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Sample records for agriculture continued water

  1. Agriculture and water quality. Agriculture Information Bulletin

    SciTech Connect

    Crowder, B.M.; Ribaudo, M.O.; Young, C.E.

    1988-08-01

    Agriculture generates byproducts that may contribute to the contamination of the Nation's 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 waterways in runoff; some leach through soil into ground water. Because surface-water systems and ground water systems are interrelated, farm-management practices need to focus on water quality in both systems. Modifying farm-management practices may raise production costs in some areas. Farmers can reduce runoff losses by reducing input use, implementing soil-conservation practices, and changing land use. Also at issue is who should pay for improving water quality.

  2. 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.

  3. Use of real-time and continuous water quality monitoring in Iowa streams to inform conservation strategy in an agricultural landscape

    NASA Astrophysics Data System (ADS)

    Jones, C. S.; Kim, S. W.; Davis, C. A.

    2015-12-01

    Agricultural watersheds in the Midwestern U.S. are major contributors of nutrients to the Mississippi River Basin and the Gulf of Mexico. Many states within the Upper Mississippi River Basin, including Iowa, are developing nutrient reduction strategies to reduce non-point and point source loads of nitrogen and phosphorous in an effort to reverse degradation of streams and lakes. Quantifying nutrient loads in Iowa and assessing loads transported within Iowa rivers are important components of Iowa's strategy. Nutrient loads estimated with data collected using traditional methods of grab sampling are expensive and have met with limited usefulness to the agricultural community when assessing the effectiveness of implemented conservation practices. New sensor technology is allowing for real-time measurement of nutrient loads in many Iowa rivers. IIHR Hydroscience and Engineering has deployed 22 nitrate-nitrogen sensors in several Iowa rivers to provide accurate measure of nutrient loads. Combined with 17 sensors operated by the USGS, the sensor network captures nutrient transport and loading patterns in rivers across the state. A new Iowa Water Quality Information System (IWQIS) is being developed to display and share the continuous, real-time data. The data reported here will compare and contrast load calculations obtained using continuous monitors with those from a more traditional grab samples. We also will demonstrate how continuous nitrate monitoring informs watershed hydrology and the assessment of conservation practices designed to reduce nutrient loss from farmed fields. Finally, we will establish that the costs of real time continuous monitoring are modest when compared to grab sampling strategies and the costs of implementing conservation on productive lands in the Western Corn Belt of Iowa.

  4. Agricultural use of water.

    PubMed

    Collett, J R

    1980-07-28

    Irrigation for agricultural purposes is one of the essential claims on available water resources. Those resources have not been adequately utilized in many countries for a variety of reasons. Where finance has been allocated to irrigation schemes, the schemes have tended to be large-scale, and the performance often disappointing. Alternatively, small-scale irrigation schemes, while receiving less support and encouragement, can often be more effective. For both large-scale and small-scale irrigation schemes, the responses of individual farmers and village communities are critical factors. More technologies need to be developed that are adapted to local needs, resources and aspirations within the context of current socio-economic practices. Obviously, the wider the range of technologies available, the more likely it will be that the technology most appropriate to existing conditions will be identified and used.

  5. Perceived agricultural runoff impact on drinking water.

    PubMed

    Crampton, Andrea; Ragusa, Angela T

    2014-09-01

    Agricultural runoff into surface water is a problem in Australia, as it is in arguably all agriculturally active countries. While farm practices and resource management measures are employed to reduce downstream effects, they are often either technically insufficient or practically unsustainable. Therefore, consumers may still be exposed to agrichemicals whenever they turn on the tap. For rural residents surrounded by agriculture, the link between agriculture and water quality is easy to make and thus informed decisions about water consumption are possible. Urban residents, however, are removed from agricultural activity and indeed drinking water sources. Urban and rural residents were interviewed to identify perceptions of agriculture's impact on drinking water. Rural residents thought agriculture could impact their water quality and, in many cases, actively avoided it, often preferring tank to surface water sources. Urban residents generally did not perceive agriculture to pose health risks to their drinking water. Although there are more agricultural contaminants recognised in the latest Australian Drinking Water Guidelines than previously, we argue this is insufficient to enhance consumer protection. Health authorities may better serve the public by improving their proactivity and providing communities and water utilities with the capacity to effectively monitor and address agricultural runoff.

  6. Continuous Passive Sampling of Solutes from Agricultural Subsurface Drainage Tubes

    NASA Astrophysics Data System (ADS)

    Lindblad Vendelboe, Anders; de Jonge, Hubert; Rozemeijer, Joachim; Wollesen de Jonge, Lis

    2015-04-01

    Agricultural subsurface tube drain systems play an important role in water and solute transport. One study, focusing on lowland agricultural catchments, showed that subsurface tube drainage contributed up to 80% of the annual discharge and 90% of the annual NO3 load from agricultural fields to the receiving water bodies. Knowledge of e.g. nutrient loads and drainage volumes, based on measurements and modelling, are important for adequate water quality management. Despite the importance of tube drain transport of solutes, monitoring data are scarce. This scarcity is a result of the existing monitoring techniques for flow and contaminant load from tube drains being expensive and labor-extensive. The study presented here aimed at developing a cheap, simple, and robust method to monitor solute loads from tube drains. The method is based on the newly developed Flowcap, which can be attached to existing tube drain outlets and can measure total flow, contaminant load and flow-averaged concentrations of solutes in the drainage. The Flowcap builds on the existing Sorbicell principle, a passive sampling system that measures average concentrations over longer periods of time (days to months) for various compounds. The Sorbicell consists of two compartments permeable to water. One compartment contains an adsorbent and one contains a tracer. When water passes through the Sorbicell the compound of interest is absorbed while a tracer is released. Using the tracer loss to calculate the volume of water that has passed the Sorbicell it is possible to calculate the average concentration of the compound. When mounting Sorbicells in the Flowcap, a flow-proportional part of the drainage is sampled from the main stream. To accommodate the wide range of drainage flow rates two Flowcaps with different capacities were tested in the laboratory: one with a capacity of 25 L min-1 (Q25) and one with a capacity of 256 L min-1 (Q256). In addition, Sorbicells with two different hydraulic

  7. 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…

  8. 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

  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.

  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. Seasonal water demand in Benin's agriculture.

    PubMed

    Gruber, Ina; Kloos, Julia; Schopp, Marion

    2009-01-01

    This paper describes and analyzes agricultural water demands for Benin, West Africa. Official statistical data regarding water quantities as well as knowledge on factors influencing the demand for water are extremely rare and often reveal national trends without considering regional or local differences. Thus policy makers usually work with this estimated and aggregated data, which make it very difficult to adequately address regional and local development goals. In the framework of an interdisciplinary analysis the following paper provides insight into water quantification and detects water problems under seasonal aspects for agriculture according to regional differences. Following the definition of the Food and Agriculture Organization [FAO, 1995. Water Report 7. Irrigation in Africa in Figures. Rome] agriculture is divided into irrigation and livestock watering, which were analyzed using different field methods. The study reveals that although water supply in absolute terms seems to be sufficient in Benin, seasonal water problems occur both in irrigation and in livestock management. Thus arising seasonal water problems are not the consequence of general water scarcity but more linked to three major problems. These problems emerge from difficulties in technical equipment and financial means of farmers, from the specific local conditions influencing the access to water sources and the extraction of groundwater, and third from the overall low organizational structure of water management. Therefore regional differences as well as a general improvement of knowledge on better management structures, technical know how, and access to credits for farmers need to be considered in national strategies in order to improve the agricultural water usage in Benin.

  12. 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.

  13. Agricultural water pollution control: An interdisciplinary approach

    NASA Astrophysics Data System (ADS)

    Miller, Watkins W.; Ching, Chauncey T. K.; Yanagida, John F.; Jakus, Paul

    1985-01-01

    Regulation and control of agricultural water pollution is unique and difficult to accomplish. Water quality standards are often proposed without adequate consideration of the overall economic impact on agricultural production. This article illustrates how economists and physical scientists can cooperate to develop appropriate control strategies for agricultural water pollution. Data provided by physical scientists and economists are used in a linear programming model to describe salt discharge as a function of water management, production levels, and an associated effluent charge. Four water management activities were chosen on the basis of different costs of production (including a parametrically varied effluent charge), water requirements, alfalfa yields, and levels of salt discharge. Results indicate that when the effluent charge is low (<0.20/metric ton salt discharged), maximum production with maximum salt discharge is most profitable. As the effluent charge is increased (0.20 0.40/metric ton salt discharged), it becomes progressively less profitable to produce alfalfa at maximum levels of pollutant discharge. When the effluent charge is >0.40/metric ton salt discharged, alfalfa production is no longer economically feasible. An important aspect of this approach is that it permits policy makers to identify explicitly the relationship between the environmental standard and the effect on agricultural production.

  14. 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.

  15. 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...

  16. 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

  17. In-situ continuous water monitoring system

    DOEpatents

    Thompson, Cyril V.; Wise, Marcus B.

    1998-01-01

    An in-situ continuous liquid monitoring system for continuously analyzing volatile components contained in a water source comprises: a carrier gas supply, an extraction container and a mass spectrometer. The carrier gas supply continuously supplies the carrier gas to the extraction container and is mixed with a water sample that is continuously drawn into the extraction container by the flow of carrier gas into the liquid directing device. The carrier gas continuously extracts the volatile components out of the water sample. The water sample is returned to the water source after the volatile components are extracted from it. The extracted volatile components and the carrier gas are delivered continuously to the mass spectrometer and the volatile components are continuously analyzed by the mass spectrometer.

  18. In-situ continuous water monitoring system

    DOEpatents

    Thompson, C.V.; Wise, M.B.

    1998-03-31

    An in-situ continuous liquid monitoring system for continuously analyzing volatile components contained in a water source comprises: a carrier gas supply, an extraction container and a mass spectrometer. The carrier gas supply continuously supplies the carrier gas to the extraction container and is mixed with a water sample that is continuously drawn into the extraction container by the flow of carrier gas into the liquid directing device. The carrier gas continuously extracts the volatile components out of the water sample. The water sample is returned to the water source after the volatile components are extracted from it. The extracted volatile components and the carrier gas are delivered continuously to the mass spectrometer and the volatile components are continuously analyzed by the mass spectrometer. 2 figs.

  19. In-situ continuous water analyzing module

    DOEpatents

    Thompson, Cyril V.; Wise, Marcus B.

    1998-01-01

    An in-situ continuous liquid analyzing system for continuously analyzing volatile components contained in a water source comprises: a carrier gas supply, an extraction container and a mass spectrometer. The carrier gas supply continuously supplies the carrier gas to the extraction container and is mixed with a water sample that is continuously drawn into the extraction container. The carrier gas continuously extracts the volatile components out of the water sample. The water sample is returned to the water source after the volatile components are extracted from it. The extracted volatile components and the carrier gas are delivered continuously to the mass spectometer and the volatile components are continuously analyzed by the mass spectrometer.

  20. Atomizing, continuous, water monitoring module

    DOEpatents

    Thompson, Cyril V.; Wise, Marcus B.

    1997-01-01

    A system for continuously analyzing volatile constituents of a liquid is described. The system contains a pump for continuously pumping the liquid to be tested at a predetermined flow rate into an extracting container through a liquid directing tube having an orifice at one end and positioned to direct the liquid into the extracting container at a flow rate sufficient to atomize the liquid within the extracting container. A continuous supply of helium carrier gas at a predetermined flow rate is directed through a tube into the extracting container and co-mingled with the atomized liquid to extract the volatile constituents contained within the atomized liquid. The helium containing the extracted volatile constituents flows out of the extracting container into a mass spectrometer for an analysis of the volatile constituents of the liquid.

  1. Atomizing, continuous, water monitoring module

    DOEpatents

    Thompson, C.V.; Wise, M.B.

    1997-07-08

    A system for continuously analyzing volatile constituents of a liquid is described. The system contains a pump for continuously pumping the liquid to be tested at a predetermined flow rate into an extracting container through a liquid directing tube having an orifice at one end and positioned to direct the liquid into the extracting container at a flow rate sufficient to atomize the liquid within the extracting container. A continuous supply of helium carrier gas at a predetermined flow rate is directed through a tube into the extracting container and co-mingled with the atomized liquid to extract the volatile constituents contained within the atomized liquid. The helium containing the extracted volatile constituents flows out of the extracting container into a mass spectrometer for an analysis of the volatile constituents of the liquid. 3 figs.

  2. Water transfers, agriculture, and groundwater management: a dynamic economic analysis.

    PubMed

    Knapp, Keith C; Weinberg, Marca; Howitt, Richard; Posnikoff, Judith F

    2003-04-01

    Water transfers from agricultural to urban and environmental uses will likely become increasingly common worldwide. Many agricultural areas rely heavily on underlying groundwater aquifers. Out-of-basin surface water transfers will increase aquifer withdrawals while reducing recharge, thereby altering the evolution of the agricultural production/groundwater aquifer system over time. An empirical analysis is conducted for a representative region in California. Transfers via involuntary surface water cutbacks tilt the extraction schedule and lower water table levels and net benefits over time. The effects are large for the water table but more modest for the other variables. Break-even prices are calculated for voluntary quantity contract transfers at the district level. These prices differ considerably from what might be calculated under a static analysis which ignores water table dynamics. Canal-lining implies that districts may gain in the short-run but lose over time if all the reduction in conveyance losses is transferred outside the district. Water markets imply an evolving quantity of exported flows over time and a reduction in basin net benefits under common property usage. Most aquifers underlying major agricultural regions are currently unregulated. Out-of-basin surface water transfers increase stress on the aquifer and management benefits can increase substantially in percentage terms but overall continue to remain small. Conversely, we find that economically efficient management can mitigate some of the adverse consequences of transfers, but not in many circumstances or by much. Management significantly reduced the water table impacts of cutbacks but not annual net benefit impacts. Neither the break-even prices nor the canal-lining impacts were altered by much. The most significant difference is that regional water users gain from water markets under efficient management.

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

    NASA Astrophysics Data System (ADS)

    Appelgren, Bo

    natural resource scarcity. International food trade could provide a powerful means to enhance food security and address water scarcity. However agricultural trade rounds and agreements continues to be dominated by discerning policies that have in general failed do reflect the need for global solidarity and give necessary attention to social and environmental non -trade issues in poor countries. In conclusion the broader dialogue on water and agriculture based on enhanced solidarity will depend on how the society can successfully address, clarify and agree on a number of critical ethical issues. These are related not only to the debate on population, but to approaches to scarcity diagnosis, perceived conflicting objectives of development and biodiversity, reconciliation and implementation of global and domestic water policy and finally an internationally broad-minded and responsible approach to int ernational agricultural trade.

  4. 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...

  5. 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.

  6. 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

  7. Water management, agriculture, and ground-water supplies

    USGS Publications Warehouse

    Nace, Raymond L.

    1960-01-01

    Encyclopedic data on world geography strikingly illustrate the drastic inequity in the distribution of the world's water supply. About 97 percent of the total volume of water is in the world's oceans. The area of continents and islands not under icecaps, glaciers, lakes, and inland seas is about 57.5 million square miles, of which 18 million (36 percent) is arid to semiarid. The total world supply of water is about 326.5 million cubic miles, of which about 317 million is in the oceans and about 9.4 million is in the land areas. Atmospheric moisture is equivalent to only about 3,100 cubic miles of water. The available and accessible supply of ground water in the United States is somewhat more than 53,000 cubic miles (about 180 billion acre ft). The amount of fresh water on the land areas of the world at any one time is roughly 30,300 cubic miles and more than a fourth of this is in large fresh-water lakes on the North American Continent. Annual recharge of ground water in the United States may average somewhat more than 1 billion acre-feet yearly, but the total volume of ground water in storage is equivalent to all the recharge in about the last 160 years. This accumulation of ground water is the nation's only reserve water resource, but already it is being withdrawn or mined on a large scale in a few areas. The principal withdrawals of water in the United States are for agriculture and industry. Only 7.4 percent of agricultural land is irrigated, however; so natural soil moisture is the principal source of agricultural water, and on that basis agriculture is incomparably the largest water user. In view of current forecasts of population and industrial expansion, new commitments of water for agriculture should be scrutinized very closely, and thorough justification should be required. The 17 Western States no longer contain all the large irrigation developments. Nearly 10 percent of the irrigated area is in States east of the western bloc, chiefly in several

  8. Water Quality Significance of Wetlands Receiving Agricultural Drainage

    NASA Astrophysics Data System (ADS)

    Stringfellow, W.; Sharon, B.; Engelage, S.; Hanlon, J.; Graham, J.; Burks, R.

    2007-12-01

    The San Joaquin Valley is one of the most productive agricultural regions in the world and this productivity is heavily dependent on irrigated agricultural. An inevitable consequence of irrigated agricultural is the generation of return-flows conveyed down-gradient in agricultural drains that eventually discharge to surface waters. Agricultural drainage often has poor water quality characteristics, but demand for water in California is high and agricultural drainage is often diverted for secondary use, including the maintenance of ponds and wetlands. Additionally, agricultural drainage often discharges into riparian wetlands, rather than into the open river channel. In this study we tested the hypothesis that wetlands were mitigating or buffering the impact of agricultural drainage and that discharge of agricultural drainage into wetland buffer zones would provide water quality benefits. Water samples were collected at wetland, agricultural, and mixed drainages in the San Joaquin River basin and analyzed for a broad array of physical and chemical water quality parameters, including nutrients and organic carbon. At selected wetlands, input-output studies were conducted to determine wetland specific water quality effects. The water quality of drainages influenced by wetlands was compared to drainages that were predominantly influenced by other types of land-use. Wetland influenced drainages are more likely to have higher DOC concentrations that other drainages, including agricultural and mixed urban-agricultural drains. Wetland dominated drainages had lower nitrates than agricultural drainages and studies of individual wetlands demonstrated that wetlands remove soluble phosphate and nitrate, but produce DOC and biochemical oxygen demand (BOD). Overall land use in a drainage was a less significant determinant of water quality than soil type and the presence or absence of wetlands. The specific trihalomethane formation potential (THMFP) of the DOC from wetland

  9. 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).

  10. 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.

  11. 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, ...

  12. Rice Water use efficiency and yield under continuous and intermittent irrigation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In the Brazilian state of Rio Grande do Sul, rice (Oryza sativa L.) is predominantly grown using continuous fl ood irrigation, which requires large quantities of fresh water. Due to increasing scarcity and demand for water, modern agricultural systems need to produce more food with less water. Th e ...

  13. Continuous extraction of organic materials from water

    USGS Publications Warehouse

    Goldberg, M.C.; DeLong, L.; Kahn, L.

    1971-01-01

    A continuous liquid solvent extractor, designed to utilize organic solvents that are heavier than water, is described. The extractor is capable of handling input rates up to 2 liters per hour and has a 500-ml. extractant capacity. Extraction efficiency is dependent upon the p-value, the two solvent ratios, rate of flow of the aqueous phase, and rate of reflux of the organic phase. Extractors can be serially coupled to increase extraction efficiency and, when coupled with a lighter-than-water extractor, the system will allow the use of any immiscible solvent.

  14. 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

  15. Continuous Monitoring of Plant Water Potential

    PubMed Central

    Schaefer, Nick L.; Trickett, Edward S.; Ceresa, Anthony; Barrs, Henry D.

    1986-01-01

    Plant water potential was monitored continuously with a Wescor HR-33T dewpoint hygrometer in conjunction with a L51 chamber. This commercial instrument was modified by replacing the AC-DC mains power converter with one stabilized by zener diode controlled transistors. The thermocouple sensor and electrical lead needed to be thermally insulated to prevent spurious signals. For rapid response and faithful tracking a low resistance for water vapor movement between leaf and sensor had to be provided. This could be effected by removing the epidermis either by peeling or abrasion with fine carborundum cloth. A variety of rapid plant water potential responses to external stimuli could be followed in a range of crop plants (sunflower (Helianthus annuus L., var. Hysun 30); safflower (Carthamus tinctorious L., var. Gila); soybean (Glycine max L., var. Clark); wheat (Triticum aestivum L., var. Egret). These included light dark changes, leaf excision, applied pressure to or anaerobiosis of the root system. Water uptake by the plant (safflower, soybean) mirrored that for water potential changes including times when plant water status (soybean) was undergoing cyclical changes. PMID:16664805

  16. Continuous monitoring of plant water potential.

    PubMed

    Schaefer, N L; Trickett, E S; Ceresa, A; Barrs, H D

    1986-05-01

    Plant water potential was monitored continuously with a Wescor HR-33T dewpoint hygrometer in conjunction with a L51 chamber. This commercial instrument was modified by replacing the AC-DC mains power converter with one stabilized by zener diode controlled transistors. The thermocouple sensor and electrical lead needed to be thermally insulated to prevent spurious signals. For rapid response and faithful tracking a low resistance for water vapor movement between leaf and sensor had to be provided. This could be effected by removing the epidermis either by peeling or abrasion with fine carborundum cloth. A variety of rapid plant water potential responses to external stimuli could be followed in a range of crop plants (sunflower (Helianthus annuus L., var. Hysun 30); safflower (Carthamus tinctorious L., var. Gila); soybean (Glycine max L., var. Clark); wheat (Triticum aestivum L., var. Egret). These included light dark changes, leaf excision, applied pressure to or anaerobiosis of the root system. Water uptake by the plant (safflower, soybean) mirrored that for water potential changes including times when plant water status (soybean) was undergoing cyclical changes. PMID:16664805

  17. AGRICULTURAL DRAINAGE WELLS: IMPACT ON GROUND WATER

    EPA Science Inventory

    This document discusses agricultural drainage well practices, potential contamination problems that may occur, and possible management practices or regulatory solutions that could be used to alleviate those problems. The document has been written for use by state and Agency deci...

  18. 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.

  19. Continuous Crystallization of Urea-Water Mixture

    NASA Astrophysics Data System (ADS)

    Hokamura, Taku; Ohkubo, Hidetoshi; Watanabe, Satoshi; Seki, Mitsuo; Murakoshi, Hiromichi

    Ice slurries have been used as environmentally-friendly secondary refrigerants. In addition to such ice slurries, aqueous solutions in slurry-state have also been put to practical use at temperatures below 0 oC. Urea-water mixture is a multi-component substance that has a eutectic point. If we can form a two-phase fluid substance by the liquid-solid phases at the eutectic point, it can be used as a fluid latent heat storage material, which will maintain the secondary refrigerant in a heat exchanger at constant temperature. In the present study, we propose a urea-water mixture as a novel functional thermal fluid that can be used as a fluid latent heat material. To demonstrate its feasibility, we first measured the latent heat and density of a urea-water mixture, and then used a counter-flow double tube heat exchanger to produce a liquid-solid two-phase flow of the urea-water mixture. This work demonstrates that it is possible to make a fluid latent heat storage material continuously from an aqueous solution at the eutectic point by flowing it through a double tube heat exchanger equipped with a stirrer.

  20. 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.

  1. 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.

  2. Army industrial, landscaping, and agricultural water use

    SciTech Connect

    Stoughton, Kate McMordie; 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.

  3. Satellite Mapping of Agricultural Water Requirements in California

    NASA Astrophysics Data System (ADS)

    Melton, F. S.; Lund, C.; Johnson, L.; Guzman, A.; Hiatt, S.; Post, K.; Adhikari, D.; Rosevelt, C.; Keefauver, S.; Miller, G.; Michaelis, A.; Votava, P.; Temesgen, B.; Frame, K.; Nemani, R. R.

    2013-12-01

    Satellite mapping of evapotranspiration (ET) from irrigated agricultural lands can provide water managers and agricultural producers with information that can be used to optimize agricultural water use, especially in regions with limited water supplies. In particular, the timely delivery of information on agricultural crop water requirements has the potential to make irrigation scheduling more practical, convenient, and accurate. We present findings from the development and deployment of a prototype system for irrigation scheduling and management support in California. The Satellite Irrigation Management Support (SIMS) framework utilizes the NASA Terrestrial Observation and Prediction System to integrate satellite observations and meteorological observations from the California Irrigation Management Information System to map crop canopy development, basal crop coefficients (Kcb), and basal crop evapotranspiration (ETcb) values for multiple crop types in the Central Valley of California at the scale of individual fields. Information is distributed to agricultural producers and water managers via a web-based irrigation management decision support system and web services. We present the prototype system, including comparisons of estimates of ETcb from the prototype system against estimates of ET from other methods, including surface renewal stations and observations from wireless sensor networks deployed in operational agricultural fields across California. We also summarize results from ongoing studies to quantify the benefits of using satellite data to enhance ET-based irrigation management in terms of total applied water, crop yield, and nitrate leaching.

  4. Continuing education in physical rehabilitation and health issues of agricultural workers.

    PubMed

    Wilhite, Carla S; Jaco, Linda

    2014-01-01

    Limited attention has been devoted to the cultural and practice competencies needed by occupational therapy and physical therapy professionals who provide services to farming families impacted by chronic health or disability issues. Agricultural occupational safety and health should represent a continuum of services responsive to individuals, families, and agricultural communities across a life span and range of health status changes. Physical rehabilitation professionals have a key role in impacting an agricultural producer's sense of self-efficacy and capacities for returning to agricultural living and work. However, demonstration of competency is essential in providing person-centered rehabilitation services of assessment, evaluation, treatment planning, interventions, referrals, and discharge issues. The paper highlights methods utilized by a state AgrAbility program and a former National AgrAbility Project to develop a model of continuing education programming for occupational and physical therapists that evaluate and treat agricultural workers after acute injury or exacerbation of chronic health conditions.

  5. Substitutions between Water and other Agricultural Inputs - An Empirical Analysis

    NASA Astrophysics Data System (ADS)

    Cai, X.; You, J.

    2005-12-01

    Increasing concerns about water availability, environmental water requirement and water quality have led to an increased importance of quantitative assessments of the substitution between water and other agricultural inputs at the margin for agricultural and environmental policy analysis. This paper explores the potential substitutions between water and other agricultural inputs in irrigated agriculture through an empirical study. The study include (1) an analysis based on a crop production function for net substitution at the crop field and farm levels; and (2) a numerical study for gross substitution in the context of water allocation in river basins thorough an integrated hydrologic-economic river basin model. Along with the empirical analysis and numerical illustrations, we discuss several theoretical issues relevant to substitutions between water and other inputs, such as (1) selection of indicators of elasticity of substitution, depending on farmers' concerns on yield, production, or profit; (2) appropriateness of net or gross substitution analysis, which is relevant to the spatial scale of the analysis (field, district or region), as well as farmers' concerns; and (3) output impact of substitutions. Water is both a natural resource and an economic input, and the constraints on water include those from both physical and socio-economic aspects. Therefore, the output impact of the substitution between water and other inputs should be extended from a pure economic concept to the context of integrated hydrologic-economic systems.

  6. [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.

  7. Continuous water sampling and water analysis in estuaries

    USGS Publications Warehouse

    Schemel, L.E.; Dedini, L.A.

    1982-01-01

    Salinity, temperature, light transmission, oxygen saturation, pH, pCO2, chlorophyll a fluorescence, and the concentrations of nitrate, nitrite, dissolved silica, orthophosphate, and ammonia are continuously measured with a system designed primarily for estuarine studies. Near-surface water (2-m depth) is sampled continuously while the vessel is underway; on station, water to depths of 100 m is sampled with a submersible pump. The system is comprised of commercially available instruments, equipment, and components, and of specialized items designed and fabricated by the authors. Data are read from digital displays, analog strip-chart recorders, and a teletype printout, and can be logged in disc storage for subsequent plotting. Data records made in San Francisco Bay illustrate physical, biological, and chemical estuarine processes, such as mixing and phytoplankton net production. The system resolves large- and small-scale events, which contributes to its reliability and usefulness.

  8. Using continuous monitoring of physical parameters to better estimate phosphorus fluxes in a small agricultural catchment

    NASA Astrophysics Data System (ADS)

    Minaudo, Camille; Dupas, Rémi; Moatar, Florentina; Gascuel-Odoux, Chantal

    2016-04-01

    Phosphorus fluxes in streams are subjected to high temporal variations, questioning the relevance of the monitoring strategies (generally monthly sampling) chosen to assist EU Directives to capture phosphorus fluxes and their variations over time. The objective of this study was to estimate the annual and seasonal P flux uncertainties depending on several monitoring strategies, with varying sampling frequencies, but also taking into account simultaneous and continuous time-series of parameters such as turbidity, conductivity, groundwater level and precipitation. Total Phosphorus (TP), Soluble Reactive Phosphorus (SRP) and Total Suspended Solids (TSS) concentrations were surveyed at a fine temporal frequency between 2007 and 2015 at the outlet of a small agricultural catchment in Brittany (Naizin, 5 km2). Sampling occurred every 3 to 6 days between 2007 and 2012 and daily between 2013 and 2015. Additionally, 61 storms were intensively surveyed (1 sample every 30 minutes) since 2007. Besides, water discharge, turbidity, conductivity, groundwater level and precipitation were monitored on a sub-hourly basis. A strong temporal decoupling between SRP and particulate P (PP) was found (Dupas et al., 2015). The phosphorus-discharge relationships displayed two types of hysteretic patterns (clockwise and counterclockwise). For both cases, time-series of PP and SRP were estimated continuously for the whole period using an empirical model linking P concentrations with the hydrological and physic-chemical variables. The associated errors of the estimated P concentrations were also assessed. These « synthetic » PP and SRP time-series allowed us to discuss the most efficient monitoring strategies, first taking into account different sampling strategies based on Monte Carlo random simulations, and then adding the information from continuous data such as turbidity, conductivity and groundwater depth based on empirical modelling. Dupas et al., (2015, Distinct export dynamics for

  9. Using wetlands for water quality improvement in agricultural watersheds; the importance of a watershed scale approach.

    PubMed

    Crumpton, W G

    2001-01-01

    Agricultural applications of fertilizers and pesticides have increased dramatically since the middle 1960s, and agrochemical contamination of surface and groundwater has become a serious environmental concern. Since the mid-1980s, a variety of state and federal programs have been used to promote wetland restoration, and these continuing efforts provide a unique opportunity for water quality improvement in agricultural watersheds. However, wetland restorations have been motivated primarily by concern over waterfowl habitat loss, and model simulations suggest that commonly used site selection criteria for wetland restorations may be inadequate for water quality purposes. This does not lessen the promise of wetlands for water quality improvement in agricultural watersheds, but rather emphasizes the need for watershed scale approaches to wetland siting and design. Water quality is best viewed from a watershed perspective, and watershed scale endpoints should be explicitly considered in site selection for wetland restoration.

  10. 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...

  11. 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...

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. Water Resources and Sustainable Agriculture in 21st Century: Challenges and Opportunities

    NASA Astrophysics Data System (ADS)

    Asrar, G.

    2008-05-01

    Global agriculture faces some unique challenges and opportunities for the rest of this century. The need for food, feed and fiber will continues to grow as the world population continue to increase in the future. Agricultural ecosystems are also expected to be the source of a significant portion of renewable energy and fuels around the world, without further compromising the integrity of the natural resources base. How can agriculture continue to provide these services to meet the growing needs of world population while sustaining the integrity of agricultural ecosystems and natural resources, the very foundation it depends on? In the last century, scientific discoveries and technological innovations in agriculture resulted in significant increase in food, feed and fiber production globally, while the total amount of water, energy, fertilizers and other input used to achieve this growth remained the same or even decreased significantly in some parts of the world. Scientific and technical advances in understanding global and regional water and energy cycles, water resources management, soil and water conservation practices, weather prediction, plant breeding and biotechnology, and information and communication technologies contributed to this tremendous achievement. The projected increase in global population, urbanization, and changing lifestyles will continue the pressure on both agriculture and other managed and natural ecosystems to provide necessary goods and services for the rest of this century. To meet these challenges, we must obtain the requisite scientific and technical advances in the functioning of Earth's water, energy, carbon and biogeochemical cycles. We also need to apply the knowledge we gain and technologies we develop in assessing Earth's ecosystems' conditions, and their management and stewardship. In agricultural ecosystems, management of soil and water quality and quantity together with development of new varieties of plants based on advances

  17. 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.

  18. Comparison between agricultural and urban ground-water quality in the Mobile River Basin

    USGS Publications Warehouse

    Robinson, James L.

    2003-01-01

    The Black Warrior River aquifer is a major source of public water supply in the Mobile River Basin. The aquifer outcrop trends northwest - southeast across Mississippi and Alabama. A relatively thin shallow aquifer overlies and recharges the Black Warrior River aquifer in the flood plains and terraces of the Alabama, Coosa, Black Warrior, and Tallapoosa Rivers. Ground water in the shallow aquifer and the Black Warrior River aquifer is susceptible to contamination due to the effects of land use. Ground-water quality in the shallow aquifer and the shallow subcrop of the Black Warrior River aquifer, underlying an agricultural and an urban area, is described and compared. The agricultural and urban areas are located in central Alabama in Autauga, Elmore, Lowndes, Macon, Montgomery, and Tuscaloosa Counties. Row cropping in the Mobile River Basin is concentrated within the flood plains of major rivers and their tributaries, and has been practiced in some of the fields for nearly 100 years. Major crops are cotton, corn, and beans. Crop rotation and no-till planting are practiced, and a variety of crops are grown on about one-third of the farms. Row cropping is interspersed with pasture and forested areas. In 1997, the average farm size in the agricultural area ranged from 196 to 524 acres. The urban area is located in eastern Montgomery, Alabama, where residential and commercial development overlies the shallow aquifer and subcrop of the Black Warrior River aquifer. Development of the urban area began about 1965 and continued in some areas through 1995. The average home is built on a 1/8 - to 1/4 - acre lot. Ground-water samples were collected from 29 wells in the agricultural area, 30 wells in the urban area, and a reference well located in a predominately forested area. The median depth to the screens of the agricultural and urban wells was 22.5 and 29 feet, respectively. Ground-water samples were analyzed for physical properties, major ions, nutrients, and pesticides

  19. 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.

  20. Projections of Virtual Water Trade Under Agricultural Policy Scenarios in China

    NASA Astrophysics Data System (ADS)

    Dalin, C.; Hanasaki, N.; Qiu, H.; Mauzerall, D. L.; Rodriguez-Iturbe, I.

    2014-12-01

    China's economic growth is expected to continue into the next decades, accompanied by a sustained urbanization and industrialization. The associated increase in demand for land, water resources and rich foods will deepen the challenge to sustainably feed the population and balance environmental and agricultural policies. In previous work, Inner Mongolia was identified as a target province for trade or agricultural policies aimed at water-use efficiency improvements, due to its large production relying on particularly significant irrigation water use. In addition, water scarcity issues may arises in the greater Beijing area, which represents the largest urban area of arid Northern China. Increasing residential and industrial water demand in this region may lead to fewer available water for irrigation. For these reasons, it is important to estimate the impacts of specific policies aiming at reducing excessive water use for crop production in Inner Mongolia, as well as exploring ways to mitigate pressure on water resources in dry urban areas. In this study, we use socio-economic projections to assess the future state of China's virtual water trade (VWT) network. We then quantify the effects of agricultural policies on the national VWT system and on the efficiency of food trade in terms of water resources. This study addresses the following questions: (1) How future socio-economic changes will affect China's food trade and associated water transfers? (2) To which extent localized reductions of irrigated area can decrease agricultural water use while maintaining national food security? (3) How would these policies affect China's domestic and international VWT network and induced water resources savings (losses)?

  1. Climate Change and Water in Vulnerable Agriculture: Impacts - Mitigation - Adaptation

    NASA Astrophysics Data System (ADS)

    Dalezios, Nicolas; Tarquis, Ana Maria

    2016-04-01

    Agriculture highly depends on climate and is adversely affected by climate extremes caused mainly by anthropogenic climate change and increasing climate variability. Moreover, agricultural production risks and vulnerability of agriculture may become an issue in several regions around the world, since they are likely to increase the incidence of crop failure. The aim of this paper is to present the water availability and requirements in Southern Europe and specifically in the Mediterranean region, which is characterized by vulnerable agriculture. Indeed, the climatic trend in the 21st century for this region indicates temperature increase, precipitation decrease combined with an increase in the frequency of climate extremes, such as droughts, heat waves and forest fires. The three major components of climate change are examined, namely impacts, mitigation and adaptation. In particular, precipitation frequency analysis has already indicated a reduction in the precipitation amounts and a shift towards more intense rainstorms. Moreover, time series of drought indices are presented in affected areas. The importance of climate change mitigation measures is also highlighted. Finally, an adaptation scheme for agriculture from climate change in vulnerable and water scarce areas is presented.

  2. 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...

  3. Effective utilization of waste water through recycling, reuse, and remediation for sustainable agriculture.

    PubMed

    Raman, Rajamani; Krishnamoorthy, Renga

    2014-01-01

    Water is vital for human, animal, and plant life. Water is one of the most essential inputs for the production of crops. Plants need it in enormous quantities continuously during their life. The role of water is felt everywhere; its scarcity causes droughts and famines, its excess causes floods and deluge. During the next two decades, water will increasingly be considered a critical resource for the future survival of the arid and semiarid countries. The requirement of water is increasing day by day due to intensive agriculture practices, urbanization, population growth, industrialization, domestic use, and other uses. On the other hand, the availability of water resources is declining and the existing water is not enough to meet the needs. To overcome this problem, one available solution is utilization of waste water by using recycling, reuse, and remediation process.

  4. 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

    2016-07-14

    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.

  5. 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

  6. 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

  7. 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

  8. 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.

  9. 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.

  10. A complete and continuous pesticide screening during one growing season in five small Swiss rivers with agricultural watersheds

    NASA Astrophysics Data System (ADS)

    Mangold, Simon; Comte, Rahel; Doppler, Tobias; Wittmer, Irene; Moschet, Christoph; Stamm, Christian; Singer, Heinz; Kunz, Manuel

    2016-04-01

    Agricultural pesticides are regularly found in surface waters at concentration levels that raise ecotoxicological concerns. Due to large fluctuations in concentration over time and the potentially high number of pesticides in agricultural watersheds, it is difficult to obtain a comprehensive overview of the actual pollution level. This collaborative project between research and Swiss federal and cantonal authorities aimed for a comprehensive analysis of pesticide pollution in five small agricultural streams to address this knowledge gap. The five rivers are located in catchments (1.5 to 9 km2) with intensive agriculture covering a wide range of crops, such as grains, vegetables, vineyards and orchards. Urban activities and influences are low. Twelve-hour composite samples were collected continuously from March until the end of August with automatic sampling devices, resulting in 360 samples per site. Using precipitation and water level data, we differentiated between discharge events and low-flow periods. Samples taken during dry weather were pooled for the analysis. This procedure resulted in a complete concentration profile over the entire monitoring period covered by 60 samples per site. The analysis, using liquid chromatography coupled to high resolution mass spectrometry (Orbitrap technology), involved a target screening of 248 pesticides including fungicides, herbicides, insecticides, as well as important transformation products. Data on the total number and distribution of pesticides, their detection frequency, crop specific applications and concentration time profiles will be presented. Preliminary results indicate substantial pesticide exposure since at least 20 different compounds were detected in all samples. One sample even contained a mixture of 80 pesticides. The majority of concentrations were in the low ng/L range but concentrations of a few compounds were very high (several micrograms/L) during discharge events as well as during low flow conditions

  11. 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.

  12. Evaluating sustainable water quality management in the U.S.: Urban, Agricultural, and Environmental Protection Practices

    NASA Astrophysics Data System (ADS)

    van Oel, P. R.; Alfredo, K. A.; Russo, T. A.

    2015-12-01

    Sustainable water management typically emphasizes water resource quantity, with focus directed at availability and use practices. When attention is placed on sustainable water quality management, the holistic, cross-sector perspective inherent to sustainability is often lost. Proper water quality management is a critical component of sustainable development practices. However, sustainable development definitions and metrics related to water quality resilience and management are often not well defined; water quality is often buried in large indicator sets used for analysis, and the policy regulating management practices create sector specific burdens for ensuring adequate water quality. In this research, we investigated the methods by which water quality is evaluated through internationally applied indicators and incorporated into the larger idea of "sustainability." We also dissect policy's role in the distribution of responsibility with regard to water quality management in the United States through evaluation of three broad sectors: urban, agriculture, and environmental water quality. Our research concludes that despite a growing intention to use a single system approach for urban, agricultural, and environmental water quality management, one does not yet exist and is even hindered by our current policies and regulations. As policy continues to lead in determining water quality and defining contamination limits, new regulation must reconcile the disparity in requirements for the contaminators and those performing end-of-pipe treatment. Just as the sustainable development indicators we researched tried to integrate environmental, economic, and social aspects without skewing focus to one of these three categories, policy cannot continue to regulate a single sector of society without considering impacts to the entire watershed and/or region. Unequal distribution of the water pollution burden creates disjointed economic growth, infrastructure development, and policy

  13. Evaluation for sustainable agriculture water use from River, Reservoirs and Groundwater in the 20th century

    NASA Astrophysics Data System (ADS)

    Yoshikawa, S.; Yamada, H.; Hanasaki, N.; Kanae, S.

    2011-12-01

    High water stress due to economic growth and climate change (ex. global warming) will be falling into 2 billion people to 4 billion people in the future. Agricultural water use accounting for about 70% of global water consumption might continue to increase due to production of foods and biofuels occurred by population growth in the future. In particular, water demand, food and biofuel production have an inextricable link. It is very important to evaluate these relationship for sustainable water use from past to the future. In this study, we focused on the objective to assess the impact of water withdrawal from various sources (stream flow, medium-sized reservoirs and nonrenewable nonlocal blue water) in the 20th century by considering irrigation area and climate change. Irrigation water withdrawal is the most important water use sector accounting for about 90% of total water withdrawal. First, we make the global spatial database of equipped irrigation area change and medium-sized reservoirs capacity. Then, water withdrawal from each sources for 50 years from 1950 to 2000 were simulated in global-scale at a resolution of 1.0 degree x 1.0 degree using an integrated global water resources model (hereafter, the H08 model). The H08 model can simulate both natural or anthropogenic water flow and anthropogenic water withdrawals. For comparison with our results, distribution of agricultural, industrial and domestic water withdrawals from 1950 to 2000 were estimated by distributing the country-based withdrawal data from AQUASTAT with irrigation area, urban population and total population, respectively. Groundwater withdrawal was then estimated by distributing the country-based withdrawal data based on statistical data from WRI, IGRAC and AQUASTAT with the total water withdrawal. As a result, agricultural water withdrawal change from nonrenewable nonlocal blue water during the past 50 years agreed well with the observed groundwater abstraction based on statistical data. In

  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. 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.

  16. 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

  17. 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

  18. 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...

  19. A Need for Education in Water Sustainability in the Agricultural Realm

    NASA Astrophysics Data System (ADS)

    Krajewski, J.

    2015-12-01

    This study draws upon the definition of water sustainability from the National Water Research Institute as the continual supply of clean water for human uses and for other living beings without compromising the water welfare of future generations. Currently, the greatest consumer of water resources worldwide is irrigation. The move from small-scale, family farms towards corporately owned and market driven, mass scale operations have drastically increased corn production and large-scale factory hog farming in the American Midwest—and the water quality related costs associated with this shift are well-documented. In the heart of the corn belt, the state of Iowa has dealt with issues over the past two decades ranging from flooding of historic proportions, to yield destroying droughts. Most recently, the state's water quality is intensely scrutinized due to nutrient levels higher than almost anywhere else in the world. While the changed agricultural landscape is ultimately responsible for these environmental costs, they can be mitigated if the farmers adopt practices that support water sustainability. However, many Iowa farmers have yet to embrace these necessary practices because of a lack of proper education in this context. Thus, the purpose of this paper is to explore how water sustainability is being conceptualized within the agricultural realm, and ultimately, how the issues are being communicated and understood within various subgroups in Iowa, such as the farmers, the college students, and the general public.

  20. Study of continuous-wave domain fluorescence diffuse optical tomography for quality control on agricultural produce

    NASA Astrophysics Data System (ADS)

    Nadhira, Vebi; Kurniadi, Deddy; Juliastuti, E.; Sutiswan, Adeline

    2014-03-01

    The importance of monitoring the quality of vegetables and fruits is prosperity by giving a competitive advantage for producer and providing a more healthy food for consumer. Diffuse Optical Tomography (DOT) is offering the possibility to detect the internal defects of the agricultural produce quality. Fluorescence diffuse optical tomography (FDOT) is the development of DOT, offering the possibilities to improve spatial resolution and to contrast image. The purpose of this research is to compare FDOT and DOT in forward analysis with continuous wave approach. The scattering and absorbing parameters of potatoes are used to represent the real condition. The object was illuminated by the NIR source from some positions on the boundary of object. A set of NIR detector are placed on the peripheral position of the object to measure the intensity of propagated or emitted light. In the simulation, we varied a condition of object then we analyzed the sensitivity of forward problem. The result of this study shows that FDOT has a better sensitivity than DOT and a better potential to monitor internal defects of agricultural produce because of the contrast value between optical and fluorescence properties of agricultural produce normal tissue and defects.

  1. Study of continuous-wave domain fluorescence diffuse optical tomography for quality control on agricultural produce

    SciTech Connect

    Nadhira, Vebi Kurniadi, Deddy Juliastuti, E. Sutiswan, Adeline

    2014-03-24

    The importance of monitoring the quality of vegetables and fruits is prosperity by giving a competitive advantage for producer and providing a more healthy food for consumer. Diffuse Optical Tomography (DOT) is offering the possibility to detect the internal defects of the agricultural produce quality. Fluorescence diffuse optical tomography (FDOT) is the development of DOT, offering the possibilities to improve spatial resolution and to contrast image. The purpose of this research is to compare FDOT and DOT in forward analysis with continuous wave approach. The scattering and absorbing parameters of potatoes are used to represent the real condition. The object was illuminated by the NIR source from some positions on the boundary of object. A set of NIR detector are placed on the peripheral position of the object to measure the intensity of propagated or emitted light. In the simulation, we varied a condition of object then we analyzed the sensitivity of forward problem. The result of this study shows that FDOT has a better sensitivity than DOT and a better potential to monitor internal defects of agricultural produce because of the contrast value between optical and fluorescence properties of agricultural produce normal tissue and defects.

  2. Managing ground-water contamination from agricultural nitrates

    SciTech Connect

    Halstead, J.M.

    1989-01-01

    Ground-water contamination from agricultural nitrates poses potential adverse health effects to a large segment of the rural population of the United States. Contamination is especially prevalent in livestock intensive areas, which produce large quantities of animal waste with substantial nitrogen content. In this study, potential management strategies for reducing nitrate contamination of ground water from agricultural sources were examined using an economic-physical model of representative dairy farm in Rockingham County, Virginia. A mixed-integer programming model with stochastic constraints on nitrate loading to ground water and silage production was used. Results of the model indicate that substantial reductions in current nitrate loadings are possible with relatively minor impacts on farmers' net returns through the use of currently practiced approaches of cost sharing for manure storage facility construction and nutrient management planning. Study results indicate that a wide range of policy options exist for reducing nitrate loading to ground water; these reductions, while varying in cost, do no appear to come at the expense of eliminating the economic viability of the county dairy sector.

  3. Agricultural Diversification and Marketing. Instructional Materials Developed for Secondary, Postsecondary, and Continuing Education Agriculture Programs in Iowa.

    ERIC Educational Resources Information Center

    Iowa State Dept. of Agriculture, Des Moines.

    These instructional materials on agricultural diversification and marketing were developed for use by Iowa's vocational and technical agricultural instructors and extension personnel. This document is one of three manuals making up a single package. (The other two are Christmas Tree Production and Marketing and Sod Production and Marketing). The…

  4. Carbon and Phosphorus in soil particulate fraction: effect of continuous agriculture, tillage and fertilization

    NASA Astrophysics Data System (ADS)

    Wyngaard, N.; Echeverrıa, H. E.; Vidaurreta, A.; Picone, L. I.; Divito, G. A.

    2012-04-01

    In Argentinean Pampas region, the practice of intensive agriculture has diminished total organic carbon (TOC) content in soil. This degradation process can impact over phosphorus (P) organic fractions associated to it, and therefore limit soil capacity to provide P through mineralization. Along this line, P content in soil particulate fraction (PF) has been proposed as an index to estimate this capacity. The aims of this work were to evaluate (1) the effect of continuous agriculture, tillage and P fertilization over TOC and P fractions content in soil and PF, and (2) the stability of P-PF as a mineralization index. To this end, a long term experiment initiated in 2001 in Balcarce, Argentina, under continuous agriculture, was analyzed. There, two tillage systems - conventional till (CT) and no till (NT) - and two fertilization treatments - nitrogen (N) and N + P (NP) - were evaluated. Phosphorus rate was 30 kg ha-1 year-1. In each plot, the following parameters were determined in 2002, 2005, 2008 and 2011: TOC, P Bray, total P (Pt), inorganic P (Pi), and organic P (Po) content in the whole soil and in the PF. Also, C supply by residues and P soil balance during the experiment were calculated, and the P sorption capacity was determined in samples from 2011. C supply was greater in CT (7% relative to NT) and in NP (14% relative to N). However, TOC in soil was not modified neither by tillage or fertilization. Even though, C in the PF decreased (3% annually) by the use of continuous agriculture. This reduction was positively associated to the one observed in other soil properties as Pt, Pi and Po in the PF. P fertilization lessened this reduction in Pt (18,9 mg kg-1 in N and 23,1 mg kg-1 in NP in 2011) and Pi (4,2 mg kg-1 in N and 6,2 mg kg-1 in NP in 2011), but not in Po. This indicates that, Po is affected by management practices and, contrary to Pt, is stable to fertilization. Therefore Po can be studied as a potential P mineralization index. The difference among P

  5. 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

  6. 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.

  7. Evaluation of Linear Alkylbenzene Sulfonate (LAS) behaviour in agricultural soil through laboratory continuous studies.

    PubMed

    Oliver-Rodríguez, B; Zafra-Gómez, A; Reis, M S; Duarte, B P M; Verge, C; de Ferrer, J A; Pérez-Pascual, M; Vílchez, J L

    2015-07-01

    The behaviour of Linear Alkylbenzene Sulfonate (LAS) in agricultural soil is investigated in the laboratory using continuous-flow soil column studies in order to simultaneously analyze the three main underlying phenomena (adsorption/desorption, degradation and transport). The continuous-flow soil column experiments generated the breakthrough curves for each LAS homologue, C10, C11, C12 and C13, and by adding them up, for total LAS, from which the relevant retention, degradation and transport parameters could be estimated, after proposing adequate models. Several transport equations were considered, including the degradation of the sorbate in solution and its retention by soil, under equilibrium and non-equilibrium conditions between the sorbent and the sorbate. In general, the results obtained for the estimates of those parameters that were common to the various models studied (such as the isotherm slope, first order degradation rate coefficient and the hydrodynamic dispersion coefficient) were rather consistent, meaning that mass transfer limitations are not playing a major role in the experiments. These three parameters increase with the length of the LAS homologue chain. The study will provide the underlying conceptual framework and fundamental parameters to understand, simulate and predict the environmental behaviour of LAS compounds in agricultural soils. PMID:25765258

  8. Evaluation of Linear Alkylbenzene Sulfonate (LAS) behaviour in agricultural soil through laboratory continuous studies.

