1
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Duchesneau K, Defrenne CE, Petro C, Malhotra A, Moore JAM, Childs J, Hanson PJ, Iversen CM, Kostka JE. Responses of vascular plant fine roots and associated microbial communities to whole-ecosystem warming and elevated CO 2 in northern peatlands. New Phytol 2024; 242:1333-1347. [PMID: 38515239 DOI: 10.1111/nph.19690] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Accepted: 02/16/2024] [Indexed: 03/23/2024]
Abstract
Warming and elevated CO2 (eCO2) are expected to facilitate vascular plant encroachment in peatlands. The rhizosphere, where microbial activity is fueled by root turnover and exudates, plays a crucial role in biogeochemical cycling, and will likely at least partially dictate the response of the belowground carbon cycle to climate changes. We leveraged the Spruce and Peatland Responses Under Changing Environments (SPRUCE) experiment, to explore the effects of a whole-ecosystem warming gradient (+0°C to 9°C) and eCO2 on vascular plant fine roots and their associated microbes. We combined trait-based approaches with the profiling of fungal and prokaryote communities in plant roots and rhizospheres, through amplicon sequencing. Warming promoted self-reliance for resource uptake in trees and shrubs, while saprophytic fungi and putative chemoorganoheterotrophic bacteria utilizing plant-derived carbon substrates were favored in the root zone. Conversely, eCO2 promoted associations between trees and ectomycorrhizal fungi. Trees mostly associated with short-distance exploration-type fungi that preferentially use labile soil N. Additionally, eCO2 decreased the relative abundance of saprotrophs in tree roots. Our results indicate that plant fine-root trait variation is a crucial mechanism through which vascular plants in peatlands respond to climate change via their influence on microbial communities that regulate biogeochemical cycles.
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Affiliation(s)
- Katherine Duchesneau
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA, 30332, USA
- Center for Microbial Dynamics and Infection, Georgia Institute of Technology, Atlanta, GA, 30332, USA
| | - Camille E Defrenne
- College of Forest Resources and Environmental Science, Michigan Technological University, Houghton, MI, 49931, USA
| | - Caitlin Petro
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA, 30332, USA
- Center for Microbial Dynamics and Infection, Georgia Institute of Technology, Atlanta, GA, 30332, USA
| | - Avni Malhotra
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA, 99354, USA
| | - Jessica A M Moore
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA, 99354, USA
| | - Joanne Childs
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37830, USA
| | - Paul J Hanson
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37830, USA
- Climate Change Science Institute and Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - Colleen M Iversen
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37830, USA
- Climate Change Science Institute and Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - Joel E Kostka
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA, 30332, USA
- Center for Microbial Dynamics and Infection, Georgia Institute of Technology, Atlanta, GA, 30332, USA
- School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, GA, 30332, USA
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2
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Slate ML, Antoninka A, Bailey L, Berdugo MB, Callaghan DA, Cárdenas M, Chmielewski MW, Fenton NJ, Holland-Moritz H, Hopkins S, Jean M, Kraichak BE, Lindo Z, Merced A, Oke T, Stanton D, Stuart J, Tucker D, Coe KK. Impact of changing climate on bryophyte contributions to terrestrial water, carbon, and nitrogen cycles. New Phytol 2024. [PMID: 38659154 DOI: 10.1111/nph.19772] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Accepted: 03/22/2024] [Indexed: 04/26/2024]
Abstract
Bryophytes, including the lineages of mosses, liverworts, and hornworts, are the second-largest photoautotroph group on Earth. Recent work across terrestrial ecosystems has highlighted how bryophytes retain and control water, fix substantial amounts of carbon (C), and contribute to nitrogen (N) cycles in forests (boreal, temperate, and tropical), tundra, peatlands, grasslands, and deserts. Understanding how changing climate affects bryophyte contributions to global cycles in different ecosystems is of primary importance. However, because of their small physical size, bryophytes have been largely ignored in research on water, C, and N cycles at global scales. Here, we review the literature on how bryophytes influence global biogeochemical cycles, and we highlight that while some aspects of global change represent critical tipping points for survival, bryophytes may also buffer many ecosystems from change due to their capacity for water, C, and N uptake and storage. However, as the thresholds of resistance of bryophytes to temperature and precipitation regime changes are mostly unknown, it is challenging to predict how long this buffering capacity will remain functional. Furthermore, as ecosystems shift their global distribution in response to changing climate, the size of different bryophyte-influenced biomes will change, resulting in shifts in the magnitude of bryophyte impacts on global ecosystem functions.
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Affiliation(s)
- Mandy L Slate
- Department of Evolution, Ecology & Organismal Biology, The Ohio State University, Columbus, OH, 43210, USA
| | - Anita Antoninka
- School of Forestry, Northern Arizona University, Flagstaff, AZ, 86005, USA
| | - Lydia Bailey
- School of Forestry, Northern Arizona University, Flagstaff, AZ, 86005, USA
| | - Monica B Berdugo
- Plant Ecology and Geobotany, Department of Biology, University of Marburg, Karl-von-Frisch Str. 8, 35043, Marburg, Germany
| | - Des A Callaghan
- Bryophyte Surveys Ltd, Almondsbury, South Gloucestershire, BS32 4DU, UK
| | - Mariana Cárdenas
- Department of Ecology Evolution and Behavior, University of Minnesota, Saint Paul, MN, 55108, USA
| | | | - Nicole J Fenton
- Université du Québec en Abitibi-Témiscamingue, Rouyn-Noranda, QC, J9X 5E4, Canada
| | - Hannah Holland-Moritz
- Department of Natural Resources and the Environment, University of New Hampshire, Durham, NH, 03824, USA
| | - Samantha Hopkins
- Department of Biology, University of Western Ontario, London, ON, N6A 3K7, Canada
| | - Mélanie Jean
- Université de Moncton, Moncton, NB, E1A 3E9, Canada
| | - Bier Ekaphan Kraichak
- Department of Botany, Faculty of Science, Kasetsart University in Bangkok, Bangkok, 10900, Thailand
| | - Zoë Lindo
- Department of Biology, University of Western Ontario, London, ON, N6A 3K7, Canada
| | - Amelia Merced
- Department of Biology, University of Puerto Rico Río Piedras, San Juan, PR, 00925, USA
| | - Tobi Oke
- Wildlife Conservation Society & School of Environment & Sustainability, University of Saskatchewan, Saskatoon, SK, S7N 5C8, Canada
| | - Daniel Stanton
- Department of Ecology Evolution and Behavior, University of Minnesota, Saint Paul, MN, 55108, USA
| | - Julia Stuart
- College of Forest Resources and Environmental Science, Michigan Technological University, Houghton, MI, 49931, USA
- Mountain Planning Service Group, US Forest Service, Lakewood, CO, 80401, USA
| | - Daniel Tucker
- School of Environmental Studies, University of Victoria, Victoria, BC, V8P 5C2, Canada
| | - Kirsten K Coe
- Department of Biology, Middlebury College, Middlebury, VT, 05753, USA
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3
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Herndon E, Richardson J, Carrell AA, Pierce E, Weston D. Sulfur speciation in Sphagnum peat moss modified by mutualistic interactions with cyanobacteria. New Phytol 2024; 241:1998-2008. [PMID: 38135655 DOI: 10.1111/nph.19476] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Accepted: 11/21/2023] [Indexed: 12/24/2023]
Abstract
Peat moss (Sphagnum spp.) develops mutualistic interactions with cyanobacteria by providing carbohydrates and S compounds in exchange for N-rich compounds, potentially facilitating N inputs into peatlands. Here, we evaluate how colonization of Sphagnum angustifolium hyaline cells by Nostoc muscorum modifies S abundance and speciation at the scales of individual cells and across whole leaves. For the first time, S K-edge X-ray Absorption Spectroscopy was used to identify bulk and micron-scale S speciation across isolated cyanobacteria colonies, and in colonized and uncolonized leaves. Uncolonized leaves contained primarily reduced organic S and oxidized sulfonate- and sulfate-containing compounds. Increasing Nostoc colonization resulted in an enrichment of S and changes in speciation, with increases in sulfate relative to reduced S and sulfonate. At the scale of individual hyaline cells, colonized cells exhibited localized enrichment of reduced S surrounded by diffuse sulfonate, similar to observations of cyanobacteria colonies cultured in the absence of leaves. We infer that colonization stimulates plant S uptake and the production of sulfate-containing metabolites that are concentrated in stem tissues. Sulfate compounds that are produced in response to colonization become depleted in colonized cells where they may be converted into reduced S metabolites by cyanobacteria.
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Affiliation(s)
- Elizabeth Herndon
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37830, USA
| | | | - Alyssa A Carrell
- Biological Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37830, USA
| | - Eric Pierce
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37830, USA
| | - David Weston
- Biological Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37830, USA
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4
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Pacheco-Cancino PA, Carrillo-López RF, Sepulveda-Jauregui A, Somos-Valenzuela MA. Sphagnum mosses, the impact of disturbances and anthropogenic management actions on their ecological role in CO 2 fluxes generated in peatland ecosystems. Glob Chang Biol 2024; 30:e16972. [PMID: 37882506 DOI: 10.1111/gcb.16972] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Revised: 09/10/2023] [Accepted: 09/12/2023] [Indexed: 10/27/2023]
Abstract
Mosses of the genus Sphagnum are the dominant vegetation in most pristine peatlands in temperate and high-latitude regions. They play a crucial role in carbon sequestration, being responsible for ca. 50% of carbon accumulation through their active participation in peat formation. They have a significant influence on the dynamics of CO2 emissions due to an efficient maximum potential photosynthetic rate, lower respiration rates, and the production of a recalcitrant litter whose decomposition is gradual. However, various anthropogenic disturbances and land use management actions that favor its reestablishment have the potential to modify the dynamics of these CO2 emissions. Therefore, the objective of this review is to discuss the role of Sphagnum in CO2 emissions generated in peatland ecosystems, and to understand the impacts of anthropogenic practices favorable and detrimental to Sphagnum on these emissions. Based on our review, increased Sphagnum cover reduces CO2 emissions and fosters C sequestration, but drainage transforms peatlands dominated by Sphagnum into a persistent source of CO2 due to lower gross primary productivity of the moss and increased respiration rates. Sites with moss removal used as donor material for peatland restoration emit twice as much CO2 as adjacent undisturbed natural sites, and those with commercial Sphagnum extraction generate almost neutral CO2 emissions, yet both can recover their sink status in the short term. The reintroduction of fragments and natural recolonization of Sphagnum in transitional peatlands, can reduce emissions, recover, or increase the CO2 sink function in the short and medium term. Furthermore, Sphagnum paludiculture is seen as a sustainable alternative for the use of transitional peatlands, allowing moss production strips to become CO2 sink, however, it is necessary to quantify the emissions of all the components of the field of production (ditches, causeway), and the biomass harvested from the moss to establish a final closing balance of C.
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Affiliation(s)
- Patricio A Pacheco-Cancino
- Department of Agricultural Sciences and Natural Resources, Faculty of Agricultural and Environmental Sciences, Universidad de La Frontera, Temuco, Región de La Araucanía, Chile
- Doctorate in Agri-Food and Environmental Sciences, Faculty of Agricultural and Environmental Sciences, Universidad de La Frontera, Temuco, Región de La Araucanía, Chile
| | - Rubén F Carrillo-López
- Department of Agricultural Sciences and Natural Resources, Faculty of Agricultural and Environmental Sciences, Universidad de La Frontera, Temuco, Región de La Araucanía, Chile
| | - Armando Sepulveda-Jauregui
- Gaia Antarctic Research Center (CIGA), Universidad de Magallanes, Punta Arenas, Región de Magallanes y Antartica Chilena, Chile
- Network for Extreme Environment Research (NEXER), Universidad de Magallanes, Punta Arenas, Región de Magallanes y Antartica Chilena, Chile
| | - Marcelo A Somos-Valenzuela
- Department of Forest Sciences, Faculty of Agricultural and Environmental Science, Universidad de La Frontera, Temuco, Región de La Araucanía, Chile
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Mironov VL. Geomagnetic Anomaly in the Growth Response of Peat Moss Sphagnum riparium to Temperature. Plants (Basel) 2023; 13:48. [PMID: 38202356 PMCID: PMC10780739 DOI: 10.3390/plants13010048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Revised: 12/03/2023] [Accepted: 12/20/2023] [Indexed: 01/12/2024]
Abstract
Temperature plays an essential role in a plant's life. The current investigation reveals that photoreceptors, whose activity is affected by the geomagnetic field, are a critical element of its perception. This knowledge suggests that plants' responses to temperature could shift in different geomagnetic conditions. To test this hypothesis, we studied the change in the growth response of the peat moss Sphagnum riparium to temperature with a gradual increase in the geomagnetic Kp index. Growth data for this species were collected from Karelian mires by detailed monitoring over eight full growing seasons. The growth of 209,490 shoots was measured and 1439 growth rates were obtained for this period. The analysis showed a strong positive dependence of sphagnum growth on temperature (r = 0.58; n = 1439; P = 1.7 × 10-119), which is strongest in the Kp range from 0.87 to 1.61 (r = 0.65; n = 464; P = 4.5 × 10-58). This Kp interval is clearer after removing the seasonal contributions from the growth rate and temperature and is preserved when diurnal temperature is used. Our results are consistent with the hypothesis and show the unknown contribution of the geomagnetic field to the temperature responses of plants.
