Submitted to: ASA-CSSA-SSSA Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 10/1/2004
Publication Date: 10/31/2004
Citation: Smith, D.R., Warnemuende, E.A., Owens, P.R. 2004. Impact of time to first runoff event on nutrient runoff and greenhouse gas emissions from manure applications. In: ASA-CSSA-SSSA Proceedings, October 31-November 4, 2004, Seattle, Washington. 2004 CDROM.
Technical Abstract: The phosphorus index in most states weights the timing manure applications as a relative function of the risk for runoff events. While studies have shown a logarithmic decay function adequately describes the nutrient losses from manure applied to fields, little is known about the impact of time to first rainfall event on greenhouse gas emissions. This study was conducted using poultry litter, swine manure and inorganic fertilizers applied at iso-phosphoric levels. Rainfall events occurred at 1, 4, 8, 15 and 29 days after manure application. Inorganic fertilizer and swine manure produced phosphorus concentrations greater than poultry litter or unfertilized plots. While reductions in nutrient concentrations were noted between event on day 1 and 4, at day 15, phosphorus runoff were as high as those noted on day 1. Initial CO2, CH4 and N2O production was highest from the swine manure treatments. Pre-rain gas production tended to decrease with time, however, post-rain gas production increased with time to first runoff event. This study also provides information on greenhouse gas production following manure applications. [GRACEnet Publication]