土地利用/覆盖变化对长江流域非点源污染的影响及其信息系统建设

随着社会经济的发展，不合理土地利用方式/土地覆盖变化造成的非点源污染已成为长江流域水环境不断恶化的重要原因之一。长江流域，特别是长江中上游地区是我国水土流失的重点地区之一。水土流失将泥沙和土壤中的营养元素、残留的农药、化肥及动植物残体带入水体，使水体悬浮物、化学需氧量、总磷、总氮等含量增加，水质污染加重，这是造成长江干流汛期水质变差的主要原因。虽然针对长江流域的研究很多，但土地利用/覆盖变化对长江流域水质的非点源污染却一直没有引起人们的足够重视。在分析当前长江流域非点源污染现状和3S技术的基础上，提出建立基于土地利用/覆盖变化的长江流域非点源污染模拟信息系统，并结合3S技术勾画出该系统的框架。该系统的建设和应用，对维持流域生态平衡，采取合理的土地管理方式，保护长江水资源的可持续利用，特别是三峡库区的生态安全具有重要意义。

RELATIONSHIP AND SIMULATION INFORMATION SYSTEM OF LAND USE/COVER CHANGE AND NON-POINT SOURCE POLLUTION IN YANGTZE RIVER BASIN

With the development of our society,irrational land use/cover change has become one of the important factors in water environment deterioration in Yangtze River Basin.Soil erosion is one of the most serious eco-environment problems in Yangtze River Basin in China.Silt,nutritive element of soil,residual pesticide,fertilizer,bodies of animal and plant are constantly transferred into water bodies with soil erosion.As a result,the amount of SS,COD,TP and TN increased continually and the water quality is continually declined.During the flood season,the pollution of water quality in mainstream of Yangtze River is mainly caused by non-point source.There are many studies related to the area of Yangtze River basin,but little research which is focused on the NPS pollution caused by land use/cover change.Based on the actuality of non-point source pollution in the Yangtze River Basin and the development of 3S techniques,constructing an information system to simulate the relationship of land use/cover change and non-point source pollution in Yangtze River Basin is reported in this paper.At the end of this paper,the framework and functions of the simulation information system are sketched out.With the support of the system,some benefits will be brought to the Yangtze River Basin.