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Schuur EAG, Hicks Pries C, Mauritz M, Pegoraro E, Rodenhizer H, See C, Ebert C. Ecosystem and soil respiration radiocarbon detects old carbon release as a fingerprint of warming and permafrost destabilization with climate change. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2023; 381:20220201. [PMID: 37807688 PMCID: PMC10642809 DOI: 10.1098/rsta.2022.0201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Accepted: 05/09/2023] [Indexed: 10/10/2023]
Abstract
The permafrost region has accumulated organic carbon in cold and waterlogged soils over thousands of years and now contains three times as much carbon as the atmosphere. Global warming is degrading permafrost with the potential to accelerate climate change as increased microbial decomposition releases soil carbon as greenhouse gases. A 19-year time series of soil and ecosystem respiration radiocarbon from Alaska provides long-term insight into changing permafrost soil carbon dynamics in a warmer world. Nine per cent of ecosystem respiration and 23% of soil respiration observations had radiocarbon values more than 50‰ lower than the atmospheric value. Furthermore, the overall trend of ecosystem and soil respiration radiocarbon values through time decreased more than atmospheric radiocarbon values did, indicating that old carbon degradation was enhanced. Boosted regression tree analyses showed that temperature and moisture environmental variables had the largest relative influence on lower radiocarbon values. This suggested that old carbon degradation was controlled by warming/permafrost thaw and soil drying together, as waterlogged soil conditions could protect soil carbon from microbial decomposition even when thawed. Overall, changing conditions increasingly favoured the release of old carbon, which is a definitive fingerprint of an accelerating feedback to climate change as a consequence of warming and permafrost destabilization. This article is part of the Theo Murphy meeting issue 'Radiocarbon in the Anthropocene'.
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Affiliation(s)
- Edward A. G. Schuur
- Center for Ecosystem Science and Society, and Department of Biological Sciences, Northern Arizona University, Flagstaff, AZ 86011, USA
| | - Caitlin Hicks Pries
- Department of Biological Sciences, Dartmouth College, Hanover, NH 03755, USA
| | - Marguerite Mauritz
- Biological Sciences, University of Texas at El Paso, 500 West University Avenue, El Paso, TX 79902, USA
| | - Elaine Pegoraro
- Climate and Ecosystem Sciences Division, Lawrence Berkeley National Lab, Berkeley, CA, USA
| | | | - Craig See
- Center for Ecosystem Science and Society, and Department of Biological Sciences, Northern Arizona University, Flagstaff, AZ 86011, USA
| | - Chris Ebert
- Center for Ecosystem Science and Society, and Department of Biological Sciences, Northern Arizona University, Flagstaff, AZ 86011, USA
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2
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Rodenhizer H, Natali SM, Mauritz M, Taylor MA, Celis G, Kadej S, Kelley AK, Lathrop ER, Ledman J, Pegoraro EF, Salmon VG, Schädel C, See C, Webb EE, Schuur EAG. Abrupt permafrost thaw drives spatially heterogeneous soil moisture and carbon dioxide fluxes in upland tundra. GLOBAL CHANGE BIOLOGY 2023; 29:6286-6302. [PMID: 37694963 DOI: 10.1111/gcb.16936] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Revised: 08/16/2023] [Accepted: 08/27/2023] [Indexed: 09/12/2023]
Abstract
Permafrost thaw causes the seasonally thawed active layer to deepen, causing the Arctic to shift toward carbon release as soil organic matter becomes susceptible to decomposition. Ground subsidence initiated by ice loss can cause these soils to collapse abruptly, rapidly shifting soil moisture as microtopography changes and also accelerating carbon and nutrient mobilization. The uncertainty of soil moisture trajectories during thaw makes it difficult to predict the role of abrupt thaw in suppressing or exacerbating carbon losses. In this study, we investigated the role of shifting soil moisture conditions on carbon dioxide fluxes during a 13-year permafrost warming experiment that exhibited abrupt thaw. Warming deepened the active layer differentially across treatments, leading to variable rates of subsidence and formation of thermokarst depressions. In turn, differential subsidence caused a gradient of moisture conditions, with some plots becoming consistently inundated with water within thermokarst depressions and others exhibiting generally dry, but more variable soil moisture conditions outside of thermokarst depressions. Experimentally induced permafrost thaw initially drove increasing rates of growing season gross primary productivity (GPP), ecosystem respiration (Reco ), and net ecosystem exchange (NEE) (higher carbon uptake), but the formation of thermokarst depressions began to reverse this trend with a high level of spatial heterogeneity. Plots that subsided at the slowest rate stayed relatively dry and supported higher CO2 fluxes throughout the 13-year experiment, while plots that subsided very rapidly into the center of a thermokarst feature became consistently wet and experienced a rapid decline in growing season GPP, Reco , and NEE (lower carbon uptake or carbon release). These findings indicate that Earth system models, which do not simulate subsidence and often predict drier active layer conditions, likely overestimate net growing season carbon uptake in abruptly thawing landscapes.
