1
|
Heffernan L, Estop-Aragonés C, Kuhn MA, Holger-Knorr K, Olefeldt D. Changing climatic controls on the greenhouse gas balance of thermokarst bogs during succession after permafrost thaw. GLOBAL CHANGE BIOLOGY 2024; 30:e17388. [PMID: 38967139 DOI: 10.1111/gcb.17388] [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: 02/21/2024] [Revised: 05/19/2024] [Accepted: 06/10/2024] [Indexed: 07/06/2024]
Abstract
Permafrost thaw in northern peatlands causes collapse of permafrost peat plateaus and thermokarst bog development, with potential impacts on atmospheric greenhouse gas exchange. Here, we measured methane and carbon dioxide fluxes over 3 years (including winters) using static chambers along two permafrost thaw transects in northwestern Canada, spanning young (~30 years since thaw), intermediate and mature thermokarst bogs (~200 years since thaw). Young bogs were wetter, warmer and had more hydrophilic vegetation than mature bogs. Methane emissions increased with wetness and soil temperature (40 cm depth) and modelled annual estimates were greatest in the young bog during the warmest year and lowest in the mature bog during the coolest year (21 and 7 g C-CH4 m-2 year-1, respectively). The dominant control on net ecosystem exchange (NEE) in the mature bog (between +20 and -54 g C-CO2 m-2 year-1) was soil temperature (5 cm), causing net CO2 loss due to higher ecosystem respiration (ER) in warmer years. In contrast, wetness controlled NEE in the young and intermediate bogs (between +55 and -95 g C-CO2 m-2 year-1), where years with periodic inundation at the beginning of the growing season caused greater reduction in gross primary productivity than in ER leading to CO2 loss. Winter fluxes (November-April) represented 16% of annual ER and 38% of annual CH4 emissions. Our study found NEE of thermokarst bogs to be close to neutral and rules out large CO2 losses under current conditions. However, high CH4 emissions after thaw caused a positive net radiative forcing effect. While wet conditions favouring high CH4 emissions only persist for the initial young bog period, we showed that continued climate warming with increased ER, and thus, CO2 losses from the mature bog can cause net positive radiative forcing which would last for centuries after permafrost thaw.
Collapse
Affiliation(s)
- Liam Heffernan
- Department of Renewable Resources, University of Alberta, Edmonton, Alberta, Canada
| | - Cristian Estop-Aragonés
- Ecohydrology and Biogeochemistry Group, Institute of Landscape Ecology, University of Münster, Münster, Germany
| | - McKenzie A Kuhn
- Department of Earth Sciences and Earth System Research Center, Institute for the Study of Earth, Ocean and Space, University of New Hampshire, Durham, New Hampshire, USA
| | - Klaus Holger-Knorr
- Ecohydrology and Biogeochemistry Group, Institute of Landscape Ecology, University of Münster, Münster, Germany
| | - David Olefeldt
- Department of Renewable Resources, University of Alberta, Edmonton, Alberta, Canada
| |
Collapse
|
2
|
Ustin SL, Middleton EM. Current and Near-Term Earth-Observing Environmental Satellites, Their Missions, Characteristics, Instruments, and Applications. SENSORS (BASEL, SWITZERLAND) 2024; 24:3488. [PMID: 38894281 PMCID: PMC11175343 DOI: 10.3390/s24113488] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2024] [Revised: 05/05/2024] [Accepted: 05/13/2024] [Indexed: 06/21/2024]
Abstract
Among the essential tools to address global environmental information requirements are the Earth-Observing (EO) satellites with free and open data access. This paper reviews those EO satellites from international space programs that already, or will in the next decade or so, provide essential data of importance to the environmental sciences that describe Earth's status. We summarize factors distinguishing those pioneering satellites placed in space over the past half century, and their links to modern ones, and the changing priorities for spaceborne instruments and platforms. We illustrate the broad sweep of instrument technologies useful for observing different aspects of the physio-biological aspects of the Earth's surface, spanning wavelengths from the UV-A at 380 nanometers to microwave and radar out to 1 m. We provide a background on the technical specifications of each mission and its primary instrument(s), the types of data collected, and examples of applications that illustrate these observations. We provide websites for additional mission details of each instrument, the history or context behind their measurements, and additional details about their instrument design, specifications, and measurements.
