1
|
Zhang M, Fu L, Ma D, Wang X, Liu A. Effects of Microtopography on Soil Microbial Community Structure and Abundance in Permafrost Peatlands. Microorganisms 2024; 12:867. [PMID: 38792697 PMCID: PMC11124213 DOI: 10.3390/microorganisms12050867] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2024] [Revised: 04/22/2024] [Accepted: 04/24/2024] [Indexed: 05/26/2024] Open
Abstract
Soil microorganisms play crucial roles in the stability of the global carbon pool, particularly in permafrost peatlands that are highly sensitive to climate change. Microtopography is a unique characteristic of peatland ecosystems, but how microtopography affects the microbial community structures and their functions in the soil is only partially known. We characterized the bacterial and fungal community compositions by amplicon sequencing and their abundances via quantitative PCR at different soil depths in three microtopographical positions (hummocks, flats, and hollows) in permafrost peatland of the Greater Xing'an Mountains in China. The results showed that the soil of hummocks displayed a higher microbial diversity compared to hollows. Microtopography exerted a strong influence on bacterial community structure, while both microtopography and soil depth greatly impacted the fungal community structure with variable effects on fungal functional guilds. Soil water content, dissolved organic carbon, total phosphorus, and total nitrogen levels of the soil mostly affected the bacterial and fungal communities. Microtopography generated variations in the soil water content, which was the main driver of the spatial distribution of microbial abundances. This information stressed that the hummock-flat-hollow microtopography of permafrost peatlands creates heterogeneity in soil physicochemical properties and hydrological conditions, thereby influencing soil microbial communities at a microhabitat scale. Our results imply that changes to the water table induced by climate warming inducing permafrost degradation will impact the composition of soil microbes in peatlands and their related biogeochemical functions, eventually providing feedback loops into the global climate system.
Collapse
Affiliation(s)
- Man Zhang
- College of Geographical Sciences, Harbin Normal University, Harbin 150025, China; (M.Z.); (L.F.); (X.W.); (A.L.)
- Heilongjiang Wuyiling Wetland Ecosystem National Observation and Research Station, Yichun 153000, China
| | - Lingyu Fu
- College of Geographical Sciences, Harbin Normal University, Harbin 150025, China; (M.Z.); (L.F.); (X.W.); (A.L.)
- Heilongjiang Wuyiling Wetland Ecosystem National Observation and Research Station, Yichun 153000, China
| | - Dalong Ma
- College of Geographical Sciences, Harbin Normal University, Harbin 150025, China; (M.Z.); (L.F.); (X.W.); (A.L.)
- Heilongjiang Wuyiling Wetland Ecosystem National Observation and Research Station, Yichun 153000, China
| | - Xu Wang
- College of Geographical Sciences, Harbin Normal University, Harbin 150025, China; (M.Z.); (L.F.); (X.W.); (A.L.)
- Heilongjiang Wuyiling Wetland Ecosystem National Observation and Research Station, Yichun 153000, China
| | - Anwen Liu
- College of Geographical Sciences, Harbin Normal University, Harbin 150025, China; (M.Z.); (L.F.); (X.W.); (A.L.)
- Heilongjiang Wuyiling Wetland Ecosystem National Observation and Research Station, Yichun 153000, China
| |
Collapse
|
2
|
Buttler A, Bragazza L, Laggoun-Défarge F, Gogo S, Toussaint ML, Lamentowicz M, Chojnicki BH, Słowiński M, Słowińska S, Zielińska M, Reczuga M, Barabach J, Marcisz K, Lamentowicz Ł, Harenda K, Lapshina E, Gilbert D, Schlaepfer R, Jassey VEJ. Ericoid shrub encroachment shifts aboveground-belowground linkages in three peatlands across Europe and Western Siberia. GLOBAL CHANGE BIOLOGY 2023; 29:6772-6793. [PMID: 37578632 DOI: 10.1111/gcb.16904] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Revised: 07/19/2023] [Accepted: 07/23/2023] [Indexed: 08/15/2023]
Abstract
In northern peatlands, reduction of Sphagnum dominance in favour of vascular vegetation is likely to influence biogeochemical processes. Such vegetation changes occur as the water table lowers and temperatures rise. To test which of these factors has a significant influence on peatland vegetation, we conducted a 3-year manipulative field experiment in Linje mire (northern Poland). We manipulated the peatland water table level (wet, intermediate and dry; on average the depth of the water table was 17.4, 21.2 and 25.3 cm respectively), and we used open-top chambers (OTCs) to create warmer conditions (on average increase of 1.2°C in OTC plots compared to control plots). Peat drying through water table lowering at this local scale had a larger effect than OTC warming treatment per see on Sphagnum mosses and vascular plants. In particular, ericoid shrubs increased with a lower water table level, while Sphagnum decreased. Microclimatic measurements at the plot scale indicated that both water-level and temperature, represented by heating degree days (HDDs), can have significant effects on the vegetation. In a large-scale complementary vegetation gradient survey replicated in three peatlands positioned along a transitional oceanic-continental and temperate-boreal (subarctic) gradient (France-Poland-Western Siberia), an increase in ericoid shrubs was marked by an increase in phenols in peat pore water, resulting from higher phenol concentrations in vascular plant biomass. Our results suggest a shift in functioning from a mineral-N-driven to a fungi-mediated organic-N nutrient acquisition with shrub encroachment. Both ericoid shrub encroachment and higher mean annual temperature in the three sites triggered greater vascular plant biomass and consequently the dominance of decomposers (especially fungi), which led to a feeding community dominated by nematodes. This contributed to lower enzymatic multifunctionality. Our findings illustrate mechanisms by which plants influence ecosystem responses to climate change, through their effect on microbial trophic interactions.
