The development of improved soil erosion and sediment yield predictions technology is required to provide watershed stakeholders with the tools they need to evaluate the impact of various management strategies to plan for the optimum use of the land. In this paper, the Hillslope Erosion Model (HEM) was applied to predict the sediment yield from two sets of plots that represented open grazing and manually harvested treatments in Talesh rangelands, Guilan Province, Iran. The model performance was evaluated by comparing predicted and measured sediment yield in standard plots resulting from 24 natural rainfall events. The results showed that the calibration of the default value of erodibility parameter did not improve the initial efficacy of the model, while the development of an appropriate regression function was required to obtain accurate estimates on sediment yield from the study plots. The results of the analyses showed the potential of the model to predict sediment yield for the open grazing and cultivated treatments with coefficients of determination of 0.96 and 0.98, and estimation errors of 20.78% and 47.00%, respectively. The predicted results therefore showed that the HEM could be used as a major tool to estimate sediment yield at plot scale in rangelands.

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