Collapse
Affiliation(s)
- Susan L. Ustin
- Institute of the Environment, University of California, Davis, Davis, CA 95616, USA
| | | |
Collapse
|
3
|
Gundale MJ, Axelsson EP, Buness V, Callebaut T, DeLuca TH, Hupperts SF, Ibáñez TS, Metcalfe DB, Nilsson MC, Peichl M, Spitzer CM, Stangl ZR, Strengbom J, Sundqvist MK, Wardle DA, Lindahl BD. The biological controls of soil carbon accumulation following wildfire and harvest in boreal forests: A review. GLOBAL CHANGE BIOLOGY 2024; 30:e17276. [PMID: 38683126 DOI: 10.1111/gcb.17276] [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: 02/09/2024] [Revised: 03/29/2024] [Accepted: 03/30/2024] [Indexed: 05/01/2024]
Abstract
Boreal forests are frequently subjected to disturbances, including wildfire and clear-cutting. While these disturbances can cause soil carbon (C) losses, the long-term accumulation dynamics of soil C stocks during subsequent stand development is controlled by biological processes related to the balance of net primary production (NPP) and outputs via heterotrophic respiration and leaching, many of which remain poorly understood. We review the biological processes suggested to influence soil C accumulation in boreal forests. Our review indicates that median C accumulation rates following wildfire and clear-cutting are similar (0.15 and 0.20 Mg ha-1 year-1, respectively), however, variation between studies is extremely high. Further, while many individual studies show linear increases in soil C stocks through time after disturbance, there are indications that C stock recovery is fastest early to mid-succession (e.g. 15-80 years) and then slows as forests mature (e.g. >100 years). We indicate that the rapid build-up of soil C in younger stands appears not only driven by higher plant production, but also by a high rate of mycorrhizal hyphal production, and mycorrhizal suppression of saprotrophs. As stands mature, the balance between reductions in plant and mycorrhizal production, increasing plant litter recalcitrance, and ectomycorrhizal decomposers and saprotrophs have been highlighted as key controls on soil C accumulation rates. While some of these controls appear well understood (e.g. temporal patterns in NPP, changes in aboveground litter quality), many others remain research frontiers. Notably, very little data exists describing and comparing successional patterns of root production, mycorrhizal functional traits, mycorrhizal-saprotroph interactions, or C outputs via heterotrophic respiration and dissolved organic C following different disturbances. We argue that these less frequently described controls require attention, as they will be key not only for understanding ecosystem C balances, but also for representing these dynamics more accurately in soil organic C and Earth system models.
Collapse
Affiliation(s)
- Michael J Gundale
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, Umeå, Sweden
| | - E Petter Axelsson
- Department of Wildlife, Fish and Environmental Studies, Swedish University of Agricultural Sciences, Umeå, Sweden
| | - Vincent Buness
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, Umeå, Sweden
| | - Timon Callebaut
- Department of Environmental Science and Ecology, Umeå University, Umeå, Sweden
| | - Thomas H DeLuca
- College of Forestry, Oregon State University, Corvallis, Oregon, USA
| | - Stefan F Hupperts
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, Umeå, Sweden
| | - Theresa S Ibáñez
- Department of Wildlife, Fish and Environmental Studies, Swedish University of Agricultural Sciences, Umeå, Sweden
| | - Daniel B Metcalfe
- Department of Environmental Science and Ecology, Umeå University, Umeå, Sweden
| | - Marie-Charlotte Nilsson
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, Umeå, Sweden
| | - Matthias Peichl
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, Umeå, Sweden
| | - Clydecia M Spitzer
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, Umeå, Sweden
| | - Zsofia R Stangl
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, Umeå, Sweden
| | - Joachim Strengbom
- Department of Ecology, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Maja K Sundqvist
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, Umeå, Sweden
| | - David A Wardle
- Department of Environmental Science and Ecology, Umeå University, Umeå, Sweden
| | - Björn D Lindahl
- Department of Soil Science, Swedish University of Agricultural Sciences, Uppsala, Sweden
| |
Collapse
|
4
|
Liu Z, Chen B, Wang S, Xu X, Chen H, Liu X, He JS, Wang J, Wang J, Chen J, Wang X, Zheng C, Zhu K, Wang X. More enhanced non-growing season methane exchanges under warming on the Qinghai-Tibetan Plateau. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 917:170438. [PMID: 38286283 DOI: 10.1016/j.scitotenv.2024.170438] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Revised: 01/12/2024] [Accepted: 01/23/2024] [Indexed: 01/31/2024]
