Study of Sediment Source Calculation in Small Watershed in Pisha Rock Area Through Grain Size Analysis Method
WANG Xiao (Suide Soil and Water Conservation Scientific Experiment Station, YRCC, Suide, Shaanxi, 718000)
Sediment source of small watershed is the key component of soil erosion study, at the present time, the data of runoff and sediment are used with the statistical analysis method to determine sediment yields from different geomorphic location and different erosion patterns both in international or domestic researches. Grain size analysis method is applied in the paper to analyze the sediment source in typical small watershed in different erosion patterns in Pisha rock area. The calculated results demonstrate that small watershed sediment mainly comes from gullies that makes up of 79.39% to 84.89% of total sediment yield of the watershed, while sediment yield from slope accounts for 15.86% to 20.61% of the total.