Application Of Remote Sensing Technique In Investigation And Evaluation Of Ecological Environment The Drainage Area Of Minjing Upriver

Application of Remote Sensing Technique in Investigation andEvaluation of Ecological Environment the Drainage Area ofMinjiang UpriverAbstractThe drainage area of Minjiang upriver in Sichuan province of China is the key controlled region of "the layout of ecological environmental construction in China"and one of the headstream area of yangtse rive of China. Because of the disturbance of long-term mankind activity, especially the over deforestation of natural forest, the resource of forest has declined seriously, which brings brittle ecological environment. Remote sensing technique, with its macroscopical, synthetic, dynamic and quick characters, has become one of the most effectively means in the study of modem resource science.In this paper, the areas of forest, land and grassplot resource both in 1990 and in 2000 and the change between the two years were computed accurately by synthetically using the techniques of remote sensing image processing (such as ortho-rectifying, radiation enhancement and multi-source data fusion etc.) and interpreting, information extraction and the functions of spatial data management, statistics and analysis in geographical information system (GIS). It was tested to be precise in the fields. More ever, the method of surface area computing was discussed and analyzed in the paper. This paper was wrote based on the science research project: The remote sensing synthetic investigation and evaluation of ecological environment in the drainage area of Minjiang upriver in Sichuan province of China, which belongs to national ?63?advanced science and technology development plan of China. The present-day state and quality of ecological environment and the controlled factors of environment transition were quickly found out in the study area. The transitional rule of ecological environment was concluded in the study area especially for the reducing velocity and the influencing factor of original forest, which aimed to scientifically evaluate the transition and progressing trend of ecological environment in the future. This paper provided the positional and quantitative data for returning land to forest and grass, building the scientific evaluating model of remote sensing and the scientific standard of returning land to forest and grass, which provideddecision-making basis for sustainable development of social economy.At last, the author has made a program in Visual C++ by using MapObjects ActiveX of ESRI Inc., which can conveniently query, search and statistically analyze the spatial and attributive data of background in the study area.