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The home-field advantage (HFA) hypothesis has been used intensively to study leaf litter decomposition in various ecosystems. However, the HFA in woody substrates is still unexplored. Here, we reanalyzed and integrated existing datasets on various groups of microorganisms collected from natural deadwood of two temperate trees, Fagus sylvatica and Picea abies, from forests in which one or other of these species dominates but where both are present. Our aims were (i) to test the HFA hypothesis on wood decomposition rates of these two temperate tree species, and (ii) to investigate if HFA hypothesis can be explained by diversity and community composition of bacteria and in detail N-fixing bacteria (as determined by molecular 16S rRNA and nifH gene amplification) and fungi (as determined by molecular ITS rRNA amplification and sporocarp surveys). Our results showed that wood decomposition rates were accelerated at "home" versus "away" by 38.19% ± 20.04% (mean ± SE). We detected strong changes in fungal richness (increase 36–50%) and community composition (RANOSIM = 0.52–0.60, P < 0.05) according to HFA hypothesis. The changes of fungi were much stronger than for total bacteria and nitrogen fixing for both at richness and community composition levels. In conclusion, our results support the HFA hypothesis in deadwood: decomposition rate is accelerated at home due to specialization of fungal communities produced by the plant community above them. Furthermore, the higher richness of fungal sporocarps and nitrogen-fixing bacteria (nifH) may stimulate or at least stabilize wood decomposition rates at "home" versus "away." [ABSTRACT FROM AUTHOR]

Next‐generation sequencing (NGS) has significantly increased knowledge of microbial communities and their distribution. However, it is still not common to apply NGS technology to microbial conservation. We sought to use NGS technologies to evaluate conservation strategies for wood‐inhabiting fungi. Evaluating a deadwood experiment 3 years after it was established, we specifically examined which tree species combinations promoted the highest richness of wood‐inhabiting fungi. Deadwood enrichment was an effective strategy and logs of 6 tree species, either those with the highest wood‐inhabiting fungal α and γ diversity or those with the highest β diversity, maintained >1,000 operational taxonomic units (OTUs) spread over a wide range of taxonomic groups. In comparison, a conservation strategy based only on the results of sporocarp surveys yielded 591 OTUs. This result highlights the need to use NGS approaches to inform microbial conservation strategies. We also determined that 5 tree species with the highest saproxylic beetle γ diversity simultaneously conserved wood‐inhabiting fungi. Apart from deadwood volume, we suggest data on deadwood quality and species also be included as indicators, especially for wood‐inhabiting fungal diversity, and incorporated quickly in forest assessment and monitoring systems in Central Europe. Article impact statement: Enrichment of the species diversity of deadwood is an effective strategy for wood‐inhabiting fungal conservation in temperate forests. [ABSTRACT FROM AUTHOR]

Summary: Nitrogen deposition can strongly affect biodiversity, but its specific effects on terrestrial microbial communities and their roles for ecosystem functions and processes are still unclear. Here, we investigated the impacts of N deposition on wood‐inhabiting fungi (WIF) and their related ecological functions and processes in a highly N‐limited deadwood habitat. Based on high‐throughput sequencing, enzymatic activity assay and measurements of wood decomposition rates, we show that N addition has no significant effect on the overall WIF community composition or on related ecosystem functions and processes in this habitat. Nevertheless, we detected several switches in presence/absence (gain/loss) of wood‐inhabiting fungal OTUs due to the effect of N addition. The responses of WIF differed from previous studies carried out with fungi living in soil and leaf‐litter, which represent less N‐limited fungal habitats. Our results suggest that adaptation at different levels of organization and functional redundancy may explain this buffered response and the resistant microbial‐mediated ecosystem function and processes against N deposition in highly N‐limited habitats. [ABSTRACT FROM AUTHOR]

