Determining Homogeneous Regions of Spatial Distribution of Suspended Load in Aji-Chai River Basin

Deficit of sediment measuring stations and limited number of years containing historical data، have made it difficult to analyze the river’s sediment load. Hence، using methods such as regional analysis to access suitable models to estimate the sedimentary load seems to be necessary. Regional analysis of sediment consists of two parts; 1) determining homogeneous areas and 2) deriving regional models of sediment suspended load of homogeneous regions that involve local characteristics and regional coefficients for the sub-basins being studied. In order to access such models، this study has been conducted in Aji-Chai River basin with area of some 13853 Km2. In the present study، the mean daily sediment production of the sub-basins and 14 physiographic and hydrologic characteristics related to 10 selected sub-basins with 34 years of statistical period were selected as dependent and independent variables، respectively. After determining homogeneous regions a mathematical model for predicting suspended sediment load at each homogeneous region was proposed based on physiographic and hydrologic parameters together with amount of error of each model.