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Affiliation(s)
- Victor L Mironov
- Institute of Biology of the Karelian Research, Centre of the Russian Academy of Sciences, Pushkinskaya St. 11, 185910 Petrozavodsk, Russia
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6
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Ofiti NOE, Schmidt MWI, Abiven S, Hanson PJ, Iversen CM, Wilson RM, Kostka JE, Wiesenberg GLB, Malhotra A. Climate warming and elevated CO 2 alter peatland soil carbon sources and stability. Nat Commun 2023; 14:7533. [PMID: 37985767 PMCID: PMC10662476 DOI: 10.1038/s41467-023-43410-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2023] [Accepted: 11/09/2023] [Indexed: 11/22/2023] Open
Abstract
Peatlands are an important carbon (C) reservoir storing one-third of global soil organic carbon (SOC), but little is known about the fate of these C stocks under climate change. Here, we examine the impact of warming and elevated atmospheric CO2 concentration (eCO2) on the molecular composition of SOC to infer SOC sources (microbe-, plant- and fire-derived) and stability in a boreal peatland. We show that while warming alone decreased plant- and microbe-derived SOC due to enhanced decomposition, warming combined with eCO2 increased plant-derived SOC compounds. We further observed increasing root-derived inputs (suberin) and declining leaf/needle-derived inputs (cutin) into SOC under warming and eCO2. The decline in SOC compounds with warming and gains from new root-derived C under eCO2, suggest that warming and eCO2 may shift peatland C budget towards pools with faster turnover. Together, our results indicate that climate change may increase inputs and enhance decomposition of SOC potentially destabilising C storage in peatlands.
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Affiliation(s)
- Nicholas O E Ofiti
- Department of Geography, University of Zurich, Zurich, Switzerland.
- CEREEP-Ecotron Ile De France, ENS, CNRS, PSL Research University, Saint-Pierre-lès-Nemours, France.
| | | | - Samuel Abiven
- CEREEP-Ecotron Ile De France, ENS, CNRS, PSL Research University, Saint-Pierre-lès-Nemours, France
- Laboratoire de Géologie, Département de Géosciences, Ecole normale supérieure (ENS), Paris, France
| | - Paul J Hanson
- Environmental Sciences Division and Climate Change Science Institute, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - Colleen M Iversen
- Environmental Sciences Division and Climate Change Science Institute, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - Rachel M Wilson
- Department of Earth, Ocean and Atmospheric Sciences, Florida State University, Tallahassee, FL, USA
| | - Joel E Kostka
- School of Biological Sciences and School of Earth and Atmospheric Sciences, Center for Microbial Dynamics and Infection, Georgia Institute of Technology, Atlanta, GA, USA
| | | | - Avni Malhotra
- Department of Geography, University of Zurich, Zurich, Switzerland
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA, USA
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7
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Roth SW, Griffiths NA, Kolka RK, Oleheiser KC, Carrell AA, Klingeman DM, Seibert A, Chanton JP, Hanson PJ, Schadt CW. Elevated temperature alters microbial communities, but not decomposition rates, during 3 years of in situ peat decomposition. mSystems 2023; 8:e0033723. [PMID: 37819069 PMCID: PMC10654087 DOI: 10.1128/msystems.00337-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2023] [Accepted: 08/29/2023] [Indexed: 10/13/2023] Open
Abstract
IMPORTANCE Microbial community changes in response to climate change drivers have the potential to alter the trajectory of important ecosystem functions. In this paper, we show that while microbial communities in peatland systems responded to manipulations of temperature and CO2 concentrations, these changes were not associated with similar responses in peat decomposition rates over 3 years. It is unclear however from our current studies whether this functional resiliency over 3 years will continue over the longer time scales relevant to peatland ecosystem functions.
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Affiliation(s)
- Spencer W. Roth
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA
| | - Natalie A. Griffiths
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA
- Climate Change Science Institute, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA
| | - Randall K. Kolka
- Northern Research Station, USDA Forest Service, Grand Rapids, Minnesota, USA
| | - Keith C. Oleheiser
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA
- Climate Change Science Institute, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA
| | - Alyssa A. Carrell
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA
| | - Dawn M. Klingeman
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA
| | - Angela Seibert
- Department of Geosciences, Boise State University, Boise, Idaho, USA
| | - Jeffrey P. Chanton
- Department of Earth, Ocean, and Atmospheric Science, Florida State University, Tallahassee, Florida, USA
| | - Paul J. Hanson
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA
- Climate Change Science Institute, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA
| | - Christopher W. Schadt
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA
- Climate Change Science Institute, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA
- Department of Microbiology, University of Tennessee, Knoxville, Tennessee, USA
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Norby RJ, Baxter T, Živković T, Weston DJ. Shading contributes to Sphagnum decline in response to warming. Ecol Evol 2023; 13:e10542. [PMID: 37732286 PMCID: PMC10507575 DOI: 10.1002/ece3.10542] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Revised: 08/28/2023] [Accepted: 09/06/2023] [Indexed: 09/22/2023] Open
Abstract
Experimental warming of an ombrotrophic bog in northern Minnesota has caused a rapid decline in the productivity and areal cover of Sphagnum mosses, affecting whole-ecosystem carbon balance and biogeochemistry. Direct effects of elevated temperature and the attendant drying are most likely the primary cause of the effects on Sphagnum, but there may also be responses to the increased shading from shrubs, which increased with increasing temperature. To evaluate the independent effects of reduction in light availability and deposition of shrub litter on Sphagnum productivity, small plots with shrubs removed were laid out adjacent to the warming experiment on hummocks and hollows in three blocks and with five levels of shading. Four plots were covered with neutral density shade cloth to simulate shading from shrubs of 30%-90% reduction in light; one plot was left open. Growth of Sphagnum angustifolium/fallax and S. divinum declined linearly with increasing shade in hollows, but there was no response to shade on hummocks, where higher irradiance in the open plots may have been inhibitory. Shading caused etiolation of Sphagnum-they were thin and spindly under the deepest shade. A dense mat of shrub litter, corresponding to the amount of shrub litter produced in response to warming, did not inhibit Sphagnum growth or cause increases in potentially toxic base cations. CO2 exchange and chlorophyll-a fluorescence of S. angustifolium/fallax from the 30% and 90% shade cloth plots were measured in the laboratory. Light response curves indicate that maximal light saturated photosynthesis was 42% greater for S. angustifolium/fallax grown under 30% shade cloth relative to plants grown under 90% shade cloth. The response of Sphagnum growth in response to increasing shade is consistent with the hypothesis that increased shade resulting from shrub expansion in response to experimental warming contributed to reduced Sphagnum growth.
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Affiliation(s)
- Richard J Norby
- Environmental Sciences Division Oak Ridge National Laboratory Oak Ridge Tennessee USA
- Department of Ecology and Evolutionary Biology University of Tennessee Knoxville Tennessee USA
| | - Taylor Baxter
- Department of Ecology and Evolutionary Biology University of Tennessee Knoxville Tennessee USA
| | - Tatjana Živković
- Department of Biology Dalhousie University Halifax Nova Scotia Canada
- Biological Sciences Division Oak Ridge National Laboratory Oak Ridge Tennessee USA
| | - David J Weston
- Biological Sciences Division Oak Ridge National Laboratory Oak Ridge Tennessee USA
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9
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Schädel C, Seyednasrollah B, Hanson PJ, Hufkens K, Pearson KJ, Warren JM, Richardson AD. Using long-term data from a whole ecosystem warming experiment to identify best spring and autumn phenology models. Plant Environ Interact 2023; 4:188-200. [PMID: 37583877 PMCID: PMC10423976 DOI: 10.1002/pei3.10118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Revised: 06/05/2023] [Accepted: 06/18/2023] [Indexed: 08/17/2023]
Abstract
Predicting vegetation phenology in response to changing environmental factors is key in understanding feedbacks between the biosphere and the climate system. Experimental approaches extending the temperature range beyond historic climate variability provide a unique opportunity to identify model structures that are best suited to predicting phenological changes under future climate scenarios. Here, we model spring and autumn phenological transition dates obtained from digital repeat photography in a boreal Picea-Sphagnum bog in response to a gradient of whole ecosystem warming manipulations of up to +9°C, using five years of observational data. In spring, seven equally best-performing models for Larix utilized the accumulation of growing degree days as a common driver for temperature forcing. For Picea, the best two models were sequential models requiring winter chilling before spring forcing temperature is accumulated. In shrub, parallel models with chilling and forcing requirements occurring simultaneously were identified as the best models. Autumn models were substantially improved when a CO2 parameter was included. Overall, the combination of experimental manipulations and multiple years of observations combined with variation in weather provided the framework to rule out a large number of candidate models and to identify best spring and autumn models for each plant functional type.
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Affiliation(s)
- Christina Schädel
- Center for Ecosystem Science and SocietyNorthern Arizona UniversityFlagstaffArizonaUSA
- Woodwell Climate Research CenterFalmouthMassachusettsUSA
| | - Bijan Seyednasrollah
- School of Informatics, Computing and Cyber SystemsNorthern Arizona UniversityFlagstaffArizonaUSA
| | - Paul J. Hanson
- Environmental Sciences Division and Climate Change Science InstituteOak Ridge National LaboratoryOak RidgeTennesseeUSA
| | | | - Kyle J. Pearson
- Environmental Sciences Division and Climate Change Science InstituteOak Ridge National LaboratoryOak RidgeTennesseeUSA
| | - Jeffrey M. Warren
- Environmental Sciences Division and Climate Change Science InstituteOak Ridge National LaboratoryOak RidgeTennesseeUSA
| | - Andrew D. Richardson
- Center for Ecosystem Science and SocietyNorthern Arizona UniversityFlagstaffArizonaUSA
- School of Informatics, Computing and Cyber SystemsNorthern Arizona UniversityFlagstaffArizonaUSA
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10
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Song T, Liu Y, Kolton M, Wilson RM, Keller JK, Rolando JL, Chanton JP, Kostka JE. Porewater constituents inhibit microbially mediated greenhouse gas production (GHG) and regulate the response of soil organic matter decomposition to warming in anoxic peat from a Sphagnum-dominated bog. FEMS Microbiol Ecol 2023; 99:fiad060. [PMID: 37280172 DOI: 10.1093/femsec/fiad060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2022] [Revised: 05/16/2023] [Accepted: 06/05/2023] [Indexed: 06/08/2023] Open
Abstract
Northern peatlands store approximately one-third of terrestrial soil carbon. Climate warming is expected to stimulate the microbially mediated degradation of peat soil organic matter (SOM), leading to increasing greenhouse gas (GHG; carbon dioxide, CO2; methane, CH4) production and emission. Porewater dissolved organic matter (DOM) plays a key role in SOM decomposition; however, the mechanisms controlling SOM decomposition and its response to warming remain unclear. The temperature dependence of GHG production and microbial community dynamics were investigated in anoxic peat from a Sphagnum-dominated peatland. In this study, peat decomposition, which was quantified by GHG production and carbon substrate utilization is limited by terminal electron acceptors (TEA) and DOM, and these controls of microbially mediated SOM degradation are temperature-dependent. Elevated temperature led to a slight decrease in microbial diversity, and stimulated the growth of specific methanotrophic and syntrophic taxa. These results confirm that DOM is a major driver of decomposition in peatland soils contains inhibitory compounds, but the inhibitory effect is alleviated by warming.
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Affiliation(s)
- Tianze Song
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA 30332, United States
| | - Yutong Liu
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA 30332, United States
- Department of Civil & Environmental Engineering, Pennsylvania State University, University Park, University Park, PA 16802, United States
| | - Max Kolton
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA 30332, United States
- French Associates Institute for Agriculture and Biotechnology of Drylands, Ben-Gurion, University of the Negev, Beer Sheva, 8499000, Israel
| | - Rachel M Wilson
- Department of Earth, Ocean & Atmospheric Science, Florida State University, Tallahassee, FL 32304, United States
| | - Jason K Keller
- Schmid College of Science and Technology, Chapman University, 1 University Dr, Orange, CA 92866, United States
| | - Jose L Rolando
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA 30332, United States
| | - Jeffrey P Chanton
- Department of Earth, Ocean & Atmospheric Science, Florida State University, Tallahassee, FL 32304, United States
| | - Joel E Kostka
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA 30332, United States
- School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, GA 30318, United States
- Center for Microbial Dynamics and Infection, Georgia Institute of Technology, Atlanta, GA 30332, United States
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11
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Petro C, Carrell AA, Wilson RM, Duchesneau K, Noble-Kuchera S, Song T, Iversen CM, Childs J, Schwaner G, Chanton JP, Norby RJ, Hanson PJ, Glass JB, Weston DJ, Kostka JE. Climate drivers alter nitrogen availability in surface peat and decouple N 2 fixation from CH 4 oxidation in the Sphagnum moss microbiome. Glob Chang Biol 2023; 29:3159-3176. [PMID: 36999440 DOI: 10.1111/gcb.16651] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Accepted: 12/20/2022] [Indexed: 05/03/2023]
Abstract
Peat mosses (Sphagnum spp.) are keystone species in boreal peatlands, where they dominate net primary productivity and facilitate the accumulation of carbon in thick peat deposits. Sphagnum mosses harbor a diverse assemblage of microbial partners, including N2 -fixing (diazotrophic) and CH4 -oxidizing (methanotrophic) taxa that support ecosystem function by regulating transformations of carbon and nitrogen. Here, we investigate the response of the Sphagnum phytobiome (plant + constituent microbiome + environment) to a gradient of experimental warming (+0°C to +9°C) and elevated CO2 (+500 ppm) in an ombrotrophic peatland in northern Minnesota (USA). By tracking changes in carbon (CH4 , CO2 ) and nitrogen (NH4 -N) cycling from the belowground environment up to Sphagnum and its associated microbiome, we identified a series of cascading impacts to the Sphagnum phytobiome triggered by warming and elevated CO2 . Under ambient CO2 , warming increased plant-available NH4 -N in surface peat, excess N accumulated in Sphagnum tissue, and N2 fixation activity decreased. Elevated CO2 offset the effects of warming, disrupting the accumulation of N in peat and Sphagnum tissue. Methane concentrations in porewater increased with warming irrespective of CO2 treatment, resulting in a ~10× rise in methanotrophic activity within Sphagnum from the +9°C enclosures. Warming's divergent impacts on diazotrophy and methanotrophy caused these processes to become decoupled at warmer temperatures, as evidenced by declining rates of methane-induced N2 fixation and significant losses of keystone microbial taxa. In addition to changes in the Sphagnum microbiome, we observed ~94% mortality of Sphagnum between the +0°C and +9°C treatments, possibly due to the interactive effects of warming on N-availability and competition from vascular plant species. Collectively, these results highlight the vulnerability of the Sphagnum phytobiome to rising temperatures and atmospheric CO2 concentrations, with significant implications for carbon and nitrogen cycling in boreal peatlands.
