MULTIVARIATE ANALYSIS OF PLANT COMMUNITIES AND PERMAFROST ENVIRONMENT AFTER THE DISASTROUS FIRE IN AMUER FOREST LAND
林区火灾后植物群落与冻土环境的多元分析

The plant communities after the 1987's turbulent forest fire in Amuer forest land of Mt. Daxinganling were studied by using the methods of TWI-NSPAN polythetic hierarchical divisive classification (TWINSPAN program) and DCA ordination(DECORANA program). By multiple regression analysis to interprete of the DCA ordination axis on permafrost environment factors, we conclude that DCA axis 1 reflects the gradient of soil characteristics and topography which determine the distribution of plant communities, DCA axis 2 is interpreted as the gradient of forest fire intensity, and it can causes changes of the depth to frozen soil and the shallow soil temperature of surface layer which are the significant factors for the distribution of plant communities. Furthermore, we used the correlation and regression method in analysing the relationship between DCA axis 2 and permafrost environment factors, and as a result, a regression equation was produced. We also discussed the directions and stages of plant secondary succession under the influence of permafrost environment development based on the results of the above analysies.