Research On Environmental Quality Comprehensive Assessment Of Dongjiang River Basin In Huizhou

Ecological environment is a basic element and material resource for human survival and development, and it can promote and restrict the development of human society. Our ecological environment and its sustainable development were strongly influenced by the intense human social and economic activities. Dongjiang River basin in Huizhou, located in the middle of Dongjiang River Basin in Guangdong Province, it is an economical developed region which has also a good ecological environment. An environmental quality assessment has been conducted on this basin to protect more and improve the ecological environment and therefore to implement a strategy for sustainable development of the Dongjiang River basin in Huizhou.In this paper, based on remote sensing and geographic information system technology, the assessment indicators were selected by analyzing the remote sensing images, the environmental monitoring data and the socio-economic statistics data of the years 1990,2000 and 2005. The entropy analysis was used to determine the weights of the indicators. By establishing the environmental comprehensive quality assessment system of Dongjiang River basin in Huizhou, and analyzing the ecological environment change with time, the ecological environment characteristics and its behaving laws, strategies and measures were proposed to control river basin ecology. The main conclusions of the research are:(1) Considering the ecological environment features of Dongjiang River basin in Huizhou and by taking multi-temporal remote sensing data as the main data source and by combining soil data, environment monitoring data, land use classification, vegetation coverage, soil erosion quantity, accumulated temperature over 0°, elevation, slope, GDP per capita, population density and annual rainfall were chosen as the indicators of the environmental quality assessment. By using entropy analysis to determine the weight of the indicators and by applying information entropy to carry out environmental quality assessment, one can eliminate the perturbation of subjective factors on the evaluation and make the evaluation results agree better with the objective reality.(2) Dongjiang River Basin in Huizhou has a high environment quality, it was at its best in 1990, but the environmental quality degrade later in 2000, then after the environmental protection, its quality gradually improved in 2005.(3) The land use structure should be further optimized, and the nature grass, forest, nature wetland and lake should be better protected. Firstly, it is necessary to bring about a coordinated development of population, economy, society, resources and environment; secondly, develop cycle economy, and promote industrial restructuring finally, protect and monitor the environment, take the way of development with protection.