Linking molecular deadwood-inhabiting fungal diversity and community dynamics to ecosystem functions and processes in Central European forests

Abstract

Fungi play vital roles in the decomposition of deadwood due to their secretion of various enzymes that break down plant cell-wall complexes. The compositions of woodinhabiting fungal (WIF) communities change over the course of the decomposition process as the remaining mass of wood decreases and both abiotic and biotic conditions of the wood significantly change. It is currently not resolved which substrate-related factors govern these changes in WIF communities and whether such changes influence the deadwood decomposition rate. Here we report a study on fungal richness and community structure in deadwood of Norway spruce and European beech in temperate forest ecosystems using 454 pyrosequencing. Our aims were to disentangle the factors that correspond to WIF community composition and to investigate the links between fungal richness, taxonomically-resolved fungal identity, and microbial-mediated ecosystem functions and processes by analyzing physico-chemical wood properties, lignin-modifying enzyme activities and wood decomposition rates. Unlike fungal richness, we found significant differences in community structure between deadwood of different tree species. The composition of WIF communities was related to the physico-chemical properties of the deadwood substrates. Decomposition rates and the activities of ligninmodifying enzymes were controlled by the succession of the fungal communities and competition scenarios rather than fungal OTU richness. Our results provide further insights into links between fungal community structure and microbialmediated ecosystem functions and processes.

Deadwood Density and Moisture Variation in a Natural Temperate Spruce-Fir-Beech Forest

“…During wood decomposition, the physical and chemical properties of wood change -wood density decreases, the C/N ratio decreases as a result of N accumulation, while lignin content increases [1,2]. Decay rate can be used to forecast how much of a given amount of decaying wood survives in any subsequent period, which can help us to predict dynamics of some ecosystem components and changes in related biodiversity [3].…”

USING Next-Generation Sequencing (NGS) TO UNCOVER DIVERSITY OF WOOD-DECAYING FUNGI IN NEOTROPICAL ATLANTIC FORESTS

“…Nine studies have already specifically investigated the mycobiomes of decaying wood using targeted, ampliconbased metagenomics, five in palearctic boreal forests in northern Europe (Ovaskainen et al 2010, Kubartova et al 2012, Ovaskainen et al 2013, Runnel et al 2015 and four in palearctic temperate forests in Europe and Asia (Van der Wal et al 2015, Hoppe et al 2015, Jang et al 2015, Yamashita et al 2015. With the exception of Yamashita et al (2015), which used the V9 region of 18S rDNA, all the other works used the complete ITS (Ovaskainen et al 2010, Kubartova et al 2012, Ovaskainen et al 2013, Hoppe et al 2015, Otosson et al 2015 or the ITS2 (Jang et al 2015, Runnel et al 2015, Van der Wal et al 2015 as the targeted region.…”

“…To date, studies specifically investigating the mycobiomes of decaying wood using targeted, amplicon-based metagenomics are few, and all of these studies were conducted strictly in palearctic boreal and temperate forests (Ovaskainen et al 2010, Kubartova et al 2012, Ovaskainen et al 2013, Van der Wal et al 2015, Hoppe et al 2015, Jang et al 2015, Runnel et al 2015, Yamashita et al 2015. Thus, as far as we know, there has not been a similar metabarcoding study in tropical, and more specifically, neotropical forests.…”

Chemical and microbiological changes in Norway spruce deadwood during the early stage of decomposition as a function of exposure in an alpine setting

“…Several factors were found to act as drivers for the changes in wood-inhabiting microbiota, such as the soil type (Sun et al 2013); wood physicochemical properties, particularly density; pH; moisture content; and total lignin and cellulose (Hoppe et al 2016;Purahong et al 2014). The wood decay stage, with an increase in fungal and bacterial abundance as wood decomposes , together with the host tree species (Hoppe et al 2016) are also of importance.…”

“…The wood decay stage, with an increase in fungal and bacterial abundance as wood decomposes , together with the host tree species (Hoppe et al 2016) are also of importance. In addition, topographic features, particularly the slope exposure, may influence the deadwood decay dynamics in subalpine environments Petrillo et al 2015).…”