Poultry Manure and Landscape Slope Effect on E. coli Transport with Surface Runoff

MARÍA ISABEL DELGADO; CHI HOANG; HUY NGUYEN; CARL PEDERSON; RAMESH KANWAR

Lousville, Kentucky, USA

Encuentro; 2011´s ASABE´s Annual International Meeting; 2011

ASABE

Interaction between rainfall and natural landscape conditions can significantly affect the transport of nutrients and pathogens with surface runoff from manure applied fields. When rainfall occurs immediately after the application of manure, the concentration of pathogen in the runoff water could increase and affect the quality of surface water. The objective of this study was to investigate the effects of different poultry manure application rates and different field slopes on the transport of Escherichia coli (E. coli) with surface runoff. This laboratory study was conducted using a rainfall simulator and set of soil trays in the Porous Media Laboratory at Iowa State University. This experiment consisted of nine different treatments consisting of three different poultry manure application rates (0, 168 and 336 ton. ha-1) and three artificial slopes of 2, 4 and 9 %. Nine rectangular-steel trays were used for each of the four replications for each treatment, under the rainfall simulator, applying rainfall for a total period of 2.5 hours at an intensity of 25 mm. h-1. The experimental treatments used in this study reflected the real cultural practices used by farmers, within the natural landscape of central Iowa. Results of this study showed that the estimated total amount of E. coli transport with runoff water was different from slope to slope for the three slopes studied in this experiment; but the total amount of E-Coli transport was significantly higher at 9% slope in comparison to other twp slopes. An increase of 25 % of the total estimates E. coli FCU took place when manure application rate varied from 168 kg ha-1 to 336 kg ha-1.