Enhancement of the SATEEC soil erosion and sediment modeling system with better sediment delivery ratio module

The soil erosion has been one of the biggest concerns in Korea as well as in other countries because of its impacts on ecology and water quality in the receiving water bodies. Among many computer models simulating soil erosion at field and watershed scale has been integrated with the Geographic Information System (GIS) because its nature is essentially spatial. The prototype and enhanced version of the Sediment Assessment Tool for Effective Erosion Control (SATEEC) system utilizes the area-based sediment delivery ratio methods. However the sediment delivery mechanism is not solely dependent on the watershed area. Thus new sediment delivery ratio estimation module was automated in the SATEEC system by considering watershed area, watershed relief ratio, and average Curve Number for all sub watersheds in the watershed having each cell as an outlet. The estimated sediment delivery ratio shows the spatial variability and could provide soil erosion decision makers with better information regarding soil erosion and sediment yield behaviors. This result can be used to identify the most critical areas and assess the effects on sediment yield of soil erosion best management practices implemented in the critical areas. However, new sediment delivery ratio method needs to be extended for its application for the bigger watershed because of limitations in ArcView GRID library in the number of processes. Thus the works are undergoing to port the ArcView 3.x based SATEEC system into the ArcGIS platform.