RESEARCH AND MODIFY RZWQM2 MODEL FOR SIMULATING PESTICIDE TRANSPORT AND FATE IN SURFACE WATER FROM CALIFORNIA AGRICULTURAL FIELDS
Agricultural Systems Research Unit
2013 Annual Report
1a.Objectives (from AD-416):
The primary goal is to customize and improve the current Root Zone Water Quality Model (RZWQM2) performance under California conditions to simulate soil erosion and other features related to pesticide risk assessment.
1b.Approach (from AD-416):
The research will be conducted with a team effort between USDA and UC DAVIS as well as the scientists from the California Department of Pesticide Regulations. Specific tasks are as follows:
(a) To simulate soil erosion and transport in agricultural fields;
(b) To simulate pesticide transport and fate associated with runoff water and
sediment, generated by rainfall and various types of irrigation;
(c) To generate time series output of simulated runoff flow, pesticide
concentration, plant growth and crop evapotranspiration rate (ET);
(d) To test the quickTree, quickPlant and DSSAT models for trees and vegetable
The GLEAMS erosion model was linked to the ARS Root Zone Water Quality model, for estimating the pesticide transport to runoff. This linkage was initially tested with some experimental data from California and Colorado. Sensitivity of the soil parameters for infiltration, runoff, soil erosion and pesticides in runoff was evaluated and the most sensitive parameters identified. The erosion component is being further improved. The final product will improve pesticide transport with sediments in runoff.