Determining the contribution of sub-basin sediment yield using geochemical and radionuclide tracers in Ashan drainage basin, East Azerbayjan Province

The main objective of this study was to determine the contribution of sub-basin sediment yield using geochemical and radionuclide tracers in Ashan drainage basin. In view of this, 30 sediment samples were collected from 5 sub basin outlets and radionuclide tracers including 210Pb, 228AC, 226Ra, 137Cs and 40K and geochemical traces including calcium, iron, potassium, magnesium, Mn, Na and organic carbon were measured. The optimum set of tracers was determined using Kruskal Wallis test and discriminant function analysis. The relative contribution of sub-basin sediment yield was determined by using Bayesian uncertainty un-mixing model based on the optimum set of tracers. The tracers including 226Ra, 137Cs and 40K, Mn and Ca were selected as optimum set of tracers with 80% correction of determination. The results showed that the sub basin of Heris (3) has the highest amount of sediment yield (70.1 %). The most lithology of this sub basin is pyroclastic and clay stones and soil conservation plans in order to reduce sediment yield should be focused on this sub-basin.