Land use change and its driving forces in Zhanggutai district of south Horqin Sandy Land based on remote sensing and GIS

By using remote sensing images,GIS technology,and mathematical statistic methods,this paper analyzed the past 20 years' land use change and its driving forces in Zhanggutai district of Liaoning Province,China.In the period of 1988-2009,cultivated land and forestland were the main land use types in the district.Across this period,the areas of forestland,cultivated land,and construction land increased,while those of grassland,water body,and unused land decreased.The annual change rates of grassland,construction land,and unused land were higher than those of other land use types.The comprehensive index of land use degree increased from 235.34 in 1988 to 251.65 in 2009.The conversion between land use types was mainly characterized by the conversion from grassland and unused land to forestland and cultivated land and that between cultivated land and forestland,accounting for 95.58% of the total conversed area.These land use changes were driven by the combined effects of population,policy,and environmental conditions,among which,population growth and policy guidance played critical roles in intensifying these changes at 20-year time scale.