Experimental Study on Effects of Different Artificial Vegetation Distribution on Overland Flow

In order to further study effects of vegetation changes on flow parameters of flow velocity,depth and roughness,flow characteristics of overland flow with series of vegetation distribution and discharges on different slope flumes were analyzed.The results showed that the flow Darcy-Weisbath resistance coefficient decreased with the increase of slope degree and Froude numbers.Meanwhile,there was a negative power function relationship between the Reynolds number and the flow resistance coefficient.However,this relationship presented weaker with the increase of slope degree.In short,the hydraulic characteristics were closely associated with the vegetation distribution.In addition,the concept ofthe feature angle of vegetation distributionwas defined to describe the characteristics of vegetation distribution.Through dimensional analysis and comparison between observational data and calculated value,a simple empirical method could be used to calculate the flow Darcy-Weisbath resistance coefficient of overland flow with different vegetation distribution on the slope.