Permafrost refers to all kinds of rocks and soils below zero centigrade and containing ice. Generally, it can be divided into short-term frozen soil (several hours / days to half a month), seasonal frozen soil (half a month to several months) and permafrost (also known as permafrost, which refers to the frozen soil layer that lasts for two years or more). At present, the global climate change leads to the increasingly serious degradation of frozen soil. The repeated alternation of freezing and thawing of frozen soil will cause the destruction of geological environment<br>
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