Estimate of Continuous Sediment Graphs in a Basin, Using a Composite Mathematical Model

The aim of this study is to present continuous simulation efforts of soil and streambed erosion processes, as well as the comparison of computed sediment load values with field measurements. For this reason, a composite mathematical model, consisting of three submodels, is applied to the basin of Kosynthos River (district of Xanthi, Thrace, northeastern Greece): a rainfall-runoff submodel, a soil erosion submodel and a sediment transport submodel for streams. The rainfall-runoff submodel that is used for the computation of the surface runoff and the streamflow in the sub-basins, is the deterministic distributed hydrologic model HEC-HMS 3.5. For the estimate of soil erosion in a sub-basin, the model of Poesen (1985) is used, while for the estimate of sediment yield at the outlet of a sub-basin, and finally at the outlet of the whole basin, the stream sediment transport model of Yang and Stall (1976) is used. The statistic efficiency criteria utilized for the comparison between computed and measured sediment discharge values at the outlet of the whole basin, provide satisfactory values. Therefore, it is concluded that the continuous hydromorphologic modeling can be successfully applied to Kosynthos River basin.