Research On Comprehensive Evaluation Of Ecological Environment In Southeastern Chongqing Based On RS And GIS

This paper takes the southeast area of Chongqing as the main research area,takes Landsat TM and OLI8 remote sensing images in 2000,2005,2010 and 2015 as the main data,supplements other regional natural,social and economic data,and studies regional land use based on RS and GIS technology.On the basis of temporal and spatial evolution,using county scale as the evaluation unit,construct a regional ecological environment quality evaluation system,explore the temporal and spatial changes of ecological environment quality in southeast Chongqing,and reveal the coupling relationship between spatial and temporal evolution of regional ecological environment quality and land use information map.Above,based on the obstacle degree model,reveal the obstacle factors and driving mechanism of the ecological environment quality in the study area,in order to provide theoretical foundation and technical support for the ecological environment quality research in southeast Chongqing.The conclusion is as follows:(1)The overall structure of land use types in the study area is dominated by forest land and arable land.The total area ratios in 2000,2005,2010 and 2015 were 91.32%,90.96%,90.79%,and 90.48%,respectively.In 15 years,woodland,grassland,water area and residential industrial and mining land showed an increasing trend,increasing by1.83%,0.32%,0.16%,and 0.40%respectively;cultivated land and unused land showed a decreasing trend,decreasing by 2.67%and 0.04%.The comprehensive dynamics of land use in 2000-2005,2005-2010,and 2010-2015 were 3.92,3.97,and 0.27,respectively,indicating that the rate of land use transfer was relatively slow.(2)Based on the principal component analysis method,it is known that the main factors affecting the quality of the ecological environment in 2000 were the per capita arable land area,the per capita GDP,the harmless treatment rate of urban domestic waste,and the per capita disposable income in rural areas;The main factors are the per capita arable land area and the rural Engel coefficient;in 2010,the per capita arable land area,science and technology,education investment accounted for GDP,the tertiary industry accounted for GDP,and per capita GDP,2015 was the level of urbanization,per capita gross regional product Value and annual precipitation.From 2000 to 2010,the per capita arable land area was the main factor affecting the quality of the regional ecological environment,while in 2015 it was mainly the level of urbanization.(3)Through the analysis of the temporal and spatial evolution of the ecological environment quality in southeastern Chongqing from 2000 to 2015,it is found that the area with“excellent”ecological environment quality has decreased by 535.57km~2,from the north to the southeast,the area with“good”has increased by 688.27km~2,Expanded from the northern region to the central region and the southeast region,the graded"normal"area increased by 78.98km~2,from the east and northwest regions to the central and southern regions,and the graded"poor"area decreased by 594.25km~2,from the southwest distribution area to the north and south.The southeast region has shrunk;the“very poor”area has increased by 362.57km~2,expanding from the west and southeast regions to the north and southeast regions.(4)From the analysis of the ecological environment quality in some areas,it can be seen that the quality of the"excellent"ecological environment in Qianjiang District has been reduced by 670.22km~2,and the corresponding map type is forestland?arable land,grassland?arable land;Shizhu County has the highest ecological environment quality,without"The distribution of"general","poor"and"very poor"is largely due to the excellent natural environment;the areas of"excellent"in Xiushan County and Youyang County have increased by 2.26km~2 and 10.53km~2,respectively.The deterioration of the ecological environment quality in Wulong County has intensified,and the"extremely poor"area has increased by 303.89km~2.The corresponding map types are forest land?residential industrial and mining land,grassland?residential industrial and mining land;the ecological environment quality of Pengshui County is the second,almost none The distribution of grades"excellent".(5)Based on the research results of the obstacle degree model,it can be seen that the rapid economic development in the study area during the 15 years is the direct factor affecting the decline of the local ecological environment.The problem of insufficient resources and urban pollution has become more and more prominent;the pressure system and the state system have a clear upward trend,The response system is at a very low level and continues to decline.