Investigating of suspended sediment yield in Ziarat Drainage Basin, Gorgan in different seasons using sediment fingerprinting technique

Soil erosion is the most serious and irreversible threat to sustainable development. According to the increasing rate of soil erosion and sediment yield, the objective of this study was to determine relative contribution of sediment sources in Ziarat catchment in fall, winter and spring seasons by using of sediment fingerprinting technique. In view of this, 43 samples from sediment sources including rangeland and cultivated land as surface erosion and stream bank and road verges as sub-surface erosion as well as 14 samples of suspended sediment at outlet of catchment were collected and concentration of geochemical tracers, organic carbon and 137Cs were measured. The optimum set of tracers was selected by using the Kruskal-Wallis H test and discriminant function analysis. Finally, the relative contribution of sediment sources was determined using mixing model in different seasons. The results showed that the maximum relative contribution was related to surface erosion in winter and spring seasons. Sub-surface erosion in spring season with 60.4% was also contributed a large amount of sediment yield. The results of this study can be used to select the management strategies in soil erosion and sediment control of Ziarat catchment in different seasons.