Successional development of wood-inhabiting fungi associated with dominant tree species in a natural temperate floodplain forest

Abstract

Fungi play a crucial role in dead wood decay, being the major decomposers of wood and affecting microbiota associated with dead wood. We sampled dead wood from five deciduous tree species over more than forty years of decay in a natural European floodplain forest with high tree species diversity. While the assembly of dead wood fungal communities shows a high level of stochasticity, it also indicates clear successional patterns, with fungal taxa either specific for early or late stages of wood decay. No clear patterns of fungal biomass content over time were observed. Out of 220 major fungal operational taxonomic units, less than 8% were associated with a single tree species, most of them with Quercus robur . Tree species and wood chemistry, particularly pH, were the most important drivers of fungal community composition. This study highlights the importance of dead wood and tree species diversity for preserving the biodiversity of fungi. • Tree species-rich floodplain forest shows high diversity of wood fungi on dead wood. • Most fungi show low specificity and inhabit wood of multiple hardwood tree species. • Tree species-specific fungi are more abundant in early and late decomposition stages. • Fungal communities of deadwood are most affected by tree species and wood chemistry. • Fungal community assembly is largely stochastic but shows tractable succession.