Land Use Change Of Coastal Counties And Cities Based On CA-markov Model

Based on the remote sensing image of Qidong in 1990,2002 and 2014,this paper comprehensively applied RS,GIS,SPSS statistical analysis,CA-Markov Model and land use environmental effect index to analyze the land use current situation,change and its effecting force of Qidong city from 1990 to 2014,and then predicted its land use structure in 2026.On the basis of the above analysis,this paper used multiple environmental quality indexes to analysis the environmental effects of land use change,and we made suggests about study area land sustainable use according to the present and future land use structure and its environmental effect.The main conclusions are as follows:(1)The status of the study area land use type are diverse,the farmland and constructive land are still in dominant place,the land use spatial structure showed that the characteristics of serial differentiation from coastal to inland;There are significant differences in land use structure among coastal areas,riverside areas and other areas.(2)From 1990 to 2014,the structure of study area land use has been changed from the farmland as the main body to the farmland as important as construction land;the speed of change is rapid and the amplitude is large,however,there are big differences in increase or decrease and change amplitude between different land use type;The degree of land use change is deep and complex,and the degree of conversion between different types is large.(3)Through the analysis of the effecting force in the study area,this paper selected the factors which affect the land use change,and the land use situation in 2026 was predicted based on the CA-Markov model.We concluded that land use structure of study area will be changed greatly in the future,and the general trend will still perform as the great amount growth of constructive land and the obviously decrease of farmland.Then the spatial change of farmland and constructive land concentrated around the original town center,especially in places where cultivated land and construction land transfer.(4)By estimating environmental effect of study area land use system in different periods,we concluded that ecological service value function of study area land use system decreased,but the decline eased.The sensitivity index decreased,the land use gradually lost its elasticity.The contribution rate of wetland in the ecological contribution rate always has been dominant,and the ecological contribution rate of water area is also increasing gradually;the overall ecological risk index showed upward trend,but the growth trend ranged.(5)Based on prediction of study area land use change and environmental effect,this paper considered the major measures of sustainable land use in the region as below: scientific plan,strict management,strengthening the protection of waters and wetlands;building whole optimized landscape pattern;producing efficiently,improving land use performance;accelerating the transformation of the industry,introducing the market operation mechanism,creating an optimized,three-dimensional and active protection of new land use model,etc.