基于RS和GIS的重庆市忠县土壤侵蚀时空演变分析

RS and GIS-based analysis on spatial-temporal evolution of soil erosion in Zhong county,Chongqing city

以重庆市忠县为研究区域,以1990、2015年的Landsat TM和Landsat TM8 OLI为主要数据源,基于RS和GIS并结合实地采样的土壤遥感调查数据,获取研究区域土壤侵蚀数据,并进行土壤侵蚀空间分布格局与时空动态演变规律的分析。结果表明,两个时期土壤侵蚀总体格局基本都是以微度侵蚀为主,1990、2015年所占的面积比例分别为44.67%和54.88%,轻度、中度和强度侵蚀三者之和分别为50.99%和41.59%;微度侵蚀的面积呈增加的趋势,而其他侵蚀类型呈减少的趋势;剧烈侵蚀面积减少的幅度最大,为25.77%;轻度侵蚀减少的面积最大,为101.16 km2;微度侵蚀与轻度侵蚀之间的转换数量较大,转换相对剧烈,极强度和剧烈侵蚀与其他侵蚀类型之间转移变化量相对较小。

Based on Landsat TM,Landsat TM8 OLI,RS,GIS and field remote-sensing survey data in 1990 and 2015,the spatial distribution of soil erosion pattern and its spatial-temporal evolution characteristics in Zhong county,Chongqing city were analyzed.The results shows that in these two periods,soil erosion was dominated by the micro erosion.The proportions of the soil erosion in 1990 and 2015 were 44.67% and 54.88%,respectively.The sumsof area proportions of the area in the mild,moderate and strong soil erosion type in 1990 and 2015 in this area is 50.99% and 41.59%,respectively.As the area of micro erosion increases,the area of other erosion types decreases.Strong erosion area showed the sharpest cut(25.77%)and mild erosion area narrows mostly(101.16 km2).The great conversion happens between micro erosion and mild erosion,as the conversion between extreme strong erosions and strong erosions with other erosion types were relatively smaller.