Soil Microbial Biogeography in a Changing World: Recent Advances and Future Perspectives

ABSTRACT Soil microbial communities are fundamental to maintaining key soil processes associated with litter decomposition, nutrient cycling, and plant productivity and are thus integral to human well-being. Recent technological advances have exponentially increased our knowledge concerning the global ecological distributions of microbial communities across space and time and have provided evidence for their contribution to ecosystem functions. However, major knowledge gaps in soil biogeography remain to be addressed over the coming years as technology and research questions continue to evolve. In this minireview, we state recent advances and future directions in the study of soil microbial biogeography and discuss the need for a clearer concept of microbial species, projections of soil microbial distributions toward future global change scenarios, and the importance of embracing culture and isolation approaches to determine microbial functional profiles. This knowledge will be critical to better predict ecosystem functions in a changing world.

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Diversity and asynchrony in soil microbial communities stabilizes ecosystem functioning

10.1101/2020.10.02.324012 ◽

2020 ◽

Author(s):

Cameron Wagg ◽

Yann Hautier ◽

Sarah Pellkofer ◽

Samiran Banerjee ◽

Bernhard Schmid ◽

...

Keyword(s):

Microbial Diversity ◽

Microbial Communities ◽

Ecosystem Functioning ◽

Temporal Dynamics ◽

Temporal Stability ◽

Soil Microbial Communities ◽

Ecosystem Functions ◽

Soil Microbial Diversity ◽

Soil Biodiversity ◽

Soil Microbial

AbstractTheoretical and empirical advances have revealed the importance of biodiversity for stabilizing ecosystem functions through time. Yet despite the global degradation of soils, how the loss of soil microbial diversity can de-stabilizes ecosystem functioning is unknown. Here we experimentally quantified the contribution diversity and the temporal dynamics in the composition of soil microbial communities to the temporal stability of four key ecosystem functions related to nutrient and carbon cycling. Soil microbial diversity loss reduced the temporal stability of all ecosystem functions and was particularly strong when over 50% of microbial taxa were lost. The stabilizing effect of soil biodiversity was linked to asynchrony among microbial taxa whereby different soil fungi and bacteria were associated with different ecosystem functions at different times. Our results emphasize the need to conserve soil biodiversity in order to ensure the reliable provisioning of multiple ecosystems functions that soils provide to society.

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Soil Bacterial and Fungal Response to Wildfires in the Canadian Boreal Forest Across a Burn Severity Gradient

10.1101/512798 ◽

2019 ◽

Cited By ~ 2

Author(s):

Thea Whitman ◽

Ellen Whitman ◽

Jamie Woolet ◽

Mike D Flannigan ◽

Dan K Thompson ◽

...

Keyword(s):

Boreal Forest ◽

Microbial Communities ◽

Community Composition ◽

Soil Microbial Communities ◽

Total Carbon ◽

Burn Severity ◽

Ecosystem Functions ◽

Moisture Regime ◽

Soil Microbial ◽

Canadian Boreal Forest

Global fire regimes are changing, with increases in wildfire frequency and severity expected for many North American forests over the next 100 years. Fires can result in dramatic changes to C stocks and can restructure plant and microbial communities, which can have long-lasting effects on ecosystem functions. We investigated wildfire effects on soil microbial communities (bacteria and fungi) in an extreme fire season in the northwestern Canadian boreal forest, using field surveys, remote sensing, and high-throughput amplicon sequencing. We found that fire occurrence, along with vegetation community, moisture regime, pH, total carbon, and soil texture are all significant predictors of soil microbial community composition. Communities become increasingly dissimilar with increasingly severe burns, and the burn severity index (an index of the fractional area of consumed organic soils and exposed mineral soils) best predicted total bacterial community composition, while burned/unburned was the best predictor for fungi. Globally abundant taxa were identified as significant positive fire responders, including the bacteria Massilia sp. (64x more abundant with fire) and Arthrobacter sp. (35x), and the fungi Penicillium sp. (22x) and Fusicladium sp. (12x) Bacterial and fungal co-occurrence network modules were characterized by fire responsiveness as well as pH and moisture regime. Building on the efforts of previous studies, our results identify specific fire-responsive microbial taxa and suggest that accounting for burn severity improves our understanding of their response to fires, with potentially important implications for ecosystem functions.

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Deintensification of land use leads to recovery of soil microbial community composition and function after land use change in Ethiopia

10.22541/au.161770662.29935833/v1 ◽

2021 ◽

Author(s):

Yoseph Delelegn ◽

Witoon Purahong ◽

Ali Nawaz ◽

Hans Sandén ◽

Douglas Godbold ◽

...

Keyword(s):

Land Use ◽

Microbial Community ◽

Land Use Change ◽

Microbial Communities ◽

Soil Microbial Community ◽

Microbial Community Composition ◽

Soil Microbial Communities ◽

Natural Forest ◽

Ecosystem Functions ◽

Soil Microbial

Ethiopia has undergone significant land use change during the past centuries, particularly deforestation. These changes have resulted in the loss of topsoil as well as the associated soil ecosystem functions. Grazing exclusion and planting of eucalyptus are measures used to recover degraded lands and reduce deforestation, respectively. Using a gradient of the intensity of land use from natural forest to croplands, we investigated whether these measures also result in restoration of the soil microbial community. We identified the soil bacterial and fungal communities using paired-end amplicon sequencing. A total of 12,765 fungal and 12,325 bacterial OTUs were detected in the five land use types, and only ca. 2% and 17% were shared among the land uses, respectively. Total fungal and bacterial OTU richness was not significantly affected by land use change, but the conversion of forest to cropland resulted in the loss of approximately 40% and 11% of the total native fungal and bacterial OTUs, respectively. Soil pH, C, N, and aggregate stability were key factors corresponding to the overall bacterial and fungal community compositions. We also showed relationships between the microbial functional group and enzyme activities. The exclusion of grazing led to an enrichment of soil microbial communities that overlapped with the communities of the natural forest. Our results suggest that remnant native forests act as refugia for microbial communities and that restoration of microbial communities and concomitant recovery of ecosystem function via deintensification of land use is possible. Keywords: ectomycorrhiza, ericoid mycorrhiza, exclosure, microbial diversity, soil enzymes

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