    PubMed

    Oliver-Rodríguez, B; Zafra-Gómez, A; Reis, M S; Duarte, B P M; Verge, C; de Ferrer, J A; Pérez-Pascual, M; Vílchez, J L

    2015-07-01

    The behaviour of Linear Alkylbenzene Sulfonate (LAS) in agricultural soil is investigated in the laboratory using continuous-flow soil column studies in order to simultaneously analyze the three main underlying phenomena (adsorption/desorption, degradation and transport). The continuous-flow soil column experiments generated the breakthrough curves for each LAS homologue, C10, C11, C12 and C13, and by adding them up, for total LAS, from which the relevant retention, degradation and transport parameters could be estimated, after proposing adequate models. Several transport equations were considered, including the degradation of the sorbate in solution and its retention by soil, under equilibrium and non-equilibrium conditions between the sorbent and the sorbate. In general, the results obtained for the estimates of those parameters that were common to the various models studied (such as the isotherm slope, first order degradation rate coefficient and the hydrodynamic dispersion coefficient) were rather consistent, meaning that mass transfer limitations are not playing a major role in the experiments. These three parameters increase with the length of the LAS homologue chain. The study will provide the underlying conceptual framework and fundamental parameters to understand, simulate and predict the environmental behaviour of LAS compounds in agricultural soils.

  9. 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.

  10. Soil water and carbon management for agricultural resilience in a key node in the global virtual water trade network: Mato Grosso, Brazil

    NASA Astrophysics Data System (ADS)

    Johnson, M. S.; Speratti, A. B.; Lathuilliere, M. J.; Dalmagro, H. J.; Couto, E. G.

    2015-12-01

    The Amazon region is globally connected through agricultural exports, with the Brazilian state of Mato Grosso in particular emerging as a key node in the global virtual water trade network in recent years, based largely on rainfed agriculture. The anticipated growth in the world's population suggests that virtual water trade will only become more important to global food security. In this presentation we will evaluate strategies for improving the resilience of rainfed agriculture in the region, particularly for the nearly 12 million hectares of sandy soil with low water holding capacity within Mato Grosso that has largely been converted to agricultural use. We will review land use change trajectories and present results from soil water balance modeling and carbon fluxes for a range of future scenarios, including continued agricultural extensification, potential strategies for agricultural intensification, and novel water and carbon management strategies including biochar use in sandy soils to improve soil water holding capacities and soil carbon sequestration. We will also consider the role that irrigation might play in the future in the Amazon for improving agricultural resilience to climate change and feedbacks between irrigation and land use change pressures, noting that groundwater resources in the region are presently among the least exploited on the planet.

  11. 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...

  12. 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.

  13. 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.

  14. 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.

  15. Continuous real-time water information: an important Kansas resource

    USGS Publications Warehouse

    Loving, Brian L.; Putnam, James E.; Turk, Donita M.

    2014-01-01

    Continuous real-time information on streams, lakes, and groundwater is an important Kansas resource that can safeguard lives and property, and ensure adequate water resources for a healthy State economy. The U.S. Geological Survey (USGS) operates approximately 230 water-monitoring stations at Kansas streams, lakes, and groundwater sites. Most of these stations are funded cooperatively in partnerships with local, tribal, State, or other Federal agencies. The USGS real-time water-monitoring network provides long-term, accurate, and objective information that meets the needs of many customers. Whether the customer is a water-management or water-quality agency, an emergency planner, a power or navigational official, a farmer, a canoeist, or a fisherman, all can benefit from the continuous real-time water information gathered by the USGS.

  16. 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.

  17. 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.

  18. Land-use change affects water recycling in Brazil's last agricultural frontier.

    PubMed

    Spera, Stephanie A; Galford, Gillian L; Coe, Michael T; Macedo, Marcia N; Mustard, John F

    2016-10-01

    Historically, conservation-oriented research and policy in Brazil have focused on Amazon deforestation, but a majority of Brazil's deforestation and agricultural expansion has occurred in the neighboring Cerrado biome, a biodiversity hotspot comprised of dry forests, woodland savannas, and grasslands. Resilience of rainfed agriculture in both biomes likely depends on water recycling in undisturbed Cerrado vegetation; yet little is known about how changes in land-use and land-cover affect regional climate feedbacks in the Cerrado. We used remote sensing techniques to map land-use change across the Cerrado from 2003 to 2013. During this period, cropland agriculture more than doubled in area from 1.2 to 2.5 million ha, with 74% of new croplands sourced from previously intact Cerrado vegetation. We find that these changes have decreased the amount of water recycled to the atmosphere via evapotranspiration (ET) each year. In 2013 alone, cropland areas recycled 14 km(3) less (-3%) water than if the land cover had been native Cerrado vegetation. ET from single-cropping systems (e.g., soybeans) is less than from natural vegetation in all years, except in the months of January and February, the height of the growing season. In double-cropping systems (e.g., soybeans followed by corn), ET is similar to or greater than natural vegetation throughout a majority of the wet season (December-May). As intensification and extensification of agricultural production continue in the region, the impacts on the water cycle and opportunities for mitigation warrant consideration. For example, if an environmental goal is to minimize impacts on the water cycle, double cropping (intensification) might be emphasized over extensification to maintain a landscape that behaves more akin to the natural system. PMID:27028754

  19. Land-use change affects water recycling in Brazil's last agricultural frontier.

    PubMed

    Spera, Stephanie A; Galford, Gillian L; Coe, Michael T; Macedo, Marcia N; Mustard, John F

    2016-10-01

    Historically, conservation-oriented research and policy in Brazil have focused on Amazon deforestation, but a majority of Brazil's deforestation and agricultural expansion has occurred in the neighboring Cerrado biome, a biodiversity hotspot comprised of dry forests, woodland savannas, and grasslands. Resilience of rainfed agriculture in both biomes likely depends on water recycling in undisturbed Cerrado vegetation; yet little is known about how changes in land-use and land-cover affect regional climate feedbacks in the Cerrado. We used remote sensing techniques to map land-use change across the Cerrado from 2003 to 2013. During this period, cropland agriculture more than doubled in area from 1.2 to 2.5 million ha, with 74% of new croplands sourced from previously intact Cerrado vegetation. We find that these changes have decreased the amount of water recycled to the atmosphere via evapotranspiration (ET) each year. In 2013 alone, cropland areas recycled 14 km(3) less (-3%) water than if the land cover had been native Cerrado vegetation. ET from single-cropping systems (e.g., soybeans) is less than from natural vegetation in all years, except in the months of January and February, the height of the growing season. In double-cropping systems (e.g., soybeans followed by corn), ET is similar to or greater than natural vegetation throughout a majority of the wet season (December-May). As intensification and extensification of agricultural production continue in the region, the impacts on the water cycle and opportunities for mitigation warrant consideration. For example, if an environmental goal is to minimize impacts on the water cycle, double cropping (intensification) might be emphasized over extensification to maintain a landscape that behaves more akin to the natural system.

  20. 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.

  1. 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

  2. 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

  3. Agricultural phosphorus, water quality, and poultry production: are they compatible?

    PubMed

    Sharpley, A

    1999-05-01

    With the concentration of poultry production and increase in operation size in several regions of the U.S., more manure is applied to agricultural land. This application of manure has resulted in more P being added than crops require, an accumulation in soil P, and increased potential for P loss in surface runoff. This situation has been exacerbated by manure management being N-based. Increased outputs of P to fresh waters can accelerate eutrophication, which impairs water use and can lead to fish kills and toxic algal blooms. As a result, information is needed on the effect of poultry production on the fate of P in agricultural systems so that compatible production and water quality goals can be met. Overall, these goals will be met by focusing on ways to increase P use-efficiency by attempting to balance inputs of P in feed and fertilizer into a watershed with output in crop and livestock. This will involve refining feed rations, using feed additives to increase P absorption by the animal, moving manure from surplus to deficit areas, finding alternative uses for manure, and targeting conservation practices, such as reduced tillage, buffer strips, and cover crops, to critical areas of P export from a watershed. These critical areas are where high P soils coincide with parts of the landscape where surface runoff and erosion potential is high. Development of management systems that address both production and environmental concerns must consider the socioeconomic and political impacts of any management changes on both rural and urban communities, and of the mechanisms by which change can be achieved in a diverse and dispersed community of land users. PMID:10228962

  4. 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.

  5. 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

  6. 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

  7. 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.

  8. 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

  9. 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.

  10. Key to GHG fluxes from organic soils: site characteristics, agricultural practices or water table management?

    NASA Astrophysics Data System (ADS)

    Tiemeyer, Bärbel

    2015-04-01

    Drained peatlands are hotspots of greenhouse gas (GHG) emissions. Agriculture is the major land use type for peatlands in Germany and other European countries, but strongly varies in its intensity regarding the groundwater level and the agricultural management. Although the mean annual water table depth is sometimes proposed as an overall predictor for GHG emissions, there is a strong variability of its effects on different peatlands. Furthermore, re-wetting measures generally decrease carbon dioxide emissions, but may strongly increase methane emissions. We synthesized 250 annual GHG budgets for 120 different sites in 13 German peatlands. Carbon dioxide (net ecosystem exchange and ecosystem respiration), nitrous oxide and methane fluxes were measured with transparent and opaque manual chambers. Land management ranged from very intensive use with arable land or grassland with up to five cuts per year to partially or completely re-wetted peatlands. Besides the GHG fluxes, biomass yield, fertilisation, groundwater level, climatic data, vegetation composition and soil properties were measured. Overall, we found a large variability of the total GHG budget ranging from small uptakes to extremely high emissions (> 70 t CO2-equivalents/(ha yr)). At nearly all sites, carbon dioxide was the major component of the GHG budget. Site conditions, especially the nitrogen content of the unsaturated zone and the intra-annual water level distribution, controlled the GHG emissions of the agricultural sites. Although these factors are influenced by natural conditions (peat type, regional hydrology), they could be modified by an improved water management. Agricultural management such as the number of cuts had only a minor influence on the GHG budgets. At the level of individual peatlands, higher water levels always decreased carbon dioxide emissions. In nearly all cases, the trade-off between reduced carbon dioxide and increased methane emissions turned out in favour of the re

  11. 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.

  12. 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...

  13. Continuous melting through a hexatic phase in confined bilayer water.

    PubMed

    Zubeltzu, Jon; Corsetti, Fabiano; Fernández-Serra, M V; Artacho, Emilio

    2016-06-01

    Liquid water is not only of obvious importance but also extremely intriguing, displaying many anomalies that still challenge our understanding of such an a priori simple system. The same is true when looking at nanoconfined water: The liquid between constituents in a cell is confined to such dimensions, and there is already evidence that such water can behave very differently from its bulk counterpart. A striking finding has been reported from computer simulations for two-dimensionally confined water: The liquid displays continuous or discontinuous melting depending on its density. In order to understand this behavior, we have analyzed the melting exhibited by a bilayer of nanoconfined water by means of molecular dynamics simulations. At high density we observe the continuous melting to be related to the phase change of the oxygens only, with the hydrogens remaining liquidlike throughout. Moreover, we find an intermediate hexatic phase for the oxygens between the liquid and a triangular solid ice phase, following the Kosterlitz-Thouless-Halperin-Nelson-Young theory for two-dimensional melting. The liquid itself tends to maintain the local structure of the triangular ice, with its two layers being strongly correlated yet with very slow exchange of matter. The decoupling in the behavior of the oxygens and hydrogens gives rise to a regime in which the complexity of water seems to disappear, resulting in what resembles a simple monoatomic liquid. This intrinsic tendency of our simulated water may be useful for understanding novel behaviors in other confined and interfacial water systems. PMID:27415238

  14. Continuous melting through a hexatic phase in confined bilayer water

    NASA Astrophysics Data System (ADS)

    Zubeltzu, Jon; Corsetti, Fabiano; Fernández-Serra, M. V.; Artacho, Emilio

    2016-06-01

    Liquid water is not only of obvious importance but also extremely intriguing, displaying many anomalies that still challenge our understanding of such an a priori simple system. The same is true when looking at nanoconfined water: The liquid between constituents in a cell is confined to such dimensions, and there is already evidence that such water can behave very differently from its bulk counterpart. A striking finding has been reported from computer simulations for two-dimensionally confined water: The liquid displays continuous or discontinuous melting depending on its density. In order to understand this behavior, we have analyzed the melting exhibited by a bilayer of nanoconfined water by means of molecular dynamics simulations. At high density we observe the continuous melting to be related to the phase change of the oxygens only, with the hydrogens remaining liquidlike throughout. Moreover, we find an intermediate hexatic phase for the oxygens between the liquid and a triangular solid ice phase, following the Kosterlitz-Thouless-Halperin-Nelson-Young theory for two-dimensional melting. The liquid itself tends to maintain the local structure of the triangular ice, with its two layers being strongly correlated yet with very slow exchange of matter. The decoupling in the behavior of the oxygens and hydrogens gives rise to a regime in which the complexity of water seems to disappear, resulting in what resembles a simple monoatomic liquid. This intrinsic tendency of our simulated water may be useful for understanding novel behaviors in other confined and interfacial water systems.

  15. 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

  16. 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

  17. Ancient lipids reveal continuity in culinary practices across the transition to agriculture in Northern Europe

    PubMed Central

    Craig, Oliver E.; Steele, Val J.; Fischer, Anders; Hartz, Sönke; Andersen, Søren H.; Donohoe, Paul; Glykou, Aikaterini; Saul, Hayley; Jones, D. Martin; Koch, Eva; Heron, Carl P.

    2011-01-01

    Farming transformed societies globally. Yet, despite more than a century of research, there is little consensus on the speed or completeness of this fundamental change and, consequently, on its principal drivers. For Northern Europe, the debate has often centered on the rich archaeological record of the Western Baltic, but even here it is unclear how quickly or completely people abandoned wild terrestrial and marine resources after the introduction of domesticated plants and animals at ∼4000 calibrated years B.C. Ceramic containers are found ubiquitously on these sites and contain remarkably well-preserved lipids derived from the original use of the vessel. Reconstructing culinary practices from this ceramic record can contribute to longstanding debates concerning the origins of farming. Here we present data on the molecular and isotopic characteristics of lipids extracted from 133 ceramic vessels and 100 carbonized surface residues dating to immediately before and after the first evidence of domesticated animals and plants in the Western Baltic. The presence of specific lipid biomarkers, notably ω-(o-alkylphenyl)alkanoic acids, and the isotopic composition of individual n-alkanoic acids clearly show that a significant proportion (∼20%) of ceramic vessels with lipids preserved continued to be used for processing marine and freshwater resources across the transition to agriculture in this region. Although changes in pottery use are immediately evident, our data challenge the popular notions that economies were completely transformed with the arrival of farming and that Neolithic pottery was exclusively associated with produce from domesticated animals and plants. PMID:22025697

  18. 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.

  19. 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

  20. Comparing microbial water quality in an intermittent and continuous piped water supply.

    PubMed

    Kumpel, Emily; Nelson, Kara L

    2013-09-15

    Supplying piped water intermittently is a common practice throughout the world that increases the risk of microbial contamination through multiple mechanisms. Converting an intermittent supply to a continuous supply has the potential to improve the quality of water delivered to consumers. To understand the effects of this upgrade on water quality, we tested samples from reservoirs, consumer taps, and drinking water provided by households (e.g. from storage containers) from an intermittent and continuous supply in Hubli-Dharwad, India, over one year. Water samples were tested for total coliform, Escherichia coli, turbidity, free chlorine, and combined chlorine. While water quality was similar at service reservoirs supplying the continuous and intermittent sections of the network, indicator bacteria were detected more frequently and at higher concentrations in samples from taps supplied intermittently compared to those supplied continuously (p < 0.01). Detection of E. coli was rare in continuous supply, with 0.7% of tap samples positive compared to 31.7% of intermittent water supply tap samples positive for E. coli. In samples from both continuously and intermittently supplied taps, higher concentrations of total coliform were measured after rainfall events. While source water quality declined slightly during the rainy season, only tap water from intermittent supply had significantly more indicator bacteria throughout the rainy season compared to the dry season. Drinking water samples provided by households in both continuous and intermittent supplies had higher concentrations of indicator bacteria than samples collected directly from taps. Most households with continuous supply continued to store water for drinking, resulting in re-contamination, which may reduce the benefits to water quality of converting to continuous supply.

  1. Alternative agriculture adoption: Effects of ground water contamination and other factors

    SciTech Connect

    Cyphers, D.; D'Souza, G. )

    1992-12-01

    The factors influencing adoption of alternative agriculture are quantified using a logit model and survey data. The likelihood of adoption of alternative agriculture is affected most by the environmental characteristic of whether or not ground water contamination exists. This creates an awareness effect' upon which to formulate policies leading to a sustainable agriculture.

  2. 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...

  3. [Research on the virtual water composition and virtual water trade for agriculture in Beijing].

    PubMed

    Wang, Hong-rui; Wang, Yan; Wang, Jun-hong; Dong, Yan-yan; Han, Zhao-xing

    2007-12-01

    Based on the irrigation norm of typical district and county, and revised by the isoline map of Chinese crops water demand, the change of crops program was analyzed as well as the agricultural water use and its GDP benefits. Then the virtual water was calculated for years. At last, the input-output method was used to calculate the trade of virtual water in Beijing. As the results, the virtual water for cereal crops has been decreasing in Beijing, from 1.832 x 10(9) m3 in 1990 to 4.283 x 10(8) m3 in 2004. Otherwise the virtual water for technical crops has been increasing, which is from 9.06 x 10(8) m3 in 1990 to 1.492 x 10(9) m3 in 2004. On the whole, the virtual water for crops has been decreasing in Beijing. From the angle of primary products Beijing is a virtual water importing area. Virtual water importing of annual average is 2.37 x 10(8) m3, which is about 5.93% of the total water of Beijing. Virtual water has been an important supplement of local real water of Beijing.

  4. Batch vs continuous-feeding operational mode for the removal of pesticides from agricultural run-off by microalgae systems: A laboratory scale study.

    PubMed

    Matamoros, Víctor; Rodríguez, Yolanda

    2016-05-15

    Microalgae-based water treatment technologies have been used in recent years to treat different water effluents, but their effectiveness for removing pesticides from agricultural run-off has not yet been addressed. This paper assesses the effect of microalgae in pesticide removal, as well as the influence of different operation strategies (continuous vs batch feeding). The following pesticides were studied: mecoprop, atrazine, simazine, diazinone, alachlor, chlorfenvinphos, lindane, malathion, pentachlorobenzene, chlorpyrifos, endosulfan and clofibric acid (tracer). 2L batch reactors and 5L continuous reactors were spiked to 10 μg L(-1) of each pesticide. Additionally, three different hydraulic retention times (HRTs) were assessed (2, 4 and 8 days) in the continuous feeding reactors. The batch-feeding experiments demonstrated that the presence of microalgae increased the efficiency of lindane, alachlor and chlorpyrifos by 50%. The continuous feeding reactors had higher removal efficiencies than the batch reactors for pentachlorobenzene, chlorpyrifos and lindane. Whilst longer HRTs increased the technology's effectiveness, a low HRT of 2 days was capable of removing malathion, pentachlorobenzene, chlorpyrifos, and endosulfan by up to 70%. This study suggests that microalgae-based treatment technologies can be an effective alternative for removing pesticides from agricultural run-off.

  5. 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)

  6. Agricultural green and blue water consumption and its influence on the global water system

    NASA Astrophysics Data System (ADS)

    Rost, Stefanie; Gerten, Dieter; Bondeau, Alberte; Lucht, Wolfgang; Rohwer, Janine; Schaphoff, Sibyll

    2008-09-01

    This study quantifies, spatially explicitly and in a consistent modeling framework (Lund-Potsdam-Jena managed Land), the global consumption of both "blue" water (withdrawn for irrigation from rivers, lakes and aquifers) and "green" water (precipitation) by rainfed and irrigated agriculture and by nonagricultural terrestrial ecosystems. In addition, the individual effects of human-induced land cover change and irrigation were quantified to assess the overall hydrological impact of global agriculture in the past century. The contributions to irrigation of nonrenewable (fossil groundwater) and nonlocal blue water (e.g., from diverted rivers) were derived from the difference between a simulation in which these resources were implicitly considered (IPOT) and a simulation in which they were neglected (ILIM). We found that global cropland consumed >7200 km3 year-1 of green water in 1971-2000, representing 92% (ILIM) and 85% (IPOT), respectively, of total crop water consumption. Even on irrigated cropland, 35% (ILIM) and 20% (IPOT) of water consumption consisted of green water. An additional 8155 km3 year-1 of green water was consumed on grazing land; a further ˜44,700 km3 year-1 sustained the ecosystems. Blue water consumption predominated only in intensively irrigated regions and was estimated at 636 km3 year-1 (ILIM) and 1364 km3 year-1 (IPOT) globally, suggesting that presently almost half of the irrigation water stemmed from nonrenewable and nonlocal sources. Land cover conversion reduced global evapotranspiration by 2.8% and increased discharge by 5.0% (1764 km3 year-1), whereas irrigation increased evapotranspiration by up to 1.9% and decreased discharge by 0.5% at least (IPOT, 1971-2000). The diverse water fluxes displayed considerable interannual and interdecadal variability due to climatic variations and the progressive increase of the global area under cultivation and irrigation.

  7. Analysis of the Continuing Decline in Use of Supervised Agricultural Experience (SAE) in New York State.

    ERIC Educational Resources Information Center

    Steele, Roger

    1997-01-01

    When responses from 135 of 222 New York secondary agriculture teachers were compared with a 1983 study, a 10% decrease in supervised agricultural experience (SAE) was found. Barriers were low level of summer employment, limited release time, less funding for transportation, and scheduling problems. A comprehensive overhaul of the concept and…

  8. Climate Risks on Water and Agriculture in the Indus Basin of Pakistan

    NASA Astrophysics Data System (ADS)

    Yang, Y. E.; Brown, C. M.; Yu, W.

    2012-12-01

    Pakistan relies on the largest contiguous irrigation system in the world, known as the Indus Basin Irrigation System (IBIS) for its basic food security and water supply for all sectors of the economy. The basin that supports this irrigation system consists of the Indus River mainsteam and its major tributaries. The integrated systems framework used in this analysis provides a broad and unique approach to estimating the hydrologic and crop impacts of climate change risks, the macro-economic and household-level responses and an effective method for assessing a variety of adaptation investments and policies. In assessing the impacts, several different modeling environments must be integrated to provide a more nuanced and complete picture of how water and agriculture inter-relate. Moreover, such a framework allows for extensive scenario analysis to identify and understand key sensitivities. This is critical to making decisions in a highly uncertain future. Finally, through this integration of multiple disciplines, a richer and more robust set of adaptation investment options and policies for the agriculture and water sectors can be identified and tested. Continued refinements to the assessment approach developed in this volume will further help to sharpen critical policies and interventions by the Pakistan government. Fig 2. Impacts of climate change on GDP, Ag-GDP and Household income in the Indus Basin Fig1. The Indus River Basin

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. Continuous-Flow System Produces Medical-Grade Water

    NASA Technical Reports Server (NTRS)

    Akse, James R.; Dahl, Roger W.; Wheeler, Richard R.

    2009-01-01

    A continuous-flow system utilizes microwave heating to sterilize water and to thermally inactivate endotoxins produced in the sterilization process. The system is designed for use in converting potable water to medical-grade water. Systems like this one could be used for efficient, small-scale production of medical- grade water in laboratories, clinics, and hospitals. This system could be adapted to use in selective sterilization of connections in ultra-pure-water-producing equipment and other equipment into which intrusion by microorganisms cannot be tolerated. Lightweight, port - able systems based on the design of this system could be rapidly deployed to remote locations (e.g., military field hospitals) or in response to emergencies in which the normal infrastructure for providing medical-grade water is disrupted. Larger systems based on the design of this system could be useful for industrial production of medical-grade water. The basic microwave-heating principle of this system is the same as that of a microwave oven: An item to be heated, made of a lossy dielectric material (in this case, flowing water) is irradiated with microwaves in a multimode microwave cavity. The heating is rapid and efficient because it results from absorption of microwave power throughout the volume of the lossy dielectric material. In this system, a copper tube having a length of 49.5 cm and a diameter of 2.25 cm serves as both the microwave cavity and the sterilization chamber. Microwave power is fed via a coaxial cable to an antenna mounted inside the tube at mid-length (see figure). Efficient power transfer occurs due to the shift in wavelength associated with the high permittivity of water combined with the strong coupling of 2.45-GHz microwaves with rotational-vibrational transitions of the dipolar water molecule.

  14. The impact of agricultural activities on water quality in oxbow lakes in the Mississippi Delta

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In the Mississippi Delta, agricultural activity is a major source of nonpoint source (NPS) pollutants. Sediment, nutrients and pesticides have been considered as priority NPS pollutants and greatly affect the water quality in this area. The impacts of agricultural activities on water quality in oxbo...

  15. 78 FR 71724 - Recordations, Water Carrier Tariffs, and Agricultural Contract Summaries

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-29

    ... Surface Transportation Board Recordations, Water Carrier Tariffs, and Agricultural Contract Summaries... 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...

  16. Water management in the Senegal River Delta: a continuing uncertainty

    NASA Astrophysics Data System (ADS)

    Mietton, M.; Dumas, D.; Hamerlynck, O.; Kane, A.; Coly, A.; Duvail, S.; Pesneaud, F.; Baba, M. L. O.

    2007-11-01

    Water management is the driving force behind the productivity of the ecosystems of the Senegal River Estuary and floodplains. It is dependent on human decision-making, but has been separated from the River's flooding since the building of the Diama Dam. The current objectives of the Office de Mise en Valeur du fleuve Sénégal (OMVS: Senegal River Development Agency) are mainly turned towards the development of irrigated agriculture on the former floodplains and since 2002 the production of hydroelectric power at Manantali. In October 2003, a four-metre-wide runoff canal, which quickly widened into a breach several hundred metres across, was dug in the Barbary Spit area to protect the city of Saint-Louis from heavy flooding. The hydraulic quality of the area downstream from the dam has improved to the extent that there is no longer any flooding there, but as the management of the dams concerns only the section of the river between Manantali and Diama, a certain amount of flood risk probably still persists. The intrusion of seawater into the estuary is also threatening ecosystems and fresh water supplies, and abruptly altering agricultural practices such as fruit and vegetable growing in the Gandiolais district. When added to the tentative efforts to coordinate the management of the two dams, with no management objective downstream from Diama, such permanent modifications impose serious constraints on the managers and residents of the lower delta. This paper presents an overview of the constraints and uncertainties at different levels and scales. This wholly human-wrought environment can be considered as a learning experience, where a large number of variables need to be monitored closely and an ongoing process of participatory analysis should be backed up by multidisciplinary research.

  17. Assessment of the soil water content temporal variations in an agricultural area of Galicia (NW Spain)

    NASA Astrophysics Data System (ADS)

    Mestas-Valero, Roger Manuel; Miras-Avalos, Jose Manuel; Paz-González, Antonio

    2010-05-01

    The direct and continuous assessment of the temporal variation on soil water content is of paramount importance for agricultural practices and, in particular, for the management of water resources. Soil water content is affected by many factors such as topography, particle size, clay and organic matter contents, and tillage systems. There are several techniques to measure or estimate soil water content. Among them, Frequency Domain Reflectometry (FDR) stands out. It is based on measuring the dielectrical constant of the soil environment. This technique allows to describe water dynamics in time and space, to determine the main patterns of soil moisture, the water uptake by roots, the evapotranspiration and the drainage. Therefore, the aim of this study was to assess the daily variation of soil water content in the root-influenced zone in plots devoted to maize and grassland as a function of the soil water volumetric content. The studied site is located in an experimental field of the Centre for Agricultural Research (CIAM) in Mabegondo located in the province of A Coruña, Spain (43°14'N, 8°15'W; 91 masl). The study was carried out from June 2008 to September 2009 in a field devoted to maize (Zea mays, L.) and another field devoted to grassland. The soil of these sites is silt-clay textured. Long-term mean annual temperature and rainfall figures are 13.3 °C and 1288 mm, respectively. During the study period, maize crop was subjected to conventional agricultural practices. A weekly evaluation of the phenological stage of the crop was performed. An EnviroSCAN FDR equipment, comprising six capacitance sensors, was installed in the studied sites following the manufacturer's recommendations, thus assuring a proper contact between the probe and the soil. Soil water content in the root-influenced zone (40 cm depth in grassland and 60 cm depth in maize were considered) was hourly monitored in 20 cm ranges (0-20 cm, 20-40 cm, and 40-60 cm) using FDR. Evaluations were

  18. Deficit irrigation and sustainable water-resource strategies in agriculture for China's food security.

    PubMed

    Du, Taisheng; Kang, Shaozhong; Zhang, Jianhua; Davies, William J

    2015-04-01

    More than 70% of fresh water is used in agriculture in many parts of the world, but competition for domestic and industrial water use is intense. For future global food security, water use in agriculture must become sustainable. Agricultural water-use efficiency and water productivity can be improved at different points from the stomatal to the regional scale. A promising approach is the use of deficit irrigation, which can both save water and induce plant physiological regulations such as stomatal opening and reproductive and vegetative growth. At the scales of the irrigation district, the catchment, and the region, there can be many other components to a sustainable water-resources strategy. There is much interest in whether crop water use can be regulated as a function of understanding of physiological responses. If this is the case, then agricultural water resources can be reallocated to the benefit of the broader community. We summarize the extent of use and impact of deficit irrigation within China. A sustainable strategy for allocation of agricultural water resources for food security is proposed. Our intention is to build an integrative system to control crop water use during different cropping stages and actively regulate the plant's growth, productivity, and development based on physiological responses. This is done with a view to improving the allocation of limited agricultural water resources.

  19. Deficit irrigation and sustainable water-resource strategies in agriculture for China’s food security

    PubMed Central

    Du, Taisheng; Kang, Shaozhong; Zhang, Jianhua; Davies, William J.

    2015-01-01

    More than 70% of fresh water is used in agriculture in many parts of the world, but competition for domestic and industrial water use is intense. For future global food security, water use in agriculture must become sustainable. Agricultural water-use efficiency and water productivity can be improved at different points from the stomatal to the regional scale. A promising approach is the use of deficit irrigation, which can both save water and induce plant physiological regulations such as stomatal opening and reproductive and vegetative growth. At the scales of the irrigation district, the catchment, and the region, there can be many other components to a sustainable water-resources strategy. There is much interest in whether crop water use can be regulated as a function of understanding of physiological responses. If this is the case, then agricultural water resources can be reallocated to the benefit of the broader community. We summarize the extent of use and impact of deficit irrigation within China. A sustainable strategy for allocation of agricultural water resources for food security is proposed. Our intention is to build an integrative system to control crop water use during different cropping stages and actively regulate the plant’s growth, productivity, and development based on physiological responses. This is done with a view to improving the allocation of limited agricultural water resources. PMID:25873664

  20. Land use effects on green water fluxes from agricultural production in Mato Grosso, Brazil

    NASA Astrophysics Data System (ADS)

    Lathuilliere, M. J.; Johnson, M. S.; Donner, S. D.

    2010-12-01

    The blue water/green water paradigm is increasingly used to differentiate between subsequent routing of precipitation once it reaches the soil. “Blue” water is that which infiltrates deep in the soil to become streams and aquifers, while “green” water is that which remains in the soil and is either evaporated (non-productive green water) or transpired by plants (productive green water). This differentiation in the fate of precipitation has provided a new way of thinking about water resources, especially in agriculture for which better use of productive green water may help to relieve stresses from irrigation (blue water). The state of Mato Grosso, Brazil, presents a unique case for the study of green water fluxes due to an expanding agricultural land base planted primarily to soybean, maize, sugar cane, and cotton. These products are highly dependent on green water resources in Mato Grosso where crops are almost entirely rain-fed. We estimate the change in green water fluxes from agricultural expansion for the 2000-2008 period in the state of Mato Grosso based on agricultural production data from the Instituto Brasileiro de Geografia e Estatísticas and a modified Penman-Monteith equation. Initial results for seven municipalities suggest an increase in agricultural green water fluxes, ranging from 1-10% per year, due primarily to increases in cropped areas. Further research is underway to elucidate the role of green water flux variations from land use practices on the regional water cycle.

  1. 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

  2. A Multiple-player-game Approach to Agricultural Water Use in Regions of Seasonal Drought

    NASA Astrophysics Data System (ADS)

    Lu, Z.

    2013-12-01

    In the wide distributed regions of seasonal drought, conflicts of water allocation between multiple stakeholders (which means water consumers and policy makers) are frequent and severe problems. These conflicts become extremely serious in the dry seasons, and are ultimately caused by an intensive disparity between the lack of natural resource and the great demand of social development. Meanwhile, these stakeholders are often both competitors and cooperators in water saving problems, because water is a type of public resource. Conflicts often occur due to lack of appropriate water allocation scheme. Among the many uses of water, the need of agricultural irrigation water is highly elastic, but this factor has not yet been made full use to free up water from agriculture use. The primary goal of this work is to design an optimal distribution scheme of water resource for dry seasons to maximize benefits from precious water resources, considering the high elasticity of agriculture water demand due to the dynamic of soil moisture affected by the uncertainty of precipitation and other factors like canopy interception. A dynamic programming model will be used to figure out an appropriate allocation of water resources among agricultural irrigation and other purposes like drinking water, industry, and hydropower, etc. In this dynamic programming model, we analytically quantify the dynamic of soil moisture in the agricultural fields by describing the interception with marked Poisson process and describing the rainfall depth with exponential distribution. Then, we figure out a water-saving irrigation scheme, which regulates the timetable and volumes of water in irrigation, in order to minimize irrigation water requirement under the premise of necessary crop yield (as a constraint condition). And then, in turn, we provide a scheme of water resource distribution/allocation among agriculture and other purposes, taking aim at maximizing benefits from precious water resources, or in

  3. Continuous water treatment by adsorption and electrochemical regeneration.

    PubMed

    Mohammed, F M; Roberts, E P L; Hill, A; Campen, A K; Brown, N W

    2011-05-01

    This study describes a process for water treatment by continuous adsorption and electrochemical regeneration using an air-lift reactor. The process is based on the adsorption of dissolved organic pollutants onto an adsorbent material (a graphite intercalation compound, Nyex(®)1000) and subsequent electrochemical regeneration of the adsorbent leading to oxidation of the adsorbed pollutant. Batch experiments were carried out to determine the adsorption kinetics and equilibrium isotherm for adsorption of a sample contaminant, the organic dye Acid Violet 17. The adsorbent circulation rate, the residence time distribution (RTD) of the reactor, and treatment by continuous adsorption and electrochemical regeneration were studied to investigate the process performance. The RTD behaviour could be approximated as a continuously stirred tank. It was found that greater than 98% removal could be achieved for continuous treatment by adsorption and electrochemical regeneration for feed concentrations of up to 300 mg L(-1). A steady state model has been developed for the process performance, assuming full regeneration of the adsorbent in the electrochemical cell. Experimental data and modelled predictions (using parameters for the adsorbent circulation rate, adsorption kinetics and isotherm obtained experimentally) of the dye removal achieved were found to be in good agreement.

  4. Modelling the water-agricultural sector in Rosetta, Egypt: exploring the interaction between water and food

    NASA Astrophysics Data System (ADS)

    Sušnik, Janez; Vamvakeridou-Lyroudia, Lydia; Savic, Dragan; Kapelan, Zoran

    2014-05-01

    An integrated System Dynamics Model for the Rosetta region, Egypt, assessing local water balance and agricultural yield to 2050, is presented. Fifty-seven simulations are analysed to better understand potential impacts on water and food security resulting from climate and social change and local/regional policy decisions related to the agricultural sector. Water limitation is a national issue: Egypt relies on the Nile for >95% of supply, and the flow of which is regulated by the Aswan High Dam. Egypt's share water of Aswan water is limited to 55 x 19 m3 yr-1. Any reduction in supply to the reservoir or increase in demand (e.g. from an expanding agricultural sector), has the potential to lead to a serious food and water supply situation. Results show current water resource over-exploitation. The remaining suite of 56 simulations, divided into seven scenarios, also mostly show resource overexploitation. Only under significant increases to Nile flow volumes was the trend reversed. Despite this, by threading together multiple local policies to reduce demand and improve/maintain supply, water resource exploitation can be mitigated while allowing for agricultural development. By changing cropping patterns, it is possible to improve yield and revenue, while using up to 21% less water in 2050 when compared with today. The results are useful in highlighting pathways to improving future water resource availability. Many policies should be considered in parallel, introducing redundancy into the policy framework. We do not suggest actual policy measures; this was beyond the scope of the work. This work highlights the utility of systems modelling of complex systems such as the water-food nexus, with the potential to extend the methodology to other studies and scales. In particular, the benefit of being able to easily modify and extend existing models in light of results from initial modelling efforts is cited. Analysis of initial results led to the hypothesis that by producing

  5. Investigation on Reservoir Operation of Agricultural Water Resources Management for Drought Mitigation

    NASA Astrophysics Data System (ADS)

    Cheng, C. L.

    2015-12-01

    Investigation on Reservoir Operation of Agricultural Water Resources Management for Drought Mitigation Chung-Lien Cheng, Wen-Ping Tsai, Fi-John Chang* Department of Bioenvironmental Systems Engineering, National Taiwan University, Da-An District, Taipei 10617, Taiwan, ROC.Corresponding author: Fi-John Chang (changfj@ntu.edu.tw) AbstractIn Taiwan, the population growth and economic development has led to considerable and increasing demands for natural water resources in the last decades. Under such condition, water shortage problems have frequently occurred in northern Taiwan in recent years such that water is usually transferred from irrigation sectors to public sectors during drought periods. Facing the uneven spatial and temporal distribution of water resources and the problems of increasing water shortages, it is a primary and critical issue to simultaneously satisfy multiple water uses through adequate reservoir operations for sustainable water resources management. Therefore, we intend to build an intelligent reservoir operation system for the assessment of agricultural water resources management strategy in response to food security during drought periods. This study first uses the grey system to forecast the agricultural water demand during February and April for assessing future agricultural water demands. In the second part, we build an intelligent water resources system by using the non-dominated sorting genetic algorithm-II (NSGA-II), an optimization tool, for searching the water allocation series based on different water demand scenarios created from the first part to optimize the water supply operation for different water sectors. The results can be a reference guide for adequate agricultural water resources management during drought periods. Keywords: Non-dominated sorting genetic algorithm-II (NSGA-II); Grey System; Optimization; Agricultural Water Resources Management.

  6. 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.

  7. Water spray ventilator system for continuous mining machines

    DOEpatents

    Page, Steven J.; Mal, Thomas

    1995-01-01

    The invention relates to a water spray ventilator system mounted on a continuous mining machine to streamline airflow and provide effective face ventilation of both respirable dust and methane in underground coal mines. This system has two side spray nozzles mounted one on each side of the mining machine and six spray nozzles disposed on a manifold mounted to the underside of the machine boom. The six spray nozzles are angularly and laterally oriented on the manifold so as to provide non-overlapping spray patterns along the length of the cutter drum.

  8. Remote sensing of optical properties in continuously stratified waters

    NASA Technical Reports Server (NTRS)

    Gordon, H. R.

    1978-01-01

    The radiative transfer equation is solved by Monte Carlo methods for natural waters in which the optical properties are distributed with depth. It is demonstrated that interpreting the reflectance of a continuously stratified ocean in terms of an equivalent homogeneous ocean yields the average of a particular combination of the water's optical properties over the dimensionless penetration depth. Although in general the dimensionless penetration depth cannot be remotely measured, a method is presented for estimating the actual penetration depth from the remote observations if the medium's absorption coefficient is known, independent of depth, and sufficiently large. The application of this to the remote measurement of the vertical distribution of suspended sediments is discussed in detail.

  9. Water isotopic ratios from a continuously melted ice core sample

    NASA Astrophysics Data System (ADS)

    Gkinis, V.; Popp, T. J.; Blunier, T.; Bigler, M.; Schüpbach, S.; Kettner, E.; Johnsen, S. J.

    2011-11-01

    A new technique for on-line high resolution isotopic analysis of liquid water, tailored for ice core studies is presented. We built an interface between a Wavelength Scanned Cavity Ring Down Spectrometer (WS-CRDS) purchased from Picarro Inc. and a Continuous Flow Analysis (CFA) system. The system offers the possibility to perform simultaneuous water isotopic analysis of δ18O and δD on a continuous stream of liquid water as generated from a continuously melted ice rod. Injection of sub μl amounts of liquid water is achieved by pumping sample through a fused silica capillary and instantaneously vaporizing it with 100% efficiency in a~home made oven at a temperature of 170 °C. A calibration procedure allows for proper reporting of the data on the VSMOW-SLAP scale. We apply the necessary corrections based on the assessed performance of the system regarding instrumental drifts and dependance on the water concentration in the optical cavity. The melt rates are monitored in order to assign a depth scale to the measured isotopic profiles. Application of spectral methods yields the combined uncertainty of the system at below 0.1‰ and 0.5‰ for δ18O and δD, respectively. This performance is comparable to that achieved with mass spectrometry. Dispersion of the sample in the transfer lines limits the temporal resolution of the technique. In this work we investigate and assess these dispersion effects. By using an optimal filtering method we show how the measured profiles can be corrected for the smoothing effects resulting from the sample dispersion. Considering the significant advantages the technique offers, i.e. simultaneuous measurement of δ18O and δD, potentially in combination with chemical components that are traditionally measured on CFA systems, notable reduction on analysis time and power consumption, we consider it as an alternative to traditional isotope ratio mass spectrometry with the possibility to be deployed for field ice core studies. We present

  10. Water, treated as the continuous liquid in and around cells.

    PubMed

    Van Oss, C J; Giese, R F; Docoslis, A

    2001-07-01

    In the quantitative treatment of non-covalent inter- and intra-cellular interactions taking place in water, in vitro as well as in vivo, it is essential to treat the surrounding and pervading liquid medium as the continuous medium. In the close vicinity of inter- and intra-cellular surfaces and of biopolymers the various different non-covalent forces may locally alter the structure of water in a number of ways, but these local structural changes can be quantitatively taken into account. The operative forces are: Lifshitz-van der Waals (LW) forces. Lewis acid-base (AB) forces and electrostatic (EL) forces. Of these, the AB forces are generally the preponderant ones, in aqueous media. This is due, inter alia, to the strong cohesive and adhesive hydrogen-bonding interactions typically occurring in and by water. Among the strong AB interactions occurring in water are hydrophobic attraction (the hydrophobic effect) and hydrophilic repulsion (hydration pressure). Also treated is the function of LW, AB and EL forces in: hydration; in the stability of particle and cell suspensions, the solubility of biopolymers, small organic solutes, and electrolytes; and in specific ligand-receptor (such as antigen-antibody) interactions.

  11. Carbon Sequestration Potential in Irrigated Agriculture: Greenhouse Gas Emissions and the Contribution of Water.

    NASA Astrophysics Data System (ADS)

    Rolston, D. E.; Hopmans, J. W.; van Kessel, C.; Six, J.; Paw U, K.; Plant, R.; Lee, J.; Kochendorfer, J.; Ideris, A. J.; MacIntyre, J.; Louie, D.; Matista, T.; Evatt, J.; Poch, R.; King, A. P.

    2006-12-01

    This study aimed to quantify CO2 and N2O release from an irrigated field in California's Sacramento Valley in an effort to determine greenhouse gas mitigation potentials through minimum tillage (MT) practices. Surface CO2 and N2O flux were monitored on the 30 ha, laser-leveled field site from September 2003 through August 2006. Additional field-representative flux data was collected from eddy-covariance masts and continuously sampling auto-chambers. Irrigation and run-off waters were collected and analyzed for total suspended solids (TSS), dissolved organic carbon (DOC), dissolved organic nitrogen (DON), nitrate-N, ammonium-N, total C and total N in the sediment. Overall, we found very little difference in CO2 flux, water composition, or sediment composition between the two tillage treatments. N2O flux was negligible in both systems until a fertilization and irrigation event occurred in each growing season, at which point the MT treatment showed slightly higher fluxes. NO3-N levels in the run-off exceeded drinking water quality standards only in irrigation events following fertilizer application. Collected CO2 and N2O data from this site will enable us to predict greenhouse gas emissions from similar agricultural systems in the California landscape. Our results indicate that the role of irrigation water in C budgets of agricultural systems is a significant factor in determining total C sequestration potential, but that short-term MT may not significantly decrease the contribution to global warming by irrigated agroecosystems and thus may not be a beneficial strategy for greenhouse gas mitigation.

  12. Evaluating the Impacts of an Agricultural Water Market in the Guadalupe River Basin, Texas: An Agent-based Modeling Approach

    NASA Astrophysics Data System (ADS)

    Du, E.; Cai, X.; Minsker, B. S.

    2014-12-01

    Agriculture comprises about 80 percent of the total water consumption in the US. Under conditions of water shortage and fully committed water rights, market-based water allocations could be promising instruments for agricultural water redistribution from marginally profitable areas to more profitable ones. Previous studies on water market have mainly focused on theoretical or statistical analysis. However, how water users' heterogeneous physical attributes and decision rules about water use and water right trading will affect water market efficiency has been less addressed. In this study, we developed an agent-based model to evaluate the benefits of an agricultural water market in the Guadalupe River Basin during drought events. Agricultural agents with different attributes (i.e., soil type for crops, annual water diversion permit and precipitation) are defined to simulate the dynamic feedback between water availability, irrigation demand and water trading activity. Diversified crop irrigation rules and water bidding rules are tested in terms of crop yield, agricultural profit, and water-use efficiency. The model was coupled with a real-time hydrologic model and run under different water scarcity scenarios. Preliminary results indicate that an agricultural water market is capable of increasing crop yield, agricultural profit, and water-use efficiency. This capability is more significant under moderate drought scenarios than in mild and severe drought scenarios. The water market mechanism also increases agricultural resilience to climate uncertainty by reducing crop yield variance in drought events. The challenges of implementing an agricultural water market under climate uncertainty are also discussed.

  13. Continuous Dependence on the Density for Stratified Steady Water Waves

    NASA Astrophysics Data System (ADS)

    Chen, Robin Ming; Walsh, Samuel

    2016-02-01

    There are two distinct regimes commonly used to model traveling waves in stratified water: continuous stratification, where the density is smooth throughout the fluid, and layer-wise continuous stratification, where the fluid consists of multiple immiscible strata. The former is the more physically accurate description, but the latter is frequently more amenable to analysis and computation. By the conservation of mass, the density is constant along the streamlines of the flow; the stratification can therefore be specified by prescribing the value of the density on each streamline. We call this the streamline density function. Our main result states that, for every smoothly stratified periodic traveling wave in a certain small-amplitude regime, there is an L ∞ neighborhood of its streamline density function such that, for any piecewise smooth streamline density function in that neighborhood, there is a corresponding traveling wave solution. Moreover, the mapping from streamline density function to wave is Lipschitz continuous in a certain function space framework. As this neighborhood includes piecewise smooth densities with arbitrarily many jump discontinues, this theorem provides a rigorous justification for the ubiquitous practice of approximating a smoothly stratified wave by a layered one. We also discuss some applications of this result to the study of the qualitative features of such waves.

  14. Water isotopic ratios from a continuously melted ice core sample

    NASA Astrophysics Data System (ADS)

    Gkinis, V.; Popp, T. J.; Blunier, T.; Bigler, M.; Schüpbach, S.; Johnsen, S. J.

    2011-06-01

    A new technique for on-line high resolution isotopic analysis of liquid water, tailored for ice core studies is presented. We build an interface between an Infra Red Cavity Ring Down Spectrometer (IR-CRDS) and a Continuous Flow Analysis (CFA) system. The system offers the possibility to perform simultaneuous water isotopic analysis of δ18O and δD on a continuous stream of liquid water as generated from a continuously melted ice rod. Injection of sub μl amounts of liquid water is achieved by pumping sample through a fused silica capillary and instantaneously vaporizing it with 100 % efficiency in a home made oven at a temperature of 170 °C. A calibration procedure allows for proper reporting of the data on the VSMOW scale. We apply the necessary corrections based on the assessed performance of the system regarding instrumental drifts and dependance on humidity levels. The melt rates are monitored in order to assign a depth scale to the measured isotopic profiles. Application of spectral methods yields the combined uncertainty of the system at below 0.1 ‰ and 0.5 ‰ for δ18O and δD, respectively. This performance is comparable to that achieved with mass spectrometry. Dispersion of the sample in the transfer lines limits the resolution of the technique. In this work we investigate and assess these dispersion effects. By using an optimal filtering method we show how the measured profiles can be corrected for the smoothing effects resulting from the sample dispersion. Considering the significant advantages the technique offers, i.e. simultaneuous measurement of δ18O and δD, potentially in combination with chemical components that are traditionally measured on CFA systems, notable reduction on analysis time and power consumption, we consider it as an alternative to traditional isotope ratio mass spectrometry with the possibility to be deployed for field ice core studies. We present data acquired in the framework of the NEEM deep ice core drilling project in

  15. Continuous-flow solar UVB disinfection reactor for drinking water.

    PubMed

    Mbonimpa, Eric Gentil; Vadheim, Bryan; Blatchley, Ernest R

    2012-05-01

    Access to safe, reliable sources of drinking water is a long-standing problem among people in developing countries. Sustainable solutions to these problems often involve point-of-use or community-scale water treatment systems that rely on locally-available resources and expertise. This philosophy was used in the development of a continuous-flow, solar UVB disinfection system. Numerical modeling of solar UVB spectral irradiance was used to define temporal variations in spectral irradiance at several geographically-distinct locations. The results of these simulations indicated that a solar UVB system would benefit from incorporation of a device to amplify ambient UVB fluence rate. A compound parabolic collector (CPC) was selected for this purpose. Design of the CPC was based on numerical simulations that accounted for the shape of the collector and reflectance. Based on these simulations, a prototype CPC was constructed using materials that would be available and inexpensive in many developing countries. A UVB-transparent pipe was positioned in the focal area of the CPC; water was pumped through the pipe to allow exposure of waterborne microbes to germicidal solar UVB radiation. The system was demonstrated to be effective for inactivation of Escherichia coli, and DNA-weighted UV dose was shown to govern reactor performance. The design of the reactor is expected to scale linearly, and improvements in process performance (relative to results from the prototype) can be expected by use of larger CPC geometry, inclusion of better reflective materials, and application in areas with greater ambient solar UV spectral irradiance than the location of the prototype tests. The system is expected to have application for water treatment among communities in (developing) countries in near-equatorial and tropical locations. It may also have application for disaster relief or military field operations, as well as in water treatment in areas of developed countries that receive

  16. Microbiological Implications of Periurban Agriculture and Water Reuse in Mexico City

    PubMed Central

    Mazari-Hiriart, Marisa; Ponce-de-León, Sergio; López-Vidal, Yolanda; Islas-Macías, Pilar; Amieva-Fernández, Rosa Isabel; Quiñones-Falconi, Francisco

    2008-01-01

    Background Recycled treated or untreated wastewater represents an important health challenge in developing countries due to potential water related microbiological exposure. Our aim was to assess water quality and health implications in a Mexico City periurban agricultural area. Methodology/Principal Findings A longitudinal study in the Xochimilco wetland area was conducted, and 42 sites were randomly selected from 211, including irrigation water canals and effluents of treatment plants. Sample collection took place during rainy and dry seasons (2000–2001). Microbiological parameters (total coliforms, fecal coliforms, streptococci/enterococci, and bacteria other than Vibrio grown on TCBS), Helicobacter pylori, and physicochemical parameters including trihalomethanes (THM) were determined. Fecal coliforms and fecal streptococci are appropriate indicators of human or animal fecal contamination. Fecal coliform counts surpass Mexican and World Health Organization irrigation water guidelines. Identified microorganisms associated with various pathologies in humans and domestic animals comprise Escherichia coli, Klebsiella spp., Salmonella spp., Enterobacter spp., Enterococcus spp., and Pseudomonas spp; H. pylori was also present in the water. An environmental characteristic of the canal system showed high Total Organic Carbon content and relatively low dissolved oxygen concentration; residual chlorine as a disinfection control is not efficient, but THMs do not represent a problem. During the rainy season, temperature and conductivity were higher; in contrast, pH, dissolved oxygen, ammonia, and residual chlorine were lower. This is related with the continuous load of feces from human and animal sources, and to the aquatic systems, which vary seasonally and exhibit evidence of lower water quality in effluents from treatment plants. Conclusions/Significance There is a need for improvement of wastewater treatment systems, as well as more efficient monitoring, regulation

  17. Continuous-flow water sampler for real-time isotopic water measurements

    NASA Astrophysics Data System (ADS)

    Carter, J.; Dennis, K.

