HR: 0800h
AN: H31B-1301    [Abstracts]
TI: Laboratory, field, and modeling studies of organophosphate pesticide fate and transport during simulated rainfall-runoff events
AU: * Coelho, C J
EM: ccoelho1@mail.csuchico.edu
AF: California State University, Chico, 400 West First Street, Chico, CA 95929 United States
AU: Brown, D L
EM: dlbrown@csuchico.edu
AF: California State University, Chico, 400 West First Street, Chico, CA 95929 United States
AU: Johns, M
EM: mjohns@csuchico.edu
AF: California State University, Chico, 400 West First Street, Chico, CA 95929 United States
AU: Lopez, R
EM: www.countyofglenn.net
AF: Glenn County Agricultural Department, 720 N. Colusa St., Willows, CA 95988 United States
AB: Agricultural runoff is a major source of water pollution in California. Best Management Practices (BMPs) can be used by farmers to reduce pesticides loading to surface waters. In previous studies, it has been found that the organophosphate pesticide diazinon has an affinity for sorption on carbon sources. This study used rice straw compost as a BMP to increase carbon content of orchard soils and to investigate the sorption capability of the compost. Laboratory isotherm experiments were conducted to determine the sorption capacity and equilibrium coefficients of the compost and soil. Using the Kd values of the compost and soil as well as infiltration data from previous studies, a model was created to determine the sorption capability of the compost in the field. Field experiments are in progress using a rainfall simulation system, with five controlled and five compost sites all sprayed with diazinon. Results from the field trials will be compared with the model. Preliminary results have shown that the sorption capacity of the compost could significantly reduce organophosphate pesticide runoff into water ways
DE: 1834 Human impacts
DE: 1838 Infiltration
DE: 1865 Soils (0486)
DE: 1871 Surface water quality
DE: 1880 Water management (6334)
SC: Hydrology [H]
MN: Fall Meeting 2005