Collapse
Affiliation(s)
- Alexandre Buttler
- School of Architecture, Civil and Environmental Engineering (ENAC), Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Lausanne, Switzerland
| | - Luca Bragazza
- Agroscope, Field-Crop Systems and Plant Nutrition, Nyon, Switzerland
| | | | - Sebastien Gogo
- UMR-CNRS 6553 ECOBIO, Université de Rennes, Rennes, France
| | - Marie-Laure Toussaint
- Laboratoire de Chrono-Environnement, UMR, CNRS 6249, UFR des Sciences et Techniques, Université de Franche-Comté, Besançon, France
| | - Mariusz Lamentowicz
- Climate Change Ecology Research Unit, Faculty of Geographical and Geological Sciences, Adam Mickiewicz University, Poznań, Poland
| | - Bogdan H Chojnicki
- Laboratory of Bioclimatology, Department of Ecology and Environmental Protection, Faculty of Environmental and Mechanical Engineering, Poznan University of Life Sciences, Poznań, Poland
| | - Michał Słowiński
- Past Landscape Dynamic Laboratory, Institute of Geography and Spatial Organization, Polish Academy of Sciences, Warsaw, Poland
| | - Sandra Słowińska
- Climate Research Department, Institute of Geography and Spatial Organization, Polish Academy of Sciences, Warsaw, Poland
| | - Małgorzata Zielińska
- Climate Change Ecology Research Unit, Faculty of Geographical and Geological Sciences, Adam Mickiewicz University, Poznań, Poland
| | - Monika Reczuga
- Climate Change Ecology Research Unit, Faculty of Geographical and Geological Sciences, Adam Mickiewicz University, Poznań, Poland
| | - Jan Barabach
- Department of Land Improvement, Environmental Development and Spatial Management, Poznan University of Life Sciences, Poznań, Poland
| | - Katarzyna Marcisz
- Climate Change Ecology Research Unit, Faculty of Geographical and Geological Sciences, Adam Mickiewicz University, Poznań, Poland
| | - Łukasz Lamentowicz
- Climate Change Ecology Research Unit, Faculty of Geographical and Geological Sciences, Adam Mickiewicz University, Poznań, Poland
| | - Kamila Harenda
- Laboratory of Bioclimatology, Department of Ecology and Environmental Protection, Faculty of Environmental and Mechanical Engineering, Poznan University of Life Sciences, Poznań, Poland
| | | | - Daniel Gilbert
- Laboratoire de Chrono-Environnement, UMR, CNRS 6249, UFR des Sciences et Techniques, Université de Franche-Comté, Besançon, France
| | - Rodolphe Schlaepfer
- School of Architecture, Civil and Environmental Engineering (ENAC), Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Vincent E J Jassey
- School of Architecture, Civil and Environmental Engineering (ENAC), Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Lausanne, Switzerland
- Laboratoire d'Ecologie Fonctionnelle et Environnement, CNRS, Université de Toulouse, Toulouse, France
| |
Collapse
|
3
|
Healy MG, Siggins A, Molloy K, Potito AP, O'Leary D, Daly E, Callery O. The impact of alternating drainage and inundation cycles on geochemistry and microbiology of intact peat cores. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 858:159664. [PMID: 36306832 DOI: 10.1016/j.scitotenv.2022.159664] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Revised: 10/10/2022] [Accepted: 10/19/2022] [Indexed: 06/16/2023]
Abstract
The rewetting of degraded peatlands has been adopted as a method to address climate change. Concerns have been raised about the effects of peat inundation and drying cycles, in more extreme climate events, on the potential release of nitrogen (N) species, in particular ammonium (NH4-N), once rewetted, as well as the physico-chemical and biological properties of the peat. This study used intact peat cores to measure the impact of two different cycles of peat inundation and drying (1 month and 2 month) over a total study duration of 56 weeks on the (1) NH4-N, nitrate-N (NO3-N) and dissolved reactive phosphorus (DRP) in the soil pore water; (2) microbial community structure; (3) physico-chemical properties of the peat; and (4) the structure of the peat, and therefore its ability to mitigate flood risks and storm surges. The study found that rewetted cores released NO3-N in the pore water up to a concentration of 6.25 mg L-1, but had no appreciable impact on NH4-N, which remained below 1.7 mg L-1 over the study duration. DRP moved quickly though the upper layers of the cores, but physico-chemical analysis suggested it was adsorbed to more iron-rich soil, which was present at depths below 0.4 m in the cores. Time intervals between inundation produced no significant difference on the forms of inorganic N released, nor did it compact the soil or change the microbial community structure. The depth of the water table, however, had a significant impact on inorganic N release, particularly NO3-N, which indicates that this N species, and not NH4-N, may be problematic in rewetted peatlands.
