Changes And Driving Forces Of Land Use And Landscape Pattern In Yixing City Based On RS And GIS

The change of land use landscape patterns is the result of combined action by human and natural activities and other factors,research its changed characteristic and driving force are helpful for protecting the ecological environment,rational utilization of the land resources and sustainable development.Yixing is located in Taihu basin of the Yangtze River Delta,is the center of Shanghai,Nanjing and Hangzhou triangles,with the excellent geographical location and rich natural resources make it become an important developing space in this area.In recent years,with the promotion and implementation of“the 11th five-year plan" and“the 12th five-year plan",Yixing land use structure has undergone tremendous changes,landscape pattern changed accordingly.At present,how to coordinate the three relationships of the economic development,social culture and ecological environment is an urgent problem to be solved in the harmonious development in Yixing.This paper selects the remote-sensing images in 2002,in 2008 and in 2014 in Yixing,based on the RS and GIS platforms,using ENVI and FRAGSTATS,to analyze the land use and the change of landscape pattern of three periods in Yixing,discuss the driving force factors caused by the change.Get the result as follows:(1)Construct the land use classification system in Yixing city:according to the "land use classification" national standards,combined with the situation of spatial resolution of remote-sensing data sources in the research area,to divide the land use types into five first classes of water area(water area and land for water facilities),construction land(town and land for transportation),woodland,farmland and grassland in Yixing city.(2)Obtained the results of three periods of land use by supervised classification in Yixing City:This paper uses maximum likelihood to supervised the classification of the remote-sensing images in three periods,and to evaluate the accuracy of the classified results,the overall classified accuracy are separately 85%,83%and 87%,the KAPPA coefficients are respectively 0.83,0.82 and 0.86,the accuracy of the classification is met the demand.(3)Get the analysis results of land use and landscape pattern in three periods in Yixing City:Based on ENVI,the change features of land use in Yixing city is analyzed from three aspects,including land change,conversion process and change rate;based on FRAGSTATS,the author evaluates the change features of landscape pattern in Yixing city from four aspects,including landscape type area,landscape fragmentation,landscape dominance and landscape diversity and uniformity.It can be seen from the analysis that during the 12 years from 2002 to 2014,the patch area of forest land,arable land and grassland has displayed a decreasing tendency,while the patch area of construction land has been increasing continuously,and the dynamic degree of land use was the highest.The relationship of area transformation among construction land,forest land and arable land was extremely closed;water area didn't have obvious changes due to its particularity.The overall landscape fragmentation of Yixing grew and the degree of external disturbance grew;dominance gap among various landscape gradually shrank;landscape diversity and uniformity became larger,and the development of landscape type tended to be balanced and stable.(4)To explore the driving force factor of the changed land use landscape pattern in Yixing city:According to the changes of land use landscape pattern in Yixing in three periods and the results of data analysis,the author summarizes the driving force of land use in Yixing from four aspects,including natural factor,population size,economic development and policy support.Based on the above,the author puts forward optimizing suggestions and measures,such as controlling the population size,adjusting the industrial structure,promoting the land intensification and standardizing the land management.