Objective  The species composition of forest community in Changbai Mountain Nature Reserve of northeastern China and its relationship with environmental factors were analyzed by the method of quantitative ecology, providing scientific basis for protection and sustainable management of forest ecosystems in the region, and providing references for similar researches.

  Method  With the help of remote sensing data, a total of 40 sample points were selected from 750 m to 1 850 m above sea level in the Changbai Mountain Nature Reserve in different slope aspects along roads, and community surveys were carried out from August to September 2021. Based on the survey data, the importance values of different species in the sample plots were calculated. Then the two-way indicator species analysis (TWINSPAN) and detrended correspondence analysis (DCA) were used to divide the sample plots into different community types. Finally, combining with environmental data, the canonical correspondence analysis (CCA) and variation partitioning were used to explore relationships between the distribution of communities and environmental factors.

  Result  (1) According to the results of TWINSPAN and DCA, the 40 sample plots were classified into 9 community types. (2) The CCA ranking results well reflected the relationship between community distribution and environmental factors. Among the 10 selected environmental factors, altitude, slope, annual mean temperature, isothermality, temperature seasonality, mean diurnal range, annual precipitation, precipitation seasonality, temperature annual range had greater impacts on species distribution. (3) The results of variational partitioning showed that these 10 tested factors could explain 46.8% variation of species distribution. Among these factors, topography, climate and their interaction respectively accounted for 8.0%, 29.1% and 9.7% of the variation, while 53.2% of the variation was unexplained.

  Conclusion  The investigated area in Changbai Mountain mainly includes 9 types of forest communities, and the alteration of hydrothermal conditions caused by altitude is the main environmental factor affecting community distribution. The unexplained part is concerned to be associated with the complexity of community composition as well as the lack of environmental information such as soil properties etc.