The effect of plant height, vegetation cover and density of Vicia Dasicarpa and Villosa on reducing runoff and sediment

Soil erosion and sedimentation is one of the main problems in most of watersheds in Iran and a fundamental limitation against sustainable development. The usage of vegetation cover is the cheapest and most suitable approach for soil conservation. In the present study, the height, vegetation cover and density of Vicia Dasicarpa and Villosa Vicia investigated on reducing runoff and sediment. The experiments conducted using standard plots with dimensions of 22×1.8 m, slope of nine percent and east direction; so that, nine experimental plots including three treatments and three replications installed and performed in the form of randomized complete block design. Runoff sampling was conducted from the tanks installed at the end of each plot, and the parameters of vegetation surface cover, vegetation density and plant height were measured at each sampling time. Then, the means of measured parameters were statistically analyzed and compared using Duncan Test. According to the results, the maximum runoff  (97%) and sediment (94%) reduction were observed for Vicia Dasicarpa during the experiment. Also, it was detected that plant properties such as vegetation cover and density have a great correlation with runoff and sediment reduction which means soil and water conservation. Therefore, selecting the cultivar and plant species is an important step to increase the efficiency of this biological method. Based on the findings, in order to conserve soil and water as well as assisting the livelihood of the watershed residents, the use of legumes compatible with rainfed conditions having appropriate properties such as strong root, stem system and coverage along with initial irrigation at important growth stages of the plant in drought conditions is recommended.