The Research Of Regional Karst Land System Evolution Mechanism And Trend Simulation In Du’an,Guangxi

With the rapid development of national economy, populationexplosion and the acceleration of urbanization, the activities of land useare more and more frequent, and the evolution of land system is alsomore and more drastic. The alarm bell rings for human by soil erosion,land degradation, deteriorating ecological environment, the sharpdecreasing of the total amount of cultivated land and the frequent naturaldisasters.Du’an locates in a typical Karst region. The serious degradation ofecosystem, especially the quickly spread of land rocky desertificationrestricts the development of local economy and threatens the livingenvironment of native people. Although the government adopts a series ofmeasures to control desertification, the “Population—Land—Environment” problem still stands out in Du’an. To systematically masterthe land use and to understand the future development trend,this thesisanalyzes the evolution mechanism of Karst land system in Du’an andimitates the evolution trend. The main research work includes:(1) Obtain land use information by interpreting with1988,1999and 2005remote sensing images.(2) Select the speed of land use structure changes,contribution rate,intensity index and land use dynamic degree of land type,calculate1988-1999-2005year land use structure change table, and then analyzethe number of land use structure change.(3) Analyze the change of land use spatial pattern by using landscapepattern index.(4) Based on the analysis of evolution mechanism, imitate theevolution trend taken advantage of “BP-ANN-CA” model, and thenobtain the situation of land use in2015.(5)Compare the situation of land use in2015with the land useamong1988,1999and2005，and provide corresponding countermeasuresand suggestion.