Investigating the Effect of Surface Gravel Cover on Runoff and Soil Erosion with Simulating Runoff

Surface gravel cover is an important factor for contoroling of soil erosion in dry area specially in area that plant can not grow because of excessive dryness and salinity. The objective of this study was investigation effect of different surface gravel cover on runoff and sediment yeild. For this porpose, 36 field plots with 20 meter length and 0.5 meter width at 3 percent slope were constructed in research field of agriculturev faculty, Shahrekord university. Treatments were including four level gravel cover (0, 10, 20 and 30 percent) and three surface flow rate (2.5, 5 and 7.5 L min-1) at three replications that expriment was done in a factorial with randomized complete block design. The results showed that as increasing surface gravel cover decresed the runoff rate and sediment yield significanty (p<0.001) in comparision with control treatment as linear and exponential, respectively. Aso, statisticaly comparision of the effect different gravel cover on runoff and sediment indicated that the effective gravel cover on runoff and sediment was different with increasing surface flow rate, as suitable gravel cover for surface flow 2.5 and 5 L min-1 was 20 percent and for surface flow 7.5 L min-1 was 30 percent gravel cover.