Abstract
Uncertainty in methane (CH4) exchanges across wetlands and grasslands in the Qinghai-Tibetan Plateau (QTP) is projected to increase due to continuous permafrost degradation and asymmetrical seasonal warming. Temperature plays a vital role in regulating CH4 exchange, yet the seasonal patterns of temperature dependencies for CH4 fluxes over the wetlands and grasslands on the QTP remain poorly understood. Here, we demonstrated a stronger warming response of CH4 exchanges during the non-growing season compared to the growing season on the QTP. Analyzing 9745 daily observations and employing four methods -regression fitting of temperature-CH4 flux, temperature dependence calculations, field-based and model-based control experiments-we found that warming intensified CH4 emissions in wetlands and uptakes in grasslands. Specifically, the average reaction intensity in the non-growing season surpasses that in the growing season by 1.89 and 4.80 times, respectively. This stronger warming response of CH4 exchanges during the non-growing season significantly increases the regional CH4 exchange on the QTP. Our research reveals that CH4 exchanges in the QTP have a higher warming sensitivity in non-growing seasons, which meanwhile are dominated by a larger warming rate than the annual average. The combined effects of these two factors will significantly alter the CH4 source/sink on the QTP. Neglecting these impacts would lead to inaccurate estimations of CH4 source/sink over the QTP under climate warming.
Collapse
Affiliation(s)
- Zhenhai Liu
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China; Key Laboratory of Coupling Process and Effect of Natural Resources Elements, Beijing, 100055, China
| | - Bin Chen
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; Key Laboratory of Coupling Process and Effect of Natural Resources Elements, Beijing, 100055, China.
| | - Shaoqiang Wang
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China; Hubei Key Laboratory of Regional Ecology and Environmental Change, School of Geography and Information Engineering, China University of Geosciences, Wuhan 430078, China; Technology Innovation Center for Intelligent Monitoring and Spatial Regulation of Land Carbon Sequestrations, Ministry of Natural Resources, Wuhan 430078, China.
| | - Xiyan Xu
- Key Laboratory of Regional Climate-Environment for Temperate East Asia, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China
| | - Huai Chen
- Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization & Ecological Restoration Biodiversity Conservation Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, China; Zoige Peatland and Global Change Research Station, Chinese Academy of Sciences, Hongyuan 624400, China
| | - Xinwei Liu
- Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization & Ecological Restoration Biodiversity Conservation Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, China; Zoige Peatland and Global Change Research Station, Chinese Academy of Sciences, Hongyuan 624400, China
| | - Jin-Sheng He
- State Key Laboratory of Herbage Improvement and Grassland Agro-ecosystems, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou 730000, China; Department of Ecology, College of Urban and Environmental Sciences, and Key Laboratory for Earth Surface Processes of the Ministry of Education, Peking University, Beijing 100871, China
| | - Jianbin Wang
- State Key Laboratory of Herbage Improvement and Grassland Agro-ecosystems, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou 730000, China
| | - Jinsong Wang
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China
| | - Jinghua Chen
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China
| | - Xiaobo Wang
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China
| | - Chen Zheng
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Kai Zhu
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xueqing Wang
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China
| |
Collapse
|
5
|
Zheng Y, Du S, Sun W, Feng C, Su Q. Spatiotemporal patterns of net regional productivity and its causes throughout Ordos, China. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2024; 31:22038-22054. [PMID: 38400969 DOI: 10.1007/s11356-024-32368-0] [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: 10/24/2023] [Accepted: 02/03/2024] [Indexed: 02/26/2024]
Abstract