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Affiliation(s)
- Heidi Rodenhizer
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, Arizona, USA
| | - Susan M Natali
- Woodwell Climate Research Center, Falmouth, Massachusetts, USA
| | - Marguerite Mauritz
- Biological Sciences, University of Texas at El Paso, El Paso, Texas, USA
| | - Meghan A Taylor
- CliC International Project Office, World Climate Research Program, Department of Earth, Geographic and Climate Sciences, University of Massachusetts, Amherst, Massachusetts, USA
| | - Gerardo Celis
- Department of Anthropology, University of Arkansas, Fayetteville, Arkansas, USA
| | - Stephanie Kadej
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, Arizona, USA
| | - Allison K Kelley
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, Arizona, USA
| | - Emma R Lathrop
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, Arizona, USA
| | - Justin Ledman
- Bonanza Creek Long Term Ecological Research Site, University of Alaska Fairbanks, Fairbanks, Alaska, USA
| | - Elaine F Pegoraro
- Climate and Ecosystem Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Verity G Salmon
- Environmental Science Division and Climate Change Science Institute, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA
| | - Christina Schädel
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, Arizona, USA
| | - Craig See
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, Arizona, USA
| | - Elizabeth E Webb
- School of Natural Resources and Environment, University of Florida, Gainesville, Florida, USA
| | - Edward A G Schuur
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, Arizona, USA
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3
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Virkkala AM, Aalto J, Rogers BM, Tagesson T, Treat CC, Natali SM, Watts JD, Potter S, Lehtonen A, Mauritz M, Schuur EAG, Kochendorfer J, Zona D, Oechel W, Kobayashi H, Humphreys E, Goeckede M, Iwata H, Lafleur PM, Euskirchen ES, Bokhorst S, Marushchak M, Martikainen PJ, Elberling B, Voigt C, Biasi C, Sonnentag O, Parmentier FJW, Ueyama M, Celis G, St Louis VL, Emmerton CA, Peichl M, Chi J, Järveoja J, Nilsson MB, Oberbauer SF, Torn MS, Park SJ, Dolman H, Mammarella I, Chae N, Poyatos R, López-Blanco E, Christensen TR, Kwon MJ, Sachs T, Holl D, Luoto M. Statistical upscaling of ecosystem CO 2 fluxes across the terrestrial tundra and boreal domain: Regional patterns and uncertainties. GLOBAL CHANGE BIOLOGY 2021; 27:4040-4059. [PMID: 33913236 DOI: 10.1111/gcb.15659] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Accepted: 03/05/2021] [Indexed: 06/12/2023]
Abstract
The regional variability in tundra and boreal carbon dioxide (CO2 ) fluxes can be high, complicating efforts to quantify sink-source patterns across the entire region. Statistical models are increasingly used to predict (i.e., upscale) CO2 fluxes across large spatial domains, but the reliability of different modeling techniques, each with different specifications and assumptions, has not been assessed in detail. Here, we compile eddy covariance and chamber measurements of annual and growing season CO2 fluxes of gross primary productivity (GPP), ecosystem respiration (ER), and net ecosystem exchange (NEE) during 1990-2015 from 148 terrestrial high-latitude (i.e., tundra and boreal) sites to analyze the spatial patterns and drivers of CO2 fluxes and test the accuracy and uncertainty of different statistical models. CO2 fluxes were upscaled at relatively high spatial resolution (1 km2 ) across the high-latitude region using five commonly used statistical models and their ensemble, that is, the median of all five models, using climatic, vegetation, and soil predictors. We found the performance of machine learning and ensemble predictions to outperform traditional regression methods. We also found the predictive performance of NEE-focused models to be low, relative to models predicting GPP and ER. Our data compilation and ensemble predictions showed that CO2 sink strength was larger in the boreal biome (observed and predicted average annual NEE -46 and -29 g C m-2 yr-1 , respectively) compared to tundra (average annual NEE +10 and -2 g C m-2 yr-1 ). This pattern was associated with large spatial variability, reflecting local heterogeneity in soil organic carbon stocks, climate, and vegetation productivity. The terrestrial ecosystem CO2 budget, estimated using the annual NEE ensemble prediction, suggests the high-latitude region was on average an annual CO2 sink during 1990-2015, although uncertainty remains high.
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Affiliation(s)
- Anna-Maria Virkkala
- Department of Geosciences and Geography, Faculty of Science, University of Helsinki, Helsinki, Finland
- Woodwell Climate Research Center, Falmouth, MA, USA
| | - Juha Aalto
- Department of Geosciences and Geography, Faculty of Science, University of Helsinki, Helsinki, Finland
- Weather and Climate Change Impact Research, Finnish Meteorological Institute, Helsinki, Finland
| | | | - Torbern Tagesson
- Department of Physical Geography and Ecosystem Science, Lund University, Lund, Sweden
- Department of Geosciences and Natural Resource Management, Copenhagen University, Copenhagen, Denmark
| | - Claire C Treat
- Alfred Wegener Institute Helmholtz Center for Polar and Marine Research, Potsdam, Germany
| | | | | | | | | | | | - Edward A G Schuur
- Center for Ecosystem Science and Society, Department of Biological Sciences, Northern Arizona University, Flagstaff, AZ, USA
| | - John Kochendorfer
- Atmosperic Turbulence and Diffusion Division of NOAA's Air Resources Laboratory, Oak Ridge, TN, USA
| | - Donatella Zona
- San Diego State University, San Diego, CA, USA
- University of Sheffield, Sheffield, UK
| | - Walter Oechel
- San Diego State University, San Diego, CA, USA
- University of Exeter, Exeter, UK
| | - Hideki Kobayashi
- Research Institute for Global Change, Japan Agency for Marine-Earth Science and Technology, Yokoama, Japan
| | | | - Mathias Goeckede
- Dept. Biogeochemical Signals, Max Planck Institute for Biogeochemistry, Jena, Germany
| | - Hiroki Iwata
- Department of Environmental Science, Shinshu University, Matsumoto, Japan
| | - Peter M Lafleur
- School of the Environment, Trent University, Peterborough, ON, Canada
| | | | - Stef Bokhorst
- Vrije Universiteit Amsterdam, Amsterdam, the Netherlands
| | - Maija Marushchak
- Department of Biological and Environmental Science, University of Jyväskylä, Jyväskylä, Finland
- Department of Environmental and Biological Sciences, University of Eastern Finland, Kuopio, Finland
| | - Pertti J Martikainen
- Department of Environmental and Biological Sciences, University of Eastern Finland, Kuopio, Finland
