The relationship between the characteristics of plant community and the environmental factors in the Dongkemadi River basin was studied. The results show that, the 112 vegetation plots were divided into five plant communities by TWINSPAN, and, for the compositions of species life forms, the perennial herbs (87 species) come first and annual or biennial herbs (19 species) second. The cumulative explanation percentage of the biodiversity, biomass, coverage and the environmental characteristics reaches 88.5%. The response of coverage and biomass to environmental factors is most obvious, followed by the indexes of Patrick, Shannon-Wiener and Simpson, and the response of Pielou index to environmental factors is not obvious. When the permafrost active layer is shallow, the soil nutrients such as organic matter and total nitrogen are higher, and the plant biomass, coverage, and species diversity are also larger, and vice versa. These suggest that the distribution patterns of vegetation coverage, biomass, and species diversity in the Dongkemadi River basin are caused by the integrated action of all environmental factors, of which soil organic matter and depth of active layer of permafrost are the two key environmental factors.

Download Here