Simulation Study On Land Use Change Based On CLUE-S Model

Land is the carrier of human activities,human activities and natural factors have caused land use / cover changes,but also caused a series of ecological and environmental problems,threatening the regional ecological security and land sustainable use;land use / cover Change is a complex process,and the establishment of the model is an important way to understand the causes,processes and future trends of land change,and also the core research content of land change research.China's vast territory,different regions of the natural environment and socio-economic conditions vary widely,different areas of land use conditions are also very high heterogeneity,land use heterogeneity determines the results of a region can not be arbitrarily extended to another region,and the Loess Plateau as one of the four highlands of China,land use has a higher typical,to be located in the loess plateau county as the object of study can enrich the typical regional land use / cover case study.This paper is based on Zhidan County,Yan'an City,which is located in the gully region of the Loess Plateau,the process of land change in Zhidan County from 2009 to 2016 was studied by means of GIS,gray model and ecological evaluation model,and simulated the land change in Zhidan County in 2020.The main conclusions are as follows:(1)During the period from 2009 to 2016,the land use in Zhidan County changed significantly,and the cultivated land and construction land continued to increase and the transfer of cultivated land was frequent.The study showed that the change of cultivated land and construction land was the two leading factors of land use change in the study area.(2)The change of cultivated land quantity in Zhidan County was simulated by gray model(GM)in 2009-2016,and the analog value is compared with the real value,the simulation results show that the average error of 0.1543%,It shows that the model can simulate well the number of class changes throughout the study area.(3)Select the elevation,distance from the residential area and other nine,driving factors,and the logistic regression analysis model and the regression analysis were carried out respectively,then use the ROC index to test the results,the test results show that these driving factors on the interpretation of changes in the class is excellent,the selection of driving factor is reasonable.(4)Based on the land use data of Zhidan County in 2009,the spatial distribution of land use in 2016 was simulated,and the simulation results were compared with the real data,found that the correct number of rasters accounted for 92.1% and Kappa index reached 0.905,the results show that the CLUE-S model has a good effect on the land use change in the study area,based on the data from 2016,the land use distribution in the study area in 2020 was simulated,the simulation results showed that the county and surrounding construction land grew rapidly,while the succession activities of the northeast and southwest sides of the county were more intense.(5)The landscape index analysis showed that the landscape pattern of Zhidan County showed more fragmentation,decentralization and diversification,and the high value area of landscape pattern index continued to expand,while the middle and low value areas were shrinking.The ecological effect of land use change in Zhidan County is remarkable.