Collapse
Affiliation(s)
- M G Healy
- Civil Engineering, College of Science and Engineering, University of Galway, Ireland; Ryan Institute, University of Galway, Ireland.
| | - A Siggins
- Civil Engineering, College of Science and Engineering, University of Galway, Ireland; Ryan Institute, University of Galway, Ireland; Microbiology, School of Biological and Chemical Sciences, College of Science and Engineering, University of Galway, Ireland
| | - K Molloy
- Ryan Institute, University of Galway, Ireland; Paleoenvironmental Research Unit, School of Geography, Archaeology and Irish Studies, College of Arts, Social Sciences, and Celtic Studies, University of Galway, Ireland
| | - A P Potito
- Ryan Institute, University of Galway, Ireland; Paleoenvironmental Research Unit, School of Geography, Archaeology and Irish Studies, College of Arts, Social Sciences, and Celtic Studies, University of Galway, Ireland
| | - D O'Leary
- Ryan Institute, University of Galway, Ireland; Earth and Ocean Sciences, College of Science and Engineering, College of Arts, Social Sciences, and Celtic Studies, University of Galway, Ireland
| | - E Daly
- Ryan Institute, University of Galway, Ireland; Earth and Ocean Sciences, College of Science and Engineering, College of Arts, Social Sciences, and Celtic Studies, University of Galway, Ireland
| | - O Callery
- Ryan Institute, University of Galway, Ireland; Earth and Ocean Sciences, College of Science and Engineering, College of Arts, Social Sciences, and Celtic Studies, University of Galway, Ireland
| |
Collapse
|
4
|
Man B, Xiang X, Zhang J, Cheng G, Zhang C, Luo Y, Qin Y. Keystone Taxa and Predictive Functional Analysis of Sphagnum palustre Tank Microbiomes in Erxianyan Peatland, Central China. BIOLOGY 2022; 11:1436. [PMID: 36290340 PMCID: PMC9598613 DOI: 10.3390/biology11101436] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Revised: 09/23/2022] [Accepted: 09/28/2022] [Indexed: 06/16/2023]
Abstract
Sphagnum is a fundamental ecosystem of engineers, including more than 300 species around the world. These species host diverse microbes, either endosymbiotic or ectosymbiotic, and are key to carbon sequestration in peatland ecosystems. However, the linkages between different types of Sphagnum and the diversity and ecological functions of Sphagnum-associated microbiomes are poorly known, and so are their joint responses to ecological functions. Here, we systematically investigated endophytes in Sphagnum palustre via next-generation sequencing (NGS) techniques in the Erxianyan peatland, central China. The total bacterial microbiome was classified into 38 phyla and 55 classes, 122 orders and 490 genera. The top 8 phyla of Proteobacteria (33.69%), Firmicutes (11.94%), Bacteroidetes (9.42%), Actinobacteria (6.53%), Planctomycetes (6.37%), Gemmatimonadetes (3.05%), Acidobacteria (5.59%) and Cyanobacteria (1.71%) occupied 78.31% of total OTUs. The core microbiome of S. palustre was mainly distributed mainly in 7 phyla, 9 classes, 15 orders, 22 families and 43 known genera. There were many differences in core microbiomes compared to those in the common higher plants. We further demonstrate that the abundant functional groups have a substantial potential for nitrogen fixation, carbon cycle, nitrate metabolism, sulfate respiration and chitinolysis. These results indicate that potential ecological function of Sphagnum palustre in peatlands is partially rooted in its microbiomes, and that incorporating into functional groups of Sphagnum-associated microbiomes can promote mechanistic understanding of Sphagnum ecology in subalpine peatlands.
