Development and Application of a Methodology for Sediment Source Identification. I: Modified Unit Sedimentograph Approach.

Identification of sediment source areas within a watershed is useful for designing appropriate management alternatives that reduce sediment losses. In most watersheds, data collection programs are present at the stream gauging station, and sediment source identification must be treated as an inverse problem. A physically based watershed-scale surface flow and erosion model, KINEROS was utilized as the modeling tool in this study. A modified unit sedimentograph approach was used for source identification based on hydrograph and sedimentograph data collected at the watershed outlet. Data from several events were examined over two small watersheds, and a statistical procedure was employed to assess the erosion vulnerability of different regions in the two watersheds. These results were presented in the form of maps to obtain a spatial picture of potential sediment generating areas. A statistical analysis was also utilized to determine if erosion potentials of different regions of a watershed were significantly different. It appears that identification of source areas is possible when a limited number of regions are contributing sediments. [ABSTRACT FROM AUTHOR]