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

2019 ◽  
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.

scholarly journals Towards a function-first framework to make soil microbial ecology predictive

2021 ◽  
Author(s):  
Johannes Rousk ◽  
Lettice Hicks
Keyword(s):  
Microbial Community ◽  
Environmental Factors ◽  
Microbial Communities ◽  
Functional Response ◽  
Community Composition ◽  
Ecosystem Function ◽  
Bacterial Growth ◽  
Response Curve ◽  
Ecosystem Functions ◽  
Soil Microbial

<p>Soil microbial communities perform vital ecosystem functions, such as the decomposition of organic matter to provide plant nutrition. However, despite the functional importance of soil microorganisms, attribution of ecosystem function to particular constituents of the microbial community has been impeded by a lack of information linking microbial function to community composition and structure. Here, we propose a function-first framework to predict how microbial communities influence ecosystem functions.</p><p>We first view the microbial community associated with a specific function as a whole, and describe the dependence of microbial functions on environmental factors (e.g. the intrinsic temperature dependence of bacterial growth rates). This step defines the aggregate functional response curve of the community. Second, the contribution of the whole community to ecosystem function can be predicted, by combining the functional response curve with current environmental conditions. Functional response curves can then be linked with taxonomic data in order to identify sets of “biomarker” taxa that signal how microbial communities regulate ecosystem functions. Ultimately, such indicator taxa may be used as a diagnostic tool, enabling predictions of ecosystem function from community composition.</p><p>In this presentation, we provide three examples to illustrate the proposed framework, whereby the dependence of bacterial growth on environmental factors, including temperature, pH and salinity, is defined as the functional response curve used to interlink soil bacterial community structure and function. Applying this framework will make it possible to predict ecosystem functions directly from microbial community composition.</p>

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

mSystems ◽  
2020 ◽  
Vol 5 (2) ◽  
Author(s):  
Haiyan Chu ◽  
Gui-Feng Gao ◽  
Yuying Ma ◽  
Kunkun Fan ◽  
Manuel Delgado-Baquerizo
Keyword(s):  
Microbial Communities ◽  
Soil Microbial Communities ◽  
Well Being ◽  
Ecosystem Functions ◽  
Soil Microbial ◽  
Microbial Biogeography ◽  
Recent Advances ◽  
Technological Advances ◽  
Global Change Scenarios ◽  
Changing World

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.

scholarly journals Response of Soil Microbial Communities to Warming and Clipping in Alpine Meadows in Northern Tibet

2020 ◽  
Vol 12 (14) ◽  
pp. 5617
Author(s):  
Haorui Zhang ◽  
Shaowei Li ◽  
Guangyu Zhang ◽  
Gang Fu
Keyword(s):  
Microbial Communities ◽  
Community Composition ◽  
Soil Microbial Communities ◽  
Alpine Meadows ◽  
Soil Microbial ◽  
Alpine Steppe ◽  
Total Plfa ◽  
Kobresia Meadow ◽  
Low Altitude ◽  
Steppe Meadow

In order to explore responses of soil microbial communities among different alpine meadows under warming and clipping, soil microorganisms of three alpine meadow sites (low altitude: 4313 m, alpine steppe meadow, 30°30′ N, 91°04′ E; mid-altitude: 4513 m, alpine steppe meadow, 30°31′ N, 91°04′ E; and high altitude: 4693, alpine Kobresia meadow, 30°32′ N, 91°03′ E) were measured using the phospholipid fatty acid (PLFA) method. Both warming and clipping significantly reduced PLFA content and changed the community composition of soil microbial taxa, which belong to bacterial and fungal communities in the alpine Kobresia meadow. Warming significantly reduced the soil total PLFA content by 36.1% and the content of soil fungi by 37.0%; the clipping significantly reduced the soil total PLFA content by 57.4%, the content of soil fungi by 49.9%, and the content of soil bacteria by 60.5% in the alpine Kobresia meadow. Only clipping changed the total fungal community composition at a low altitude. Neither clipping nor warming changed the microbial community composition at a moderate altitude. Soil temperature, soil moisture, and pH were the main factors affecting soil microbial communities. Therefore, the effects of warming and clipping on soil microbial communities in alpine meadows were related to grassland types and soil environmental conditions.

scholarly journals Effects of Wildfire and Harvest Disturbances on Forest Soil Bacterial Communities