Collapse
Affiliation(s)
- Baiying Man
- College of Life Science, Shangrao Normal University, Shangrao 334001, China
| | - Xing Xiang
- College of Life Science, Shangrao Normal University, Shangrao 334001, China
| | - Junzhong Zhang
- Key Laboratory of Forest Disaster Warning and Control in Yunnan Higher Education Institutions, South West Forestry University, Kunming 650224, China
| | - Gang Cheng
- College of Life Science, Shangrao Normal University, Shangrao 334001, China
| | - Chao Zhang
- College of Life Science, Shangrao Normal University, Shangrao 334001, China
| | - Yang Luo
- College of Life Science, Shangrao Normal University, Shangrao 334001, China
| | - Yangmin Qin
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan 430074, China
| |
Collapse
|
5
|
Nie Y, Lau SYL, Tan X, Lu X, Liu S, Tahvanainen T, Isoda R, Ye Q, Hashidoko Y. Sphagnum capillifolium holobiont from a subarctic palsa bog aggravates the potential of nitrous oxide emissions. FRONTIERS IN PLANT SCIENCE 2022; 13:974251. [PMID: 36160957 PMCID: PMC9490422 DOI: 10.3389/fpls.2022.974251] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Accepted: 08/08/2022] [Indexed: 06/16/2023]
Abstract
Melting permafrost mounds in subarctic palsa mires are thawing under climate warming and have become a substantial source of N2O emissions. However, mechanistic insights into the permafrost thaw-induced N2O emissions in these unique habitats remain elusive. We demonstrated that N2O emission potential in palsa bogs was driven by the bacterial residents of two dominant Sphagnum mosses especially of Sphagnum capillifolium (SC) in the subarctic palsa bog, which responded to endogenous and exogenous Sphagnum factors such as secondary metabolites, nitrogen and carbon sources, temperature, and pH. SC's high N2O emission activity was linked with two classes of distinctive hyperactive N2O emitters, including Pseudomonas sp. and Enterobacteriaceae bacteria, whose hyperactive N2O emitting capability was characterized to be dominantly pH-responsive. As the nosZ gene-harboring emitter, Pseudomonas sp. SC-H2 reached a high level of N2O emissions that increased significantly with increasing pH. For emitters lacking the nosZ gene, an Enterobacteriaceae bacterium SC-L1 was more adaptive to natural acidic conditions, and N2O emissions also increased with pH. Our study revealed previously unknown hyperactive N2O emitters in Sphagnum capillifolium found in melting palsa mound environments, and provided novel insights into SC-associated N2O emissions.
Collapse
Affiliation(s)
- Yanxia Nie
- Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China
- Southern Marine Science and Engineering Guangdong Laboratory, Guangzhou, China
- Graduate School of Agriculture, Hokkaido University, Sapporo, Japan
| | - Sharon Yu Ling Lau
- Graduate School of Agriculture, Hokkaido University, Sapporo, Japan
- Sarawak Tropical Peat Research Institute, Kota Samarahan, Malaysia
| | - Xiangping Tan
- Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China
| | - Xiankai Lu
- Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China
| | - Suping Liu
- Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China
| | - Teemu Tahvanainen
- Department of Environmental and Biological Sciences, University of Eastern Finland, Joensuu, Finland
| | - Reika Isoda
- Graduate School of Agriculture, Hokkaido University, Sapporo, Japan
| | - Qing Ye
- Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China
- Southern Marine Science and Engineering Guangdong Laboratory, Guangzhou, China
| | | |
Collapse
|
6
|
Słowińska S, Słowiński M, Marcisz K, Lamentowicz M. Long-term microclimate study of a peatland in Central Europe to understand microrefugia. INTERNATIONAL JOURNAL OF BIOMETEOROLOGY 2022; 66:817-832. [PMID: 35113230 PMCID: PMC8948114 DOI: 10.1007/s00484-022-02240-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/10/2021] [Revised: 11/28/2021] [Accepted: 01/12/2022] [Indexed: 06/14/2023]
Abstract
Peatlands perform many important ecosystem functions at both the local and global scale, including hydrologic and climatic regulation. Although peatlands often act as climatic microrefugia, they have rarely been the subject of long-term microclimatic studies. In this study, we aimed to compare the local climatic conditions of a mid-forest mire to that of an open area and examine the differences in microclimates within the mire based on plant community diversity, shading, and water table depths. The peatland studied in this work was significantly cooler than the reference site, mainly due to a higher decline in nighttime air temperatures. However, the daily maximum air temperature near the ground was often higher. We also noticed that microclimates significantly differed within the studied peatland. Wet and shaded microsites were cooler than the sites having a lower water level and receiving higher amounts of solar radiation. The results of the study suggest that peatlands have locally cooler climates, and thus can serve as climate change refugia. These findings can help us interpret reconstructed data from the peat archive, and, when combined with experiments, identify tipping points for peatland ecosystems.
