SWAT Literature Database for Peer-Reviewed Journal Articles

Title:Water quality model output uncertainty as affected by spatial resolution of input data 
Authors:Cotter, A.S., I. Chaubey, T.A. Costello, T.S. Soerens, and M.A. Nelson 
Journal:Journal of the American Water Resources Association 
Article ID: 
URL (non-DOI journals): 
Broad Application Category:hydrologic & pollutant 
Primary Application Category:input effects 
Secondary Application Category:pollutant cycling/loss and transport 
Watershed Description:1890 ha Moores Creek (northwest Arkansas) 
Calibration Summary:Monthly (1997-98) E values: flow = .76 sediment = .48 nitrate = .44 total P = .66 
Validation Summary:Average annual relative errors reported, relative to 30x30 m DEM 
General Comments:DEM, land use, & soil data resolution were evaluated. The effects of 7 DEM resolutions (30 m up to 1000 m) were evaluated for flow, sediment, nitrate, & total P transport. Flow volumes decreased as DEM resolution became coarser and average slope also decreased from 6% at a 30 m resolution to 1.5% at a 1,000 m resolution (and slope length increased). DEM had the greatest impact of evaluated inputs. Coarser land use data resulted in high uncertainty for all output. Soil data resolution affected only sediment and total P. 
Keywords:modeling; geographic information system; SWAT model; water quality; output uncertainty