Project Number: 6612-61660-001-26
Project Type: Reimbursable

Start Date: Aug 01, 2007
End Date: Jun 30, 2010

Objective:
Evaluate the effect of runoff occurring at different times after application of broiler litter and under different environmental conditions on the concentration of estradiol, estrone, and testosterone in surface runoff.

Approach:
The study will be conducted at the University of Georgia Central Research and Education Center, near Eatonton, GA. Rainfall simulation will be conducted in winter and summer each year on sixteen 1.5 x 2 m plots established on Altavista sandy loam. Runoff from the rain simulation will be collected at the downslope end of each plot. Broiler litter will be applied to all plots at 5 Mg ha-1 prior to simulation following which four rainfall simulation treatments will be imposed. These will consist of rainfall simulation at 0 (immediately after litter application), 1, 2, and 4 weeks after litter application, with four replications for each treatment. Simulated rainfall will be applied at 50 mm h-1 and all runoff will be collected for 30 min after runoff starts. Subsamples from the collected runoff of each plot will be analyzed for estradiol, estrone, and testosterone concentrations at the Agricultural and Environmental Service Laboratory University of Georgia in Athens and Laboratories of the Crop and Soil Sciences Department, UGA, located in Athens and Griffin. To prevent natural rainfall from reaching the plots, a transparent cover will be placed on each plot during the 4 weeks of the study. This cover will be mounted on 40-cm legs so that air will be able circulate below the cover to prevent excessive heat buildup. Soil temperature (0-10 cm) and soil water content will be monitored and recorded with dataloggers during the study period.