Collapse
Affiliation(s)
- Sandra Słowińska
- Climate Impacts Laboratory, Department of Geoecology and Climatology, Institute of Geography and Spatial Organization, Polish Academy of Sciences, Warsaw, Poland.
| | - Michał Słowiński
- Past Landscape Dynamics Laboratory, Institute of Geography and Spatial Organization, Polish Academy of Sciences, Warsaw, Poland
| | - Katarzyna Marcisz
- Climate Change Ecology Research Unit, Faculty of Geographical and Geological Sciences, Adam Mickiewicz University, Poznań, Poland
| | - Mariusz Lamentowicz
- Climate Change Ecology Research Unit, Faculty of Geographical and Geological Sciences, Adam Mickiewicz University, Poznań, Poland
| |
Collapse
|
7
|
Rubin RL, Ballantine KA, Hegberg A, Andras JP. Flooding and ecological restoration promote wetland microbial communities and soil functions on former cranberry farmland. PLoS One 2021; 16:e0260933. [PMID: 34919560 PMCID: PMC8683025 DOI: 10.1371/journal.pone.0260933] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Accepted: 11/19/2021] [Indexed: 11/25/2022] Open
Abstract
Microbial communities are early responders to wetland degradation, and instrumental players in the reversal of this degradation. However, our understanding of soil microbial community structure and function throughout wetland development remains incomplete. We conducted a survey across cranberry farms, young retired farms, old retired farms, flooded former farms, ecologically restored former farms, and natural reference wetlands with no history of cranberry farming. We investigated the relationship between the microbial community and soil characteristics that restoration intends to maximize, such as soil organic matter, cation exchange capacity and denitrification potential. Among the five treatments considered, flooded and restored sites had the highest prokaryote and microeukaryote community similarity to natural wetlands. In contrast, young retired sites had similar communities to farms, and old retired sites failed to develop wetland microbial communities or functions. Canonical analysis of principal coordinates revealed that soil variables, in particular potassium base saturation, sodium, and denitrification potential, explained 45% of the variation in prokaryote communities and 44% of the variation in microeukaryote communities, segregating soil samples into two clouds in ordination space: farm, old retired and young retired sites on one side and restored, flooded, and natural sites on the other. Heat trees revealed possible prokaryotic (Gemmatimonadetes) and microeukaryotic (Rhizaria) indicators of wetland development, along with a drop in the dominance of Nucletmycea in restored sites, a class that includes suspected mycorrhizal symbionts of the cranberry crop. Flooded sites showed the strongest evidence of wetland development, with triple the soil organic matter accumulation, double the cation exchange capacity, and seventy times the denitrification potential compared to farms. However, given that flooding does not promote any of the watershed or habitat benefits as ecological restoration, we suggest that flooding can be used to stimulate beneficial microbial communities and soil functions during the restoration waiting period, or when restoration is not an option.
Collapse
Affiliation(s)
- Rachel L. Rubin
- Department of Environmental Studies, Mount Holyoke College, South Hadley, Massachusetts United States of America
| | - Kate A. Ballantine
- Department of Environmental Studies, Mount Holyoke College, South Hadley, Massachusetts United States of America
| | - Arden Hegberg
- Department of Biology, Mount Holyoke College, South Hadley, Massachusetts, United States of America
| | - Jason P. Andras
- Department of Biology, Mount Holyoke College, South Hadley, Massachusetts, United States of America
- * E-mail:
| |
Collapse
|
8
|
Hamard S, Küttim M, Céréghino R, Jassey VEJ. Peatland microhabitat heterogeneity drives phototrophic microbe distribution and photosynthetic activity. Environ Microbiol 2021; 23:6811-6827. [PMID: 34559454 DOI: 10.1111/1462-2920.15779] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Revised: 09/16/2021] [Accepted: 09/16/2021] [Indexed: 11/26/2022]
Abstract
Phototrophic microbes are widespread in soils, but their contribution to soil carbon (C) uptake remains underexplored in most terrestrial systems, including C-accreting systems such as peatlands. Here, by means of metabarcoding and ecophysiological measurements, we examined how microbial photosynthesis and its biotic (e.g., phototrophic community structure, biomass) and abiotic drivers (e.g., Sphagnum moisture, light intensity) vary across peatland microhabitats. Using a natural gradient of microhabitat conditions from pool to forest, we show that the structure of phototrophic microbial communities shifted from a dominance of eukaryotes in pools to prokaryotes in forests. We identified five groups of co-occurring phototrophic operational taxonomic units with specific environmental preferences across the gradient. Along with such structural changes, we found that microbial C uptake was the highest in the driest and shadiest microhabitats. This study renews and improves current views on phototrophic microbes in peatlands, as the contribution of microbial photosynthesis to peatland C uptake has essentially been studied in wet microhabitats.
