investigation of sediment sources of drainage basin by fingerprinting method

due to successes of fingerprinting method in producing rapid and low-cost information of sediment sources, in this research this method was used in three sub-cathments of chasht-khoran basin in semnan province: amrovan, atari and ali-abad. samples below 63 μm were separated and 15 fingerprinting propertis was measured. in the first stage comparison of means and differentiation analysis were used for determination of the characteristics that can differentiate sediment source as well as possible. in second stage, by minimizing composite multivariate model by optimization methods, the share of each source was determined. the results shown that, in amrovan catchment, for properties consisting of co, ph , kaolinite and k were recognized as optimum composition of sediment tracers which could differentiate sediment source completely. in atary catchment, the optimum composition of tracers are na, co, xlf and kaolinite which differentiate source by %91.7. in ali-abad catchment five parameters were recognized as optimum composite which are :na, xlf, ca, co and smectit which completely differentiated sediment sources. the results of calculated composite multivariate model have shown that upper red formation in amrovan, atari and ali-abad sub-catchment has the highest share in sediment production. the sediment production in these three sub catchment are as follows:35.9, 23.53 and 86.64% respectively. therefore sediment management and control strategies should be performed on these sources.