    2013-12-01

    Measuring the stable isotopes of liquid water (δ18O and δD) is a tool familiar to many Earth scientists, but most current techniques require discrete sampling. For example, isotope ratio mass spectrometry requires the collection of aliquots of water that are then converted to CO2, CO or H2 for analysis. Similarly, laser-based techniques, such as Cavity Ring-Down Spectroscopy (CRDS) convert discrete samples (typically < 2μL) of liquid water to water vapor using a flash vaporization process. By requiring the use of discrete samples fine-scale spatial and temporal studies of changes in δ18O and δD are limited. Here we present a continuous-flow water sampler that will enable scientists to probe isotopic changes in real-time, with applications including, but not limited to, quantification of the 'amount effect' (Dansgaard, 1964) during an individual precipitation event or storm track, real-time mixing of water in river systems, and shipboard continuous water measurements (Munksgaard et al., 2012). Due to the inherent ability of CRDS to measure a continuous flow of water vapor it is an ideal candidate for interfacing with a continuous water sampling system. Here we present results from the first commercially available continuous-flow water sampler, developed by engineers at Picarro. This peripheral device is compatible with Picarro CRDS isotopic water analyzers, allowing real-time, continuous isotopic measurements of liquid water. The new device, which expands upon the design of Munskgaard et al. (2011), utilizes expanded polytetrafluoroethylene (ePTFE) membrane technology to continuously generate gas-phase water, while liquid water is pumped through the system. The water vapor subsequently travels to the CRDS analyzer where the isotopic ratios are measured and recorded. The generation of water vapor using membrane technology is sensitive to environmental conditions, which if not actively control, lead to sustainable experimental noise and drift. Consequently, our

  18. The many faces and facets of water in agriculture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The many forms of water (i.e., water vapor, fog, rain, snow, hail and ice) are essential, but can be detrimental, for maintaining an adequate food supply and a productive and healthy environment for all forms of life. Greater limitations on water availability and quality call for research on water c...

  19. Agricultural water requirements for commercial production of cranberries

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Abundant water resources are essential for the commercial production of cranberries, which use irrigated water for frost protection, soil moisture management, and harvest and winter floods. Given water resource demands in southeastern Massachusetts, we sought to quantify the annual water requirement...

  20. Model Hosting for continuous updating and transparent Water Resources Management

    NASA Astrophysics Data System (ADS)

    Jódar, Jorge; Almolda, Xavier; Batlle, Francisco; Carrera, Jesús

    2013-04-01

    Numerical models have become a standard tool for water resources management. They are required for water volume bookkeeping and help in decision making. Nevertheless, numerical models are complex and they can be used only by highly qualified technicians, which are often far from the decision makers. Moreover, they need to be maintained. That is, they require updating of their state, by assimilation of measurements, natural and anthropic actions (e.g., pumping and weather data), and model parameters. Worst, their very complexity implies that are they viewed as obscure and far, which hinders transparency and governance. We propose internet model hosting as an alternative to overcome these limitations. The basic idea is to keep the model hosted in the cloud. The model is updated as new data (measurements and external forcing) becomes available, which ensures continuous maintenance, with a minimal human cost (only required to address modelling problems). Internet access facilitates model use not only by modellers, but also by people responsible for data gathering and by water managers. As a result, the model becomes an institutional tool shared by water agencies to help them not only in decision making for sustainable management of water resources, but also in generating a common discussion platform. By promoting intra-agency sharing, the model becomes the common official position of the agency, which facilitates commitment in their adopted decisions regarding water management. Moreover, by facilitating access to stakeholders and the general public, the state of the aquifer and the impacts of alternative decisions become transparent. We have developed a tool (GAC, Global Aquifer Control) to address the above requirements. The application has been developed using Cloud Computing technologies, which facilitates the above operations. That is, GAC automatically updates the numerical models with the new available measurements, and then simulates numerous management options

  1. Ground-water quality beneath irrigated agriculture in the central High Plains aquifer, 1999-2000

    USGS Publications Warehouse

    Bruce, Breton W.; Becker, Mark F.; Pope, Larry M.; Gurdak, Jason J.

    2003-01-01

    In 1999 and 2000, 30 water-quality monitoring wells were installed in the central High Plains aquifer to evaluate the quality of recently recharged ground water in areas of irrigated agriculture and to identify the factors affecting ground-water quality. Wells were installed adjacent to irrigated agricultural fields with 10- or 20-foot screened intervals placed near the water table. Each well was sampled once for about 100 waterquality constituents associated with agricultural practices. Water samples from 70 percent of the wells (21 of 30 sites) contained nitrate concentrations larger than expected background concentrations (about 3 mg/L as N) and detectable pesticides. Atrazine or its metabolite, deethylatrazine, were detected with greater frequency than other pesticides and were present in all 21 samples where pesticides were detected. The 21 samples with detectable pesticides also contained tritium concentrations large enough to indicate that at least some part of the water sample had been recharged within about the last 50 years. These 21 ground-water samples are considered to show water-quality effects related to irrigated agriculture. The remaining 9 groundwater samples contained no pesticides, small tritium concentrations, and nitrate concentrations less than 3.45 milligrams per liter as nitrogen. These samples are considered unaffected by the irrigated agricultural land-use setting. Nitrogen isotope ratios indicate that commercial fertilizer was the dominant source of nitrate in 13 of the 21 samples affected by irrigated agriculture. Nitrogen isotope ratios for 4 of these 21 samples were indicative of an animal waste source. Dissolved-solids concentrations were larger in samples affected by irrigated agriculture, with large sulfate concentrations having strong correlation with large dissolved solids concentrations in these samples. A strong statistical correlation is shown between samples affected by irrigated agriculture and sites with large rates of

  2. Agricultural production and water use scenarios in Cyprus under global change

    NASA Astrophysics Data System (ADS)

    Bruggeman, Adriana; Zoumides, Christos; Camera, Corrado; Pashiardis, Stelios; Zomeni, Zomenia

    2014-05-01

    In many countries of the world, food demand exceeds the total agricultural production. In semi-arid countries, agricultural water demand often also exceeds the sustainable supply of water resources. These water-stressed countries are expected to become even drier, as a result of global climate change. This will have a significant impact on the future of the agricultural sector and on food security. The aim of the AGWATER project consortium is to provide recommendations for climate change adaptation for the agricultural sector in Cyprus and the wider Mediterranean region. Gridded climate data sets, with 1-km horizontal resolution were prepared for Cyprus for 1980-2010. Regional Climate Model results were statistically downscaled, with the help of spatial weather generators. A new soil map was prepared using a predictive modelling and mapping technique and a large spatial database with soil and environmental parameters. Stakeholder meetings with agriculture and water stakeholders were held to develop future water prices, based on energy scenarios and to identify climate resilient production systems. Green houses, including also hydroponic systems, grapes, potatoes, cactus pears and carob trees were the more frequently identified production systems. The green-blue-water model, based on the FAO-56 dual crop coefficient approach, has been set up to compute agricultural water demand and yields for all crop fields in Cyprus under selected future scenarios. A set of agricultural production and water use performance indicators are computed by the model, including green and blue water use, crop yield, crop water productivity, net value of crop production and economic water productivity. This work is part of the AGWATER project - AEIFORIA/GEOGRO/0311(BIE)/06 - co-financed by the European Regional Development Fund and the Republic of Cyprus through the Research Promotion Foundation.

  3. 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...

  4. Simulations of Limited-Water Irrigation Management Options for Corn in Dryland Agriculture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Diminishing land and water resources due to increasing demands from rapid population growth calls for increasing water use efficiency of irrigated crops. To produce more for every drop of water used in agriculture, it is important to develop location specific alternate agronomic practices vis-à-vis...

  5. Voluntary arrangements to cope with diffuse pollution from agriculture and their role in European water policy.

    PubMed

    Heinz, I; Andrews, K; Brouwer, F; Zabel, T

    2002-01-01

    A limited number of Member States in the EU have gained experience with establishing co-operative agreements between agriculture and the water sector. Their main aim is to reduce or prevent water pollution caused by intensive farming practices. The research has shown that significant changes in farming practices have been achieved as a result of negotiation between farmers and water suppliers. Consequently, in many catchment areas improvements in water quality can be observed. Co-operative agreements have the important advantage that the measures taken can be tailored to the different local conditions in catchment areas. Reducing diffuse pollution resulting from intensive agriculture is one of the main issues of the EU Water Framework Directive. The current paper builds on the results of a EU-wide research project which examines the role co-operative agreements can play in water policy and the Common Agricultural Policy.

  6. Complex water management in modern agriculture: Trends in the water-energy-food nexus over the High Plains Aquifer.

    PubMed

    Smidt, Samuel J; Haacker, Erin M K; Kendall, Anthony D; Deines, Jillian M; Pei, Lisi; Cotterman, Kayla A; Li, Haoyang; Liu, Xiao; Basso, Bruno; Hyndman, David W

    2016-10-01

    In modern agriculture, the interplay between complex physical, agricultural, and socioeconomic water use drivers must be fully understood to successfully manage water supplies on extended timescales. This is particularly evident across large portions of the High Plains Aquifer where groundwater levels have declined at unsustainable rates despite improvements in both the efficiency of water use and water productivity in agricultural practices. Improved technology and land use practices have not mitigated groundwater level declines, thus water management strategies must adapt accordingly or risk further resource loss. In this study, we analyze the water-energy-food nexus over the High Plains Aquifer as a framework to isolate the major drivers that have shaped the history, and will direct the future, of water use in modern agriculture. Based on this analysis, we conclude that future water management strategies can benefit from: (1) prioritizing farmer profit to encourage decision-making that aligns with strategic objectives, (2) management of water as both an input into the water-energy-food nexus and a key incentive for farmers, (3) adaptive frameworks that allow for short-term objectives within long-term goals, (4) innovative strategies that fit within restrictive political frameworks, (5) reduced production risks to aid farmer decision-making, and (6) increasing the political desire to conserve valuable water resources. This research sets the foundation to address water management as a function of complex decision-making trends linked to the water-energy-food nexus. Water management strategy recommendations are made based on the objective of balancing farmer profit and conserving water resources to ensure future agricultural production. PMID:27344509

  7. 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

  8. Continued Water-Based Phase Change Material Heat Exchanger Development

    NASA Technical Reports Server (NTRS)

    Hansen, Scott W.; Sheth, Rubik B.; Poynot, Joe; Giglio, Tony; Ungar, Gene K.

    2015-01-01

    In a cyclical heat load environment such as low Lunar orbit, a spacecraft's radiators are not sized to meet the full heat rejection demands. Traditionally, a supplemental heat rejection device (SHReD) such as an evaporator or sublimator is used to act as a "topper" to meet the additional heat rejection demands. Utilizing a Phase Change Material (PCM) heat exchanger (HX) as a SHReD provides an attractive alternative to evaporators and sublimators as PCM HX's do not use a consumable, thereby leading to reduced launch mass and volume requirements. In continued pursuit of water PCM HX development two full-scale, Orion sized water-based PCM HX's were constructed by Mezzo Technologies. These HX's were designed by applying prior research on freeze front propagation to a full-scale design. Design options considered included bladder restraint and clamping mechanisms, bladder manufacturing, tube patterns, fill/drain methods, manifold dimensions, weight optimization, and midplate designs. Two units, Units A and B, were constructed and differed only in their midplate design. Both units failed multiple times during testing. This report highlights learning outcomes from these tests and are applied to a final sub-scale PCM HX which is slated to be tested on the ISS in early 2017.

  9. Continued Water-Based Phase Change Material Heat Exchanger Development

    NASA Technical Reports Server (NTRS)

    Hansen, Scott; Poynot, Joe

    2014-01-01

    In a cyclical heat load environment such as low Lunar orbit, a spacecraft's radiators are not sized to reject the full heat load requirement. Traditionally, a supplemental heat rejection device (SHReD) such as an evaporator or sublimator is used to act as a "topper" to meet the additional heat rejection demands. Utilizing a Phase Change Material (PCM) heat exchanger (HX) as a SHReD provides an attractive alternative to evaporators and sublimators as PCM HXs do not use a consumable, thereby leading to reduced launch mass and volume requirements. In continued pursuit of water PCM HX development two full-scale, Orion sized water-based PCM HX's were constructed by Mezzo Technologies. These HX's were designed by applying prior research and experimentation to the full scale design. Design options considered included bladder restraint and clamping mechanisms, bladder manufacturing, tube patterns, fill/drain methods, manifold dimensions, weight optimization, and midplate designs. Design and construction of these HX's led to successful testing of both PCM HX's.

  10. 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

  11. Continuous on-line water vapor isotope measurements in Antarctica

    NASA Astrophysics Data System (ADS)

    Landsberg, Janek; Romanini, Daniele; Holmen, Kim; Isaksson, Elisabeth; Meijer, Harro; Kerstel, Erik

    2010-05-01

    In the context of a globally warming climate it is crucial to study the climate variability in the past and to understand the underlying mechanisms (1). Precipitation deposited on the polar ice caps provides a means to retrieve information on temperature changes (through the paleo-temperature dependence of the isotopic composition of the ice) and atmospheric composition (of gas stored in bubbles in the ice) on time scales from one to almost one million years, with sub-annual resolution in the most recent centuries. However, it is now widely recognized that the calibration of the paleo-thermometer is highly problematic. For this reason attempts to model the global water cycle, including the isotope signals, are ongoing with the aim of providing a more physical basis of the isotope - temperature relation. Currently, there is a large divergence in the results obtained by different modeling strategies. The missing link in these model studies is their forcing by experimental data on the pre-deposition isotopic composition of the vapor phase compartment of the hydrological cycle. We propose to measure the isotopic composition of moisture carried towards and deposited on Antarctica, in order to constrain the numerical models. In this context we are developing a modified, more sensitive and precise, version of a laser water vapor isotope spectrometer, originally designed for stratospheric studies (2, 3). This instrument, which will first be operated at the Norwegian station of Troll in Queen Maud Land, will enable the continuous, online measurement of all three stable isotope ratios of atmospheric water vapor. So far, such data is non-existent. Our data should improve the validity of the models and improve the understanding of the physical mechanisms at the basis of the isotope thermometer. This in turn will lead to an increased confidence in the predictions of (general circulation) models concerning climate variability. (1) International Panel on Climate Change (IPCC), 4

  12. The Management Options of Water for the Development of Agriculture in Dry Areas

    NASA Astrophysics Data System (ADS)

    Irshad, M.; Inoue, M.; Ashraf, M.; Al-Busaidi, A.

    The natural resource base of land, water and vegetation in arid and semi arid areas is highly fragile and greatly vulnerable to degradation especially in the developing countries. The demand for water is constantly increasing as a result of population growth and the expansion of agriculture and industry. Fresh water resources are limited in the arid and semi-arid areas whereas the existing water resources are often overused and misused. The lack of water management in the arid areas generated numerous economic, social and ecological issues. Agriculture currently accounts for nearly 70-80% of water consumption in the developing countries. The productivity of water use in agriculture needs to enhance in order both to avoid exacerbating the water crisis and to prevent considerable food shortages. More efficient use of existing water resources and adequate management of soils could prove to be the effective tool for improving arid lands. The technologies, skills and capital resources required to overcome the poor and extreme distribution of water resources through storage and transfer are not available and widely used. As a consequence there is critically low access to water for agriculture, drinking and sanitation and the environment. Poor access to water is among the leading factors hindering sustainable development in semi-arid and arid regions. Conventional irrigation management should be revised to ensure maximum water productivity instead of land productivity for dry farming systems. Under conditions of increasing water scarcity, the key to sustaining rural livelihoods is improving the productivity and reliability of rainfed agriculture by using limited rainfall more productively, through optimal on-farm soil, water and crop management practices that conserve soil moisture and increase water use efficiency. Conserving and augmenting water supplies through rainwater harvesting and precision irrigation provide new opportunity for productive dry land farming

  13. A continuous active monitoring approach to identify cross-connections between potable water and effluent distribution systems.

    PubMed

    Friedler, E; Alfiya, Y; Shaviv, A; Gilboa, Y; Harussi, Y; Raize, O

    2015-03-01

    A continuous active monitoring approach was developed for identification of cross-connections between potable water supply systems and treated wastewater effluent reuse distribution systems. The approach is based on monitoring the oxidation reduction potential (ORP) at the potable water system while injecting sulfite (a reducing agent) into the effluent line. A sharp decrease in the ORP of the potable water would indicate a cross-connection event. The approach was tested in batch experiments on treated municipal wastewater effluent of varying degree of treatment, and at dilution ratios of up to 1:100 (effluent/potable). The approach was then examined under continuous flow conditions, which simulated cross-connection events at various dilution ratios (up to 1:100). In the continuous runs, differences between the potable water ORP and the effluent-potable water mixture (containing sulfite as sodium bisulfite (SBS)) ORP were 450-630 mV. This suggests high potential for identifying a cross-connection event. Implementation of the approach includes adding sulfite to effluent used for agricultural irrigation; hence, possible effects on soil and on crops were studied in soil columns and pots planted with basil (Ocimum basilicum) as a model plant. No negative effects of sulfite addition to the irrigation effluent were observed in the irrigated soils and plants, and therefore, it could be safely implemented also in agricultural applications. PMID:25701471

  14. A continuous active monitoring approach to identify cross-connections between potable water and effluent distribution systems.

    PubMed

    Friedler, E; Alfiya, Y; Shaviv, A; Gilboa, Y; Harussi, Y; Raize, O

    2015-03-01

    A continuous active monitoring approach was developed for identification of cross-connections between potable water supply systems and treated wastewater effluent reuse distribution systems. The approach is based on monitoring the oxidation reduction potential (ORP) at the potable water system while injecting sulfite (a reducing agent) into the effluent line. A sharp decrease in the ORP of the potable water would indicate a cross-connection event. The approach was tested in batch experiments on treated municipal wastewater effluent of varying degree of treatment, and at dilution ratios of up to 1:100 (effluent/potable). The approach was then examined under continuous flow conditions, which simulated cross-connection events at various dilution ratios (up to 1:100). In the continuous runs, differences between the potable water ORP and the effluent-potable water mixture (containing sulfite as sodium bisulfite (SBS)) ORP were 450-630 mV. This suggests high potential for identifying a cross-connection event. Implementation of the approach includes adding sulfite to effluent used for agricultural irrigation; hence, possible effects on soil and on crops were studied in soil columns and pots planted with basil (Ocimum basilicum) as a model plant. No negative effects of sulfite addition to the irrigation effluent were observed in the irrigated soils and plants, and therefore, it could be safely implemented also in agricultural applications.

  15. 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.

  16. 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

  17. Virtual water flows in the international trade of agricultural products of China.

    PubMed

    Zhang, Yu; Zhang, Jinhe; Tang, Guorong; Chen, Min; Wang, Lachun

    2016-07-01

    With the rapid development of the economy and population, water scarcity and poor water quality caused by water pollution have become increasingly severe in China. Virtual water trade is a useful tool to alleviate water shortage. This paper focuses on a comprehensive study of China's international virtual water flows from agricultural products trade and completes a diachronic analysis from 2001 to 2013. The results show that China was in trade surplus in relation to the virtual water trade of agricultural products. The exported virtual water amounted to 29.94billionm(3)/yr. while 155.55billionm(3)/yr. was embedded in imported products. The trend that China exported virtual water per year was on the decline while the imported was on a rising trend. Virtual water trade of China was highly concentrated. Not all of the exported products had comparative advantages in virtual water content. Imported products were excessively concentrated on water intensive agricultural products such as soya beans, cotton, and palm oil. The exported virtual water mainly flowed to the Republic of Korea, Hong Kong of China and Japan, while the imported mainly flowed from the United States of America, Brazil and Argentina. From the ethical point of view, the trade partners were classified into four types in terms of "net import" and "water abundance": mutual benefit countries, such as Australia and Canada; unilateral benefit countries, such as Mongolia and Norway; supported countries, such as Egypt and Singapore; and double pressure countries, such as India and Pakistan. Virtual water strategy refers to water resources, agricultural products and human beings. The findings are beneficial for innovating water resources management system, adjusting trade structure, ensuring food security in China, and promoting the construction of national ecological security system.

  18. Virtual water flows in the international trade of agricultural products of China.

    PubMed

    Zhang, Yu; Zhang, Jinhe; Tang, Guorong; Chen, Min; Wang, Lachun

    2016-07-01

    With the rapid development of the economy and population, water scarcity and poor water quality caused by water pollution have become increasingly severe in China. Virtual water trade is a useful tool to alleviate water shortage. This paper focuses on a comprehensive study of China's international virtual water flows from agricultural products trade and completes a diachronic analysis from 2001 to 2013. The results show that China was in trade surplus in relation to the virtual water trade of agricultural products. The exported virtual water amounted to 29.94billionm(3)/yr. while 155.55billionm(3)/yr. was embedded in imported products. The trend that China exported virtual water per year was on the decline while the imported was on a rising trend. Virtual water trade of China was highly concentrated. Not all of the exported products had comparative advantages in virtual water content. Imported products were excessively concentrated on water intensive agricultural products such as soya beans, cotton, and palm oil. The exported virtual water mainly flowed to the Republic of Korea, Hong Kong of China and Japan, while the imported mainly flowed from the United States of America, Brazil and Argentina. From the ethical point of view, the trade partners were classified into four types in terms of "net import" and "water abundance": mutual benefit countries, such as Australia and Canada; unilateral benefit countries, such as Mongolia and Norway; supported countries, such as Egypt and Singapore; and double pressure countries, such as India and Pakistan. Virtual water strategy refers to water resources, agricultural products and human beings. The findings are beneficial for innovating water resources management system, adjusting trade structure, ensuring food security in China, and promoting the construction of national ecological security system. PMID:26994788

  19. Summary of reported agriculture and irrigation water use in Jefferson County, Arkansas, 1991

    USGS Publications Warehouse

    Holland, T.W.; Manning, C.A.; Stafford, K.L.

    1993-01-01

    This report summarizes the 1991 water-use reporting through the Conservation District Office in Jefferson County, Arkansas. The number of withdrawal registrations for Jefferson County was 1,636 (1,227 groundwater and 409 surface water). Water with- drawals reported during the registration process total 5.64 Mgal/day (3.89 Mgal/d groundwater and 1.75 Mgal/d surface water) for agriculture and 197.49 Mgal/d (161.39 Mgal/d groundwater and 36.10 Mgal/d surface water) for irrigation. The regis- tration reports for 1991 indicate that this water was applied to 132,667 acres of land to irrigate rice, sorghum, corn, soybeans, milo, cash grains, cotton, vegetables, and unknown crops as well as for the agricultural uses of animal aquaculture, crawfish, minnows, timber, and ducks. (USGS) {descriptors: *Water use, *Arkansas, *Jefferson County, Selective withdrawal, Groundwater, Surface water

  20. Summary of reported agriculture and irrigation water use in Monroe County, Arkansas, 1991

    USGS Publications Warehouse

    Holland, T.W.; Manning, C.A.; Stafford, K.L.

    1993-01-01

    This report summarizes the 1991 water-use reporting through the Conservation District Office in Monroe County, Arkansas. The number of withdrawal registrations for Monroe County was 1,886 (1,677 groundwater and 209 surface water). Water withdrawals reported during the registration process total 8.87 Mgal/d (5.75 Mgal/d groundwater and 3.12 Mgal/d surface water) for agriculture and 210.61 Mgal/d (190.99 Mgal/d groundwater and 19.62 Mgal/d surface water) for irrigation. The registration reports for 1991 indicate that this water was applied to 127,670 acres of land to irrigate rice, sorghum, soybeans, milo, cash grains, cotton, hay, and unknown crops, as well as for agricultural uses of animal aquaculture, minnows, and ducks. {descriptors: *Water use, *Arkansas, *Monroe County, Selective withdrawal, Groundwater, Surface water

  1. Issues of sustainable irrigated agriculture in the San Joaquin Valley of California in a changing regulatory environment concerning water quality and protection of wildlife

    SciTech Connect

    Quinn, N.W.T.; Delamore, M.L.

    1994-06-01

    Since the discovery of selenium toxicosis in the Kesterson Reservoir in the San Joaquin Valley, California, public perception of irrigated agriculture as a benign competitor for California`s developed water supply has been changed irrevocably. Subsurface return flows from irrigated agriculture were implicated as the source of selenium which led to incidents of reproductive failure in waterfowl and threatened survival of other fish and wildlife species. Stringent water quality objectives were promulgated to protect rivers, tributaries, sloughs and other water bodies receiving agricultural discharges from selenium contamination. Achieving these objectives was left to the agricultural water districts, federal and state agencies responsible for drainage and water quality enforcement in the San Joaquin Basin. This paper describes some of the strategies to improve management of water resources and water quality in response to these new environmental objectives. Similar environmental objectives will likely be adopted by other developed and developing countries with large regions of arid zone agriculture and susceptible wildlife resources. A series of simulation models have been developed over the past four years to evaluate regional drainage management strategies such as: irrigation source control; drainage recycling; selective retirement of agricultural land; regional shallow ground water pumping; coordination of agricultural drainage, wetland and reservoir releases; and short-term ponding of drainage water. A new generation of Geographic Information Service-based software is under development to bridge the gap between planning and program implementation. Use of the decision support system will allow water districts and regulators to continuously monitor drainage discharges to the San Joaquin River in real-time and to assess impacts of management strategies that have been implemented to take advantage of the River`s assimilative capacity for trace elements and salts.

  2. Agricultural water and energy use in the Senegal River Valley

    NASA Astrophysics Data System (ADS)

    Masiyandima, M. C.; Sow, A.

    2015-12-01

    Assessment of the productivity of irrigation water is important measuring the performance of irrigation schemes especially in water scarce areas. Equally important for performance is the energy cost of providing water for irrigation. Sahel irrigation schemes are dependent on pumping water from rivers into a network of gravity operated channels. In the Senegal River valley in Senegal the cost of pumping water and for irrigation has been estimated to be 20-25% of total rice production costs. Irrigation schemes in the valley are characterized by low water productivity. We analysed rice production, irrigation water use and energy use for supplying irrigation water at Pont Gendarme, Ndiawar and Ngallenka MCA irrigation schemes in the Senegal River valley. For the 2013 rainfall season the mean yield ranged between 6 and 8t ha-1. Dry season yield ranged between 1.7 and 6.8t ha-1. Energy use for irrigation in the Ndiawar irrigation scheme was 8kg MJ-1 and 6.4kg MJ-1 in the 2013 and 2014 rainfall seasons respectively. In 2014 (rainfall season) energy productivity of irrigation water was 8.5, 8.0 and 16.4 kg MJ-1 at Ngallenka MCA, Ndiawar and Pont Gendarme respectively. Dry season (2014) energy productivity at Ndiawar and Pont Gendarme was 3.4 and 11.2kg MJ-1 respectively. Productivity of irrigation water was similar for all schemes (0.37kg m-3 at Pont Gendarme, 0.42kg m-3 at Ngallenka MCA, and 0.41kg m-3 Ndiawar). Energy use for the supply of irrigation water in the rainfall season ranged from 403 to 1,002MJ ha-1. Dry season irrigation energy use was 589MJ ha-1 Pont Gendarme and 331MJ ha-1 at Ndiawar. Reducing water use in these schemes through better water management will result in lower production costs and increased margins for the farmers. The observations from 2013 - 2014 highlight the importance of using both water and energy productivity to assess performance of irrigation schemes.

  3. Co-Adapting Water Demand and Supply to Changing Climate in Agricultural Water Systems, A Case Study in Northern Italy

    NASA Astrophysics Data System (ADS)

    Giuliani, M.; Li, Y.; Mainardi, M.; Arias Munoz, C.; Castelletti, A.; Gandolfi, C.

    2013-12-01

    Exponentially growing water demands and increasing uncertainties in the hydrologic cycle due to changes in climate and land use will challenge water resources planning and management in the next decade. Improving agricultural productivity is particularly critical, being this sector the one characterized by the highest water demand. Moreover, to meet projected growth in human population and per-capita food demand, agricultural production will have to significantly increase in the next decades, even though water availability is expected to decrease due to climate change impacts. Agricultural systems are called to adapt their strategies (e.g., changing crop patterns and the corresponding water demand, or maximizing the efficiency in the water supply modifying irrigation scheduling and adopting high efficiency irrigation techniques) in order to re-optimize the use of limited water resources. Although many studies have assessed climate change impacts on agricultural practices and water management, most of them assume few scenarios of water demand or water supply separately, while an analysis of their reciprocal feedbacks is still missing. Moreover, current practices are generally established according to historical agreements and normative constraints and, in the absence of dramatic failures, the shift toward more efficient water management is not easily achievable. In this work, we propose to activate an information loop between farmers and water managers to improve the effectiveness of agricultural water management practices by matching the needs of the farmers with the design of water supply strategies. The proposed approach is tested on a real-world case study, namely the Lake Como serving the Muzza-Bassa Lodigiana irrigation district (Italy). A distributed-parameter, dynamic model of the system allows to simulate crop growth and the final yield over a range of hydro-climatic conditions, irrigation strategies and water-related stresses. The spatial component of the

  4. Measuring pesticides in surface waters - continuous versus event-based sampling design

    NASA Astrophysics Data System (ADS)

    Eyring, J.; Bach, M.; Frede, H.-G.

    2009-04-01

    Monitoring pesticides in surface waters is still a work- and cost-intensive procedure. Therefore, studies are normally carried out with a low monitoring frequency or with only a small selection of substances to be analyzed. In this case, it is not possible to picture the high temporal variability of pesticide concentrations, depending on application dates, weather conditions, cropping seasons and other factors. In 2007 the Institute of Landscape Ecology and Resource Management at Giessen University implemented a monitoring program during two pesticide application periods aiming to produce a detailed dataset of pesticide concentration for a wide range of substances, and which would also be suitable for the evaluation of catchment-scale pesticide exposure models. The Weida catchment in Thuringia (Eastern Germany) was selected as study area due to the availability of detailed pesticide application data for this region. The samples were taken from the river Weida at the gauge Zeulenroda, where it flows into a drinking water reservoir. The catchment area is 102 km². 67% of the area are in agricultural use, the main crops being winter wheat, maize, winter barley and winter rape. Dominant soil texture classes are loamy sand and loamy silt. About one third of the agricultural area is drained. The sampling was carried out in cooperation with the water supply agency of Thuringia (Fernwasserversorgung Thueringen). The sample analysis was done by the Institute of Environmental Research at Dortmund University. Two sampling schemes were carried out using two automatic samplers: continuous sampling with composite samples bottled two times per week and event-based sampling triggered by a discharge threshold. 53 samples from continuous sampling were collected. 19 discharge events were sampled with 45 individual samples (one to six per event). 34 pesticides and two metabolites were analyzed. 21 compounds were detected, nine of which having concentrations above the drinking water

  5. Design and implementation of a continuous microwave heating system for ballast water treatment.

    PubMed

    Boldor, Dorin; Balasubramanian, Sundar; Purohit, Shreya; Rusch, Kelly A

    2008-06-01

    A continuous microwave system to treat ballast water inoculated with different invasive species was designed and installed atthe Louisiana State University Agricultural Center. The effectiveness of the system to deliver the required heating loads to inactivate the organisms present was studied. The targeted organisms were microalgae (Nannochloropsis oculata), zooplankton at two different growth stages (newly hatched brine shrimp-Artemia nauplii and adult Artemia), and oyster larvae (Crassosstrea virginica). The system was tested at two different flow rates (1 and 2 liters per min) and power levels (2.5 and 4.5 kW). Temperature profiles indicate that, depending on the species present and the growth stage, the maximum temperature increase will vary from 11.8 to 64.9 degrees C. The continuous microwave heating system delivered uniform and near-instantaneous heating at the outlet proving its effectiveness. The power absorbed and power efficiency varied for the species present. More than 80% power utilization efficiency was obtained at all flow rate and microwave power combinations for microalgae, Artemia nauplii and adults. Test results indicated that microwave treatment can be an effective tool for ballast water treatment, and current high treatment costs notwithstanding, this technique can be added as supplemental technology to the palette of existing treatment methods. PMID:18589975

  6. 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

  7. Relations of Water Quality to Agricultural Chemical Use and Environmental Setting at Various Scales - Results from Selected Studies of the National Water-Quality Assessment Program

    USGS Publications Warehouse

    ,

    2008-01-01

    In 1991, the U.S. Geological Survey (USGS) began studies of 51 major river basins and aquifers across the United States as part of the National Water-Quality Assessment (NAWQA) Program to provide scientifically sound information for managing the Nation's water resources. The major goals of the NAWQA Program are to assess the status and long-term trends of the Nation's surface- and ground-water quality and to understand the natural and human factors that affect it (Gilliom and others, 1995). In 2001, the NAWQA Program began a second decade of intensive water-quality assessments. The 42 study units for this second decade were selected to represent a wide range of important hydrologic environments and potential contaminant sources. These NAWQA studies continue to address the goals of the first decade of the assessments to determine how water-quality conditions are changing over time. In addition to local- and regional-scale studies, NAWQA began to analyze and synthesize water-quality status and trends at the principal aquifer and major river-basin scales. This fact sheet summarizes results from four NAWQA studies that relate water quality to agricultural chemical use and environmental setting at these various scales: * Comparison of ground-water quality in northern and southern High Plains agricultural settings (principal aquifer scale); * Distribution patterns of pesticides and degradates in rain (local scale); * Occurrence of pesticides in shallow ground water underlying four agricultural areas (local and regional scales); and * Trends in nutrients and sediment over time in the Missouri River and its tributaries (major river-basin scale).

  8. The economic impact of more sustainable water use in agriculture: A computable general equilibrium analysis

    NASA Astrophysics Data System (ADS)

    Calzadilla, Alvaro; Rehdanz, Katrin; Tol, Richard S. J.

    2010-04-01

    SummaryAgriculture is the largest consumer of freshwater resources - around 70 percent of all freshwater withdrawals are used for food production. These agricultural products are traded internationally. A full understanding of water use is, therefore, impossible without understanding the international market for food and related products, such as textiles. Based on the global general equilibrium model GTAP-W, we offer a method for investigating the role of green (rain) and blue (irrigation) water resources in agriculture and within the context of international trade. We use future projections of allowable water withdrawals for surface water and groundwater to define two alternative water management scenarios. The first scenario explores a deterioration of current trends and policies in the water sector (water crisis scenario). The second scenario assumes an improvement in policies and trends in the water sector and eliminates groundwater overdraft world-wide, increasing water allocation for the environment (sustainable water use scenario). In both scenarios, welfare gains or losses are not only associated with changes in agricultural water consumption. Under the water crisis scenario, welfare not only rises for regions where water consumption increases (China, South East Asia and the USA). Welfare gains are considerable for Japan and South Korea, Southeast Asia and Western Europe as well. These regions benefit from higher levels of irrigated production and lower food prices. Alternatively, under the sustainable water use scenario, welfare losses not only affect regions where overdrafting is occurring. Welfare decreases in other regions as well. These results indicate that, for water use, there is a clear trade-off between economic welfare and environmental sustainability.

  9. Agricultural Land Use mapping by multi-sensor approach for hydrological water quality monitoring

    NASA Astrophysics Data System (ADS)

    Brodsky, Lukas; Kodesova, Radka; Kodes, Vit

    2010-05-01

    classified: winter crops, spring crops, oilseed rape, legumes, summer and other crops. This study highlights operational potentials of high temporal full resolution MERIS images in agricultural land use monitoring. Practical application of this methodology is foreseen, among others, in the water quality monitoring. Effective pesticide monitoring relies also on spatial distribution of applied pesticides, which can be derived from crop - plant protection product relationship. Knowledge of areas with predominant occurrence of specific crop based on remote sensing data described above can be used for a forecast of probable plant protection product application, thus cost-effective pesticide monitoring. The remote sensing data used on a continuous basis can be used in other long-term water management issues and provide valuable data for decision makers. Acknowledgement: Authors acknowledge the financial support of the Ministry of Education, Youth and Sports of the Czech Republic (grants No. 2B06095 and No. MSM 6046070901). The study was also supported by ESA CAT-1 (ref. 4358) and SOSI projects (Spatial Observation Services and Infrastructure; ref. GSTP-RTDA-EOPG-SW-08-0004).

  10. Optimal management of water resources demand and supply in irrigated agriculture from plot to regional scale

    NASA Astrophysics Data System (ADS)

    Schütze, Niels; Wagner, Michael

    2016-04-01

    Growing water scarcity in agriculture is an increasing problem in future in many regions of the world. For assessing irrigation as a measure to increase agricultural water security a generalized stochastic optimization framework for a spatial distributed estimation of future irrigation water demand is proposed, which ensures safe yields and a high water productivity at the same time. Different open loop and closed loop control strategies are evaluated within this stochastic optimization framework in order to generate reliable stochastic crop water production functions (SCWPF). The resulting database of SCWPF can serve as a central decision support tool for both, (i) a cost benefit analysis of farm irrigation modernization on a local scale and (ii) a regional water demand management using a multi-scale approach for modeling and implementation. The new approach is applied using the example of a case study in Saxony, which is dealing with the sustainable management of future irrigation water demands and its implementation.

  11. Agriculture and Energy: Implications for Food Security, Water, and Land Use

    NASA Astrophysics Data System (ADS)

    Tokgoz, S.; Zhang, W.; Msangi, S.; Bhandary, P.

    2011-12-01

    Sustainable production of agricultural commodities and growth of international trade in these goods are challenged as never before by supply-side constraints (such as climate change, water and land scarcity, and environmental degradation) and by demand-side dynamics (volatility in food and energy markets, the strengthening food-energy linkage, population growth, and income growth). On the one hand, the rapidly expanding demand can potentially create new market opportunities for agriculture. On the other hand, there are many threats to a sufficient response by the supply side to meet this growing and changing demand. Agricultural production systems in many countries are neither resource-efficient, nor producing according to their full potential. The stock of natural resources such as land, water, nutrients, energy, and genetic diversity is shrinking relative to demand, and their use must become increasingly efficient in order to reduce environmental impacts and preserve the planet's productive capacity. World energy prices have increased rapidly in recent years. At the same time, agriculture has become more energy-intensive. Higher energy costs have pushed up the cost of producing, transporting and processing agricultural commodities, driving up commodity prices. Higher energy costs have also affected water use and availability through increased costs of water extraction, conveyance and desalinization, higher demand for hydroelectric power, and increased cost of subsidizing water services. In the meantime, the development of biofuels has diverted increasing amounts of agricultural land and water resources to the production of biomass-based renewable energy. This more "intensified" linkage between agriculture and energy comes at a time when there are other pressures on the world's limited resources. The related high food prices, especially those in the developing countries, have led to setbacks in the poverty alleviation effort among the global community with more

  12. Agricultural implications of reduced water supplies in the Green and Upper Yellowstone River Basins

    SciTech Connect

    Lansford, R. R.; Roach, F.; Gollehon, N. R.; Creel, B. J.

    1982-02-01

    The growth of the energy sector in the energy-rich but water-restricted Western US has presented a potential conflict with the irrigated agricultural sector. This study measures the direct impacts on farm income and employment resulting from the transfer of water from agriculture to energy in two specific geographical areas - the Green and Upper Yellowstone River Basins. We used a linear programming model to evaluate the impacts of reduced water supplies. Through the use of regional multipliers, we expanded our analysis to include regional impacts. Volume I provides the major analysis of these impacts. Volume II provides further technical data.

  13. Water for Agriculture in a Vulnerable Delta: A Case Study of Indian Sundarban

    NASA Astrophysics Data System (ADS)

    Das, S.; Bhadra, T.; Hazra, S.

    2015-12-01

    Indian Sundarban lies in the south-western part of the Ganges-Brahmaputra Delta and supports a 4.43 million strong population. The agrarian economy of Sundarban is dominated by rainfed subsistence rice farming. Unavailability of upstream fresh water, high salinity of river water of up to 32ppt, soil salinity ranging between 2dSm-1 to 19dSm-1, small land holdings of per capita 840 sq. metre and inadequate irrigation facilities are serious constraints for agricultural production in Sundarban. This paper assesses Cropping Intensity, Irrigation Intensity and Man-Cropland Ratio from Agriculture Census (2010-11) data and estimates the seasonal water demand for agriculture in different blocks of Sundarban. The research exposes the ever increasing population pressure on agriculture with an average Man Cropland Ratio of 1745 person/sq.km. In 2010-2011, the average cropping intensity was 129.97% and the irrigation intensity was 20.40%. The highest cropping and irrigation intensity have been observed in the inland blocks where shallow ground water is available for agriculture on the contrary, the lowest values have been observed in the southern blocks, due to existence of saline shallow ground water. The annual water demand for agriculture in Sundarban has been estimated as 2784 mcm. Available water from 70000 freshwater tanks and around 8000 numbers of shallow tube wells are not sufficient to meet the agricultural water demand. Existing irrigation sources and rainfall of 343 mcm fall far short of the water demand of 382 mcm during peak dry Season. Unavailability of fresh water restricts the food production, which endangers the food security of 87.5% of the people in Sundarban. To ensure the food security in changing climatic condition, expansion of irrigation network and harnessing of new water sources are essential. Large scale rainwater harvesting, rejuvenation and re-connection of disconnected river channels, artificial recharge within shallow aquifer to bring down its

  14. Assessment of rural ground-water contamination by agricultural chemicals in sensitive areas of Michigan

    SciTech Connect

    Ervin, J.L.; Kittleson, K.M.

    1988-04-01

    The vulnerability of drinking-water supplies to agricultural contamination in three Michigan counties is discussed. The results of nitrate and atrazine analysis of drinking water from 38 wells in those 3 counties is described. Widespread nitrate contamination was demonstrated in agricultural areas with vulnerable aquifers. In addition, atrazine, a widely used herbicide was found in 11 of the 38 wells samples, with concentrations and patterns not conforming to findings in other mid-western states. The need for a comprehensive inventory of the ground-water quality in rural areas of Michigan is emphasized in the report, which describes results from the first year of a 2-year study.

  15. 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...

  16. 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...

  17. Spatial Mapping of Agricultural Water Productivity Using the SWAT Model

    NASA Astrophysics Data System (ADS)

    Thokal, Rajesh Tulshiram; Gorantiwar, S. D.; Kothari, Mahesh; Bhakar, S. R.; Nandwana, B. P.

    2015-03-01

    The Sina river basin is facing both episodic and chronic water shortages due to intensive irrigation development. The main objective of this study was to characterize the hydrologic processes of the Sina river basin and assess crop water productivity using the distributed hydrologic model, SWAT. In the simulation year (1998-1999), the inflow to reservoir from upstream side was the major contributor to the reservoir accounting for 92 % of the total required water release for irrigation purpose (119.5 Mm3), while precipitation accounted for 4.1 Mm3. Annual release of water for irrigation was 119.5 Mm3 out of which 54 % water was diverted for irrigation purpose, 26 % was wasted as conveyance loss, average discharge at the command outlet was estimated as 4 % and annual average ground-water recharge coefficient was in the range of 13-17 %. Various scenarios involving water allocation rule were tested with the goal of increasing economic water productivity values in the Sina Irrigation Scheme. Out of those, only most benefited allocation rule is analyzed in this paper. Crop yield varied from 1.98 to 25.9 t/ha, with the majority of the area between 2.14 and 2.78 t/ha. Yield and WP declined significantly in loamy soils of the irrigation command. Crop productivity in the basin was found in the lower range when compared with potential and global values. The findings suggested that there was a potential to improve further. Spatial variations in yield and WP were found to be very high for the crops grown during rabi season, while those were low for the crops grown during kharif season. The crop yields and WP during kharif season were more in the lower reach of the irrigation commands, where loamy soil is more concentrated. Sorghum in both seasons was most profitable. Sorghum fetched net income fivefold that of sunflower, two and half fold of pearl millet and one and half fold of mung beans as far as crop during kharif season were concerned and it fetched fourfold that of

  18. 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

  19. Analysis of economic impacts of climate change on agricultural water management in Europe

    NASA Astrophysics Data System (ADS)

    Garrote, Luis; Iglesias, Ana

    2016-04-01

    This contribution presents an analysis of impacts of climate change on agricultural water management in Europe. The analysis of climate change impacts on agriculture is composed of two main categories: rainfed agriculture and irrigated agriculture. Impacts on rainfed agriculture are mostly conditioned by climatic factors and were evaluated through the estimation of changes in agricultural productivity induced by climatic changes using the SARA model. At each site, process-based crop responses to climate and management are simulated by using the DSSAT crop models for cereals (wheat and rice), coarse grains (maize) and leguminous (soybeans). Changes in the rest of the crops are derived from analogies to these main crops. For each of the sites we conducted a sensitivity analysis to environmental variables (temperature, precipitation and CO2 levels) and management variables (planting date, nitrogen and irrigation applications) to obtain a database of crop responses. The resulting site output was used to define statistical models of yield response for each site which were used to obtain estimates of changes in agricultural productivity of representative production systems in European agro-climatic regions. Impacts on irrigated agriculture are mostly conditioned by water availability and were evaluated through the estimation of changes in water availability using the WAAPA model, which simulates the operation of a water resources system to maximize water availability. Basic components of WAAPA are inflows, reservoirs and demands. These components are linked to nodes of the river network. WAAPA allows the simulation of reservoir operation and the computation of supply to demands from a system of reservoirs accounting for ecological flows and evaporation losses. WAAPA model was used to estimate maximum potential water availability in the European river network applying gross volume reliability as performance criterion. Impacts on agricultural production are also dependent

  20. Price elasticity reconsidered: Panel estimation of an agricultural water demand function

    NASA Astrophysics Data System (ADS)

    Schoengold, Karina; Sunding, David L.; Moreno, Georgina

    2006-09-01

    Using panel data from a period of water rate reform, this paper estimates the price elasticity of irrigation water demand. Price elasticity is decomposed into the direct effect of water management and the indirect effect of water price on choice of output and irrigation technology. The model is estimated using an instrumental variables strategy to account for the endogeneity of technology and output choices in the water demand equation. Estimation results indicate that the price elasticity of agricultural water demand is -0.79, which is greater than that found in previous studies.

  1. Climate change impacts on global agricultural water deficit

    NASA Astrophysics Data System (ADS)

    Zhang, Xiao; Cai, Ximing

    2013-03-01

    This paper assesses the change in crop water deficits (the difference between crop evapotranspiration and precipitation that is effective for crop growth) of 26 crops (including rainfed and irrigated) under current (1961-1990) and projected climates (2070-2099). We found that despite the universally rising mean temperature, crop water deficits are likely to decline slightly at the global scale, although changes vary by region. While the increasing precipitation and changing intra-annual precipitation distribution in many areas can lead to more effective rainfall for crop growth, the declining diurnal temperature range will play a key role in offsetting the warming effect at the global scale. Regionally, Africa and China are likely to benefit from lower water requirements, but the impacts on other regions, including Europe, India, South America, and the United States, are subject to the land-use types (rainfed or irrigated) and the uncertainty involved in the assessment approaches.

  2. Managing the drinking water catchment areas: the French agricultural cooperatives feed back.

    PubMed

    Charrière, Séverine; Aumond, Claire

    2016-06-01

    The quality of raw water is problematic in France, largely polluted by nitrates and pesticides (Mueller and Helsel, Nutrients in the nation's waters-too much of a good thing? Geological Survey (U.S.), 1996; European Environment Agency, European waters-assessment of status and pressures, 2012).This type of pollution, even though not always due to agriculture (example of the catchment of Ambleville, county 95, France where the nitrate pollution is mainly due to sewers (2012)), has been largely related to the agricultural practices (Sci Total Environ 407:6034-6043, 2009).Taking note of this observation, and instead of letting it paralyze their actions, the agricultural cooperatives decided with Agrosolutions to act directly on the field with their subscribers to change the agricultural practices impacting the water and the environment.This article shows how the French agricultural cooperatives transformed the awareness of the raw water quality problem into an opportunity for the development and implementation of more precise and responsible practices, to protect their environment. They measure in order to pilot, co-construct and build the best action plans possible according to the three pillars of environment, economy and agronomy.

  3. Managing the drinking water catchment areas: the French agricultural cooperatives feed back.

    PubMed

    Charrière, Séverine; Aumond, Claire

    2016-06-01

    The quality of raw water is problematic in France, largely polluted by nitrates and pesticides (Mueller and Helsel, Nutrients in the nation's waters-too much of a good thing? Geological Survey (U.S.), 1996; European Environment Agency, European waters-assessment of status and pressures, 2012).This type of pollution, even though not always due to agriculture (example of the catchment of Ambleville, county 95, France where the nitrate pollution is mainly due to sewers (2012)), has been largely related to the agricultural practices (Sci Total Environ 407:6034-6043, 2009).Taking note of this observation, and instead of letting it paralyze their actions, the agricultural cooperatives decided with Agrosolutions to act directly on the field with their subscribers to change the agricultural practices impacting the water and the environment.This article shows how the French agricultural cooperatives transformed the awareness of the raw water quality problem into an opportunity for the development and implementation of more precise and responsible practices, to protect their environment. They measure in order to pilot, co-construct and build the best action plans possible according to the three pillars of environment, economy and agronomy. PMID:27074925

  4. Participatory geographic information systems for agricultural water management scenario development: A Tanzanian case study

    NASA Astrophysics Data System (ADS)

    Cinderby, Steve; Bruin, Annemarieke de; Mbilinyi, Boniface; Kongo, Victor; Barron, Jennie

    One of the keys to environmental management is to understand the impact and interaction of people with natural resources as a means to improve human welfare and the consequent environmental sustainability for future generations. In terms of water management one of the on-going challenges is to assess what impact interventions in agriculture, and in particularly different irrigation strategies, will have on livelihoods and water resources in the landscape. Whilst global and national policy provide the overall vision of desired outcomes for environmental management, agricultural development and water use strategies they are often presented with local challenges to embed these policies in the reality on the ground, with different stakeholder groups. The concept that government agencies, advocacy organizations, and private citizens should work together to identify mutually acceptable solutions to environmental and water resource issues is increasing in prominence. Participatory spatial engagement techniques linked to geographic information systems (commonly termed participatory GIS (PGIS)) offers one solution to facilitate such stakeholder dialogues in an efficient and consultative manner. In the context of agricultural water management multi-scale PGIS techniques have recently been piloted as part of the ‘Agricultural Water Management Solutions’ project to investigate the current use and dependencies of water by small-holder farmers a watershed in Tanzania. The piloted approach then developed PGIS scenarios describing the effects on livelihoods and water resources in the watershed when introducing different management technologies. These relatively rapid PGIS multi-scale methods show promise for assessing current and possible future agriculture water management technologies in terms of their bio-physical and socio-economic impacts at the watershed scale. The paper discusses the development of the methodology in the context of improved water management decision

  5. 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

  6. 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

  7. Relations between retired agricultural land, water quality, and aquatic-community health, Minnesota River Basin

    USGS Publications Warehouse

    Christensen, Victoria G.; Lee, Kathy E.; McLees, James M.; Niemela, Scott L.