2007 ◽  
Vol 74 (1) ◽  
pp. 216-224 ◽  
Author(s):  
Nancy R. Smith ◽  
Barbara E. Kishchuk ◽  
William W. Mohn
Keyword(s):  
Microbial Biomass ◽  
Microbial Communities ◽  
Community Composition ◽  
Denaturing Gradient Gel Electrophoresis ◽  
Microbial Biomass Carbon ◽  
Bacterial Community Composition ◽  
Soil Microbial Communities ◽  
Rrna Gene ◽  
Microbial Biomass Nitrogen ◽  
Soil Microbial

ABSTRACT Wildfires and harvesting are important disturbances to forest ecosystems, but their effects on soil microbial communities are not well characterized and have not previously been compared directly. This study was conducted at sites with similar soil, climatic, and other properties in a spruce-dominated boreal forest near Chisholm, Alberta, Canada. Soil microbial communities were assessed following four treatments: control, harvest, burn, and burn plus timber salvage (burn-salvage). Burn treatments were at sites affected by a large wildfire in May 2001, and the communities were sampled 1 year after the fire. Microbial biomass carbon decreased 18%, 74%, and 53% in the harvest, burn, and burn-salvage treatments, respectively. Microbial biomass nitrogen decreased 25% in the harvest treatment, but increased in the burn treatments, probably because of microbial assimilation of the increased amounts of available NH4 + and NO3 − due to burning. Bacterial community composition was analyzed by nonparametric ordination of molecular fingerprint data of 119 samples from both ribosomal intergenic spacer analysis (RISA) and rRNA gene denaturing gradient gel electrophoresis. On the basis of multiresponse permutation procedures, community composition was significantly different among all treatments, with the greatest differences between the two burned treatments versus the two unburned treatments. The sequencing of DNA bands from RISA fingerprints revealed distinct distributions of bacterial divisions among the treatments. Gamma- and Alphaproteobacteria were highly characteristic of the unburned treatments, while Betaproteobacteria and members of Bacillus were highly characteristic of the burned treatments. Wildfire had distinct and more pronounced effects on the soil microbial community than did harvesting.

scholarly journals Diversity and asynchrony in soil microbial communities stabilizes ecosystem functioning

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.

scholarly journals Impact of Soil Disinfestation on Fungal and Bacterial Communities in Soil With Cucumber Cultivation

2021 ◽  
Vol 12 ◽  
Author(s):  
Yan Wang ◽  
Yujie Jin ◽  
Ping Han ◽  
Jianjun Hao ◽  
Hongyu Pan ◽  
...  
Keyword(s):  
Microbial Diversity ◽  
Microbial Communities ◽  
Soil Microbial Communities ◽  
Enzymatic Activities ◽  
Soil Treatment ◽  
Total Carbon ◽  
Soil Microbiome ◽  
Soil Microbial Diversity ◽  
Soil Microbial ◽  
The Difference

Soil treatment with disinfectants has been used for controlling soilborne phytopathogens. Besides suppressing specific pathogens, how these disinfectants impact soil health, especially soil microbial communities, is yet to be systemically determined. The objectives of this study were to examine the effects of three representative disinfectants, including the dazomet fumigant, fenaminosulf fungicide, and kasugamycin antibiotic on chemical properties, enzymatic activities, and microbial communities in soil for cucumber cultivation. Results showed that 14 days after soil treatment with these chemicals, residual content of dazomet and kasugamycin quickly declined in soil and were undetectable, while fenaminosulf residues were found at 0.48 ± 0.01 mg/kg. Total nitrogen and total carbon increased in soil after dazomet treatment. Urease and sucrase activities were significantly restrained after disinfectant application. The disinfectants did not significantly change the taxon of predominant bacteria and fungi but altered the relative abundance and diversity of soil microbiome, as well as microbial interspecific relationships. Moreover, cucumber cultivation enhanced the overall soil microbial diversity and enzymatic activities, which diminished the difference of soil microbiome among four treatments. The difference in soil microbial diversity among the four treatments became smaller after planting cucumber. Thus, soil microbial communities were affected by soil disinfectants and gradually recovered by cucumber application.

scholarly journals Apple Root stocks and Pre-plant Soil Treatments Alter Soil Microbial Community Composition in a New York Orchard

