毛乌素沙地晚第四纪地层特征与沙漠化研究综述

发布时间：2018-11-26 15:10

【摘要】：毛乌素沙地保存着晚第四纪以来的多种沉积序列,记录了过去数十万年以来的古气候变化信息。其在地层发育上过渡性明显,以神木、榆林、横山、靖边及定边一线的沙漠-黄土边界带最为典型,主要有风成沉积和河湖相沉积2种类型,其中古风成砂是这2类沉积剖面的典型地层特征。随着地层记录、精确测年技术等现代沉积学方法的进步以及与历史地理、环境考古、遥感技术相结合的综合研究,晚第四纪以来毛乌素沙地的沙漠演变研究精度不断提高,毛乌素沙地进退在不同的时空尺度下与冷暖期的多旋回变化相适应,经历了沙丘固定与活化的多次转变。毛乌素沙地沙漠化研究在指标运用上多直接沿用黄土区的环境代用指标,有必要建立适合沙漠-黄土过渡地区的环境代用指标,且将气候环境物理替代性指标与元素地球化学以及生物学指标相结合。毛乌素沙地内部沉积速率快、受人类活动干扰较小的湖泊沉积物,对于提高沉积物的分辨率、恢复短时间尺度的环境变化过程也具有显著优势。
[Abstract]:The Maowusu sandy land preserves a variety of sedimentary sequences since the late Quaternary and records paleoclimate change information over the past several hundred thousand years. The transition in stratigraphic development is obvious, with the typical desert-loess boundary zone along the lines of Shenmu, Yulin, Hengshan, Jingbian and Dingbian. There are mainly two types of aeolian deposits and fluvial and lacustrine facies deposits. Paleo-aeolian sand is a typical stratigraphic feature of these two types of sedimentary profiles. With the progress of modern sedimentological methods, such as stratigraphic records, accurate dating techniques, and comprehensive research combined with historical geography, environmental archaeology and remote sensing techniques, the research accuracy of desert evolution in Maowusu sandy land has been continuously improved since the late Quaternary. The advance and retreat of Maowusu sandy land at different space-time scales are adapted to the polycyclic changes in cold and warm periods, and have undergone many changes of sand dune fixation and activation. In the study of desertification in Maowusu sandy land, the environmental substitute index of loess region is used directly in the application of indicators. It is necessary to establish the environmental substitute index suitable for the desert loess transition area. The physical substitution index of climate and environment is combined with element geochemistry and biological index. The lake sediments in Maowusu sandy land with high deposition rate and less interference from human activities also have significant advantages in improving the resolution of sediments and restoring the process of environmental change on a short scale.
【作者单位】：平顶山学院旅游与规划学院;陕西师范大学旅游与环境学院;平顶山学院化学与环境工程学院;
【基金】：国家自然科学基金国际合作项目(41210002) 平顶山学院高层次人才资助项目(PXY-BSQD-2017004) 河南省高等学校青年骨干教师资助计划(2014GGJS-141)
【分类号】：P534.63;X171.1

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