| | - Bo Elberling
- Center for Permafrost, Department of Geoscience and Natural Resource Management, University of Copenhagen, Copenhagen, Denmark
| | - Carolina Voigt
- Department of Environmental and Biological Sciences, University of Eastern Finland, Kuopio, Finland
- Département de géographie, Université de Montréal, Montréal, QC, Canada
| | - Christina Biasi
- Department of Environmental and Biological Sciences, University of Eastern Finland, Kuopio, Finland
| | - Oliver Sonnentag
- Département de géographie, Université de Montréal, Montréal, QC, Canada
| | - Frans-Jan W Parmentier
- Department of Physical Geography and Ecosystem Science, Lund University, Lund, Sweden
- Centre for Biogeochemistry in the Anthropocene, Department of Geosciences, University of Oslo, Oslo, Norway
| | - Masahito Ueyama
- Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Sakai, Japan
| | - Gerardo Celis
- Agronomy Department, University of Florida, Gainesville, FL, USA
| | - Vincent L St Louis
- Department of Biological Sciences, University of Alberta, Edmonton, AB, Canada
| | - Craig A Emmerton
- Department of Biological Sciences, University of Alberta, Edmonton, AB, Canada
| | - Matthias Peichl
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, Umeå, Sweden
| | - Jinshu Chi
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, Umeå, Sweden
| | - Järvi Järveoja
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, Umeå, Sweden
| | - Mats B Nilsson
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, Umeå, Sweden
| | - Steven F Oberbauer
- Department of Biological Sciences, Florida International University, Miami, FL, USA
| | | | - Sang-Jong Park
- Division of Atmospheric Sciences, Korea Polar Research Institute, Incheon, Republic of Korea
| | - Han Dolman
- Department of Earth Sciences, Free University Amsterdam, Amsterdam, the Netherlands
| | - Ivan Mammarella
- Institute for Atmospheric and Earth System Research/Physics, Faculty of Science, University of Helsinki, Helsinki, Finland
| | - Namyi Chae
- Institute of Life Science and Natural Resources, Korea University, Seoul, Republic of Korea
| | - Rafael Poyatos
- CREAF, Catalonia, Spain
- Universitat Autònoma de Barcelona, Catalonia, Spain
| | - Efrén López-Blanco
- Department of Environment and Minerals, Greenland Institute of Natural Resources, Nuuk, Greenland
- Department of Bioscience, Arctic Research Center, Aarhus University, Roskilde, Denmark
| | | | - Min Jung Kwon
- Laboratoire des Sciences du Climat et de l'Environnement, Gif-sur-Yvette, France
- Division of Life Sciences, Korea Polar Research Institute, Incheon, Republic of Korea
| | - Torsten Sachs
- GFZ German Research Centre for Geosciences, Potsdam, Germany
| | - David Holl
- Center for Earth System Research and Sustainability (CEN), University of Hamburg, Hamburg, Germany
| | - Miska Luoto
- Department of Geosciences and Geography, Faculty of Science, University of Helsinki, Helsinki, Finland
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4
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In 't Zandt MH, Liebner S, Welte CU. Roles of Thermokarst Lakes in a Warming World. Trends Microbiol 2020; 28:769-779. [PMID: 32362540 DOI: 10.1016/j.tim.2020.04.002] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 02/10/2020] [Accepted: 04/01/2020] [Indexed: 11/27/2022]
Abstract
Permafrost covers a quarter of the northern hemisphere land surface and contains twice the amount of carbon that is currently present in the atmosphere. Future climate change is expected to reduce its near-surface cover by over 90% by the end of the 21st century, leading to thermokarst lake formation. Thermokarst lakes are point sources of carbon dioxide and methane which release long-term carbon stocks into the atmosphere, thereby initiating a positive climate feedback potentially contributing up to a 0.39°C rise of surface air temperatures by 2300. This review describes the potential role of thermokarst lakes in a warming world and the microbial mechanisms that underlie their contributions to the global greenhouse gas budget.
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Affiliation(s)
- Michiel H In 't Zandt
- Department of Microbiology, Institute for Water and Wetland Research, Radboud University, Heyendaalseweg 135, 6525 AJ, Nijmegen, the Netherlands; Netherlands Earth System Science Center, Utrecht University, Heidelberglaan 2, 3584 CS, Utrecht, the Netherlands
| | - Susanne Liebner
- GFZ German Research Centre for Geosciences, Section 3.7 Geomicrobiology, Telegrafenberg, 14473 Potsdam, Germany; University of Potsdam, Institute of Biochemistry and Biology, 14469 Potsdam, Germany
| | - Cornelia U Welte
- Department of Microbiology, Institute for Water and Wetland Research, Radboud University, Heyendaalseweg 135, 6525 AJ, Nijmegen, the Netherlands; Soehngen Institute of Anaerobic Microbiology, Radboud University, Heyendaalseweg 135, 6525 AJ, Nijmegen, the Netherlands.
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5
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Hewitt RE, DeVan MR, Lagutina IV, Genet H, McGuire AD, Taylor DL, Mack MC. Mycobiont contribution to tundra plant acquisition of permafrost-derived nitrogen. THE NEW PHYTOLOGIST 2020; 226:126-141. [PMID: 31580482 DOI: 10.1111/nph.16235] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Accepted: 09/26/2019] [Indexed: 05/27/2023]
Abstract
As Arctic soils warm, thawed permafrost releases nitrogen (N) that could stimulate plant productivity and thus offset soil carbon losses from tundra ecosystems. Although mycorrhizal fungi could facilitate plant access to permafrost-derived N, their exploration capacity beyond host plant root systems into deep, cold active layer soils adjacent to the permafrost table is unknown. We characterized root-associated fungi (RAF) that colonized ericoid (ERM) and ectomycorrhizal (ECM) shrub roots and occurred below the maximum rooting depth in permafrost thaw-front soil in tussock and shrub tundra communities. We explored the relationships between root and thaw front fungal composition and plant uptake of a 15 N tracer applied at the permafrost boundary. We show that ERM and ECM shrubs associate with RAF at the thaw front providing evidence for potential mycelial connectivity between roots and the permafrost boundary. Among shrubs and tundra communities, RAF connectivity to the thaw boundary was ubiquitous. The occurrence of particular RAF in both roots and thaw front soil was positively correlated with 15 N recovered in shrub biomass Taxon-specific RAF associations could be a mechanism for the vertical redistribution of deep, permafrost-derived nutrients, which may alleviate N limitation and stimulate productivity in warming tundra.