A comprehensive understanding of the terrestrial carbon sink is essential for proficient regional carbon management. However, previous studies predominantly relied on net ecosystem productivity (NEP) as an indicator of regional carbon sink, overlooking the impacts of carbon emissions from physical processes and carbon leakage associated with anthropogenic activities. In this study, net region productivity (NRP), a vital metric representing carbon sink dynamics in regional multi-landscape ecosystems, was employed to systematically analyze the patterns, trends, and causes of carbon sink in Ordos. The results revealed that spatially averaged NRP in Ordos was 70.334 g·m-2·a-1, indicating a carbon sink effect. The coefficient of variation of NRP was 68.035%, with a higher NRP in the southern region. Normalized difference vegetation index (NDVI) predominantly controlled the spatial heterogeneity of NRP in Ordos, while precipitation emerged as the primary climatic factor influencing spatial differences in NRP. Regional variations in the impact of environmental factors on NRP were evident. In most areas, NRP showed a notable increasing trend influenced by various factors. Specifically, the simultaneous rise in NDVI and improvements in hydrothermal conditions contributed to the gradual elevation of NRP, each with varying degrees of influence across Ordos and its sub-regions.
Collapse
Affiliation(s)
- Yurong Zheng
- College of Geoscience and Surveying Engineering, China University of Mining and Technology (Beijing), Beijing, 100083, China
| | - Shouhang Du
- College of Geoscience and Surveying Engineering, China University of Mining and Technology (Beijing), Beijing, 100083, China.
| | - Wenbin Sun
- College of Geoscience and Surveying Engineering, China University of Mining and Technology (Beijing), Beijing, 100083, China
| | - Cui Feng
- College of Geoscience and Surveying Engineering, China University of Mining and Technology (Beijing), Beijing, 100083, China
| | - Qing Su
- College of Geoscience and Surveying Engineering, China University of Mining and Technology (Beijing), Beijing, 100083, China
| |
Collapse
|
6
|
Glückler R, Gloy J, Dietze E, Herzschuh U, Kruse S. Simulating long-term wildfire impacts on boreal forest structure in Central Yakutia, Siberia, since the Last Glacial Maximum. FIRE ECOLOGY 2024; 20:1. [PMID: 38186675 PMCID: PMC10766680 DOI: 10.1186/s42408-023-00238-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Accepted: 11/30/2023] [Indexed: 01/09/2024]
Abstract
Background Wildfires are recognized as an important ecological component of larch-dominated boreal forests in eastern Siberia. However, long-term fire-vegetation dynamics in this unique environment are poorly understood. Recent paleoecological research suggests that intensifying fire regimes may induce millennial-scale shifts in forest structure and composition. This may, in turn, result in positive feedback on intensifying wildfires and permafrost degradation, apart from threatening human livelihoods. Most common fire-vegetation models do not explicitly include detailed individual-based tree population dynamics, but a focus on patterns of forest structure emerging from interactions among individual trees may provide a beneficial perspective on the impacts of changing fire regimes in eastern Siberia. To simulate these impacts on forest structure at millennial timescales, we apply the individual-based, spatially explicit vegetation model LAVESI-FIRE, expanded with a new fire module. Satellite-based fire observations along with fieldwork data were used to inform the implementation of wildfire occurrence and adjust model parameters. Results Simulations of annual forest development and wildfire activity at a study site in the Republic of Sakha (Yakutia) since the Last Glacial Maximum (c. 20,000 years BP) highlight the variable impacts of fire regimes on forest structure throughout time. Modeled annual fire probability and subsequent burned area in the Holocene compare well with a local reconstruction of charcoal influx in lake sediments. Wildfires can be followed by different forest regeneration pathways, depending on fire frequency and intensity and the pre-fire forest conditions. We find that medium-intensity wildfires at fire return intervals of 50 years or more benefit the dominance of fire-resisting Dahurian larch (Larix gmelinii (Rupr.) Rupr.), while stand-replacing fires tend to enable the establishment of evergreen conifers. Apart from post-fire mortality, wildfires modulate forest development mainly through competition effects and a reduction of the model's litter layer. Conclusion With its fine-scale population dynamics, LAVESI-FIRE can serve as a highly localized, spatially explicit tool to understand the long-term impacts of boreal wildfires on forest structure and to better constrain interpretations of paleoecological reconstructions of fire activity. Supplementary Information The online version contains supplementary material available at 10.1186/s42408-023-00238-8.
