塔里木盆地地貌过程对绿洲形成演变的影响  

Influence of Geomorphologic Processes on Formation and Evolution of the Oases in the Tarim Basin,Xinjiang

作　　者：杨发相[1] 

机构地区：[1]中国科学院新疆生态与地理研究所,乌鲁木齐830011

出　　处：《干旱区地理》2003年第4期361-366,共6页Arid Land Geography

基　　金：国家重大基础研究项目 (G19990 43 5 0 2 );KZCX -XJ0 1-0 2课题资助

摘　　要：第三纪末以来 ,天山、昆仑山强烈隆起使塔里木盆地相对下沉 ,山盆高差悬殊大 ,自山顶至盆地腹部地貌外力作用过程依次由冰川作用→冰缘作用→流水作用→干燥作用→冲 -洪积作用→湖积作用→风沙作用过渡。在山区河谷平原、平原区冲积扇、冲积平原、湖积平原等地方形成条带状、串珠状、扇形状绿洲 ,绿洲平面几何形状与适宜绿洲形成与发展的地貌类型空间分布基本吻合。绿洲荒漠化和荒漠绿洲化与地貌过程的关系密切。纵观区内地貌过程发展趋势可预测 ,区内流水、风沙和人类活动三大地貌过程将有增无减 ,流水侵蚀与风蚀风积作用将对绿洲产生不良作用 ,山区流水侵蚀过程加强导致山麓地带绿洲山洪泥石流危害加重 ,平原河流下游地区流水作用减弱 ,风蚀风积过程加剧 ,由绿洲→荒漠演变 ,而人类活动可分建设作用与破坏作用两方面 ,前者可稳定绿洲乃至促进荒漠绿洲化而后者则导致绿洲荒漠化。因此 ,改善山区、山麓地带 ,特别是盆地南缘与塔河中、下游等重要地区地貌过程并防止绿洲荒漠化 ,是保障区域可持续发展的有效途径。Tarim Basin is the largest interior basin in China. Since the end of Tertiary, the violent uplift of the Tianshan Mountains and Kunlun Mountain has brought about a subsidence of the Tarim Basin, and the height difference between the mountains and the basin is great. From the alpine zones to the hinterland of the basin, the geomorphologic exogenic force action is in a devolution of glaciation → periglacial cold action → fluviatile action → arid action → alluvial dilluvial action → lacustrine action → sand drift action. The corridor shaped, bead string shaped or fan shaped oases form in the mountainous valley plains, alluvial fans on the plains, alluvial plains, lacustrine plains, etc. The shapes of the oases accord basically with the spatial distribution of the geomorphologic types befitting to form and develop oases. The temporal and spatial change and the rise and decline of the oases are caused 4 kinds of geomorphologic processes, i.e., the neotectonic movement, fluviatile action, wind erosion and human activities. The main aspects are as follows: (1) The neotectonic movement results in the uplift of the alluvial fans in the piedmont zones, deep cut or course change of the streams, and desertification of the oases. (2) The oases are damaged by lateral fluviatile erosion, floods and debris flows, and the evolution of the oases is caused by the course change of the streams and the cut off of the stream flow. (3) The desertification of the oases is aggravated by wind erosion and sedimentation. (4) The artificial geomorphologic processes make the enlargement of the artificial oases or the desertification of the natural oases. Desertification of the oases and the reverse of the deserts to oases are closely related to the geomorphologic processes. Making a comprehensive view on the developing trend of the geomorphologic processes in this region, it can be predicted that the three main geomorphologic processes, i.e., fluviatile action, wind erosion and human activities, will be increased. The fluviat

关 键 词：地貌过程 绿洲形成演变 塔里木盆地 流水 风沙 人类活动 

分 类 号：P931[天文地球—自然地理学]