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Affiliation(s)
- Rebecca E Hewitt
- Center for Ecosystem Science and Society, Northern Arizona University, PO Box 5620, Flagstaff, AZ, 86011, USA
| | - M Rae DeVan
- Department of Biology, MSC03 2020, University of New Mexico, Albuquerque, NM, 87131, USA
| | - Irina V Lagutina
- Department of Biology, MSC03 2020, University of New Mexico, Albuquerque, NM, 87131, USA
| | - Helene Genet
- Institute of Arctic Biology, University of Alaska Fairbanks, PO Box 757000, Fairbanks, AK, 99775, USA
| | - A David McGuire
- Institute of Arctic Biology, University of Alaska Fairbanks, PO Box 757000, Fairbanks, AK, 99775, USA
| | - D Lee Taylor
- Department of Biology, MSC03 2020, University of New Mexico, Albuquerque, NM, 87131, USA
| | - Michelle C Mack
- Center for Ecosystem Science and Society, Northern Arizona University, PO Box 5620, Flagstaff, AZ, 86011, USA
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6
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Zhou YM, Meng GL, Tai ZJ, Han JQ, Deng JF, Wang HW, Li MH. Effects of Experimental Warming on Growing Season Temperature and Carbon Exchange in an Alpine Tundra Ecosystem. RUSS J ECOL+ 2019. [DOI: 10.1134/s1067413619050138] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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7
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Loranty MM, Berner LT, Taber ED, Kropp H, Natali SM, Alexander HD, Davydov SP, Zimov NS. Understory vegetation mediates permafrost active layer dynamics and carbon dioxide fluxes in open-canopy larch forests of northeastern Siberia. PLoS One 2018; 13:e0194014. [PMID: 29565980 PMCID: PMC5863986 DOI: 10.1371/journal.pone.0194014] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2017] [Accepted: 02/22/2018] [Indexed: 11/25/2022] Open
Abstract
Arctic ecosystems are characterized by a broad range of plant functional types that are highly heterogeneous at small (~1–2 m) spatial scales. Climatic changes can impact vegetation distribution directly, and also indirectly via impacts on disturbance regimes. Consequent changes in vegetation structure and function have implications for surface energy dynamics that may alter permafrost thermal dynamics, and are therefore of interest in the context of permafrost related climate feedbacks. In this study we examine small-scale heterogeneity in soil thermal properties and ecosystem carbon and water fluxes associated with varying understory vegetation in open-canopy larch forests in northeastern Siberia. We found that lichen mats comprise 16% of understory vegetation cover on average in open canopy larch forests, and lichen abundance was inversely related to canopy cover. Relative to adjacent areas dominated by shrubs and moss, lichen mats had 2–3 times deeper permafrost thaw depths and surface soils warmer by 1–2°C in summer and less than 1°C in autumn. Despite deeper thaw depths, ecosystem respiration did not differ across vegetation types, indicating that autotrophic respiration likely dominates areas with shrubs and moss. Summertime net ecosystem exchange of CO2 was negative (i.e. net uptake) in areas with high shrub cover, while positive (i.e. net loss) in lichen mats and areas with less shrub cover. Our results highlight relationships between vegetation and soil thermal dynamics in permafrost ecosystems, and underscore the necessity of considering both vegetation and permafrost dynamics in shaping carbon cycling in permafrost ecosystems.
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Affiliation(s)
- Michael M. Loranty
- Department of Geography, Colgate University, Hamilton, NY United States of America
- * E-mail:
| | - Logan T. Berner
- School of Informatics, Computing, and Cyber Systems, Northern Arizona University, Flagstaff, AZ United States of America
| | - Eric D. Taber
- Department of Geography, Colgate University, Hamilton, NY United States of America
| | - Heather Kropp
- Department of Geography, Colgate University, Hamilton, NY United States of America
| | - Susan M. Natali
- Woods Hole Research Center, Falmouth, MA United States of America
| | - Heather D. Alexander
- Department of Forestry, Forest and Wildlife Research Center, Mississippi State University, Mississippi State, MS United States of America
| | - Sergey P. Davydov
- Northeast Science Station, Pacific Institute for Geography, Far East Branch, Russian Academy of Sciences, Cherskii, Republic of Sakha, Yakutia, Russia
| | - Nikita S. Zimov
- Northeast Science Station, Pacific Institute for Geography, Far East Branch, Russian Academy of Sciences, Cherskii, Republic of Sakha, Yakutia, Russia
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8
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Yuan MM, Zhang J, Xue K, Wu L, Deng Y, Deng J, Hale L, Zhou X, He Z, Yang Y, Van Nostrand JD, Schuur EAG, Konstantinidis KT, Penton CR, Cole JR, Tiedje JM, Luo Y, Zhou J. Microbial functional diversity covaries with permafrost thaw-induced environmental heterogeneity in tundra soil. GLOBAL CHANGE BIOLOGY 2018; 24:297-307. [PMID: 28715138 DOI: 10.1111/gcb.13820] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Accepted: 07/06/2017] [Indexed: 05/27/2023]
Abstract
Permafrost soil in high latitude tundra is one of the largest terrestrial carbon (C) stocks and is highly sensitive to climate warming. Understanding microbial responses to warming-induced environmental changes is critical to evaluating their influences on soil biogeochemical cycles. In this study, a functional gene array (i.e., geochip 4.2) was used to analyze the functional capacities of soil microbial communities collected from a naturally degrading permafrost region in Central Alaska. Varied thaw history was reported to be the main driver of soil and plant differences across a gradient of minimally, moderately, and extensively thawed sites. Compared with the minimally thawed site, the number of detected functional gene probes across the 15-65 cm depth profile at the moderately and extensively thawed sites decreased by 25% and 5%, while the community functional gene β-diversity increased by 34% and 45%, respectively, revealing decreased functional gene richness but increased community heterogeneity along the thaw progression. Particularly, the moderately thawed site contained microbial communities with the highest abundances of many genes involved in prokaryotic C degradation, ammonification, and nitrification processes, but lower abundances of fungal C decomposition and anaerobic-related genes. Significant correlations were observed between functional gene abundance and vascular plant primary productivity, suggesting that plant growth and species composition could be co-evolving traits together with microbial community composition. Altogether, this study reveals the complex responses of microbial functional potentials to thaw-related soil and plant changes and provides information on potential microbially mediated biogeochemical cycles in tundra ecosystems.
