用粒度分析法计算砒砂岩区小流域泥沙来源的探讨

摘要

小流域泥沙来源是土壤侵蚀研究的重要内容，目前国内外主要利用径流泥沙资料，采用统计分析方法来确定小流域不同地貌部位及不同侵蚀类型的产沙量。采用粒度分析法对砒砂岩不同侵蚀类型区典型小流域泥沙来源进行分析计算的结果表明：小流域泥沙主要来自于沟谷地，其产沙量占小流域总产沙量的79.39%～84.89%；沟间地产沙量占15.86%～20.16%。%Sediment source of small watershed is the key component of soilerosion 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.