Research On Environmental Quality Comprehensive Assessment Of Ganjiang River Basin Based On Remote Sensing

Ecological environment for human survival and socio-economic development provides a good place,whose quality is a measure of the length of time sustainable economic development is a key factor to complete the construction of ecological civilization.The rapid growth of social economy and the high frequency of human activities have a great impact on ecological environment.The comprehensive and impartial evaluation on the regional eco-environmental quality contributes to getting to timely know the quality of the regional eco-environment and is of guiding significance to the formulation of the policy of eco-environment management and protection,and also gives impetus to the realization of the sustainable development of regional economy.Running in the central and southern of Jiangxi Province,the studregion--Ganjiang River covers about 84,100 square kilometers,accounting for more than half area of the province,the eco-environmental quality of which exerts vital influence on the entire province's society,economy.The comprehensive assessment of the eco-environmental quality of Gan River has a strategic significance on the management and protection of environment and the social economic sustainable development not only in Ganjiang River basin but also in the whole province.This paper is committed to Principle of remote sensing and geographic information system,employing the Landsat TM remote-sensing image of 1994,2004 and the OLI remote-sensing image of 2014 as the main data,making a combination of DEM,statistic and meteorological data.According to the features of research area and assessment criteria of eco-environment,the paper has constructed comprehensive assessment system of eco-environment by selecting 5 assessment factors as organism abundance,vegetation coverage,river density,land degradation and social economy.The comprehensive index methodology makes assessment to eco-environment of researched area and,meanwhile confirms the grade.Based on what has done,the approach conducts quantitative analysis of various indexes and their influence towards ecological and environment quality.Accordingly,the thematic map of index is correspondingly created.The assessment results are as following:A.Biological abundance index and vegetation cover index are relatively high and the combined effect of both influences comprehensive eco-environment index greatly.When the index of both were high,the index of was also high.Therefore,the tendency of the both index is accordance with the comprehensive eco-environment index.B.The soil erosion index ranged from 75.1881 in 1994 to 57.4056 in 2004 and to 44.3158 in 2014.The soil erosion index is reverse index value and the high the index is the worse the soil condition is.The result shows that during the research year,the situation of soil erosion and land degradation improved year by year.C.The social economic index in 1994,in2004 and in 2014 was respectively 63.1636,74.4826 and 85.3571.The index increased on a steep trend indicating that human activities had a more and more serious impact on eco-environmental quality.D.During the year of research,the comprehensive eco-environmental quality index was 65.1626 in 1994,down to 62.9033 in 2004 and up to 67.4433 in 2014.From the year of 1994 to 2004,the change of comprehensive eco-environmental index in Ganjiang region was-2.2593,demonstrating that eco-environmental quality deteriorated slightly.From the year of 2004 to 2014,the change of comprehensive eco-environmental index was 4.54,showing that the condition of eco-environment improved.From the year of 1994 to 2014,the change of comprehensive eco-environmental index was 2.2807,manifesting that the entire situation of eco-environment was taking a turn for the better.During the year of research,the comprehensive eco-environment index was between 55 and 75,which is in sound range,tuning out that in Ganjiang River basin the vegetation cover is high and biodiversity is rich,so it is suitable for human being to live there.E.In the three years studied,Gan River Basin ecological environment quality is mainly good and in general these two levels.The difference between the basin and the excellent level of relatively small proportion,where the difference between the level of three years the proportion of less than 2%,while the proportion in 1994 and excellent 2004 accounted for less than 1%;The proportion of poor grades basin is not low,at between 12% to 17%?Overall,the environmental quality of the Gan River Basin ecology is still relatively high,are in a good overall rating.