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Affiliation(s)
- Caitlin Petro
- Center for Microbial Dynamics and Infection, School of Biological Sciences, Georgia Institute of Technology, Atlanta, Georgia, USA
| | - Alyssa A Carrell
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA
| | - Rachel M Wilson
- Department of Earth, Ocean and Atmospheric Science, Florida State University, Tallahassee, Florida, USA
| | - Katherine Duchesneau
- Center for Microbial Dynamics and Infection, School of Biological Sciences, Georgia Institute of Technology, Atlanta, Georgia, USA
| | - Sekou Noble-Kuchera
- Center for Microbial Dynamics and Infection, School of Biological Sciences, Georgia Institute of Technology, Atlanta, Georgia, USA
| | - Tianze Song
- Center for Microbial Dynamics and Infection, School of Biological Sciences, Georgia Institute of Technology, Atlanta, Georgia, USA
| | - Colleen M Iversen
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA
- Climate Change Science Institute, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA
| | - Joanne Childs
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA
- Climate Change Science Institute, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA
| | - Geoff Schwaner
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA
- Climate Change Science Institute, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA
| | - Jeffrey P Chanton
- Department of Earth, Ocean and Atmospheric Science, Florida State University, Tallahassee, Florida, USA
| | - Richard J Norby
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA
- Climate Change Science Institute, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA
- Department of Ecology & Evolutionary Biology, University of Tennessee, Knoxville, Tennessee, USA
| | - Paul J Hanson
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA
- Climate Change Science Institute, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA
| | - Jennifer B Glass
- School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, Georgia, USA
| | - David J Weston
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA
- Climate Change Science Institute, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA
| | - Joel E Kostka
- Center for Microbial Dynamics and Infection, School of Biological Sciences, Georgia Institute of Technology, Atlanta, Georgia, USA
- School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, Georgia, USA
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12
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Kolari THM, Tahvanainen T. Inference of future bog succession trajectory from spatial chronosequence of changing aapa mires. Ecol Evol 2023; 13:e9988. [PMID: 37082320 PMCID: PMC10111175 DOI: 10.1002/ece3.9988] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Revised: 03/16/2023] [Accepted: 03/24/2023] [Indexed: 04/22/2023] Open
Abstract
Climate change-driven vegetation changes can alter the ecosystem functions of northern peatlands. Several case studies have documented fen-to-bog transition (FBT) over recent decades, which can have major implications, as increased bog growth would likely cause cooling feedback. However, studies beyond individual cases are missing to infer if a common trajectory or many alternatives of FBT are in progress. We explored plant community and hydrology patterns during FBT of 23 boreal aapa mire complexes in Finland. We focused on mires where comparisons of historical (1940-1970) and new (2017-2019) aerial photographs indicated an expansion of Sphagnum-dominated zones. Vegetation plot and water chemistry data were collected from string-flark fens, transition zones with indications of Sphagnum increase, and bog zones; thus, in a chronosequence with a decadal time span. We ask, is there a common trajectory or many alternatives of FBT in progress, and what are the main characteristics (species and traits) of transitional plant communities? We found a pattern of fen-bog transitions via an increase in Sphagnum sect. Cuspidata (mainly S. majus and S. balticum), indicating a consistently high water table. Indicators only of transitional communities were scarce (Sphagnum lindbergii), but FBT had apparently facilitated shallow-rooted aerenchymatous vascular plants, especially Scheuchzeria palustris. Water pH consistently reflected the chronosequence with averages of 4.2, 3.9, and 3.8, from fen to transition and bog zones. Due to weak minerotrophy of string-flark fens, species richness increased towards bogs, but succession led to reduced beta diversity and homogenization among bog sites. Decadal chronosequence suggested a future fen-bog transition through a wet phase, instead of a drying trend. Transitional poor-fen vegetation was characterized by the abundance of Sphagnum lindbergii, S. majus, and Scheuchzeria palustris. Sphagnum mosses likely benefit from longer growing seasons and consistently wet and acidic conditions of aapa mires.
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Affiliation(s)
- Tiina H. M. Kolari
- Department of Environmental and Biological SciencesUniversity of Eastern FinlandP.O. Box 111JoensuuFI‐80101Finland
| | - Teemu Tahvanainen
- Department of Environmental and Biological SciencesUniversity of Eastern FinlandP.O. Box 111JoensuuFI‐80101Finland
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13
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Porada P, Bader MY, Berdugo MB, Colesie C, Ellis CJ, Giordani P, Herzschuh U, Ma Y, Launiainen S, Nascimbene J, Petersen I, Raggio Quílez J, Rodríguez-Caballero E, Rousk K, Sancho LG, Scheidegger C, Seitz S, Van Stan JT, Veste M, Weber B, Weston DJ. A research agenda for nonvascular photoautotrophs under climate change. New Phytol 2023; 237:1495-1504. [PMID: 36511294 DOI: 10.1111/nph.18631] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Accepted: 11/17/2022] [Indexed: 06/17/2023]
Abstract
Nonvascular photoautotrophs (NVP), including bryophytes, lichens, terrestrial algae, and cyanobacteria, are increasingly recognized as being essential to ecosystem functioning in many regions of the world. Current research suggests that climate change may pose a substantial threat to NVP, but the extent to which this will affect the associated ecosystem functions and services is highly uncertain. Here, we propose a research agenda to address this urgent question, focusing on physiological and ecological processes that link NVP to ecosystem functions while also taking into account the substantial taxonomic diversity across multiple ecosystem types. Accordingly, we developed a new categorization scheme, based on microclimatic gradients, which simplifies the high physiological and morphological diversity of NVP and world-wide distribution with respect to several broad habitat types. We found that habitat-specific ecosystem functions of NVP will likely be substantially affected by climate change, and more quantitative process understanding is required on: (1) potential for acclimation; (2) response to elevated CO2 ; (3) role of the microbiome; and (4) feedback to (micro)climate. We suggest an integrative approach of innovative, multimethod laboratory and field experiments and ecophysiological modelling, for which sustained scientific collaboration on NVP research will be essential.
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Affiliation(s)
- Philipp Porada
- Ecological Modelling, Universität Hamburg, Ohnhorststr. 18, 22609, Hamburg, Germany
| | - Maaike Y Bader
- Ecological Plant Geography, University of Marburg, Deutschhausstr. 10, 35032, Marburg, Germany
| | - Monica B Berdugo
- Ecological Plant Geography, University of Marburg, Deutschhausstr. 10, 35032, Marburg, Germany
| | - Claudia Colesie
- School of Geosciences, University of Edinburgh, Edinburgh, EH9 3JW, UK
| | | | | | - Ulrike Herzschuh
- Polar Terrestrial Environmental Systems, Alfred Wegener Institute, Telegrafenberg A45, 14473, Potsdam, Germany
| | - Yunyao Ma
- Ecological Modelling, Universität Hamburg, Ohnhorststr. 18, 22609, Hamburg, Germany
| | - Samuli Launiainen
- Ecosystems and Modeling, Natural Resources Institute Finland (Luke), Latokartanonkaari 9, 00790, Helsinki, Finland
| | - Juri Nascimbene
- BIOME Lab, Department of Biological, Geological and Environmental Sciences, Alma Mater Studiorum University of Bologna, 40126, Bologna, Italy
| | - Imke Petersen
- Ecological Modelling, Universität Hamburg, Ohnhorststr. 18, 22609, Hamburg, Germany
| | - José Raggio Quílez
- Department of Pharmacology, Pharmacognosy and Botany, Universidad Complutense de Madrid, E-28040, Madrid, Spain
| | | | - Kathrin Rousk
- Department of Biology, University of Copenhagen, Universitetsparken 15, 2100, København, Denmark
| | - Leopoldo G Sancho
- Department of Pharmacology, Pharmacognosy and Botany, Universidad Complutense de Madrid, E-28040, Madrid, Spain
| | - Christoph Scheidegger
- Biodiversity and Conservation Biology, Eidg. Forschungsanstalt WSL, Zürcherstr. 111, 8903, Birmensdorf, Switzerland
| | - Steffen Seitz
- Soil Science and Geomorphology, University of Tübingen, Rümelinstr. 19-23, 72070, Tübingen, Germany
| | - John T Van Stan
- Department of Biological, Geological, and Environmental Sciences, Cleveland State University, 2121 Euclid Ave., Cleveland, OH, 44115, USA
| | - Maik Veste
- Institute of Environmental Sciences, Brandenburgische Technische Universität Cottbus-Senftenberg, Konrad-Wachsmann-Allee 6, 03046, Cottbus, Germany
| | - Bettina Weber
- Division of Plant Sciences, Institute for Biology, University of Graz, Holteigasse 6, A-8010, Graz, Austria
- Multiphase Chemistry Department, Max Planck Institute for Chemistry, Hahn-Meitner-Weg 1, 55128, Mainz, Germany
| | - David J Weston
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
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14
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Meyer AR, Valentin M, Liulevicius L, McDonald TR, Nelsen MP, Pengra J, Smith RJ, Stanton D. Climate warming causes photobiont degradation and carbon starvation in a boreal climate sentinel lichen. Am J Bot 2023; 110:e16114. [PMID: 36462151 DOI: 10.1002/ajb2.16114] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Revised: 11/23/2022] [Accepted: 11/23/2022] [Indexed: 06/17/2023]
Abstract
PREMISE The long-term potential for acclimation by lichens to changing climates is poorly known, despite their prominent roles in forested ecosystems. Although often considered "extremophiles," lichens may not readily acclimate to novel climates well beyond historical norms. In a previous study (Smith et al., 2018), Evernia mesomorpha transplants in a whole-ecosystem climate change experiment showed drastic mass loss after 1 yr of warming and drying; however, the causes of this mass loss were not addressed. METHODS We examined the causes of this warming-induced mass loss by measuring physiological, functional, and reproductive attributes of lichen transplants. RESULTS Severe loss of mass and physiological function occurred above +2°C of experimental warming. Loss of algal symbionts ("bleaching") and turnover in algal community compositions increased with temperature and were the clearest impacts of experimental warming. Enhanced CO2 had no significant physiological or symbiont composition effects. The functional loss of algal photobionts led to significant loss of mass and specific thallus mass (STM), which in turn reduced water-holding capacity (WHC). Although algal genotypes remained detectable in thalli exposed to higher stress, within-thallus photobiont communities shifted in composition toward greater diversity. CONCLUSIONS The strong negative impacts of warming and/or lower humidity on Evernia mesomorpha were driven by a loss of photobiont activity. Analogous to the effects of climate change on corals, the balance of symbiont carbon metabolism in lichens is central to their resilience to changing conditions.
