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relationships” with New York, Delaware, and West Virginia to reach out to the three additional states that have land area within the watershed. Although progress had been made in terms of nutrient and sediment reduction, the Bay’s heath did not drastically

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Agricultural runoff is a source of nutrients and sediments in surface water on the central coast of California. Treating soils with high molecular weight anionic polyacrylamide (PAM) may reduce sediments and P lost from furrow and sprinkler irrigated fields by maintaining infiltration and stabilizing soil aggregates. We conducted column and field studies to quantify the effect of PAM on infiltration rate, run off, and sediment and nutrient (ortho and total P, NO3, K) loss from cool season vegetable fields. Column studies demonstrated a reduction in infiltration for 10 soil types when PAM was continuously applied in the irrigation water at 10 ppm. Recirculating infiltrometer studies showed that in furrow systems, PAM, applied only in the initial water at 10 ppm, had no significant effect on infiltration at four of six sites evaluated. Turbidity and total suspended solids were significantly reduced in the PAM treated water. Across all sites, treatment with PAM reduced suspended solids by 85% compared to the untreated control. Additionally, soluble and total P, and total N were reduced in the PAM treated water. PAM had no effect on nitrate or salt levels in the runoff. PAM applied through sprinklers at a 5 ppm concentration was able to significantly reduce the turbidity and the suspended solids in the tailwater. Similar to the results obtained with the recirculation infiltrometer trials, PAM reduced soluble and total P and total N in the runoff, but had no significant effect on NO3-N. Total sediment loss under sprinklers was reduced by as much as 95% using PAM.

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greater protection and restoration of our natural waterways, because both human and ecological uses are currently impaired as a result of increased rates of nutrient and sediment loading. Many policies have been enacted in regions throughout the United

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grower adoption. Impairments to streams, lands, and rivers are caused by a variety of pollutants and are associated with a variety of activities, including agriculture. Eutrophication of lakes and estuaries is caused downstream of excessive sediment and

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( CDFA, 2007 ). Potential water quality concerns from agricultural production include runoff and leaching losses of nutrients, pesticides, and sediment ( Ribaudo and Johansson, 2006 ). Agriculture is considered a leading source of impairment for U

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appropriate state water agencies ( Farm Bureau of Ventura County, 2013 ). The survey included questions regarding 100 individual BMPs, which were classified into the following categories: sediment and erosion management, irrigation management, pest management

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profitability. Contaminants (such as fertilizers, agrichemicals, and sediment) leaving an operation via runoff water from an agricultural production site are considered nonpoint source pollution and can contribute to the impairment of waterways downstream

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). This is the result of EDTA's ability to extract and solubilize metals from sediments. The problem is of such concern in Europe that EDTA was subject to “priority substance for extensive evaluation” by European Union member states under European

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Using USLE standard plots, on 10% slope, on uniform Lowell silt loam soil, the influence of three soil treatments and two representative vegetable crops on soil runoff losses was determined. Yields (1990 and 1991) for each crop × soil treatment combination were also determined. Soil losses were determined by catching runoff, filtering, air drying and massing representative samples. With total volume per plot known, grams sediment per liter runoff were converted to kg/ha. Overall mean yields of pepper were 2.9, 4.7, and 3.7 and pumpkin were 47.3, 87.1 and 76.1 kg/7.3-m row, respectively. Mean sediment losses over five rainfall events in 1991 in peppers were 52, 1158, and 5362; and in pumpkins were 72, 3011, and 7271 kg/ha, for fescue, plastic and no-mulch treatments, respectively. Clearly, fescue in .6-m strips between rows, with comparable yields demonstrated (1991) and negligible sediment losses, was the best management practice (BMP).

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Abstract

The agri-business industry is faced with an unprecedented demand for its product – food. It has been estimated that the world food supply must be doubled just to feed the present population. There is little doubt that the technology exists to do this, given the inputs of water (if available), fertilizer, pesticides and increasing the area under cultivation. Many are seriously questioning whether our ecosystem can continue to tolerate the effects of intensive agriculture. These effects can include erosion, contamination of water supplies by sediment, fertilizer nutrients, pesticides and animal waste, and food processing wastes. Of course, other sectors of the economy also are over-stressing the environment, as witness the problems in the transportation, oil and electrical power industries.

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