Optimization of Water Discharge and Suspended Sediment Relationship in Sediment Record Stations of Gharesoo River

In this study, using Sediment rating curve models USBR, seasonal model, monthly model, data model based on separating dry and wet seasons, data separation based on flow measurement time (months of low water and high water seasons) and separation of data based on months with no green vegetation and green vegetation] on 6 hydrometric station in Gharesoo River in Golestan Province with aim of selection of appropriate method for estimation of suspended sediment. Results of homogeneity test data showed that daily discharge at all stations was homogeneous. For selection of the best model index of mean square error and correlation coefficient was used. The results showed that models of months without vegetation had lowest accuracy, and the model based on the season had higher correlation coefficient and less mean square errors. So that the winter season was the most suitable models for the estimation of suspended sediment among the models and also summer and autumn models had a higher accuracy. Also, a linear model in which data has been done separately also have the low correlation and mean square error.