    2012-01-01

    The relative importance of agricultural land retirement on water quality and aquatic-community health was investigated in the Minnesota River Basin. Eighty-two sites, with drainage areas ranging from 4.3 to 2200 km2, were examined for nutrient concentrations, measures of aquatic-community health (e.g., fish index of biotic integrity [IBI] scores), and environmental factors (e.g., drainage area and amount of agricultural land retirement). The relation of proximity of agricultural land retirement to the stream was determined by calculating the land retirement percent in various riparian zones. Spearman's rho results indicated that IBI score was not correlated to the percentage of agricultural land retirement at the basin scale (p = 0.070); however, IBI score was correlated to retired land percentage in the 50- to 400-m riparian zones surrounding the streams (p < 0.05), indicating that riparian agricultural land retirement may have more influence on aquatic-community health than does agricultural land retirement in upland areas. Multivariate analysis of covariance and analysis of covariance models indicated that other environmental factors (such as drainage area and lacustrine and palustrine features) commonly were correlated to aquatic-community health measures, as were in-stream factors (standard deviation of water depth and substrate type). These results indicate that although agricultural land retirement is significantly related to fish communities as measured by the IBI scores, a combination of basin, riparian, and in-stream factors act together to influence IBI scores.

  8. Optimizing the use of limited water in agricultural systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    About 92% of freshwater withdrawals in Uzbekistan are used for irrigation, whereas in the United States, freshwater withdrawls account for about 33% of the total use. In Uzbekistan, most of the water suitable for irrigation has already been allocated. In the United States, groundwater depletion and ...

  9. Summary of reported agriculture and irrigation water use in Phillips County, Arkansas, 1991

    USGS Publications Warehouse

    Holland, T.W.; Manning, C.A.; Stafford, K.L.

    1993-01-01

    This report summarizes the 1991 water-use reporting through the Conservation District Office in Phillips County, Arkansas. The number of withdrawal registrations for Phillips County was 1,109 (1,103 groundwater and 6 surface water). Water withdrawals reported during the registration process total 0.15 Mgal/d (0.15 Mgal/d groundwater and none from surface water) for agriculture and 123.75 Mgal/d (122.66 Mgal/d groundwater and 1.09 Mgal/d surface water) for irrigation. The registration reports for 1991 indicate that this water was applied to 96,502 acres of land to irrigate wheat, rice, corn, soybeans, milo, cotton, hay, vegetables, grapes, nuts, fruit trees, and sod, as well as for the agricultural use of animal aquaculture.

  10. Summary of reported agriculture and irrigation water use in Lee County, Arkansas, 1991

    USGS Publications Warehouse

    Holland, T.W.; Manning, C.A.; Stafford, K.L.

    1993-01-01

    This report summarizes the 1991 water-use reporting through the Conservation District Office in Lee County, Arkansas. The number of withdrawal registrations for Lee County was 1,582 (1,533 groundwater and 49 surface water). Water withdrawals reported during the registration process total 3.77 Mgal/d (3.39 Mgal/d groundwater and 0.38 Mgal/d surface water) for agriculture and 169.25 Mgal/d (166.79 Mgal/d groundwater and 2.46 Mgal/d surface water) for irrigation. The registration reports for 1991 indicate that this water was applied to 97,029 acres of land to irrigate wheat, rice, corn, soybeans, milo, cotton, hay, vegetables, and nuts as well as for the agricultural uses of animal aquaculture and ducks.

  11. Summary of reported agriculture and irrigation water use in Crittendon County, Arkansas, 1991

    USGS Publications Warehouse

    Holland, T.W.; Manning, C.A.

    1991-01-01

    This report summarizes the 1991 water-use reporting through the Conservation District Office in Crittenden County, Arkansas. The number of withdrawal registrations for Crittenden County was 868 (824 groundwater and 44 surface water). Water withdrawals reported during the registration process total 0.67 Mgal/d (0.67 Mgal/d groundwater and none from surface water) for agriculture and 60.29 Mgal/d (59.15 Mgal/d groundwater and 1.14 Mgal/d surface water) for irrigation. The registration reports for 1991 indicate that this water applied to 51,937 acres of land to irrigate wheat, rice, corn, soybeans, milo, cotton, and hay as well as for the agricultural uses of animal aquaculture.

  12. Summary of reported agriculture and irrigation water use in Woodruff County, Arkansas, 1991

    USGS Publications Warehouse

    Holland, T.W.; Manning, C.A.; Stafford, K.L.

    1993-01-01

    This report summarizes the 1991 water-use reporting through the Conservation District Office in Woodruff County, Arkansas. The number of withdrawal registrations for Woodruff County was 1,930 (1,755 groundwater and 175 surface water). Water withdrawals reported during the registration process total 0.91 Mgal/d (0.91 Mgal/d groundwater and none from surface water) for agriculture and 284.20 Mgal/d (258.13 Mgal/d groundwater and 26.07 Mgal/d surface water) for irrigation. The registration reports for 1991 indicate that this water was applied to 138,452 acres of land to irrigate wheat, rice, corn, soybeans, milo, cotton, and vegetables, as well as for the agricultural uses of animal aquaculture and ducks.

  13. Summary of reported agriculture and irrigation water use in Drew County, Arkansas, 1991

    USGS Publications Warehouse

    Holland, T.W.; Manning, C.A.

    1993-01-01

    This report summarizes the 1991 water-use reporting through the Conservation District Office in Drew County, Arkansas. The number of withdrawal registrations for Drew County was 505 (342 groundwater and 163 surface water). Water withdrawals reported during the registration process total 0.32 Mgal/d (0.32 Mgal/d groundwater and none from surface water) for agriculture and 43.04 Mgal/d (37.43 Mgal/d groundwater and 5.61 Mgal/d surface water) for irrigation. The registration reports for 1991 indicate that this water was applied to 23,775 acres of land to irrigate wheat, rice, corn, soybeans, milo, cash grains, cotton, and hay as well as for the agricultural use of animal aquaculture and catfish.

  14. Summary of reported agriculture and irrigation water use in Lincoln County, Arkansas, 1991

    USGS Publications Warehouse

    Holland, T.W.; Manning, C.A.; Stafford, K.L.

    1993-01-01

    This report summarizes the 1991 water-use reporting through the Conservation District Office in Lincoln County, Arkansas. The number of withdrawal registrations for Lincoln County was 1,167 (868 groundwater and 299 surface water). Water with- drawals reported during the registration process total 3.88 Mgal/d (3.88 Mgal/d groundwater and none from surface water) for agriculture and 114.31 Mgal/d (98.59 Mgal/d groundwater and 15.72 Mgal/d surface water) for irrigation. The registration reports for 1991 indicate that this water was applied to 81,477 acres of land to irrigate rice, corn, soybeans, milo, cotton and vegetables as well as for the agricultural use of animal aquaculture.

  15. Summary of reported agriculture and irrigation water use in St. Francis County, Arkansas, 1991

    USGS Publications Warehouse

    Holland, T.W.; Manning, C.A.; Stafford, K.L.

    1993-01-01

    This report summarizes the 1991 water-use reporting through the Conservation District Office in St. Francis County, Arkansas. The number of withdrawal registrations for St. Francis County was 1,286 (1,194 groundwater and 92 surface water). Water withdrawals reported during the registration process total 0.14 Mgal/d (0.14 Mgal/d groundwater and none from surface water) for agriculture and 172.48 Mgal/d groundwater and 12.66 Mgal/d surface water) for irrigation. The registration reports for 1991 indicate that this water was applied to 100,183 acres of land to irrigate rice, soybeans, milo, cotton, and vegetables as well as for the agricultural uses of animal aquaculture and ducks.

  16. Summary of reported agriculture and irrigation water use in Clay County, Arkansas, 1991

    USGS Publications Warehouse

    Holland, T.W.; Manning, C.A.

    1993-01-01

    This report summarizes the 1991 water-use reporting through the Conservation District Office in Clay County, Arkansas. The number of withdrawal registrations for Clay County was 2,025 (1,965 groundwater and 60 surface water). Water withdrawals reported during the registration process total 2.07 Mgal/d (2.01 Mgal/d groundwater and 0.06 Mgal/d surface water) for agriculture and 164.50 Mgal/d (159.64 Mgal/d groundwater and 4.56 Mgal/d surface water) for irrigation. The registration reports for 1991 indicate that this water was applied to 94,399 acres of land to irrigate rice, corn, soybeans, milo, cotton, vegetables, and unknown crops as well as for the agricultural uses of animal aquaculture.

  17. Summary of reported agriculture and irrigation water use in Mississippi County, Arkansas, 1991

    USGS Publications Warehouse

    Holland, T.W.; Manning, C.A.; Stafford, K.L.

    1993-01-01

    This report summarizes the 1991 water-use reporting through the Conservation District Office in Mississippi County, Arkansas. The number of withdrawal registrations for Mississippi County was 981 (946 groundwater and 35 surface water). Water withdrawals reported during the registration process total 0.06 Mgal/d (0.01 Mgal/d groundwater and 0.05 Mgal/d surface water) for agriculture and 97.82 Mgal/d (94.16 Mgal/d groundwater and 3.66 Mgal/d surface water) for irrigation. The registration reports for 1991 indicate that this water was applied to 109,345 acres of land to irrigate rice, corn, soybeans, milo, cotton, hay, vegetables, berries, and sod as well as for the agricultural use of animal aquaculture.

  18. Summary of reported agriculture and irrigation water use in Craighead County, Arkansas, 1991

    USGS Publications Warehouse

    Holland, T.W.; Manning, C.A.

    1993-01-01

    This report summarizes the 1991 water-use reporting through the Conservation District Office in Craighead County, Arkansas. The number of withdrawal registrations for Craighead County was 2,384 (2,187 groundwater and 197 surface water). Water withdrawals reported during the registration process total 1.45 Mgal/d (0.50 Mgal/d groundwater and 0.95 Mgal/d surface water) for agriculture and 287.20 Mgal/d (261.52 Mgal/d groundwater and 25.68 Mgal/d surface water) for irrigation. The registration reports for 1991 indicate that this water was applied to 168,003 acres of land to irrigate rice, sorghum, corn, soybeans, milo, cotton, hay, vegetables, nuts, and sod as well as for the agricultural uses of animal aquaculture and sports clubs.

  19. Summary of reported agriculture and irrigation water use in Lonoke County, Arkansas, 1991

    USGS Publications Warehouse

    Holland, T.W.; Manning, C.A.; Stafford, K.L.

    1993-01-01

    This report summarizes the 1991 water-use reporting through the Conservation District Office in Lonoke County, Arkansas. The number of withdrawal registrations for Lonoke County was 3,313 (2,587 groundwater and 726 surface water). Water with drawals reported during the registration process total 61.30 Mgal/d (59.50 Mgal/d groundwater and 1.80 Mgal/d surface water) for agriculture and 300.45 Mgal/d (241.86 Mgal/d groundwater and 58.59 Mgal/d surface water) for irrigation. The registra- tion reports for 1991 indicate that this water was applied to 238,457 acres of land to irrigate rice, sorghum, corn, soybeans, milo, cash grains, cotton, and sod as well as for the agricultural uses of animal aquaculture, hatcheries, and ducks.

  20. Summary of reported agriculture and irrigation water use in west-central Arkansas counties, 1991

    USGS Publications Warehouse

    Holland, T.W.; Manning, C.A.; Stafford, K.L.

    1993-01-01

    This report summarizes the 1991 water-use reporting through the Conservation District Offices in the following west-central Arkansas counties: Conway, Crawford, Faulkner, Franklin, Johnson, Logan, Perry, Pope, Scott, Sebastian, and Yell. The number of withdrawal registrations for west-central Arkansas counties was 307 (90 groundwater and 217 surface water). Water withdrawals reported during the registration process total 1.00 Mgal/d (0.15 Mgal/d groundwater and 0.85 Mgal/d surface water) for agriculture and 32.07 Mgal/d (5.67 Mgal/d groundwater and 26.40 Mgal/d surface water) for irrigation. The registration reports for 1991 indicate that this water was applied to 22,856 acres of land to irrigate rice, corn, sorghum, soybeans, wheat, cash grains, hay, milo, vegetables, sod, berries, grapes, and fruit trees as well as for the agricultural uses of catfish and ducks.

  1. Summary of reported agriculture and irrigation water use in White County, Arkansas, 1991

    USGS Publications Warehouse

    Holland, T.W.; Manning, C.A.; Stafford, K.L.

    1993-01-01

    This report summarizes the 1991 water-use reporting through the Conservation District Office in White County, Arkansas. The number of withdrawal registrations for White County was 1,365 (1,146 groundwater and 219 surface water). Water withdrawals reported during the registration process total 1.37 Mgal/d (0.95 Mgal/d groundwater and 0.42 Mgal/d surface water) for agriculture and 69.91 Mgal/d (43.78 Mgal/d groundwater and 26.13 Mgal/d surface water) for irrigation. The registration reports for 1991 indicate that this water was supplied to 46,315 acres of land to irrigate rice, sorghum, corn, soybeans, milo, cash grains, hay, vegetables, berries, grapes, fruit trees, sod, and unknown crop as well as for the agricultural uses of animal aquaculture, minnows, ducks, and sport clubs.

  2. Summary of reported agriculture and irrigation water use in Cross County, Arkansas, 1991

    USGS Publications Warehouse

    Holland, T.W.; Manning, C.A.

    1993-01-01

    This report summarizes the 1991 water-use reporting through the Conservation District Office in Cross County, Arkansas. The number of withdrawal registrations for Cross County was 2,506 (2,314 groundwater and 192 surface water). Water withdrawals reported during the registration process total 2.01 Mgal/d (1.85 Mgal/d groundwater and 0.16 Mgal/d surface water) for agriculture and 404.04 Mgal/d (377.08 Mgal/d groundwater and 26.96 Mgal/d surface water) for irrigation. The registration reports for 1991 indicate that this water was applied to 218,152 acres of land to irrigate rice, sorghum, corn, soybeans, milo, cash grains, cotton, hay, and vegetables as well as for the agricultural use of animal aquaculture and ducks.

  3. Summary of reported agriculture and irrigation water use in Pulaski County, Arkansas, 1991

    USGS Publications Warehouse

    Holland, T.W.; Manning, C.A.; Stafford, K.L.

    1993-01-01

    This report summarizes the 1991 water-use reporting through the Conservation District Office in Pulaski County, Arkansas. The number of withdrawal registrations for Pulaski County was 291 (170 groundwater and 121 surface water). Water withdrawals reported during the registration process total 0.91 Mgal/d (0.71 Mgal/d groundwater and 0.20 Mgal/d surface water) for agriculture and 37.42 Mgal/d (28.53 Mgal/d groundwater and 8.89 Mgal/d surface water) for irrigation. The registration reports for 1991 indicate that this water was applied to 28,088 acres of land to irrigate wheat, rice, sorghum, corn, soybeans, milo, cash grains, cotton, vegetables, and sod, as well as for the agricultural uses of animal aquaculture, timber, and ducks.

  4. Summary of reported agriculture and irrigation water use in southwestern Arkansas counties, 1991

    USGS Publications Warehouse

    Holland, T.W.; Manning, C.A.; Stafford, K.L.

    1993-01-01

    This report summarizes the 1991 water-use reporting through the Conservation District Offices in the following southwestern Arkansas counties: Bradley, Calhoun, Clark, Cleveland, Columbia, Dallas, Garland, Grant, Hempstead, Hot Spring, Howard, Little River, Montgomery, Nevada, Ouachita, Pike, Polk, Saline, Sevier, and Union. The number of withdrawal registrations for southwestern Arkansas counties was 132 (31 groundwater and 101 surface water). Water withdrawals reported during the registration process total 0.84 Mgal/d (none from groundwater and 0.84 Mgal/d surface water) for agriculture and 14.22 Mgal/d (1.64 Mgal/d groundwater and 12.58 Mgal/d surface water) for irrigation. The registration reports for 1991 indicate that this water was applied to 8,455 acres of land to irrigate rice, corn, sorghum, soybeans, cotton, cash grains, vegetables, sod, berries, fruit trees, timber, shrubs, and nuts as well as for the agricultural use of animal aquaculture.

  5. Summary of reported agriculture and irrigation water use in Prairie County, Arkansas, 1991

    USGS Publications Warehouse

    Holland, T.W.; Manning, C.A.; Stafford, K.L.

    1993-01-01

    This report summarizes the 1991 water-use reporting through the Conservation District Office in Prairie County, Arkansas. The number of withdrawal registrations for Prairie County was 2,187 (1,786 groundwater and 401 surface water). Water with- drawals reported during the registration process total 26.93 Mgal/d (26.84 Mgal/d groundwater and 0.09 Mgal/d surface water) for agriculture and 191.08 Mgal/d (138.79 Mgal/d groundwater and 52.29 Mgal/d surface water) for irrigation. The registration reports for 1991 indicate that this water was applied to 144,956 acres of land to irrigate rice, corn, soybeans, milo, cash grains, unknown crop, cotton hay, berries, and fruit trees as well as for the agricultural uses of animal aquaculture, minnows, timber, and ducks.

  6. Summary of reported agriculture and irrigation water use in northwestern Arkansas counties, 1991

    USGS Publications Warehouse

    Holland, T.W.; Manning, C.A.; Stafford, K.L.

    1993-01-01

    This report summarizes the 1991 water-use reporting through the Conservation District Offices in the following northwestern Arkansas counties: Baxter, Benton, Boone, Carroll, Cleburne, Fulton, Izard, Madison, Marion, Newton, Searcy, Sharp, Stone, Van Buren, and Washington. The number of withdrawal registrations for northwestern Arkansas counties was 106 (16 groundwater and 90 surface water). Water withdrawals reported during the registration process total 41.72 Mgal/d (0.74 Mgal/d groundwater and 40.98 Mgal/d surface water) for agriculture and 3.33 Mgal/d (0.27 Mgal/d groundwater and 3.06 Mgal/d surface water) for irrigation. The registration reports for 1991 indicate that this water was applied to 3,588 acres of land to irrigate rice, soybeans, cash grains, hay, oats, vegetables, sod, berries, fruit trees, and timber as well as for the agricultural use of animal aquaculture.

  7. Summary of reported agriculture and irrigation water use in Greene County, Arkansas, 1991

    USGS Publications Warehouse

    Holland, T.W.; Manning, C.A.; Stafford, K.L.

    1993-01-01

    This report summarizes the 1991 water-use reporting through the Conservation District Office in Greene County, Arkansas. The number of withdrawal registrations for Greene County was 1,567 (1,510 groundwater and 57 surface water). Water withdrawals reported during the registration process total 26.69 Mgal/d (23.98 Mgal/d groundwater and 2.71 Mgal/d surface water) for agriculture and 92.46 Mgal/d (91.03 Mgal/d groundwater and 1.43 Mgal/d surface water) for irrigation. The registration reports for 1991 indicate that this water was applied to 70,947 acres of land to irrigate rice, corn, soybeans, milo, cotton, fruit trees, and sod as well as for the agricultural use of animal aquaculture.

  8. Summary of reported agriculture and irrigation water use in Jackson County, Arkansas, 1991

    USGS Publications Warehouse

    Holland, T.W.; Manning, C.A.; Stafford, K.L.

    1993-01-01

    This report summarizes the 1991 water-use reporting through the Conservation District Office in Jackson County, Arkansas. The number of withdrawal registrations for Jackson County was 2,450 (2,279 groundwater and 171 surface water). Water withdrawals reported during the registration process total 5.24 Mgal/d (4.81 Mgal/d groundwater and 0.43 Mgal/d surface water) for agriculture and 274.90 Mgal/d (263.59 Mgal/d groundwater and 11.31 Mgal/d surface water) for irrigation. The registration reports for 1991 indicate that this water was applied to 149,737 acres of land to irrigate rice, corn, soybeans, milo, cash grains, cotton, hay, and vegetables as well as for the agricultural use of animal aquaculture, goldfish, and ducks.

  9. Spatially continuous interpolation of water stage and water depths using the Everglades depth estimation network (EDEN)

    USGS Publications Warehouse

    Pearlstine, Leonard; Higer, Aaron; Palaseanu, Monica; Fujisaki, Ikuko; Mazzotti, Frank

    2007-01-01

    The Everglades Depth Estimation Network (EDEN) is an integrated network of real-time water-level monitoring, ground-elevation modeling, and water-surface modeling that provides scientists and managers with current (2000-present), online water-stage and water-depth information for the entire freshwater portion of the Greater Everglades. Continuous daily spatial interpolations of the EDEN network stage data are presented on a 400-square-meter grid spacing. EDEN offers a consistent and documented dataset that can be used by scientists and managers to (1) guide large-scale field operations, (2) integrate hydrologic and ecological responses, and (3) support biological and ecological assessments that measure ecosystem responses to the implementation of the Comprehensive Everglades Restoration Plan (CERP) The target users are biologists and ecologists examining trophic level responses to hydrodynamic changes in the Everglades.

  10. 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.

  11. 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.

  12. Improving soil moisture simulation to support Agricultural Water Resource Management using Satellite-based water cycle observations

    NASA Astrophysics Data System (ADS)

    Gupta, Manika; Bolten, John; Lakshmi, Venkat

    2016-04-01

    Efficient and sustainable irrigation systems require optimization of operational parameters such as irrigation amount which are dependent on the soil hydraulic parameters that affect the model's accuracy in simulating soil water content. However, it is a scientific challenge to provide reliable estimates of soil hydraulic parameters and irrigation estimates, given the absence of continuously operating soil moisture and rain gauge network. For agricultural water resource management, the in-situ measurements of soil moisture are currently limited to discrete measurements at specific locations, and such point-based measurements do not represent the spatial distribution at a larger scale accurately, as soil moisture is highly variable both spatially and temporally (Wang and Qu 2009). In the current study, flood irrigation scheme within the land surface model is triggered when the root-zone soil moisture deficit reaches below a threshold of 25%, 50% and 75% with respect to the maximum available water capacity (difference between field capacity and wilting point) and applied until the top layer is saturated. An additional important criterion needed to activate the irrigation scheme is to ensure that it is irrigation season by assuming that the greenness vegetation fraction (GVF) of the pixel exceed 0.40 of the climatological annual range of GVF (Ozdogan et al. 2010). The main hypothesis used in this study is that near-surface remote sensing soil moisture data contain useful information that can describe the effective hydrological conditions of the basin such that when appropriately inverted, it would provide field capacity and wilting point soil moisture, which may be representative of that basin. Thus, genetic algorithm inverse method is employed to derive the effective parameters and derive the soil moisture deficit for the root zone by coupling of AMSR-E soil moisture with the physically based hydrological model. Model performance is evaluated using MODIS

  13. Increasing the potential of agricultural water harvesting in Africa

    NASA Astrophysics Data System (ADS)

    Irvine, Brian; Kirkby, Mike; Woldearegay, Kifle

    2014-05-01

    The WAHARA project aims to increase the potential of water harvesting in Africa. The WAHARA project draws on expertise and field data from four study sites in Ethiopia, Tunisia, Burkina Faso and Zambia. The project is transdisciplinary working closely with stakeholders to ensure that the water harvesting technologies selected and tested meet their needs. The effectiveness of WH technologies will be assessed under different environmental and socio-economic conditions. Each study site offers a number of WH technologies and aim to trial technologies from other study sites. The results from the study sites will inform the adaptation of the PESERA model and the potential of WH for the whole of Africa This presentation highlights the climate range in which the field trials are being carried out and the technologies being trialed in northern Ethiopia. Conceptual models for each technology are considered and incorporated into the PESERA model. The model is applied for the study site with both field based and catchment based technologies being assessed. The transferability and potential of individual and combined technologies will be considered across climate gradients and soil type for Africa. A quick assessment tool has been developed and offers an initial assessment of water harvesting potential. The tool can be used to quickly assess which kinds of WHT could be used in specific areas in Africa and is available to interested parties.

  14. Integrated management of water resources demand and supply in irrigated agriculture from plot to regional scale

    NASA Astrophysics Data System (ADS)

    Schütze, Niels; Wagner, Michael

    2016-05-01

    Growing water scarcity in agriculture is an increasing problem in future in many regions of the world. Recent trends of weather extremes in Saxony, Germany also enhance drought risks for agricultural production. In addition, signals of longer and more intense drought conditions during the vegetation period can be found in future regional climate scenarios for Saxony. However, those climate predictions are associated with high uncertainty and therefore, e.g. stochastic methods are required to analyze the impact of changing climate patterns on future crop water requirements and water availability. For assessing irrigation as a measure to increase agricultural water security a generalized stochastic approach for a spatial distributed estimation of future irrigation water demand is proposed, which ensures safe yields and a high water productivity at the same time. The developed concept of stochastic crop water production functions (SCWPF) can serve as a central decision support tool for both, (i) a cost benefit analysis of farm irrigation modernization on a local scale and (ii) a regional water demand management using a multi-scale approach for modeling and implementation. The new approach is applied using the example of a case study in Saxony, which is dealing with the sustainable management of future irrigation water demands and its implementation.

  15. Relation of nitrate concentrations in water to agricultural land use and soil type in Dakota County, Minnesota, 1990

    USGS Publications Warehouse

    Almendinger, James Edward

    1991-01-01

    Nitrate is commonly found in ground water in agricultural areas throughout the Midwest. The emphasis of this report is to relate differences in nitrate concentrations in ground water to agricultural land use and soil type. In addition, nitrate concentrations in streams, shallow ground water near the water table, and deeper ground water from 10 to 30 feet below the water table are tabulated for selected sites in Dakota County.

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

    NASA Astrophysics Data System (ADS)

    Scanlon, Bridget R.; Jolly, Ian; Sophocleous, Marios; Zhang, Lu

    2007-03-01

    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.

  17. 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.

  18. Measuring environmental efficiency of agricultural water use: a Luenberger environmental indicator.

    PubMed

    Azad, Md A S; Ancev, Tihomir

    2014-12-01

    Irrigated agriculture creates substantial environmental pressures by withdrawing large quantities of water, leaving rivers and wetlands empty and unable to support the valuable ecosystems that depend on the water resource. The key challenge facing society is that of balancing water extractions for agricultural production and other uses with provision of appropriate environmental flow to maintain healthy rivers and wetlands. Measuring tradeoffs between economic gain of water use in agriculture and its environmental pressures can contribute to constructing policy instruments for improved water resource management. The aim of this paper is to develop a modelling framework to measure these tradeoffs. Using a new approach - Luenberger environmental indicator - the study derives environmental efficiency scores for various types of irrigation enterprises across seventeen natural resource management regions within the Murray-Darling Basin, Australia. Findings show that there is a substantial variation in environmental performance of irrigation enterprises across the regions. Some enterprises were found to be relatively environmentally efficient in some regions, but they were not efficient in others. The environmental efficiency scores could be used as a guideline for formulating regional policy and strategy to achieve sustainable water use in the agricultural sector. PMID:25103337

  19. Improving Spatial Resolution of Agricultural Water Use Estimation Using ALOS AVNIR-2 Imagery

    NASA Astrophysics Data System (ADS)

    Alexandridis, T. K.; Chemin, Y.; Cherif, I.; Tsakoumis, G.; Galanis, G.; Arampatzis, G.; Zalidis, G. C.; Silleos, N. G.; Stavrinos, E.

    2008-11-01

    Estimating agricultural water use is an issue of primary importance in the Mediterranean. At the same time, several advanced algorithms have been developed, which couple Earth Observation data in thermal, visible and near-infrared wavelengths with a few meteorological measurements to provide a close approximation to the actual water use. However, due to the detailed cropping pattern of the Greek agricultural landscape, higher resolution satellite imagery is necessary, a demand which may not be met by the available thermal infrared imagery (Landsat 5 TM and Terra/ASTER). This study investigates the contribution of ALOS AVNIR-2 images to estimate agricultural water consumption in high spatial resolution. Two methods were tested, the Surface Energy Balance Algorithm for Land and the remote sensing crop coefficient method. The results were compared against similar products derived with Terra/MODIS and Landsat TM images, used as reference. Comparisons were based on a pixel level, with a random dataset for pixel to pixel comparison and on a canal command area level, with statistical comparison of the water use estimations. Merging of the two datasets was based on the modified Brovey technique, which has the advantage of maintaining the original values, but redistributes them in a higher resolution space. Concluding, ALOS AVNIR-2 significantly underestimated agricultural water use with the crop coefficient method, but was successful in providing the element of high spatial detail to the MODIS derived result, proving to be a useful input in modelling water use of irrigated Greek basins.

  20. 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

  1. 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.

  2. 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.

  3. Water Resources Data, Georgia, 2002--Volume 1: Continuous water-level, streamflow, water-quality data, and periodic water-quality data, Water Year 2002

    USGS Publications Warehouse

    Hickey, Andrew C.; Kerestes, John F.; McCallum, Brian E.

    2002-01-01

    Water resources data for the 2002 water year for Georgia consists of records of stage, discharge, and water quality of streams; and the stage and contents of lakes and reservoirs published in two volumes in a digital format on a CD-ROM. Volume one of this report contains water resources data for Georgia collected during water year 2002, including: discharge records of 154 gaging stations; stage for 165 gaging stations; precipitation for 105 gaging stations; information for 20 lakes and reservoirs; continuous water-quality records for 27 stations; the annual peak stage and annual peak discharge for 72 crest-stage partial-record stations; and miscellaneous streamflow measurements at 50 stations, and miscellaneous water-quality data recorded by the NAWQA program in Georgia. Volume two of this report contains water resources data for Georgia collected during calendar year 2002, including continuous water-level records of 155 ground-water wells and periodic records at 132 water-quality stations. These data represent that part of the National Water Data System collected by the U.S. Geological Survey and cooperating State and Federal agencies in Georgia.

  4. Water Resources Data, Georgia, 2003, Volume 1: Continuous water-level, streamflow, water-quality data, and periodic water-quality data, Water Year 2003

    USGS Publications Warehouse

    Hickey, Andrew C.; Kerestes, John F.; McCallum, Brian E.

    2004-01-01

    Water resources data for the 2003 water year for Georgia consists of records of stage, discharge, and water quality of streams; and the stage and contents of lakes and reservoirs published in two volumes in a digital format on a CD-ROM. Volume one of this report contains water resources data for Georgia collected during water year 2003, including: discharge records of 163 gaging stations; stage for 187 gaging stations; precipitation for 140 gaging stations; information for 19 lakes and reservoirs; continuous water-quality records for 40 stations; the annual peak stage and annual peak discharge for 65 crest-stage partial-record stations; and miscellaneous streamflow measurements at 36 stations, and miscellaneous water-quality data at 162 stations in Georgia. Volume two of this report contains water resources data for Georgia collected during calendar year 2003, including continuous water-level records of 156 ground-water wells and periodic records at 130 water-quality stations. These data represent that part of the National Water Data System collected by the U.S. Geological Survey and cooperating State and Federal agencies in Georgia.

  5. Use of continuous and grab sample data for calculating total maximum daily load (TMDL) in agricultural watersheds.

    PubMed

    Gulati, Shelly; Stubblefield, Ashley A; Hanlon, Jeremy S; Spier, Chelsea L; Stringfellow, William T

    2014-03-01

    Measuring the discharge of diffuse pollution from agricultural watersheds presents unique challenges. Flows in agricultural watersheds, particularly in Mediterranean climates, can be predominately irrigation runoff and exhibit large diurnal fluctuation in both volume and concentration. Flow and pollutant concentrations in these smaller watersheds dominated by human activity do not conform to a normal distribution and it is not clear if parametric methods are appropriate or accurate for load calculations. The objective of this study was to compare the accuracy of five load estimation methods to calculate pollutant loads from agricultural watersheds. Calculation of loads using results from discrete (grab) samples was compared with the true-load computed using in situ continuous monitoring measurements. A new method is introduced that uses a non-parametric measure of central tendency (the median) to calculate loads (median-load). The median-load method was compared to more commonly used parametric estimation methods which rely on using the mean as a measure of central tendency (mean-load and daily-load), a method that utilizes the total flow volume (volume-load), and a method that uses measure of flow at the time of sampling (instantaneous-load). Using measurements from ten watersheds in the San Joaquin Valley of California, the average percent error compared to the true-load for total dissolved solids (TDS) was 7.3% for the median-load, 6.9% for the mean-load, 6.9% for the volume-load, 16.9% for the instantaneous-load, and 18.7% for the daily-load methods of calculation. The results of this study show that parametric methods are surprisingly accurate, even for data that have starkly non-normal distributions and are highly skewed.

  6. Potential drawbacks associated with agricultural irrigation with treated wastewaters from desalinated water origin and possible remedies.

    PubMed

    Lahav, Ori; Kochva, Malka; Tarchitzky, Jorge

    2010-01-01

    Over 90% of the water supplied in the coastal region in Israel in 2013 (600 Mm(3) y(-1)) will be from desalination plants. The wastewater generated from this water (>400 Mm(3) y(-1)) is planned, after proper treatment, to be reused for agricultural irrigation, making this low-salinity water the main agricultural-sector future water source. In this respect both the Mg(2 + ) concentration and the Sodium Adsorption Ratio value of the water are of concern. We show that the typical Na(+) concentration addition to wastewater (between approximately 100 and approximately 165 mg L(-1)) is much higher than the combined addition of Ca(2 + ) and Mg(2 + ) (between 0 and several mg L(-1)). Since desalinated water is typically supplied with low Ca(2 + ) and Mg(2 + ) concentrations ( approximately 35 and 0 mg L(-1) respectively), the treated wastewater is characterized by very low Mg(2 + ) concentrations, low salinity and very high SAR values, typically >6 and up to 10 (meq L(-1))(0.5). SAR values can be lowered by adding either Ca(2 + ) or Mg(2 + ) to desalinated water. Adding Mg(2 + ) is preferable from both health (minimizing cardiovascular disease hazards) and agriculture (inexpensive Mg fertilization) aspects. The low cost of Mg(2 + ) addition at the post-treatment stage of desalination plants corroborates the request for Mg(2 + ) addition in regions where treated wastewater from desalinated water origin is planned to be reused for irrigation.

  7. Florida Agriculture - Utilizing TRMM to Analyze Sea Breeze Thunderstorm Patterns During El Nino Southern Oscillations and Their Effects Upon Available Fresh Water for South Florida Agricultural Planning and Management

    NASA Technical Reports Server (NTRS)

    Billiot, Amanda; Lee, Lucas; McKee, Jake; Cooley, Zachary Clayton; Mitchell, Brandie

    2010-01-01

    This project utilizes Tropical Rainfall Measuring Mission (TRMM) and Landsat satellite data to assess the impact of sea breeze precipitation upon areas of agricultural land use in southern Florida. Water is a critical resource to agriculture, and the availability of water for agricultural use in Florida continues to remain a key issue. Recent projections of statewide water use by 2020 estimate that 9.3 billion gallons of water per day will be demanded, and agriculture represents 47% of this demand (Bronson 2003). Farmers have fewer options for water supplies than public users and are often limited to using available supplies from surface and ground water sources which depend in part upon variable weather patterns. Sea breeze thunderstorms are responsible for much of the rainfall delivered to Florida during the wet season (May-October) and have been recognized as an important overall contributor of rainfall in southern Florida (Almeida 2003). TRMM satellite data was used to analyze how sea breeze-induced thunderstorms during El Nino and La Nina affected interannual patterns of precipitation in southern Florida from 1998-2009. TRMM's Precipitation Radar and Microwave Imager provide data to quantify water vapor in the atmosphere, precipitation rates and intensity, and the distribution of precipitation. Rainfall accumulation data derived from TRMM and other microwave sensors were used to analyze the temporal and spatial variations of rainfall during each phase of the El Nino Southern Oscillation (ENSO). Through the use of TRMM and Landsat, slight variations were observed, but it was determined that neither sea breeze nor total rainfall patterns in South Florida were strongly affected by ENSO during the study period. However, more research is needed to characterize the influence of ENSO on summer weather patterns in South Florida. This research will provide the basis for continued observations and study with the Global Precipitation Measurement Mission.

  8. Climate change, water, and agriculture: a study of two contrasting regions

    NASA Astrophysics Data System (ADS)

    Kirilenko, A.; Dronin, N.; Zhang, X.

    2009-12-01

    We present a study of potential impacts of climate change on water resources and agriculture in two contrasting regions, the Aral Sea basin in Central Asia and the Northern Great Plains in the United States. The Aral Sea basin is one of the most anthropogenically modified areas of the world; it is also a zone of a water-related ecological crisis. We concentrate on studying water security of five countries in the region, which inherit their water regulation from the planned economy of USSR. Water management was targeted at maximizing agricultural output through diverting the river flow into an extensive and largely ineffective network of irrigation canals. The current water crisis is largely due to human activity; however the region is also strongly impacted by the climate. Climate change will contribute to water problems, escalating irrigation demand during the drought period, and increasing water loss with evaporation. The future of the countries of the Aral Sea basin then depends on both the regional scenario of water management policy and a global scenario of climate change, and is integrated with global socioeconomic scenarios. We formulate a set of regional policy scenarios (“Business as Usual”, “Falling Behind” and “Closing the Gap”) and demonstrate how each of them corresponds to IPCC SRES scenarios, the latter used as an input to the General Circulation Models (GCMs). Then we discuss the relative effectiveness of the introduced scenarios for mitigating water problems in the region, taking into account the adaptation through changing water demand for agriculture. Finally, we introduce the results of multimodel analysis of GCM climate projections, especially in relation to the change in precipitation and frequency of droughts, and discuss the impact of climate change on future development of the region. In the same way as the Aral Sea basin, the Northern Great Plains is expected to be a region heavily impacted by climate change. We concentrate on

  9. 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.

  10. Continuous flushing of contaminants from ballast water tanks.

    PubMed

    Eames, I; Landeryou, M; Greig, A; Snellings, J

    2008-02-01

    The transport of non-indigenous species (NIS) with ship ballast water is a major environmental problem. The International Maritime Organisation (IMO) have recommended that ballast tanks are flushed through with sea water to remove NIS contaminants. The flushing efficiency is studied using mathematical models and a scaled experimental model of a ballast tank. The density contrast between the ballast water and water used for flushing is important when the Froude number Fr(w)=U(w)/sqr rt|g(')|H < 1 (defined in terms of average horizontal flow U(w), reduced buoyancy g', and H the vertical dimension in the tank). When denser water is used to flush a ballast tank, from below, it efficiently displaces lighter ballast water; but flushing through with light water creates a buoyant gravity current which effectively short circuits part of the tank. When Fr(w)>1, the density contrast between the ballast water and water used for flushing is not important and flushing is controlled by a bulk Péclet number, Pe(w). For Pe(w)<1 perfect mixing occurs, while for Pe(w)>1 displacement flushing occurs. Laboratory experiments of flushing were performed using a model two-dimensional ballast tank employing dye attenuation to measure the whole concentration field and these experiments confirm the essential features of the mathematical models. The results of this study are discussed in the context of current IMO flushing protocols. PMID:18086479

  11. Projected water consumption in future global agriculture: scenarios and related impacts.

    PubMed

    Pfister, Stephan; Bayer, Peter; Koehler, Annette; Hellweg, Stefanie

    2011-09-15

    Global stress on water and land resources is increasing as a consequence of population growth and higher caloric food demand. Many terrestrial ecosystems have already massively been degraded for providing agricultural land, and water scarcity related to irrigation has damaged water dependent ecosystems. Coping with the food and biomass demand of an increased population, while minimizing the impacts of crop production, is therefore a massive upcoming challenge. In this context, we developed four strategies to deliver the biotic output for feeding mankind in 2050. Expansion on suitable and intensification of existing areas are compared to assess associated environmental impacts, including irrigation demand, water stress under climate change, and the productivity of the occupied land. Based on the agricultural production pattern and impacts of the strategies we identified the trade-offs between land and water use. Intensification in regions currently under deficit irrigation can increase agricultural output by up to 30%. However, intensified crop production causes enormous water stress in many locations and might not be a viable solution. Furthermore, intensification alone will not be able to meet future food demand: additionally, a reduction of waste by 50% along the food supply chain or expansion of agricultural land is required for satisfying current per-capita meat and bioenergy consumption. Suitable areas for such expansion are mainly located in Africa, followed by South America. The increased land stress is of smaller concern than the water stress modeled for the intensification case. Therefore, a combination of waste reduction with expansion on suitable pastures generally results as the best option, along with some intensification on selected areas. Our results suggested that minimizing environmental impacts requires fundamental changes in agricultural systems and international cooperation, by producing crops where it is most environmentally efficient and not

  12. 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.

  13. Water quality of runoff from agricultural-forestry watersheds in the Geum River Basin, Korea.

    PubMed

    Kim, Geonha; Chung, Sewoong; Lee, Chaeyoung

    2007-11-01

    Forestry and agricultural land uses constitute 85% of Korea and these land uses are typically mixed in many watersheds. Land cover is one of the most important factors affecting diffuse pollution and water quality. The aim of this study is to estimate the pollutant concentrations in runoff from four study watersheds consisting of a mix of forestry and agricultural land uses at different ratios in the Geum River Basin. The effect of topographical variables was also considered. The ratio of agricultural land use to the total area of study watersheds was in the range of 0.01-0.36. Flow rate and water quality (suspended solids, organics and nutrients) of runoff from 40 rainfall events were monitored at the study watersheds. Descriptive statistics showed higher nutrients and organic concentrations in runoff from watershed with higher agricultural activities. Event Mean Concentration (EMC) of individual runoff event was calculated for each water quality constituent based on the flow rate and concentration data of runoff discharge, and arranged on a cumulative probability scale according to runoff occurrence. From the correlation analysis between EMC data and affecting variables, the ratio of agricultural land use to the total area was identified as the parameter that most affected the magnitude of EMC.

  14. Water quality of runoff from agricultural-forestry watersheds in the Geum River Basin, Korea.

    PubMed

    Kim, Geonha; Chung, Sewoong; Lee, Chaeyoung

    2007-11-01

    Forestry and agricultural land uses constitute 85% of Korea and these land uses are typically mixed in many watersheds. Land cover is one of the most important factors affecting diffuse pollution and water quality. The aim of this study is to estimate the pollutant concentrations in runoff from four study watersheds consisting of a mix of forestry and agricultural land uses at different ratios in the Geum River Basin. The effect of topographical variables was also considered. The ratio of agricultural land use to the total area of study watersheds was in the range of 0.01-0.36. Flow rate and water quality (suspended solids, organics and nutrients) of runoff from 40 rainfall events were monitored at the study watersheds. Descriptive statistics showed higher nutrients and organic concentrations in runoff from watershed with higher agricultural activities. Event Mean Concentration (EMC) of individual runoff event was calculated for each water quality constituent based on the flow rate and concentration data of runoff discharge, and arranged on a cumulative probability scale according to runoff occurrence. From the correlation analysis between EMC data and affecting variables, the ratio of agricultural land use to the total area was identified as the parameter that most affected the magnitude of EMC. PMID:17294267

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

    USGS Publications Warehouse

    Anderson, H.W.; 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.

  16. Impact of climate change on the water cycle of agricultural landscapes in Southwest Germany

    NASA Astrophysics Data System (ADS)

    Witte, Irene; Ingwersen, Joachim; Gayler, Sebastian; Streck, Thilo

    2016-04-01

    For agricultural production and life in general, water is a necessity. To ensure food and drinking water security in the future an understanding of the impact of climate change on the water cycle is indispensable. The objective of this PhD research is to assess how higher temperatures, higher atmospheric CO2 concentration and changing precipitation patterns will alter the water cycle of agricultural landscapes in Southwest Germany. As representative key characteristics data evaluation will focus on water use efficiency (WUE) and groundwater recharge. The main research question is whether the positive effect of elevated atmospheric CO2 on WUE will be overcompensated by a decrease in net primary production due to warming and to altered seasonal water availability caused by higher rainfall variability. Elevated atmospheric CO2 stimulates plant growth and improves WUE, whereas higher temperatures are expected to reduce net primary production and groundwater recharge. Another research question referring to groundwater recharge is whether groundwater recharge will increase in winter and decrease in summer in Southwest Germany. Changed groundwater recharge directly affects drinking water supply and is an indicator for possible temporary water shortages in agricultural production. A multi-model ensemble composed of 16 combinations of four crop growth models, two water regime models and two nitrogen models will be calibrated and validated against sets of field data. Field data will be provided by FOR 1965 from 2009-2015 for the Kraichgau region and the Swabian Alb, two contrasting areas with regard to climate and agricultural intensity. By using a multi model ensemble uncertainties in predictions due to different model structures (epistemic uncertainty) can be quantified. The uncertainty related to the randomness of inputs and parameters, the so-called aleatory uncertainty, will be additionally assessed for each of the 16 models. Hence, a more reliable range of future

  17. Modeling future water demand in California from developed and agricultural land uses

    NASA Astrophysics Data System (ADS)

    Wilson, T. S.; Sleeter, B. M.; Cameron, D. R.

    2015-12-01

    Municipal and urban land-use intensification in coming decades will place increasing pressure on water resources in California. The state is currently experiencing one of the most extreme droughts on record. This coupled with earlier spring snowmelt and projected future climate warming will increasingly constrain already limited water supplies. The development of spatially explicit models of future land use driven by empirical, historical land use change data allow exploration of plausible LULC-related water demand futures and potential mitigation strategies. We utilized the Land Use and Carbon Scenario Simulator (LUCAS) state-and-transition simulation model to project spatially explicit (1 km) future developed and agricultural land use from 2012 to 2062 and estimated the associated water use for California's Mediterranean ecoregions. We modeled 100 Monte Carlo simulations to better characterize and project historical land-use change variability. Under current efficiency rates, total water demand was projected to increase 15.1% by 2062, driven primarily by increases in urbanization and shifts to more water intensive crops. Developed land use was projected to increase by 89.8%-97.2% and result in an average 85.9% increase in municipal water use, while agricultural water use was projected to decline by approximately 3.9%, driven by decreases in row crops and increases in woody cropland. In order for water demand in 2062 to balance to current demand levels, the currently mandated 25% reduction in urban water use must remain in place in conjunction with a near 7% reduction in agricultural water use. Scenarios of land-use related water demand are useful for visualizing alternative futures, examining potential management approaches, and enabling better informed resource management decisions.

  18. Future agriculture with minimized phosphorus losses to waters: Research needs and direction.

    PubMed

    Sharpley, Andrew N; Bergström, Lars; Aronsson, Helena; Bechmann, Marianne; Bolster, Carl H; Börling, Katarina; Djodjic, Faruk; Jarvie, Helen P; Schoumans, Oscar F; Stamm, Christian; Tonderski, Karin S; Ulén, Barbro; Uusitalo, Risto; Withers, Paul J A

    2015-03-01

    The series of papers in this issue of AMBIO represent technical presentations made at the 7th International Phosphorus Workshop (IPW7), held in September, 2013 in Uppsala, Sweden. At that meeting, the 150 delegates were involved in round table discussions on major, predetermined themes facing the management of agricultural phosphorus (P) for optimum production goals with minimal water quality impairment. The six themes were (1) P management in a changing world; (2) transport pathways of P from soil to water; (3) monitoring, modeling, and communication; (4) importance of manure and agricultural production systems for P management; (5) identification of appropriate mitigation measures for reduction of P loss; and (6) implementation of mitigation strategies to reduce P loss. This paper details the major challenges and research needs that were identified for each theme and identifies a future roadmap for catchment management that cost-effectively minimizes P loss from agricultural activities.

  19. Estimating the Agricultural Water Consumption of the Yellow River Basin Based on Remote Sensing data

    NASA Astrophysics Data System (ADS)

    Wang, G.

    2015-12-01

    Water shortage for agricultural water use is a major problem in the Yellow River Basin. This research uses NDVI value, meteorological data, supervised classification in remote sensing image classification and actual statistical data to estimate and verify the wheat and maize distribution and their water demand in the Yellow River Basin. The validation of the estimate method is performed by comparing the distribution of CIESIN statistic data for 1990. To obtain the accurate water demand, the study used and compared two methods of calculating the total water demand. The first one is to make the crop water requirement per unit area multiply by estimated crops total area of the basin. The second one is to sum the calculated water demand of each province. The research found that the remote sensing data can be used to estimate the crop area, while it overestimates the water consumption by both of the two methods.

  20. On the Estimation of Evapotranspiration for Future Climate Change Impacts on Agricultural Water Requirements

    NASA Astrophysics Data System (ADS)

    Aloysius, N. R.

    2005-12-01

    Doubling of atmospheric CO2 concentrations are likely to increase the average global temperature by two to five degrees Celsius and would cause significant changes in climate. Changes in temperature will directly impact water requirements of plants. Since agriculture is the major water consumer, accurate estimates of agricultural crop water requirements are required in order for countries to better plan their future water allocations to different sectors, especially to the agriculture sector. Changes in crop water requirements are indicated by changes in reference evapotranspiration (ET). Procedures for estimating ET should be applicable to all climatic conditions and accurate for both short and long term periods, and should not require data or information that is usually of very limited availability. This is of greater importance when it comes to planning regional and country level agricultural water requirements. Three methods to estimate monthly ET, namely Hargreaves method (ETH), Samani method (ETS) and Food and Agricultural Organization's (FAO) modified Penman-Monteith (FAOETP) method are compared with data obtained for the Indian Sub-continent. While ETH and ETS requires minimum data (minimum and maximum temperatures), FAOETP requires the estimation of net solar radiation and wind velocity in addition to the above two and is physically based. The results are compared with Penman-Monteith ET (ETP) computed from field data. Regression analyses were performed considering ETP as dependant variable and the other three ETs' as independent variables. Results indicates that FAOETP has very high correlation with ETP (average monthly R Square = 0.794, CV = 0.157) compared to ETH (average monthly R Square = 0.709, CV=0.163) and ETS (average monthly R Square = 0.458, CV=0.495). While FAOETP method gives better results and has the capability of incorporating more variables to improve its performance, ETH method is also comparable and provides a simplified procedure. Both

  1. Field calibration of surface: a model of agricultural chemicals in surface waters.

    PubMed

    Gustafson, D I

    1990-10-01

    Agricultural chemicals sporadically occur at detectable levels in the surface waters of intensively farmed watersheds. HSPF, a previously released model of agricultural chemicals in surface water, had been used to predict concentrations which were much higher (10 X) than those actually observed during monitoring studies. A new model, SURFACE, is described here which is much simpler than HSPF and gives better predictions of surface water concentrations. SURFACE uses PRZM, an EPA model, to calculate edge-of-field runoff losses and simple hydraulic routing algorithms to determine concentrations at the bottom of large river basins. In water systems sampled during 1985 and 1986, SURFACE predictions of annualized mean concentrations for alachlor, atrazine, cyanazine and metolachlor were within 0.09 ppb half of the time.

  2. Agricultural conversion without external water and nutrient inputs reduces terrestrial vegetation productivity

    USGS Publications Warehouse

    Smith, W. Kolby; Cleveland, Cory C.; Reed, Sasha C.; Running, Steven W.

    2014-01-01

    Driven by global population and standard of living increases, humanity co-opts a growing share of the planet's natural resources resulting in many well-known environmental trade-offs. In this study, we explored the impact of agriculture on a resource fundamental to life on Earth: terrestrial vegetation growth (net primary production; NPP). We demonstrate that agricultural conversion has reduced terrestrial NPP by ~7.0%. Increases in NPP due to agricultural conversion were observed only in areas receiving external inputs (i.e., irrigation and/or fertilization). NPP reductions were found for ~88% of agricultural lands, with the largest reductions observed in areas formerly occupied by tropical forests and savannas (~71% and ~66% reductions, respectively). Without policies that explicitly consider the impact of agricultural conversion on primary production, future demand-driven increases in agricultural output will likely continue to drive net declines in global terrestrial productivity, with potential detrimental consequences for net ecosystem carbon storage and subsequent climate warming.

