Agriculture & Forestry, Vol. 63 Issue 3: 23-32, 2017, Podgorica 23 DOI: 10.17707/AgricultForest.63.3.03 Abdulvahed KHALEDI DARVISHAN, Morteza BEHZADFAR, Velibor SPALEVIC, Patrick KALONDE, Abdessalam OUALLALI, Sabri el MOUATASSIME 1 CALCULATION OF SEDIMENT YIELD IN THE S2-1 WATERSHED OF THE SHIRINDAREH RIVER BASIN, IRAN SUMMARY Soil erosion by water as a natural process can occur in all climates and zones and change all landforms. As the measuring of soil erosion is costly and time consuming process, dozens of erosion prediction models have been developed and the aim of the majority of all of them is to predict average rates (often an annual average rate) of soil loss from an area such as a plot, a field or a catchment/watershed under various land management techniques. On the other hand, outflow is the most important element of the hydrological cycle and that is why it is important to determine it as accurately as possible by measuring and predicting. Therefore, the IntErO (Intensity of Erossion and Outflow) model based on the EPM (Erosion Potential Method) method was used for calculation of outflow and sediment yield in the S2-1 watershed of Shirindareh River Basin in the Northeast Iran with the area of 46.77 km2. According to the results, the predicted peak discharge was 101 m3 s-1 for the incidence of 100 years and the specific sediment yield was 267 m3 km-2 year-1. According to the previous studies and topographic characteristics, the river basin watershed belongs to the V category and has very weak erosion. The results of the present study and previous experiences of the other researchers revealed that the IntErO model can be used to estimate soil loss in the other regions similar to Shirindareh River Basin. Keywords: IntErO, Runoff, Specific sediment yield, Shirindareh Watershed, Soil erosion INTRODUCTION Watersheds are in fact often affected by natural disasters, above all floods, overflows, inundations, erosion problems, landslides and pollution (Tazioli et al. 1 Abdulvahed Khaledi Darvishan (corresponding author: a. khaledi@modares.ac.ir), Department of Watershed Management Engineering, Faculty of Natural Resources, Tarbiat Modares University, Noor, IRAN, Morteza Behzadfar, Faculty of Natural Resources, Tarbiat Modares University, Noor, IRAN, Velibor Spalevic Department of Geography, Faculty of Philosophy, University of Montenegro, Niksic, MONTENEGRO, Patrick Kalonde Environmental Science and Management Department, Lilongwe University of Agriculture and Natural Resources, Faculty of Natural Resources, Lilongwe, MALAWI, Abdessalam Ouallali Department of geology, Abdelmalek Essaadi University, Faculty of Science, Tetouan, MOROCCO, Sabri el Mouatassime Faculty of Technical Sciences, University Soltane Moulay Slimane, Béni Mellal, MOROCCO. Presented at the 7th International Symposium of Ecologists (ISEM7), Sutomore, Montenegro. Notes: The authors declare that they have no conflicts of interest. Authorship Form signed online.