| Title: | Modeling sediment and nitrogen export from a rural watershed in eastern Canada using the Soil and Water Assessment Tool |
| Authors: | Ahmad, H.M.N., A. Sinclair, R. Jamieson, A. Madani, D. Hebb, P. Havard and E.K. Yiridoe |
| Year: | 2011 |
| Journal: | Journal of Environmental Quality |
| Volume (Issue): | 40(4) |
| Pages: | 1182-1194 |
| Article ID: | |
| DOI: | 10.2134/jeq2010.0530 |
| URL (non-DOI journals): | |
| Model: | SWAT |
| Broad Application Category: | hydrologic and pollutant |
| Primary Application Category: | pollutant cycling/loss and transport |
| Secondary Application Category: | calibration, sensitivity, and/or uncertainty analysis |
| Watershed Description: | 7.84 km^2 Thomas Brook in Nova Scotia in eastern Canada |
| Calibration Summary: | |
| Validation Summary: | |
| General Comments: | |
| Abstract: | Watershed simulation models can be used to assess agricultural
nonpoint-source pollution and for environmental planning
and improvement projects. However, before application of
any process-based watershed model, the model performance
and reliability must be tested with measured data. Th e Soil
and Water Assessment Tool version 2005 (SWAT2005) was
used to model sediment and nitrogen loads from the Thomas
Brook Watershed, which drains a 7.84 km^2 rural landscape in
the Annapolis Valley of Nova Scotia, Canada. The Thomas
Brook SWAT model was comprised of 28 subbasins and 265
hydrologic response units, most of them containing agricultural
land use, which is the main nonpoint nitrogen source in the
watershed. Crop rotation schedules were incorporated into the
model using field data collected within Agriculture and Agri-
Food Canada’s Watershed Evaluation of Beneficial Management
Practices program. Model calibration (2004–2006) and
validation (2007–2008) were performed on a monthly basis
using continuous stream fl ow, sediment, and nitrogen export
measurements. Model performance was evaluated using the
coefficient of determination, Nash-Sutcliff efficiency (NSE),
and percent bias (PBIAS) statistics. Study results show that
the model performance was satisfactory (NSE > 0.4; R2 > 0.5)
for stream fl ow, sediment, nitrate-nitrogen, and total nitrogen
simulations. Annual corn, barley, and wheat yields were also
simulated well, with PBIAS values ranging from 0.3 to 7.2%.
Th is evaluation of SWAT demonstrated that the model has the
potential to be used as a decision support tool for agricultural
watershed management in Nova Scotia. |
| Language: | English |
| Keywords: | |