四川小流域土地利用和土壤侵蚀的分类及耦合关系研究

Classification and Coupling Relationship between Land Use Types and Soil Erosion of Small Watersheds in Sichuan

利用两步聚类、相关分析等方法,对四川省"长治"工程涉及的212条小流域土地利用和土壤侵蚀状况进行分类并分析其耦合关系,结果表明:土地利用聚为四类,以坡耕地、梯田和经果林为主的三类、四类流域条数占流域总条数的59.9%;土壤侵蚀聚为四类,以无明显侵蚀、轻度侵蚀为主的四类、一类流域条数占流域总条数的74.6%。土地利用与土壤侵蚀之间的关系为:以林地和难利用地为主的流域侵蚀程度最轻,强烈及强烈以上的侵蚀主要发生在以坡耕地为主的流域内。

The paper classifies the status of land use types and soil erosion of two hundred and twelve small watersheds involved in'Key Treatment Projects of Soil and Water Conservation in the Upper Yangtze River' Project in Sichuan and analyzes their coincidence relationship by using the methods of two-step cluster and correlation analysis.The outcomes show that the land use types are divided into four categories,and the number of the third and the fourth types of watersheds dominated by sloped land,terrace,economic fruit forest account for 59.9% of the total number.Soil erosion is divided into four categories,and the number of the first and the fourth types of watersheds dominated by insignificant erosion and slight erosion account for 74.6% of the total number.The relationship between land use types and soil erosion is that the soil erosion degree of the watersheds mainly are woodland and unused land is the lightest and the watersheds mainly are sloped lands is severe or the worst.