SWAT Literature Database for Peer-Reviewed Journal Articles

Title:Effectiveness of Vegetative Filter Strips in Reducing Pesticide Loading: Quantifying Pesticide Trapping Efficiency 
Authors:Sabbagh, G.J., G.A. Fox, A Kamanzi, B. Roepke and J.-Z. Tang 
Journal:Journal of Environmental Quality 
Article ID: 
URL (non-DOI journals): 
Broad Application Category:pollutant only 
Primary Application Category:BMP assessment 
Secondary Application Category:pesticide fate and transport 
Watershed Description:five filter strip studies previously published 
Calibration Summary: 
Validation Summary: 
General Comments:It appears that the authors did not actually run SWAT but rather simply used the FILTERW equation in the model. 
Abstract:Pesticide trapping efficiency of vegetated filter strips (VFS) is commonly predicted with low success using empirical equations based solely on physical characteristics such as width and slope. The objective of this research was to develop and evaluate an empirical model with a foundation of VFS hydrological, sedimentological, and chemical specific parameters. The literature was reviewed to pool data from five studies with hypothesized significant parameters: pesticide and soil properties, percent reduction in runoff volume (i.e., infiltration) and sedimentation, and filter strip width. The empirical model was constructed using a phase distribution parameter, defined as the ratio of pesticide mass in dissolved form to pesticide mass sorbed to sediment, along with the percent infiltration, percent sedimentation, and the percent clay content (R2 = 0.86 and standard deviation of differences [STDD] of 7.8%). Filter strip width was not a statistically significant parameter in the empirical model. For low to moderately sorbing pesticides, the phase distribution factor became statistically insignificant; for highly sorbing pesticides, the phase distribution factor became the most statistically significant parameter. For independent model evaluation datasets, the empirical model based on infiltration and sediment reduction, the phase distribution factor, and the percent clay content (STDD of 14.5%) outperformed existing filter strip width equations (STDD of 38.7%). This research proposed a procedure linking a VFS hydrologic simulation model with the proposed empirical trapping efficiency equation. For datasets with sufficient information for the VFS modeling, the linked numerical and empirical models significantly (R2 = 0.74) improved predictions of pesticide trapping over empirical equations based solely on physical VFS characteristics.