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以河西地区为研究区,采用1975年MSS影像及1990年、2000年、2007年的TM和ETM+影像为数据源,提取了4期盐碱地现状信息和3期盐碱地时空变化信息,对研究区近30年来的盐碱地现状与动态变化进行统计与分析。研究结果表明:1)盐碱地总面积整体上经历了先增加后减少的趋势,2000年其分布面积达到峰值,为10554.28km2。2)盐碱地在1990年到2000年间急剧扩张,2007年盐碱地面积与2000年时相比虽然有所减少,但相比1975年还是有大幅扩张。3)气候、地形地貌和水文因素是河西地区盐碱地分布格局形成的重要因素,人类活动是近30年来盐碱地变化的主要驱动力。
Taking Hexi area as the research area and the TMS and ETM + images of 1975 and 1990, 2000 and 2007 as the data source, the status quo information of the four saline-alkali lands and the spatio-temporal changes of the three saline-alkali lands were extracted. The status and dynamic changes of saline land over the past years have been statistically analyzed. The results showed as follows: 1) The total area of saline-alkali land increased firstly and then decreased, and its distribution area peaked at 10554.28km2.2 in 2000.) The saline-alkali soil expanded sharply from 1990 to 2000. The area of saline- Compared with the number of years, although it has decreased, but compared to 1975 there is still a substantial expansion. 3) Climatic, topographic and hydrological factors are important factors in the distribution pattern of saline-alkali soil in Hexi area. Human activities are the main driving forces for the change of saline-alkali soil in recent 30 years.