Arbuscular mycorrhizal fungi in European grasslands under nutrient pollution

Feng

et al. 2020

Global Change Biology

113

Arbuscular mycorrhizal (AM) fungi are widespread and ancient root-associated microorganisms (Davison et al., 2015; Lu & Hedin, 2019). They can form mycorrhizal symbiosis with plants and thus affect many important ecosystem processes (van der Heijden et al., 2015). The well-established function for AM fungi is to improve their host uptake of soil phosphorus (P) in exchange for plant carbon (C; Marschner & Dell, 1994). In addition, they can increase crop yield (Zhang et al., 2019), regulate plant diversity

Section: N Addition Effects On Am Fungal Richness and Diversitysupporting

confidence: 90%

Responses of arbuscular mycorrhizal fungi to nitrogen addition: A meta‐analysis

Feng

et al. 2020

Global Change Biology

113

“…In this context, our results do not point towards a critical load of nitrogen deposition below which there are no harmful environmental consequences, contrary to current environmental policy (Payne et al ., 2017). In line with a recent study on arbuscular mycorrhizal fungi in European grasslands, areas of zero‐pollution or as low as possible are the only effective environmental conservation strategy for ericoid mycorrhizal fungi (Ceulemans et al ., 2019). This is particularly the case in bogs, where atmospheric nitrogen deposition showed a clear negative relationship with mycorrhizal fungal richness.…”

Section: Discussionmentioning

confidence: 99%

“…van der Linde et al ., 2018; Lilleskov et al ., 2019) and arbuscular mycorrhizal fungi from grassland and agricultural ecosystems are negatively affected by nutrient enrichment (e.g. Leff et al ., 2015; Jiang et al ., 2018; Ceulemans et al ., 2019). Although it can be expected that ericoid mycorrhizal fungi will respond similarly to nutrient pollution, empirical evidence is still lacking, particularly on a large geographical scale.…”

Section: Introductionmentioning

confidence: 99%

Diversity and community structure of ericoid mycorrhizal fungi in European bogs and heathlands across a gradient of nitrogen deposition

et al. 2020

Self Cite

Summary Despite the ecological significance of ericoid mycorrhizal fungi, little is known about the abiotic and biotic factors driving their diversity and community composition. To determine the relative importance of abiotic and biotic filtering in structuring ericoid mycorrhizal fungal communities, we established 156 sampling plots in two highly contrasting environments but dominated by the same Ericaceae plant species: waterlogged bogs and dry heathlands. Plots were located across 25 bogs and 27 dry heathlands in seven European countries covering a gradient in nitrogen deposition and phosphorus availability. Putatively ericoid mycorrhizal fungal communities in the roots of 10 different Ericaceae species were characterized using high‐throughput amplicon sequencing. Variation in ericoid mycorrhizal fungal communities was attributed to both habitat and soil variables on the one hand and host plant identity on the other. Communities differed significantly between bogs and heathlands and, in a given habitat, communities differed significantly among host plant species. Fungal richness was negatively related to nitrogen deposition in bogs and phosphorus availability in bogs and heathlands. Our results demonstrate that both abiotic and biotic filtering shapes ericoid mycorrhizal fungal communities and advocate an environmental policy minimizing excess nutrient input in these nutrient‐poor ecosystems to avoid loss of ericoid mycorrhizal fungal taxa.

“…Our results emphasized that both abundant bacterial and fungal sub-communities had higher niche breadths, which re ected their adaptations to broader ranges of environmental gradients. Environmental threshold analysis based on TITAN has been reported in some biodiversity-related studies [17,30,55]. For instance, ectomycorrhizal fungal diversity in North American…”

Section: Discussionmentioning

confidence: 99%

“…Rare and abundant microbial taxa show diverse responses to environmental change [22,25]. Environmental thresholds of arbuscular mycorrhizal fungi in European grassland are estimated using the accumulated values of change points of all the species in a given microbial community [30]. Procurable environmental thresholds rarely integrate the abundance, occurrence, and directionality of microbial responses at the species level, and little research is based on standardized phylogenetic and molecular evolutionary analysis of natural sites on a large spatial scale [17,31].…”

Section: Introductionmentioning

confidence: 99%

Stronger Environmental Adaption of Abundant than Rare Microbes in Wetland Soils from the Qinghai-Tibet Plateau

Wan

Gadd

Yang

et al. 2020

Preprint

Background: Disentangling the biogeographic patterns of rare and abundant microbial sub-communities is essential in order to understand the generation and maintenance of microbial diversity with respect to the functions they provide. However, little is known about ecological assembly processes and environmental adaptation of rare and abundant microbial sub-communities across large spatial-scale wetlands. Using Illumina sequencing, we investigated the taxonomic and phylogenetic β-diversity of rare and abundant bacterial and fungal sub-communities in Qinghai-Tibet Plateau wetland soils. Additionally, we determined environmental breadths and phylogenetic signals of ecological preferences of rare and abundant microbial sub-communities, and investigated community assembly processes of microbial taxa. Results: We found that both taxonomic and phylogenetic similarities of rare and abundant microbial sub-communities attenuated with geographical distance. Based on threshold indicator taxa analysis and Blomberg’s K statistic, abundant microbial taxa exhibited broader environmental thresholds and stronger phylogenetic signals for ecological traits than rare microbial taxa. The strong correlations between community compositional dissimilarity and phylogenetic distance of rare microbial sub-communities also revealed that rare taxa may be more sensitive to environmental changes. In addition, the rare microbial sub-communities exhibited closer phylogenetic clustering compared with abundant microbial sub-communities. The null model analysis revealed that dispersal limitation belonging to stochastic process dominated ecological assembly of abundant bacterial sub-community, and rare and abundant fungal sub-communities; variable selection belonging to deterministic process governed community assembly of rare bacterial taxa. Neutral model analysis and variation partitioning analysis further confirmed that abundant microbial sub-communities were less environmentally constrained. Soil ammonia nitrogen was the crucial factor in mediating the balance between stochasticity and determinism of both rare and abundant microbial sub-communities, as reflected by distinct differences in stochastic process with higher ammonia nitrogen content.Conclusions: Abundant microbial sub-communities may have better environmental adaptation potential and are less dispersed by environmental changes compared with rare microbial sub-communities. Our findings extend knowledge of the adaptation of rare and abundant microbial taxa to ongoing environmental change and could facilitate prediction of biodiversity loss caused by global climate change and increasing human activity in wetlands of the Qinghai-Tibet Plateau.