基于RS和USLE的红壤丘陵区小流域水土流失量估算

Estimation of soil erosion in red earth hilly area based on RS and USLE

采用野外调查采样、室内分析测定、遥感(RS)技术、数学模型等研究方法,以湖南省资兴市东江水库上游光河桥小流域为例,计算出了美国通用土壤流失方程(USLE)中各单项因子值,对该流域水土流失量进行了估算。结果表明:该流域的土壤可蚀性因子(K值)介于0.14～0.42 t.hm2.h.hm-2.MJ-.1mm-1之间,平均为0.27 t.hm2.h.hm-2.MJ-.1mm-1,属于中等可侵蚀性土壤;土壤侵蚀模数在0～3 817 t.hm-2.a-1之间,平均侵蚀模数为78 t.hm-2.a-1,处于强度侵蚀等级,流域的土壤侵蚀量达到292 266 t.a-1。

With Guangheqiao basin in Zixing City of Hunan Province as the study area and by adopting field investigation and sampling,laboratory measurement and analysis,RS techniques and mathematical modeling,the authors calculated each parameter of the universal soil loss equation（USLE） regarding this tributary and estimated the soil erosion.The results show that the value of K parameter（soil erodibility） is between 0.14 to 0.42 t.hm2.h.hm-2.MJ-1.mm-1 with a mean of 0.27 t.hm2.h.hm-2.MJ-1.mm-1.This implies that the soil erodibility is at the medium level.The soil erosion module varies from 0 to 3 817 t.hm-2.a-1 with a mean of 78 t.hm-2.a-1,and the soil loss has reached 292 266 t.a-1.Thus,the soil erosion intensity is high.