3S技术支持下的汝溪河水土流失动态监测及分析

摘要

为促进水土保持与水土资源利用提供基础数据和决策依据,在3S技术支持下开展水土流失与生态环境动态监测.选取三峡库区汝溪河小流域作为研究区域,根据区域土地利用类型、植被覆盖度信息,并综合所收集的当地水保资料和地形坡度数据等,进行空间叠加分析,确定土壤侵蚀类型、强度分级与分布情况.参照《土壤侵蚀分级标准》,对2014年、2015年2个时期的汝溪河进行水土流失动态分析,并采用转移矩阵法对2个时期土地利用转化方向与转化面积进行合理性分析.研究结果表明:2014—2015年2 a之间,汝溪河小流域的土地利用方式有结构性调整,水土流失分布情况大体趋于稳定,微度水土流失面积略增加,轻度、强度水土流失面积基本持平,中度水土流失略降低,极强、剧烈水土流失情况有所缓解.%In the aim of providing basic data and decision-making basis for soil and water conservation work,we car-ried out dynamic monitoring on soil and water loss and ecological environment under the support of RS, GIS and GPS technologies. With Ruxi River in Three Gorges Reservoir region as study area, we obtained the pattern, inten-sity and distribution of soil erosion through spatial overlay based on information of land-use types, vegetation cover-age and slope gradient.According to Classification standard of soil erosion, we analyzed the dynamic changes of soil and water loss in 2014 and 2015, and adopted transfer matrix to analyze the area and types of land-use changes. Results suggest that from 2014 to 2015,although the land-use patterns of Ruxi River have experienced structural ad-justment, the distribution of soil and water loss were generally stable. The area of microsoil erosion was slightly in-creased, the area of mild and intense soil erosion kept balance,the area of moderate soil erosion was slightly re-duced, and the extremely or severe conditions have been alleviated.