巴丹吉林沙漠盐湖面积变化对湖泊边缘表层沉积物盐类矿物组合影响

Impacts of Salt Lakes Area Changes in BadainJaran Desert on Saline Minerals Assemblages 

中文关键词:  盐湖  盐类矿物  巴丹吉林沙漠  环境变化

英文关键词:Salt Lake  Saline minerals  BadainJaran Desert  Environmental change

中文摘要:

      选择巴丹吉林沙漠17个代表性盐湖,采集了2013年春季和秋季湖泊边缘表层沉积物样品,通过X衍射分析其盐类矿物组成和百分含量；应用Landsat 8遥感数据提取了上述两时段湖泊面积。结果发现,自春季到秋季13个面积减小的湖泊中,碳酸盐类矿物百分含量均较低,变化不明显；氯化物矿物和总盐类矿物百分含量均有增加,其增加幅度与湖泊面积变化有关。面积减少超过10%的湖泊,氯化物矿物或硫酸盐矿物百分含量总体明显增加；其余面积减少的湖泊,氯化物矿物百分含量均较春季有一定的增加,盐类矿物总百分含量也有一定程度的增加,但与湖泊面积减小程度相比没有更为明显的规律。4个面积增大的湖泊中沉积物的总盐类矿物百分含量和各盐类矿物的百分含量并未呈现显著相关性,表明在该区域湖泊面积的变化过程中,湖泊边缘表层沉积物中的盐类矿物百分含量对盐湖萎缩的指示意义相对高于湖泊扩张时期,氯化物矿物百分含量变化对湖泊面积萎缩变化响应更为敏感。

英文摘要:

      :Seventeen typical salt lakes in BadainJaran Desert were selected to the study object. Lake surface sediments samples were collected in the spring and autumn, 2013. The qualitative and semi-quantitative analyses of the mineralogical assemblages were conducted using X-ray diffraction (XRD), and area of lakes were derived from remote sense images in the spring and autumn, 2013. The results reveal that 13 of the 17 lake areas decreased from spring to autumn, and then low carbonate mineral percentage in the sediments in both periods, while the percentage of chloride mineral and total saline minerals in the sediments increased. However, area changes of four lake were significant increased, and their percentages of chloride mineral and total salt mineral in the sediments were not changed significant. Therefore, percentage of total salt mineral in the sediments could response the salt lake shrink, but not sensitively indicate lake expansion or lake area increasing. Moreover, the results suggested that percentage of chloride mineral in the lake sediments could response changes in lake areas when the lakes shrink.