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Affiliation(s)
- Abigail R Meyer
- Ecology, Evolution and Behavior, University of Minnesota, Saint Paul, Minnesota, 55108, USA
| | - Maria Valentin
- Ecology, Evolution and Behavior, University of Minnesota, Saint Paul, Minnesota, 55108, USA
| | - Laima Liulevicius
- Ecology, Evolution and Behavior, University of Minnesota, Saint Paul, Minnesota, 55108, USA
| | - Tami R McDonald
- Biology Department, Saint Catherine University, Saint Paul, Minnesota, 55105, USA
| | - Matthew P Nelsen
- The Field Museum, Negaunee Integrative Research Center and Grainger Bioinformatics Center, Chicago, Illinois, 60605, USA
| | - Jean Pengra
- Macalester College, Saint Paul, Minnesota, 55105, USA
| | - Robert J Smith
- Air Resource Management Program, USDA Forest Service Headquarters, Biological and Physical Resources, Washington, DC, 20250, USA
| | - Daniel Stanton
- Ecology, Evolution and Behavior, University of Minnesota, Saint Paul, Minnesota, 55108, USA
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15
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Sytiuk A, Hamard S, Céréghino R, Dorrepaal E, Geissel H, Küttim M, Lamentowicz M, Tuittila ES, Jassey VEJ. Linkages between Sphagnum metabolites and peatland CO 2 uptake are sensitive to seasonality in warming trends. New Phytol 2023; 237:1164-1178. [PMID: 36336780 PMCID: PMC10108112 DOI: 10.1111/nph.18601] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Accepted: 10/31/2022] [Indexed: 06/16/2023]
Abstract
Plants produce a wide diversity of metabolites. Yet, our understanding of how shifts in plant metabolites as a response to climate change feedback on ecosystem processes remains scarce. Here, we test to what extent climate warming shifts the seasonality of metabolites produced by Sphagnum mosses, and what are the consequences of these shifts for peatland C uptake. We used a reciprocal transplant experiment along a climate gradient in Europe to simulate climate change. We evaluated the responses of primary and secondary metabolites in five Sphagnum species and related their responses to gross ecosystem productivity (GEP). When transplanted to a warmer climate, Sphagnum species showed consistent responses to warming, with an upregulation of either their primary or secondary metabolite according to seasons. Moreover, these shifts were correlated to changes in GEP, especially in spring and autumn. Our results indicate that the Sphagnum metabolome is very plastic and sensitive to warming. We also show that warming-induced changes in the seasonality of Sphagnum metabolites have consequences on peatland GEP. Our findings demonstrate the capacity for plant metabolic plasticity to impact ecosystem C processes and reveal a further mechanism through which Sphagnum could shape peatland responses to climate change.
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Affiliation(s)
- Anna Sytiuk
- Laboratoire Ecologie Fonctionnelle et Environnement (LEFE)Université Paul Sabatier, CNRSF‐31000ToulouseFrance
| | - Samuel Hamard
- Laboratoire Ecologie Fonctionnelle et Environnement (LEFE)Université Paul Sabatier, CNRSF‐31000ToulouseFrance
| | - Régis Céréghino
- Laboratoire Ecologie Fonctionnelle et Environnement (LEFE)Université Paul Sabatier, CNRSF‐31000ToulouseFrance
| | - Ellen Dorrepaal
- Department of Ecology and Environmental Science, Climate Impacts Research CentreUmeå UniversitySE‐981 07AbiskoSweden
| | - Honorine Geissel
- Laboratoire Ecologie Fonctionnelle et Environnement (LEFE)Université Paul Sabatier, CNRSF‐31000ToulouseFrance
| | - Martin Küttim
- Institute of Ecology, School of Natural Sciences and HealthTallinn UniversityUus‐Sadama 510120TallinnEstonia
| | - Mariusz Lamentowicz
- Climate Change Ecology Research Unit, Faculty of Geographical and Geological SciencesAdam Mickiewicz University in PoznańBogumiła Krygowskiego 1061‐680PoznańPoland
| | - Eeva Stiina Tuittila
- School of Forest SciencesUniversity of Eastern FinlandJoensuu CampusFI‐80100JoensuuFinland
| | - Vincent E. J. Jassey
- Laboratoire Ecologie Fonctionnelle et Environnement (LEFE)Université Paul Sabatier, CNRSF‐31000ToulouseFrance
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16
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Lhosmot A, Jacotot A, Steinmann M, Binet P, Toussaint M, Gogo S, Gilbert D, Coffinet S, Laggoun-deffarge F, Bertrand G. Biotic and Abiotic Control Over Diurnal CH4 Fluxes in a Temperate Transitional Poor Fen Ecosystem. Ecosystems 2022. [DOI: 10.1007/s10021-022-00809-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
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17
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Ma XY, Xu H, Cao ZY, Shu L, Zhu RL. Will climate change cause the global peatland to expand or contract? Evidence from the habitat shift pattern of Sphagnum mosses. Glob Chang Biol 2022; 28:6419-6432. [PMID: 35900846 DOI: 10.1111/gcb.16354] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Accepted: 07/04/2022] [Indexed: 06/15/2023]
Abstract
Peatlands play a crucial role in the global carbon cycle. Sphagnum mosses (peat mosses) are considered to be the peatland ecosystem engineers and contribute to the carbon accumulation in the peatland ecosystems. As cold-adapted species, the dominance of Sphagnum mosses in peatlands will be threatened by climate warming. The response of Sphagnum mosses to climate change is closely related to the future trajectory of carbon fluxes in peatlands. However, the impact of climate change on the habitat suitability of Sphagnum mosses on a global scale is poorly understood. To predict the potential impact of climate change on the global distribution of Sphagnum mosses, we used the MaxEnt model to predict the potential geographic distribution of six Sphagnum species that dominate peatlands in the future (2050 and 2070) under two greenhouse gas emission scenarios (SSP1-2.6 and SSP5-8.5). The results show that the mean temperature of the coldest quarter, precipitation of the driest month, and topsoil calcium carbonate are the main factors affecting the habitat availability of Sphagnum mosses. As the climate warms, Sphagnum mosses tend to migrate northward. The suitable habitat and abundance of Sphagnum mosses increase extensively in the high-latitude boreal peatland (north of 50°N) and decrease on a large scale beyond the high-latitude boreal peatland. The southern edge of boreal peatlands would experience the greatest decline in the suitable habitat and richness of Sphagnum mosses with the temperature rising and would be a risk area for the transition from carbon sink to carbon source. The spatial-temporal pattern changes of Sphagnum mosses simulated in this study provide a reference for the development of management and conservation strategies for Sphagnum bogs.
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Affiliation(s)
- Xiao-Ying Ma
- Bryology Laboratory, School of Life Sciences, East China Normal University, Shanghai, China
| | - Hao Xu
- Bryology Laboratory, School of Life Sciences, East China Normal University, Shanghai, China
| | - Zi-Yin Cao
- Bryology Laboratory, School of Life Sciences, East China Normal University, Shanghai, China
| | - Lei Shu
- Bryology Laboratory, School of Life Sciences, East China Normal University, Shanghai, China
| | - Rui-Liang Zhu
- Bryology Laboratory, School of Life Sciences, East China Normal University, Shanghai, China
- Tiantong National Station of Forest Ecosystem, Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, East China Normal University, Shanghai, China
- Technology Innovation Center for Land Spatial Eco-restoration in Metropolitan Area, Ministry of Natural Resources, Shanghai, China
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18
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Crichton KA, Anderson K, Charman DJ, Gallego-Sala A. Seasonal climate drivers of peak NDVI in a series of Arctic peatlands. Sci Total Environ 2022; 838:156419. [PMID: 35662594 DOI: 10.1016/j.scitotenv.2022.156419] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Revised: 05/24/2022] [Accepted: 05/30/2022] [Indexed: 06/15/2023]
Abstract
Changes in plant cover and productivity are important in driving Arctic soil carbon dynamics and sequestration, especially in peatlands. Warming trends in the Arctic are known to have resulted in changes in plant productivity, extent and community composition, but more data are still needed to improve understanding of the complex controls and processes involved. Here we assess plant productivity response to climate variability between 1985 and 2020 by comparing peak growing season NDVI (Normalised Difference Vegetation Index data from Landsat 5 and 7), to seasonal-average weather data (temperature, precipitation and snow-melt timing) in nine locations containing peatlands in high- and low-Arctic regions in Europe and Canada. We find that spring (correlation 0.36 for peat dominant and 0.39 for mosaic; MLR coefficient 0.20 for peat, 0.29 for mosaic), summer (0.47, 0.42; 0.18, 0.17) and preceding-autumn (0.35, 0.25; 0.33, 0.27) temperature are linked to peak growing season NDVI at our sites between 1985 and 2020, whilst spring snow melt timing (0.42, 0.45; 0.25, 0.32) is also important, and growing season water availability is likely site-specific. According to regression trees, a warm preceding autumn (September-October-November) is more important than a warm summer (June-July-August) in predicting the highest peak season productivity in the peat-dominated areas. Mechanisms linked to soil processes may explain the importance of previous-Autumn conditions on productivity. We further find that peak productivity increases in these Arctic peatlands are comparable to those in the surrounding non-peatland-dominant vegetation. Increased productivity in and around Arctic peatlands suggests a potential to increased soil carbon sequestration with future warming, but further work is needed to test whether this is evident in observations of recent peat accumulation and extent.
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Affiliation(s)
| | - Karen Anderson
- Department of Geography, University of Exeter, Exeter, UK
| | - Dan J Charman
- Department of Geography, University of Exeter, Exeter, UK
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19
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Piatkowski BT, Carper DL, Carrell AA, Chen IA, Clum A, Daum C, Eloe-fadrosh EA, Gilbert D, Granath G, Huntemann M, Jawdy SS, Klarenberg IJ, Kostka JE, Kyrpides NC, Lawrence TJ, Mukherjee S, Nilsson MB, Palaniappan K, Pelletier DA, Pennacchio C, Reddy TBK, Roux S, Shaw AJ, Warshan D, Živković T, Weston DJ. Draft Metagenome Sequences of the Sphagnum (Peat Moss) Microbiome from Ambient and Warmed Environments across Europe. Microbiol Resour Announc 2022. [PMID: 36069554 PMCID: PMC9584203 DOI: 10.1128/mra.00400-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
We present 49 metagenome assemblies of the microbiome associated with Sphagnum (peat moss) collected from ambient, artificially warmed, and geothermally warmed conditions across Europe. These data will enable further research regarding the impact of climate change on plant-microbe symbiosis, ecology, and ecosystem functioning of northern peatland ecosystems.
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20
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Kulshrestha S, Jibran R, van Klink JW, Zhou Y, Brummell DA, Albert NW, Schwinn KE, Chagné D, Landi M, Bowman JL, Davies KM. Stress, senescence, and specialized metabolites in bryophytes. J Exp Bot 2022; 73:4396-4411. [PMID: 35259256 PMCID: PMC9291361 DOI: 10.1093/jxb/erac085] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Accepted: 03/07/2022] [Indexed: 05/04/2023]
Abstract
Life on land exposes plants to varied abiotic and biotic environmental stresses. These environmental drivers contributed to a large expansion of metabolic capabilities during land plant evolution and species diversification. In this review we summarize knowledge on how the specialized metabolite pathways of bryophytes may contribute to stress tolerance capabilities. Bryophytes are the non-tracheophyte land plant group (comprising the hornworts, liverworts, and mosses) and rapidly diversified following the colonization of land. Mosses and liverworts have as wide a distribution as flowering plants with regard to available environments, able to grow in polar regions through to hot desert landscapes. Yet in contrast to flowering plants, for which the biosynthetic pathways, transcriptional regulation, and compound function of stress tolerance-related metabolite pathways have been extensively characterized, it is only recently that similar data have become available for bryophytes. The bryophyte data are compared with those available for angiosperms, including examining how the differing plant forms of bryophytes and angiosperms may influence specialized metabolite diversity and function. The involvement of stress-induced specialized metabolites in senescence and nutrient response pathways is also discussed.
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Affiliation(s)
- Samarth Kulshrestha
- The New Zealand Institute for Plant and Food Research Limited, Private Bag 11600, Palmerston North 4442, New Zealand
| | - Rubina Jibran
- The New Zealand Institute for Plant and Food Research Limited, Private Bag 92169, Auckland Mail Centre, Auckland 1142, New Zealand
| | - John W van Klink
- The New Zealand Institute for Plant and Food Research Limited, Department of Chemistry, Otago University, Dunedin, New Zealand
| | - Yanfei Zhou
- The New Zealand Institute for Plant and Food Research Limited, Private Bag 11600, Palmerston North 4442, New Zealand
| | - David A Brummell
- The New Zealand Institute for Plant and Food Research Limited, Private Bag 11600, Palmerston North 4442, New Zealand
| | - Nick W Albert
- The New Zealand Institute for Plant and Food Research Limited, Private Bag 11600, Palmerston North 4442, New Zealand
| | - Kathy E Schwinn
- The New Zealand Institute for Plant and Food Research Limited, Private Bag 11600, Palmerston North 4442, New Zealand
| | - David Chagné
- The New Zealand Institute for Plant and Food Research Limited, Private Bag 11600, Palmerston North 4442, New Zealand
| | - Marco Landi
- Department of Agriculture, Food and Environment, University of Pisa, Italy
| | - John L Bowman
- School of Biological Sciences, Monash University, Melbourne, VIC, Australia
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21
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Bao T, Jia G, Xu X. Warming enhances dominance of vascular plants over cryptogams across northern wetlands. Glob Chang Biol 2022; 28:4097-4109. [PMID: 35364612 DOI: 10.1111/gcb.16182] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Revised: 01/13/2022] [Accepted: 03/26/2022] [Indexed: 06/14/2023]
Abstract
Climate warming causes profound effects on structure and function of wetland ecosystem, thus affecting regional and global hydrological cycles and carbon budgets. However, how wetland plants respond to warming is still poorly understood. Here, we synthesized observations from 273 independent sites to explore responses of northern wetland plants to warming. Our results show that warming enhances biomass accumulation for vascular plants including shrubs and graminoids, whereas it reduces biomass accumulation for cryptogams including moss and lichen. This divergent response of vascular plants and cryptogams is particularly pronounced in the high latitudes where permafrost prevails. As warming continues, this divergent response is amplified, however, the reduction in cryptogams is more drastic. Warming leads to declined surface soil moisture and lowered water table, thereby shifting wetlands from a wet system dominated by cryptogams to a drier system with increased cover of vascular plants. Under a high-emission scenario of Shared Socioeconomic Pathways (SSP5), a 4.7-5.1°C mean global temperature rise will cause more than fivefold loss of cryptogams compared with current climate. As cryptogams are largely concentrated at northern high latitudes, where warming will likely be greater than the projected global mean, modification in wetland plant composition and major reduction in cryptogams are expected to occur even much earlier than 2100.
