A Preliminary Analysis on the Regularity of Permafrost Degradation, its Advantages and Disadvantages in the Greater and Lesser Xing'an Mountains
Wang Chunhe, Zhang Baolin and Liu Futao(Changchun Institute of Geography, Chinese Academy of Sciences, 130021)
This paper demonstrates in detail the regularities of that the permafrost degradation speed of northeast China is faster in the southern part than in the northern part of the region, in the south slopes than in the north slopes, in the towns than in the fields, by the artificial effects than by the natural factors. The permafrost degradation occurs first in hills, then in valleys. The complete degradation and disappearance of permafrost are advantageous to the agricultural production, tree planting and regeneration, gold mining, construction and speeding up the water circulation. Nevertheless, the permafrost degradation processes imperil the buildings. It causes a lot of problems, such as thermal thawing, the pollution of underground water, to which should be paid more attention.