Functional convergence in the decomposition of fungal necromass in soil and wood. Issue 2 (23rd December 2019)

• Record Type: Journal Article
• Authors: Maillard, François; Schilling, Jonathan; Andrews, Erin; Schreiner, Kathryn M; Kennedy, Peter
• Is Part Of: FEMS microbiology ecology. Volume 96:Issue 2(2020)
• Publication Date: 2019-12-23
• Subjects: fungi -- decomposition -- mycelial turnover -- soil -- wood -- boreal forest; Microbial ecology -- Periodicals; Microbiology -- Periodicals; 579.17
• DOI: 10.1093/femsec/fiz209
• Languages: English
• ISSNs: 0168-6496

Abstract

ABSTRACT: Understanding the post-senescent fate of fungal mycelium is critical to accurately quantifying forest carbon and nutrient cycling, but how this organic matter source decomposes in wood remains poorly studied. In this study, we compared the decomposition of dead fungal biomass (a.k.a. necromass) of two species, Mortierella elongata and Meliniomyces bicolor, in paired wood and soil plots in a boreal forest in northern Minnesota, USA. Mass loss was quantified at four time points over an 8-week incubation and the richness and composition of the fungal communities colonizing fungal necromass were characterized using high-throughput sequencing. We found that the structure of fungal decomposer communities in wood and soil differed, but, in both habitats, there was relatively rapid decay (∼30% remaining after 56 days). Mass loss was significantly faster in soil and for high-quality (i.e. high nitrogen and low melanin) fungal necromass. In both habitats, there was a clear trajectory of early colonization by opportunistic fungal taxa followed by colonization of fungi with greater enzymatic capacities to degrade more recalcitrant compounds, including white-rot and ectomycorrhizal fungi. Collectively, our results indicate that patterns emerging regarding substrate quality effects on fungal necromass decomposition in soil and leaf litter can be largely extended to fungal necromass decomposition in wood. Abstract : This study demonstrates that the decomposition dynamics of fungal mycelium in wood and soil are similar and that the initial chemical composition of mycelium is important in determining the structure of the microbial decomposer community.