青藏高原自然地理研究的进展

RECENT PROGRESS OF GEOGRAPHICAL STUDIES ON THE QINGHAI-XIZANG PLATEAU

本文综述青藏高原自然地理研究所取得的主要进展,诸如晚新生代以来高原剧烈抬升引起的自然环境巨大变化,上新世的古地理环境和高原隆起,湖泊和水系的演变,第四纪冰川作用,全新世古地理环境演化以及高原隆起对自然环境和过程的影响等。指出了青藏高原具有的独特自然环境类型和特征,阐述了山地垂直自然带谱类型的比较研究,三维空间的地域分异,自然区划以及对独特地生态现象和区域的研究成果。

Based on the research results of geographical studies of the Qinghai-Xizang Plateau in the last two decades, the main progress of studies on the paleogeographical evolution, natural environment and its regional differentiation, as well as environmental problems are dealt with in the present paper. The altitude of the Plateau surface remained generally at a mean elevation of 1000 m asl until the occurence of intense uplifting between the end of Pliocene and beginning of Early Pleistocene, A total uplifting magnitude of 3500m, with differentiations in space and stages, has been attained over most parts of the Plateau since Quaternary. The intense uplifting of the Plateau has given rise to enormous changes of the natural environment since Late Cenozoic, such as the evolution of lakes and drainage systems, the Quaternary glaciation, the paleogeographical evolution in the Holocene and the influence of uplifting of the plateau on natural environments and processes. Characterized by the most outstanding features of natural environment the Qinghai-Xizang Plateau differs to a great extent from the Eastern Monsoon Realm and the Northwest Arid Realm in China. According to comparative studies of the altitudinal belt, two systems of the structure-type of the altitudinal belt may be identified: the monsoonal and the continental. From a point of view of three dimensional zonation, the spatial differentiations of the Plateau are explained and a tentative scheme of physico-geographical regionalization has been proposed. A number of gee-ecological phenomena, such as the vapour channel, dry valley and the cold-arid core area are discussed in the present paper.