【摘要】 本文从冻土与现代气候关系出发，理论上确定了冻土分区的界限。用剖面图展示出本区不同类型冻土分布的代表性高程，并以丰富的资料分析了出露在不同冻土区内的埋藏冻土层、冻土地貌假像、岛状冻土上限的起伏以及融冻地貌、植被变化等诸多现象呈现退化的一致性，得出了“退化是本区多年冻土变化的基本趋势”这一结论。更多还原

【Abstract】 The zoning boundaries of permafrost are theoretically determined from the relation between permafrost and modern climate in this paper. The boundary elevations are given in a profile. There are many phenomena demonstrating a commom degeneration such as buried frozen soil, pseudo-permafrost landforms variations of patchy permafrost table,multigelation, and vegetation changing in different regions. The important conclusion is that a basic trend of the permafrost changing in the plateau is degeneration.更多还原