گزينش روش نمونه برداري مناسب و مقايسه روش هاي هيدرولوژيك برآورد بار معلق رودخانه (بررسي موردي در حوزه آبخيز طالقان)

Selection of Sampling Approach for Comparison of Hydrological Methods of Estimating Suspended Sediment Load (Case study: Taleghan Basin)

Information is required for understanding of river suspended sediment for design and construction of water recourses management projects. Due to the importance of suspended sediment load and insufficient hydrometric gauging stations, this research was conducted in Glinak hydrometric station of Taleghan Rood basin in order to compare the sediment delivery yield based on hydrologic methods. It is necessary to determine the best method in the condition of deficit continuous data for the estimating suspended sediment from hydrological methods and evaluation of the sampling method to find out the best fitting amount on suspended sediment load. The results of this research showed that change in the absolute error in the methods has a direct relation with the variability of suspended sediment data. Also in some approaches, systematic sampling method and in the others methods combined sampling strategy showed the most appropriate results. Meanwhile the accuracy of randomized sampling method was the highest. Among hydrological methods, the "FAO" and the "Mean load within discharge classes" methods by MAE of 2170.9 and 2179.6 respectively had 1:he most suitable results of the estimated suspended sediment for Taleghan Roud. Providing at least two sampling of instantaneous suspended sediment per week to increase the accuracy and precision of hydrological methods was as another result of current research.