基于通径分析的酒金盆地绿洲化时空变化及影响因子研究

基于Landsat遥感影像和社会经济数据等,重建1963~2009年间西北干旱区酒泉金塔盆地(酒金盆地)绿洲空间分布图,采用转移矩阵、绿洲动态度和通径分析法等开展酒金盆地绿洲时空变化过程的区域差异和影响因子差异研究。结果表明：近50 a来,酒金盆地绿洲面积呈现增加趋势,表现为酒泉绿洲连续增长和金塔绿洲的波动式增长。酒泉绿洲扩张主要表现为绿洲边缘区的外延扩张,金塔绿洲主要表现为绿洲边缘区和季节性河道两侧绿洲波动变化。酒泉绿洲稳定性较金塔绿洲的高,水资源的持续供给与否决定着绿洲边缘稳定的关键,尤其在金塔绿洲。人类活动的区域差异和政策响应程度及经济水平的差异是造成2个绿洲时空变化差异的内在影响因子。

Spatiotemporal Change of Jiuquan-Jinta Basin Oasis and Its Impact Factors Based on Path Analysis

Based on the landsat images and social economical data, the oasis distribution map in 1963-2009 were reconstructed via GIS technology, path analysis, transfer matrix and correlation analysis were used to explore the differences of spatiotemporal change and its impact factors of Jiuquan-Jinta Basin in NW China. In this study, the land covers were divided into two categories: oasis and desert. And the oasis included farmland, woodland, grassland, water and residential area which based on classification criteria; the other one are desert. The results showed that: 1) The oasis area increased gradually from 1 189.04 km² in 1963 to 1 678.99 km² in 2009, Jiuquan Oasis increased in its edge area with a relatively stable upward trend, while Jinta Oasis increased in its fringes and both sides of the seasonal river with a fluctuation way. 2) The stability of Jiuquan Oasis is higher than that of Jinta Oasis, the stability of the oasis were determined mostly by the sustainable supply degree of water resource, especially in Jinta Oasis. Regional difference on human activities, the degree of the responding rate to policy, and the economic and development level were the main factors which affected the spatiotemporal change between Jiuquan and Jinta Oasis.