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Affiliation(s)
- Mengting M Yuan
- Institute for Environmental Genomics, University of Oklahoma, Norman, OK, USA
- Department of Microbiology and Plant Biology, University of Oklahoma, Norman, OK, USA
| | - Jin Zhang
- Institute for Environmental Genomics, University of Oklahoma, Norman, OK, USA
- Department of Microbiology and Plant Biology, University of Oklahoma, Norman, OK, USA
| | - Kai Xue
- Institute for Environmental Genomics, University of Oklahoma, Norman, OK, USA
- Department of Microbiology and Plant Biology, University of Oklahoma, Norman, OK, USA
- University of Chinese Academy of Sciences, Beijing, China
| | - Liyou Wu
- Institute for Environmental Genomics, University of Oklahoma, Norman, OK, USA
- Department of Microbiology and Plant Biology, University of Oklahoma, Norman, OK, USA
| | - Ye Deng
- Institute for Environmental Genomics, University of Oklahoma, Norman, OK, USA
- Department of Microbiology and Plant Biology, University of Oklahoma, Norman, OK, USA
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, China
| | - Jie Deng
- Institute for Environmental Genomics, University of Oklahoma, Norman, OK, USA
- Department of Microbiology and Plant Biology, University of Oklahoma, Norman, OK, USA
- School of Ecological and Environmental Sciences, East China Normal University, Shanghai, China
| | - Lauren Hale
- Institute for Environmental Genomics, University of Oklahoma, Norman, OK, USA
- Department of Microbiology and Plant Biology, University of Oklahoma, Norman, OK, USA
| | - Xishu Zhou
- Institute for Environmental Genomics, University of Oklahoma, Norman, OK, USA
- Department of Microbiology and Plant Biology, University of Oklahoma, Norman, OK, USA
- School of Minerals Processing and Bioengineering, Central South University, Changsha, China
| | - Zhili He
- Institute for Environmental Genomics, University of Oklahoma, Norman, OK, USA
- Department of Microbiology and Plant Biology, University of Oklahoma, Norman, OK, USA
| | - Yunfeng Yang
- School of Environment, Tsinghua University, Beijing, China
| | - Joy D Van Nostrand
- Institute for Environmental Genomics, University of Oklahoma, Norman, OK, USA
- Department of Microbiology and Plant Biology, University of Oklahoma, Norman, OK, USA
| | - Edward A G Schuur
- Center for Ecosystem Sciences and Society, Department of Biological Sciences, Northern Arizona University, Flagstaff, AZ, USA
| | - Konstantinos T Konstantinidis
- School of Civil and Environmental Engineering, School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA, USA
| | - Christopher R Penton
- College of Integrative Sciences and Arts, Arizona State University, Mesa, AZ, USA
| | - James R Cole
- Center for Microbial Ecology, Michigan State University, East Lansing, MI, USA
| | - James M Tiedje
- Center for Microbial Ecology, Michigan State University, East Lansing, MI, USA
| | - Yiqi Luo
- Department of Microbiology and Plant Biology, University of Oklahoma, Norman, OK, USA
| | - Jizhong Zhou
- Institute for Environmental Genomics, University of Oklahoma, Norman, OK, USA
- Department of Microbiology and Plant Biology, University of Oklahoma, Norman, OK, USA
- School of Environment, Tsinghua University, Beijing, China
- School of Civil Engineering and Environmental Sciences, University of Oklahoma, Norman, OK, USA
- Earth and Environmental Sciences, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
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9
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Mauritz M, Bracho R, Celis G, Hutchings J, Natali SM, Pegoraro E, Salmon VG, Schädel C, Webb EE, Schuur EAG. Nonlinear CO 2 flux response to 7 years of experimentally induced permafrost thaw. GLOBAL CHANGE BIOLOGY 2017; 23:3646-3666. [PMID: 28208232 DOI: 10.1111/gcb.13661] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2016] [Accepted: 01/19/2017] [Indexed: 06/06/2023]
Abstract
Rapid Arctic warming is expected to increase global greenhouse gas concentrations as permafrost thaw exposes immense stores of frozen carbon (C) to microbial decomposition. Permafrost thaw also stimulates plant growth, which could offset C loss. Using data from 7 years of experimental Air and Soil warming in moist acidic tundra, we show that Soil warming had a much stronger effect on CO2 flux than Air warming. Soil warming caused rapid permafrost thaw and increased ecosystem respiration (Reco ), gross primary productivity (GPP), and net summer CO2 storage (NEE). Over 7 years Reco , GPP, and NEE also increased in Control (i.e., ambient plots), but this change could be explained by slow thaw in Control areas. In the initial stages of thaw, Reco , GPP, and NEE increased linearly with thaw across all treatments, despite different rates of thaw. As thaw in Soil warming continued to increase linearly, ground surface subsidence created saturated microsites and suppressed Reco , GPP, and NEE. However Reco and GPP remained high in areas with large Eriophorum vaginatum biomass. In general NEE increased with thaw, but was more strongly correlated with plant biomass than thaw, indicating that higher Reco in deeply thawed areas during summer months was balanced by GPP. Summer CO2 flux across treatments fit a single quadratic relationship that captured the functional response of CO2 flux to thaw, water table depth, and plant biomass. These results demonstrate the importance of indirect thaw effects on CO2 flux: plant growth and water table dynamics. Nonsummer Reco models estimated that the area was an annual CO2 source during all years of observation. Nonsummer CO2 loss in warmer, more deeply thawed soils exceeded the increases in summer GPP, and thawed tundra was a net annual CO2 source.
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Affiliation(s)
- Marguerite Mauritz
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, AZ, USA
| | - Rosvel Bracho
- School of Forest Resources and Conservation, University of Florida, Gainesville, FL, USA
| | - Gerardo Celis
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, AZ, USA
| | - Jack Hutchings
- Department of Geological Sciences, University of Florida, Gainesville, FL, USA
| | | | - Elaine Pegoraro
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, AZ, USA
| | - Verity G Salmon
- Environmental Sciences Division and Climate Change Sciences Institute, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - Christina Schädel
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, AZ, USA
| | - Elizabeth E Webb
- Department of Biology, University of Florida, Gainesville, FL, USA
| | - Edward A G Schuur
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, AZ, USA
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10
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Penton CR, Yang C, Wu L, Wang Q, Zhang J, Liu F, Qin Y, Deng Y, Hemme CL, Zheng T, Schuur EAG, Tiedje J, Zhou J. NifH-Harboring Bacterial Community Composition across an Alaskan Permafrost Thaw Gradient. Front Microbiol 2016; 7:1894. [PMID: 27933054 PMCID: PMC5121533 DOI: 10.3389/fmicb.2016.01894] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2016] [Accepted: 11/11/2016] [Indexed: 11/13/2022] Open
Abstract
Since nitrogen (N) is often limiting in permafrost soils, we investigated the N2-fixing genetic potential and the inferred taxa harboring those genes by sequencing nifH gene fragments in samples taken along a permafrost thaw gradient in an Alaskan boreal soil. Samples from minimally, moderately and extensively thawed sites were taken to a depth of 79 cm to encompass zones above and below the depth of the water table. NifH reads were translated with frameshift correction and 112,476 sequences were clustered at 5% amino acid dissimilarity resulting in 1,631 OTUs. Sample depth in relation to water table depth was correlated to differences in the NifH sequence classes with those most closely related to group I nifH-harboring Alpha- and Beta-Proteobacteria in higher abundance above water table depth while those related to group III nifH-harboring Delta Proteobacteria more abundant below. The most dominant below water table depth NifH sequences, comprising 1/3 of the total, were distantly related to Verrucomicrobia-Opitutaceae. Overall, these results suggest that permafrost thaw alters the class-level composition of N2-fixing communities in the thawed soil layers and that this distinction corresponds to the depth of the water table. These nifH data were also compared to nifH sequences obtained from a study at an Alaskan taiga site, and to those of other geographically distant, non-permafrost sites. The two Alaska sites were differentiated largely by changes in relative abundances of the same OTUs, whereas the non-Alaska sites were differentiated by the lack of many Alaskan OTUs, and the presence of unique halophilic, sulfate- and iron-reducing taxa in the Alaska sites.
