|
|||||
|
|
Automated watershed subdivision for simulations using multi-objective optimization |
|
| Authors: | Henrique G Momm Ronald L Bingner Randall Emilaire Jurgen Garbrecht Robert R Wells Roger A Kuhnle |
| Institution: | 1. Department of Geosciences, Middle Tennessee State University, Murfreesboro, TN, USA;2. National Sedimentation Laboratory, Agricultural Research Service, United States Department of Agriculture, Oxford, MS, USA;3. Great Plains Agroclimate and Natural Resources Research Unit, Agricultural Research Service, United States Department of Agriculture, El Reno, OK, USA |
| Abstract: | A qualitative trial-and-error approach is commonly used to define watershed subdivisions through varying a single topographic threshold value. A methodology has been developed to quantitatively determine spatially variable threshold values using topography and a user-defined landscape reference layer. Optimization and topographic parameterization algorithms were integrated to create solutions that minimize the number of sub-watersheds and maximize the agreement between the discretized watershed and the reference layer. The system was evaluated using different reference datasets such as soil type, land management, and landscape form. Comparison of simulated results indicated that the scenario using land management as the reference layer yielded results closer to the scenario subdivided using a constant topographic threshold but with approximately 10 times more sub-catchments and therefore indicating customization of the watershed subdivision to the user-defined reference layer. The proposed optimization technology could be used in adequately applying watershed modeling technology in developing conservation practice implementation plans. |
| Keywords: | evolutionary algorithms GIS watershed modeling watershed subdivision AnnAGNPS soil erosion spatially variable critical source area |