Long-term effects of organic amendments on the recovery of plant and soil microbial communities following disturbance in the 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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Long-Term Effects of Soil Remediation with Willow Short Rotation Coppice on Biogeographic Pattern of Microbial Functional Genes

Microorganisms ◽

10.3390/microorganisms10010140 ◽

2022 ◽

Vol 10 (1) ◽

pp. 140

Author(s):

Wenjing Liu ◽

Kai Xue ◽

Runpeng Hu ◽

Jizhong Zhou ◽

Joy D. Van Nostrand ◽

...

Keyword(s):

Microbial Communities ◽

Gene Diversity ◽

Soil Microbial Communities ◽

Short Rotation Coppice ◽

Functional Genes ◽

Long Term Effects ◽

Soil Microbial ◽

Biogeographic Pattern ◽

Short Rotation

Short rotation coppice (SRC) is increasingly being adopted for bioenergy production, pollution remediation and land restoration. However, its long-term effects on soil microbial communities are poorly characterized. Here, we studied soil microbial functional genes and their biogeographic pattern under SRC with willow trees as compared to those under permanent grassland (C). GeoChip analysis showed a lower functional gene diversity in SRC than in C soil, whereas microbial ATP and respiration did not change. The SRC soil had lower relative abundances of microbial genes encoding for metal(-oid) resistance, antibiotic resistance and stress-related proteins. This indicates a more benign habitat under SRC for microbial communities after relieving heavy metal stress, consistent with the lower phytoavailability of some metals (i.e., As, Cd, Ni and Zn) and higher total organic carbon, NO3−-N and P concentrations. The microbial taxa–area relationship was valid in both soils, but the space turnover rate was higher under SRC within 0.125 m2, which was possibly linked to a more benign environment under SRC, whereas similar values were reached beyond thisarea. Overall, we concluded that SRC management can be considered as a phytotechnology that ameliorates the habitat for soil microorganisms, owing to TOC and nutrient enrichment on the long-term.

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Long-term effects of biochar amendment on rhizosphere and bulk soil microbial communities in a karst region, southwest China

Applied Soil Ecology ◽

10.1016/j.apsoil.2019.04.017 ◽

2019 ◽

Vol 140 ◽

pp. 126-134 ◽

Cited By ~ 4

Author(s):

Jianzhong Cheng ◽

Xinqing Lee ◽

Yuan Tang ◽

Qinghai Zhang

Keyword(s):

Microbial Communities ◽

Southwest China ◽

Soil Microbial Communities ◽

Bulk Soil ◽

Karst Region ◽

Long Term Effects ◽

Soil Microbial ◽

Biochar Amendment

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Long-Term Effects of Perfluorooctanoic Acid (PFOA) and Perfluorooctane Sulfonic Acid (PFOS) on Soil Microbial Community

10.21203/rs.3.rs-190229/v1 ◽

2021 ◽

Author(s):

Wan Tao ◽

Rui Xu ◽

Hanzhi Lin ◽

Duanyi Huang ◽

Pingzhou Su ◽

...

Keyword(s):

Microbial Community ◽

Microbial Communities ◽

High Throughput Sequencing ◽

Gene Prediction ◽

Soil Microbial Communities ◽

Alpha Diversity ◽

Perfluorooctanoic Acid ◽

Long Term Effects ◽

Soil Microbial

Abstract The extensive application of perfluoroalkyl and polyfluoroalkyl substances (PFASs) causes their frequent detection in various environments. Nevertheless, the effects of PFASs exposure on environmental microorganisms still remain unknown. In current work, two typical PFASs, perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS), are selected to investigate their long-term effects on soil microbes. Microbial community structure and diversity were investigated by high-throughput sequencing and multiple statistical methods. Under 90-days of exposure, PFAS treatments increased the alpha-diversity of soil microbial communities with PFOS treatment, followed by PFOA treatment. The long-term exposure of PFASs substantially changed the compositions of soil microbial communities. The most abundant phylum Proteobacteria decreased from 82.9% (without amended PFASs) to 62.1% (with PFOA treatment) and 77.8% (with PFOS treatment). As a comparison, the relative abundance of Bacteroidetes, Chloroflexi, Acidobacteria, and Ignavibacteriae increased in the PFOA or PFOS groups. Comparative co-occurrence networks were constructed to investigate the biotic interactions in the two treatments. It was found that most taxonomy nodes in the PFOA and PFOS networks were associated with the genus Hydrogenophaga and Pseudoxanthomonas, respectively. The LEfSe analysis identified a set of core taxonomies (e.g., Azospirillum, Methyloversatilis, Ancylobacter, Hydrogenophaga, and Methylomonas) in the soil microbial communities and suggested their different preferences to PFAS exposures. Functional gene prediction suggested that the microbial metabolism processes, such as nucleotide transport and metabolism, cell motility, carbohydrate transport and metabolism, energy production and conversion, and secondary metabolites biosynthesis transport and catabolism, might be significantly inhibited under PFAS exposure, which may further affect soil ecological services.

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