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Affiliation(s)
- C. Ryan Penton
- College of Integrative Sciences and Arts, Arizona State UniversityMesa, AZ, USA
- Arizona State University, Center for Fundamental and Applied Microbiomics, Biodesign InstituteTempe, AZ, USA
| | - Caiyun Yang
- Department of Microbiology and Plant Biology, Institute for Environmental Genomics, University of OklahomaNorman, OK, USA
- Key Lab of the Ministry of Education for Coastal and Wetland Ecosystems, School of Environmental Sciences, Xiamen UniversityXiamen, China
| | - Liyou Wu
- Department of Microbiology and Plant Biology, Institute for Environmental Genomics, University of OklahomaNorman, OK, USA
| | - Qiong Wang
- Center for Microbial Ecology, Michigan State UniversityEast Lansing, MI, USA
| | - Jin Zhang
- Department of Microbiology and Plant Biology, Institute for Environmental Genomics, University of OklahomaNorman, OK, USA
| | - Feifei Liu
- Department of Microbiology and Plant Biology, Institute for Environmental Genomics, University of OklahomaNorman, OK, USA
| | - Yujia Qin
- Department of Microbiology and Plant Biology, Institute for Environmental Genomics, University of OklahomaNorman, OK, USA
| | - Ye Deng
- Department of Microbiology and Plant Biology, Institute for Environmental Genomics, University of OklahomaNorman, OK, USA
| | - Christopher L. Hemme
- Department of Microbiology and Plant Biology, Institute for Environmental Genomics, University of OklahomaNorman, OK, USA
| | - Tianling Zheng
- Key Lab of the Ministry of Education for Coastal and Wetland Ecosystems, School of Environmental Sciences, Xiamen UniversityXiamen, China
| | - Edward A. G. Schuur
- Department of Biological Sciences, Northern Arizona UniversityFlagstaff, AZ, USA
| | - James Tiedje
- Center for Microbial Ecology, Michigan State UniversityEast Lansing, MI, USA
| | - Jizhong Zhou
- Department of Microbiology and Plant Biology, Institute for Environmental Genomics, University of OklahomaNorman, OK, USA
- Earth Sciences Division, Lawrence Berkeley National LaboratoryBerkeley, CA, USA
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua UniversityBeijing, China
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11
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Salmon VG, Soucy P, Mauritz M, Celis G, Natali SM, Mack MC, Schuur EAG. Nitrogen availability increases in a tundra ecosystem during five years of experimental permafrost thaw. GLOBAL CHANGE BIOLOGY 2016; 22:1927-1941. [PMID: 26718892 DOI: 10.1111/gcb.13204] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Revised: 11/19/2015] [Accepted: 12/01/2015] [Indexed: 06/05/2023]
Abstract
Perennially frozen soil in high latitude ecosystems (permafrost) currently stores 1330-1580 Pg of carbon (C). As these ecosystems warm, the thaw and decomposition of permafrost is expected to release large amounts of C to the atmosphere. Fortunately, losses from the permafrost C pool will be partially offset by increased plant productivity. The degree to which plants are able to sequester C, however, will be determined by changing nitrogen (N) availability in these thawing soil profiles. N availability currently limits plant productivity in tundra ecosystems but plant access to N is expected improve as decomposition increases in speed and extends to deeper soil horizons. To evaluate the relationship between permafrost thaw and N availability, we monitored N cycling during 5 years of experimentally induced permafrost thaw at the Carbon in Permafrost Experimental Heating Research (CiPEHR) project. Inorganic N availability increased significantly in response to deeper thaw and greater soil moisture induced by Soil warming. This treatment also prompted a 23% increase in aboveground biomass and a 49% increase in foliar N pools. The sedge Eriophorum vaginatum responded most strongly to warming: this species explained 91% of the change in aboveground biomass during the 5 year period. Air warming had little impact when applied alone, but when applied in combination with Soil warming, growing season soil inorganic N availability was significantly reduced. These results demonstrate that there is a strong positive relationship between the depth of permafrost thaw and N availability in tundra ecosystems but that this relationship can be diminished by interactions between increased thaw, warmer air temperatures, and higher levels of soil moisture. Within 5 years of permafrost thaw, plants actively incorporate newly available N into biomass but C storage in live vascular plant biomass is unlikely to be greater than losses from deep soil C pools.
