Abstract:

In order to evaluate the impact of South to North Water Transfer Project on environment，it is necessary to understand the existing status of environment before the beginning of the project.Based on RS and GIS technology，five indices，including vegetation index，altitude，landusing，accumulated temperature and annual rainfall，were drawn and applied to evaluate natural environment of the research region.The calculation results were in accordance with the existence.The results showed that:（1）the ecoenvironment quality is good in the research region with the second grade region being dominant;(2)the horizontal distribution of the ecoenvironment quality reveals evident regional diversity—the south of the region is the best，the middle is the second，and the north is the worst;(3)the vertical diversity of ecoenvironment quality is evident—the middle altitude region with good ecoenvironment quality is dominant，the low altitude region locating along the Yalongjiang River is the best in ecoenvironment quality，and the high altitude region occupying less than 20% of the research region is the worst in ecoenvironment quality.

Key words: remote sensing (RS), geographic information system(GIS), integrated evaluation of ecoenvironment, Yalongjiang River, South to North Water Transfer Project