HortScience ◽  
2005 ◽  
Vol 40 (4) ◽  
pp. 1128C-1128
Author(s):  
Shengrui Yao ◽  
Ian A. Merwin ◽  
Janice E. Thies
Keyword(s):  
Microbial Community ◽  
Microbial Communities ◽  
Community Composition ◽  
Soil Microbial Community ◽  
Microbial Community Composition ◽  
Soil Microbial Communities ◽  
Growth And Yield ◽  
Soil Microbial ◽  
Plant Soil ◽  
Soil Microbial Community Composition

Apple (Malu ×domestica) replant disease (ARD) is a soil-borne disease syndrome of complex etiology that occurs worldwide when establishing new orchards in old fruit-growing sites. Methyl bromide (MB) has been an effective soil fumigant to control ARD, but safer alternatives to MB are needed. We evaluated soil microbial communities, tree growth, and fruit yield for three pre-plant soil treatments (compost amendment, soil treatment with a broad-spectrum fumigant, and untreated controls), and five clonal rootstocks (M7, M26, CG6210, CG30, and G16), in an apple replant site at Ithaca, N.Y. Molecular fingerprinting (PCR-DGGE) techniques were used to study soil microbial community composition of root-zone soil of the different soil treatments and rootstocks. Tree caliper, shoot growth, and yield were measured annually from 2002–04. Among the five rootstocks we compared, trees on CG6210 had the most growth and yield, while trees on M26 had the least growth and yield. Soil treatments altered soil microbial communities during the year after pre-plant treatments, and each treatment was associated with distinct microbial groups in hierarchical cluster analyses. However, those differences among fungal and bacterial communities diminished during the second year after planting, and soil fungal communities equilibrated faster than bacterial communities. Pre-plant soil treatments altered bulk-soil microbial community composition, but those shifts in soil microbial communities had no obvious correlation with tree performance. Rootstock genotypes were the dominant factor in tree performance after 3 years of observations, and different rootstocks were associated with characteristic bacterial, pseudomonad, fungal, and oomycetes communities in root-zone soil.

scholarly journals Patterns of local, intercontinental and interseasonal variation of soil bacterial and eukaryotic microbial communities

2020 ◽  
Vol 96 (3) ◽  
Author(s):  
Johan De Gruyter ◽  
James T Weedon ◽  
Stéphane Bazot ◽  
Steven Dauwe ◽  
Pere-Roc Fernandez-Garberí ◽  
...  
Keyword(s):  
Temporal Variation ◽  
Microbial Communities ◽  
Community Composition ◽  
Temporal Dynamics ◽  
Soil Microbial Communities ◽  
Soil Microbiome ◽  
Ongoing Research ◽  
Soil Microbial ◽  
Spatio Temporal ◽  
Microbial Groups

ABSTRACT Although ongoing research has revealed some of the main drivers behind global spatial patterns of microbial communities, spatio-temporal dynamics of these communities still remain largely unexplored. Here, we investigate spatio-temporal variability of both bacterial and eukaryotic soil microbial communities at local and intercontinental scales. We compare how temporal variation in community composition scales with spatial variation in community composition, and explore the extent to which bacteria, protists, fungi and metazoa have similar patterns of temporal community dynamics. All soil microbial groups displayed a strong correlation between spatial distance and community dissimilarity, which was related to the ratio of organism to sample size. Temporal changes were variable, ranging from equal to local between-sample variation, to as large as that between communities several thousand kilometers apart. Moreover, significant correlations were found between bacterial and protist communities, as well as between protist and fungal communities, indicating that these microbial groups change in tandem, potentially driven by interactions between them. We conclude that temporal variation can be considerable in soil microbial communities, and that future studies need to consider temporal variation in order to reliably capture all drivers of soil microbiome changes.

scholarly journals Effects of different nitrogen additions on soil microbial communities in different seasons in a boreal forest

Ecosphere ◽  
2017 ◽  
Vol 8 (7) ◽  
pp. e01879 ◽  
Author(s):  
Guoyong Yan ◽  
Yajuan Xing ◽  
Lijian Xu ◽  
Jianyu Wang ◽  
Xiongde Dong ◽  
...  
Keyword(s):  
Boreal Forest ◽  
Microbial Communities ◽  
Soil Microbial Communities ◽  
Soil Microbial ◽  
Different Seasons ◽  
Nitrogen Additions
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