Abstract:

Wood-decaying fungi have rich species diversity and play an important role in the decomposition of fallen wood in forest ecosystems. Conifer trees are dominant in the forest ecosystems of the Greater and Lesser Khinggan Mountains. Therefore, it is necessary to determine wood-decaying fungal species diversity in conifers and which factors influence their distribution in order to understand substance cycling in the forest ecosystems of the Greater and Lesser Khinggan Mountains. Over 16 years, 1,561 samples of wood-decaying fungi were collected from conifer trees (including Larix, Pinus, Abies and Picea) in the Greater and Lesser Khinggan Mountains. The host and fungal species and their rotting types were recorded, and the relationship between the fungal species distribution and potential influencing factors was analyzed. The results showed that there were 166 species belonging to 70 fungal genera found in the conifer wood of the Greater and Lesser Khinggan Mountains. This included 111 white-rot species (66.9%) and 55 brown-rot species (33.1%). Among the 166 fungal species, 19 species (11.5%) grew on all conifers. In the Greater Khinggan Mountains, larch was the dominant host, with the highest number of species and individuals of wood-decaying fungi found there. In contrast, pine was the dominant host in the Lesser Khinggan Mountains. This study of six typical sites showed that the biodiversity of wood-decaying fungi was higher in the Lesser Khinggan Mountains than the Greater Khinggan Mountains, with only 11 species occurring in all six sites. Further, the tree species had greater influence on the distribution of wood-decaying fungi than the site locations.

Key words: wood-decaying fungi, diversity, conifers, the Greater and Lesser Khinggan Mountains