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Affiliation(s)
- Tao Bao
- Key Laboratory of Regional Climate-Environment for Temperate East Asia, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, China
| | - Gensuo Jia
- Key Laboratory of Regional Climate-Environment for Temperate East Asia, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, China
| | - Xiyan Xu
- Key Laboratory of Regional Climate-Environment for Temperate East Asia, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, China
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22
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Antala M, Juszczak R, van der Tol C, Rastogi A. Impact of climate change-induced alterations in peatland vegetation phenology and composition on carbon balance. Sci Total Environ 2022; 827:154294. [PMID: 35247401 DOI: 10.1016/j.scitotenv.2022.154294] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Revised: 02/03/2022] [Accepted: 02/28/2022] [Indexed: 06/14/2023]
Abstract
Global climate is changing faster than humankind has ever experienced. Model-based predictions of future climate are becoming more complex and precise, but they still lack crucial information about the reaction of some important ecosystems, such as peatlands. Peatlands belong to one of the largest carbon stores on the Earth. They are mostly distributed in high latitudes, where the temperature rises faster than in the other parts of the planet. Warmer climate and changes in precipitation patterns cause changes in the composition and phenology of peatland vegetation. Peat mosses are becoming less abundant, vascular plants cover is increasing, and the vegetation season and phenophases of vascular plants start sooner. The alterations in vegetation cause changes in the carbon assimilation and release of greenhouse gases. Therefore, this article reviews the impact of climate change-induced alterations in peatland vegetation phenology and composition on future climate and the uncertainties that need to be addressed for more accurate climate prediction.
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Affiliation(s)
- Michal Antala
- Laboratory of Bioclimatology, Department of Ecology and Environmental Protection, Faculty of Environmental Engineering and Mechanical Engineering, Poznan University of Life Sciences, Piątkowska 94, 60-649 Poznań, Poland
| | - Radoslaw Juszczak
- Laboratory of Bioclimatology, Department of Ecology and Environmental Protection, Faculty of Environmental Engineering and Mechanical Engineering, Poznan University of Life Sciences, Piątkowska 94, 60-649 Poznań, Poland
| | - Christiaan van der Tol
- Faculty of Geo-Information Science and Earth Observation (ITC), University of Twente, 7500 AE Enschede, the Netherlands
| | - Anshu Rastogi
- Laboratory of Bioclimatology, Department of Ecology and Environmental Protection, Faculty of Environmental Engineering and Mechanical Engineering, Poznan University of Life Sciences, Piątkowska 94, 60-649 Poznań, Poland; Faculty of Geo-Information Science and Earth Observation (ITC), University of Twente, 7500 AE Enschede, the Netherlands.
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23
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Carrell AA, Lawrence TJ, Cabugao KGM, Carper DL, Pelletier DA, Lee JH, Jawdy SS, Grimwood J, Schmutz J, Hanson PJ, Shaw AJ, Weston DJ. Habitat-adapted microbial communities mediate Sphagnum peatmoss resilience to warming. New Phytol 2022; 234:2111-2125. [PMID: 35266150 PMCID: PMC9310625 DOI: 10.1111/nph.18072] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Accepted: 02/21/2022] [Indexed: 05/19/2023]
Abstract
Sphagnum peatmosses are fundamental members of peatland ecosystems, where they contribute to the uptake and long-term storage of atmospheric carbon. Warming threatens Sphagnum mosses and is known to alter the composition of their associated microbiome. Here, we use a microbiome transfer approach to test if microbiome thermal origin influences host plant thermotolerance. We leveraged an experimental whole-ecosystem warming study to collect field-grown Sphagnum, mechanically separate the associated microbiome and then transfer onto germ-free laboratory Sphagnum for temperature experiments. Host and microbiome dynamics were assessed with growth analysis, Chla fluorescence imaging, metagenomics, metatranscriptomics and 16S rDNA profiling. Microbiomes originating from warming field conditions imparted enhanced thermotolerance and growth recovery at elevated temperatures. Metagenome and metatranscriptome analyses revealed that warming altered microbial community structure in a manner that induced the plant heat shock response, especially the HSP70 family and jasmonic acid production. The heat shock response was induced even without warming treatment in the laboratory, suggesting that the warm-microbiome isolated from the field provided the host plant with thermal preconditioning. Our results demonstrate that microbes, which respond rapidly to temperature alterations, can play key roles in host plant growth response to rapidly changing environments.
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Affiliation(s)
- Alyssa A. Carrell
- Biosciences DivisionOak Ridge National Laboratory1 Bethel Valley RdOak RidgeTN37831USA
| | - Travis J. Lawrence
- Biosciences DivisionOak Ridge National Laboratory1 Bethel Valley RdOak RidgeTN37831USA
| | - Kristine Grace M. Cabugao
- Bredesen Center for Interdisciplinary Research and Graduate EducationUniversity of Tennessee1502 Cumberland Ave.KnoxvilleTN37996USA
| | - Dana L. Carper
- Biosciences DivisionOak Ridge National Laboratory1 Bethel Valley RdOak RidgeTN37831USA
| | - Dale A. Pelletier
- Biosciences DivisionOak Ridge National Laboratory1 Bethel Valley RdOak RidgeTN37831USA
| | - Jun Hyung Lee
- Biosciences DivisionOak Ridge National Laboratory1 Bethel Valley RdOak RidgeTN37831USA
| | - Sara S. Jawdy
- Biosciences DivisionOak Ridge National Laboratory1 Bethel Valley RdOak RidgeTN37831USA
| | - Jane Grimwood
- HudsonAlpha Institute for Biotechnology601 Genome WayHuntsvilleAL35806USA
- Department of Energy Joint Genome InstituteLawrence Berkeley National Lab1 Cyclotron Rd.BerkeleyCA94720USA
| | - Jeremy Schmutz
- HudsonAlpha Institute for Biotechnology601 Genome WayHuntsvilleAL35806USA
- Department of Energy Joint Genome InstituteLawrence Berkeley National Lab1 Cyclotron Rd.BerkeleyCA94720USA
| | - Paul J. Hanson
- Environmental Sciences DivisionOak Ridge National Laboratory1 Bethel Valley RdOak RidgeTN37831USA
| | | | - David J. Weston
- Biosciences DivisionOak Ridge National Laboratory1 Bethel Valley RdOak RidgeTN37831USA
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24
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Maillard F, Fernandez CW, Mundra S, Heckman KA, Kolka RK, Kauserud H, Kennedy PG. Warming drives a 'hummockification' of microbial communities associated with decomposing mycorrhizal fungal necromass in peatlands. New Phytol 2022; 234:2032-2043. [PMID: 34559896 DOI: 10.1111/nph.17755] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2021] [Accepted: 09/15/2021] [Indexed: 06/13/2023]
Abstract
Dead fungal mycelium (necromass) represents a critical component of soil carbon (C) and nutrient cycles. Assessing how the microbial communities associated with decomposing fungal necromass change as global temperatures rise will help in determining how these belowground organic matter inputs contribute to ecosystem responses. In this study, we characterized the structure of bacterial and fungal communities associated with multiple types of decaying mycorrhizal fungal necromass incubated within mesh bags across a 9°C whole ecosystem temperature enhancement in a boreal peatland. We found major taxonomic and functional shifts in the microbial communities present on decaying mycorrhizal fungal necromass in response to warming. These changes were most pronounced in hollow microsites, which showed convergence towards the necromass-associated microbial communities present in unwarmed hummocks. We also observed a high colonization of ericoid mycorrhizal fungal necromass by fungi from the same genera as the necromass. These results indicate that microbial communities associated with mycorrhizal fungal necromass decomposition are likely to change significantly with future climate warming, which may have strong impacts on soil biogeochemical cycles in peatlands. Additionally, the high enrichment of congeneric fungal decomposers on ericoid mycorrhizal necromass may help to explain the increase in ericoid shrub dominance in warming peatlands.
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Affiliation(s)
- François Maillard
- Department of Plant & Microbial Biology, University of Minnesota, St Paul, MN, 55108, USA
| | - Christopher W Fernandez
- Department of Plant & Microbial Biology, University of Minnesota, St Paul, MN, 55108, USA
- Department of Forestry, Michigan State University, East Lansing, MI, 48824, USA
| | - Sunil Mundra
- Section for Genetics and Evolutionary Biology (EvoGene), Department of Biosciences, University of Oslo, Oslo, NO-0316, Norway
- Department of Biology, College of Science, United Arab Emirates University, Al-Ain, Abu-Dhabi, UAE
| | | | - Randall K Kolka
- USDA Forest Service Northern Research Station, Grand Rapids, MN, 55744, USA
| | - Håvard Kauserud
- Section for Genetics and Evolutionary Biology (EvoGene), Department of Biosciences, University of Oslo, Oslo, NO-0316, Norway
| | - Peter G Kennedy
- Department of Plant & Microbial Biology, University of Minnesota, St Paul, MN, 55108, USA
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25
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Le TB, Wu J, Gong Y. Vascular plants regulate responses of boreal peatland Sphagnum to climate warming and nitrogen addition. Sci Total Environ 2022; 819:152077. [PMID: 34856288 DOI: 10.1016/j.scitotenv.2021.152077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Revised: 11/25/2021] [Accepted: 11/26/2021] [Indexed: 06/13/2023]
Abstract
Boreal peatland Sphagnum may be affected by climate warming and elevated nitrogen availability directly and indirectly via altering vascular plant interaction. Here, we used a field experiment of nitrogen addition, warming, and vascular plant removal to investigate the effects of these factors on Sphagnum in a Canadian blanket boreal peatland. We revealed that significant effects of warming and nitrogen addition on Sphagnum were regulated by vascular plant interaction. The intense competition of vascular plants accelerated an adverse effect of warming on Sphagnum, while facilitation of vascular plants reduced detrimental losses of the Sphagnum due to high dose of nitrogen addition and both warming and the nitrogen addition. These findings indicate the crucial role of vascular plants in regulating the effects of environmental changes on existing Sphagnum in boreal peatlands.
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Affiliation(s)
- Thuong Ba Le
- Environment and Sustainability, School of Science and the Environment, Memorial University of Newfoundland, Corner Brook, NL A2H 5G4, Canada; Graduate Program in Environmental Science, Memorial University of Newfoundland, St. John's, NL, Canada; Vietnam National University of Forestry, Hanoi, Viet Nam
| | - Jianghua Wu
- Environment and Sustainability, School of Science and the Environment, Memorial University of Newfoundland, Corner Brook, NL A2H 5G4, Canada; Graduate Program in Environmental Science, Memorial University of Newfoundland, St. John's, NL, Canada.
| | - Yu Gong
- Environment and Sustainability, School of Science and the Environment, Memorial University of Newfoundland, Corner Brook, NL A2H 5G4, Canada; Graduate Program in Environmental Science, Memorial University of Newfoundland, St. John's, NL, Canada
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26
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Iversen CM, Latimer J, Brice DJ, Childs J, Vander Stel HM, Defrenne CE, Graham J, Griffiths NA, Malhotra A, Norby RJ, Oleheiser KC, Phillips JR, Salmon VG, Sebestyen SD, Yang X, Hanson PJ. Whole-Ecosystem Warming Increases Plant-Available Nitrogen and Phosphorus in an Ombrotrophic Bog. Ecosystems 2022. [DOI: 10.1007/s10021-022-00744-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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27
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Cory AB, Chanton JP, Spencer RGM, Ogles OC, Rich VI, McCalley CK, Wilson RM. Quantifying the inhibitory impact of soluble phenolics on anaerobic carbon mineralization in a thawing permafrost peatland. PLoS One 2022; 17:e0252743. [PMID: 35108267 PMCID: PMC8809605 DOI: 10.1371/journal.pone.0252743] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Accepted: 01/01/2022] [Indexed: 11/24/2022] Open
Abstract
The mechanisms controlling the extraordinarily slow carbon (C) mineralization rates characteristic of Sphagnum-rich peatlands (“bogs”) are not fully understood, despite decades of research on this topic. Soluble phenolic compounds have been invoked as potentially significant contributors to bog peat recalcitrance due to their affinity to slow microbial metabolism and cell growth. Despite this potentially significant role, the effects of soluble phenolic compounds on bog peat C mineralization remain unclear. We analyzed this effect by manipulating the concentration of free soluble phenolics in anaerobic bog and fen peat incubations using water-soluble polyvinylpyrrolidone (“PVP”), a compound that binds with and inactivates phenolics, preventing phenolic-enzyme interactions. CO2 and CH4 production rates (end-products of anaerobic C mineralization) generally correlated positively with PVP concentration following Michaelis-Menten (M.M.) saturation functions. Using M.M. parameters, we estimated that the extent to which phenolics inhibit anaerobic CO2 production was significantly higher in the bog—62 ± 16%—than the fen—14 ± 4%. This difference was found to be more substantial with regards to methane production—wherein phenolic inhibition for the bog was estimated at 54 ± 19%, while the fen demonstrated no apparent inhibition. Consistent with this habitat difference, we observed significantly higher soluble phenolic content in bog vs. fen pore-water. Together, these findings suggest that soluble phenolics could contribute to bogs’ extraordinary recalcitrance and high (relative to other peatland habitats) CO2:CH4 production ratios.
