Temporal and Spatial Signatures of Sediment Transport at the Watershed Scale: An Approach to Understand the Behavior of the Watershed

Sediment yield is affected by many factors, such as climate, geology, geomorphology, land use and human activities. Sediment signatures are the statistic indices or curves that are able to effectively describe the temporal and spatial characteristics of sediment transport and evaluate the ability of the streamflow to deliver the sediment. In this study, the sediment signatures of Upper Sangamon River Basin, which is an intensively managed watershed for agriculture development, are analyzed. Firstly, a semi-distributed model of sediment transport is built up based on the Tsinghua Representative Elementary Watershed (THREW) model, and it is applied to Upper Sangamon River Basin. The result of sediment simulation is analyzed by four sediment signatures, i.e. specific sediment yield, sediment delivery ratio, cumulative sediment curve and effective discharge. The sediment signatures are consistent with each other and accord with the fact of the agricultural production in Upper Sangamon River Basin.