Stingless bees play a crucial role in the environment and agriculture as they are effective pollinators. Furthermore, they can produce various products that can be exploited economically, such as propolis and honey. Despite their economic value, the knowledge of microbial community of stingless bees, and their roles on the bees' health, especially in Thailand, are in its infancy. This study aimed to investigate the composition and the functions of bacterial community associated with Tetragonula pagdeni stingless bees using culture-independent and culture-dependent approaches with emphasis on lactic acid bacteria. The culture-independent results showed that the dominant bacterial phyla were Firmicutes, Proteobacteria and Actinobacteria. The most abundant families were Lactobacillaceae and Halomonadaceae. Functional prediction indicated that the prevalent functions of bacterial communities were chemoheterotrophy and fermentation. In addition, the bacterial community might be able to biosynthesize amino acid and antimicrobial compounds. Further isolation and characterization resulted in isolates that belonged to the dominant taxa of the community and possessed potentially beneficial metabolic activity. This suggested that they are parts of the nutrient acquisition and host defense bacterial functional groups in Thai commercial stingless bees. [ABSTRACT FROM AUTHOR]

The incomplete degradation of bio-based and biodegradable plastics (BBPs) in soils causes multiple threats to soil quality, human health, and food security. Plastic residuals can interact with soil microbial communities. We aimed to link the structure and enzyme-mediated functional traits of a microbial community composition that were present during poly (butylene succinate-co-butylene adipate (PBSA) decomposition in soil with (PSN) and without (PS) the addition of nitrogen fertilizer ((NH4)2SO4). We identified bacterial (Achromobacter, Luteimonas, Rhodanobacter, and Lysobacter) and fungal (Fusarium, Chaetomium, Clonostachys, Fusicolla, and Acremonium) taxa that were linked to the activities of ß-glucosidase, chitinase, phosphatase, and lipase in plastic-amended soils. Fungal biomass increased by 1.7 and 4 times in PS and PSN treatment, respectively, as compared to non-plastic amended soil. PBSA significantly changed the relationships between soil properties (C: N ratio, TN, and pH) and microbial community structure; however, the relationships between fungal biomass and soil enzyme activities remained constant. PBSA significantly altered the relationship between fungal biomass and acid phosphatase. We demonstrated that although the soil functions related to nutrient cycling were not negatively affected in PSN treatment, potential negative effects are reasoned by the enrichment of plant pathogens. We concluded that in comparison to fungi, the bacteria demonstrated a broader functional spectrum in the BBP degradation process. [ABSTRACT FROM AUTHOR]

• The microbial co-occurrence networks along soil depths in Mt. Oakley were analyzed. • There were contrasting patterns between soil bacterial and fungal diversity along altitudinal gradient. • Altitude was more important than soil depth for shaping soil microbial communities. • Main drivers of microbial community structure are consistent for whole and sub-network communities. • Sub-network community analysis revealed important drivers that do not capture by whole community. Soil bacterial and fungal communities with different key ecological functions play important roles in boreal forest ecosystems. Although several studies have reported on the altitudinal distribution patterns of microbes, our understanding of the characteristics of the microbial community and the core composition of the microbiome in cold-temperate montane forests is still limited. In this study, Illumina MiSeq sequencing was used to investigate the changes in soil bacterial and fungal communities in surface and subsurface soils along an altitudinal gradient (from 830 m to 1300 m) on Oakley Mountain. The diversity of the bacterial and fungal communities showed a monotonic decrease and a monotonic increase with altitude, respectively. The influence of altitude on the bacterial and fungal community composition was stronger than that of soil depth. The variations in pH and dissolved organic nitrogen content at different altitudes were the main factors influencing the bacterial and fungal community structures, respectively. There was no obvious difference between the network structures of the surface and subsurface soil fungal communities, while the network of the subsurface soil bacterial community was more complex and intricate than that of the surface soil bacterial community. The network nodes mainly belonging to Proteobacteria and Actinobacteria were the key bacterial taxa in the two soil layers. Although the main drivers of microbial community structure are consistent for whole and sub-nerwork communities, the subnetwork community analysis revealed other important drivers (i.e. soil temperature and nitrate nitrogen) that do not capture by whole community analysis. Thus, the more comprehensive picture of the important factors shaping microbial community structure can be achieved by combining whole and subnetwork community analyses. Our results demonstrated that altitude had a stronger influence on soil bacterial and fungal communities than soil depth and that bacterial and fungal communities showed divergent patterns with altitude and soil depth. [ABSTRACT FROM AUTHOR]