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Affiliation(s)
- Alexandra B. Cory
- Department of Earth, Ocean, and Atmospheric Science, Florida State University, Tallahassee, FL, United States of America
- * E-mail:
| | - Jeffrey P. Chanton
- Department of Earth, Ocean, and Atmospheric Science, Florida State University, Tallahassee, FL, United States of America
| | - Robert G. M. Spencer
- Department of Earth, Ocean, and Atmospheric Science, Florida State University, Tallahassee, FL, United States of America
| | - Olivia C. Ogles
- Department of Earth, Ocean, and Atmospheric Science, Florida State University, Tallahassee, FL, United States of America
| | - Virginia I. Rich
- Department of Microbiology, The Ohio State University, Columbus, OH, United States of America
| | - Carmody K. McCalley
- Thomas H. Gosnell School of Life Sciences, Rochester Institute of Technology, Rochester, NY, United States of America
| | | | | | - Rachel M. Wilson
- Department of Earth, Ocean, and Atmospheric Science, Florida State University, Tallahassee, FL, United States of America
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28
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Kolton M, Weston DJ, Mayali X, Weber PK, Mcfarlane KJ, Pett-ridge J, Somoza MM, Lietard J, Glass JB, Lilleskov EA, Shaw AJ, Tringe S, Hanson PJ, Kostka JE, Martiny JBH. Defining the Sphagnum Core Microbiome across the North American Continent Reveals a Central Role for Diazotrophic Methanotrophs in the Nitrogen and Carbon Cycles of Boreal Peatland Ecosystems. mBio 2022; 13:e03714-21. [DOI: 10.1128/mbio.03714-21] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Peat mosses of the genus Sphagnum are ecosystem engineers that frequently predominate over photosynthetic production in boreal peatlands. Sphagnum spp. host diverse microbial communities capable of nitrogen fixation (diazotrophy) and methane oxidation (methanotrophy), thereby potentially supporting plant growth under severely nutrient-limited conditions. Moreover, diazotrophic methanotrophs represent a possible “missing link” between the carbon and nitrogen cycles, but the functional contributions of the Sphagnum-associated microbiome remain in question. A combination of metagenomics, metatranscriptomics, and dual-isotope incorporation assays was applied to investigate Sphagnum microbiome community composition across the North American continent and provide empirical evidence for diazotrophic methanotrophy in Sphagnum-dominated ecosystems. Remarkably consistent prokaryotic communities were detected in over 250 Sphagnum SSU rRNA libraries from peatlands across the United States (5 states, 17 bog/fen sites, 18 Sphagnum species), with 12 genera of the core microbiome comprising 60% of the relative microbial abundance. Additionally, nitrogenase (nifH) and SSU rRNA gene amplicon analysis revealed that nitrogen-fixing populations made up nearly 15% of the prokaryotic communities, predominated by Nostocales cyanobacteria and Rhizobiales methanotrophs. While cyanobacteria comprised the vast majority (>95%) of diazotrophs detected in amplicon and metagenome analyses, obligate methanotrophs of the genus Methyloferula (order Rhizobiales) accounted for one-quarter of transcribed nifH genes. Furthermore, in dual-isotope tracer experiments, members of the Rhizobiales showed substantial incorporation of 13CH4 and 15N2 isotopes into their rRNA. Our study characterizes the core Sphagnum microbiome across large spatial scales and indicates that diazotrophic methanotrophs, here defined as obligate methanotrophs of the rare biosphere (Methyloferula spp. of the Rhizobiales) that also carry out diazotrophy, play a keystone role in coupling of the carbon and nitrogen cycles in nutrient-poor peatlands.
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29
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Ofiti NOE, Solly EF, Hanson PJ, Malhotra A, Wiesenberg GLB, Schmidt MWI. Warming and elevated CO 2 promote rapid incorporation and degradation of plant-derived organic matter in an ombrotrophic peatland. Glob Chang Biol 2022; 28:883-898. [PMID: 34689380 PMCID: PMC9299048 DOI: 10.1111/gcb.15955] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Accepted: 09/30/2021] [Indexed: 05/19/2023]
Abstract
Rising temperatures have the potential to directly affect carbon cycling in peatlands by enhancing organic matter (OM) decomposition, contributing to the release of CO2 and CH4 to the atmosphere. In turn, increasing atmospheric CO2 concentration may stimulate photosynthesis, potentially increasing plant litter inputs belowground and transferring carbon from the atmosphere into terrestrial ecosystems. Key questions remain about the magnitude and rate of these interacting and opposing environmental change drivers. Here, we assess the incorporation and degradation of plant- and microbe-derived OM in an ombrotrophic peatland after 4 years of whole-ecosystem warming (+0, +2.25, +4.5, +6.75 and +9°C) and two years of elevated CO2 manipulation (500 ppm above ambient). We show that OM molecular composition was substantially altered in the aerobic acrotelm, highlighting the sensitivity of acrotelm carbon to rising temperatures and atmospheric CO2 concentration. While warming accelerated OM decomposition under ambient CO2 , new carbon incorporation into peat increased in warming × elevated CO2 treatments for both plant- and microbe-derived OM. Using the isotopic signature of the applied CO2 enrichment as a label for recently photosynthesized OM, our data demonstrate that new plant inputs have been rapidly incorporated into peat carbon. Our results suggest that under current hydrological conditions, rising temperatures and atmospheric CO2 levels will likely offset each other in boreal peatlands.
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Affiliation(s)
| | - Emily F. Solly
- Group for Sustainable AgroecosystemsDepartment of Environmental Systems ScienceETH ZurichZurichSwitzerland
| | - Paul J. Hanson
- Environmental Sciences Division and Climate Change Science InstituteOak Ridge National LaboratoryOak RidgeTennesseeUSA
| | - Avni Malhotra
- Department of GeographyUniversity of ZurichZurichSwitzerland
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30
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Andrews LO, Rowson JG, Caporn SJM, Dise NB, Barton E, Garrett E, Gehrels WR, Gehrels M, Kay M, Payne RJ. Plant community responses to experimental climate manipulation in a Welsh ombrotrophic peatland and their palaeoenvironmental context. Glob Chang Biol 2022; 28:1596-1617. [PMID: 34800308 DOI: 10.1111/gcb.16003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Accepted: 10/26/2021] [Indexed: 06/13/2023]
Abstract
We test whether vegetation community composition from a 10-year climate manipulation experiment on a Welsh peat bog resembles vegetation communities during periods of climate change inferred from a peat core. Experimentally warmed and combined warmed and droughted treatments drove significant increases in ericaceous shrubs but Sphagnum was unaffected. Similarly, Calluna vulgaris seeds increase during inferred warmer periods in the palaeoecological record. Experimental short-term episodic drought (four 4-week drought treatments) did not affect vegetation. Plant community composition has undergone several abrupt changes throughout the past c. 1500 years, often in response to human disturbance. Only slight changes occurred during the Medieval Climate Anomaly (c. 950-1250 Common Era [CE]) in vegetation and hydrology, while abrupt changes occurred during the Little Ice Age (c. 1300-1850 CE) when water tables were highest, suggesting that these shifts were driven by changes in water table, modulated by climate. A period of water table drawdown c. 1800, synchronous with historical records of increased drainage, corresponds with the development of the present-day vegetation community. Modern analogues for fossil material, characterized by abundant Rhynchospora alba and Sphagnum pulchrum, are more common after this event. Vegetation changes due to climate inferred from the palaeo record differ from those observed in the experiments, possibly relating to differences in the importance of drivers of vegetation change over varying timescales. Whereas temperature is frequently identified as the dominant driver of plant community change in experiments, sustained changes in water table appear to be more important in the long-term record. We find evidence that recent climate change and other anthropogenic stressors (e.g. drainage, heavy metal and nitrogen pollution) may promote the development of novel plant communities without analogues in the fossil record. These communities may be poorer at sequestering carbon and may respond differently to future climate change.
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Affiliation(s)
- Luke O Andrews
- Department of Environment and Geography, University of York, York, UK
| | - James G Rowson
- Department of Geography and Geology, Edge Hill University, Lancashire, UK
| | - Simon J M Caporn
- Department of Natural Sciences, Manchester Metropolitan University, Manchester, UK
| | | | - Eleanor Barton
- Department of Environment and Geography, University of York, York, UK
| | - Ed Garrett
- Department of Environment and Geography, University of York, York, UK
| | - W Roland Gehrels
- Department of Environment and Geography, University of York, York, UK
| | - Maria Gehrels
- Department of Environment and Geography, University of York, York, UK
| | - Martin Kay
- Geography, School of Environment, Education and Development, The University of Manchester, Manchester, UK
| | - Richard J Payne
- Department of Environment and Geography, University of York, York, UK
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31
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Sun B, Jiang M, Han G, Zhang L, Zhou J, Bian C, Du Y, Yan L, Xia J. Experimental warming reduces ecosystem resistance and resilience to severe flooding in a wetland. Sci Adv 2022; 8:eabl9526. [PMID: 35080980 PMCID: PMC8791607 DOI: 10.1126/sciadv.abl9526] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Climate warming and extreme hydrological events are threatening the sustainability of wetlands across the globe. However, whether climate warming will amplify or diminish the impact of extreme flooding on wetland ecosystems is unknown. Here, we show that climate warming significantly reduced wetland resistance and resilience to a severe flooding event via a 6-year warming experiment. We first found that warming rapidly altered plant community structure by increasing the dominance of low-canopy species. Then, we showed that warming reduced the resistance and resilience of vegetation productivity to a 72-cm flooding event. Last, we detected slower postflooding carbon processes, such as gross ecosystem productivity, soil respiration, and soil methane emission, under the warming treatment. Our results demonstrate how severe flooding can destabilize wetland vegetation structure and ecosystem function under climate warming. These findings indicate an enhanced footprint of extreme hydrological events in wetland ecosystems in a warmer climate.
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Affiliation(s)
- Baoyu Sun
- State Key Laboratory of Estuarine and Coastal Research, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200000, China
- Key Laboratory of Coastal Zone Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264000, China
| | - Ming Jiang
- State Key Laboratory of Estuarine and Coastal Research, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200000, China
| | - Guangxuan Han
- Key Laboratory of Coastal Zone Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264000, China
- University of Chinese Academy of Sciences, Beijing 100000, China
| | - Liwen Zhang
- Key Laboratory of Coastal Zone Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264000, China
- University of Chinese Academy of Sciences, Beijing 100000, China
| | - Jian Zhou
- State Key Laboratory of Estuarine and Coastal Research, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200000, China
- Research Center for Global Change and Complex Ecosystems, East China Normal University, Shanghai 200000, China
| | - Chenyu Bian
- State Key Laboratory of Estuarine and Coastal Research, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200000, China
- Research Center for Global Change and Complex Ecosystems, East China Normal University, Shanghai 200000, China
| | - Ying Du
- State Key Laboratory of Estuarine and Coastal Research, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200000, China
- Research Center for Global Change and Complex Ecosystems, East China Normal University, Shanghai 200000, China
| | - Liming Yan
- State Key Laboratory of Estuarine and Coastal Research, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200000, China
- Research Center for Global Change and Complex Ecosystems, East China Normal University, Shanghai 200000, China
| | - Jianyang Xia
- State Key Laboratory of Estuarine and Coastal Research, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200000, China
- Research Center for Global Change and Complex Ecosystems, East China Normal University, Shanghai 200000, China
- Corresponding author.
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32
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AminiTabrizi R, Dontsova K, Graf Grachet N, Tfaily MM. Elevated temperatures drive abiotic and biotic degradation of organic matter in a peat bog under oxic conditions. Sci Total Environ 2022; 804:150045. [PMID: 34798718 DOI: 10.1016/j.scitotenv.2021.150045] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2021] [Revised: 08/26/2021] [Accepted: 08/26/2021] [Indexed: 06/13/2023]
Abstract
Understanding the effects of elevated temperatures on soil organic matter (SOM) decomposition pathways in northern peatlands is central to predicting their fate under future warming. Peatlands role as carbon (C) sink is dependent on both anoxic conditions and low temperatures that limit SOM decomposition. Previous studies have shown that elevated temperatures due to climate change can disrupt peatland's C balance by enhancing SOM decomposition and increasing CO2 emissions. However, little is known about how SOM decomposition pathways change at higher temperatures. Here, we used an integrated research approach to investigate the mechanisms behind enhanced CO2 emissions and SOM decomposition under elevated temperatures of surface peat soil collected from a raised and Sphagnum dominated mid-continental bog (S1 bog) peatland at the Marcel Experimental Forest in Minnesota, USA, incubated under oxic conditions at three different temperatures (4, 21, and 35 °C). Our results indicated that elevated temperatures could destabilize peatland's C pool via a combination of abiotic and biotic processes. In particular, temperature-driven changes in redox conditions can lead to abiotic destabilization of Fe-organic matter (phenol) complexes, previously an underestimated decomposition pathway in peatlands, leading to increased CO2 production and accumulation of polyphenol-like compounds that could further inhibit extracellular enzyme activities and/or fuel the microbial communities with labile compounds. Further, increased temperatures can alter strategies of microbial communities for nutrient acquisition via changes in the activities of extracellular enzymes by priming SOM decomposition, leading to enhanced CO2 emission from peatlands. Therefore, coupled biotic and abiotic processes need to be incorporated into process-based climate models to predict the fate of SOM under elevated temperatures and to project the likely impacts of environmental change on northern peatlands and CO2 emissions.
