof-of-concept with results for the isotopic composition of different water sources and nitrate values from the 2012 dry season. PMID:24366178

  10. Quantifying subsurface mixing of water and nutrients in an agricultural catchment

    NASA Astrophysics Data System (ADS)

    Van der Velde, Y.; Torfs, P.; Van Der Zee, S.; Uijlenhoet, R.

    2011-12-01

    The distribution of time it takes water from the moment of rainfall to reach the catchment outlet is widely used to characterize catchment-scale groundwater-surface water interactions, catchment vulnerability to pollution spreading and pollutant loads from catchments to downstream waters. However, this distribution tends to vary in time driven by rainfall and evapotranspiration, which compromises the applicability of a single travel time distribution as catchment characteristic. Recent studies suggested that subsurface mixing controls to what extent dynamics in rainfall and evpotranspiration are translated into dynamics of travel time distributions of individual water flows. This new insight in hydrologic functioning of catchments requires new definitions and concepts that link dynamics of catchment travel time distributions to the degree of subsurface mixing. We propose the concept of Refresh Rate Functions (RRF) and will demonstrate how RRFs directly quantify subsurface mixing within a catchment, allow for deriving transient as well as temporally averaged travel time distributions of a catchment and are largely independent of weather or climate. The presented analyses will use a unique dataset of high-frequent nitrate concentrations in an agricultural catchment in the Netherlands to reveal the effects of mixing dynamics inside a catchment on stream water nitrate concentrations. These measurements will be compared with calculations by a spatially distributed groundwater model and conceptual models of water flow and solute transport. Remarkable findings are the large contrasts in discharge behavior expressed in travel time between lowland and sloping catchments and the strong relation between evapotranspiration and stream water nitrate concentration dynamics.