新疆渭干河—库车河三角洲绿洲土地利用时空变化特征分析

Analysis on the characteristics of space-time change of landuse in the oasis on the Ugan-Kuqa River Delta,Xinjiang

基于GIS平台,以新疆各县市统计资料及Landsat TM影像解译得到的3期土地利用数据为基础,结合统计分析工作,对渭干河—库车河三角洲绿洲1996-2004年土地利用数量、类型及其变化进行了分析。分析得出,前后2个4年间,渭干河—库车河三角洲绿洲耕地为先增加后减少,园地和林地则是先减少后增加。在8年尺度上土地利用总的动态特征是,耕地、园地、林地、水域及建设用地面积增加,草地和未利用土地面积减少。8年尺度渭干河—库车河三角洲绿洲综合土地利用动态度为0.61。前4年综合土地利用动态度为0.55,耕地及建设用地的年变化率较大,园地和林地的年变化率较低。后4年渭干河—库车河三角洲绿洲综合土地利用动态度为0.38,园地与耕地的年变化率较大,水域和未利用土地的变化率较低,前4年变化程度比后4年明显。最后引入单一土地利用类型相对变化率反映出渭干河—库车河三角洲绿洲土地利用变化存在明显的区域差异。政策变动、经济发展、城市化水平、市场需求和人口增长是渭干河—库车河三角洲绿洲土地利用变化的主要原因。

Based on the GIS platform with the statistical approaches, this article analyses the landuse numbers, types and changes in the oasis on the Ugan - Kuqa River Delta during 1996-2004, using the government statistics and landsat TM data. The result of the analysis shows that, cultivated land in this oasis increased in the first half of this period, and then decreased, while the garden land and forest land have the opposite trend of change. At the 8-year scale, the overall trend of landuse in this oasis presented an increase in cultivated land, garden land, forest land, water area and construction land, and a decrease in meadowland and unoccupied land. In these 8 years, the dynamic degree of comprehensive landuse there was 0.61, while it was 0.55 in the first half and 0.38 in the second half of this period. During the first four years, the annual transformation rate of cultivated land and construction land was relatively high, while that of the garden land and forest land were relatively low. Identically, in the second four years, the annual transformation rate of garden land and cultivated land was relatively high, while that of water area and unoccupied land was relatively low. The transformation rate in the first half of this period was more evident than that in the second half. At the end, we calculate the relative transformation rate of each single land use type to analyze the special disparity of landuse change in the oasis on the Ugan-Kuqa River Delta. We believe that, some socio-economic factors, such as government policy, economic development, urbanization rate and market demand as well as population growth are the main factors which effected landuse change in the oasis on the Ugan - Kuqa River Delta.