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Affiliation(s)
- Verity G Salmon
- Biology Department, University of Florida, Gainesville, FL, 32611, USA
| | - Patrick Soucy
- Biology Department, University of Florida, Gainesville, FL, 32611, USA
| | - Marguerite Mauritz
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, AZ, 86011, USA
| | - Gerardo Celis
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, AZ, 86011, USA
| | | | - Michelle C Mack
- Biology Department, University of Florida, Gainesville, FL, 32611, USA
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, AZ, 86011, USA
| | - Edward A G Schuur
- Biology Department, University of Florida, Gainesville, FL, 32611, USA
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, AZ, 86011, USA
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12
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Hicks Pries CE, van Logtestijn RSP, Schuur EAG, Natali SM, Cornelissen JHC, Aerts R, Dorrepaal E. Decadal warming causes a consistent and persistent shift from heterotrophic to autotrophic respiration in contrasting permafrost ecosystems. GLOBAL CHANGE BIOLOGY 2015; 21:4508-4519. [PMID: 26150277 DOI: 10.1111/gcb.13032] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2015] [Accepted: 06/10/2015] [Indexed: 06/04/2023]
Abstract
Soil carbon in permafrost ecosystems has the potential to become a major positive feedback to climate change if permafrost thaw increases heterotrophic decomposition. However, warming can also stimulate autotrophic production leading to increased ecosystem carbon storage-a negative climate change feedback. Few studies partitioning ecosystem respiration examine decadal warming effects or compare responses among ecosystems. Here, we first examined how 11 years of warming during different seasons affected autotrophic and heterotrophic respiration in a bryophyte-dominated peatland in Abisko, Sweden. We used natural abundance radiocarbon to partition ecosystem respiration into autotrophic respiration, associated with production, and heterotrophic decomposition. Summertime warming decreased the age of carbon respired by the ecosystem due to increased proportional contributions from autotrophic and young soil respiration and decreased proportional contributions from old soil. Summertime warming's large effect was due to not only warmer air temperatures during the growing season, but also to warmer deep soils year-round. Second, we compared ecosystem respiration responses between two contrasting ecosystems, the Abisko peatland and a tussock-dominated tundra in Healy, Alaska. Each ecosystem had two different timescales of warming (<5 years and over a decade). Despite the Abisko peatland having greater ecosystem respiration and larger contributions from heterotrophic respiration than the Healy tundra, both systems responded consistently to short- and long-term warming with increased respiration, increased autotrophic contributions to ecosystem respiration, and increased ratios of autotrophic to heterotrophic respiration. We did not detect an increase in old soil carbon losses with warming at either site. If increased autotrophic respiration is balanced by increased primary production, as is the case in the Healy tundra, warming will not cause these ecosystems to become growing season carbon sources. Warming instead causes a persistent shift from heterotrophic to more autotrophic control of the growing season carbon cycle in these carbon-rich permafrost ecosystems.
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Affiliation(s)
- Caitlin E Hicks Pries
- Earth Sciences Division, Climate Sciences Department, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA, 94720, USA
- Department of Biology, University of Florida, 220 Bartram Hall, Gainesville, FL, 32611, USA
| | - Richard S P van Logtestijn
- Department of Systems Ecology, Institute of Ecological Science, VU University Amsterdam, De Boelelaan 1085, NL-1081 HV, Amsterdam, the Netherlands
| | - Edward A G Schuur
- Department of Biology, University of Florida, 220 Bartram Hall, Gainesville, FL, 32611, USA
| | - Susan M Natali
- Department of Biology, University of Florida, 220 Bartram Hall, Gainesville, FL, 32611, USA
| | - Johannes H C Cornelissen
- Department of Systems Ecology, Institute of Ecological Science, VU University Amsterdam, De Boelelaan 1085, NL-1081 HV, Amsterdam, the Netherlands
| | - Rien Aerts
- Department of Systems Ecology, Institute of Ecological Science, VU University Amsterdam, De Boelelaan 1085, NL-1081 HV, Amsterdam, the Netherlands
| | - Ellen Dorrepaal
- Climate Impacts Research Centre, Department of Ecology and Environmental Science, Umeå University, S-981 07, Abisko, Sweden
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13
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Deng J, Gu Y, Zhang J, Xue K, Qin Y, Yuan M, Yin H, He Z, Wu L, Schuur EAG, Tiedje JM, Zhou J. Shifts of tundra bacterial and archaeal communities along a permafrost thaw gradient in
A
laska. Mol Ecol 2014; 24:222-34. [DOI: 10.1111/mec.13015] [Citation(s) in RCA: 92] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2014] [Revised: 11/03/2014] [Accepted: 11/20/2014] [Indexed: 11/29/2022]
Affiliation(s)
- Jie Deng
- Department of Microbiology and Plant Biology Institute for Environmental Genomics University of Oklahoma Norman OK USA
| | - Yunfu Gu
- Department of Microbiology and Plant Biology Institute for Environmental Genomics University of Oklahoma Norman OK USA
- College of Resource and Environment Sichuan Agricultural University Chengdu Sichuan China
| | - Jin Zhang
- Department of Microbiology and Plant Biology Institute for Environmental Genomics University of Oklahoma Norman OK USA
| | - Kai Xue
- Department of Microbiology and Plant Biology Institute for Environmental Genomics University of Oklahoma Norman OK USA
| | - Yujia Qin
- Department of Microbiology and Plant Biology Institute for Environmental Genomics University of Oklahoma Norman OK USA
| | - Mengting Yuan
- Department of Microbiology and Plant Biology Institute for Environmental Genomics University of Oklahoma Norman OK USA
| | - Huaqun Yin
- Department of Microbiology and Plant Biology Institute for Environmental Genomics University of Oklahoma Norman OK USA
- School of Mineral Processing and Bioengineering Central South University Changsha Hunan China
| | - Zhili He
- Department of Microbiology and Plant Biology Institute for Environmental Genomics University of Oklahoma Norman OK USA
| | - Liyou Wu
- Department of Microbiology and Plant Biology Institute for Environmental Genomics University of Oklahoma Norman OK USA
| | | | - James M. Tiedje
- Center for Microbial Ecology Michigan State University East Lansing MI USA
| | - Jizhong Zhou
- Department of Microbiology and Plant Biology Institute for Environmental Genomics University of Oklahoma Norman OK USA
- Earth Sciences Division Lawrence Berkeley National Laboratory Berkeley CA USA
- State Key Joint Laboratory of Environment Simulation and Pollution Control School of Environment Tsinghua University Beijing China
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14
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Natali SM, Schuur EAG, Webb EE, Pries CEH, Crummer KG. Permafrost degradation stimulates carbon loss from experimentally warmed tundra. Ecology 2014; 95:602-8. [DOI: 10.1890/13-0602.1] [Citation(s) in RCA: 105] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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15
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Heinemeyer A, Gornall J, Baxter R, Huntley B, Ineson P. Evaluating the carbon balance estimate from an automated ground-level flux chamber system in artificial grass mesocosms. Ecol Evol 2013; 3:4998-5010. [PMID: 24455131 PMCID: PMC3892363 DOI: 10.1002/ece3.879] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2013] [Revised: 10/10/2013] [Accepted: 10/15/2013] [Indexed: 11/16/2022] Open
Abstract
Measuring and modeling carbon (C) stock changes in terrestrial ecosystems are pivotal in addressing global C-cycling model uncertainties. Difficulties in detecting small short-term changes in relatively large C stocks require the development of robust sensitive flux measurement techniques. Net ecosystem exchange (NEE) ground-level chambers are increasingly used to assess C dynamics in low vegetation ecosystems but, to date, have lacked formal rigorous field validation against measured C stock changes. We developed and deployed an automated and multiplexed C-flux chamber system in grassland mesocosms in order rigorously to compare ecosystem total C budget obtained using hourly C-flux measurements versus destructive net C balance. The system combines transparent NEE and opaque respiration chambers enabling partitioning of photosynthetic and respiratory fluxes. The C-balance comparison showed good agreement between the two methods, but only after NEE fluxes were corrected for light reductions due to chamber presence. The dark chamber fluxes allowed assessing temperature sensitivity of ecosystem respiration (R eco) components (i.e., heterotrophic vs. autotrophic) at different growth stages. We propose that such automated flux chamber systems can provide an accurate C balance, also enabling pivotal partitioning of the different C-flux components (e.g., photosynthesis and respiration) suitable for model evaluation and developments.