Collapse
Affiliation(s)
- Samuel Hamard
- Laboratoire Ecologie Fonctionnelle et Environnement, Université de Toulouse, UPS, CNRS, Toulouse, France
| | - Martin Küttim
- Institute of Ecology, School of Natural Sciences and Health, Tallinn University, Uus-Sadama 5, Tallinn, 10120, Estonia
| | - Regis Céréghino
- Laboratoire Ecologie Fonctionnelle et Environnement, Université de Toulouse, UPS, CNRS, Toulouse, France
| | - Vincent E J Jassey
- Laboratoire Ecologie Fonctionnelle et Environnement, Université de Toulouse, UPS, CNRS, Toulouse, France
| |
Collapse
|
9
|
Decomposition of peatland DOC affected by root exudates is driven by specific r and K strategic bacterial taxa. Sci Rep 2021; 11:18677. [PMID: 34548501 PMCID: PMC8455546 DOI: 10.1038/s41598-021-97698-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Accepted: 08/26/2021] [Indexed: 02/08/2023] Open
Abstract
In peatlands, decomposition of organic matter is limited by harsh environmental conditions and low decomposability of the plant material. Shifting vegetation composition from Sphagnum towards vascular plants is expected in response to climate change, which will lead to increased root exudate flux to the soil and stimulation of microbial growth and activity. We aimed to evaluate the effect of root exudates on the decomposition of recalcitrant dissolved organic carbon (DOC) and to identify microorganisms involved in this process. The exudation was mimicked by an addition of a mixture of 13C labelled compounds into the recalcitrant DOC in two realistic levels; 2% and 5% of total DOC and peatland porewater with added root exudates was incubated under controlled conditions in the lab. The early stage of incubation was characterized by a relative increase of r-strategic bacteria mainly from Gammaproteobacteria and Bacteriodetes phyla within the microbial community and their preferential use of the added compounds. At the later stage, Alphaproteobacteria and Acidobacteria members were the dominating phyla, which metabolized both the transformed 13C compounds and the recalcitrant DOC. Only higher exudate input (5% of total DOC) stimulated decomposition of recalcitrant DOC compared to non-amended control. The most important taxa with a potential to decompose complex DOC compounds were identified as: Mucilaginibacter (Bacteriodetes), Burkholderia and Pseudomonas (Gammaproteobacteria) among r-strategists and Bryocella and Candidatus Solibacter (Acidobacteria) among K-strategists. We conclude that increased root exudate inputs and their increasing C/N ratio stimulate growth and degradation potential of both r-strategic and K-strategic bacteria, which make the system more dynamic and may accelerate decomposition of peatland recalcitrant DOC.
Collapse
|
10
|
Nam S, Alday JG, Kim M, Kim H, Kim Y, Park T, Lim HS, Lee BY, Lee YK, Jung JY. The relationships of present vegetation, bacteria, and soil properties with soil organic matter characteristics in moist acidic tundra in Alaska. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 772:145386. [PMID: 33770858 DOI: 10.1016/j.scitotenv.2021.145386] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Revised: 01/19/2021] [Accepted: 01/19/2021] [Indexed: 06/12/2023]
Abstract
Soil organic matter (SOM) is related to vegetation, soil bacteria, and soil properties; however, not many studies link all these parameters simultaneously, particularly in tundra ecosystems vulnerable to climate change. Our aim was to describe the relationships between vegetation, bacteria, soil properties, and SOM composition in moist acidic tundra by integrating physical, chemical, and molecular methods. A total of 70 soil samples were collected at two different depths from 36 spots systematically arranged over an area of about 300 m × 50 m. Pyrolysis-gas chromatography/mass spectrometry and pyrosequencing of the 16S rRNA gene were used to identify the molecular compositions of the SOM and bacterial community, respectively. Vegetation and soil physicochemical properties were also measured. The sampling sites were grouped into three, based on their SOM compositions: Sphagnum moss-derived SOM, lipid-rich materials, and aromatic-rich materials. Our results show that SOM composition is spatially structured and linked to microtopography; however, the vegetation, soil properties, and bacterial community composition did not show overall spatial structuring. Simultaneously, soil properties and bacterial community composition were the main factors explaining SOM compositional variation, while vegetation had a residual effect. Verrucomicrobia and Acidobacteria were related to polysaccharides, and Chloroflexi was linked to aromatic compounds. These relationships were consistent across different hierarchical levels. Our results suggest that SOM composition at a local scale is closely linked with soil factors and the bacterial community. Comprehensive observation of ecosystem components is recommended to understand the in-situ function of bacteria and the fate of SOM in the moist acidic tundra.
