Study on Land Use/Cover Changes in the Inner Mongolia Autonomous Region from 1980s to 2005

In the past decades,climate change and human activities accelerated land use/land cover change and then promoted regional environmental changes in the Inner Mongolia Autonomous Region.In this article,we describe spatial and temporal characteristics and analyze driving factors of land use/land cover changes on regional and prefectural scales according to three periods of land use/land cover data,conversion rates,dynamic degree and the converted matrix.The result shows that,there are obvious regional differences and similarities in changes of land use/land cover in the Inner Mongolia Autonomous Region,which affected by topographic factors.(i) From 1980s to 2000,the main changes of land use/land cover are grassland reclamation at plain cultivation areas(94 000 hm2/a) and grassland degradation and desertification at highland steppe areas(72 000 hm2/a),which is owing to climate change,population growth and a series of political and economic macro-policy;(ii)The reclamation of cultivated land had been strongly controlled in plain cultivation areas by the "Grain for Green" policy since 2000,while the tends of grassland degradation and desertification in the banded regions at the northern edge of the plain cultivation areas(11 000 hm2/a) and highland steppe areas(133 000 hm2/a) had been increased,which is affected by the precipitation fluctuations and population growth factors.The result indicates that,plain cultivation areas become more susceptible to national macroeconomic policies,and highland steppe areas become more susceptible to changes of precipitation,which is under big pressure of economic development and population growth.These findings provide a basis for the sustainable use and the scientific management of land resources in the Inner Mongolia Autonomous Region.