内蒙古奈曼旗农牧交错区土地利用/覆被变化的区域分异

基于内蒙古奈曼旗1975、1985、1995和2005年4期遥感影像，运用土地利用动态度、土地利用相对变化率对研究区土地利用动态变化的区域分异进行了分析，并选取多度和重要值分析了研究区土地利用/覆被变化的空间分布特征.结果表明：1975—2005年间，研究区土地利用/覆被类型趋于多样化，年变化率较大，区域分异显著.研究区北部冲积平原区以林地面积的大幅增加和沙地面积的显著减少为主要特点，其草地和沙地的变化速度最大，居民地的变化速度最小，沙地转化为耕地和沙地转化为林地这两种变化形式在该区的分布最广泛；中部沙区以沙地分布为主，各土地利用类型的变化相对较小，以耕地和沙地的互相转化为该区的主要变化形式；南部黄土区以耕地面积占绝对优势，且变化速度最小，草地和沙地的变化速度最大，该区以草地转化为耕地和草地转化为林地为主要变化形式.自然因素决定了研究区各区域土地利用结构的主体特征，人为因素决定了区域内各土地利用类型的动态变化趋势.

Regional difference of land use/cover change in farming-pasturing zone of Naiman Banner in Inner Mongolia.

Based on the four TM images of Naiman Banner in Inner Mongolia in 1975, 1985, 1995 and 2005, the extent and relative rate of land use change were used as the indices to analyze the regional difference of land use/cover change in the farming-pasturing zone of Naiman Banner, and the indices abundance and importance value were adopted to analyze the spatial distribution features of land use/cover change in the study area. The results showed that from 1975 to 2005, the types of land use/cover became diversified. The annual change rate was high, and the regional difference was significant. In the northern alluvial plain sub-area, woodland area increased rapidly and largely, while sandy land area decreased obviously. The changing speed of the areas of meadow and sandy land was the fastest, while that of residential area was the slowest. The main forms of land conversion were the conversion from sandy land to cropland and woodland. In the middle sandy land sub-area, sandy land had a wide distribution. The changes of other land use types were comparatively small, and the main form of land conversion was the inter-conversion between cropland and sandy land. In southern loess sub-area, cropland was the dominant land use type and had the smallest change, meadow and sandy land changed most quickly, and the conversion from meadow to cropland and woodland was the most important land conversion form. Natural factors determined the principal characteristics of land use structure in each sub-area of the study area, and artificial factors determined the changing trends of each land use type in each sub-area.