Effect of land use on Runoff and sediment yield in different slope gradients and intensity using rainfall simulator

Assessment of Changes in runoff and soil erosion in adjacent soils under different land use is essential. This study aimed to investigate the interaction effects of slope gradient and rainfall intensity on runoff and sediment production on rangeland and agricultural fields in the Senobar watershed using rainfall simulator. Therefore, based on the topographic map of the region, three-classes of slope 0-10, 10-30 and more than 30% were selected. Also, three rainfall intensity values 0.9, 1.1 and 1.4 mm min-1 to correspond return periods of 10, 25 and 100- years, respectively were chosen. Then, based on workable unit map, 18 points were identified in different areas in the rangeland and agriculture randomly. The results of the analysis of the main effects of the variables on runoff and sediment yield data showed significant differences for slope gradient and different intensities in Senobar watershed. The interaction effect between slope gradient and intensity of any of the parameters measured in the two land uses does not show significant difference in five percent confidence level. The results also show that the volume of runoff and sediment yield in rangeland was higher than in agriculture.