| Title: | Impacts of input parameter spatial aggregation on an agricultural nonpoint source pollution model |
| Authors: | FitzHugh, T.W. and D.S. Mackay |
| Year: | 2000 |
| Journal: | Journal of Hydrology |
| Volume (Issue): | 236(1-2) |
| Pages: | 35-53 |
| Article ID: | |
| DOI: | 10.1016/S0022-1694(00)00276-6 |
| URL (non-DOI journals): | |
| Model: | SWAT |
| Broad Application Category: | hydrologic and pollutant |
| Primary Application Category: | HRU, subbasin, grid and/or landscape unit delineation effects |
| Secondary Application Category: | pollutant cycling/loss and transport |
| Watershed Description: | 47.8 km^2 Pheasant Branch, located in south central Wisconsin, U.S. |
| Calibration Summary: | MCOES and mean absolute errors are reported for annual and monthly streamflow comparisons; graphical streamflow & sediment comparisons also shown. |
| Validation Summary: | |
| General Comments: | Eight different watershed configurations (subwatershed/HRU combinations) were simulated in SWAT, that ranged from 3 subwatersheds & 29 HRUs to 181 subwatersheds & 1,384 HRUs. Streamflow and sediment predictions were not very sensitive to configuration changes at the watershed outlet, due to the "transport limited" nature (i.e., more sediment can be generated in the upland HRUs than can be transported throug the stream channels) of the watershed and the stable transport capacity of the lower part of the channel network. The authors also found that sediment generation in the HRUs varied by 44% between the coarsest and finest watershed configurations, even though sediment loads did not change much at the outlet (underscoring the fact that the watershed is transport-limited). Two indices denoted MAMI and MOMI were developed based on the SWAT erosion predictions that can be used to approximate the MUSLE output generated by SWAT. |
| Language: | English |
| Keywords: | Aggregation effects; Geographic information systems; Nonpoint sources; Models; Sediment transport; Sediment yield |