  3. Concentrating Toxoplasma gondii and Cyclospora cayetanensis from Surface Water and Drinking Water by Continuous Separation Channel Centrifugation

    EPA Science Inventory

    Aims: To evaluate the effectiveness of continuous separation channel centrifugation for concentrating Toxoplasma gondii and Cyclospora cayetanensis from drinking water and environmental waters. Methods and Results: Ready-to-seed vials with known quantities of Toxoplasma gondii a...

  4. Water Resources Data, Georgia, 2001, Volume 1: Continuous water-level, streamflow, water-quality data, and periodic water-quality data, Water Year 2001

    USGS Publications Warehouse

    McCallum, Brian E.; Kerestes, John F.; Hickey, Andrew C.

    2001-01-01

    Water resources data for the 2001 water year for Georgia consists of records of stage, discharge, and water quality of streams; and the stage and contents of lakes and reservoirs published in two volumes in a digital format on a CD-ROM. Volume one of this report contains water resources data for Georgia collected during water year 2001, including: discharge records of 133 gaging stations; stage for 144 gaging stations; precipitation for 58 gaging stations; information for 19 lakes and reservoirs; continuous water-quality records for 17 stations; the annual peak stage and annual peak discharge for 76 crest-stage partial-record stations; and miscellaneous streamflow measurements at 27 stations, and miscellaneous water-quality data recorded by the NAWQA program in Georgia. Volume two of this report contains water resources data for Georgia collected during calendar year 2001, including continuous water-level records of 159 ground-water wells and periodic records at 138 water-quality stations. These data represent that part of the National Water Data System collected by the U.S. Geological Survey and cooperating State and Federal agencies in Georgia. Note: Historically, this report was published as a paper report. For the 1999 and subsequent water-year reports, the Water Resources Data for Georgia changed to a new, more informative and functional format on CD-ROM. The format is based on a geographic information system (GIS) user interface that allows the user to view map locations of the hydrologic monitoring stations and networks within respective river basins.

  5. Development of a Solid Phase Extraction Method for Agricultural Pesticides in Large-Volume Water Samples

    EPA Science Inventory

    An analytical method using solid phase extraction (SPE) and analysis by gas chromatography/mass spectrometry (GC/MS) was developed for the trace determination of a variety of agricultural pesticides and selected transformation products in large-volume high-elevation lake water sa...

  6. LUMINATE: Linking agricultural land use, local water quality and Gulf of Mexico hypoxia

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In this paper, we discuss the importance of developing integrated assessment models to support the design and implementation of policies to address water quality problems associated with agricultural pollution. We describe a new modelling system, LUMINATE, which links land use decisions made at the...

  7. Current developments in soil water sensing for climate, environment, hydrology and agriculture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Knowledge of the four dimensional spatio-temporal status and dynamics of soil water content is becoming indispensable to solutions of agricultural, environmental, climatological and engineering problems at all scales. In agronomy alone, science is severely limited by scant or inaccurate knowledge of...

  8. Effects of agricultural practices and vadose zone stratigraphy on nitrate concentration in ground water in Kansas, USA

    USGS Publications Warehouse

    Townsend, M.A.; Sleezer, R.O.; Macko, S.A.; ,

    1996-01-01

    Differences in nitrate-N concentrations in,around water in Kansas can be explained by variations in agricultural practices and vadose-zone stratigraphy. In northwestern Kansas, past use of a local stream for tailwater runoff from irrigation and high fertilizer applications for sugar-beet farming resulted in high nitrate-N concentrations (12-60 mg L-1; in both soil and ground water. Nitrogen isotope values from the soil and ground water range from +4 to +8? which is typical for a fertilizer source. In parts of south-central Kansas, the use of crop rotation and the presence of both continuous fine-textured layers and a reducing ground-water chemistry resulted in ground-water nitrate-N values of 10 mg L-1; in both soil and grounwater. Nitrogen isotope values of +3 to +7? indicate a fertilizer source. Crop rotation decreased nitrate-N values in the shallow ground water (9 m). However, deeper ground water showed increasing nitrate-N concentrations as a result of past farming practices.

  9. The Continuing Evolution of Water Management in Australia

    NASA Astrophysics Data System (ADS)

    Udall, B.

    2011-12-01

    Since the early 1990s Australia has pursued a broad national agenda of water reform which includes full cost pricing, sufficient water for the environment, water conservation, irrigation infrastructure improvements, and clear delineation of roles and responsibilities of different water institutions among other reforms. A series of substantial changes to commonwealth and state law has resulted from these major initiatives. This reform effort was capped by groundbreaking commonwealth legislation in 2007 and 2008 that to large extent federalized the operation of the nation's largest river system, the Murray-Darling. A new basin wide authority, the MDBA, was created to manage the river via the concept of sustainable diversion limits (SDLs) to be promulgated through additional federal legislation. The October 2010 initial plan for these SDLs suggested cuts in use of up to 40% in the basin and was met with widespread opposition by irrigators. Subsequently, top leadership in the MDBA resigned, a number of parliamentary inquiries were begun, and the entire process has been delayed. How did Australia get to its current position with respect to water reform, and what is the likely outcome of the current delay? How has water management evolved in Australia over the last 20 years? What lessons exist for the Western United States?

  10. Agricultural implications of reduced water supplies in the Green and Upper Yellowstone River Basins

    SciTech Connect

    Lansford, R.R.; Roach, F.; Gollehon, N.R.; Creel, B.J.

    1981-07-01

    The growth of the energy sector in the energy-rich but water-restricted Western US has presented a potential conflict for water now used by the irrigated agricultural sector. This study measures the direct impacts on farm income and employment resulting from the transfer of water from agriculture to energy in two specific geographical areas - the Green and Upper Yellowstone River Basins. We used a linear programming model to evaluate the impacts of reduced water supplies. Through the use of regional multipliers, we expanded our analysis to include regional impacts. In the Green River Basin, we found that Duchesne and Uintah Counties, Utah, would experience the greatest economic impacts when agricultural water supplies were reduced by 50%. In the Upper Yellowstone River Basin, Treasure and Rosebud Counties, Montana, would experience the greatest total income and employment reductions when water supplies were reduced less than or equal to 40%. When these supplies were reduced by more than 40%, Stillwater, Carbon, Yellowstone, and Big Horn Counties, Montana, would experience the greatest reductions.

  11. Can improved agricultural water use efficiency save India’s groundwater?

    NASA Astrophysics Data System (ADS)

    Fishman, Ram; Devineni, Naresh; Raman, Swaminathan

    2015-08-01

    Irrigated agriculture is placing increasing pressure on finite freshwater resources, especially in developing countries, where water extraction is often unregulated, un-priced and even subsidized. To shift agriculture to a more sustainable use of water without harming the food security and livelihoods of hundreds of millions of smallholders, substantial improvements of water use efficiency will be required. Here, we use detailed hydroclimatic and agricultural data to estimate the potential for the widespread adoption of efficient irrigation technologies to halt the depletion of India’s groundwater resources. Even though we find substantial technical potential for reversing water table declines, we show that the impacts are highly sensitive to assumptions about farmers’ water use decisions. For example, we find that widespread adoption of proven technologies that include drip and sprinkler irrigation has the potential to reduce the amount of excessive extraction of groundwater by two thirds. However, under more realistic assumptions about farmers’ irrigation choices, half of these reductions are lost due to the expansion of irrigated area. Our results suggest that without the introduction of incentives for conservation, much of the potential impact of technology adoption on aquifers may be lost. The analysis provides quantitative input to the debate of incentive versus technology based water policies.

  12. 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

  13. Comparative study of irrigation water use and groundwater recharge under various irrigation schemes in an agricultural region, central Taiwan

    NASA Astrophysics Data System (ADS)

    Chen, Shih-Kai; Jang, Cheng-Shin; Tsai, Cheng-Bin

    2016-04-01

    The risk of rice production has increased notably due to climate change in Taiwan. To respond to growing agricultural water shortage without affecting normal food production in the future, the application of water-saving irrigation will be a substantial resolution. However, the adoption of water-saving irrigation may result in the reducing of groundwater recharge because continuous flooding in the paddy fields could be regarded as an important source for groundwater recharge. The aim of this study was to evaluate the irrigation water-saving benefit and groundwater recharge deficit when adopting the System of Rice Intensification, known as SRI methodology, in the Choushui River alluvial fan (the largest groundwater pumping and the most important rice-cropping region in central Taiwan). The three-dimensional finite element groundwater model, FEMWATER, was applied to simulate the infiltration process and groundwater recharge under SRI methodology and traditional irrigation schemes including continuous irrigation, and rotational irrigation in two rice-crop periods with hydro-climatic data of 2013. The irrigation water use was then calculated by water balance. The results showed that groundwater recharge amount of SRI methodology was slightly lower than those of traditional irrigation schemes, reduced 3.6% and 1.6% in the first crop period, and reduced 3.2% and 1.6% in the second crop period, compared with continuous irrigation and rotational irrigation, respectively. However, the SRI methodology achieved notably water-saving benefit compared to the disadvantage of reducing the groundwater recharge amount. The field irrigation requirement amount of SRI methodology was significantly lower than those of traditional irrigation schemes, saving 37% and 20% of irrigation water in the first crop period, and saving 53% and 35% in the second crop period, compared with continuous irrigation and rotational irrigation, respectively. Therefore, the amount of groundwater pumping for

  14. The "Lung": a software-controlled air accumulator for quasi-continuous multi-point measurement of agricultural greenhouse gases

    NASA Astrophysics Data System (ADS)

    Martin, R. J.; Bromley, A. M.; Harvey, M. J.; Moss, R. C.; Pattey, E.; Dow, D.

    2011-10-01

    We describe the design and testing of a flexible bag ("Lung") accumulator attached to a gas chromatographic (GC) analyzer capable of measuring surface-atmosphere greenhouse gas exchange fluxes in a wide range of environmental/agricultural settings. In the design presented here, the Lung can collect up to three gas samples concurrently, each accumulated into a Tedlar bag over a period of 20 min or longer. Toggling collection between 2 sets of 3 bags enables quasi-continuous collection with sequential analysis and discarding of sample residues. The Lung thus provides a flexible "front end" collection system for interfacing to a GC or alternative analyzer and has been used in 2 main types of application. Firstly, it has been applied to micrometeorological assessment of paddock-scale N2O fluxes, discussed here. Secondly, it has been used for the automation of concurrent emission assessment from three sheep housed in metabolic crates with gas tracer addition and sampling multiplexed to a single GC. The Lung allows the same GC equipment used in laboratory discrete sample analysis to be deployed for continuous field measurement. Continuity of measurement enables spatially-averaged N2O fluxes in particular to be determined with greater accuracy, given the highly heterogeneous and episodic nature of N2O emissions. We present a detailed evaluation of the micrometeorological flux estimation alongside an independent tuneable diode laser system, reporting excellent agreement between flux estimates based on downwind vertical concentration differences. Whilst the current design is based around triplet bag sets, the basic design could be scaled up to a larger number of inlets or bags and less frequent analysis (longer accumulation times) where a greater number of sampling points are required.

  15. An inexact risk management model for agricultural land-use planning under water shortage

    NASA Astrophysics Data System (ADS)

    Li, Wei; Feng, Changchun; Dai, Chao; Li, Yongping; Li, Chunhui; Liu, Ming

    2016-09-01

    Water resources availability has a significant impact on agricultural land-use planning, especially in a water shortage area such as North China. The random nature of available water resources and other uncertainties in an agricultural system present risk for land-use planning and may lead to undesirable decisions or potential economic loss. In this study, an inexact risk management model (IRM) was developed for supporting agricultural land-use planning and risk analysis under water shortage. The IRM model was formulated through incorporating a conditional value-at-risk (CVaR) constraint into an inexact two-stage stochastic programming (ITSP) framework, and could be used to control uncertainties expressed as not only probability distributions but also as discrete intervals. The measure of risk about the second-stage penalty cost was incorporated into the model so that the trade-off between system benefit and extreme expected loss could be analyzed. The developed model was applied to a case study in the Zhangweinan River Basin, a typical agricultural region facing serious water shortage in North China. Solutions of the IRM model showed that the obtained first-stage land-use target values could be used to reflect decision-makers' opinions on the long-term development plan. The confidence level α and maximum acceptable risk loss β could be used to reflect decisionmakers' preference towards system benefit and risk control. The results indicated that the IRM model was useful for reflecting the decision-makers' attitudes toward risk aversion and could help seek cost-effective agricultural land-use planning strategies under complex uncertainties.

  16. Contribution of non-agricultural pesticides to pesticide load in surface water.

    PubMed

    Skark, Christian; Zullei-Seibert, Ninette; Willme, Uwe; Gatzemann, Ulrich; Schlett, Claus

    2004-06-01

    Two small creeks, tributaries of the River Ruhr near Schwerte, Federal Republic of Germany, were investigated to reveal the regional agricultural and non-agricultural sources of pesticide inputs and the main pathways to surface water. In addition, the receiving water was monitored for pesticides. The watersheds are situated at the northern margin of the Rhenian Schiefergebirge, a highland landscape in North-Rhine-Westphalia. Solid carboniferous shale is covered by a shallow layer of quaternary unconsolidated rock (porous aquifer thickness <5 m). Occurrence of herbicides such as chlortoluron, isoproturon and terbuthylazine in surface water could be due to their broad agricultural application in regional dominant crops, such as barley, wheat and maize. Occurrence of diuron and glyphosate results from their use in residential settlements and industrial areas as well as from weed control on railway tracks. Atrazine concentrations up to 0.8 microg litre(-1) indicated recent use of this herbicide, which has been banned since 1991, and was also the result of non-agricultural applications. Pathways for pesticide input to the receiving waters were related to both surface run-off and underground passage. Two-thirds of the observed diuron load in the surface water resulted from an input by run-off. This was expected as a result of total herbicide application targets to sealed surfaces infringing current regulations and recommendations. Diuron load varied between 0.6 and 1.2% of the estimated amount applied annually in the investigated catchments. Non-agricultural pesticide use contributed more than two-thirds of the whole observed pesticide load in the tributaries and at least one-third in the River Ruhr.

  17. Accumulation of radium in sediments from continued disposal of produced water and hydraulic fracturing flowback water

    NASA Astrophysics Data System (ADS)

    Warner, N. R.; Menio, E. C.; Landis, J. D.; Vengosh, A.; Lauer, N.; Harkness, J.; Kondash, A.

    2014-12-01

    Recent public interest in high volume slickwater hydraulic fracturing (HVHF) has drawn increased interest in wastewater management practices by the public, researchers, industry, and regulators. The management of wastes, including both fluids and solids, poses many engineering challenges, including elevated total dissolved solids and elevated activities of naturally occurring radioactive materials (NORM). One management option for wastewater in particular, which is used in western Pennsylvania, USA, is treatment at centralized waste treatment facilities [1]. Previous studies conducted from 2010-2012 indicated that one centralized facility, the Josephine Brine Treatment facility, removed the majority of radium from produced water and hydraulic fracturing flowback fluid (HFFF) during treatment, but low activities of radium remained in treated effluent and were discharged to surface water [2]. Despite the treatment process and radium reduction, high activities (200 times higher than upstream/background) accumulated in stream sediments at the point of effluent discharge. Here we present new results from sampling conducted at two additional centralized waste treatment facilities (Franklin Brine Treatment and Hart Brine Treatment facilities) and Josephine Brine Treatment facility conducted in June 2014. Preliminary results indicate radium is released to surface water at very low (<50 pCi/L) to non-detectable activities, however; radium continues to accumulate in sediments surrounding the area of effluent release. Combined, the data indicate that 1) radium continues to be released to surface water streams in western Pennsylvania despite oil and gas operators voluntary ban on treatment and disposal of HFFF in centralized waste treatment facilities, 2) radium accumulation in sediments occurred at multiple brine treatment facilities and is not isolated to a single accidental release of contaminants or a single facility. [1] Wilson, J. M. and J. M. VanBriesen (2012). "Oil and

  18. Sampling trace organic compounds in water: a comparison of a continuous active sampler to continuous passive and discrete sampling methods.

    PubMed

    Coes, Alissa L; Paretti, Nicholas V; Foreman, William T; Iverson, Jana L; Alvarez, David A

    2014-03-01

    A continuous active sampling method was compared to continuous passive and discrete sampling methods for the sampling of trace organic compounds (TOCs) in water. Results from each method are compared and contrasted in order to provide information for future investigators to use while selecting appropriate sampling methods for their research. The continuous low-level aquatic monitoring (CLAM) sampler (C.I.Agent® Storm-Water Solutions) is a submersible, low flow-rate sampler, that continuously draws water through solid-phase extraction media. CLAM samplers were deployed at two wastewater-dominated stream field sites in conjunction with the deployment of polar organic chemical integrative samplers (POCIS) and the collection of discrete (grab) water samples. All samples were analyzed for a suite of 69 TOCs. The CLAM and POCIS samples represent time-integrated samples that accumulate the TOCs present in the water over the deployment period (19-23 h for CLAM and 29 days for POCIS); the discrete samples represent only the TOCs present in the water at the time and place of sampling. Non-metric multi-dimensional scaling and cluster analysis were used to examine patterns in both TOC detections and relative concentrations between the three sampling methods. A greater number of TOCs were detected in the CLAM samples than in corresponding discrete and POCIS samples, but TOC concentrations in the CLAM samples were significantly lower than in the discrete and (or) POCIS samples. Thirteen TOCs of varying polarity were detected by all of the three methods. TOC detections and concentrations obtained by the three sampling methods, however, are dependent on multiple factors. This study found that stream discharge, constituent loading, and compound type all affected TOC concentrations detected by each method. In addition, TOC detections and concentrations were affected by the reporting limits, bias, recovery, and performance of each method.

  19. Sampling trace organic compounds in water: a comparison of a continuous active sampler to continuous passive and discrete sampling methods

    USGS Publications Warehouse

    Coes, Alissa L.; Paretti, Nicholas V.; Foreman, William T.; Iverson, Jana L.; Alvarez, David A.

    2014-01-01

    A continuous active sampling method was compared to continuous passive and discrete sampling methods for the sampling of trace organic compounds (TOCs) in water. Results from each method are compared and contrasted in order to provide information for future investigators to use while selecting appropriate sampling methods for their research. The continuous low-level aquatic monitoring (CLAM) sampler (C.I.Agent® Storm-Water Solutions) is a submersible, low flow-rate sampler, that continuously draws water through solid-phase extraction media. CLAM samplers were deployed at two wastewater-dominated stream field sites in conjunction with the deployment of polar organic chemical integrative samplers (POCIS) and the collection of discrete (grab) water samples. All samples were analyzed for a suite of 69 TOCs. The CLAM and POCIS samples represent time-integrated samples that accumulate the TOCs present in the water over the deployment period (19–23 h for CLAM and 29 days for POCIS); the discrete samples represent only the TOCs present in the water at the time and place of sampling. Non-metric multi-dimensional scaling and cluster analysis were used to examine patterns in both TOC detections and relative concentrations between the three sampling methods. A greater number of TOCs were detected in the CLAM samples than in corresponding discrete and POCIS samples, but TOC concentrations in the CLAM samples were significantly lower than in the discrete and (or) POCIS samples. Thirteen TOCs of varying polarity were detected by all of the three methods. TOC detections and concentrations obtained by the three sampling methods, however, are dependent on multiple factors. This study found that stream discharge, constituent loading, and compound type all affected TOC concentrations detected by each method. In addition, TOC detections and concentrations were affected by the reporting limits, bias, recovery, and performance of each method.

  20. Sampling trace organic compounds in water: a comparison of a continuous active sampler to continuous passive and discrete sampling methods.

    PubMed

    Coes, Alissa L; Paretti, Nicholas V; Foreman, William T; Iverson, Jana L; Alvarez, David A

    2014-03-01

    A continuous active sampling method was compared to continuous passive and discrete sampling methods for the sampling of trace organic compounds (TOCs) in water. Results from each method are compared and contrasted in order to provide information for future investigators to use while selecting appropriate sampling methods for their research. The continuous low-level aquatic monitoring (CLAM) sampler (C.I.Agent® Storm-Water Solutions) is a submersible, low flow-rate sampler, that continuously draws water through solid-phase extraction media. CLAM samplers were deployed at two wastewater-dominated stream field sites in conjunction with the deployment of polar organic chemical integrative samplers (POCIS) and the collection of discrete (grab) water samples. All samples were analyzed for a suite of 69 TOCs. The CLAM and POCIS samples represent time-integrated samples that accumulate the TOCs present in the water over the deployment period (19-23 h for CLAM and 29 days for POCIS); the discrete samples represent only the TOCs present in the water at the time and place of sampling. Non-metric multi-dimensional scaling and cluster analysis were used to examine patterns in both TOC detections and relative concentrations between the three sampling methods. A greater number of TOCs were detected in the CLAM samples than in corresponding discrete and POCIS samples, but TOC concentrations in the CLAM samples were significantly lower than in the discrete and (or) POCIS samples. Thirteen TOCs of varying polarity were detected by all of the three methods. TOC detections and concentrations obtained by the three sampling methods, however, are dependent on multiple factors. This study found that stream discharge, constituent loading, and compound type all affected TOC concentrations detected by each method. In addition, TOC detections and concentrations were affected by the reporting limits, bias, recovery, and performance of each method. PMID:24419241

  1. 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.

  2. Tackling agricultural diffuse pollution: What might uptake of farmer-preferred measures deliver for emissions to water and air?

    PubMed

    Collins, A L; Zhang, Y S; Winter, M; Inman, A; Jones, J I; Johnes, P J; Cleasby, W; Vrain, E; Lovett, A; Noble, L

    2016-03-15

    Mitigation of agricultural diffuse pollution poses a significant policy challenge across Europe and particularly in the UK. Existing combined regulatory and voluntary approaches applied in the UK continue to fail to deliver the necessary environmental outcomes for a variety of reasons including failure to achieve high adoption rates. It is therefore logical to identify specific on-farm mitigation measures towards which farmers express positive attitudes for higher future uptake rates. Accordingly, a farmer attitudinal survey was undertaken during phase one of the Demonstration Test Catchment programme in England to understand those measures towards which surveyed farmers are most receptive to increasing implementation in the future. A total of 29 on-farm measures were shortlisted by this baseline farm survey. This shortlist comprised many low cost or cost-neutral measures suggesting that costs continue to represent a principal selection criterion for many farmers. The 29 measures were mapped onto relevant major farm types and input, assuming 95% uptake, to a national scale multi-pollutant modelling framework to predict the technically feasible impact on annual agricultural emissions to water and air, relative to business as usual. Simulated median emission reductions, relative to current practise, for water management catchments across England and Wales, were estimated to be in the order sediment (20%)>ammonia (16%)>total phosphorus (15%) ≫ nitrate/methane (11%)>nitrous oxide (7%). The corresponding median annual total cost of the modelled scenario to farmers was £3 ha(-1)yr(-1), with a corresponding range of -£84 ha(-1)yr(-1) (i.e. a net saving) to £33 ha(-1)yr(-1). The results suggest that those mitigation measures which surveyed farmers are most inclined to implement in the future would improve the environmental performance of agriculture in England and Wales at minimum to low cost per hectare. PMID:26789365

  3. Tackling agricultural diffuse pollution: What might uptake of farmer-preferred measures deliver for emissions to water and air?

    PubMed

    Collins, A L; Zhang, Y S; Winter, M; Inman, A; Jones, J I; Johnes, P J; Cleasby, W; Vrain, E; Lovett, A; Noble, L

    2016-03-15

    Mitigation of agricultural diffuse pollution poses a significant policy challenge across Europe and particularly in the UK. Existing combined regulatory and voluntary approaches applied in the UK continue to fail to deliver the necessary environmental outcomes for a variety of reasons including failure to achieve high adoption rates. It is therefore logical to identify specific on-farm mitigation measures towards which farmers express positive attitudes for higher future uptake rates. Accordingly, a farmer attitudinal survey was undertaken during phase one of the Demonstration Test Catchment programme in England to understand those measures towards which surveyed farmers are most receptive to increasing implementation in the future. A total of 29 on-farm measures were shortlisted by this baseline farm survey. This shortlist comprised many low cost or cost-neutral measures suggesting that costs continue to represent a principal selection criterion for many farmers. The 29 measures were mapped onto relevant major farm types and input, assuming 95% uptake, to a national scale multi-pollutant modelling framework to predict the technically feasible impact on annual agricultural emissions to water and air, relative to business as usual. Simulated median emission reductions, relative to current practise, for water management catchments across England and Wales, were estimated to be in the order sediment (20%)>ammonia (16%)>total phosphorus (15%) ≫ nitrate/methane (11%)>nitrous oxide (7%). The corresponding median annual total cost of the modelled scenario to farmers was £3 ha(-1)yr(-1), with a corresponding range of -£84 ha(-1)yr(-1) (i.e. a net saving) to £33 ha(-1)yr(-1). The results suggest that those mitigation measures which surveyed farmers are most inclined to implement in the future would improve the environmental performance of agriculture in England and Wales at minimum to low cost per hectare.

  4. Water security: continuous monitoring of water distribution systems for chemical agents by SERS

    NASA Astrophysics Data System (ADS)

    Inscore, Frank; Shende, Chetan; Sengupta, Atanu; Farquharson, Stuart

    2007-04-01

    Ensuring safe water supplies requires continuous monitoring for potential poisons and portable analyzers to map distribution in the event of an attack. In the case of chemical warfare agents (CWAs) analyzers are needed that have sufficient sensitivity (part-per-billion), selectivity (differentiate the CWA from its hydrolysis products), and speed (less than 10 minutes) to be of value. We have been investigating the ability of surface-enhanced Raman spectroscopy (SERS) to meet these requirements by detecting CWAs and their hydrolysis products in water. The expected success of SERS is based on reported detection of single molecules, the one-to-one relationship between a chemical and its Raman spectrum, and the minimal sample preparation requirements. Recently, we have developed a simple sampling device designed to optimize the interaction of the target molecules with the SERS-active material with the goal of increasing sensitivity and decreasing sampling times. This sampling device employs a syringe to draw the water sample containing the analyte into a capillary filled with the SERS-active material. Recently we used such SERS-active capillaries to measure 1 ppb cyanide in water. Here we extend these measurements to nerve agent hydrolysis products using a portable Raman analyzer.

  5. Mercury Cycling in Agricultural and Non-agricultural Wetlands in the Yolo Bypass Wildlife Area, California: Water Column Processes

    NASA Astrophysics Data System (ADS)

    Fleck, J. A.; Alpers, C. N.; Downing, B. D.; Saraceno, J.; Stephenson, M.; Aiken, G. R.; Bergamaschi, B. A.; Stricker, C.

    2007-12-01

    Organic matter (OM) plays a significant role in mercury (Hg) cycling. For instance, aromatic dissolved OM can enhance Hg solubility leading to greater cycling in the water column whereas bioavailable forms of OM may enhance Hg methylation by increasing the microbial activity of Hg-methylating bacteria. Differences in wetland management (e.g. fertilization, plant residue, water depth and movement) can influence the character of OM within the wetland, thus affecting Hg cycling as well. This study is investigating the role of OM in Hg cycling over a wide range of time scales and wetland management practices within the Yolo Bypass Wildlife Area, near Sacramento, California. We are comparing Hg and methylmercury (MeHg) concentrations in the water columns of three agricultural field types (wild rice, white rice, and shallow-flooded fallow) with those in two non-agricultural field types (seasonal and permanent wetlands). The time scales over which variations in Hg and MeHg concentrations are being investigated range from diurnal variations caused by fluctuations in photolytic reactions and microbial activity to seasonal variations caused by plant growth, land management, climate, and fertilization. We relate those concentration fluctuations to the dominant processes affecting OM cycling in the fields. We further evaluate the possible influence of S-bearing fertilizers, such as ammonium sulfate and zinc sulfate, on Hg methylation because of the role that sulfur plays in Hg cycling and Hg-OM interactions. Preliminary results indicate that dissolved OM (DOM) concentrations (operationally defined using a filter with 0.45 ìm pore diameter) increased from 9 milligrams of carbon per liter (mg-C/L) at inflow stations to as high as 30 mg-C/L within the water column of the wetlands. Based on measured optical properties, OM in these wetlands appears to be derived from a mixture of algal activity, plant exudates, and diffusion from the flooded soils, with the proportion of each

  6. Modelling the impacts of agricultural management practices on river water quality in Eastern England.

    PubMed

    Taylor, Sam D; He, Yi; Hiscock, Kevin M

    2016-09-15

    Agricultural diffuse water pollution remains a notable global pressure on water quality, posing risks to aquatic ecosystems, human health and water resources and as a result legislation has been introduced in many parts of the world to protect water bodies. Due to their efficiency and cost-effectiveness, water quality models have been increasingly applied to catchments as Decision Support Tools (DSTs) to identify mitigation options that can be introduced to reduce agricultural diffuse water pollution and improve water quality. In this study, the Soil and Water Assessment Tool (SWAT) was applied to the River Wensum catchment in eastern England with the aim of quantifying the long-term impacts of potential changes to agricultural management practices on river water quality. Calibration and validation were successfully performed at a daily time-step against observations of discharge, nitrate and total phosphorus obtained from high-frequency water quality monitoring within the Blackwater sub-catchment, covering an area of 19.6 km(2). A variety of mitigation options were identified and modelled, both singly and in combination, and their long-term effects on nitrate and total phosphorus losses were quantified together with the 95% uncertainty range of model predictions. Results showed that introducing a red clover cover crop to the crop rotation scheme applied within the catchment reduced nitrate losses by 19.6%. Buffer strips of 2 m and 6 m width represented the most effective options to reduce total phosphorus losses, achieving reductions of 12.2% and 16.9%, respectively. This is one of the first studies to quantify the impacts of agricultural mitigation options on long-term water quality for nitrate and total phosphorus at a daily resolution, in addition to providing an estimate of the uncertainties of those impacts. The results highlighted the need to consider multiple pollutants, the degree of uncertainty associated with model predictions and the risk of

  7. Evaluation of management options for disposal of salt and trace element laden agricultural drainage water from the Fallon Indian Reservation, Fallon, Nevada

    SciTech Connect

    Tokunaga, Tetsu; Benson, S.

    1991-03-01

    This is the final report describing work performed on the Fallon Indian Reservation by the Earth Sciences Division at Lawrence Berkeley Laboratory during FY90. These investigations were initiated at the request of the United States Bureau of Reclamation in response to recent concerns regarding disposal of agriculture drainage water from the Reservation. The Reservation is transected by numerous irrigation and drainage canals, including the TJ Drain. Recent investigations by the US Fish and Wildlife Service have demonstrated that water in the TJ Drain is toxic to several aquatic indicator organisms, including bluegills, fathead minnows and daphnids. This information, coupled with recent die-offs of fish and birds, has lead to concern about continued discharge of TJ Drain water into local surface waters. In late 1990, plans for closing the TJ Drain and providing for alternative drainage were initiated. We aim to provide information for assessing options fro disposal of agricultural drainage water from the Reservation. In particular, our studies focuses on irrigation and drainage of lands currently serviced by the TJ Drain. Options for continued irrigation and drainage of the Reservation fall broadly into two categories: options that provide an alternative to drain water disposal into the SWMA; and options that include continuing the current practice of drain water disposal into the SWMA. Other options include elements of both of these alternatives. Additional discussion of specific options will follow a brief summary of the technical work supporting our assessment of drainage related issues at the Reservation. 67 refs., 57 figs., 15 tabs.

  8. IN-STREAM CONTINUOUS SOURCE WATER QUALITY MONITORING SYSTEM

    EPA Science Inventory

    Abstract:

    The U.S. Environmental Protection Agency (EPA) Office of Research and Development (ORD) provided the Ohio River Valley Water Sanitation Commission (ORSANCO) with a grant as part of the Advanced Measurement Initiative (AMI). The objective of AMI is to provide an ...

  9. 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

  10. Assessment of Agricultural Water Management in Punjab, India using Bayesian Methods

    NASA Astrophysics Data System (ADS)

    Russo, T. A.; Devineni, N.; Lall, U.; Sidhu, R.

    2013-12-01

    The success of the Green Revolution in Punjab, India is threatened by the declining water table (approx. 1 m/yr). Punjab, a major agricultural supplier for the rest of India, supports irrigation with a canal system and groundwater, which is vastly over-exploited. Groundwater development in many districts is greater than 200% the annual recharge rate. The hydrologic data required to complete a mass-balance model are not available for this region, therefore we use Bayesian methods to estimate hydrologic properties and irrigation requirements. Using the known values of precipitation, total canal water delivery, crop yield, and water table elevation, we solve for each unknown parameter (often a coefficient) using a Markov chain Monte Carlo (MCMC) algorithm. Results provide regional estimates of irrigation requirements and groundwater recharge rates under observed climate conditions (1972 to 2002). Model results are used to estimate future water availability and demand to help inform agriculture management decisions under projected climate conditions. We find that changing cropping patterns for the region can maintain food production while balancing groundwater pumping with natural recharge. This computational method can be applied in data-scarce regions across the world, where agricultural water management is required to resolve competition between food security and changing resource availability.

  11. Contamination of soils with microbial pathogens originating from effluent water used for agricultural irrigation

    NASA Astrophysics Data System (ADS)

    Bernstein, N.

    2009-04-01

    The use of wastewater for agricultural irrigation is steadily increasing world-wide and due to shortages of fresh water is common today in most arid regions of the world. The use of treated wastewater for agricultural irrigation may result in soil exposure to pathogens, creating potential public health problems. A variety of human pathogens are present in raw sewage water. Although their concentrations decrease during the wastewater reclamation process, the secondary treated effluents most commonly used for irrigation today still contain bacterial human pathogens. A range of bacterial pathogens, introduced through contaminated irrigation water or manure, are capable of surviving for long periods in soil and water where they have the potential to contaminate crops in the field. Therefore, there is a risk of direct contamination of crops by human pathogens from the treated effluents used for irrigation, as well as a risk of indirect contamination of the crops from contaminated soil at the agricultural site. Contradictory to previous notion, recent studies have demonstrated that human pathogens can enter plants through their roots and translocate and survive in edible, aerial plant tissues. The practical implications of these new findings for food safety are still not clear, but no doubt reflect the pathogenic microorganisms' ability to survive and multiply in the irrigated soil, water, and the harvested edible crop.

  12. 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.

  13. Vegetation Water Content Mapping in a Diverse Agricultural Landscape: National Airborne Field Experiment 2006

    NASA Technical Reports Server (NTRS)

    Cosh, Michael H.; Jing Tao; Jackson, Thomas J.; McKee, Lynn; O'Neill, Peggy

    2011-01-01

    Mapping land cover and vegetation characteristics on a regional scale is critical to soil moisture retrieval using microwave remote sensing. In aircraft-based experiments such as the National Airborne Field Experiment 2006 (NAFE 06), it is challenging to provide accurate high resolution vegetation information, especially on a daily basis. A technique proposed in previous studies was adapted here to the heterogenous conditions encountered in NAFE 06, which included a hydrologically complex landscape consisting of both irrigated and dryland agriculture. Using field vegetation sampling and ground-based reflectance measurements, the knowledge base for relating the Normalized Difference Water Index (NDWI) and the vegetation water content was extended to a greater diversity of agricultural crops, which included dryland and irrigated wheat, alfalfa, and canola. Critical to the generation of vegetation water content maps, the land cover for this region was determined from satellite visible/infrared imagery and ground surveys with an accuracy of 95.5% and a kappa coefficient of 0.95. The vegetation water content was estimated with a root mean square error of 0.33 kg/sq m. The results of this investigation contribute to a more robust database of global vegetation water content observations and demonstrate that the approach can be applied with high accuracy. Keywords: Vegetation, field experimentation, thematic mapper, NDWI, agriculture.

  14. Quality of ground water in agricultural areas of the San Luis Valley, south-central Colorado

    USGS Publications Warehouse

    Edelmann, Patrick; Buckles, D.R.

    1984-01-01

    The quality of ground water in the principal agricultural areas of the San Luis Valley, south-central Colorado was evaluated using chemical analyses of water collected from 57 wells completed in the unconfined aquifer and from 25 wells completed in the confined aquifer. Ground water in both aquifers generally contains dissolved-solids concentrations of less than 500 milligrams per liter. In most areas, calcium is the principal cation in the ground water. Nitrite plus nitrate concentrations expressed as nitrogen, are generally less than 1 milligram per liter. However, the quality of ground water in certain areas may pose health and agricultural hazards. Water in the unconfined aquifer near Center contains high nitrite plus nitrate as nitrogen concentrations. The highest measured concentration in this area was 33 milligrams per liter. Water containing more than 1 milligram per liter of nitrite as nitrogen, or 10 milligrams per liter nitrate, as nitrogen, poses a potential health hazard for infants and should not be used for drinking. In addition, dissolved-solids concentration in the ground water in some areas is greater than 500 milligrams per liter and, if used for irrigation may reduce crop yields. (USGS)

  15. Coupled planning of water resources and agricultural landuse based on an inexact-stochastic programming model

    NASA Astrophysics Data System (ADS)

    Dong, Cong; Huang, Guohe; Tan, Qian; Cai, Yanpeng

    2014-03-01

    Water resources are fundamental for support of regional development. Effective planning can facilitate sustainable management of water resources to balance socioeconomic development and water conservation. In this research, coupled planning of water resources and agricultural land use was undertaken through the development of an inexact-stochastic programming approach. Such an inexact modeling approach was the integration of interval linear programming and chance-constraint programming methods. It was employed to successfully tackle uncertainty in the form of interval numbers and probabilistic distributions existing in water resource systems. Then it was applied to a typical regional water resource system for demonstrating its applicability and validity through generating efficient system solutions. Based on the process of modeling formulation and result analysis, the developed model could be used for helping identify optimal water resource utilization patterns and the corresponding agricultural land-use schemes in three sub-regions. Furthermore, a number of decision alternatives were generated under multiple water-supply conditions, which could help decision makers identify desired management policies.

  16. 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...

  17. Identifying Optimum Landscapes for Water Quality and Ecosystem Services in an Agricultural Watershed

    NASA Astrophysics Data System (ADS)

    Dalzell, B. J.; Pennington, D. N.; Mulla, D.; Polasky, S.; Taff, S.; Nelson, E.

    2011-12-01

    Many areas in the US fail to meet water quality standards. Management actions to improve water quality also impact other ecosystem services, both positively and negatively. We developed an integrated approach to analyze how to meet various levels of water quality while maximizing the net benefits of other ecosystem services in an agricultural watershed. We used the SWAT model (Soil and Water Assessment Tool) to predict crop yield, flow, sediment and phosphorus export and the InVEST (Integrated Valuation of Ecosystem Services and Tradeoffs) model to estimate market returns from agriculture production and non-market values from sediment and phosphorus reduction and from carbon sequestration. We applied these models to an agricultural watershed located in South Central Minnesota to find optimal landscape arrangement for a range of water quality goals. Results showed that the current landscape is near the economic optimum and that market returns from agricultural production dominate total economic returns, even when ecosystem services such as water quality and carbon sequestration are valued. We find that land use patterns that achieve 50% reductions in sediment and phosphorus result in significant annual losses in economic returns (averaging approximately 300/ha and 250/ha for sediment and phosphorus, respectively). When including non-market valuation of ecosystem services, 50% reductions in sediment and phosphorus result in declines in total watershed value an average of about 220/ha and 180/ha for sediment and phosphorus, respectively. However, compared to the current landscape, we show that marginal water quality improvements (10-15% reductions in sediment and phosphorus) could be achieved with no net loss in economic returns. Further, when ecosystem service valuation is included, reductions in sediment and phosphorus on the order of 15-20%, respectively, could be achieved with no net loss of total value. Landscape changes to achieve sediment and phosphorus

  18. Effects of agricultural land-management practices on water quality in northeastern Guilford County, North Carolina, 1985-90

    USGS Publications Warehouse

    Harned, D.A.

    1994-01-01

    The effects of different agricultural land- management practices on sediment, nutrients, and selected pesticides in surface water, and on nutrients and pesticides in ground water were studied in four small basins in the Piedmont of North Carolina. The basins included two adjacent basins in row-crop fields, a mixed land-use basin, and a forested basin. One of the row-crop fields was farmed using conservation land-management practices, including strip cropping, contour plowing, field borders, and grassed waterways. The other field was farmed using standard land- management practices, including continuous cropping, straight-row plowing, and ungrassed waterways. The sediment yield for the standard land-management basin was 2.3 times that for the conservation land-management basin, 14.1 times that for the mixed land-use basin, and 19.5 times that for the forested basin. Nutrient concentra- tions in surface water from the row-crop and mixed land-use basins were higher than those in surface water for the forested basin. Nutrient concentra- tions in soil water and ground water beneath the row-crop basins were lower than those in surface- water runoff for these basins. The lowest nutrient concentrations measured in the row-crop basins generally were in soil-water samples collected just below the root zone (3-foot depth) and in ground water. No significant differences in pesticide concentrations were identified between the surface-water runoff from the standard land- management basin and that from the conservation land-management basin. Concentrations of the soil pesticides isopropalin and flumetralin were higher in the standard land-management basin than in the conservation land-management basin.

  19. 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

  20. The continuous similarity model of bulk soil-water evaporation

    NASA Technical Reports Server (NTRS)

    Clapp, R. B.

    1983-01-01

    The continuous similarity model of evaporation is described. In it, evaporation is conceptualized as a two stage process. For an initially moist soil, evaporation is first climate limited, but later it becomes soil limited. During the latter stage, the evaporation rate is termed evaporability, and mathematically it is inversely proportional to the evaporation deficit. A functional approximation of the moisture distribution within the soil column is also included in the model. The model was tested using data from four experiments conducted near Phoenix, Arizona; and there was excellent agreement between the simulated and observed evaporation. The model also predicted the time of transition to the soil limited stage reasonably well. For one of the experiments, a third stage of evaporation, when vapor diffusion predominates, was observed. The occurrence of this stage was related to the decrease in moisture at the surface of the soil. The continuous similarity model does not account for vapor flow. The results show that climate, through the potential evaporation rate, has a strong influence on the time of transition to the soil limited stage. After this transition, however, bulk evaporation is independent of climate until the effects of vapor flow within the soil predominate.

  1. 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.

  2. 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.

  3. Classification and Mapping of Agricultural Land for National Water-Quality Assessment

    USGS Publications Warehouse

    Gilliom, Robert J.; Thelin, Gail P.

    1997-01-01

    Agricultural land use is one of the most important influences on water quality at national and regional scales. Although there is great diversity in the character of agricultural land, variations follow regional patterns that are influenced by environmental setting and economics. These regional patterns can be characterized by the distribution of crops. A new approach to classifying and mapping agricultural land use for national water-quality assessment was developed by combining information on general land-use distribution with information on crop patterns from agricultural census data. Separate classification systems were developed for row crops and for orchards, vineyards, and nurseries. These two general categories of agricultural land are distinguished from each other in the land-use classification system used in the U.S. Geological Survey national Land Use and Land Cover database. Classification of cropland was based on the areal extent of crops harvested. The acreage of each crop in each county was divided by total row-crop area or total orchard, vineyard, and nursery area, as appropriate, thus normalizing the crop data and making the classification independent of total cropland area. The classification system was developed using simple percentage criteria to define combinations of 1 to 3 crops that account for 50 percent or more or harvested acreage in a county. The classification system consists of 21 level I categories and 46 level II subcategories for row crops, and 26 level I categories and 19 level II subcategories for orchards, vineyards, and nurseries. All counties in the United States with reported harvested acreage are classified in these categories. The distribution of agricultural land within each county, however, must be evaluated on the basis of general land-use data. This can be done at the national scale using 'Major Land Uses of the United States,' at the regional scale using data from the national Land Use and Land Cover database, or at

  4. 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

  5. Cattle, clean water, and climate change: policy choices for the Brazilian Agricultural Frontier.

    PubMed

    Bell, Andrew Reid; Lemos, Maria Carmen; Scavia, Donald

    2010-11-15

    In the Amazonian agricultural frontier, pasture for cattle ranching is an important and potentially hazardous form of land use because of sediment erosion as pastures degrade. This relationship between ranching, sediment load, and water quality is likely to further exacerbate environmental impacts, particularly in the context of climate change. We examine the role that river basin councils (RBCs) - a water governance option of Brazil's 1997 National Water Act - might play in managing this nonpoint-source pollution in the Amazônian state of Rondônia. We implement a simple coupled rancher-water system model to compare two potential governance options: a bulk water cleanup charge (BWC) implemented by RBCs and a land-use fine (LUF) for failing to maintain riparian buffers. We find no significant advantage of BWC over LUF in reducing sediment loading while keeping ranching profitable, under a changing climate. We also fail to find in Rondônia the important stake in water issues that has driven water reform elsewhere in Brazil. Moreover, the comparative success of reforestation programs suggests these programs may, in fact, have the potential to manage nonpoint-source agricultural pollution in the region. PMID:20961050

  6. Comparison of Land, Water, and Energy Requirements of Lettuce Grown Using Hydroponic vs. Conventional Agricultural Methods.

    PubMed

    Barbosa, Guilherme Lages; Gadelha, Francisca Daiane Almeida; Kublik, Natalya; Proctor, Alan; Reichelm, Lucas; Weissinger, Emily; Wohlleb, Gregory M; Halden, Rolf U

    2015-06-16

    The land, water, and energy requirements of hydroponics were compared to those of conventional agriculture by example of lettuce production in Yuma, Arizona, USA. Data were obtained from crop budgets and governmental agricultural statistics, and contrasted with theoretical data for hydroponic lettuce production derived by using engineering equations populated with literature values. Yields of lettuce per greenhouse unit (815 m2) of 41 ± 6.1 kg/m2/y had water and energy demands of 20 ± 3.8 L/kg/y and 90,000 ± 11,000 kJ/kg/y (±standard deviation), respectively. In comparison, conventional production yielded 3.9 ± 0.21 kg/m2/y of produce, with water and energy demands of 250 ± 25 L/kg/y and 1100 ± 75 kJ/kg/y, respectively. Hydroponics offered 11 ± 1.7 times higher yields but required 82 ± 11 times more energy compared to conventionally produced lettuce. To the authors' knowledge, this is the first quantitative comparison of conventional and hydroponic produce production by example of lettuce grown in the southwestern United States. It identified energy availability as a major factor in assessing the sustainability of hydroponics, and it points to water-scarce settings offering an abundance of renewable energy (e.g., from solar, geothermal, or wind power) as particularly attractive regions for hydroponic agriculture.

  7. Comparison of Land, Water, and Energy Requirements of Lettuce Grown Using Hydroponic vs. Conventional Agricultural Methods.

    PubMed

    Barbosa, Guilherme Lages; Gadelha, Francisca Daiane Almeida; Kublik, Natalya; Proctor, Alan; Reichelm, Lucas; Weissinger, Emily; Wohlleb, Gregory M; Halden, Rolf U

    2015-06-01

    The land, water, and energy requirements of hydroponics were compared to those of conventional agriculture by example of lettuce production in Yuma, Arizona, USA. Data were obtained from crop budgets and governmental agricultural statistics, and contrasted with theoretical data for hydroponic lettuce production derived by using engineering equations populated with literature values. Yields of lettuce per greenhouse unit (815 m2) of 41 ± 6.1 kg/m2/y had water and energy demands of 20 ± 3.8 L/kg/y and 90,000 ± 11,000 kJ/kg/y (±standard deviation), respectively. In comparison, conventional production yielded 3.9 ± 0.21 kg/m2/y of produce, with water and energy demands of 250 ± 25 L/kg/y and 1100 ± 75 kJ/kg/y, respectively. Hydroponics offered 11 ± 1.7 times higher yields but required 82 ± 11 times more energy compared to conventionally produced lettuce. To the authors' knowledge, this is the first quantitative comparison of conventional and hydroponic produce production by example of lettuce grown in the southwestern United States. It identified energy availability as a major factor in assessing the sustainability of hydroponics, and it points to water-scarce settings offering an abundance of renewable energy (e.g., from solar, geothermal, or wind power) as particularly attractive regions for hydroponic agriculture. PMID:26086708

  8. Comparison of Land, Water, and Energy Requirements of Lettuce Grown Using Hydroponic vs. Conventional Agricultural Methods

    PubMed Central

    Lages Barbosa, Guilherme; Almeida Gadelha, Francisca Daiane; Kublik, Natalya; Proctor, Alan; Reichelm, Lucas; Weissinger, Emily; Wohlleb, Gregory M.; Halden, Rolf U.

    2015-01-01

    The land, water, and energy requirements of hydroponics were compared to those of conventional agriculture by example of lettuce production in Yuma, Arizona, USA. Data were obtained from crop budgets and governmental agricultural statistics, and contrasted with theoretical data for hydroponic lettuce production derived by using engineering equations populated with literature values. Yields of lettuce per greenhouse unit (815 m2) of 41 ± 6.1 kg/m2/y had water and energy demands of 20 ± 3.8 L/kg/y and 90,000 ± 11,000 kJ/kg/y (±standard deviation), respectively. In comparison, conventional production yielded 3.9 ± 0.21 kg/m2/y of produce, with water and energy demands of 250 ± 25 L/kg/y and 1100 ± 75 kJ/kg/y, respectively. Hydroponics offered 11 ± 1.7 times higher yields but required 82 ± 11 times more energy compared to conventionally produced lettuce. To the authors’ knowledge, this is the first quantitative comparison of conventional and hydroponic produce production by example of lettuce grown in the southwestern United States. It identified energy availability as a major factor in assessing the sustainability of hydroponics, and it points to water-scarce settings offering an abundance of renewable energy (e.g., from solar, geothermal, or wind power) as particularly attractive regions for hydroponic agriculture. PMID:26086708

  9. 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.

  10. [Relationship Between Agricultural Land and Water Quality of Inflow River in Erhai Lake Basin].

    PubMed

    Pang, Yan; Xiang, Song; Chu, Zhao-sheng; Xue, Li-qiang; Ye, Bi-bi

    2015-11-01

    We studied the relationship between agricultural land and water quality of inflow river in Erhai Lake Basin, by means of spatial and statistical analysis, from the perspective of comprehensive agricultural land and the area percentage of different types of agricultural land. The obtained results indicated that inflow water quality showed a significant spatial difference, the inflow TP pollution in the western inflow rivers of Erhai Basin was serious. The major pollution indicators in the northern and southern inflow rivers (except for D3) were organic matter and nitrogen. The area percentage of agricultural land had a significantly indicative effect on the water quality of inflow river. The area percentage of comprehensive agricultural land negatively correlated with permanganate index, NH4(+) -N, TN and TP contents in wet season, the correlation coefficients were - 0.859, - 0.565, - 0.693, - 0.181. It negatively correlated with permanganate index and NH4(+) -N content in dry season, the correlation coefficients were - 0.384, - 0.328. It had positive relationships with and TN, TP content in dry season, the correlation coefficients were 0.221 and 0.146. The area percentage of different types of agricultural land had an obviously indicative effect on the inflow water quality. Farmland positively correlated with TN and TP contents both in wet and dry seasons. The correlation coefficients between farmland and TN, TP were 0.252, 0.581 in rainy season and were 0.149, 0.511 in dry season. It had positive and negative relationships with permanganate index, NH4(+) -N content in wet season and dry season, respectively. The correlation coefficients between farmland and permanganate index, NH4(+) -N were 0.388, 0.053 in rainy season and were -0.137, -0.147 in dry season. Forest land exhibited an opposite performance to that of farmland. The correlation coefficients between forest land and TN, TP, permanganate index, NH4(+) -N were - 0.526, - 0.275, - 0.469, -0.155 in rainy

  11. Invisible water, visible impact: groundwater use and Indian agriculture under climate change

    NASA Astrophysics Data System (ADS)

    Zaveri, Esha; Grogan, Danielle S.; Fisher-Vanden, Karen; Frolking, Steve; Lammers, Richard B.; Wrenn, Douglas H.; Prusevich, Alexander; Nicholas, Robert E.

