Vegetation community classification of the Sanzai area in Mongolia

This study reports the forest vegetation community classification of the Sanzai area (Khentii range) in Mongolia using the phytosociological method. The forest vegetation has been classified into five major types characterized by the following associations: Larix sibirica community, Pinus sylvestris community, Betula fusca-Picea obovata community, Betula platyphylla community, and Pinus sibirica community. Ecological characteristics such as species composition, layer structure, vegetation ratio, and the distribution of individual trees based on their diameter at breast height (DBH) are slightly different among the plant communities. In all communities, the significant value was highest in the Larix sibirica with 74.6%, followed by Pinus sibirica (64.2%), Betula platyphylla (59.5%), Pinus sylvestris (53.9%), and Picea obovata (47.7%). Our results of DBH analysis show that the size-frequency distribution of Pinus sylvestris, Pinus sibirica, Larix sibirica, and Picea obovata was a binomial distribution in all the communities, suggesting that for the time being, these species dominate continuously. In addition, it is likely that Betula platyphylla will dominate rapidly because of its higher frequency of young individuals. This indicates the forest condition impairment in the forest of the Sanzai area.