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以开都河流域下游绿洲为研究区,以1973年MSS、1990年TM、2010年ETM+影像和统计资料为基本数据源,运用RS与GIS技术对研究区土壤盐渍化的类型、程度、面积与空间分布信息进行提取,利用土地转移矩阵和盐渍化动态度模型对近40a研究区土壤盐渍化时空动态变化及其成因进行分析。研究结果表明:1)1973年土壤盐渍化面积为1293.14km2,2010年为659.68km2,减少633.46km2;其中重度盐渍化面积减少150.69km2,中度盐渍化面积减少370.56km2,轻度盐渍化面积减少112.21km2,均呈现下降趋势。2)1973～2010年,重度、中度、轻度土壤盐渍化向绿洲边缘移动;重度、中度、轻度盐渍化地之间相互转化,荒地是三类盐渍化地转入面积的主要部分。3)大陆荒漠性气候、成土母质富含硫酸盐和氯化物、低洼的地形、地下水位浅等自然因素是该区域土壤盐渍化发生演变的内因;大规模的绿洲土地开发利用和不合理的农业灌溉模式等人类经济活动是其发生演变的外因。
Taking the oasis in the lower reaches of the Kaidu basin as the research area, the types, degree and area of soil salinization in the study area were studied using the MSS in 1973, the TM in 1990, the ETM + images in 2010 and the statistical data in 2010 as the basic data sources. And the spatial distribution information were extracted. The temporal and spatial changes of soil salinization and their genesis in the past 40 years were analyzed by using land transfer matrix and salinization dynamic model. The results show that: 1) the area of soil salinization is 1293.14km2 in 1973, 659.68km2 in 2010, decreasing 633.46km2; the area of severe salinization is reduced by 150.69km2; the area of moderate salinization is reduced by 370.56km2; The area of stains decreased by 112.21km2, showing a downward trend. 2) From 1973 to 2010, severe, moderate and mild soil salinization moved to the edge of oasis; heavy, moderate and mild salinization transformed into each other, and the wasteland was transformed into three areas of salinization The main part. 3) Due to the desert climate in China, natural elements such as sulphate and chloride are rich in sulphate and chlorophyll, the low-lying topography and shallow groundwater level are the internal causes of the evolution of soil salinization in this area. The development and utilization of large-scale oasis land are irrational Human economic activities such as agricultural irrigation patterns are the external causes of their evolution.