    2016-08-01

    India is one of the world’s largest food producers, making the sustainability of its agricultural system of global significance. Groundwater irrigation underpins India’s agriculture, currently boosting crop production by enough to feed 170 million people. Groundwater overexploitation has led to drastic declines in groundwater levels, threatening to push this vital resource out of reach for millions of small-scale farmers who are the backbone of India’s food security. Historically, losing access to groundwater has decreased agricultural production and increased poverty. We take a multidisciplinary approach to assess climate change challenges facing India’s agricultural system, and to assess the effectiveness of large-scale water infrastructure projects designed to meet these challenges. We find that even in areas that experience climate change induced precipitation increases, expansion of irrigated agriculture will require increasing amounts of unsustainable groundwater. The large proposed national river linking project has limited capacity to alleviate groundwater stress. Thus, without intervention, poverty and food insecurity in rural India is likely to worsen.

  12. Water governance, agricultural development and community-level resilience to climate change

    NASA Astrophysics Data System (ADS)

    Evans, T.; Cox, M.; McCord, P.; Caylor, K. K.; Washington-Ottombre, C.; Soderberg, K.; Sadri, S.

    2012-12-01

    Climate and other physical drivers of environmental systems are modifying the global availability of water for irrigation. At the same time population growth is placing an increased demand on water resources as local municipalities promote agricultural production as a mechanism to support human welfare and development. Substantial research focuses on agricultural decision-making and practices to assess current and future demand for water based on crop types and irrigation practices. Equally important is the role of environmental governance as expressed through institutions which, in case the case of water systems, are the rules implemented to allocate water resources across different user groups. In water-limited environments, institutions play a critical role in addressing the challenges posed by water demand exceeding water supply. A pressing global concern is whether institutions that evolved over the last several decades are well suited to meet potential future water demands in the context of climate change and increasing rates of water abstraction. A related question is whether social and cultural conditions enable adaptive governance that can modify institutions to different water availability scenarios. In order to assess cross-scale resilience of households and communities reliant on irrigated agriculture to climate change, methodological tools are needed to characterize these issues of "institutional fit" and institutional change. We have developed a framework for characterizing institutional dynamics as a platform for the cross-site analysis of human-water governance. To demonstrate the utility of this framework we present a coding process applying this framework to irrigation schemes in Kenya. We present findings from research on rural agriculturalists in Kenya investigating irrigation practices and institutions designed to allocate water across communities. Initial indications are that current institutional regimes are suitable for current hydrological

  13. A comparison of the spatial distribution of vadose zone water in forested and agricultural floodplains a century after harvest.

    PubMed

    Kellner, Elliott; Hubbart, Jason A

    2016-01-15

    To improve quantitative understanding of the long-term impact of historic forest removal on floodplain vadose zone water regime, a study was implemented in fall 2010, in the Hinkson Creek Watershed, Missouri, USA. Automated, continuously logging capacitance-frequency probes were installed in a grid-like formation (n=6) and at depths of 15, 30, 50, 75, and 100 cm within a historic agricultural field (Ag) and a remnant bottomland hardwood forest (BHF). Data were logged at thirty minute intervals for the duration of the 2011, 2012, and 2013 hydrologic years. Results showed volumetric water content (VWC) to be significantly different between sites (p<0.01) during the study, with site averages of 33.1 and 32.8% at the Ag and BHF sites, respectively. Semi-variogram analyses indicate the presence of strong (<25%) horizontal and vertical spatial correlation of VWC at the Ag site, and a relatively short-range (25 cm) vertical spatial correlation at the BHF, but only indicate horizontal VWC spatial correlation in the top 30 cm of the BHF profile. Likely mechanisms contributing to patterns of observed differences are contrasting rates and depths of plant water use, and the presence of preferential flow paths in the below ground BHF. Results suggest historic forest removal and cultivation of the Ag site lead to an effective homogenization of the upper soil profile, and facilitated the development of strong VWC spatial dependency. Conversely, higher hydraulic conductivity of the more heterogeneous BHF subsurface likely results in a wetting of the deeper profile (75 cm) during climatically wet periods, and thus a more effective processing of hydrologic inputs. Collective results highlight the greater extent and degree to which forest vegetation impacts subsurface hydrology, relative to grassland/agricultural systems, and point to the value of reestablishing floodplain forests for fresh water routing, water quality, and flood mitigation in mixed-land-use watersheds.

  14. A comparison of the spatial distribution of vadose zone water in forested and agricultural floodplains a century after harvest.

    PubMed

    Kellner, Elliott; Hubbart, Jason A

    2016-01-15

    To improve quantitative understanding of the long-term impact of historic forest removal on floodplain vadose zone water regime, a study was implemented in fall 2010, in the Hinkson Creek Watershed, Missouri, USA. Automated, continuously logging capacitance-frequency probes were installed in a grid-like formation (n=6) and at depths of 15, 30, 50, 75, and 100 cm within a historic agricultural field (Ag) and a remnant bottomland hardwood forest (BHF). Data were logged at thirty minute intervals for the duration of the 2011, 2012, and 2013 hydrologic years. Results showed volumetric water content (VWC) to be significantly different between sites (p<0.01) during the study, with site averages of 33.1 and 32.8% at the Ag and BHF sites, respectively. Semi-variogram analyses indicate the presence of strong (<25%) horizontal and vertical spatial correlation of VWC at the Ag site, and a relatively short-range (25 cm) vertical spatial correlation at the BHF, but only indicate horizontal VWC spatial correlation in the top 30 cm of the BHF profile. Likely mechanisms contributing to patterns of observed differences are contrasting rates and depths of plant water use, and the presence of preferential flow paths in the below ground BHF. Results suggest historic forest removal and cultivation of the Ag site lead to an effective homogenization of the upper soil profile, and facilitated the development of strong VWC spatial dependency. Conversely, higher hydraulic conductivity of the more heterogeneous BHF subsurface likely results in a wetting of the deeper profile (75 cm) during climatically wet periods, and thus a more effective processing of hydrologic inputs. Collective results highlight the greater extent and degree to which forest vegetation impacts subsurface hydrology, relative to grassland/agricultural systems, and point to the value of reestablishing floodplain forests for fresh water routing, water quality, and flood mitigation in mixed-land-use watersheds. PMID:26519576

  15. 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.

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

    PubMed

    Mehnert, Edward; Hwang, Hue-Hwa; Johnson, Thomas M; Sanford, Robert A; Beaumont, Will C; Holm, Thomas 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.

  17. Impact of agricultural expansion on water footprint in the Amazon under climate change scenarios.

    PubMed

    Miguel Ayala, Laura; van Eupen, Michiel; Zhang, Guoping; Pérez-Soba, Marta; Martorano, Lucieta G; Lisboa, Leila S; Beltrao, Norma E

    2016-11-01

    Agricultural expansion and intensification are main drivers of land-use change in Brazil. Soybean is the major crop under expansion in the area. Soybean production involves large amounts of water and fertiliser that act as sources of contamination with potentially negative impacts on adjacent water bodies. These impacts might be intensified by projected climate change in tropical areas. A Water Footprint Assessment (WFA) serves as a tool to assess environmental impacts of water and fertiliser use. The aim of this study was to understand potential impacts on environmental sustainability of agricultural intensification close to a protected forest area of the Amazon under climate change. We carried out a WFA to calculate the water footprint (WF) related to soybean production, Glycine max, to understand the sustainability of the WF in the Tapajós river basin, a region in the Brazilian Amazon with large expansion and intensification of soybean. Based on global datasets, environmental hotspots - potentially unsustainable WF areas - were identified and spatially plotted in both baseline scenario (2010) and projection into 2050 through the use of a land-use change scenario that includes climate change effects. Results show green and grey WF values in 2050 increased by 304% and 268%, respectively. More than one-third of the watersheds doubled their grey WF in 2050. Soybean production in 2010 lies within sustainability limits. However, current soybean expansion and intensification trends lead to large impacts in relation to water pollution and water use, affecting protected areas. Areas not impacted in terms of water pollution dropped by 20.6% in 2050 for the whole catchment, while unsustainability increased 8.1%. Management practices such as water consumption regulations to stimulate efficient water use, reduction of crop water use and evapotranspiration, and optimal fertiliser application control could be key factors in achieving sustainability within a river basin.

  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. Impact of agricultural expansion on water footprint in the Amazon under climate change scenarios.

    PubMed

    Miguel Ayala, Laura; van Eupen, Michiel; Zhang, Guoping; Pérez-Soba, Marta; Martorano, Lucieta G; Lisboa, Leila S; Beltrao, Norma E

    2016-11-01

    Agricultural expansion and intensification are main drivers of land-use change in Brazil. Soybean is the major crop under expansion in the area. Soybean production involves large amounts of water and fertiliser that act as sources of contamination with potentially negative impacts on adjacent water bodies. These impacts might be intensified by projected climate change in tropical areas. A Water Footprint Assessment (WFA) serves as a tool to assess environmental impacts of water and fertiliser use. The aim of this study was to understand potential impacts on environmental sustainability of agricultural intensification close to a protected forest area of the Amazon under climate change. We carried out a WFA to calculate the water footprint (WF) related to soybean production, Glycine max, to understand the sustainability of the WF in the Tapajós river basin, a region in the Brazilian Amazon with large expansion and intensification of soybean. Based on global datasets, environmental hotspots - potentially unsustainable WF areas - were identified and spatially plotted in both baseline scenario (2010) and projection into 2050 through the use of a land-use change scenario that includes climate change effects. Results show green and grey WF values in 2050 increased by 304% and 268%, respectively. More than one-third of the watersheds doubled their grey WF in 2050. Soybean production in 2010 lies within sustainability limits. However, current soybean expansion and intensification trends lead to large impacts in relation to water pollution and water use, affecting protected areas. Areas not impacted in terms of water pollution dropped by 20.6% in 2050 for the whole catchment, while unsustainability increased 8.1%. Management practices such as water consumption regulations to stimulate efficient water use, reduction of crop water use and evapotranspiration, and optimal fertiliser application control could be key factors in achieving sustainability within a river basin. PMID

  20. 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

  1. Using Satellite-based Evapotranspiration Estimation to Characterize Agricultural Irrigation Water Use

    NASA Astrophysics Data System (ADS)

    Zheng, B.; Myint, S. W.; Hendrickx, J. M. H.

    2014-12-01

    The satellite-based evapotranspiration (ET) model permits estimation of water consumption across space and time in a systematic way. Developing tools to monitor water availability and water use is critical to meet future water shortage challenges in the American West. This study applied METRIC (Mapping Evapotranspiration at high Resolution and with Internalized Calibration) to 2001 Landsat imagery to estimate ET of various crop types in Phoenix. The total annual ET estimates are correlated well with the actual water use at the irrigation district level (r=0.99). We further incorporated a crop type map to estimate annual ET for the major crop types in the region, and to examine variability in crop water use among different irrigation districts. Our results show that alfalfa and double crops consume more water than other crop types with mean annual ET estimations of 1300 to 1580 mm/year, and that cotton uses more water (1162 mm/year) than corn (838 mm/year) and sorghum (829 mm/year) as expected. Crop water use varies from one irrigation district to another due to differences in soil quality, water quality, and farming practices. Results from our study suggest that the ET maps derived from METRIC can be used to quantify the spatial distribution of ET and to characterize agricultural water use by crop types at different spatial scales.

  2. Modelling tools to support the harmonization of Water Framework Directive and Common Agricultural Policy

    NASA Astrophysics Data System (ADS)

    Tediosi, A.; Bulgheroni, C.; Sali, G.; Facchi, A.; Gandolfi, C.

    2009-04-01

    After a few years from the delivery of the EU Water Framework Directive (WFD) the need to link agriculture and WFD has emerged as one of the highest priorities; therefore, it is important to discuss on how the EU Common Agricultural Policy (CAP) can contribute to the achievements of the WFD objectives. The recent CAP reform - known as Mid Term Review (MTR) or Fischler Reform - has increased the opportunities, offering to farmers increased support to address some environmental issues. The central novelty coming from the MTR is the introduction of a farm single payment which aims to the Decoupling of EU Agricultural Support from production. Other MTR important topics deal with the Modulation of the payments, the Cross-Compliance and the strengthening of the Rural Development policy. All these new elements will affect the farmers' behaviour, steering their productive choices for the future, which, in turn, will have consequences on the water demand for irrigation. Indeed, from the water quantity viewpoint, agriculture is a large consumer and improving water use efficiency is one of the main issues at stake, following the increasing impacts of water scarcity and droughts across Europe in a context of climate change. According to a recent survey of the European Commission the saving potential in the agricultural sector is 43% of present abstraction and 95% of it is concentrated in southern europe. Many models have been developed to forecast the farmers' behaviour as a consequence of agricultural policies, both at sector and regional level; all of them are founded on Mathematical Programming techniques and many of them use the Positive approach, which better fits the territorial dimension. A large body of literature also exists focusing on the assessment of irrigation water requirements. The examples of conjunctive modelling of the two aspects are however much more limited. The work presented has got some innovative aspects: not only does it couple an economical model

  3. 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

  4. Assessing Pesticide Contamination to Fresh Water in Some Agricultural Sites, Close to Oaxaca City, Mexico

    NASA Astrophysics Data System (ADS)

    Tomas, G.

    2002-12-01

    This study presents the results of a survey on pesticides in fresh water in shallow aquifers, rivers and dams in Zaachila, Tlacolula and Etla and agricultural valleys close to Oaxaca City, SW of Mexico. In the study zones, there are generalized uses of pesticides and the impact on the water resources by inadequate use of agricultural activities. Water is used for irrigation and drinking. Surveying criteria was to sample the aquifer (production wells), its water table (dig wells) and a regional water collector (Plan Benito Juarez Yuayapan dam). A total of 14 samples were analyzed for the identification and quantification of organochlorine and organophosphorous pesticides. Method was 508-EPA. Gas chromatographer was a 5890 series II Hewlett Packard, calibrated with several patterns. Results: 10 samples are contaminated with some pesticide of the used patterns; Dieldrin, Chlordano, Malathion, Mirex were not found; Traces of organophosphorus compounds were found in 8 samples, mainly Merphos, Parathion Ethylic and Disulfoton ; There was detected traces of world-forbidden insecticides as Metoxychlor, Parathion Ethylic and Disulfoton; and In one sample (Cuilapam well #1) DDT exceeds, the Mexican maximum limit for potable water (1 mg/l),

  5. Water and energy footprint of irrigated agriculture in the Mediterranean region

    NASA Astrophysics Data System (ADS)

    Daccache, A.; Ciurana, J. S.; Rodriguez Diaz, J. A.; Knox, J. W.

    2014-12-01

    Irrigated agriculture constitutes the largest consumer of freshwater in the Mediterranean region and provides a major source of income and employment for rural livelihoods. However, increasing droughts and water scarcity have highlighted concerns regarding the environmental sustainability of agriculture in the region. An integrated assessment combining a gridded water balance model with a geodatabase and GIS has been developed and used to assess the water demand and energy footprint of irrigated production in the region. Modelled outputs were linked with crop yield and water resources data to estimate water (m3 kg-1) and energy (CO2 kg-1) productivity and identify vulnerable areas or ‘hotspots’. For a selected key crops in the region, irrigation accounts for 61 km3 yr-1 of water abstraction and 1.78 Gt CO2 emissions yr-1, with most emissions from sunflower (73 kg CO2/t) and cotton (60 kg CO2/t) production. Wheat is a major strategic crop in the region and was estimated to have a water productivity of 1000 t Mm-3 and emissions of 31 kg CO2/t. Irrigation modernization would save around 8 km3 of water but would correspondingly increase CO2 emissions by around +135%. Shifting from rain-fed to irrigated production would increase irrigation demand to 166 km3 yr-1 (+137%) whilst CO2 emissions would rise by +270%. The study has major policy implications for understanding the water-energy-food nexus in the region and the trade-offs between strategies to save water, reduce CO2 emissions and/or intensify food production.

  6. Water flowing north of the border: export agriculture and water politics in a rural community in Baja California.

    PubMed

    Zlolniski, Christian

    2011-01-01

    Favored by neoliberal agrarian policies, the production of fresh crops for international markets has become a common strategy for economic development in Mexico and other Latin American countries. But as some scholars have argued, the global fresh produce industry in developing countries in which fresh crops are produced for consumer markets in affluent nations implies “virtual water flows,” the transfer of high volumes of water embedded in these crops across international borders. This article examines the local effects of the production of fresh produce in the San Quintín Valley in northwestern Mexico for markets in the United States. Although export agriculture has fostered economic growth and employment opportunities for indigenous farm laborers, it has also led to the overexploitation of underground finite water resources, and an alarming decline of the quantity and quality of water available for residents’ domestic use. I discuss how neoliberal water policies have further contributed to water inequalities along class and ethnic lines, the hardships settlers endure to secure access to water for their basic needs, and the political protests and social tensions water scarcity has triggered in the region. Although the production of fresh crops for international markets is promoted by organizations such as the World Bank and Inter-American Development Bank as a model for economic development, I argue that it often produces water insecurity for the poorest, threatening the UN goal of ensuring access to clean water as a universal human right.

  7. Agriculture and Water Quality in the Corn Belt: Overview of Issues and Approaches

    Technology Transfer Automated Retrieval System (TEKTRAN)

    More than three decades have elapsed since the passage of the Federal Water Pollution Control Act with its stated goal of zero discharge of pollutants into the nation’s waterways. Yet water quality remains poor in many locations and considerable loading of pollutants continue. This is particularly ...

  8. Study of hybrid power system potential to power agricultural water pump in mountain area

    NASA Astrophysics Data System (ADS)

    Syuhada, Ahmad; Mubarak, Amir Zaki; Maulana, M. Ilham

    2016-03-01

    As industry and Indonesian economy grow fast, there are a lot of agricultural land has changed into housing and industrial land. This causes the agricultural land moves to mountain area. In mountainous agricultural area, farmers use the water resources of small rivers in the groove of the mountain to irrigate the farmland. Farmers use their power to lift up water from the river to their land which causes inefectivity in the work of the farmers. Farmers who have capital utilize pump to raise water to their land. The only way to use pump in mountain area is by using fuel energy as there is no electricity, and the fuel price in mountain area is very expensive. Based on those reasons it is wise to consider the exploration of renewable energy available in the area such as solar energy, wind energy and hybrid energy. This study analyses the potential of the application of hybrid power plant, which is the combination of solar and wind energy, to power agricultural pump. In this research, the data of wind speed and solar radiation are collected from the measurement of BMKG SMPK Plus Sare. Related to the solar energy, the photovoltaic output power calculation is 193 W with duration of irradiation of 5 hours/day. While for the wind energy, the output power of the wind turbine is 459.84 W with blade diameter of 3 m and blow duration of 7 hours/day. The power of the pump is 558 W with 8 hours of usage, and the water capacity is 2.520 liters/hour for farmland with the area of 15 ha. Based on the analysis result, the designed system will generate electricity of 3.210 kW/year with initial investment of US 14,938.

  9. Water and Land Limitations to Future Agricultural Production in the Middle East

    NASA Astrophysics Data System (ADS)

    Koch, J. A. M.; Wimmer, F.; Schaldach, R.

    2015-12-01

    Countries in the Middle East use a large fraction of their scarce water resources to produce cash crops, such as fruit and vegetables, for international markets. At the same time, these countries import large amounts of staple crops, such as cereals, required to meet the nutritional demand of their populations. This makes food security in the Middle East heavily dependent on world market prices for staple crops. Under these preconditions, increasing food demand due to population growth, urban expansion on fertile farmlands, and detrimental effects of a changing climate on the production of agricultural commodities present major challenges to countries in the Middle East that try to improve food security by increasing their self-sufficiency rate of staple crops.We applied the spatio-temporal land-use change model LandSHIFT.JR to simulate how an expansion of urban areas may affect the production of agricultural commodities in Jordan. We furthermore evaluated how climate change and changes in socio-economic conditions may influence crop production. The focus of our analysis was on potential future irrigated and rainfed production (crop yield and area demand) of fruit, vegetables, and cereals. Our simulation results show that the expansion of urban areas and the resulting displacement of agricultural areas does result in a slight decrease in crop yields. This leads to almost no additional irrigation water requirements due to the relocation of agricultural areas, i.e. there is the same amount of "crop per drop". However, taking into account projected changes in socio-economic conditions and climate conditions, a large volume of water would be required for cereal production in order to safeguard current self-sufficiency rates for staple crops. Irrigation water requirements are expected to double until 2025 and to triple until 2050. Irrigated crop yields are projected to decrease by about 25%, whereas there is no decrease in rainfed crop yields to be expected.

  10. Growing water scarcity in agriculture: future challenge to global water security.

    PubMed

    Falkenmark, Malin

    2013-11-13

    As water is an essential component of the planetary life support system, water deficiency constitutes an insecurity that has to be overcome in the process of socio-economic development. The paper analyses the origin and appearance of blue as well as green water scarcity on different scales and with particular focus on risks to food production and water supply for municipalities and industry. It analyses water scarcity originating from both climatic phenomena and water partitioning disturbances on different scales: crop field, country level and the global circulation system. The implications by 2050 of water scarcity in terms of potential country-level water deficits for food self-reliance are analysed, and the compensating dependence on trade in virtual water for almost half the world population is noted. Planetary-scale conditions for sustainability of the global water circulation system are discussed in terms of a recently proposed Planetary Freshwater Boundary, and the consumptive water use reserve left to be shared between water requirements for global food production, fuelwood production and carbon sequestration is discussed. Finally, the importance of a paradigm shift in the further conceptual development of water security is stressed, so that adequate attention is paid to water's fundamental role in both natural and socio-economic systems. PMID:24080619

  11. Growing water scarcity in agriculture: future challenge to global water security.

    PubMed

    Falkenmark, Malin

    2013-11-13

    As water is an essential component of the planetary life support system, water deficiency constitutes an insecurity that has to be overcome in the process of socio-economic development. The paper analyses the origin and appearance of blue as well as green water scarcity on different scales and with particular focus on risks to food production and water supply for municipalities and industry. It analyses water scarcity originating from both climatic phenomena and water partitioning disturbances on different scales: crop field, country level and the global circulation system. The implications by 2050 of water scarcity in terms of potential country-level water deficits for food self-reliance are analysed, and the compensating dependence on trade in virtual water for almost half the world population is noted. Planetary-scale conditions for sustainability of the global water circulation system are discussed in terms of a recently proposed Planetary Freshwater Boundary, and the consumptive water use reserve left to be shared between water requirements for global food production, fuelwood production and carbon sequestration is discussed. Finally, the importance of a paradigm shift in the further conceptual development of water security is stressed, so that adequate attention is paid to water's fundamental role in both natural and socio-economic systems.

  12. Soft Water Level Sensors for Characterizing the Hydrological Behaviour of Agricultural Catchments

    PubMed Central

    Crabit, Armand; Colin, François; Bailly, Jean Stéphane; Ayroles, Hervé; Garnier, François

    2011-01-01

    An innovative soft water level sensor is proposed to characterize the hydrological behaviour of agricultural catchments by measuring rainfall and stream flows. This sensor works as a capacitor coupled with a capacitance to frequency converter and measures water level at an adjustable time step acquisition. It was designed to be handy, minimally invasive and optimized in terms of energy consumption and low-cost fabrication so as to multiply its use on several catchments under natural conditions. It was used as a stage recorder to measure water level dynamics in a channel during a runoff event and as a rain gauge to measure rainfall amount and intensity. Based on the Manning equation, a method allowed estimation of water discharge with a given uncertainty and hence runoff volume at an event or annual scale. The sensor was tested under controlled conditions in the laboratory and under real conditions in the field. Comparisons of the sensor to reference devices (tipping bucket rain gauge, hydrostatic pressure transmitter limnimeter, Venturi channels…) showed accurate results: rainfall intensities and dynamic responses were accurately reproduced and discharges were estimated with an uncertainty usually acceptable in hydrology. Hence, it was used to monitor eleven small agricultural catchments located in the Mediterranean region. Both catchment reactivity and water budget have been calculated. Dynamic response of the catchments has been studied at the event scale through the rising time determination and at the annual scale by calculating the frequency of occurrence of runoff events. It provided significant insight into catchment hydrological behaviour which could be useful for agricultural management perspectives involving pollutant transport, flooding event and global water balance. PMID:22163868

  13. Soft water level sensors for characterizing the hydrological behaviour of agricultural catchments.

    PubMed

    Crabit, Armand; Colin, François; Bailly, Jean Stéphane; Ayroles, Hervé; Garnier, François

    2011-01-01

    An innovative soft water level sensor is proposed to characterize the hydrological behaviour of agricultural catchments by measuring rainfall and stream flows. This sensor works as a capacitor coupled with a capacitance to frequency converter and measures water level at an adjustable time step acquisition. It was designed to be handy, minimally invasive and optimized in terms of energy consumption and low-cost fabrication so as to multiply its use on several catchments under natural conditions. It was used as a stage recorder to measure water level dynamics in a channel during a runoff event and as a rain gauge to measure rainfall amount and intensity. Based on the Manning equation, a method allowed estimation of water discharge with a given uncertainty and hence runoff volume at an event or annual scale. The sensor was tested under controlled conditions in the laboratory and under real conditions in the field. Comparisons of the sensor to reference devices (tipping bucket rain gauge, hydrostatic pressure transmitter limnimeter, Venturi channels…) showed accurate results: rainfall intensities and dynamic responses were accurately reproduced and discharges were estimated with an uncertainty usually acceptable in hydrology. Hence, it was used to monitor eleven small agricultural catchments located in the Mediterranean region. Both catchment reactivity and water budget have been calculated. Dynamic response of the catchments has been studied at the event scale through the rising time determination and at the annual scale by calculating the frequency of occurrence of runoff events. It provided significant insight into catchment hydrological behaviour which could be useful for agricultural management perspectives involving pollutant transport, flooding event and global water balance.

  14. Modeling the infrastructure dynamics of China -- Water, agriculture, energy, and greenhouse gases

    SciTech Connect

    Conrad, S.H.; Drennen, T.E.; Engi, D.; Harris, D.L.; Jeppesen, D.M.; Thomas, R.P.

    1998-08-01

    A comprehensive critical infrastructure analysis of the People`s Republic of China was performed to address questions about China`s ability to meet its long-term grain requirements and energy needs and to estimate greenhouse gas emissions in China likely to result from increased agricultural production and energy use. Four dynamic computer simulation models of China`s infrastructures--water, agriculture, energy and greenhouse gas--were developed to simulate, respectively, the hydrologic budgetary processes, grain production and consumption, energy demand, and greenhouse gas emissions in China through 2025. The four models were integrated into a state-of-the-art comprehensive critical infrastructure model for all of China. This integrated model simulates diverse flows of commodities, such as water and greenhouse gas, between the separate models to capture the overall dynamics of the integrated system. The model was used to generate projections of China`s available water resources and expected water use for 10 river drainage regions representing 100% of China`s mean annual runoff and comprising 37 major river basins. These projections were used to develop estimates of the water surpluses and/or deficits in the three end-use sectors--urban, industrial, and agricultural--through the year 2025. Projections of the all-China demand for the three major grains (corn, wheat, and rice), meat, and other (other grains and fruits and vegetables) were also generated. Each geographic region`s share of the all-China grain demand (allocated on the basis of each region`s share of historic grain production) was calculated in order to assess the land and water resources in each region required to meet that demand. Growth in energy use in six historically significant sectors and growth in greenhouse gas loading were projected for all of China.

  15. Water consumption of agriculture and natural ecosystems at the Amu Darya in Lebap Province, Turkmenistan

    NASA Astrophysics Data System (ADS)

    Thevs, Niels; Ovezmuradov, Kurban

    2013-04-01

    The Amu Darya is the main water source for whole Turkmenistan, but also for the regions Khorezm and Karakalpakistan in Uzbekistan. Due to the arid climate in the Amu Darya river basin, agriculture depends on irrigation with river water being the major source of water. Also the natural ecosystems depend on river water. Until end of the 1970s, the Amu Darya flew into the Aral Sea and, together with the Syr Darya, sustained its water level. From the 1960s until today the area under irrigation has been strongly enlarged. During Soviet Union times, mainly cotton was planted on the newly reclaimed land. After independence, new land was reclaimed, in order to grow wheat. In the course of this land reclamation, the downstream section of the Amu Darya, i.e. in Karakalpakistan faces severe water shortage. Today, the Amu Darya only occasionally reaches the previous shore line of the Aral Sea. Against this background, it is necessary that water consumption along the Amu Darya is limited and water is used efficiently, in order to ensure water supply for downstream water users. The province Lebap in Turkmenistan is located at the middle reaches of the Amu Darya. Thus, it is an example of an administrative unit, which consumes water from the Amu Darya and which should release a sufficient amount of water downstream. Furthermore, Lebap harbours one of the last near-natural riparian forests of Central Asia, i.e. the Amu Darya State Reserve, which also is a water consumer. Therefore, we estimate the water consumption of agriculture (cotton, wheat, rice, and house gardens) and the natural ecosystems within Lebap Province. Water consumption refers to the actual evapo-transpiration. We use Landsat ETM and TM satellite images, in order to produce maps of the actual evapo-transpiration. Afterwards, a land cover map is laid over the ETa maps, in order to retrieve the ETa of the different crops and natural ecosystems. These results are compared with the water norms and quotas given for

  16. Stochastic and recursive calibration for operational, large-scale, agricultural land and water use management models

    NASA Astrophysics Data System (ADS)

    Maneta, M. P.; Kimball, J. S.; Jencso, K. G.

    2015-12-01

    Managing the impact of climatic cycles on agricultural production, on land allocation, and on the state of active and projected water sources is challenging. This is because in addition to the uncertainties associated with climate projections, it is difficult to anticipate how farmers will respond to climatic change or to economic and policy incentives. Some sophisticated decision support systems available to water managers consider farmers' adaptive behavior but they are data intensive and difficult to apply operationally over large regions. Satellite-based observational technologies, in conjunction with models and assimilation methods, create an opportunity for new, cost-effective analysis tools to support policy and decision-making over large spatial extents at seasonal scales.We present an integrated modeling framework that can be driven by satellite remote sensing to enable robust regional assessment and prediction of climatic and policy impacts on agricultural production, water resources, and management decisions. The core of this framework is a widely used model of agricultural production and resource allocation adapted to be used in conjunction with remote sensing inputs to quantify the amount of land and water farmers allocate for each crop they choose to grow on a seasonal basis in response to reduced or enhanced access to water due to climatic or policy restrictions. A recursive Bayesian update method is used to adjust the model parameters by assimilating information on crop acreage, production, and crop evapotranspiration as a proxy for water use that can be estimated from high spatial resolution satellite remote sensing. The data assimilation framework blends new and old information to avoid over-calibration to the specific conditions of a single year and permits the updating of parameters to track gradual changes in the agricultural system.This integrated framework provides an operational means of monitoring and forecasting what crops will be grown

  17. Droughts in the US: Modeling and Forecasting for Agriculture-Water Management and Adaptation

    NASA Astrophysics Data System (ADS)

    Perveen, S.; Devineni, N.; Lall, U.

    2012-12-01

    More than half of all US counties are currently mired in a drought that is considered the worst in decades. A persistent drought can not only lead to widespread impacts on water access with interstate implications (as has been shown in the Southeast US and Texas), chronic scarcity can emerge as a risk in regions where fossil aquifers have become the primary source of supply and are being depleted at rates much faster than recharge (e.g., Midwestern US). The standardized drought indices on which the drought declarations are made in the US so far consider only the static decision frameworks—where only the supply is the control variable and not the water consumption. If a location has low demands, drought as manifest in the usual indices does not really have "proportionate" social impact. Conversely, a modest drought as indicated by the traditional measures may have significant impacts where demand is close to the climatological mean value of precipitation. This may also lead to drought being declared too late or too soon. Against this fact, the importance of improved drought forecasting and preparedness for different sectors of the economy becomes increasingly important. The central issue we propose to address through this paper is the construction and testing of a drought index that considers regional water demands for specific purposes (e.g., crops, municipal use) and their temporal distribution over the year for continental US. Here, we have highlighted the use of the proposed index for three main sectors: (i) water management organizations, (ii) optimizing agricultural water use, and (iii) supply chain water risk. The drought index will consider day-to-day climate variability and sectoral demands to develop aggregate regional conditions or disaggregated indices for water users. For the daily temperature and precipitation data, we are using NLDAS dataset that is available from 1949 onwards. The national agricultural statistics services (NASS) online database has

  18. Management of water for irrigation agriculture in semi-arid areas: Problems and prospects

    NASA Astrophysics Data System (ADS)

    Mvungi, A.; Mashauri, D.; Madulu, N. F.

    Most of the Mwanga district is classified as semi-arid with a rainfall range of 300 and 600 mm. Rainfall patterns in the district are unpredictable and are subject to great fluctuations. Like other semi-arid areas, the district is characterized with land degradation, unreliable rainfall, repeated water shortage, periodic famine, overgrazing, dry land cultivation in the marginal areas and heavy competition for limited biomass between farmers and cattle. Vulnerability here is high due to unreliability of weather. The people of Mwanga are dependent on agriculture for their livelihood. However agriculture is difficult in the area due to inadequate rainfall. For a very long time the people have been dependent on irrigation agriculture to ensure food security. Of late the traditional irrigation system is on the decline threatening food security in the area. This paper examines the state and status of the irrigation canal system in Mwanga district with the view of recommending ways in which it can be improved. The study used participatory, survey and in-depth interviews to obtain both quantitative and qualitative data. The major findings are that social, political, environmental and demographic bases that supported the traditional irrigation system have changed drastically. As a corollary to this, the cultural and religious belief systems that supported and guided the traditional canal system management have been replaced by mistrust and corruption in water allocation. In addition the ownership and management system of the water resources that was vested in the initiator clans has changed and now water user groups own the canals/furrows but they do not own the water sources. This has rendered the control of the water sources difficult if not impossible. Currently the system is faced by a number of problems including shortage of water and poor management as demand for water increases and this has led to serious conflicts among and between crop producers and pastoralists

  19. Nitrogen inputs from agriculture: towards better assessments of eutrophication status in marine waters.

    PubMed

    Andersen, Jesper H; Fossing, Henrik; Hansen, Jens W; Manscher, Ole H; Murray, Ciarán; Petersen, Ditte L J

    2014-11-01

    Nutrient enrichment of coastal marine waters caused by losses of nitrate (NO(3)(-)) from agriculture is an increasing global problem. In the European Union, the Nitrates Directive (ND) of 1991 was meant to be a cornerstone in reducing eutrophication effects in coastal waters downstream from intensively farmed catchments. Although reductions in losses of nitrate have been attained, very few Member States have yet been able to reduce eutrophication effects caused by inputs of NO(3)(-) from agriculture. We report trends in concentrations of NO(3)(-) and chlorophyll-a (Chl-a) in Danish coastal and open marine waters during the period from 1996 to 2011 together with an assessment of eutrophication status based on multiple indicators (e.g. nutrient concentrations, Chl-a, submerged aquatic vegetation and benthic macroinvertebrates). Despite decreasing concentrations of both NO(3)(-)and Chl-a, Danish coastal waters are not yet to be classified as 'unaffected by eutrophication'. In order to improve future pan-European evaluations of the effectiveness of the ND, we argue for the added value of including indicators and assessment principles from other European Directives, i.e. the Water Framework Directive and the Marine Strategy Framework Directive.

  20. Water limited agriculture in Africa: Climate change sensitivity of large scale land investments

    NASA Astrophysics Data System (ADS)

    Rulli, M. C.; D'Odorico, P.; Chiarelli, D. D.; Davis, K. F.

    2015-12-01

    The past few decades have seen unprecedented changes in the global agricultural system with a dramatic increase in the rates of food production fueled by an escalating demand for food calories, as a result of demographic growth, dietary changes, and - more recently - new bioenergy policies. Food prices have become consistently higher and increasingly volatile with dramatic spikes in 2007-08 and 2010-11. The confluence of these factors has heightened demand for land and brought a wave of land investment to the developing world: some of the more affluent countries are trying to secure land rights in areas suitable for agriculture. According to some estimates, to date, roughly 38 million hectares have been acquired worldwide by large scale investors, 16 million of which in Africa. More than 85% of large scale land acquisitions in Africa are by foreign investors. Many land deals are motivated not only by the need for fertile land but for the water resources required for crop production. Despite some recent assessments of the water appropriation associated with large scale land investments, their impact on the water resources of the target countries under present conditions and climate change scenarios remains poorly understood. Here we investigate irrigation water requirements by various crops planted in the acquired land as an indicator of the pressure likely placed by land investors on ("blue") water resources of target regions in Africa and evaluate the sensitivity to climate changes scenarios.

  1. Water Resources Data, Georgia, 2000, Volume 1: Continuous water-level, streamflow, water-quality data, and periodic water-quality data, Water Year 2000

    USGS Publications Warehouse

    McCallum, Brian E.; Hickey, Andrew C.

    2000-01-01

    Water resources data for the 2000 water year for Georgia consists of records of stage, discharge, and water quality of streams; and the stage and contents of lakes and reservoirs published in one volume in a digital format on a CD-ROM. This volume contains discharge records of 125 gaging stations; stage for 20 gaging stations; information for 18 lakes and reservoirs; continuous water-quality records for 10 stations; the annual peak stage and annual peak discharge for 77 crest-stage partial-record stations; and miscellaneous streamflow measurements at 21 stations. These data represent that part of the National Water Data System collected by the U.S. Geological Survey and cooperating State and Federal agencies in Georgia. Note: Historically, this report was published as a paper report. For the 1999 and subsequent water-year reports, the Water Resources Data for Georgia changed to a new, more informative and functional format on CD-ROM. The format is based on a geographic information system (GIS) user interface that allows the user to view map locations of the hydrologic monitoring stations and networks within respective river basins.

  2. An appraisal of policies and institutional frameworks impacting on smallholder agricultural water management in Zimbabwe

    NASA Astrophysics Data System (ADS)

    Nyagumbo, I.; Rurinda, J.

    Policies and institutional frameworks associated with and / or impacting on agricultural water management (AWM) in smallholder farming systems in Zimbabwe were analyzed through literature reviews, feedback from stakeholder workshops, key informant interviews and evaluation of policy impacts on implemented case study projects/programmes. The study showed that Zimbabwe has gone a long way towards developing a water management policy addressing both equity and access, through the Water and ZINWA of 1998. However, lack of incentives for improving efficient management and utilization of water resources once water has reached the farm gate was apparent, apart from punitive economic instruments levied on usage of increased volumes of water. For example, the new water reforms of 1998 penalized water savers through loss of any unused water in their permits to other users. In addition, the ability of smallholder farmers to access water for irrigation or other purposes was influenced by macro and micro-economic policies such as Economic Structural and Adjustment Programme (ESAP), Zimbabwe Programme for Economic and Social Transformation (ZIMPREST), prevailing monetary and fiscal policies, as well as the Land and Agrarian Reform policies. For instance, the implementation of ESAP from 1991 to 95 resulted in a decline in government support to management of communal irrigation schemes, and as a result only gravity-fed schemes survived. Also AWM projects/programmes that were in progress were prematurely terminated. While considerable emphasis was placed on rehabilitation of irrigation infrastructure since the fast track land reform in 1998, the policies remained rather silent on strategies for water management in rainfed systems. The piecemeal nature and fragmentation of policies and institutional frameworks scattered across government ministries and sectors were complex and created difficulties for smallholder farmers to access water resources. Poor policy implementation

  3. 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.

  4. Improving water use in agriculture. Experiences in the Middle East and North Africa

    SciTech Connect

    Tuijl, W.V.

    1993-08-01

    As water becomes more scarce, many countries are under pressure to conserve water, especially in the agricultural sector. This paper examines strategies that save water in river basins, irrigation projects, and on farms throughout the Middle East and North Africa. Countries elsewhere can use these suggestions in their own water conservation strategies. Improved surface irrigation techniques and micro-irrigation systems are evaluated. These systems use sprinkler, drip/trickle, or micro-spray methods. The author reviews the preliminary work that is needed to install modern irrigation technologies. He describes the role that governments must play to improve the infrastructure and institutions that affect water use. He also provides detailed case studies of efficient irrigation practices in Cyprus, Israel, and Jordan. These case studies describe the conditions that made better irrigation technology a necessity. They look at ways to plan for development, management, and utilization of water in the face of growing demand. Key topics include how to oversee water rights, adopt essential land reforms, and install a graduated system of water pricing and allocation. The study also recommends projects in water conservation and research.

  5. Designing bioenergy crop buffers to mitigate nitrous oxide emissions and water quality impacts from agriculture

    NASA Astrophysics Data System (ADS)

    Gopalakrishnan, G.; Negri, C. M.

    2010-12-01

    There is a strong societal need to evaluate and understand the environmental aspects of bioenergy production, especially due to the significant increases in production mandated by many countries, including the United States. Bioenergy is a land-based renewable resource and increases in production are likely to result in large-scale conversion of land from current uses to bioenergy crop production; potentially causing increases in the prices of food, land and agricultural commodities as well as disruption of ecosystems. Current research on the environmental sustainability of bioenergy has largely focused on the potential of bioenergy crops to sequester carbon and mitigate greenhouse gas (GHG) emissions and possible impacts on water quality and quantity. A key assumption in these studies is that bioenergy crops will be grown in a manner similar to current agricultural crops such as corn and hence would affect the environment similarly. This study presents a systems approach where the agricultural, energy and environmental sectors are considered as components of a single system, and bioenergy crops are used to design multi-functional agricultural landscapes that meet society’s requirements for food, energy and environmental protection. We evaluate the production of bioenergy crop buffers on marginal land and using degraded water and discuss the potential for growing cellulosic bioenergy crops such as miscanthus and switchgrass in optimized systems such that (1) marginal land is brought into productive use; (2) impaired water is used to boost yields (3); clean freshwater is left for other uses that require higher water quality; and (4) feedstock diversification is achieved that helps ecological sustainability, biodiversity, and economic opportunities for farmers. The process-based biogeochemical model DNDC was used to simulate crop yield, nitrous oxide production and nitrate concentrations in groundwater when bioenergy crops were grown in buffer strips adjacent to

  6. The challenge of climate change in Spain: Water resources, agriculture and land

    NASA Astrophysics Data System (ADS)

    Vargas-Amelin, Elisa; Pindado, Pablo

    2014-10-01

    Climate change effects are becoming evident worldwide, but some water scarce regions present higher vulnerability. Spain, located in the Mediterranean region, is expected for instance to be highly vulnerable given its unbalanced distribution between water resources availability and existing demands. This article presents an introduction to the main threats of climate change mainly on water resources, but it also assesses effects in interlinked areas such as agriculture, soil and land management. Contents focus on measures and initiatives promoted by the central government and address efforts to establish multi-sectoral coordinating bodies, specific adaptation plans and measures for the different sectors. The article highlights some political aspects, such as the complexity of involved competent authorities in water and land management, the need to strengthen public participation and the conflicts arising from the defence of regional interests. It also makes a link to current EU policies; summarises foreseeable problems derived from climate change effects, and provides some recommendations in the different areas covered.

  7. Towards Using Radar to Detect Water Stress: Observations of an Agricultural Maize Canopy from the SnowScat Scatterometer

    NASA Astrophysics Data System (ADS)

    Steele-Dunne, S. C.; Werner, C. L.; Wiesmann, A.; van Emmerik, T. H. M.; Van De Giesen, N.

    2014-12-01

    Recent field experiments and numerical simulations have demonstrated that leaf water content can vary considerably in response to plant water status and that these variations have a significant impact on backscatter, particularly at higher frequencies (>5GHz). The goal of this study is to characterize the radar backscatter response of vegetation in response to natural variations in moisture availability. This is an essential step to determine if there is role for radar in the detection and monitoring of water stress in vegetation. The SnowScat scatterometer was installed on a tower above a maize canopy in Flevoland in the Netherlands from July to September 2013. Snowscat is a ground-based, fully polarimetric, coherent stepped frequency continuous wave scatterometer operating in the range of 9-18GHz. Since 2009, it has been employed in several field campaigns in Switzerland and Finland to investigate the backscatter characteristics of snow. This study is its first deployment in an agricultural setting. Backscatter was measured hourly at a range of azimuth and elevation angles. Regular destructive vegetation sampling and dielectric property measurements are used to monitor variations in the canopy water content, dielectric properties, and canopy growth. Meteorological data, soil moisture and temperature profiles, canopy air temperature profiles and NDVI data were also collected. Results will be presented to show the influence of canopy growth, hydrometeorological conditions and the canopy moisture content distribution on the radar backscatter as a function of frequency, polarization and elevation angle.

  8. Supplementary calcium ameliorates ammonium toxicity by improving water status in agriculturally important species

    PubMed Central

    Hernández-Gómez, Elvia; Valdez-Aguilar, Luis A.; Cartmill, Donita L.; Cartmill, Andrew D.; Alia-Tajacal, Irán

    2015-01-01

    Fertilization of agricultural plants with ammonium (NH4+) is often desirable because it is less susceptible to leaching than nitrate (NO3−), reducing environmental pollution, risk to human health and economic loss. However, a number of important agricultural species exhibit a reduction in growth when fertilized with NH4+, and increasing the tolerance to NH4+ may be of importance for the establishment of sustainable agricultural systems. The present study explored the feasibility of using calcium (Ca) to increase the tolerance of bell pepper (Capsicum annuum) to NH4+ fertilization. Although NH4+ at proportions ≥25 % of total nitrogen (N) decreased leaf dry mass (DM), supplementary Ca ameliorated this decrease. Increasing NH4+ resulted in decreased root hydraulic conductance (Lo) and root water content (RWC), suggesting that water uptake by roots was impaired. The NH4+-induced reductions in Lo and RWC were mitigated by supplementary Ca. Ammonium induced increased damage to the cell membranes through lipid peroxidation, causing increased electrolyte leakage; Ca did not reduce lipid peroxidation and resulted in increased electrolyte leakage, suggesting that the beneficial effects of Ca on the tolerance to NH4+ may be more of a reflection on its effect on the water status of the plant. Bell pepper plants that received NO3−N had a low concentration of NH4+ in the roots but a high concentration in the leaves, probably due to the high nitrate reductase activity observed. Ammonium nutrition depressed the uptake of potassium, Ca and magnesium, while increasing that of phosphorus. The results obtained in the present study indicate that NH4+ caused growth reduction, nutrient imbalance, membrane integrity impairment, increased activity of antioxidant enzymes and affected water relations. Supplementary Ca partially restored growth of leaves by improving root Lo and water relations, and our results suggest that it may be used as a tool to increase the tolerance to NH4

  9. Supplementary calcium ameliorates ammonium toxicity by improving water status in agriculturally important species.

    PubMed

    Hernández-Gómez, Elvia; Valdez-Aguilar, Luis A; Cartmill, Donita L; Cartmill, Andrew D; Alia-Tajacal, Irán

    2015-01-01

    Fertilization of agricultural plants with ammonium [Formula: see text] is often desirable because it is less susceptible to leaching than nitrate [Formula: see text] reducing environmental pollution, risk to human health and economic loss. However, a number of important agricultural species exhibit a reduction in growth when fertilized with [Formula: see text] and increasing the tolerance to [Formula: see text] may be of importance for the establishment of sustainable agricultural systems. The present study explored the feasibility of using calcium (Ca) to increase the tolerance of bell pepper (Capsicum annuum) to [Formula: see text] fertilization. Although [Formula: see text] at proportions ≥25 % of total nitrogen (N) decreased leaf dry mass (DM), supplementary Ca ameliorated this decrease. Increasing [Formula: see text] resulted in decreased root hydraulic conductance (Lo) and root water content (RWC), suggesting that water uptake by roots was impaired. The [Formula: see text]-induced reductions in Lo and RWC were mitigated by supplementary Ca. Ammonium induced increased damage to the cell membranes through lipid peroxidation, causing increased electrolyte leakage; Ca did not reduce lipid peroxidation and resulted in increased electrolyte leakage, suggesting that the beneficial effects of Ca on the tolerance to [Formula: see text] may be more of a reflection on its effect on the water status of the plant. Bell pepper plants that received [Formula: see text] had a low concentration of [Formula: see text] in the roots but a high concentration in the leaves, probably due to the high nitrate reductase activity observed. Ammonium nutrition depressed the uptake of potassium, Ca and magnesium, while increasing that of phosphorus. The results obtained in the present study indicate that [Formula: see text] caused growth reduction, nutrient imbalance, membrane integrity impairment, increased activity of antioxidant enzymes and affected water relations. Supplementary Ca

  10. Using Coastal Fog to Support Sustainable Water Use in a California Agricultural System

    NASA Astrophysics Data System (ADS)

    Baguskas, S. A.; Loik, M. E.

    2015-12-01

    Impacts of climate change threaten California farmers in a number of ways, most importantly through a decline in freshwater availability, concurrent with a rise in water demand. The future of California's multibillion-dollar agricultural industry depends on increasing water use efficiency on farms. In coastal California, the growing season of economically important crops overlaps with the occurrence of coastal fog, which buffers the summer dry season through shading effects and direct water inputs. While the impacts of coastal fog on plant biology have been extensively studied in natural ecosystems, very few studies have evaluated its direct effects on the water and energy budgets of agricultural systems. The objective of this study was to develop a mechanistic understanding of the relationships between coastal fog and the water and energy budgets of croplands in order to improve estimates of crop-scale evapotranspiration rates, which has potential to curtail groundwater use based on local cloud meteorology. We established three sites on strawberry farms along a coastal-inland gradient in the Salinas Valley, California. At each site, we installed a passive fog collector and a micrometeorological station to monitor variation in microclimate conditions. Flow meters were installed in drip lines to quantify irrigation amount and timing. To assess plant response to foggy and non-foggy conditions, we collected measurements of photosynthesis and transpiration rates at the leaf and canopy-scale between June-September 2015. We found that canopy-level transpiration rates on foggy days were reduced by half compared to sunny, clear days (1.5 and 3 mmol H2O m-2 s-1, respectively). Whereas the amount of direct fog water inputs to the soil did not differ significantly between foggy and clear days, average photosynthetically active radiation between 0900-1100 hr. was reduced from 1500 to 500 μmol photons m-2 s-1 between these sampling periods. Our results provide convincing

  11. Influence of instream habitat and water chemistry on amphibians within channelized agricultural headwater streams

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The widespread use of stream channelization and subsurface tile drainage for draining agricultural fields has led to the development of numerous channelized agricultural headwater streams within agricultural watersheds of the Midwestern United States, Canada, and Europe. Channelized agricultural he...

  12. Modelling the Impact of Land Use Change on Water Quality in Agricultural Catchments

    NASA Astrophysics Data System (ADS)

    Johnes, P. J.; Heathwaite, A. L.

