Evaluation Research Of Regional Land Use Change And Ecological Security Based On Remote Sensing And GIS

Land resources is the important foundation of human survival and development, It is experiencing rapid urbanization process in recent years.Ecological and social problems in the urban construction land expansion wave, natural and agricultural landscape was collapsing in the process of gradually highlight. With the enhancement of the human to the ecological environment protection consciousness, ecological security problems have been widely cause the great attention of experts and scholars and government departments and become the research hot topic at home and abroad. Ecological security evaluation has become an ecological security warning system and the important foundation of environmental management.This paper selects the southwest sichuan basin leshan as the research object. Visual interpretation of image data, To establish Covered in leshan city in 1992-2013 benchmark land use database. Using dynamic change model and transfer model, overlay buffer analysis and other methods of LUCC in the study area spatial structure and the regional difference is analyzed. And based on P- S- R model, chooses the index of ecological security of leshan 16 evaluation system, GIS spatial analysis get leshan city ecological security evaluation results, research shows that:Firstly,Land use change significantly,Land use to forest land,cultivated land is given priority to,accounting for the study area is a total area of about 95%.Quantity change, the area of construction land continue to increase,During the period of 21 years, area of 6442.65hm2,increases to 6442.65 hm2,area increased by 8817.03 hm2,Cultivated land showed a trend of first increased after decreased, on the whole area is reduced,Woodland appears increasing trend after reducing first,Water area change significantly in 2002, covers an area of 20018.07 hm2, in 1992 and 1992, area of 14436.63 hm2, 13093.92 hm2,respectively,Grassland and unused land area is steadily increasing.Construction land and unused land value is the largest,Dynamic attitude from 1992 to 2013 were 6.51%, 7.52% respectively,Water in the 1992-2002 appeared more obvious negative dynamic change,Cultivated land, forest land, grassland more gently。Secondly, Spatial pattern of big differences,Class space transfer has certain regularity,Cultivated land to construction land in the downtown district, jiajiang, emei city, wutongqiao district, is the most widely distributed, presented by the city center to spread to the characteristics of forest land and farmland conversion occurs mainly in the flat area, mutual conversion of forest land and grassland and the change of forest land to unused land concentration distribution in jinkouhe, EBian and the terrain slope, mabian of high mountain, basic belongs to the state of natural succession.Thirdly, Spatial pattern of the big differences.Ecological security composite index in the study area showed a trend of decrease in total, but in the 2002-2013, receded. Composite is reduced from 0.691 in 1992 to 0.657 in 2002, in 2013 began to recover, a value of 0.672; From the point of view of ecological security hierarchy sorting, each year of ecological security level area is a sort of high security > high safety > moderate > security > security.Forth, Land ecological security condition showed obvious regional differences. County from the partition of ecological security evaluation results, low safety, light ecological levels are mainly distributed in the downtown district, wutongqiao district, jingyan county during, qianwei, jiajiang, moderate security level and above are mainly distributed in mabian autonomous county, EBian autonomous county, muchuan county, jinkouhe, fandian, emei city, including the fandian, jingyan county during, jiajiang ecological security index change is most obvious, showed a trend of decrease.