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出 处:《冰川冻土》1996年第S1期174-180,共7页Journal of Glaciology and Geocryology
摘 要:论证了东北地区多年冻土退化的速度,在南部快于北部,阳坡快于阴坡,先山区后谷地,城镇大于田野,人为影响大于自然因素等诸方面的规律。多年冻土完全退化消失后有利于农业生产、育林更新;有利于采金和建筑开挖,使水力循环加快。但多年冻土退化过程中威胁建筑物的安全与稳定,造成热融等许多危害,易引起地下水的污染,应当密切注意防范。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.
分 类 号:P642.14[天文地球—工程地质学]
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