香溪河流域土壤流失脆弱区分布特征研究  

Distribution of vulnerable areas of soil loss in the Xiangxi watershed

作　　者：陈炼钢[1,2] 钱新[1] 施勇[2] 李铭[3] 

机构地区：[1]南京大学环境学院,污染控制与资源化研究国家重点实验室,南京210093 [2]南京水利科学研究院水文水资源与水利工程科学国家重点实验室,南京210029 [3]中国水电顾问集团成都勘测设计研究院,成都610072

出　　处：《中国科技论文》2012年第5期403-408,共6页China Sciencepaper

基　　金：水利部公益性行业科研专项资助项目(200901007);国家自然科学基金资助项目(41105075)

摘　　要：基于香溪河流域土壤流失脆弱性评估与区划结果,在影响土壤流失脆弱性的流域5个自然物理因素中,通过分析年降雨量、土壤可蚀性、坡度、植被覆盖率、沙源与河道距离和土壤流失脆弱性均值之间的统计关系来识别影响土壤流失脆弱性的关键因素。结果显示,地形坡度、沙源与河道距离为香溪河流域土壤流失脆弱性的关键影响因素。在此基础上,进一步分析香溪河流域土壤流失脆弱区的分布与地形坡度、沙源与河道距离这2个关键影响因素之间的关系。结果表明,香溪河流域土壤流失脆弱区集中分布在25°以上的坡地以及河道两侧2km特别是1km以内的区域:25°以上的陡坡区域以占流域41.19%的面积承载了全流域72.1%的土壤流失脆弱区;河道两侧2 km以内的区域以占流域37.01%的面积承载了全流域87.57%的土壤流失脆弱区,特别是河道两侧1km以内的区域以仅占流域20.33%的面积承载了全流域64.48%的土壤流失脆弱区。Based on the soil loss vulnerability assessment and zoning of the Xiangxi watershed, statistical relationships between annual precipitation, soil erodibility, slope, vegetation coverage, cell distance to river and the mean of soil loss vulnerability were analyzed to identify the key natural impact factors. The results showed that, terrain slope and cell distance to fiver are two major factors affecting the soil loss vulnerability in the Xiangxi watershed. Statistical relationships between the distribution of vulnerable areas and the above two factors were further analyzed. The results showed that, 72.1% of the vulnerable areas were distributed in the zone with slopes above 25°, and such zone accounts for 41.19% of the entire watershed; 87.57% of the vulnerable areas were distributed in the zone with a cell distance less than 2 km, whereas such zone makes up only 37.02% of the entire watershed; 64.48% of the vulnerable areas are found in the zone with a cell distance less than 1 km, whereas this kind of zone shares only 20.33% of the entire watershed. This implies that the vulnerable areas of soil loss in the Xiangxi watershed are distributed mainly in the zone with slopes above 25° or in the zone with a cell distance less than 2 km, especially 1 km.

关 键 词：土壤流失 脆弱性 关键因素 分布特征 

分 类 号：S157.1[农业科学—土壤学] X37[农业科学—农业基础科学]