Effects of the Implementing Land use-based Scenarios in the Prioritized Sub-Watersheds on Soil Erosion and Sediment Yield of the Glazchai Watershed, Oshnavieh, Iran

Land use patterns, agricultural activities, and decreased vegetation have accelerated land degradation processes. Therefore, implementing land and vegetation-based management measures and utilizing land resources according to suitability/capability is essential to achieve integrated watershed resources management in critical watersheds. Hence, the present study was planned to evaluate the changes of erosion and sediment yield to evaluate management scenarios based on land capability in the high priority sub-watersheds of Glazchai watershed Oshnavieh, West Azerbaijan province, Iran. Therefore, the land capability of priority sub-watersheds was first extracted according to the FAO method. The soil erosion, sediment yield variability, and the maximum discharge were estimated using the IntErO model. The results showed that six percent of the study area in studied sub-watersheds did not follow the land capability rules. The forest land use had a 2.21% net increase. Also, the good rangeland area had a net change of 1.2% compared to the current conditions. In this regard, the allocation of land capability in these areas will reduce the erosion amount, sediment yield, and the maximum discharge of the watershed by 7.1 and 1.33%, respectively. At the watershed scale, the amount of specific sediment yield is also reduced by 12.6 m3y-1km-2. The present study results can provide a suitable management approach for planners and policymakers to make a sound decision regarding the land use-oriented measures in high-priority areas at the watershed scale.