Fungi are key organisms in terrestrial ecosystems, functioning as decomposers, pathogens, and symbionts. Identifying the mechanisms that underlie their distributions and the processes that structure their communities is likely to be critical for predicting how ecosystems will respond to global environmental change. 

Researchers from Xishuangbanna Tropical Botanical Garden (XTBG) used the Elements of Metacommunity Structure (EMS, combining coherence, range turnover and range boundary clumping) to identify and describe patterns of fungal metacommunity structure. 

They selected 22 karst forest sites covering a wide range of environmental conditions (elevation, slope, aspect, soil) for soil fungi inventory across Yunnan province. They also sampled 22 nearest non-karst forest sites at similar altitudes and latitudes to the karst sites. 

They found that the karst and non-karst forest soils had distinct fungal communities, and those compositional patterns were consistent across different fungal taxonomic and functional groups. 

The strong differences in community composition between karst and non-karst sites suggested that variability in environmental conditions (e.g. soil pH, temperature, precipitation) drive differences in fungal community assembly. 

They further found that soil fungal metacommunities in Yunnan responded to the same latent environmental gradient, with species distributions forming a coherent structure, indicating that species occurrences with respect to the dominant environmental gradient are non-random. 

"Our study demonstrates the utility of DNA metabarcodes for investigating phylogenetically diverse tropical and subtropical fungal communities and the need for more studies in these important but less studied biomes," said Dr. Kingsly C.Beng, the first author of the study. 

The study entitled "Identifying the mechanisms that shape fungal community and metacommunity patterns in Yunnan, China" has been published in Fungal Ecology.