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Affiliation(s)
- Roya AminiTabrizi
- Department of Environmental Science, The University of Arizona, Tucson, AZ 85721, USA
| | - Katerina Dontsova
- Department of Environmental Science, The University of Arizona, Tucson, AZ 85721, USA
| | - Nathalia Graf Grachet
- Department of Environmental Science, The University of Arizona, Tucson, AZ 85721, USA
| | - Malak M Tfaily
- Department of Environmental Science, The University of Arizona, Tucson, AZ 85721, USA; Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, WA 99354, USA.
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ter Horst AM, Santos-Medellín C, Sorensen JW, Zinke LA, Wilson RM, Johnston ER, Trubl G, Pett-Ridge J, Blazewicz SJ, Hanson PJ, Chanton JP, Schadt CW, Kostka JE, Emerson JB. Minnesota peat viromes reveal terrestrial and aquatic niche partitioning for local and global viral populations. Microbiome 2021; 9:233. [PMID: 34836550 PMCID: PMC8626947 DOI: 10.1186/s40168-021-01156-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Accepted: 09/02/2021] [Indexed: 05/31/2023]
Abstract
BACKGROUND Peatlands are expected to experience sustained yet fluctuating higher temperatures due to climate change, leading to increased microbial activity and greenhouse gas emissions. Despite mounting evidence for viral contributions to these processes in peatlands underlain with permafrost, little is known about viruses in other peatlands. More generally, soil viral biogeography and its potential drivers are poorly understood at both local and global scales. Here, 87 metagenomes and five viral size-fraction metagenomes (viromes) from a boreal peatland in northern Minnesota (the SPRUCE whole-ecosystem warming experiment and surrounding bog) were analyzed for dsDNA viral community ecological patterns, and the recovered viral populations (vOTUs) were compared with our curated PIGEON database of 266,125 vOTUs from diverse ecosystems. RESULTS Within the SPRUCE experiment, viral community composition was significantly correlated with peat depth, water content, and carbon chemistry, including CH4 and CO2 concentrations, but not with temperature during the first 2 years of warming treatments. Peat vOTUs with aquatic-like signatures (shared predicted protein content with marine and/or freshwater vOTUs) were significantly enriched in more waterlogged surface peat depths. Predicted host ranges for SPRUCE vOTUs were relatively narrow, generally within a single bacterial genus. Of the 4326 SPRUCE vOTUs, 164 were previously detected in other soils, mostly peatlands. None of the previously identified 202,371 marine and freshwater vOTUs in our PIGEON database were detected in SPRUCE peat, but 0.4% of 80,714 viral clusters (VCs, grouped by predicted protein content) were shared between soil and aquatic environments. On a per-sample basis, vOTU recovery was 32 times higher from viromes compared with total metagenomes. CONCLUSIONS Results suggest strong viral "species" boundaries between terrestrial and aquatic ecosystems and to some extent between peat and other soils, with differences less pronounced at higher taxonomic levels. The significant enrichment of aquatic-like vOTUs in more waterlogged peat suggests that viruses may also exhibit niche partitioning on more local scales. These patterns are presumably driven in part by host ecology, consistent with the predicted narrow host ranges. Although more samples and increased sequencing depth improved vOTU recovery from total metagenomes, the substantially higher per-sample vOTU recovery after viral particle enrichment highlights the utility of soil viromics. Video abstract The importance of Minnesota peat viromes in revealing terrestrial and aquatic niche partitioning for viral populations.
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Affiliation(s)
| | | | - Jackson W. Sorensen
- Department of Plant Pathology, University of California, Davis, Davis, CA USA
| | - Laura A. Zinke
- Department of Plant Pathology, University of California, Davis, Davis, CA USA
| | - Rachel M. Wilson
- Department of Earth, Ocean, and Atmospheric Science, Florida State University, Tallahassee, FL USA
| | - Eric R. Johnston
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN USA
| | - Gareth Trubl
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, CA USA
| | - Jennifer Pett-Ridge
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, CA USA
| | - Steven J. Blazewicz
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, CA USA
| | - Paul J. Hanson
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN USA
| | - Jeffrey P. Chanton
- Department of Earth, Ocean, and Atmospheric Science, Florida State University, Tallahassee, FL USA
| | | | - Joel E. Kostka
- Schools of Biology and Earth & Atmospheric Sciences, Georgia Institute of Technology, Atlanta, GA USA
- Center for Microbial Dynamics and Infection, Georgia Institute of Technology, Atlanta, GA 30332 USA
| | - Joanne B. Emerson
- Department of Plant Pathology, University of California, Davis, Davis, CA USA
- Genome Center, University of California, Davis, Davis, CA USA
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Shelley SJ, Brice DJ, Iversen CM, Kolka RK, Sebestyen SD, Griffiths NA. Deciphering the shifting role of intrinsic and extrinsic drivers on moss decomposition in peatlands over a 5‐year period. OIKOS 2021. [DOI: 10.1111/oik.08584] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Affiliation(s)
- Sarah J. Shelley
- Oak Ridge Associated Univ. Oak Ridge TN USA
- Univ. of Tennessee Knoxville TN USA
- Climate Change Science Inst. and Environmental Sciences Division, Oak Ridge National Laboratory Oak Ridge TN USA
| | - Deanne J. Brice
- Climate Change Science Inst. and Environmental Sciences Division, Oak Ridge National Laboratory Oak Ridge TN USA
| | - Colleen M. Iversen
- Climate Change Science Inst. and Environmental Sciences Division, Oak Ridge National Laboratory Oak Ridge TN USA
| | - Randy K. Kolka
- Northern Research Station, USDA Forest Service Grand Rapids MN USA
| | | | - Natalie A. Griffiths
- Climate Change Science Inst. and Environmental Sciences Division, Oak Ridge National Laboratory Oak Ridge TN USA
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Zhou Y, Huang Y, Peng X, Xu J, Hu Y. Sphagnum response to nitrogen deposition and nitrogen critical load: A meta-analysis. Glob Ecol Conserv 2021. [DOI: 10.1016/j.gecco.2021.e01791] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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Wilson RM, Tfaily MM, Kolton M, Johnston ER, Petro C, Zalman CA, Hanson PJ, Heyman HM, Kyle JE, Hoyt DW, Eder EK, Purvine SO, Kolka RK, Sebestyen SD, Griffiths NA, Schadt CW, Keller JK, Bridgham SD, Chanton JP, Kostka JE. Soil metabolome response to whole-ecosystem warming at the Spruce and Peatland Responses under Changing Environments experiment. Proc Natl Acad Sci U S A 2021; 118:e2004192118. [PMID: 34161254 DOI: 10.1073/pnas.2004192118] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
In this study, a suite of complementary environmental geochemical analyses, including NMR and gas chromatography-mass spectrometry (GC-MS) analyses of central metabolites, Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS) of secondary metabolites, and lipidomics, was used to investigate the influence of organic matter (OM) quality on the heterotrophic microbial mechanisms controlling peatland CO2, CH4, and CO2:CH4 porewater production ratios in response to climate warming. Our investigations leverage the Spruce and Peatland Responses under Changing Environments (SPRUCE) experiment, where air and peat warming were combined in a whole-ecosystem warming treatment. We hypothesized that warming would enhance the production of plant-derived metabolites, resulting in increased labile OM inputs to the surface peat, thereby enhancing microbial activity and greenhouse gas production. Because shallow peat is most susceptible to enhanced warming, increases in labile OM inputs to the surface, in particular, are likely to result in significant changes to CO2 and CH4 dynamics and methanogenic pathways. In support of this hypothesis, significant correlations were observed between metabolites and temperature consistent with increased availability of labile substrates, which may stimulate more rapid turnover of microbial proteins. An increase in the abundance of methanogenic genes in response to the increase in the abundance of labile substrates was accompanied by a shift toward acetoclastic and methylotrophic methanogenesis. Our results suggest that as peatland vegetation trends toward increasing vascular plant cover with warming, we can expect a concomitant shift toward increasingly methanogenic conditions and amplified climate-peatland feedbacks.
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Kolari THM, Korpelainen P, Kumpula T, Tahvanainen T. Accelerated vegetation succession but no hydrological change in a boreal fen during 20 years of recent climate change. Ecol Evol 2021; 11:7602-7621. [PMID: 34188838 PMCID: PMC8216969 DOI: 10.1002/ece3.7592] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Revised: 03/26/2021] [Accepted: 04/01/2021] [Indexed: 11/17/2022] Open
Abstract
Northern mires (fens and bogs) have significant climate feedbacks and contribute to biodiversity, providing habitats to specialized biota. Many studies have found drying and degradation of bogs in response to climate change, while northern fens have received less attention. Rich fens are particularly important to biodiversity, but subject to global climate change, fen ecosystems may change via direct response of vegetation or indirectly by hydrological changes. With repeated sampling over the past 20 years, we aim to reveal trends in hydrology and vegetation in a pristine boreal fen with gradient from rich to poor fen and bog vegetation. We resampled 203 semi-permanent plots and compared water-table depth (WTD), pH, concentrations of mineral elements, and dissolved organic carbon (DOC), plant species occurrences, community structure, and vegetation types between 1998 and 2018. In the study area, the annual mean temperature rose by 1.0°C and precipitation by 46 mm, in 20-year periods prior to sampling occasions. We found that wet fen vegetation decreased, while bog and poor fen vegetation increased significantly. This reflected a trend of increasing abundance of common, generalist hummock species at the expense of fen specialist species. Changes were the most pronounced in high pH plots, where Sphagnum mosses had significantly increased in plot frequency, cover, and species richness. Changes of water chemistry were mainly insignificant in concentration levels and spatial patterns. Although indications toward drier conditions were found in vegetation, WTD had not consistently increased, instead, our results revealed complex dynamics of WTD as depending on vegetation changes. Overall, we found significant trend in vegetation, conforming to common succession pattern from rich to poor fen and bog vegetation. Our results suggest that responses intrinsic to vegetation, such as increased productivity or altered species interactions, may be more significant than indirect effects via local hydrology to the ecosystem response to climate warming.
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Affiliation(s)
- Tiina H. M. Kolari
- Department of Environmental and Biological SciencesUniversity of Eastern FinlandJoensuuFinland
| | - Pasi Korpelainen
- Department of Geographical and Historical StudiesUniversity of Eastern FinlandJoensuuFinland
| | - Timo Kumpula
- Department of Geographical and Historical StudiesUniversity of Eastern FinlandJoensuuFinland
| | - Teemu Tahvanainen
- Department of Environmental and Biological SciencesUniversity of Eastern FinlandJoensuuFinland
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Warren JM, Jensen AM, Ward EJ, Guha A, Childs J, Wullschleger SD, Hanson PJ. Divergent species-specific impacts of whole ecosystem warming and elevated CO 2 on vegetation water relations in an ombrotrophic peatland. Glob Chang Biol 2021; 27:1820-1835. [PMID: 33528056 DOI: 10.1111/gcb.15543] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Revised: 01/08/2021] [Accepted: 01/11/2021] [Indexed: 06/12/2023]
Abstract
Boreal peatland forests have relatively low species diversity and thus impacts of climate change on one or more dominant species could shift ecosystem function. Despite abundant soil water availability, shallowly rooted vascular plants within peatlands may not be able to meet foliar demand for water under drought or heat events that increase vapor pressure deficits while reducing near surface water availability, although concurrent increases in atmospheric CO2 could buffer resultant hydraulic stress. We assessed plant water relations of co-occurring shrub (primarily Rhododendron groenlandicum and Chamaedaphne calyculata) and tree (Picea mariana and Larix laricina) species prior to, and in response to whole ecosystem warming (0 to +9°C) and elevated CO2 using 12.8-m diameter open-top enclosures installed within an ombrotrophic bog. Water relations (water potential [Ψ], turgor loss point, foliar and root hydraulic conductivity) were assessed prior to treatment initiation, then Ψ and peak sap flow (trees only) assessed after 1 or 2 years of treatments. Under the higher temperature treatments, L. laricina Ψ exceeded its turgor loss point, increased its peak sap flow, and was not able to recover Ψ overnight. In contrast, P. mariana operated below its turgor loss point and maintained constant Ψ and sap flow across warming treatments. Similarly, C. calyculata Ψ stress increased with temperature while R. groenlandicum Ψ remained at pretreatment levels. The more anisohydric behavior of L. laricina and C. calyculata may provide greater net C uptake with warming, while the more conservative P. mariana and R. groenlandicum maintained greater hydraulic safety. These latter species also responded to elevated CO2 by reduced Ψ stress, which may also help limit hydraulic failure during periods of extreme drought or heat in the future. Along with Sphagnum moss, the species-specific responses of peatland vascular communities to drier or hotter conditions will shape boreal peatland composition and function in the future.