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Affiliation(s)
- Andreas Heinemeyer
- Stockholm Environment Institute (SEI-York centre) at the Environment Department, University of YorkYork, YO10 5DD, UK
| | - Jemma Gornall
- Metoffice at the Hadley CentreFitzRoy Road, Exeter, EX1 3PB, UK
| | - Robert Baxter
- School of Biological and Biomedical Sciences, Durham UniversityDurham, DH1 3LE, UK
| | - Brian Huntley
- School of Biological and Biomedical Sciences, Durham UniversityDurham, DH1 3LE, UK
| | - Phil Ineson
- Stockholm Environment Institute (SEI-York centre) at the Environment Department, University of YorkYork, YO10 5DD, UK
- Department of Biology, University of YorkYork, YO10 5DD, UK
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16
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Hicks Pries CE, Schuur EAG, Crummer KG. Thawing permafrost increases old soil and autotrophic respiration in tundra: partitioning ecosystem respiration using δ(13) C and ∆(14) C. GLOBAL CHANGE BIOLOGY 2013; 19:649-661. [PMID: 23504799 DOI: 10.1111/gcb.12058] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2012] [Accepted: 09/27/2012] [Indexed: 06/01/2023]
Abstract
Ecosystem respiration (Reco ) is one of the largest terrestrial carbon (C) fluxes. The effect of climate change on Reco depends on the responses of its autotrophic and heterotrophic components. How autotrophic and heterotrophic respiration sources respond to climate change is especially important in ecosystems underlain by permafrost. Permafrost ecosystems contain vast stores of soil C (1672 Pg) and are located in northern latitudes where climate change is accelerated. Warming will cause a positive feedback to climate change if heterotrophic respiration increases without corresponding increases in primary production. We quantified the response of autotrophic and heterotrophic respiration to permafrost thaw across the 2008 and 2009 growing seasons. We partitioned Reco using Δ(14) C and δ(13) C into four sources-two autotrophic (above - and belowground plant structures) and two heterotrophic (young and old soil). We sampled the Δ(14) C and δ(13) C of sources using incubations and the Δ(14) C and δ(13) C of Reco using field measurements. We then used a Bayesian mixing model to solve for the most likely contributions of each source to Reco . Autotrophic respiration ranged from 40 to 70% of Reco and was greatest at the height of the growing season. Old soil heterotrophic respiration ranged from 6 to 18% of Reco and was greatest where permafrost thaw was deepest. Overall, growing season fluxes of autotrophic and old soil heterotrophic respiration increased as permafrost thaw deepened. Areas with greater thaw also had the greatest primary production. Warming in permafrost ecosystems therefore leads to increased plant and old soil respiration that is initially compensated by increased net primary productivity. However, barring large shifts in plant community composition, future increases in old soil respiration will likely outpace productivity, resulting in a positive feedback to climate change.
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17
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Nielsen UN, Wall DH. The future of soil invertebrate communities in polar regions: different climate change responses in the Arctic and Antarctic? Ecol Lett 2013; 16:409-19. [DOI: 10.1111/ele.12058] [Citation(s) in RCA: 89] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2012] [Revised: 09/13/2012] [Accepted: 11/26/2012] [Indexed: 11/28/2022]
Affiliation(s)
| | - Diana H. Wall
- Natural Resource Ecology Laboratory and Department of Biology; Colorado State University; Fort Collins; CO; 80523; USA
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18
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Trucco C, Schuur EAG, Natali SM, Belshe EF, Bracho R, Vogel J. Seven-year trends of CO2exchange in a tundra ecosystem affected by long-term permafrost thaw. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/2011jg001907] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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19
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Belshe EF, Schuur EAG, Bolker BM, Bracho R. Incorporating spatial heterogeneity created by permafrost thaw into a landscape carbon estimate. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/2011jg001836] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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20
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Hicks Pries CE, Schuur EAG, Crummer KG. Holocene Carbon Stocks and Carbon Accumulation Rates Altered in Soils Undergoing Permafrost Thaw. Ecosystems 2011. [DOI: 10.1007/s10021-011-9500-4] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2022]
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21
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Wolken JM, Hollingsworth TN, Rupp TS, Chapin FS, Trainor SF, Barrett TM, Sullivan PF, McGuire AD, Euskirchen ES, Hennon PE, Beever EA, Conn JS, Crone LK, D'Amore DV, Fresco N, Hanley TA, Kielland K, Kruse JJ, Patterson T, Schuur EAG, Verbyla DL, Yarie J. Evidence and implications of recent and projected climate change in Alaska's forest ecosystems. Ecosphere 2011. [DOI: 10.1890/es11-00288.1] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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22
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Lee H, Schuur EAG, Vogel JG. Soil CO2production in upland tundra where permafrost is thawing. ACTA ACUST UNITED AC 2010. [DOI: 10.1029/2008jg000906] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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