Responses of fungal communities along a chronosequence succession insoils of a tailing dam with reclamation by Heteropogon contortus

Phytoremediation can obviously change the fungal communities in the soils, which will significantly impactcarbon (C) and nitrogen (N) cycling in ecological system. So far, the relationship between soil fungal communities and environmental factors is still poorly understood along a long chronosequence. In this study, fungalcommunities in the surface and rhizosphere soils of a tailing dam with Heteropogon contortus phytoremediationwere investigated to explore the evolution of fungal community in a span of 50 years. The results showed thatmicrobial community diversity increases along with time series of Heteropogon contortus phytoremediation. Thedominant Dothideomycetes (20.86%), Agaricomycetes (18.09%), and Arthoniomycetes (1.69%) in rhizosphere soilswere relatively higher than those in topsoil (13.9%, 2.65%, and 0.20%) at class level. Spearman correctionanalysis by phylum level was conducted to detect whether microflora was related to soil Physico-chemicalproperties, which affecting the composition of fungal communities along with the Heteropogon contortus phytoremediation. The nitrogen cycle indicators represented good linear correlations as chronosequence goes on, theindexes in the rhizosphere soil were much higher than those in the surface soils and the highest level hasoccurred in the 47-year-old Heteropogon contortus phytoremediation. The relative abundance of plant pathogen,wood saprotroph, dung saprotroph, and Arbuscular Mycorrhizal showed an upward tendency in rhizosphere soilsalong with the Heteropogon contortus phytoremediation. The highest soil fungal communities abundance anddiversity were possibly attributed to the high-quality Heteropogon contortus litter returning to the ground andartificial disturbance treatments. Such changes in soil fungal communities might demonstrate a significant stepforward and provided theoretical support for the biological governance of Heteropogon contortus phytoremediation in 50 years. Our study provides an insight on microbial communities connecting with soil C, N, P andS cycles and community functions in a complex plant-fungal-soil system along a long chronosequence in minemicro-ecology.