帕米尔高原东部表层沉积物粒度特征及其迁移路径

Grain Size Characteristics and Transport Pathways of Surface Sediments in Eastern Pamir Plateau

[目的]研究帕米尔高原东部表层沉积物粒度特征及来源,为提高中国西部高原地区沉积环境认知及生态环境建设提供科学依据。[方法]利用激光粒度仪对帕米尔高原东部表层沉积物粒度进行分析,并通过后向轨迹模型探讨远源风成沉降对其表层沉积物组成的影响。[结果]研究区表层沉积物以砂粒为主,表层沉积物粒径随海拔的逐渐升高而减小。初步推测表层沉积物主要为湖相沉积,远源风成沉降主要受中亚西风气流和塔克拉玛干沙漠西侧沙尘颗粒物影响。[结论]帕米尔高原东部处于生态环境脆弱区,应因地制宜制定土地利用规划,同时需防范中亚沙尘颗粒对其生态环境的影响。

[Objective]The grain size characteristics and sources of surface sediments in the Eastern Pamir Plateau were analyzed in order to provide a scientific basis for improving the understanding of the sedimentary environment and ecological environment construction in the western plateau of China.[Methods]The particle size characteristics of surface sediments in the Eastern Pamir Plateau were analyzed using a laser particle size analyzer.The influence of remote aeolian sedimentation on the composition of surface sediments was analyzed by use of a backward trajectory model.[Results]The surface sediments in the study area were mainly sand particles.Particle size of the surface sediments decreased with the gradual increase of altitude.It was preliminarily speculated that the surface sediments were mainly lacustrine sediments,and the far-source aeolian settlement was mainly affected by westerly air flow in Central Asia and sand dust particles in the Western Taklimakan Desert.[Conclusion]The Eastern Pamir Plateau is located in a fragile ecological environmental area.Land use planning should be formulated according to local conditions.At the same time,it is necessary to prevent the impact of dust particles on the ecological environment of Central Asia.