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Affiliation(s)
- Jeffrey M Warren
- Environmental Sciences Division and Climate Change Science Institute, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - Anna M Jensen
- Department of Forestry and Wood Technology, Linnaeus University, Växjö, Sweden
| | - Eric J Ward
- U.S. Geological Survey, Wetland and Aquatic Research Center, Lafayette, LA, USA
| | - Anirban Guha
- Environmental Sciences Division and Climate Change Science Institute, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - Joanne Childs
- Environmental Sciences Division and Climate Change Science Institute, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - Stan D Wullschleger
- Environmental Sciences Division and Climate Change Science Institute, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - Paul J Hanson
- Environmental Sciences Division and Climate Change Science Institute, Oak Ridge National Laboratory, Oak Ridge, TN, USA
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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
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40
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Heck MA, Lüth VM, van Gessel N, Krebs M, Kohl M, Prager A, Joosten H, Decker EL, Reski R. Axenic in vitro cultivation of 19 peat moss (Sphagnum L.) species as a resource for basic biology, biotechnology, and paludiculture. New Phytol 2021; 229:861-876. [PMID: 32910470 DOI: 10.1111/nph.16922] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Accepted: 08/27/2020] [Indexed: 05/07/2023]
Abstract
Sphagnum farming can substitute peat with renewable biomass and thus help mitigate climate change. Large volumes of the required founder material can only be supplied sustainably by axenic cultivation in bioreactors. We established axenic in vitro cultures from sporophytes of 19 Sphagnum species collected in Austria, Germany, Latvia, the Netherlands, Russia, and Sweden: S. angustifolium, S. balticum, S. capillifolium, S. centrale, S. compactum, S. cuspidatum, S. fallax, S. fimbriatum, S. fuscum, S. lindbergii, S. medium/divinum, S. palustre, S. papillosum, S. rubellum, S. russowii, S. squarrosum, S. subnitens, S. subfulvum and S. warnstorfii. These species cover five of the six European Sphagnum subgenera; namely, Acutifolia, Cuspidata, Rigida, Sphagnum and Squarrosa. Their growth was measured in suspension cultures, whereas their ploidy was determined by flow cytometry and compared with the genome size of Physcomitrella patens. We identified haploid and diploid Sphagnum species, found that their cells are predominantly arrested in the G1 phase of the cell cycle, and did not find a correlation between plant productivity and ploidy. DNA barcoding was achieved by sequencing introns of the BRK1 genes. With this collection, high-quality founder material for diverse large-scale applications, but also for basic Sphagnum research, is available from the International Moss Stock Center.
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Affiliation(s)
- Melanie A Heck
- Plant Biotechnology, Faculty of Biology, University of Freiburg, Freiburg, 79104, Germany
| | - Volker M Lüth
- Plant Biotechnology, Faculty of Biology, University of Freiburg, Freiburg, 79104, Germany
| | - Nico van Gessel
- Plant Biotechnology, Faculty of Biology, University of Freiburg, Freiburg, 79104, Germany
| | - Matthias Krebs
- Peatland Studies and Palaeoecology, Institute of Botany and Landscape Ecology, University of Greifswald, Greifswald, 17487, Germany
- Greifswald Mire Centre, Greifswald, 17489, Germany
| | - Mira Kohl
- Peatland Studies and Palaeoecology, Institute of Botany and Landscape Ecology, University of Greifswald, Greifswald, 17487, Germany
- Greifswald Mire Centre, Greifswald, 17489, Germany
| | - Anja Prager
- Peatland Studies and Palaeoecology, Institute of Botany and Landscape Ecology, University of Greifswald, Greifswald, 17487, Germany
- Greifswald Mire Centre, Greifswald, 17489, Germany
| | - Hans Joosten
- Peatland Studies and Palaeoecology, Institute of Botany and Landscape Ecology, University of Greifswald, Greifswald, 17487, Germany
- Greifswald Mire Centre, Greifswald, 17489, Germany
| | - Eva L Decker
- Plant Biotechnology, Faculty of Biology, University of Freiburg, Freiburg, 79104, Germany
| | - Ralf Reski
- Plant Biotechnology, Faculty of Biology, University of Freiburg, Freiburg, 79104, Germany
- CIBSS - Centre for Integrative Biological Signalling Studies, University of Freiburg, Freiburg, 79104, Germany
- Cluster of Excellence livMatS @ FIT - Freiburg Center for Interactive Materials and Bioinspired Technologies, University of Freiburg, Freiburg, 79110, Germany
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Arroyo-esquivel J, Hastings A. Spatial Dynamics and Spread of Ecosystem Engineers: Two Patch Analysis. Bull Math Biol 2020; 82. [DOI: 10.1007/s11538-020-00833-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Accepted: 11/02/2020] [Indexed: 10/22/2022]
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Malhotra A, Brice DJ, Childs J, Graham JD, Hobbie EA, Vander Stel H, Feron SC, Hanson PJ, Iversen CM. Peatland warming strongly increases fine-root growth. Proc Natl Acad Sci U S A 2020; 117:17627-17634. [PMID: 32661144 PMCID: PMC7395547 DOI: 10.1073/pnas.2003361117] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Belowground climate change responses remain a key unknown in the Earth system. Plant fine-root response is especially important to understand because fine roots respond quickly to environmental change, are responsible for nutrient and water uptake, and influence carbon cycling. However, fine-root responses to climate change are poorly constrained, especially in northern peatlands, which contain up to two-thirds of the world's soil carbon. We present fine-root responses to warming between +2 °C and 9 °C above ambient conditions in a whole-ecosystem peatland experiment. Warming strongly increased fine-root growth by over an order of magnitude in the warmest treatment, with stronger responses in shrubs than in trees or graminoids. In the first year of treatment, the control (+0 °C) shrub fine-root growth of 0.9 km m-2 y-1 increased linearly by 1.2 km m-2 y-1 (130%) for every degree increase in soil temperature. An extended belowground growing season accounted for 20% of this dramatic increase. In the second growing season of treatment, the shrub warming response rate increased to 2.54 km m-2 °C-1 Soil moisture was negatively correlated with fine-root growth, highlighting that drying of these typically water-saturated ecosystems can fuel a surprising burst in shrub belowground productivity, one possible mechanism explaining the "shrubification" of northern peatlands in response to global change. This previously unrecognized mechanism sheds light on how peatland fine-root response to warming and drying could be strong and rapid, with consequences for the belowground growing season duration, microtopography, vegetation composition, and ultimately, carbon function of these globally relevant carbon sinks.
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Affiliation(s)
- Avni Malhotra
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37830;
- Climate Change Science Institute, Oak Ridge National Laboratory, Oak Ridge, TN 37830
| | - Deanne J Brice
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37830
- Climate Change Science Institute, Oak Ridge National Laboratory, Oak Ridge, TN 37830
| | - Joanne Childs
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37830
- Climate Change Science Institute, Oak Ridge National Laboratory, Oak Ridge, TN 37830
| | - Jake D Graham
- Department of Geosciences, Boise State University, Boise, ID 83725
| | - Erik A Hobbie
- Earth Systems Research Center, University of New Hampshire, Durham, NH 03824
| | - Holly Vander Stel
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37830
- Climate Change Science Institute, Oak Ridge National Laboratory, Oak Ridge, TN 37830
- Kellogg Biological Station, Michigan State University, Hickory Corners, MI 49060
| | - Sarah C Feron
- Department of Physics, Universidad de Santiago de Chile, Santiago, 9170022, Chile
- School of Earth, Energy and Environmental Sciences, Department of Earth System Science, Stanford University, Stanford, CA 94305
| | - Paul J Hanson
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37830
- Climate Change Science Institute, Oak Ridge National Laboratory, Oak Ridge, TN 37830
| | - Colleen M Iversen
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37830
- Climate Change Science Institute, Oak Ridge National Laboratory, Oak Ridge, TN 37830
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Rastogi A, Antala M, Gąbka M, Rosadziński S, Stróżecki M, Brestic M, Juszczak R. Impact of warming and reduced precipitation on morphology and chlorophyll concentration in peat mosses (Sphagnum angustifolium and S. fallax). Sci Rep 2020; 10:8592. [PMID: 32451474 PMCID: PMC7248058 DOI: 10.1038/s41598-020-65032-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Accepted: 04/15/2020] [Indexed: 12/02/2022] Open
Abstract
Peatlands are one of the most important ecosystems due to their biodiversity and abundant organic compounds; therefore, it is important to observe how different plant species in peatlands react to changing environmental conditions. Sphagnum spp. are the main component of peatlands and are considered as the creator of conditions favorable for carbon storage in the form of peat. Sphagnum angustifolium and Sphagnum fallax are taxonomically very close species. To examine their adaptability to climate change, we studied the morphology and pigment content of these two species from environmental manipulation sites in Poland, where the environment was continuously manipulated for temperature and precipitation. The warming of peat was induced by using infrared heaters, whereas total precipitation was reduced by a curtain that cuts the nighttime precipitation. Morphology of S. angustifolium stayed under climate manipulation relatively stable. However, the main morphological parameters of S. fallax were significantly affected by precipitation reduction. Thus, this study indicates S. angustifolium is better adapted in comparison to S. fallax for drier and warmer conditions.
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Affiliation(s)
- Anshu Rastogi
- Laboratory of Bioclimatology, Department of Ecology and Environmental Protection, Poznan University of Life Sciences, Piątkowska 94, 60-649, Poznan, Poland.
| | - Michal Antala
- Laboratory of Bioclimatology, Department of Ecology and Environmental Protection, Poznan University of Life Sciences, Piątkowska 94, 60-649, Poznan, Poland
- Department of Plant Physiology, Slovak University of Agriculture, A. Hlinku 2, 94976, Nitra, Slovak Republic
| | - Maciej Gąbka
- Department of Hydrobiology, Adam Mickiewicz University in Poznań, Uniwersytetu Poznańskiego 6, 61-614, Poznań, Poland.
| | - Stanisław Rosadziński
- Adam Mickiewicz University in Poznań, Uniwersytetu Poznańskiego 6, 61-614, Poznań, Poland
| | - Marcin Stróżecki
- Laboratory of Bioclimatology, Department of Ecology and Environmental Protection, Poznan University of Life Sciences, Piątkowska 94, 60-649, Poznan, Poland
| | - Marian Brestic
- Department of Plant Physiology, Slovak University of Agriculture, A. Hlinku 2, 94976, Nitra, Slovak Republic
- Department of Botany and Plant Physiology, Faculty of Agrobiology, Food and Natural Resources Czech University of Life Sciences, 16500 Prague, Czech Republic
| | - Radosław Juszczak
- Laboratory of Bioclimatology, Department of Ecology and Environmental Protection, Poznan University of Life Sciences, Piątkowska 94, 60-649, Poznan, Poland
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Kluber LA, Johnston ER, Allen SA, Hendershot JN, Hanson PJ, Schadt CW. Constraints on microbial communities, decomposition and methane production in deep peat deposits. PLoS One 2020; 15:e0223744. [PMID: 32027653 PMCID: PMC7004313 DOI: 10.1371/journal.pone.0223744] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Accepted: 01/20/2020] [Indexed: 11/19/2022] Open
Abstract
Peatlands play outsized roles in the global carbon cycle. Despite occupying a rather small fraction of the terrestrial biosphere (~3%), these ecosystems account for roughly one third of the global soil carbon pool. This carbon is largely comprised of undecomposed deposits of plant material (peat) that may be meters thick. The fate of this deep carbon stockpile with ongoing and future climate change is thus of great interest and has large potential to induce positive feedback to climate warming. Recent in situ warming of an ombrotrophic peatland indicated that the deep peat microbial communities and decomposition rates were resistant to elevated temperatures. In this experiment, we sought to understand how nutrient and pH limitations may interact with temperature to limit microbial activity and community composition. Anaerobic microcosms of peat collected from 1.5 to 2 meters in depth were incubated at 6°C and 15°C with elevated pH, nitrogen (NH4Cl), and/or phosphorus (KH2PO4) in a full factorial design. The production of CO2 and CH4 was significantly greater in microcosms incubated at 15°C, although the structure of the microbial community did not differ between the two temperatures. Increasing the pH from ~3.5 to ~5.5 altered microbial community structure, however increases in CH4 production were non-significant. Contrary to expectations, N and P additions did not increase CO2 and CH4 production, indicating that nutrient availability was not a primary constraint in microbial decomposition of deep peat. Our findings indicate that temperature is a key factor limiting the decomposition of deep peat, however other factors such as the availability of O2 or alternative electron donors and high concentrations of phenolic compounds, may also exert constraints. Continued experimental peat warming studies will be necessary to assess if the deep peat carbon bank is susceptible to increased temperatures over the longer time scales.
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Affiliation(s)
- Laurel A. Kluber
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, United States of America
- Climate Change Sciences Institute, Oak Ridge National Laboratory, Oak Ridge, TN, United States of America
| | - Eric R. Johnston
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, United States of America
- Climate Change Sciences Institute, Oak Ridge National Laboratory, Oak Ridge, TN, United States of America
| | - Samantha A. Allen
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, United States of America
- Climate Change Sciences Institute, Oak Ridge National Laboratory, Oak Ridge, TN, United States of America
| | - J. Nicholas Hendershot
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, United States of America
- Climate Change Sciences Institute, Oak Ridge National Laboratory, Oak Ridge, TN, United States of America
| | - Paul J. Hanson
- Climate Change Sciences Institute, Oak Ridge National Laboratory, Oak Ridge, TN, United States of America
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, United States of America
| | - Christopher W. Schadt
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, United States of America
- Climate Change Sciences Institute, Oak Ridge National Laboratory, Oak Ridge, TN, United States of America
- Department of Microbiology, University of Tennessee, Knoxville, TN, United States of America
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