Recent developments in field-scale mechanistic modeling of vegetated filter strips (VFS) at effectively removing soluble and sediment-borne pesticide residues enables greater accuracy in predicting the effectiveness of different BMP's. Simulations using the PRZM-Hybrid approach, previously applied to the herbicide atrazine employing high resolution local input data, were performed with various levels of assumed VFS implementation in small MN agricultural watersheds where the insecticide chlorpyrifos is used in agronomic crops. In this approach, a small watershed is represented as a combination of unique fields, where predicted field edge runoff of water, sediment, and chemical mass from all of the fields contribute instantaneously to the daily hydrology and chemographs for the watershed. PRZM3 edge-of-field predictions for water and sediment runoff was coupled with the VFSMOD model to address performance of VFS in reducing pesticide loadings from field edge and the impact this has at large within the watershed. Required data sets, model parameterization, and model assumptions are discussed. Predicted water concentrations from small watersheds in MN, discretized and simulated as a combination of unique fields, were compared to downstream monitoring data, with model performance evaluated against the actual conditions occurring in the watersheds in the 2012 cropping year. Predicted impacts of differing levels of adoption of VFS in reducing in-stream concentrations are summarized.

PRZM-Hybrid and VFSMOD modeling of chlorpyrifos transport in small agricultural watersheds in Minnesota, USA

246th National Meeting (2013)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.