Multiscale simulation of land use impact on soil erosion and deposition patterns

Helena Mitasova, Lubos Mitas, William M. Brown

 

Abstract
Sustainable use of natural resources requires coordination of conservation efforts between a diverse group of individuals and agencies which view and manage the landscape at different scales, from field level by a farmer, to entire watersheds by state or federal agencies. To better support the multilevel management we propose a methodology for watershed characterization and erosion modeling at multiple scales and levels of complexity. The simple, approximate estimates are performed by modified USLE and Unit Stream Power based model, more detailed simulations of impact of land use practices is supported by a distributed soil erosion model SIMWE (SIMulated Water Erosion). The SIMWE model is designed for applications in areas with spatially variable terrain, soil and cover conditions enabling the capture of spatial aspects of watershed internal behavior. The model is based on the Monte Carlo solution of bivariate water and sediment flow continuity equations, and is being currently extended to support modeling with spatially variable resolutions. The implementation uses multipass simulations, starting from a low resolution for the entire watershed and continuing with linked-in simulations performed at higher resolutions within subareas where more detailed data are available and their use is necessary due to the complexity of terrain/land-use configuration. Using the outlined concept and tools, we investigate the impact of land use on erosion and deposition patterns in  different study areas: We perform multiscale simulations for the current conditions aimed at identification of important sediment sources and sinks, and we evaluate the use of the results for finding effective spatial distributions of conservation measures.

Authors: Helena Mitasova, Geographic Modeling Systems Laboratory, Department of Geography, 220 Davenport Hall, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA, ph: 217-333-4735, fax:217-244-1785, email: helena@gis.uiuc.edu

Lubos Mitas, National Center for Supercomputing Applications, 405 N. Mathews Ave, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA

William M. Brown, Geographic Modeling Systems Laboratory, Department of Geography, 220 Davenport Hall, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA

Sponsoring organizations: US Army Construction Engineering Research Laboratories, Champaign, Illinois, USA and University of Illinois at Urbana-Champaign, Illinois, USA