Click on “Download PDF” for the PDF version or on the title for the HTML version. If you are not an ASABE member or if your employer has not arranged for access to the full-text, Click here for options. Runoff Nutrient Loads as Affected by Residue Cover, Manure Application Rate, and Flow RatePublished by the American Society of Agricultural and Biological Engineers, St. Joseph, Michigan www.asabe.org Citation: Transactions of the ASABE. 55(1): 249-258. (doi: 10.13031/2013.41252) @2012Authors: C. A. Thayer, J. E. Gilley, L. M. Durso, D. B. Marx Keywords: Beef cattle, Feedlots, Land application, Manure management, Manure runoff, Nitrogen, Nutrients, Phosphorus, Runoff, Water quality Manure is applied to cropland areas with varying surface cover to meet single-year or multiple-year crop nutrient requirements. The objectives of this field study were to: (1) examine runoff water quality characteristics following land application of manure to sites with and without wheat residue, (2) compare the water quality impacts of land application of manure to meet 0-, 1-, 2-, 4-, and 8-year P-based requirements for corn, and (3) evaluate the effects of varying runoff rates on runoff nutrient loads. Three 30-min simulated rainfall events, separated by 24 h intervals, were applied at an intensity of 70 mm h-1 to 0.75 m wide by 2.0 m long plots on which manure has been previously applied and incorporated. Runoff loads of dissolved phosphorus (DP), total phosphorus (TP), NO3-N, NH4-N, and total nitrogen (TN) were significantly greater on the plots with residue cover. Manure application rate significantly influenced runoff loads of DP, TP, NO3-N, NH4-N, and TN. No significant differences in runoff loads of DP and TP were found between sites where manure was applied to meet a 1-year or 2-year P requirement for corn. However, runoff loads of DP and TP were significantly greater on the sites where manure was applied to meet a 4-year rather than a 2-year P requirement. Each of the measured water quality parameters except electrical conductivity (EC) was significantly influenced by runoff rate. The application of manure to meet multiple-year crop nutrient requirements may increase nutrient loads in runoff. (Download PDF) (Export to EndNotes)
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