[Environmental Filters Drive the Assembly of the Soil Fungal Community in the Larix principis-rupprechtii Forests of the Guandi Mountains].

Abstract

The community assembly process, which purports that the trade-off between the stochastic process and the deterministic process, is the central issue of community ecology, and is one of the most controversial ecological issues. The current research investigated the fungal community in the Larix principis-rupprechtii forests of the Guandi Mountains and elucidated the relative role of the stochastic and deterministic processes in the assembly of soil fungal community on a local scale. The correlation analysis and redundancy analysis of the physicochemical factors in soil and dominant fungal phyla, as well as the structural equation model analysis, showed that these physicochemical factors and aboveground vegetation diversity had significant effects on fungal communities. The direct effect of vegetation diversity on fungal community structure was the most (1.1858). It is inferred that the determination process (environmental selection) has a certain influence on the assembly of fungal communities. The β-diversity of fungal community shows a distance-decay pattern; thus, it can be concluded that the stochastic process (dispersal limitation) has a certain effect on the assembly of fungal communities. Null model analysis confirmed that the deterministic process was the main driving factor for the assembly of the fungal communities in the study area, and their relative importance varied along with altitudinal gradient. The null deviations in the study area were negative, suggesting that habitat filtering was the driving factor of the assembly of fungal communities. Overall, the deterministic versus stochastic processes jointly drive the assembly of fungal communities in the study area, while the deterministic processes triumph.