SWAT Literature Database for Peer-Reviewed Journal Articles

Title:Assessment of the environmental fate of the herbicides Flufenacet and Metazachlor with the SWAT model 
Authors:Fohrer, N., A. Dietrich, O. Kolychalow and U. Ulrich 
Journal:Journal of Environmental Quality 
Article ID: 
URL (non-DOI journals): 
Broad Application Category:hydrologic & pollutant 
Primary Application Category:pesticide fate and transport 
Secondary Application Category:hydrologic assessment 
Watershed Description:50 km^2 Kielstau located in the state of Schleswig Holstein in northern Germany 
Calibration Summary: 
Validation Summary: 
General Comments:This paper is part of a JEQ special SWAT section. 
Abstract:This study aims to assess the environmental fate of the herbicides Flufenacet and Metazachlor in the Northern German Lowlands with the ecohydrological Soil and Water Assessment Tool (SWAT model) and to test the sensitivity of pesticide related input parameters on the modeled transport dynamics. The river discharge of the Kielstau watershed was calibrated (NSE: 0.83, r²= 0.84) and validated (NSE: 0.76, r²= 0.77) for a daily time step. The environmental fate of the two commonly used herbicides Metazachlor (NSE: 0.68, r²= 0.62) and Flufenacet (NSE: 0.13, r²= 0.51) was simulated adequately. In comparison to Metazachlor the simulated Flufenacet concentration and loads show a lower model efficiency due to the weaker simulation of the stream flow. The in-stream herbicide loads were less than 0.01 % of the applied amount in the observed time period and thus not in conflict with European Environmental Legislation. The sensitivity analysis showed that besides the accurate simulation of stream flow the parameterization of the temporal and spatial distribution of the herbicide application throughout the watershed is the key factor for appropriate modeling results, whereas the physico-chemical properties of the pesticides play a minor role in the modeling process.