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Aims: This paper focuses on quantifying the distribution patterns of plant communities along the permafrost thaw depth gradient, in order to develop a framework for predicting the response of vegetation characteristics in cold high latitude ecosystems to permafrost degradation as a result of climate warming. Study area: Great Hing'an Mountains of northeastern China. Methods: Thirty plots were selected in a west slope region of the Great Hing'an Mountain Valleys to study the relationship between the depth of the active layer of permafrost and characteristics of plant communities. Results: The distribution of plant communities strongly correlated with the permafrost thaw depth. With increasing depth of the active layer, important species showed an obvious transition and plant strategies shifted gradually from helophilous to hygrophilous to mesophilous. Both biodiversity and the total biomass of understory vegetation decreased significantly along this gradient. Conclusions: The response of the vegetation characteristics varied considerably with the depth of the active layer throughout the permafrost degradation. Our results show implications for vegetation in the face of climate change as rising temperatures directly affect permafrost, and in many areas the depth of the active layer is increasing.

来源平台：PHYTOCOENOLOGIA