    1997-03-01

    Export coefficient modelling was used to model the impact of agriculture on nitrogen and phosphorus loading on the surface waters of two contrasting agricultural catchments. The model was originally developed for the Windrush catchment where the highly reactive Jurassic limestone aquifer underlying the catchment is well connected to the surface drainage network, allowing the system to be modelled using uniform export coefficients for each nutrient source in the catchment, regardless of proximity to the surface drainage network. In the Slapton catchment, the hydrological pathways are dominated by surface and lateral shallow subsurface flow, requiring modification of the export coefficient model to incorporate a distance-decay component in the export coefficients. The modified model was calibrated against observed total nitrogen and total phosphorus loads delivered to Slapton Ley from inflowing streams in its catchment. Sensitivity analysis was conducted to isolate the key controls on nutrient export in the modified model. The model was validated against long-term records of water quality, and was found to be accurate in its predictions and sensitive to both temporal and spatial changes in agricultural practice in the catchment. The model was then used to forecast the potential reduction in nutrient loading on Slapton Ley associated with a range of catchment management strategies. The best practicable environmental option (BPEO) was found to be spatial redistribution of high nutrient export risk sources to areas of the catchment with the greatest intrinsic nutrient retention capacity.

  13. 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.

  14. Mediterranean agriculture: More efficient irrigation needed to compensate increases in future irrigation water requirements

    NASA Astrophysics Data System (ADS)

    Fader, Marianela; Shi, Sinan; von Bloh, Werner; Bondeau, Alberte; Cramer, Wolfgang

    2016-04-01

    Irrigation in the Mediterranean is of vital importance for food security, employment and economic development. Our research shows that, at present, Mediterranean region could save 35% of water by implementing more efficient irrigation and conveyance systems. Some countries like Syria, Egypt and Turkey have higher saving potentials than others. Currently some crops, especially sugar cane and agricultural trees, consume in average more irrigation water per hectare than annual crops (1). Also under climate change, more efficient irrigation is of vital importance for counteracting increases in irrigation water requirements. The Mediterranean area as a whole might face an increase in gross irrigation requirements between 4% and 18% from climate change alone by the end of the century if irrigation systems and conveyance are not improved. Population growth increases these numbers to 22% and 74%, respectively, affecting mainly the Southern and Eastern Mediterranean. However, improved irrigation technologies and conveyance systems have large water saving potentials, especially in the Eastern Mediterranean, and may be able to compensate to some degree the increases due to climate change and population growth. Both subregions would need around 35% more water than today if they could afford some degree of modernization of irrigation and conveyance systems and benefit from the CO2-fertilization effect (1). However, in some scenarios (in this case as combinations of climate change, irrigation technology, influence of population growth and CO2-fertilization effect) water scarcity may constrain the supply of the irrigation water needed in future in Algeria, Libya, Israel, Jordan, Lebanon, Syria, Serbia, Morocco, Tunisia and Spain (1). In this study, vegetation growth, phenology, agricultural production and irrigation water requirements and withdrawal were simulated with the process-based ecohydrological and agro-ecosystem model LPJmL ("Lund-Potsdam-Jena managed Land") after a

  15. 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

  16. Partitioning of sediment-associated organic matter in agricultural watersheds: controlling parameters and water quality implications

    NASA Astrophysics Data System (ADS)

    Journet, S.; Pellerin, B. A.; Bachand, P. A.; Spencer, R.; Bergamaschi, B. A.; Hernes, P. J.

    2009-12-01

    Sediment-associated organic matter (OM) may constitute a significant source of dissolved organic matter (DOM) in agricultural watersheds, but the partitioning of sediment-bound OM is still poorly characterized in such systems. The Willow Slough agricultural watershed in the Central Valley of California, USA, is the focus of a study of DOM dynamics in agricultural watersheds. Weekly surface water samples collected at the watershed outlet since January 2006 show that dissolved organic carbon (DOC) concentrations increase during summer irrigation up to 7 mg/L, and steadily return to winter baseline concentrations (2 mg/L). A similar trend is observed for total suspended sediment concentrations (TSS), which peak about five weeks earlier than DOC (late June) around 200 mg/L, suggesting that sediments may contribute significantly to the delivery of DOM. We investigated the potential impact of sediment-bound OM partitioning on DOM concentration and composition in agricultural surface waters and will present laboratory data related to the equilibrium abiotic release of DOM from suspended, bed, and bank sediments, collected in the Willow Slough watershed over a range of land uses and hydrologic conditions. Desorption isotherms show distinct DOC contributions between sediment types (from 2 to 15% OC desorbed), with suspended sediment from summer irrigation yielding up to 3.4 times more DOC than winter storm suspended sediment, and 4.8 times more than summer bed sediment. In addition, environmental parameters such as water temperature, conductivity, and pH were found to affect OM partitioning differently, pH displaying the most control on DOC release (up to 60% increase from pH 6.5 to pH 9.5). Finally, a detailed biogeochemical characterization of the desorbed DOM quality (including amino acids composition) will serve as a basis for comparing riverine and sediment-derived DOM. By assessing the contribution of DOM from sediments in agricultural watersheds, this research

  17. Co-creating Understanding in Water Use & Agricultural Resilience in a Multi-scale Natural-human System: Sacramento River Valley--California's Water Heartland in Transition

    NASA Astrophysics Data System (ADS)

    Fairbanks, D. H.; Brimlowe, J.; Chaudry, A.; Gray, K.; Greene, T.; Guzley, R.; Hatfield, C.; Houk, E.; Le Page, C.

    2012-12-01

    The Sacramento River Valley (SRV), valued for its $2.5 billion agricultural production and its biodiversity, is the main supplier of California's water, servicing 25 million people. . Despite rapid changes to the region, little is known about the collective motivations and consequences of land and water use decisions, or the social and environmental vulnerability and resilience of the SRV. The overarching research goal is to examine whether the SRV can continue to supply clean water for California and accommodate agricultural production and biodiversity while coping with climate change and population growth. Without understanding these issues, the resources of the SRV face an uncertain future. The defining goal is to construct a framework that integrates cross-disciplinary and diverse stakeholder perspectives in order to develop a comprehensive understanding of how SRV stakeholders make land and water use decisions. Traditional approaches for modeling have failed to take into consideration multi-scale stakeholder input. Currently there is no effective method to facilitate producers and government agencies in developing a shared representation to address the issues that face the region. To address this gap, researchers and stakeholders are working together to collect and consolidate disconnected knowledge held by stakeholder groups (agencies, irrigation districts, and producers) into a holistic conceptual model of how stakeholders view and make decisions with land and water use under various management systems. Our approach integrates a top-down approach (agency stakeholders) for larger scale management decisions with a conceptual co-creation and data gathering bottom-up approach with local agricultural producer stakeholders for input water and landuse decisions. Land use change models that combine a top-down approach with a bottom-up stakeholder approach are rare and yet essential to understanding how the social process of land use change and ecosystem function are

  18. Agricultural chemicals in Iowa's ground water, 1982-95: What are the trends?

    USGS Publications Warehouse

    Koplin, Dana W.; Hallberg, George; Sneck-Fahrer, D. A.; Libra, Robert

    1997-01-01

    The Iowa Department of Natural Resources. Geological Survey Bureau: the University of Iowa Hygienic Laboratory; and the U.S. Geological Survey (USGS) have been working together to address this question. As part of the Iowa Ground-Water Monitoring Program (IGWM). water samples have been collected from selected Iowa municipal wells since 1982. An examination of this data identified two trends: (1) concentrations of atrazine in Iowa's ground water generally were decreasing over time, and (2) concentrations of metolachlor generally were increasing. Continuing ground-water sampling can determine if these trends represent long-term changes in chemical concentrations.

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

    NASA Astrophysics Data System (ADS)

    Allred, B. J.

    2007-12-01

    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 filter materials have the potential to remove nutrient and pesticide contaminants from agricultural drainage waters before these waters are released from the farm site. Batch tests were conducted to find filter materials potentially capable of removing nutrient (nitrate and phosphate) and pesticide (atrazine) contaminants from subsurface drainage waters. For each batch test, stock solution (40 g) and filter material (5 g) were combined in 50 mL Teflon centrifuge tubes and mixed with a rotator for 24 hours. The stock solution contained 50 mg/L nitrate-N, 0.25 mg/L phosphate-P, 0.4 mg/L atrazine, 570 mg/L calcium sulfate, and 140 mg/L potassium chloride. Calcium sulfate and potassium chloride were added so that the stock solution would contain anions and cations normally found in agricultural drainage waters. There were six replicate batch tests for each filter material. At the completion of each test, solution was removed from the centrifuge tube and analyzed for nitrate-N, phosphate-P, and atrazine. A total of 38 filter materials were tested, which were divided into five classes; high carbon content substances, high iron content substances, high aluminum content substances, surfactant modified clay/zeolite, and coal combustion products. Batch test results generally indicate, that with regard to the five classes of filter materials; high carbon content substances adsorbed atrazine very effectively; high iron content substances worked especially well removing almost all of the phosphate present; high aluminum content substances lowered phosphate levels; surfactant modified clay/zeolite substantially reduced both nitrate and atrazine; and coal combustion products

  20. On-farm bioremediation of dimethazone and trifluralin residues in runoff water from an agricultural field.

    PubMed

    Antonious, George F

    2012-01-01

    Bioremediation is the use of living organisms, primarily microorganisms, to degrade environmental contaminants into less toxic forms. Nine biobeds (ground cavity filled with a mixture of composted organic matter, topsoil, and a surface grass) were established at Kentucky State University research farm (Franklin County, KY) to study the impact of this practice on reducing surface runoff water contamination by residues of dimethazone and trifluralin herbicides arising from an agricultural field. Biobed (biofilter) systems were installed at the bottom of the slope of specially designed runoff plots to examine herbicides retention and degradation before entering streams and rivers. In addition to biobed systems, three soil management practices: municipal sewage sludge (SS), SS mixed with yard waste compost (SS + YW), and no-mulch rototilled bare soil (NM used for comparison purposes) were used to monitor the impact of soil amendments on herbicide residues in soil following natural rainfall events. Organic amendments increased soil organic matter content and herbicide residues retained in soil following rainfall events. Biobeds installed in NM soil reduced dimethazone and trifluralin by 84 and 82%, respectively in runoff water that would have been transported down the land slope of agricultural fields and contaminated natural water resources. Biobeds installed in SS and SS+YW treatments reduced dimethazone by 65 and 46% and trifluralin by 52 and 79%, respectively. These findings indicated that biobeds are effective for treating dimethazone and trifluralin residues in runoff water.

  1. LIBS: a potential tool for industrial/agricultural waste water analysis

    NASA Astrophysics Data System (ADS)

    Karpate, Tanvi; K. M., Muhammed Shameem; Nayak, Rajesh; V. K., Unnikrishnan; Santhosh, C.

    2016-04-01

    Laser Induced Breakdown Spectroscopy (LIBS) is a multi-elemental analysis technique with various advantages and has the ability to detect any element in real time. This technique holds a potential for environmental monitoring and various such analysis has been done in soil, glass, paint, water, plastic etc confirms the robustness of this technique for such applications. Compared to the currently available water quality monitoring methods and techniques, LIBS has several advantages, viz. no need for sample preparation, fast and easy operation, and chemical free during the process. In LIBS, powerful pulsed laser generates plasma which is then analyzed to get quantitative and qualitative details of the elements present in the sample. Another main advantage of LIBS technique is that it can perform in standoff mode for real time analysis. Water samples from industries and agricultural strata tend to have a lot of pollutants making it harmful for consumption. The emphasis of this project is to determine such harmful pollutants present in trace amounts in industrial and agricultural wastewater. When high intensity laser is made incident on the sample, a plasma is generated which gives a multielemental emission spectra. LIBS analysis has shown outstanding success for solids samples. For liquid samples, the analysis is challenging as the liquid sample has the chances of splashing due to the high energy of laser and thus making it difficult to generate plasma. This project also deals with determining the most efficient method for testing of water sample for qualitative as well as quantitative analysis using LIBS.

  2. Can macrophyte harvesting from eutrophic water close the loop on nutrient loss from agricultural land?

    PubMed

    Quilliam, Richard S; van Niekerk, Melanie A; Chadwick, David R; Cross, Paul; Hanley, Nick; Jones, Davey L; Vinten, Andy J A; Willby, Nigel; Oliver, David M

    2015-04-01

    Eutrophication is a major water pollution issue and can lead to excessive growth of aquatic plant biomass (APB). However, the assimilation of nutrients into APB provides a significant target for their recovery and reuse, and harvesting problematic APB in impacted freshwater bodies offers a complementary approach to aquatic restoration, which could potentially deliver multiple wider ecosystem benefits. This critical review provides an assessment of opportunities and risks linked to nutrient recovery from agriculturally impacted water-bodies through the harvesting of APB for recycling and reuse as fertilisers and soil amendments. By evaluating the economic, social, environmental and health-related dimensions of this resource recovery from 'waste' process we propose a research agenda for closing the loop on nutrient transfer from land to water. We identify that environmental benefits are rarely, if ever, prioritised as essential criteria for the exploitation of resources from waste and yet this is key for addressing the current imbalance that sees environmental managers routinely undervaluing the wider environmental benefits that may accrue beyond resource recovery. The approach we advocate for the recycling of 'waste' APB nutrients is to couple the remediation of eutrophic waters with the sustainable production of feed and fertiliser, whilst providing multiple downstream benefits and minimising environmental trade-offs. This integrated 'ecosystem services approach' has the potential to holistically close the loop on agricultural nutrient loss, and thus sustainably recover finite resources such as phosphorus from waste.

  3. Irrigation water quality and the benefits of implementing good agricultural practices during tomato (Lycopersicum esculentum) production.

    PubMed

    Estrada-Acosta, M; Jiménez, M; Chaidez, C; León-Félix, J; Castro-Del Campo, N

    2014-07-01

    The implementation of good agricultural practices (GAP) from irrigation water to the tomato packaging process enhances the safety of fresh produce and its value throughout the food chain. The aim of the present study was to show that fresh produce farms that apply and enforce GAP could reduce the presence of Salmonella in finished produce. Samples were collected biweekly from six packing houses from the central region of Sinaloa, México, for the isolation of Salmonella spp by the ISO 6579:2002 method, and the isolated strains were serotyped and genotyped by the Kauffmman-White scheme and pulsed field gel electrophoresis (PFGE), respectively. Salmonella strains were detected in 13 (36.1 %) irrigation water samples, while only two tomato samples were positive (5.5 %). Eight different serotypes were identified in irrigation water, and Salmonella Oranienburg (34 %) was the most prevalent; however, only Salmonella Agona and Salmonella Weltevreden were present on tomatoes. Salmonella Oranienburg was the most widely dispersed and variable serotype, with 10 different PFGE profiles. Salmonella Weltevreden was isolated from both types of samples, albeit with distinct genetic profiles, implying that the sources of contamination differ. These results confirm the utility of implementing good agricultural practices to reduce Salmonella contamination in irrigation water and the packaging process. PMID:24682661

  4. Can macrophyte harvesting from eutrophic water close the loop on nutrient loss from agricultural land?

    PubMed

    Quilliam, Richard S; van Niekerk, Melanie A; Chadwick, David R; Cross, Paul; Hanley, Nick; Jones, Davey L; Vinten, Andy J A; Willby, Nigel; Oliver, David M

    2015-04-01

    Eutrophication is a major water pollution issue and can lead to excessive growth of aquatic plant biomass (APB). However, the assimilation of nutrients into APB provides a significant target for their recovery and reuse, and harvesting problematic APB in impacted freshwater bodies offers a complementary approach to aquatic restoration, which could potentially deliver multiple wider ecosystem benefits. This critical review provides an assessment of opportunities and risks linked to nutrient recovery from agriculturally impacted water-bodies through the harvesting of APB for recycling and reuse as fertilisers and soil amendments. By evaluating the economic, social, environmental and health-related dimensions of this resource recovery from 'waste' process we propose a research agenda for closing the loop on nutrient transfer from land to water. We identify that environmental benefits are rarely, if ever, prioritised as essential criteria for the exploitation of resources from waste and yet this is key for addressing the current imbalance that sees environmental managers routinely undervaluing the wider environmental benefits that may accrue beyond resource recovery. The approach we advocate for the recycling of 'waste' APB nutrients is to couple the remediation of eutrophic waters with the sustainable production of feed and fertiliser, whilst providing multiple downstream benefits and minimising environmental trade-offs. This integrated 'ecosystem services approach' has the potential to holistically close the loop on agricultural nutrient loss, and thus sustainably recover finite resources such as phosphorus from waste. PMID:25669857

  5. The American Land. Its History, Soil, Water, Wildlife, Agricultural Land Planning, and Land Problems of Today and Tomorrow.

    ERIC Educational Resources Information Center

    Soil Conservation Service (USDA), Washington, DC.

    Presented in this booklet is the commentary for "The American Land," a television series prepared by the Soil Conservation Service and the Graduate School, United States Department of Agriculture, in cooperation with WETA - TV, Washington, D.C. It explores the resource of land in America, its history, soil, water, wildlife, agricultural land…

  6. 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...

  7. Differences in Fish, Amphibian, and Reptile Communities Within Wetlands Created by an Agricultural Water Recycling System in Northwestern Ohio

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Establishment of a 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 store subirriga...

  8. 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

  9. Optimization of integrated water quality management for agricultural efficiency and environmental conservation.

    PubMed

    Fleifle, Amr; Saavedra, Oliver; Yoshimura, Chihiro; Elzeir, Mohamed; Tawfik, Ahmed

    2014-01-01

    The scarcity of water resources in Egypt has necessitated the use of various types of lower quality water. Agricultural drainage water is considered a strategic reserve for meeting increasing freshwater demands. In this study, a novel model series was applied to a drainage basin in the Nile Delta to optimize integrated water quality management for agriculture and the aquatic environment. The proposed model series includes a waste load allocation model, an export coefficient model, a stream water quality model, and a genetic algorithm. This model series offers an optimized solution for determining the required removal levels of total suspended solids (TSS), the chemical oxygen demand (COD) at point and non-point pollution sources, and the source flows that require treatment to meet a given water quality target. The model series was applied during the summer and winter to the El-Qalaa basin in the western delta of the Nile River. Increased pollutant removal and treated fractions at point and non-point sources reduced violations of the TSS standards from 732.6 to 238.9 mg/L in summer and from 543.1 to 380.9 mg/L in winter. Likewise, violations of the COD standards decreased from 112.4 mg/L to 0 (no violations) in summer and from 91.7 mg/L to no violations in winter. Thus, this model is recommended as a decision support tool for determining a desirable waste load allocation solution from a trade-off curve considering costs and the degree of compliance with water quality standards.

  10. Continuous, high-resolution spatial mapping of water isotopes in oceanic environment using a CRDS analyzer combined with a continuous water sampler.

    NASA Astrophysics Data System (ADS)

    Kim-Hak, David; Huang, Kuan; Winkler, Renato

    2016-04-01

    The recent advancements of the laser-based technology -in particular Cavity Ring Down Spectroscopy, CRDS- gave birth to a new generation of water stable isotope analyzers that are user-friendly, compact and field deployable providing in-situ measurements. Furthermore, with last year's launch of the Continuous Water Sampler front-end, CWS, the analyzer system added two additional dimensions to liquid water measurements: real-time and continuous. These features enable the user to construct high resolution water isotope data sets through time and space. Campaigns on the Sacramento-San Joaquin River Delta with the US Geological Survey where the CWS-CRDS system was deployed onto a boat to spatially map sections of the delta, validated the CWS performance and demonstrated its durability on brackish water. The next step for the CWS is to explore oceanic applications with seawater. Early in-house laboratory experiments showed stable performance with brine waters (3% concentration). For the field experiment, we have collaborated with the China State Oceanic Administration to deploy the CWS-CRDS in oceanic environments on cruises along the costal China and Antarctic. Here, we present the results of the analysis collected onboard and compared them with discrete sampling measurements. The long-term test has also allowed us to assess the durability and expected lifetime of the CWS membrane and to recommend the proper maintenance procedure for optimum performance under oceanic conditions.

  11. Workshop 7 (synthesis): trade-offs in water for food and environmental security--urban/agricultural trade-off.

    PubMed

    Rahman, Ausaf-ur; Kadi, Mohammad Ait; Rockström, Johan

    2002-01-01

    Severe stresses are being generated by increasing demand for competing water uses, above all between agriculture and urban needs. Amongst potential solutions considered, two dominated the workshop: virtual water and water reuse. Virtual water implies indirect water use: water-poor countries importing food rather than attempting self-sufficiency and thereby keeping their real water resources for economically more beneficial uses. There are serious political and economic risks associated; one proposed solution is an international virtual water trading council. Improved forms of water reuse, particularly use of treated urban wastewater for irrigation, can maximise the use made of limited supply.

  12. Radon exchange dynamics in a karst system investigated by radon continuous measurements in water: first results.

    PubMed

    Peano, G; Vigna, B; Villavecchia, E; Agnesod, G

    2011-05-01

    In 2008 the underground Karst Laboratory of Bossea Cave started research on radon exchange dynamics between bedrock, cave waters (main collector and percolations) and indoor underground atmosphere. Radon air concentrations, normally high, increase more and more during the collector's floods. An explanation of this is a radon-water solubilisation process more effective in flood events, because of a greater rock-water contact surface. Radon is then carried by water into the cave and released into the air. To verify this, continuous measurements of radon concentration are needed not only in the air, but also in the waters of the cave. So a new device for continuous radon monitoring in water was tested, connected to the AlphaGuard radon monitor. For the first 6 months of 2010, for different sections of the cave, the correlations between radon in the air, radon in the waters and the collector's stream flow fluctuations were presented and discussed. PMID:21586541

  13. Book review: Darwinian agriculture: How understanding evolution can improve agriculture by R. Ford Dennison

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agricultural research continually seeks to increase productivity while protecting soil, water and genetic resources. The book Darwinian Agriculture: How Understanding Evolution Can Improve Agriculture, by R. Ford Dennison, delivers a thought-provoking view of how principles of ecology and evolution ...

  14. Spatio-temporal patterns of soil water storage under dryland agriculture at the watershed scale

    NASA Astrophysics Data System (ADS)

    Ibrahim, Hesham M.; Huggins, David R.

    2011-07-01

    SummarySpatio-temporal patterns of soil water are major determinants of crop yield potential in dryland agriculture and can serve as the basis for delineating precision management zones. Soil water patterns can vary significantly due to differences in seasonal precipitation, soil properties and topographic features. In this study we used empirical orthogonal function (EOF) analysis to characterize the spatial variability of soil water at the Washington State University Cook Agronomy Farm (CAF) near Pullman, WA. During the period 1999-2006, the CAF was divided into three roughly equal blocks (A, B, and C), and soil water at 0.3 m intervals to a depth of 1.5 m measured gravimetrically at approximately one third of the 369 geo-referenced points on the 37-ha watershed. These data were combined with terrain attributes, soil bulk density and apparent soil conductivity (EC a). The first EOF generated from the three blocks explained 73-76% of the soil water variability. Field patterns of soil water based on EOF interpolation varied between wet and dry conditions during spring and fall seasons. Under wet conditions, elevation and wetness index were the dominant factors regulating the spatial patterns of soil water. As soil dries out during summer and fall, soil properties (EC a and bulk density) become more important in explaining the spatial patterns of soil water. The EOFs generated from block B, which represents average topographic and soil properties, provided better estimates of soil water over the entire watershed with larger Nash-Sutcliffe Coefficient of Efficiency (NSCE) values, especially when the first two EOFs were retained. Including more than the first two EOFs did not significantly increase the NSCE of soil water estimate. The EOF interpolation method to estimate soil water variability worked slightly better during spring than during fall, with average NSCE values of 0.23 and 0.20, respectively. The predictable patterns of stored soil water in the spring could

  15. Identification of Entamoeba moshkovskii in Treated Waste Water Used for Agriculture.

    PubMed

    Fonseca, Jairo Andres; Heredia, Rubén Darío; Ortiz, Carolina; Mazo, Martín; Clavijo-Ramírez, Carlos Arturo; Lopez, Myriam Consuelo

    2016-03-01

    We conducted an observational study to determine the prevalence of Entamoeba spp., in samples collected in a waste water treatment plant that provides water for agricultural irrigation. Samples were collected weekly over a period of 10 weeks at representative contamination stages from within the treatment plant. Protozoan identification was performed via light microscopy and culture. PCR amplification of small subunit rRNA gene sequences of E. histolytica/dispar/moshkovskii was performed in culture positive samples. Light microscopy revealed the presence of Entamoeba spp., in 70% (14/20) of the raw waste water samples and in 80% (8/10) of the treated water samples. PCR amplification after culture at both 24 and 37°C revealed that 100% (29/29) of the raw waste water samples and 78.6% (11/14) of the treated waste water were positive for E. moshkovskii. We report the first isolation of E. moshkovskii in Colombia, confirmed by PCR. Recent reports of E. moshkovskii pathogenic potential suggest this finding could constitute a public health risk for people exposed to this water.

  16. Desert agricultural terrace systems at EBA Jawa (Jordan) - Layout, water availability and efficiency

    NASA Astrophysics Data System (ADS)

    Meister, Julia; Krause, Jan; Müller-Neuhof, Bernd; Portillo, Marta; Reimann, Tony; Schütt, Brigitta

    2016-04-01

    Located in the arid basalt desert of northeastern Jordan, the Early Bronze Age (EBA) settlement of Jawa is by far the largest and best preserved archaeological EBA site in the region. Recent surveys in the close vicinity revealed well-preserved remains of three abandoned agricultural terrace systems. In the presented study these archaeological features are documented by detailed mapping and the analysis of the sediment records in a multi-proxy approach. To study the chronology of the terrace systems optically stimulated luminescence (OSL) is used. In order to evaluate the efficiency of the water management techniques and its impact on harvest yields, a crop simulation model (CropSyst) under today's climatic conditions is applied, simulating crop yields with and without (runoff) irrigation. In order to do so, a runoff time series for each agricultural terrace system and its catchment is generated, applying the SCS runoff curve number method (CN) based on rainfall and soil data. Covering a total area of 38 ha, irrigated terrace agriculture was practiced on slopes, small plateaus, and valleys in the close vicinity of Jawa. Floodwater from nearby wadis or runoff from adjacent slopes was collected and diverted via surface canals. The terraced fields were arranged in cascades, allowing effective water exploitation through a system of risers, canals and spillways. The examined terrace profiles show similar stratigraphic sequences of mixed unstratified fine sediments that are composed of small-scale relocated sediments with local origin. The accumulation of these fines is associated with the construction of agricultural terraces, forcing infiltration and storage of the water within the terraces. Two OSL ages of terrace fills indicate that the construction of these terrace systems started as early as 5300 ± 300 a, which fits well to the beginning of the occupation phase of Jawa at around 3.500 calBC, thus making them to the oldest examples of its kind in the Middle East

  17. Water Governance and Adaptation to Disturbances in Irrigated Semi-Arid Agricultural Systems

    NASA Astrophysics Data System (ADS)

    Evans, T. P.; McCord, P. F.; McBride, L.; Gower, D.; Caylor, K. K.

    2013-12-01

    Climate and other physical drivers of environmental systems are modifying the global availability of water for irrigation. At the same time population growth is placing an increased demand on water resources as local municipalities promote agricultural production as a mechanism to support human welfare and development. Substantial has research focused on household-level agricultural decision-making and adaptation. But equally important are institutional dynamics, or the rules implemented to allocate water resources across different user groups. Previous work has identified design principles for common-pool resource systems that tend to lead to sustained governance regimes. Likewise, past research has addressed the issue of "institutional fit", or locally adapted governance arrangements characterized through governance structure. However, much of the complexity behind institutional dynamics and adaptive capacity lies in the translation of data to information to knowledge, and how this sequence contributes to effective cross-scale water management and decision-making - an arena that has arguably received less attention in the water management literature. We investigate the interplay between governance regimes, data/information and institutional dynamics in irrigation systems in semi-arid regions of Kenya. In particular, we articulate the role of knowledge and data in institutional dynamics at multiple levels of analysis. How do users at different decision-making levels incorporate social and hydrological information in water governance? What data is needed to develop the information and knowledge users need for effective management? While governance structure is certainly a critical component of water management systems - we emphasize the interplay between the data-information-knowledge sequence and institutional dynamics. We present findings from household and manager-level surveys examining irrigation practices and the institutions designed to equitably allocate

  18. Eco-efficiency of agricultural water systems: Methodological approach and assessment at meso-level scale.

    PubMed

    Todorovic, Mladen; Mehmeti, Andi; Scardigno, Alessandra

    2016-01-01

    This study presents a methodological framework for the meso-level eco-efficiency assessment of agricultural water systems using a life-cycle system-based approach. The methodology was applied to the Sinistra Ofanto irrigation scheme, located in Southern Italy, where about 28,165 ha are under irrigation. The environmental performance of the system was evaluated through a set of selected mid-point environmental impact categories while the economic performance was measured using the total value added to the system's final products due to water use and the adopted management practices. Both economic performance and environmental performance were measured at different stages and for each stakeholder in the value chain. A distinction was made between foreground and background systems referring, respectively, to the processes that occurred inside the water system boundaries and those used for the production of supplementary resources. The analysis revealed that the major environmental burdens are: i) the freshwater resource depletion (i.e. excessive groundwater pumping), ii) climate change (i.e. direct emissions due to fertilizer use and diesel combustion), and iii) eutrophication (as a result of excessive application of N and P fertilizers). A considerable impact was observed on the background system where energy, fuel and agrochemicals were produced thereby confirming the prominent role of background processes in the comprehensive eco-efficiency assessment. The presented methodology aimed at the quantitative assessment of the eco-efficiency level rather than at the identification of the most affected environmental category. Hence, the results can be used to compare the performance of the system from one year to the next, among different stakeholders (water users) and/or to assess the impact of adopting innovative technologies and management practices. Moreover, the presented approach is useful for comparing the performance among different agricultural water systems and

  19. Eco-efficiency of agricultural water systems: Methodological approach and assessment at meso-level scale.

    PubMed

    Todorovic, Mladen; Mehmeti, Andi; Scardigno, Alessandra

    2016-01-01

    This study presents a methodological framework for the meso-level eco-efficiency assessment of agricultural water systems using a life-cycle system-based approach. The methodology was applied to the Sinistra Ofanto irrigation scheme, located in Southern Italy, where about 28,165 ha are under irrigation. The environmental performance of the system was evaluated through a set of selected mid-point environmental impact categories while the economic performance was measured using the total value added to the system's final products due to water use and the adopted management practices. Both economic performance and environmental performance were measured at different stages and for each stakeholder in the value chain. A distinction was made between foreground and background systems referring, respectively, to the processes that occurred inside the water system boundaries and those used for the production of supplementary resources. The analysis revealed that the major environmental burdens are: i) the freshwater resource depletion (i.e. excessive groundwater pumping), ii) climate change (i.e. direct emissions due to fertilizer use and diesel combustion), and iii) eutrophication (as a result of excessive application of N and P fertilizers). A considerable impact was observed on the background system where energy, fuel and agrochemicals were produced thereby confirming the prominent role of background processes in the comprehensive eco-efficiency assessment. The presented methodology aimed at the quantitative assessment of the eco-efficiency level rather than at the identification of the most affected environmental category. Hence, the results can be used to compare the performance of the system from one year to the next, among different stakeholders (water users) and/or to assess the impact of adopting innovative technologies and management practices. Moreover, the presented approach is useful for comparing the performance among different agricultural water systems and

  20. The Lower Sevier River Basin Crop Monitor and Forecast Decision Support System: Exploiting Landsat Imagery to Provide Continuous Information to Farmers and Water Managers

    NASA Astrophysics Data System (ADS)

    Torres-Rua, A. F.; Walker, W. R.; McKee, M.

    2013-12-01

    The last century has seen a large number of innovations in agriculture such as better policies for water control and management, upgraded water conveyance, irrigation, distribution, and monitoring systems, and better weather forecasting products. In spite of this, irrigation management and irrigation water deliveries by farmers/water managers is still based on factors like water share amounts, tradition, and past experience on irrigation. These factors are not necessarily related to the actual crop water use; they are followed because of the absence of related information provided in a timely manner at an affordable cost. Thus, it is necessary to develop means to deliver continuous and personalized information about crop water requirements to water users/managers at the field and irrigation system levels so managers at these levels can better quantify the required versus available water for irrigation during the irrigation season. This study presents a new decision support system (DSS) platform that addresses the absence of information on actual crop water requirements and crop performance by providing continuous updated farm-based crop water use along with other farm performance indicators such as crop yield and farm management to irrigators and water managers. This DSS exploits the periodicity of the Landsat Satellite Mission (8 to 16 days, depending on the period of interest) to provide remote monitoring at the individual field and irrigation system levels. The Landsat satellite images are converted into information about crop water use, yield performance and field management through application of state-of-the-art semi-physical and statistical algorithms that provide this information at a pixel basis that are ultimately aggregated to field and irrigation system levels. A version of the DSS has been implemented for the agricultural lands in the Lower Sevier River, Utah, and has been operational since the beginning of the 2013 irrigation season. The main goal of

  1. Measuring the Contribution of Agricultural Conservation Practices to Observed Trends and Recent Condition in Water Quality Indicators in Ohio, USA.

    PubMed

    Miltner, Robert J

    2015-11-01

    Over the last three decades, significant investments made to upgrade wastewater infrastructure and manage pollution from diffuse sources have resulted in measurably improved water quality and biological conditions in Ohio's rivers and streams. Conservation measures to reduce soil loss appear to have contributed significantly to the improvement witnessed over the last two decades and should therefore be continued. Within the most recent timeframe examined, little difference was found in either total phosphorus or suspended sediment concentration in relation to conservation measures, indicating that the environmental benefits of measures targeting soil loss may be approaching an asymptote. Conservation measures targeting livestock and forage management, however, appear to have reduced nitrogen concentrations within the recent time frame. An examination of the interrelationships between habitat quality, conservation measures, and land use indicated that water quality was generally mediated by interactions with stream habitat quality. However, the positive effect of habitat quality was reduced in catchments draining fine-textured soils. The implication of these latter two findings suggest that proscriptively adding natural function to the large network of ditched and maintained conveyances draining agricultural lands would substantially improve water quality, but management at the field level is necessary to minimize phosphorus losses.

  2. Characterization of Dissolved Solids in Water Resources of Agricultural Lands near Manila, Utah, 2004-05

    USGS Publications Warehouse

    Gerner, Steven J.; Spangler, L.E.; Kimball, B.A.; Naftz, D.L.

    2006-01-01

    Agricultural lands near Manila, Utah, have been identified as contributing dissolved solids to Flaming Gorge Reservoir. Concentrations of dissolved solids in water resources of agricultural lands near Manila, Utah, ranged from 35 to 7,410 milligrams per liter. The dissolved-solids load in seeps and drains in the study area that discharge to Flaming Gorge Reservoir ranged from less than 0.1 to 113 tons per day. The most substantial source of dissolved solids discharging from the study area to the reservoir was Birch Spring Draw. The mean daily dissolved-solids load near the mouth of Birch Spring Draw was 65 tons per day. The estimated annual dissolved-solids load imported to the study area by Sheep Creek and Peoples Canals is 1,330 and 13,200 tons, respectively. Daily dissolved-solid loads discharging to the reservoir from the study area, less the amount of dissolved solids imported by canals, for the period July 1, 2004, to June 30, 2005, ranged from 90 to 289 tons per day with a mean of 142 tons per day. The estimated annual dissolved-solids load discharging to the reservoir from the study area, less the amount of dissolved solids imported by canals, for the same period was 51,900 tons. Of this 51,900 tons of dissolved solids, about 9,000 tons may be from a regional source that is not associated with agricultural activities. The salt-loading factor is 3,670 milligrams per liter or about 5.0 tons of dissolved solids per acre-foot of deep percolation in Lucerne Valley and 1,620 milligrams per liter or 2.2 tons per acre-foot in South Valley. The variation of 87Sr with strontium concentration indicates some general patterns that help to define a conceptual model of the processes affecting the concentration of strontium and the 87Sr isotopic ratio in area waters. As excess irrigation water percolates through soils derived from Mancos Shale, the 87Sr isotopic ratio (0.21 to 0.69 permil) approaches one that is typical of deep percolation from irrigation on Mancos Shale

  3. Shallow ground-water quality in selected agricultural areas of south-central Georgia, 1994

    USGS Publications Warehouse

    Crandall, C.A.

    1996-01-01

    The Georgia-Florida Coastal Plain National Water-Quality Assessment Program began an agricultural land-use study in March 1994. The study area is located in the upper Suwannee River basin in Tift, Turner, Worth, Irwin, Wilcox, and Crisp Counties, Ga. Twenty-three shallow monitoring wells were installed in a 1,335-square- mile area characterized by intensive row-crop agriculture (peanuts, corn, cotton, and soybeans). The study focused on recently recharged shallow ground water in surficial aquifers to assess the relation between land-use activities and ground- water quality. All wells were sampled in March and April (spring) 1994, and 14 of these wells were resampled in August (summer) 1994. Shallow ground water in the study area is characterized by oxic and acidic conditions, low bicarbonate, and low dissolved-solids concentrations. The median pH of shallow ground water was 4.7 and the median bicarbonate concentration was 1.7 mg/L (milligrams per liter). Dissolved oxygen concentrations ranged from 3.0 to 8.0 mg/L. The median dissolved-solids concentration in samples collected in the spring was 86 mg/L. Major inorganic ion composition was generally mixed with no dominant cation; nitrate was the dominant anion (greater than 60 percent of the anion composition) in 14 of 23 samples. Only concentrations of bicarbonate, dissolved organic carbon, and nitrate had significant differences in concentrations between samples collected in the spring and the background samples. However, median concentrations of some of the major ingredients in fertilizer (including magnesium, chloride, nitrate, iron, and manganese) were higher in water samples from agricultural wells than in background samples. The median concentration of dissolved solids in ground-water samples collected in the spring (86 mg/L) was more than double the median concentration (41 mg/L) of the background samples. The median nitrate as nitrogen concentration of 6.7 mg/L in the spring samples reflects the effects of

  4. Organophosphate Pesticide Residues in Drinking Water from Artesian Wells and Health Risk Assessment of Agricultural Communities, Thailand.

    PubMed

    Jaipieam, S; Visuthismajarn, P; Sutheravut, P; Siriwong, W; Thoumsang, S; Borjan, M; Robson, M

    2009-01-01

    Organophosphate pesticide (OPPs) concentrations in artesian wells located in Thai agricultural and non-agricultural communities were studied during both wet and dry seasons. A total of 100 water samples were collected and subjects were asked to complete a survey. Gas chromatography flame photometric detector was used for OPP analysis. The average OPP concentration in the agricultural communities (0.085 and 0.418 microg/l in dry and wet season) was higher than in the non-agricultural communities (0.004 microg/l in both seasons). Ingestion of OPPs in contaminated water in the agricultural communities were estimated to be 0.187 and 0.919 microg/day during the dry and wet seasons, respectively, and 0.008 microg/day during both seasons in the non-agricultural communities. Agricultural communities were exposed to pesticide residues under the oral chronic reference dose. This study suggests that people in agricultural communities may be exposed to significantly greater levels of pesticides than non-agricultural populations during the dry and wet seasons (p < .001, .001).

  5. 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

  6. Water and sediment quality in a tropical swamp used for agricultural and oil refining activities.

    PubMed

    Norville, Wendy; Banjoo, Darryl

    2011-01-01

    The Godineau Swamp in Trinidad receives anthropogenic input from agricultural and oil refining activities, sewage and domestic waste. This study was conducted in order to provide a comprehensive baseline dataset for the swamp, to assess water and sediment quality in the swamp, and to identify hotspots and possible sources of pollutants to the swamp. Ten sampling stations were established in the swamp during April/May and July 2002. Water quality parameters monitored included physicochemical measurements (pH, temperature, dissolved oxygen and salinity), total suspended solids, and nutrients (ammonia, nitrites, nitrates and total phosphorus). Sediments were analyzed for hydrocarbons, heavy metals and total organic carbon. Temperatures and pH of water in the swamp were ambient; dissolved oxygen was low in many instances (<3 mg/L). In the dry season, there was saltwater intrusion along the Oropuche River up to the most easterly station. Levels of ammonia and phosphorus concentrations were suggestive of periodic inputs of agricultural and domestic wastes. Hydrocarbons concentrations in sediment were above ambient levels and suggestive of contamination from industrial activities. Sediments from the Godineau River contained elevated nutrients, hydrocarbons, metals and TOC compared with other stations. The results of this study indicate some degree of pollution of the Godineau swamp, which prompts the need for the implementation of measures beneficial for wise use of the swamp.

  7. Network for measuring runoff and water erosion in small agricultural cathments in Southern Spain

    NASA Astrophysics Data System (ADS)

    Taguas, E. V.; Gómez, J. A.; Boulal, H.; Gómez, H.; Vanwalleghem, T.; Pérez-Alcántara, R.; Peña, A.; Ayuso-Muñoz, J. L.; Giráldez, J. V.; Mateos, L.

    2010-05-01

    Water erosion is one of the major environmental threats to sustainability of agricultural production in Souther Spain. In Mediterranean climates, innapropriate soil management in steep or hilly landscapes causes intensive and extensive on-site and off-site damage. However, limited experimental information is available for fully understand the relationship between soil management practices and erosion at varying scales. This communication describes a network of five experimental catchments equipped with runoff and erosion monitoring devices established in the last five years in agricultural areas of Southern Spain. Three of the catchments are of small size (2 to 6.7 ha) and are covered by olive trees, a fourth one, of 20 ha, is cultivated with irrigated field crops, and the fifth catchment is located in an irrigation district where irrigated annual and tree crops coexist covering an area of 316 ha. Monitoring stations consist of a long-throated flume equipped with a untrasonic sensor to measure water depth, an ISCO water sampler, a rain gauge and a datalogger. This communication will present a preliminary comparison of runoff and sediment generated in the catchments during recent years, and it will discuss some of the main problems encountered in the establishment of the network and the future plans for upgrading the monitoring stations and analysing of results.

  8. Removal of selenium from contaminated agricultural drainage water by nanofiltration membranes

    USGS Publications Warehouse

    Kharaka, Y.K.; Ambats, G.; Presser, T.S.; Davis, R.A.

    1996-01-01

    Seleniferous agricultural drainage wastewater has become a new major source of pollution in the world. In the USA, large areas of farmland in 17 western states, generate contaminated salinized drainage with Se concentrations much higher than 5 ??g/l, the US Environmental Protection Agency water-quality criterion for the protection of aquatic life; Se values locally reach 4200 ??g/l in western San Joaquin Valley, California. Wetland habitats receiving this drainage have generally shown Se toxicosis in aquatic birds causing high rates of embryonic deformity and mortality, or have indicated potential ecological damage. Results of our laboratory flow experiments indicate that nanofiltration, the latest membrane separation technology, can selectively remove > 95% of Se and other multivalent anions from > 90% of highly contaminated water from the San Joaquin Valley, California. Such membranes yield greater water output and require lower pressures and less pretreatment, and therefore, are more cost effective than traditional reverse osmosis membranes. Nanofiltration membranes offer a potential breakthrough for the management of Se contaminated wastes not only from agricultural drainage, but from other sources also.

  9. Impacts of Biofuel-Induced Agricultural Land Use Changes on Watershed Hydrology and Water Quality

    NASA Astrophysics Data System (ADS)

    Lin, Z.; Zheng, H.

    2015-12-01

    The US Energy Independence and Security Act (EISA) of 2007 has contributed to widespread changes in agricultural land uses. The impact of these land use changes on regional water resources could also be significant. Agricultural land use changes were evaluated for the Red River of the North Basin (RRNB), an international river basin shared by the US and Canada. The influence of the land use changes on spring snowmelt flooding and downstream water quality was also assessed using watershed modeling. The planting areas for corn and soybean in the basin increased by 62% and 18%, while those for spring wheat, forest, and pasture decreased by 30%, 18%, and 50%, from 2006 to 2013. Although the magnitude of spring snowmelt peak flows in the Red River did not change from pre-EISA to post-EISA, our uncertainty analysis of the normalized hydrographs revealed that the downstream streamflows had a greater variability under the post-EISA land use scenario, which may lead to greater uncertainty in predicting spring snowmelt floods in the Red River. Hydrological simulation also showed that the sediment and nutrient loads at the basin's outlet in the US and Canada border increased under the post-EISA land use scenario, on average sediment increasing by 2.6%, TP by 14.1%, nitrate nitrogen by 5.9%, and TN by 9.1%. Potential impacts of the future biofuel crop scenarios on watershed hydrology and water quality in the RRNB were also simulated through integrated economic-hydrologic modeling.

  10. Demand driven decision support for efficient water resources allocation in irrigated agriculture

    NASA Astrophysics Data System (ADS)

    Schuetze, Niels; Grießbach, Ulrike Ulrike; Röhm, Patric; Stange, Peter; Wagner, Michael; Seidel, Sabine; Werisch, Stefan; Barfus, Klemens

    2014-05-01

    Due to climate change, extreme weather conditions, such as longer dry spells in the summer months, may have an increasing impact on the agriculture in Saxony (Eastern Germany). For this reason, and, additionally, declining amounts of rainfall during the growing season the use of irrigation will be more important in future in Eastern Germany. To cope with this higher demand of water, a new decision support framework is developed which focuses on an integrated management of both irrigation water supply and demand. For modeling the regional water demand, local (and site-specific) water demand functions are used which are derived from the optimized agronomic response at farms scale. To account for climate variability the agronomic response is represented by stochastic crop water production functions (SCWPF) which provide the estimated yield subject to the minimum amount of irrigation water. These functions take into account the different soil types, crops and stochastically generated climate scenarios. By applying mathematical interpolation and optimization techniques, the SCWPF's are used to compute the water demand considering different constraints, for instance variable and fix costs or the producer price. This generic approach enables the computation for both multiple crops at farm scale as well as of the aggregated response to water pricing at a regional scale for full and deficit irrigation systems. Within the SAPHIR (SAxonian Platform for High Performance Irrigation) project a prototype of a decision support system is developed which helps to evaluate combined water supply and demand management policies for an effective and efficient utilization of water in order to meet future demands. The prototype is implemented as a web-based decision support system and it is based on a service-oriented geo-database architecture.

  11. The Effect of Aquatic Vegetation on Water Quality in the Everglades Agricultural Area Canals

    NASA Astrophysics Data System (ADS)

    Gomez, S. M.; Bhadha, J. H.; Lang, T. A.; Josan, M. S.; Daroub, S. H.

    2011-12-01

    The canals in the Everglades Agricultural Area contain an abundance of floating aquatic vegetation (FAV) and submerged aquatic vegetation (SAV). These FAV flourish in waters with high phosphorus (P) concentrations and prevent the co-precipitation of P with the limestone bedrock (CaCO3). To test the effects of FAV and SAV and the presence of sediments on water quality in the canals, a lysimeter study was set up and stocked with FAV (water lettuce) and SAV (filamentous algae). There were four treatments with four replicates Treatment one contained limerock, sediment from the canals, and FAV. Treatment two contained limerock, sediment, and SAV. Treatment three contained limerock and FAV, while treatment four had limerock and SAV. After 7 days, the buckets were drained and replaced the water with new, high P canal water. Water samples were taken at 0, 0.25, 1, 3, and 7 days after each weekly water exchange. To test water quality soluble reactive P, total P, total dissolved P, Ca, and total organic carbon were analyzed. The impact of FAV and SAV and canal sediments on water quality will be discussed. We hypothesize water lettuce treatments will initially result in a reduction in P-concentration in all species, but will only serve as a short-term sink because of their high turn-over rate and production of labile high-P sediment (floc). In addition, we hypothesize the treatments with no sediment will have more P reduction because of the availability for P to co-precipitate with CaCO3.

  12. Paper versus plastic, water versus carbon and sustainable agriculture in the US

    NASA Astrophysics Data System (ADS)

    Bowling, L. C.

    2011-12-01

    It is increasingly recognized that food and energy security are inextricably linked to climate and climate change, resulting in the so-called climate, energy, food nexus, with the water cycle at its hub. The ability to provide sufficient and consistent energy and food for this generation, while not depleting soil, climate and water resources for future generations involves interconnected feedbacks along the paths of this wheel. In the US corn belt, for example, agricultural water management in the form of subsurface drainage lowers the regional water table to enhance crop production, while at the same time providing a conduit for the more efficient export of nitrate-nitrogen to the Gulf of Mexico and increasing rates of decomposition and subsidence in organic-rich soils. The use of control structures to regulate drainage water has the potential to reduce nitrate and carbon dioxide losses, while at the same time increasing the emissions of other greenhouse gases. Increased biofuels production offers the potential to increase domestic energy security, but at the cost of increased water demand and threats to food security. Just as budding US consumer environmentalists of the last decade struggled with the question of paper versus plastic for bagging their groceries, today's informed consumers are being asked to tacitly choose between water and carbon. The local foods movement encourages consumption of locally-produced foods as a means of reducing carbon emissions associated with food transportation, among other perceived benefits. At the same time, the concept of virtual water trade recognizes that importing the water embedded in production in the form of food can balance a local water deficit. Taking into account the virtual water of food production and carbon emissions of food transportation, the spatial arrangement of the current US crop portfolio minimizes neither water nor carbon footprints. Changes in crop distribution result in trade-offs between the per capita

  13. Long-term fluctuations of water resources availability and its implications for a sustainable management of arid agricultural coastal regions

    NASA Astrophysics Data System (ADS)

    Grundmann, Jens; Schütze, Niels

    2015-04-01

    Freshwater scarcity and ongoing population growth associated with increasing water demands are major challenges for water management in coastal arid regions. Excessive use of groundwater for irrigation in agriculture puts those regions at risk of saltwater intrusion which limits agricultural opportunities. Additionally, some arid regions are characterised by a cyclic climate in which longer periods of dry years are followed by longer periods of wet years. This results also in long-term fluctuations of groundwater replenishment rates and water resources availability which may reach the same order of magnitude like long-term average values. Therefore, these long-term fluctuations should be considered for water resources management planning and operation. In order to evaluate their impact a simulation-based integrated water management system for coastal arid regions is used. The management system couples a groundwater module, assessing the water resources availability, and an agricultural module, controlling irrigation and cultivation within an optimisation module which allow for multi-objective optimisation of the water management regarding profitable and sustainable water resources and agricultural management on farm and regional scale. To achieve a fast and robust operation of the water management system, surrogate models are used which emulate the behaviour of physically based process models and a hierarchical optimisation scheme is applied. The water management system is driven by different scenarios of the water resources availability which were generated by using time series analyses and modelling of local groundwater replenishment rates. An application is performed for the south Batinah coastal region in the Sultanate of Oman which is affected by saltwater intrusion into a coastal aquifer system due to excessive groundwater withdrawal for irrigated agriculture. Several scenarios of water resources availability are used to compare long-term and adaptive

  14. Reconnaissance of water quality in the High Plains Aquifer beneath agricultural lands, south-central Kansas

    USGS Publications Warehouse

    Stullken, L.E.; Stamer, J.K.; Carr, J.E.