Collapse
Affiliation(s)
- Sungjin Nam
- Korea Polar Research Institute, Incheon 21990, Republic of Korea
| | - Josu G Alday
- Joint Research Unit CTFC - AGROTECNIO, Av. Alcalde Rovira Roure 191, E25198 Lleida, Spain; Department of Crop and Forest Sciences, University of Lleida, Av. Alcalde Rovira Roure 191, E25198 Lleida, Spain
| | - Mincheol Kim
- Korea Polar Research Institute, Incheon 21990, Republic of Korea
| | - Hyemin Kim
- Korea Polar Research Institute, Incheon 21990, Republic of Korea
| | - Yongkang Kim
- Department of Statistics, Seoul National University, Seoul 08826, Republic of Korea
| | - Taesung Park
- Department of Statistics, Seoul National University, Seoul 08826, Republic of Korea
| | - Hyoun Soo Lim
- Department of Geological Sciences, Pusan National University, Busan 46241, Republic of Korea
| | - Bang Yong Lee
- Korea Polar Research Institute, Incheon 21990, Republic of Korea
| | - Yoo Kyung Lee
- Korea Polar Research Institute, Incheon 21990, Republic of Korea.
| | - Ji Young Jung
- Korea Polar Research Institute, Incheon 21990, Republic of Korea.
| |
Collapse
|
11
|
Robroek BJM, Martí M, Svensson BH, Dumont MG, Veraart AJ, Jassey VEJ. Rewiring of peatland plant–microbe networks outpaces species turnover. OIKOS 2021. [DOI: 10.1111/oik.07635] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Bjorn J. M. Robroek
- Aquatic Ecology and Environmental Biology, Inst. for Water and Wetland Research, Faculty of Science, Radboud Univ. Nijmegen Nijmegen the Netherlands
| | - Magalí Martí
- Thematic Studies – Environmental Change, Linköping Univ. Linköping Sweden
| | - Bo H. Svensson
- Thematic Studies – Environmental Change, Linköping Univ. Linköping Sweden
| | - Marc G. Dumont
- School of Biological Sciences, Faculty of Environmental and Life Sciences, Univ. of Southampton Southampton UK
| | - Annelies J. Veraart
- Aquatic Ecology and Environmental Biology, Inst. for Water and Wetland Research, Faculty of Science, Radboud Univ. Nijmegen Nijmegen the Netherlands
| | - Vincent E. J. Jassey
- Laboratoire d'Ecologie Fonctionnelle et Environnement, Univ. de Toulouse, CNRS Toulouse Cedex France
| |
Collapse
|
12
|
Gupta PK, Gharedaghloo B, Lynch M, Cheng J, Strack M, Charles TC, Price JS. Dynamics of microbial populations and diversity in NAPL contaminated peat soil under varying water table conditions. ENVIRONMENTAL RESEARCH 2020; 191:110167. [PMID: 32926889 DOI: 10.1016/j.envres.2020.110167] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Revised: 08/17/2020] [Accepted: 09/07/2020] [Indexed: 06/11/2023]
Abstract
Despite the risks that hydrocarbon contamination from pipeline leaks or train derailments impose on the health of peatlands in hydrocarbon production areas and transportation corridors, assessing the effect of such contaminations on the health and sustainability of peatlands has received little attention. This study investigates the impacts of hydrocarbons on peat microbial communities. Column experiments were conducted on non-aqueous phase liquid (NAPL) contaminated undisturbed peat core (0-35 cm) under static and fluctuating water table conditions. Water table fluctuations reduced residual NAPL saturation from 8.1-11.3% to 7.7-9.5%. Biodegradation of n-C8 and n-C12 along with oxidation of CH4 together produced high CO2 concentrations in the headspace. Clear patterns in dynamics in the microbial community structure were observed, with a more pronounced population growth. However, a significant loss of microbial richness was observed in contaminated columns. The result indicates that the phylum Proteobacteria benefited most from NAPL; however, their families differed between static and fluctuating water table conditions. This study established strong evidence that peat microbes and water table fluctuation can be an excellent tool for hydrocarbon removal and its control in peatlands.
