中文摘要：

通过对毛布拉格孔兑流域的地表积物的粒度、化学元素的空间分布的分析,得出的结论：毛布拉格孔兑河流附近沙物质组成表现为风成特性;不同河段沉积物平均粒度参数、化学元素的分布具有一定相似性,且元素之间存在高度的相关性,表明其具有相似的沉积环境;不同河段A-CN-K图解揭示了毛布拉格孔兑不同河段地表物质化学风化程度均很低,处于较弱的去Na、Ca阶段;不同地貌单元沉积物粒度组成、地球化学过程表现出一定的递变规律,可能物源有关;毛布拉格孔兑平均粒径与元素的含量存在较好的相关性,说明粒径大小与化学风化程度有一定关系;总之,在不同空间尺度上,毛布拉格孔兑地表沉积物理化特征的分异实质上反映风动力和水动力的差异性分选,即沉积物对风、水交互作用的响应。这对于构建风水两相沉积物综合判别指标等问题有着重要的意义。

英文摘要：

In this paper, field survey, measurement and sampling were conducted in the transition zone between river and desert on the Mu Bulag River, Inner Mongolia, China. A total of 142 samples of surface sediments from different river sections were analyzed in the lab to analyze the Mu Bulag River＇s granularity, spatial distribution of the geochemical elements of the near-surface sediments. The granularity composition of Mu Bulag River＇s surface sediments are fine sands;Si and Al take up a large part of chemical composition;The characteristic of chemical elements and granularity composition of the near-surface sediments from different sections are similar, and a clear relationship occurs between them, indicating that one major source of the Mu Bulag River sediments may originate from its south loess hilly area;The CIA of the Mu Bulag River basins is below 50, and the A-CN-K ternary diagram shows that a weak chemical weathering by loss of Na and K occurred in these sediments, while other geochemical elements are in a less weathering or leaching process. The difference of the chemical weathering degree of different sections is closely related to its local climate and landform pattern;when different geomorphic units are under the same section, the granularity characteristic and chemical weathering degree have a corresponding grading law from nearby to far apart from the riverbed;The average grain size of Mu Bulag River is correlated with some elements, and it shows that particle size affects the processes of chemical weathering to a certain extent. In short, in the different spatial scales, the differentiation about the physical weathering characteristic of the sediment surface of Mu Bulag River essentially reflects the different separation of wind power and water power. Those preliminary results have important significance for developing a comprehensive index to distinguish the interaction between aeolian and fluvial processes.