    1987-01-01

    The High Plains of western Kansas was one of 14 areas selected for preliminary groundwater quality reconnaissance by the U.S. Geological Survey 's Toxic Waste--Groundwater Contamination Program. The specific objective was to evaluate the effects of land used for agriculture (irrigated cropland and non-irrigated rangeland) on the water in the High Plains aquifer. Conceptual inferences, based on the information available, would lead one to expect groundwater beneath irrigated cropland to contain larger concentrations of sodium, sulfate, chloride, nitrite plus nitrate, and some water soluble pesticides than water beneath non-irrigated land (range-land) The central part of the Great Bend Prairie, an area of about 1,800 sq mi overlying the High Plains aquifer in south-central Kansas, was selected for the study of agricultural land use because it has sand soils, a shallow water table, relatively large annual precipitation, and includes large areas that are exclusively irrigated cropland or non-irrigated rangeland. As determined by a two-tailed Wilcoxon rank-sum test, concentrations of sodium and alkalinity were significantly larger at the 95% confidence level for water samples from beneath irrigated cropland than from beneath rangeland. No statistically significant difference in concentrations of sulfate, chloride, nitrite plus nitrate, and ammonia, was detected. Concentrations of 2,4-D found in water samples from beneath the rangeland were larger at the 99% confidence level as compared to concentrations of 2,4-D in samples from beneath irrigated cropland. Larger concentrations of sodium and alkalinity were found in water beneath irrigated cropland, and the largest concentration of the pesticide atrazine (triazines were found in three samples) was found in water from the only irrigation well sampled. The sodium and atrazine concentrations found in water from the irrigation well support the premise that water-level drawdown develops under irrigated fields. This diverts

  15. Pretreatment of agriculture field water for improving membrane flux during pesticide removal

    NASA Astrophysics Data System (ADS)

    Mehta, Romil; Saha, N. K.; Bhattacharya, A.

    2016-09-01

    Pretreatment of feed water to improve membrane flux during filtration of agriculture field water containing substituted phenyl urea pesticide diuron has been reported. Laboratory-made reverse osmosis membrane was used for filtration. Preliminary experiments were conducted with model solution containing natural organic matter extracted from commercial humic acids, divalent ions Ca2+, Mg2+. Membrane fouling was characterized by pure water flux decline, change in membrane hydrophilicity and infrared spectroscopy. Natural organic matter present in field water causes severe membrane fouling. The presence of divalent cations further aggravated fouling. Use of ethylenediaminetetraacetic acid (EDTA) and polyacrylic acids (PAA) in feed resulted in the decrease in membrane fouling. Pretreatment of field water is a must if it is contaminated with micro-organism having membrane fouling potential. Feed water pretreatment and use of PAA restricted membrane fouling to 16 % after 60 h of filtration. Membrane permeate flux decline was maximum at the first 12 h and thereafter remained steady at around 45-46 lm-2h-1 till the end of 60 h. Diuron rejection remained consistently greater than 93 % throughout the experiment. Diuron rejection was found to be unaffected by membrane fouling.

  16. Black water sludge reuse in agriculture: are heavy metals a problem?

    PubMed

    Tervahauta, Taina; Rani, Sonia; Hernández Leal, Lucía; Buisman, Cees J N; Zeeman, Grietje

    2014-06-15

    Heavy metal content of sewage sludge is currently the most significant factor limiting its reuse in agriculture within the European Union. In the Netherlands most of the produced sewage sludge is incinerated, mineralizing the organic carbon into the atmosphere rather than returning it back to the soil. Source-separation of black water (toilet water) excludes external heavy metal inputs, such as industrial effluents and surface run-offs, producing sludge with reduced heavy metal content that is a more favorable source for resource recovery. The results presented in this paper show that feces is the main contributor to the heavy metal loading of vacuum collected black water (52-84%), while in sewage the contribution of feces is less than 10%. To distinguish black water from sewage in the sludge reuse regulation, a control parameter should be implemented, such as the Hg and Pb content that is significantly higher in sewage sludge compared to black water sludge (from 50- to 200-fold). The heavy metals in feces and urine are primarily from dietary sources, and promotion of the soil application of black water sludge over livestock manure and artificial fertilizers could further reduce the heavy metal content in the soil/food cycle.

  17. Natural radioactivity levels of geothermal waters and their influence on soil and agricultural activities.

    PubMed

    Murat Saç, Müslim; Aydemir, Sercan; Içhedef, Mutlu; Kumru, Mehmet N; Bolca, Mustafa; Ozen, Fulsen

    2014-01-01

    All over the world geothermal sources are used for different purposes. The contents of these waters are important to understand positive/negative effects on human life. In this study, natural radioactivity concentrations of geothermal waters were investigated to evaluate the effect on soils and agricultural activities. Geothermal water samples were collected from the Seferihisar Geothermal Region, and the radon and radium concentrations of these waters were analysed using a collector chamber method. Also soil samples, which are irrigated with geothermal waters, were collected from the surroundings of geothermal areas, and natural radioactivity concentrations of collected samples (U, Th and K) were determined using an NaI(Tl) detector system. The activity concentrations of radon and radium were found to be 0.6-6.0 and 0.1-1.0 Bq l(-1), respectively. Generally, the obtained results are not higher compared with the geothermal waters of the world. The activity concentrations in soils were found to be in the range of 3.3-120.3 Bq kg(-1) for (226)Ra (eU), 0.3-108.5 Bq kg(-1) for (232)Th (eTh), 116.0-850.0 Bq kg(-1) for (40)K (% K).

  18. A preliminary appraisal of the impact of agriculture on ground-water availability in Southwest Georgia

    USGS Publications Warehouse

    Pollard, L.D.; Grantham, R.G.; Blanchard, H.E.

    1978-01-01

    Irrigated acreage in the 20-county study area in southwest Georgia increased from 130,000 acres in 1976 to 261,000 in 1977. Acreage irrigated entirely by ground water increased 85 percent for the same period. The largest quantity of ground water used for irrigation was in the Dougherty Plain district, where 92 percent of supplemental irrigation water comes from wells. The total amount of water pumped for irrigation in the Dougherty Plain in 1977 was more than 42 billion gallons, 30 billion gallons more than in 1976. There were no detectable concentrations of selected organic compounds and trace metals used in agricultural chemicals above the recommended limits for public consumption in 19 wells sampled for chemical analyses. Although nitrate concentrations were not above the recommended limits for drinking water, the presence of nitrate in amounts ranging from 0.3 to 7.8 milligrams per liter in wells in the Dougherty Plain possibly indicate the downward movement of soluble nitrate, a byproduct of fertilizer, into the ground-water reservoir. (Woodard-USGS)

  19. Climate Change Impacts and Adaptation on Water Resources and Agricultural Diversity of the Upper Rio Grande Watershed

    NASA Astrophysics Data System (ADS)

    Rouhi Rad, M.; Hurd, B. H.

    2012-12-01

    Climate change can alter the balance of the water resources systems. It can both change the amount and the timing of the streamflow available in a basin and the amount of water consumed at the end point due to higher temperatures. These changes in the supply and demand sides can result in a different allocation of water and different price for water in basin scale based on economic principles. In a previous study Hurd and Coonrod (2012) modeled the impacts of climate change on the water related economic activities of the Rio Grande. In their study they assumed an aggregated benefit function for the agricultural sector. In another study on the Rio Grande Brinegar and Ward (2009) modeled the agricultural diversity of the Rio Grande within the framework of a hydro-economic model. This study builds upon and extends the previous studies by developing a model that can more carefully assess the role of adaptation in agriculture. Specially, the current study adds quadratic production functions for each crop. These production functions add a major benefit to the modeling of the hydro-economic system, namely that of adding diversity and expanded resolution to the agricultural sector. Using this production function the model includes both land and water as independent variables in the agricultural sector and, therefore this extension of the model has more flexibility to represent adaptive responses to climatic changes by including the capacity to change the crop mix and acreages as well as the water applied i.e. the capacity to deficit irrigate. The results of this study show that the agricultural sector can lose nearly a third of its water and more than 30% of its net economic benefits as a result of possible climate changes. It also shows as the climate become drier and population grows then economic forces will encourage agriculture to move towards more beneficial crops and reduce total acreage and in some cases applied water.

  20. SIMPLE: assessment of non-point phosphorus pollution from agricultural land to surface waters by means of a new methodology.

    PubMed

    Schoumans, O F; Mol-Dijkstra, J; Akkermans, L M W; Roest, C W J

    2002-01-01

    In the past, environmental Phosphorus (P) parameters like soil P indices have been used to catogorize the potential risk of P losses from agricultural land. In order to assess the actual risk of P pollution of groundwater and surface waters, dynamic process oriented soil and water quality models have been frequently used. Recently, an approximating model for phosphorus, called SIMPLE, has been developed. This model approximates the output from a complex dynamic water quality model. The approximating model is called a metamodel. This simple P-model proves to be a powerful tool for quick assessment of the risk of P pollution from agricultural land to surface waters. PMID:12079100

  1. Continuous Water-Quality Monitoring of Streams in Johnson County, Kansas, 2002-06

    USGS Publications Warehouse

    Rasmussen, Teresa J.; Lee, Casey J.; Ziegler, Andrew C.

    2008-01-01

    Water quality in Johnson County, Kansas was characterized on the basis of continuous, in-stream monitoring. The results summarized in this fact sheet may be used to better understand concentration and load variability during changing seasonal and streamflow conditions and to assess water-quality conditions relative to water-quality standards and management goals. The baseline information also will be useful for evaluating future changes in land use and effectiveness of implemented best management practices.

  2. Real-time, continuous water-quality monitoring in Indiana and Kentucky

    USGS Publications Warehouse

    Shoda, Megan E.; Lathrop, Timothy R.; Risch, Martin R.

    2015-01-01

    Water-quality “super” gages (also known as “sentry” gages) provide real-time, continuous measurements of the physical and chemical characteristics of stream water at or near selected U.S. Geological Survey (USGS) streamgages in Indiana and Kentucky. A super gage includes streamflow and water-quality instrumentation and representative stream sample collection for laboratory analysis. USGS scientists can use statistical surrogate models to relate instrument values to analyzed chemical concentrations at a super gage. Real-time, continuous and laboratory-analyzed concentration and load data are publicly accessible on USGS Web pages.

  3. Water for food and nature in drought-prone tropics: vapour shift in rain-fed agriculture.

    PubMed Central

    Rockström, Johan

    2003-01-01

    This paper quantifies the eco-hydrological challenge up until 2050 of producing food in balance with goods and services generated by water-dependent ecosystems in nature. Particular focus is given to the savannah zone, covering 40% of the land area in the world, where water scarcity constitutes a serious constraint to sustainable development. The analysis indicates an urgent need for a new green revolution, which focuses on upgrading rain-fed agriculture. Water requirements to produce adequate diets for humans are shown to be relatively generic irrespective of hydro-climate, amounting to a global average of 1,300 m(3) cap(-1) yr(-1). Present food production requires an estimated 6,800 km(3) yr(-1) of consumptive green water (5,000 km(3) yr(-1) in rain-fed agriculture and 1,800 km(3) yr(-1) from irrigated crops). Without considering water productivity gains, an additional 5,800 km(3) yr(-1) of water is needed to feed a growing population in 2,050 and eradicate malnutrition. It is shown that the bulk of this water will be used in rain-fed agriculture. A dynamic analysis of water productivity and management options indicates that large 'crop per drop' improvements can be achieved at the farm level. Vapour shift in favour of productive green water flow as crop transpiration could result in relative water savings of 500 km(3) yr(-1) in semi-arid rain-fed agriculture. PMID:14728794

  4. CoWS: Continuous Water Sampler for CRDS-based, real-time measurements of water isotopes

    NASA Astrophysics Data System (ADS)

    Carter, J.; Huang, K.; Dennis, K. J.

    2014-12-01

    Stable isotopes of water (δ18O and δD) are unique tracers for studying hydrological and associated processes. High spatial and temporal resolution measurements of water isotopes are necessary to follow the dynamics in rapidly changing systems and to map out the spatial heterogeneity of water circulation and mixing. Here we present results of the first commercially available Continuous Water Sampler Module (CoWS) that can be coupled to a Picarro L2130-i Cavity Ring-Down Spectrometer (CRDS) for real-time measurements of water isotopes. The CoWS is a compact and fully automated system with its core method modified from that of Munksgaard et al. (2011). Liquid water is continuously pumped into an extraction chamber, where water vapor diffuses through a micro-poruous polytetrafluoroethylene (ePTFE) membrane. The vapor is then carried by a dry carrier gas to the L2130-i for high precision measurements of δ18O and δD. The inlet water, carrier gas, and surface of the ePTFE membrane are actively temperature controlled to maintain a stable amount of fractionation of water isotopes across the membrane, which minimizes measurement drift. We have tested the CoWS-CRDS system with various inlet water types (tap water, deionized water, and seawater), and under operational conditions with variable ambient water and air temperatures. CoWS-CRDS has high precision (< 0.05 and < 0.15 ‰ 1σ, 5 minute average for δ18O and δD, respectively) and low drift water isotope measurements, with short response time (<5 minutes to eliminate 98% of the memory). The CoWS software is user configurable; allowing automated sampling among up to four water sources with user defined sampling durations. Additionally, we will present isotopic measurements with high-temporal resolution of an estuarine system where tidal changes affected the isotopic composition of the estuary.

  5. Methodology for assessing quantities of water and proppant injection, and water production associated with development of continuous petroleum accumulations

    USGS Publications Warehouse

    Haines, Seth S.

    2015-07-13

    The quantities of water and hydraulic fracturing proppant required for producing petroleum (oil, gas, and natural gas liquids) from continuous accumulations, and the quantities of water extracted during petroleum production, can be quantitatively assessed using a probabilistic approach. The water and proppant assessment methodology builds on the U.S. Geological Survey methodology for quantitative assessment of undiscovered technically recoverable petroleum resources in continuous accumulations. The U.S. Geological Survey assessment methodology for continuous petroleum accumulations includes fundamental concepts such as geologically defined assessment units, and probabilistic input values including well-drainage area, sweet- and non-sweet-spot areas, and success ratio within the untested area of each assessment unit. In addition to petroleum-related information, required inputs for the water and proppant assessment methodology include probabilistic estimates of per-well water usage for drilling, cementing, and hydraulic-fracture stimulation; the ratio of proppant to water for hydraulic fracturing; the percentage of hydraulic fracturing water that returns to the surface as flowback; and the ratio of produced water to petroleum over the productive life of each well. Water and proppant assessments combine information from recent or current petroleum assessments with water- and proppant-related input values for the assessment unit being studied, using Monte Carlo simulation, to yield probabilistic estimates of the volume of water for drilling, cementing, and hydraulic fracture stimulation; the quantity of proppant for hydraulic fracture stimulation; and the volumes of water produced as flowback shortly after well completion, and produced over the life of the well.

  6. [Pesticide residues in drinking water of an agricultural community in the state of Mérida, Venezuela].

    PubMed

    Flores-García, Mery Elisa; Molina-Morales, Yuri; Balza-Quintero, Alirio; Benítez-Díaz, Pedro Rafael; Miranda-Contreras, Leticia

    2011-12-01

    The aim of this study was to determine the presence of pesticides in drinking water from six aqueducts in a region of intense agricultural activity in the state of Merida, Venezuela. The study was conducted for four continuous weeks, between May and June 2008. Pesticide residues were analyzed by solid phase extraction (SPE) and liquid chromatography (HPLC) with diode array detector (DAD). The method SPE-HPLC-DAD met the criteria of analytical validation, with good linearity (R2: 0.9840 to 0.9999), precision (coefficient of inter-day variability from 1.47 to 6.25%), accuracy (relative standard deviation 0.9 to 9.20%) and sensitivity (LOD < or = 0.012 microg/L; LOQ < or = 0.030 microg/L, except mancozeb with 0.400 microg/L). Seven of the thirteen selected pesticides have a recovery rate between 100% and 70%, the rest between 61% and 37%. Ten pesticides of the following chemical groups, were detected in 72 samples analyzed: organophosphates, carbamates, triazines and urea derivatives. The pesticides with the highest frequency of detection were: carbofuran and atrazine (39%), malathion (25%), dimethoate and metribuzin (19%). The pesticides found at high levels were diazinon (26.31 microg/L), methamidophos (10.99 microg/L), malathion (2.03 microg/L) and mancozeb (1.27 microg/L). Pesticide levels did not exceed the maximum allowed by Venezuelan law, however, according to international standards (EU and EPA-USA) values were above the maximum permissible levels. This study demonstrates the urgent need for systematic monitoring of the quality of water for human consumption in regions of high agricultural productivity. PMID:22523840

  7. [Pesticide residues in drinking water of an agricultural community in the state of Mérida, Venezuela].

    PubMed

    Flores-García, Mery Elisa; Molina-Morales, Yuri; Balza-Quintero, Alirio; Benítez-Díaz, Pedro Rafael; Miranda-Contreras, Leticia

    2011-12-01

    The aim of this study was to determine the presence of pesticides in drinking water from six aqueducts in a region of intense agricultural activity in the state of Merida, Venezuela. The study was conducted for four continuous weeks, between May and June 2008. Pesticide residues were analyzed by solid phase extraction (SPE) and liquid chromatography (HPLC) with diode array detector (DAD). The method SPE-HPLC-DAD met the criteria of analytical validation, with good linearity (R2: 0.9840 to 0.9999), precision (coefficient of inter-day variability from 1.47 to 6.25%), accuracy (relative standard deviation 0.9 to 9.20%) and sensitivity (LOD < or = 0.012 microg/L; LOQ < or = 0.030 microg/L, except mancozeb with 0.400 microg/L). Seven of the thirteen selected pesticides have a recovery rate between 100% and 70%, the rest between 61% and 37%. Ten pesticides of the following chemical groups, were detected in 72 samples analyzed: organophosphates, carbamates, triazines and urea derivatives. The pesticides with the highest frequency of detection were: carbofuran and atrazine (39%), malathion (25%), dimethoate and metribuzin (19%). The pesticides found at high levels were diazinon (26.31 microg/L), methamidophos (10.99 microg/L), malathion (2.03 microg/L) and mancozeb (1.27 microg/L). Pesticide levels did not exceed the maximum allowed by Venezuelan law, however, according to international standards (EU and EPA-USA) values were above the maximum permissible levels. This study demonstrates the urgent need for systematic monitoring of the quality of water for human consumption in regions of high agricultural productivity.

  8. 2014 ISS Potable Water Characterization and Continuation of the DMSD Chronicle

    NASA Technical Reports Server (NTRS)

    Straub, John E., II; Plumlee, Debrah K.; Mudgett, Paul D.

    2015-01-01

    During 2014 the crews from Expeditions 38-41 were resident on the International Space Station (ISS). In addition to the U.S. potable water reclaimed from humidity condensate and urine, the other water supplies available for their use were Russian potable water reclaimed from condensate and Russian ground-supplied potable water. Beginning in June of 2014, and for the fourth time since 2010, the product water from the U.S. Water Processor Assembly (WPA) experienced a rise in the total organic carbon (TOC) level due to organic contaminants breaking through the water treatment process. Results from ground analyses of ISS archival water samples returned on Soyuz 38 confirmed that dimethylsilanediol (DMSD) was once again the contaminant responsible for the rise. With this confirmation in hand and based upon the low toxicity of DMSD, a waiver was approved to allow the crew to continue to consume the water after the TOC level exceeded the U.S. Segment limit of 3 mg/L. Several weeks after the WPA multifiltration beds were replaced, as anticipated based upon experience from previous rises, the TOC levels returned to below the method detection limit of the onboard TOC analyzer (TOCA). This paper presents and discusses the chemical analysis results for the ISS archival potable water samples returned in 2014 and analyzed by the Johnson Space Center's Toxicology and Environmental Chemistry laboratory. These results showed compliance with ISS potable water quality standards and indicated that the potable water supplies were acceptable for crew consumption. Although DMSD levels were at times elevated they remained well below the 35 mg/L health limit, so continued consumption of the U.S potable water was considered a low risk to crew health and safety. Excellent agreement between inflight and archival sample TOC data confirmed that the TOCA performed optimally and it continued to serve as a vital tool for monitoring organic breakthrough and planning remediation action.

  9. Sensitivity of water balance and water use efficiency to climate and crop type at an agricultural site

    NASA Astrophysics Data System (ADS)

    Brümmer, C.; Kutsch, W. L.

    2012-04-01

    The effects of climatic factors and crop type on evapotranspiration (E) and water use efficiency (WUE) were analyzed using tower-based eddy-covariance data for an agricultural site in Thuringia, Germany. During ten years of observation, winter wheat (five times) and winter barley (once) were alternately planted with potato (twice), rapeseed (once) and sugar beet (once). The seasonal pattern of E was closely linked to growing-season length and rainfall distribution. Although annual precipitation (P) was highly variable (380-700 mm), minimum annual E was not less than 250 mm and was limited to 380 mm. However, a positive correlation between annual P and annual E with E plateauing at high P as was usually found at forest, grassland and peatland sites could not be observed. Winter wheat tended to limit annual E and was found to be relatively insensitive with changing annual P and solar irradiance. A hysteretic relationship between monthly mean values of E and net radiation (Rn) indicated that E lagged behind the typical seasonal progression of Rn. Annual means of daytime dry-foliage Priestley-Taylor α much less than the theoretical maximum of 1.26 for extensive well-watered vegetation showed that E on an annual basis was either water limited and/or stomatal control of transpiration must have been prevalent. In all years, a strong linear correlation between monthly mean values of gross primary production and E resulted in WUE being relatively constant between 2.5 and 3.5 g C kg-1 H2O. Our study shows that crop selection has a major impact on the water balance of an agricultural site with the influence of climatic factors being significantly different than usually found for natural ecosystems.

  10. Multimodeling Framework for Predicting Water Quality in Fragmented Agriculture-Forest Ecosystems

    NASA Astrophysics Data System (ADS)

    Rose, J. B.; Guber, A.; Porter, W. F.; Williams, D.; Tamrakar, S.; Dechen Quinn, A.

    2012-12-01

    Both livestock and wildlife are major contributors of nonpoint pollution of surface water bodies. The interactions among them can substantially increase the chance of contamination especially in fragmented agriculture-forest landscapes, where wildlife (e.g. white tailed deer) can transmit diseases between remote farms. Unfortunately, models currently available for predicting fate and transport of microorganisms in these ecosystems do not account for such interactions. The objectives of this study are to develop and test a multimodeling framework that assesses the risk of microbial contamination of surface water caused by wildlife-livestock interactions in fragmented agriculture-forest ecosystems. The framework consists of a modified Soil Water Assessment Tool (SWAT), KINematic Runoff and EROSion model (KINEROS2) with the add-on module STWIR (Microorganism Transport with Infiltration and Runoff), RAMAS GIS, SIR compartmental model and Quantitative Microbial Risk Assessment model (QMRA). The watershed-scale model SWAT simulates plant biomass growth, wash-off of microorganisms from foliage and soil, overland and in-stream microbial transport, microbial growth, and die-off in foliage and soil. RAMAS GIS model predicts the most probable habitat and subsequent population of white-tailed deer based on land use and crop biomass. KINEROS-STWIR simulates overland transport of microorganisms released from soil, surface applied manure, and fecal deposits during runoff events at high temporal and special resolutions. KINEROS-STWIR and RAMAS GIS provide input for an SIR compartmental model which simulates disease transmission within and between deer groups. This information is used in SWAT model to account for transmission and deposition of pathogens by white tailed deer in stream water, foliage and soil. The QMRA approach extends to microorganisms inactivated in forage and water consumed by deer. Probabilities of deer infections and numbers of infected animals are computed

  11. The Role of Windbreaks in Reducing Water Resources Use in Irrigated Agriculture

    NASA Astrophysics Data System (ADS)

    Cochrane, T. A.; de Vries, T. T.

    2014-12-01

    Windbreaks are common features in flat agricultural landscapes around the world. The reduction in wind speed afforded by windbreaks is dictated by their porosity, location, height, and distance from the windbreak. The reduction in wind speeds not only reduces potential wind erosion; it also reduces crop evapotranspiration (ET) and provides shelter for livestock and crops. In the Canterbury plains of New Zealand there are over 300,000 km of windbreaks which were first implemented as a soil conservation strategy to reduce wind erosion of prime agricultural land. Agriculture in the region has since changed to irrigated pasture cultivation for dairy production and windbreaks are being cut down or reduced to heights of 2 m to allow for large scale centre-pivot irrigation schemes. Although soil erosion is no longer a major concern due to permanent pasture cover, irrigation water is sourced from limited supplies of ground and surface water and thus the effects of wind on irrigation losses due to spray drift and increased ET are of significant concern. The impact of reducing windbreaks needs to be understood in terms of water resources use. Experimental and theoretical work was conducted to quantify the reduction in wind speeds by windbreaks and in spray evaporation losses. A temporal and spatial model was also developed and validated to quantify the impact of single and multiple windbreaks on irrigation water losses. Initial modelling results show that for hot windy dry conditions in Canterbury, ET can increase by up to 1.4 mm/day when windbreaks are reduced to 2 m in height and on average wind days ET can increase by up to 0.5 mm/day. ET can be reduced by up to 30% in the windbreak leeward zone relative to ET in areas not protected by windbreaks. Wind speed, air temperature and relative humidity all had a considerable impact on spray evaporation losses, but the extent is determined by the droplet size. Estimated losses range from only 0.07% to 67% for 5 and 0.2 mm

  12. Climate change and its effect on agriculture, water resources and human health sectors in Poland

    NASA Astrophysics Data System (ADS)

    Szwed, M.; Karg, G.; Pińskwar, I.; Radziejewski, M.; Graczyk, D.; Kedziora, A.; Kundzewicz, Z. W.

    2010-08-01

    Multi-model ensemble climate projections in the ENSEMBLES Project of the EU allowed the authors to quantify selected extreme-weather indices for Poland, of importance to climate impacts on systems and sectors. Among indices were: number of days in a year with high value of the heat index; with high maximum and minimum temperatures; length of vegetation period; and number of consecutive dry days. Agricultural, hydrological, and human health indices were applied to evaluate the changing risk of weather extremes in Poland in three sectors. To achieve this, model-based simulations were compared for two time horizons, a century apart, i.e., 1961-1990 and 2061-2090. Climate changes, and in particular increases in temperature and changes in rainfall, have strong impacts on agriculture via weather extremes - droughts and heat waves. The crop yield depends particularly on water availability in the plant development phase. To estimate the changes in present and future yield of two crops important for Polish agriculture i.e., potatoes and wheat, some simple empirical models were used. For these crops, decrease of yield is projected for most of the country, with national means of yield change being: -2.175 t/ha for potatoes and -0.539 t/ha for wheat. Already now, in most of Poland, evapotranspiration exceeds precipitation during summer, hence the water storage (in surface water bodies, soil and ground) decreases. Summer precipitation deficit is projected to increase considerably in the future. The additional water supplies (above precipitation) needed to use the agro-potential of the environment would increase by half. Analysis of water balance components (now and in the projected future) can corroborate such conclusions. As regards climate and health, a composite index, proposed in this paper, is a product of the number of senior discomfort days and the number of seniors (aged 65+). The value of this index is projected to increase over 8-fold during 100 years. This is an

  13. [Strategy of grain yield stability cooperated with harmonious water environment quality of small agricultural watershed].

    PubMed

    Zeng, Zhao-xia; Liu, Xiao-li; Wang, Ke-lin; Zeng, Fu-ping; Song, Tong-qing; Song, Xi-juan

    2010-08-01

    This paper investigated the spatial variability of the correlations between grain yields and fertilization quantity within the selected agricultural watershed, in the typical black soil region, and then optimized the fertilization quantity at different landscape farmlands within the watershed based on the regression equations. Study simulated the surface runoff water quality before and after fertilization spatial adjustment with the achieved parameters by Soil and Water Assessment Tool (SWAT) model. The results showed that watershed scale fertilization adjustment is possible and necessary according to the spatial heterogeneity about fertilization and grain yields. Based on grain yield stability, spatial adjustment of fertilization reduced the whole watershed total N fertilization quantity by 1.88%, and the total non-point nutrients load reduction of NH4+ -N and NO3- -N was 9.7%, 5.6%, respectively.

  14. Arsenic contamination of soils and agricultural plants through irrigation water in Nepal.

    PubMed

    Dahal, B M; Fuerhacker, M; Mentler, A; Karki, K B; Shrestha, R R; Blum, W E H

    2008-09-01

    This study monitored the influence of arsenic-contaminated irrigation water on alkaline soils and arsenic uptake in agricultural plants at field level. The arsenic concentrations in irrigation water ranges from <0.005 to 1.014 mg L(-1) where the arsenic concentrations in the soils were measured from 6.1 to 16.7 mg As kg(-1). The arsenic content in different parts of plants are found in the order of roots>shoots>leaves>edible parts. The mean arsenic content of edible plant material (dry weight) were found in the order of onion leaves (0.55 mg As kg(-1))>onion bulb (0.45 mg As kg(-1))>cauliflower (0.33 mg As kg(-1))>rice (0.18 mg As kg(-1))>brinjal (0.09 mg As kg(-1))>potato (<0.01 mg As kg(-1)). PMID:18068879

  15. Assessing future risks to agricultural productivity, water resources and food security: How can remote sensing help?

    USGS Publications Warehouse

    Thenkabail, Prasad S.; Knox, Jerry W.; Ozdogan, Mutlu; Gumma, Murali Krishna; Congalton, Russell G.; Wu, Zhuoting; Milesi, Cristina; Finkral, Alex; Marshall, Mike; Mariotto, Isabella; You, Songcai; Giri, Chandra; Nagler, Pamela

    2012-01-01

    of changing dietary consumption patterns, a changing climate and the growing scarcity of water and land (Beddington, 2010). The impact from these changes wi ll affect the viability of both dryland subsistence and irrigated commodity food production (Knox, et al., 2010a). Since climate is a primary determinant of agricultural productivity, any changes will influence not only crop yields, but also the hydrologic balances, and supplies of inputs to managed farming systems as well as potentially shifting the geographic location for specific crops . Unless concerted and collective action is taken, society risks worldwide food shortages, scarcity of water resources and insufficient energy. This has the potential to unleash public unrest, cross-border conflicts and migration as people flee the worst-affected regions to seck refuge in "safe havens", a situation that Beddington described as the "perfect storm" (2010).

  16. Spatial Analysis Of Pesticide Use In Agriculture And Emissions To Water

    NASA Astrophysics Data System (ADS)

    Seuntjens, Piet; Van Esch, Leen; Joris, Ingeborg; Guy, Engelen; Stijn, Overloop

    2013-04-01

    For over more than a decade, concentrations of plant protection products in surface water have been monitored in Flanders. Some active substances are detected frequently (in up to 94% of monitoring locations for some substances) in surface water and exceedance of legal limits occurs regularly (up to 22% of monitoring locations depending on the substance). The aim of this study is to investigate the relationship between the use of plant protection products in agriculture and the impact on surface water quality. Their emissions towards the surface water are calculated with a high spatial resolution and compared to measured surface water concentrations. In a first step, the spatial distribution of the agricultural use of plant protection products is estimated from detailed crop maps for Flanders, combined with results from a survey on the use by farmers on different crops. Crops are aggregated to 12 different crop groups and 22 substances are investigated in the study. Relevant combinations of active substances and crop groups are defined, based on the survey, a consultation of authorized products and expert knowledge. All this information has been extrapolated to Flanders using among others spatial correlation techniques. This results in 12 raster maps with a resolution of 1 hectare, where every map represents the spatial distribution of the yearly use of a specific active substance for the whole of Flanders, taking the crop differences into account. Next, emission factors are calculated for different transport routes: drift, direct losses, volitilization, interception, erosion, drainage and leaching. From the maps of yearly use and the emission factors, emissions to surface water are calculated as the sum of drift, direct losses, erosion and drainage. The calculated substance emission is compared to measured concentration in surface water for a number of selected upstream areas with homogeneous clusters of crops (and therefore substance use). Calculated emissions

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

    PubMed

    Williams, Mark R; Buda, Anthony R; Elliott, Herschel A; Collick, Amy S; Dell, Curtis; Kleinman, Peter J A

    2015-05-01

    Riparian seepage zones in headwater agricultural watersheds represent important sources of nitrate-nitrogen (NO-N) to surface waters, often connecting N-rich groundwater systems to streams. In this study, we examined how NO-N concentrations in seep and stream water were affected by NO-N processing along seep surface flow paths and by upslope applications of N from fertilizers and manures. The research was conducted in two headwater agricultural watersheds, FD36 (40 ha) and RS (45 ha), which are fed, in part, by a shallow fractured aquifer system possessing high (3-16 mg L) NO-N concentrations. Data from in-seep monitoring showed that NO-N concentrations generally decreased downseep (top to bottom), indicating that most seeps retained or removed a fraction of delivered NO-N (16% in FD36 and 1% in RS). Annual mean N applications in upslope fields (as determined by yearly farmer surveys) were highly correlated with seep NO-N concentrations in both watersheds (slope: 0.06; = 0.79; < 0.001). Strong positive relationships also existed between seep and stream NO-N concentrations in FD36 (slope: 1.01; = 0.79; < 0.001) and in RS (slope: 0.64; = 0.80; < 0.001), further indicating that N applications control NO-N concentrations at the watershed scale. Our findings clearly point to NO-N leaching from upslope agricultural fields as the primary driver of NO-N losses from seeps to streams in these watersheds and therefore suggest that appropriate management strategies (cover crops, limiting fall/winter nutrient applications, decision support tools) be targeted in these zones. PMID:26024271

  18. Risk-Cost-Benefit Analysis Of Atrazine In Drinking Water From Agricultural Activities

    NASA Astrophysics Data System (ADS)

    Aklilu, T. A.; Jagath, K. J.; Arthur, C. J.

    2004-12-01

    This study provides a new methodology for investigating the trade-offs between the health risks and economic benefits of using atrazine in the agricultural sector and a more holistic insight to pesticide management issues. Regression models are developed to predict the stream atrazine concentrations and finished water atrazine concentration at high-risk community water supplies in the US using surface water. The predicted finished water atrazine concentrations are then used in health risk assessment. The computed health risks are compared with the total surplus in the US corn market for different atrazine application rates using the demand and supply functions developed in this work. Analysis of different scenarios with consumer price premiums (preferences) for chemical-free to reduced chemical corn provided interesting results on the potential for future pesticide and land use management. This is an interdisciplinary work that has attempted to integrate and consider the interaction between weed sciences, economics, water quality, human health risk and human reaction to changes in different pesticide use scenarios. The results showed that this methodology provides a scientific framework for future decision-making and policy evaluation in pesticide management, especially when better regional and national data are available.

  19. Water movement within the unsaturated zone in four agricultural areas of the United States

    USGS Publications Warehouse

    Fisher, L.H.; Healy, R.W.

    2008-01-01

    Millions of tons of agricultural fertilizer and pesticides are applied annually in the USA. Due to the potential for these chemicals to migrate to groundwater, a study was conducted in 2004 using field data to calculate water budgets, rates of groundwater recharge and times of water travel through the unsaturated zone and to identify factors that influence these phenomena. Precipitation was the only water input at sites in Indiana and Maryland; irrigation accounted for about 80% of total water input at sites in California and Washington. Recharge at the Indiana site (47.5 cm) and at the Maryland site (31.5 cm) were equivalent to 51 and 32%, respectively, of annual precipitation and occurred between growing seasons. Recharge at the California site (42.3 cm) and Washington site (11.9 cm) occurred in response to irrigation events and was about 29 and 13% of total water input, respectively. Average residence time of water in the unsaturated zone, calculated using a piston-flow approach, ranged from less than 1 yr at the Indiana site to more than 8 yr at the Washington site. Results of bromide tracer tests indicate that at three of the four sites, a fraction of the water applied at land surface may have traveled to the water table in less than 1 yr. The timing and intensity of precipitation and irrigation were the dominant factors controlling recharge, suggesting that the time of the year at which chemicals are applied may be important for chemical transport through the unsaturated zone. Copyright ?? 2008 by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America. All rights reserved.

  20. Residential water consumption, motivation for conserving water and the continuing tragedy of the commons.

    PubMed

    Corral-Verdugo, Victor; Frías-Armenta, Martha; Pérez-Urias, Faviola; Orduña-Cabrera, Virginia; Espinoza-Gallego, Noelia

    2002-10-01

    This paper explores the effect of the perception of externalities (PE) on residential water consumption. Externalities occur when individuals make decisions that harm others, without concern for the impact or feeling a need to compensate for the harm. The aim of this study was to investigate whether PE affects people's motivation to conserve water, and, consequently, the practice of residential water consumption. Two hundred eighty Mexican citizens responded to a questionnaire investigating how they perceived that other individuals in their community wasted water. Respondents were also asked about their motives to conserve water, and direct observations of individual water consumption were recorded. Results were processed within a structural equations model, which revealed that motives to conserve water significantly inhibit water consumption. Since the perception of extemalities also inhibits conservation motives, the resulting effect of PE on water consumption is positive. This result means that the more people perceive that others waste water, the less their conservation motives, and, therefore, the more their own water consumption.

  1. Water hyacinths as a resource in agriculture and energy production: a literature review.

    PubMed

    Gunnarsson, Carina C; Petersen, Cecilia Mattsson

    2007-01-01

    Water hyacinths are becoming a problem in lakes, ponds and waterways in many parts of the world. This paper contains a literature study of different ways to use water hyacinths, mainly in agricultural or alternative energy systems. The literature review indicated that water hyacinths can be rich in nitrogen, up to 3.2% of DM and have a C/N ratio around 15. The water hyacinth can be used as a substrate for compost or biogas production. The sludge from the biogas process contains almost all of the nutrients of the substrate and can be used as a fertiliser. The use of water hyacinth compost on different crops has resulted in improved yields. The high protein content makes the water hyacinth possible to use as fodder for cows, goats, sheep and chickens. Water hyacinth, due to its abundant growth and high concentrations of nutrients, has a great potential as fertiliser for the nutrient deficient soils of Africa and as feed for livestock. Applying the water hyacinths directly without any other processing than sun drying, seems to be the best alternative in small-scale use due to the relatively small losses of nutrients and workload required. To meet the ever-growing energy demand, biogas production could be one option but it requires investments and technological skills that would impose great problems in developing countries where the water hyacinth is often found. Composting as an alternative treatment has the advantage of a product that is easy to work into the soil compared with dried water hyacinths, because of the decomposed structure. Harvesting and transport of water hyacinths can be conducted manually on a small scale and does not require a new harvesting technique to be introduced. Transporting of fresh water hyacinths means, if used as fertiliser in amounts large enough to enhance or effect crop growth, an unreasonably large labour requirement. Based on the labour need and the limited access to technology, using dried water hyacinths, as green manure is a

  2. Water hyacinths as a resource in agriculture and energy production: a literature review.

    PubMed

    Gunnarsson, Carina C; Petersen, Cecilia Mattsson

    2007-01-01

    Water hyacinths are becoming a problem in lakes, ponds and waterways in many parts of the world. This paper contains a literature study of different ways to use water hyacinths, mainly in agricultural or alternative energy systems. The literature review indicated that water hyacinths can be rich in nitrogen, up to 3.2% of DM and have a C/N ratio around 15. The water hyacinth can be used as a substrate for compost or biogas production. The sludge from the biogas process contains almost all of the nutrients of the substrate and can be used as a fertiliser. The use of water hyacinth compost on different crops has resulted in improved yields. The high protein content makes the water hyacinth possible to use as fodder for cows, goats, sheep and chickens. Water hyacinth, due to its abundant growth and high concentrations of nutrients, has a great potential as fertiliser for the nutrient deficient soils of Africa and as feed for livestock. Applying the water hyacinths directly without any other processing than sun drying, seems to be the best alternative in small-scale use due to the relatively small losses of nutrients and workload required. To meet the ever-growing energy demand, biogas production could be one option but it requires investments and technological skills that would impose great problems in developing countries where the water hyacinth is often found. Composting as an alternative treatment has the advantage of a product that is easy to work into the soil compared with dried water hyacinths, because of the decomposed structure. Harvesting and transport of water hyacinths can be conducted manually on a small scale and does not require a new harvesting technique to be introduced. Transporting of fresh water hyacinths means, if used as fertiliser in amounts large enough to enhance or effect crop growth, an unreasonably large labour requirement. Based on the labour need and the limited access to technology, using dried water hyacinths, as green manure is a

  3. 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.

  4. Hydrologic and water-quality impacts of agricultural land use changes incurred from bioenergy policies

    NASA Astrophysics Data System (ADS)

    Lin, Zhulu; Anar, Mohammad J.; Zheng, Haochi

    2015-06-01

    The US Energy Independence and Security Act (EISA) of 2007 has contributed to widespread changes in agricultural land uses. The impact of these land use changes on regional water resources could also be significant. Agricultural land use changes were evaluated for the Red River of the North Basin, an international river basin shared by the US and Canada. The influence of the land use change on spring snowmelt flooding and downstream water quality was also assessed using watershed modeling. The planting areas for corn and soybean in the basin increased by 62% and 18%, while those for spring wheat, forest, and pasture decreased by 30%, 18%, and 50%, from 2006 to 2013. Although the magnitude of spring snowmelt peak flows in the Red River did not change from pre-EISA to post-EISA, our uncertainty analysis of the normalized hydrographs revealed that the downstream streamflows had a greater variability under the post-EISA land use scenario, which may lead to greater uncertainty in predicting spring snowmelt floods in the Red River. Hydrological simulation also showed that the sediment and nutrient loads at the basin's outlet in the US and Canada border increased under the post-EISA land use scenario, on average sediment increasing by 2.6%, TP by 14.1%, nitrate nitrogen by 5.9%, and TN by 9.1%.

  5. 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.

  6. 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

  7. 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

  8. U.S. Biofuel Policies and Domestic Shifts in Agricultural Land Use and Water Balances

    NASA Astrophysics Data System (ADS)

    Teter, J.; Yeh, S.; Mishra, G. S.

    2014-12-01

    Policies promoting domestic biofuels production could lead to significant changes in cropping patterns. Types of direct and indirect land use change include: switching among crops (displacement), expanding cropped area (extensification), and altering water/soil management practices (e.g. irrigation, tillage) (intensification). Most studies of biofuels water use impacts calculate the water intensity of biofuels in liters of irrigated/total evapotranspired water per unit energy of biofuels. But estimates based on this approach are sensitive to assumptions (e.g. co-product allocation, system boundaries), and do not convey policy-relevant information, as highlighted by the issue of land use change. We address these shortcomings by adopting a scenario-based approach that combines economic modeling with crop-water modeling of major crops and biofuel feedstocks. This allows us to holistically compare differences in water balances across policy scenarios in an integrated economic/agricultural system. We compare high spatial resolution water balance estimates under three hypothetical policy scenarios: 1) a counterfactual no-policy scenario, 2) modified Renewable Fuels Standard mandates (M-RFS2), & 3) a national Low Carbon Fuel Standard plus a modified RFS2 scenario (LCFS+RFS2). Differences between scenarios in crop water balances (i.e. transpiration, evaporation, runoff, groundwater infiltration, & irrigation) are regional and are a function of changes in land use patterns (i.e. displacement, intensification, & extensification), plus variation in crop water-use characteristics. Cropped land area increases 6.2% and 1.6% under M-RFS2 and LCFS+RFS2 scenarios, respectively, by 2030. Both policy scenarios lead to reductions in net irrigation volumes nationally compared to the no-policy scenario, though more irrigation occurs in regions of the Midwest and West. The LCFS+RFS2 reduces net irrigation water use by 3.5 times more than M-RFS2. However, both policies drive

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

    USGS Publications Warehouse

    Maurer, D.K.; Johnson, A.K.; Welch, A.H.

    1994-01-01

    Implementation of Operating Criteria and Procedures for Newlands Project irrigation and Public Law 101-618 could result in significant reductions of surface water used for agriculture in the Carson Desert, Nevada and thereby could affect recharge through the aquifer system and local groundwater supply. This report summarizes previous studies on how the aquifers are recharged and what controls groundwater flow and quality. A near-surface saturated zone could exist at the top of the shallow aquifer near the central and eastern parts of the basin, where underlying clay beds impede vertical flow. In the basalt aquifer, water levels have declined about 10 ft 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, inter- mediate, and basalt aquifers. Installing impermeable lining in canals and removing adjacent land from production could cause water-level declines more than 10 ft in the shallow aquifer as far as 2 mi from lined canals. Reducing recharge to the shallow aquifer by 25,000-50,000 acre-ft/yr beneath 30,000 acres could cause water levels to decline from 4 to 17 ft, depending on the distri- bution of specific yield in the basin. Where water is pumped from a near-surface zone of the shallow aquifer, lower water levels might not greatly affect pumping wells where the zone is thickest, but could cause wells to go dry where the zone is thin.

  10. Evaluating multiple indices of agricultural water use efficiency and productivity to improve comparisons between sites and trends

    NASA Astrophysics Data System (ADS)

    Levy, M. C.

    2012-12-01

    Approximately 70% of global available freshwater supplies are used in the agricultural sector. Increased demands for water to meet growing population food requirements, and expected changes in the reliability of freshwater supplies due to climate change, threaten the sustainability of water supplies worldwide - not only on farms, but in connected cities and industries. Researchers concerned with agricultural water use sustainability use a variety of theoretical and empirical measures of efficiency and productivity to gain insight into the sustainability of agricultural water use. However, definitions of measures, or indices, vary between different natural and political boundaries, across regions, states and nations and between their respective research, industry, and environmental groups. Index development responds to local data availability and local agendas, and there is debate about the validity of various indices. However, real differences in empirical index measures are not well-understood across the multiple disciplines that study agricultural water use, including engineering and hydrology, agronomy, climate and soil sciences, and economics. Nevertheless reliable, accessible, and generalizable indices are required for planners and policymakers to promote sustainable water use systems. This study synthesizes a set of water use efficiency and productivity indices based on academic, industry and government literature in California and Australia, two locations with similarly water-stressed and valuable agricultural industries under pressure to achieve optimal water use efficiency and productivity. Empirical data at the irrigation district level from the California San Joaquin Valley and Murray Darling Basin states of Victoria and New South Wales in Australia are used to compute indices that estimate efficiency, yield productivity, and economic productivity of agricultural water use. Multiple index estimates of same time-series data demonstrate historical spread

  11. Spatial probability of soil water repellency in an abandoned agricultural field in Lithuania

    NASA Astrophysics Data System (ADS)

    Pereira, Paulo; Misiūnė, Ieva

    2015-04-01

    Water repellency is a natural soil property with implications on infiltration, erosion and plant growth. It depends on soil texture, type and amount of organic matter, fungi, microorganisms, and vegetation cover (Doerr et al., 2000). Human activities as agriculture can have implications on soil water repellency (SWR) due tillage and addition of organic compounds and fertilizers (Blanco-Canqui and Lal, 2009; Gonzalez-Penaloza et al., 2012). It is also assumed that SWR has a high small-scale variability (Doerr et al., 2000). The aim of this work is to study the spatial probability of SWR in an abandoned field testing several geostatistical methods, Organic Kriging (OK), Simple Kriging (SK), Indicator Kriging (IK), Probability Kriging (PK) and Disjunctive Kriging (DK). The study area it is located near Vilnius urban area at (54 49' N, 25 22', 104 masl) in Lithuania (Pereira and Oliva, 2013). It was designed a experimental plot with 21 m2 (07x03 m). Inside this area it was measured SWR was measured every 50 cm using the water drop penetration time (WDPT) (Wessel, 1998). A total of 105 points were measured. The probability of SWR was classified in 0 (No probability) to 1 (High probability). The methods accuracy was assessed with the cross validation method. The best interpolation method was the one with the lowest Root Mean Square Error (RMSE). The results showed that the most accurate probability method was SK (RMSE=0.436), followed by DK (RMSE=0.437), IK (RMSE=0.448), PK (RMSE=0.452) and OK (RMSE=0.537). Significant differences were identified among probability tests (Kruskal-Wallis test =199.7597 p<0.001). On average the probability of SWR was high with the OK (0.58±0.08) followed by PK (0.49±0.18), SK (0.32±0.16), DK (0.32±0.15) and IK (0.31±0.16). The most accurate probability methods predicted a lower probability of SWR in the studied plot. The spatial distribution of SWR was different according to the tested technique. Simple Kriging, DK, IK and PK methods

  12. On-line systems for continuous water and gas isotope ratio measurements.

    PubMed

    Huber, Christof; Leuenberger, Markus

    2005-09-01

    New continuous on-line techniques for water and air extracted from ice cores are developed. Water isotope ratio determination on any of the water phases (water vapour, water, ice) is of great relevance in different research fields, such as climate and paleoclimate studies, geological surveys, and hydrological studies. The conventional techniques for water isotopes are available in different layouts but all of them are rather time-consuming. Here we report new fast on-line techniques that process water as well as ice samples. The analysis time is only approximately 5 min per sample which includes equilibration and processing. Measurement precision and accuracy are better than 0.1 per thousand and 1 per thousand for delta18O and deltaD, respectively, comparable to conventional techniques. The new on-line techniques are able to analyze a wide range of aqueous samples. This allows, for the first time, to make continuous isotope measurements on ice cores. Similarly, continuous and fast analysis of aqueous samples can be of great value for hydrological, geological and perhaps medical applications.Furthermore, a new technique for the on-line analysis of air isotopes extracted from ice cores is developed. This technique allows rapid analyses with high resolution of the main air components nitrogen, oxygen, and argon. Measurement precision is comparable to precisions obtained by conventional techniques. It is now possible to measure delta15N and delta18O(atm) over entire ice cores helping to synchronize chronologies, to assess gas age-ice age differences, and to calibrate the paleothermometry for rapid temperature changes. This new on-line air extraction and analyzing technique complements the water methods in an ideal way as it separates the air from the melt-water of an ice sample. The remaining water waste flux can directly be analyzed by the water methods.

  13. Field test results for nitrogen removal by the constructed wetland component of an agricultural water recycling system

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wetland Reservoir Subirrigation Systems (WRSIS) are innovative agricultural water recycling systems that can provide economic and environmental benefits. A constructed wetland is a main component of WRSIS, and an important function of this constructed wetland is drainage water treatment of nitrog...

  14. Reuse/disposal of agricultural drainage water with high levels of salinity and toxic trace elements in central California.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agricultural drainage waters in the western San Joaquin Valley of Central California contain high levels of salts, boron (B) and selenium (Se). Discharge of the drainage water directly into the Kesterson Reservoir in 1980's was hazardous to plants and wildlife. To investigate the plausibility of usi...

  15. Hydrologic and biogeochemical controls of river subsurface solutes under agriculturally enhanced ground water flow

    USGS Publications Warehouse

    Wildman, R.A.; Domagalski, J.L.; Hering, J.G.

    2009-01-01

    The relative influences of hydrologic processes and biogeochemistry on the transport and retention of minor solutes were compared in the riverbed of the lower Merced River (California, USA). The subsurface of this reach receives ground water discharge and surface water infiltration due to an altered hydraulic setting resulting from agricultural irrigation. Filtered ground water samples were collected from 30 drive point locations in March, June, and October 2004. Hydrologic processes, described previously, were verified by observations of bromine concentrations; manganese was used to indicate redox conditions. The separate responses of the minor solutes strontium, barium, uranium, and phosphorus to these influences were examined. Correlation and principal component analyses indicate that hydrologic processes dominate the distribution of trace elements in the ground water. Redox conditions appear to be independent of hydrologic processes and account for most of the remaining data variability. With some variability, major processes are consistent in two sampling transects separated by 100 m. Copyright ?? 2009 by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America. All rights reserved.

  16. Crop Insurance Increases Water Withdrawals for Irrigation in Agriculture

    NASA Astrophysics Data System (ADS)

    Konar, M.; Deryugina, T.; Lin, X.

    2015-12-01

    Agricultural production remains particularly vulnerable to weather fluctuations and extreme events, such as droughts, floods, and heat waves. Crop insurance is a risk management tool that has been developed to mitigate some of this weather risk and protect farmer income in times of poor production. However, it is not clear what the implications of crop insurance are for crop irrigation. By providing a guaranteed level of income in case of crop failure, crop insurance can reduce the farmer's incentive to irrigate. Thus, crop insurance can decrease water use in times of drought and promote water sustainability. However, to minimize this "moral hazard", the insurer may requir