土地利用动态与风力侵蚀动态对比研究——以内蒙古自治区为例

内蒙古是我国土壤风力侵蚀较为严重的地区之一,同时也是我国土地利用方式剧烈变化的地区之一。依据两期土地利用数据以及相应年代的土壤风力侵蚀数据,研究了20世纪90年代末期内蒙古自治区土地利用和风力侵蚀的静、动态格局。根据土地利用和风力侵蚀的空间分布及动态变化特点,设计了内蒙古土地利用-风力侵蚀动态区划,基于该区划详细讨论了内蒙古不同地区占主导地位的土地利用动态与风力侵蚀动态,由此揭示了两者之间存在的驱动--被驱动关系。研究发现,在20世纪90年代末期,内蒙古土地利用和风力侵蚀的基本格局没有太大变化,但风力侵蚀强度在总体上增强了;土地利用的变化主要反映为草地的退化和耕地的扩张。土地利用动态与风力侵蚀动态有着良好的时空对应关系:草地的退化与耕地的扩张导致了显著的风力侵蚀增强,而草地的改善以及耕地的收缩对风力侵蚀的影响不如前者明显,这表明了土地利用动态对风力侵蚀动态正、反向驱动的不平衡性。

Study on the Relationship Between Land-use Dynamics and Wind Erosion Dynamics in Inner Mongolia During Late 1990s

Inner Mongolia municipality,lying in the North China, is one of the zones with strong wind erosion and rapid land-use changes. It covers the grassland- cropland tran sition zone and the over-grazing grassland. The degraded grasslands, deserted croplands and dry-farming croplands of Inner Mongolia were the source regions of dust-storm which affected North and East China,Korea, Japan and America in 2000. Based on 2 sets of land-use data and the correspondent wind erosion data, the static spatial distribution and the dynamic spatial changes are outlined.According to the features of static and dynamic spatial distributions, the sub-regions of Inner Mongolia are divided. The details about the land-use dynamics and wind erosion dynamics are discussed in each specific sub-region,and the driving- droved relationship between the two dynamics is then analyzed. It can be inferred that the basic patterns of both land-use and wind erosion in Inner Mongolia did not change greatly during late 1990s. However, the main types of land-use changes are degradation of grasslands and the expansion of croplands, and the wind erosion is intensified in general. The degradation of grasslands and the expansion of croplands caused obviously intensified wind erosion, while the amendment of grasslands and the shrink of croplands affected wind erosion slightly, all of which show that there exist non -balanceable influences on wind erosion caused by different land-use change orientation.