| Title: | Using the Soil and Water Assessment Tool to estimate achievable water quality targets through implementation of beneficial management practices in an agricultural watershed |
| Authors: | Yang, Q., F.A. Benoy, T.L. Chow, L.-L. Daigle, C.P.-A. Bourque and F.-R. Meng |
| Year: | 2012 |
| Journal: | Journal of Environmental Quality |
| Volume (Issue): | 41(1) |
| Pages: | 64-72 |
| Article ID: | |
| DOI: | 10.2134/jeq2010.0250 |
| URL (non-DOI journals): | |
| Model: | SWAT |
| Broad Application Category: | pollutant only |
| Primary Application Category: | BMP and/or cropping system assessment |
| Secondary Application Category: | pollutant cycling/loss and transport |
| Watershed Description: | 14.5 km^2 Black Brook in northwestern New Brunswick, Canada |
| Calibration Summary: | |
| Validation Summary: | |
| General Comments: | |
| Abstract: | Runoff from crop production in agricultural watersheds can
cause widespread soil loss and degradation of surface water
quality. Beneficial management practices (BMPs) for soil
conservation are often implemented as remedial measures
because BMPs can reduce soil erosion and improve water
quality. However, the efficacy of BMPs may be unknown
because it can be affected by many factors, such as farming
practices, land-use, soil type, topography, and climatic
conditions. As such, it is difficult to estimate the impacts of
BMPs on water quality through field experiments alone.
In this research, the Soil and Water Assessment Tool was
used to estimate achievable performance targets of water
quality indicators (sediment and soluble P loadings) after
implementation of combinations of selected BMPs in the Black
Brook Watershed in northwestern New Brunswick, Canada.
Four commonly used BMPs (flow diversion terraces [FDTs],
fertilizer reductions, tillage methods, and crop rotations), were
considered individually and in different combinations. At the
watershed level, the best achievable sediment loading was 1.9
t ha-1 yr-1 (89% reduction compared with default scenario),
with a BMP combination of crop rotation, FDT, and no-till.
The best achievable soluble P loading was 0.5 kg ha-1 yr-1
(62% reduction), with a BMP combination of crop rotation
and FDT and fertilizer reduction. Targets estimated through
nonpoint source water quality modeling can be used to evaluate
BMP implementation initiatives and provide milestones for the
rehabilitation of streams and rivers in agricultural regions. |
| Language: | English |
| Keywords: | |