SWAT Literature Database for Peer-Reviewed Journal Articles

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 
Journal:Journal of Environmental Quality 
Volume (Issue):40(4) 
Article ID: 
URL (non-DOI journals): 
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.