Structural and functional microbial diversity in deadwood respond to decomposition dynamics

Abstract

We investigated the changes in microbial community diversities and functions in natural downed wood at different decay stages in a natural oak forest in the Italian Alps, through metagenomics analysis and in vitro analysis. Alfa diversity of bacterial communities was affected by the decay stage and log characteristics, while beta diversity was mainly driven by log diameter. Fungal and archaeal beta diversities were affected by the size of the sampled wood (log diameter), although, fungi were prominently driven by wood decay stage. The analysis of genes targeting cell wall degradation revealed higher abundances of cellulose and pectin‐degrading enzymes in bacteria, while in fungi the enzymes targeting cellulose and hemicellulose were more abundant. The decay class affected the abundance of single enzymes, revealing a shift in complex hydrocarbons degradation pathways along the decay process. Moreover, we found that the genes related to Coenzyme M biosynthesis to be the most abundant especially at early stages of wood decomposition while the overall methanogenesis did not seem to be influenced by the decay stage. Intra‐ and inter‐kingdom interactions between bacteria and fungi revealed complex pattern of community structure in response to decay stage possibly reflecting both direct and indirect interactions.

Changes and driving factors of microbial community composition and functional groups during the decomposition of Pinus massoniana deadwood

“…For example, Yuan et al (2017) show that tree species were the main source of fungal community diversity at different decomposition stages, and fungal communities achieved the highest levels of diversity at the intermediate and late decomposition stages. Pioli et al (2023) find that the α diversity of the bacterial community was primarily linked to the decomposition stages of the tree. Qi et al (2023) observe the similarities in the microbial community structure and function between the early and late decomposition stages of deadwood, but differences in the middle stages.…”

“…Pioli et al. ( 2023 ) find that the α diversity of the bacterial community was primarily linked to the decomposition stages of the tree. Qi et al.…”