Collapse
Affiliation(s)
- Pankaj Kumar Gupta
- Department of Geography and Environmental Management, University of Waterloo, Waterloo, ON, N2L 3G1, Canada.
| | - Behrad Gharedaghloo
- Department of Geography and Environmental Management, University of Waterloo, Waterloo, ON, N2L 3G1, Canada; Aquanty Inc., Waterloo, ON, N2L5C6, Canada
| | - Michael Lynch
- Department of Biology, University of Waterloo, Waterloo, ON, N2L 3G1, Canada; Metagenom Bio, Waterloo, ON, N2L 5V4, Canada
| | - Jiujun Cheng
- Department of Biology, University of Waterloo, Waterloo, ON, N2L 3G1, Canada; Metagenom Bio, Waterloo, ON, N2L 5V4, Canada
| | - Maria Strack
- Department of Geography and Environmental Management, University of Waterloo, Waterloo, ON, N2L 3G1, Canada
| | - Trevor C Charles
- Department of Biology, University of Waterloo, Waterloo, ON, N2L 3G1, Canada; Metagenom Bio, Waterloo, ON, N2L 5V4, Canada
| | - Jonathan S Price
- Department of Geography and Environmental Management, University of Waterloo, Waterloo, ON, N2L 3G1, Canada
| |
Collapse
|
13
|
L. Bräuer S, Basiliko N, M. P. Siljanen H, H. Zinder S. Methanogenic archaea in peatlands. FEMS Microbiol Lett 2020; 367:5928548. [DOI: 10.1093/femsle/fnaa172] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Accepted: 10/16/2020] [Indexed: 12/22/2022] Open
Abstract
ABSTRACT
Methane emission feedbacks in wetlands are predicted to influence global climate under climate change and other anthropogenic stressors. Herein, we review the taxonomy and physiological ecology of the microorganisms responsible for methane production in peatlands. Common in peat soils are five of the eight described orders of methanogens spanning three phyla (Euryarchaeota, Halobacterota and Thermoplasmatota). The phylogenetic affiliation of sequences found in peat suggest that members of the thus-far-uncultivated group Candidatus Bathyarchaeota (representing a fourth phylum) may be involved in methane cycling, either anaerobic oxidation of methane and/or methanogenesis, as at least a few organisms within this group contain the essential gene, mcrA, according to metagenomic data. Methanogens in peatlands are notoriously challenging to enrich and isolate; thus, much remains unknown about their physiology and how methanogen communities will respond to environmental changes. Consistent patterns of changes in methanogen communities have been reported across studies in permafrost peatland thaw where the resulting degraded feature is thermokarst. However much remains to be understood regarding methanogen community feedbacks to altered hydrology and warming in other contexts, enhanced atmospheric pollution (N, S and metals) loading and direct anthropogenic disturbances to peatlands like drainage, horticultural peat extraction, forestry and agriculture, as well as post-disturbance reclamation.
Collapse
Affiliation(s)
- Suzanna L. Bräuer
- Appalachian State University, Department of Biology, ASU Box 32027, 572 Rivers Street, Boone, NC 28608-2027 USA
| | - Nathan Basiliko
- Laurentian University, Department of Biology and the Vale Living with Lakes Centre, 935 Ramsey Lake Road, Sudbury, ON P3E 2C6, Canada
| | - Henri M. P. Siljanen
- Eastern Finland University, Department of Environmental and Biological Sciences, Biogeochemistry Research Group, Snellmania Room 4042, Yliopistonranta 1, Kuopio, 70210, Finland
| | - Stephen H. Zinder
- Cornell University, Department of Microbiology, 272 Wing Hall, Ithaca, NY 14850, USA
| |
Collapse
|
14
|
Pennanen T, Fritze H, de Boer W, Baldrian P. Editorial: special issue on the ecology of soil microorganisms. FEMS Microbiol Ecol 2019; 95:5628114. [PMID: 31738407 DOI: 10.1093/femsec/fiz154] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
| | - Hannu Fritze
- Natural Resources Institute Finland (Luke), Helsinki
| | | | | |
Collapse
|