ANALYSIS OF REGIONAL SUSPENDED SEDIMENT IN GORGANROUD DRAINAGE BASIN BY USING REGRESSION EQUATION

摘要

Suspended sediment yield data could be used for estimating soil erosion in drainage basins. The objective of multiple regression analysis is to use the independent variables (whose values are known) to predict the single dependent value selected by the researcher. In this research, 11 stations were selected in Gorganroud drainage basin according to area of upland catchments, geology, climate, vegetation cover and etc. The potential factors that are effective in suspended sediment yield were identified. Using the mean load with in discharge data, 30 years mean suspended sediment load of each station was estimated Multiple regression analysis was used to obtain the best statistical relationship between suspended sediment yield data and other independent variables. According to the final model, the percentage of distributed forest area and mean annual discharge vary together and have positive relationship with sediment yield Inversely the percentage of area of resistance and relatively resistance geological formation have negative effect in sediment yield. These three independent variables explain more than 96% of mean suspended sediment load variation in Gorganroud basin and have 19 % standard error in their prediction.