| Title: | An improved representation of vegetative filter strips in SWAT |
| Authors: | Cibin, R., I. Chaubey, M. Helmers, K.P. Sudheer, M.J. White and J.G. Arnold |
| Year: | 2018 |
| Journal: | Transactions of the ASABE |
| Volume (Issue): | 61(3) |
| Pages: | 1017-1024 |
| Article ID: | |
| DOI: | 10.13031/trans.12661 |
| URL (non-DOI journals): | |
| Model: | SWAT (modified) |
| Broad Application Category: | hydrologic and pollutant |
| Primary Application Category: | BMP and/or cropping system assessment |
| Secondary Application Category: | model and/or data comparison |
| Watershed Description: | Three plots of paired drainage areas, ranging in size from 0.5 to 32 ha, located in central Iowa, U.S. |
| Calibration Summary: | |
| Validation Summary: | |
| General Comments: | |
| Abstract: | Vegetative filter strips (VFS) are popular conservation practices installed at the edges of agricultural fields to
reduce losses of pollutants from agricultural areas to receiving waterbodies. The recent interest in using VFS areas as
multifunctional landscapes necessitates an improved depiction of VFS in simulation models. This study is aimed to enhance
the physical representation of VFS in the Soil and Water Assessment Tool (SWAT) to improve the representation of ecohydrologic
processes and land management practices in VFS areas. The proposed enhancement enables routing of water,
sediment, and nutrients from the source area through the VFS area and makes the infiltrated water and nutrients available
for filter crop uptake. The improvements are implemented in SWAT by modifying input files through Matlab scripts and by
changing SWAT subroutines to enable routing. The model improvements are tested with three paired watershed studies with
and without edge-of-field VFS in central Iowa. The improved model estimated 46% runoff reduction, 91% sediment reduction,
83% total phosphorus reduction, and 54% nitrate reduction with VFS, and these estimates closely matched the measured
VFS reductions. The improved model was able to represent increased infiltration, soil moisture, and denitrification in
the VFS area, along with accurately capturing crop yields in the source and VFS areas. Overall, the results indicate improved
physical representation of VFS in SWAT. |
| Language: | English |
| Keywords: | Conservation measures, Flexible buffer strips, Multifunctional buffers, SWAT model, Vegetative filter strips. |