Soil Erosion and Deposition Modeling Using ArcGIS™

摘要

The Unit Stream Power Erosion and Deposition model (USPED) was used to model eight contiguous watersheds (approximately 28,500 acres) within the area of Fort Bragg located near Fayetteville, North Carolina. ArcGIS™ software was used to develop the USPED computer simulation that predicted where erosion and associated deposition was likely to occur within a given watershed. Model input parameters included a 2-meter digital elevation model (DEM) data, land cover values, soil erodibility values, and a rainfall factor. Results of the simulation predicted that the mean annual net erosion for all watersheds was less than 1 ton (short) of soil per acre per year (tn/ac/yr). Erosion was predicted for 71% of the modeled area, and deposition was predicted for 29% of the modeled area. The model predicted that several watersheds included areas where severe erosion and associated sediment deposition was likely to occur. Field verification confirmed that erosion and associated sediment deposition had indeed occurred in these areas. Model results were used to approximate the total suspended load and associated turbidity [nephlemetric turbidity units (NTU)] of streams associated with each watershed. Turbidity was estimated using the mean amount of net annual erosion predicted by the model and runoff values associated with annual precipitation. Estimated turbidity values ranged between 186 and 541 NTU.