Collapse
Affiliation(s)
- Ramesh Glückler
- Polar Terrestrial Environmental Systems, Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Telegrafenberg A45, Potsdam, 14473 Germany
- Institute of Environmental Science and Geography, University of Potsdam, Karl-Liebknecht-Strasse 24-25, Potsdam, 14476 Germany
- Faculty of Environmental Earth Science, Hokkaido University, N10W5, Sapporo, 060-0810 Japan
| | - Josias Gloy
- Polar Terrestrial Environmental Systems, Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Telegrafenberg A45, Potsdam, 14473 Germany
| | - Elisabeth Dietze
- Institute of Geography, Georg-August-University Göttingen, Goldschmidtstrasse 5, Göttingen, 37077 Germany
| | - Ulrike Herzschuh
- Polar Terrestrial Environmental Systems, Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Telegrafenberg A45, Potsdam, 14473 Germany
- Institute of Environmental Science and Geography, University of Potsdam, Karl-Liebknecht-Strasse 24-25, Potsdam, 14476 Germany
- Institute of Biochemistry and Biology, University of Potsdam, Karl-Liebknecht-Strasse 24-25, Potsdam, 14476 Germany
| | - Stefan Kruse
- Polar Terrestrial Environmental Systems, Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Telegrafenberg A45, Potsdam, 14473 Germany
| |
Collapse
|
7
|
Kim JE, Wang JA, Li Y, Czimczik CI, Randerson JT. Wildfire-induced increases in photosynthesis in boreal forest ecosystems of North America. GLOBAL CHANGE BIOLOGY 2024; 30:e17151. [PMID: 38273511 DOI: 10.1111/gcb.17151] [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: 06/28/2023] [Revised: 10/11/2023] [Accepted: 12/12/2023] [Indexed: 01/27/2024]
Abstract
Observations of the annual cycle of atmospheric CO2 in high northern latitudes provide evidence for an increase in terrestrial metabolism in Arctic tundra and boreal forest ecosystems. However, the mechanisms driving these changes are not yet fully understood. One proposed hypothesis is that ecological change from disturbance, such as wildfire, could increase the magnitude and change the phase of net ecosystem exchange through shifts in plant community composition. Yet, little quantitative work has evaluated this potential mechanism at a regional scale. Here we investigate how fire disturbance influences landscape-level patterns of photosynthesis across western boreal North America. We use Alaska and Canadian large fire databases to identify the perimeters of wildfires, a Landsat-derived land cover time series to characterize plant functional types (PFTs), and solar-induced fluorescence (SIF) from the Orbiting Carbon Observatory-2 (OCO-2) as a proxy for photosynthesis. We analyze these datasets to characterize post-fire changes in plant succession and photosynthetic activity using a space-for-time approach. We find that increases in herbaceous and sparse vegetation, shrub, and deciduous broadleaf forest PFTs during mid-succession yield enhancements in SIF by 8-40% during June and July for 2- to 59-year stands relative to pre-fire controls. From the analysis of post-fire land cover changes within individual ecoregions and modeling, we identify two mechanisms by which fires contribute to long-term trends in SIF. First, increases in annual burning are shifting the stand age distribution, leading to increases in the abundance of shrubs and deciduous broadleaf forests that have considerably higher SIF during early- and mid-summer. Second, fire appears to facilitate a long-term shift from evergreen conifer to broadleaf deciduous forest in the Boreal Plain ecoregion. These findings suggest that increasing fire can contribute substantially to positive trends in seasonal CO2 exchange without a close coupling to long-term increases in carbon storage.
Collapse
Affiliation(s)
- Jinhyuk E Kim
- Department of Earth System Science, University of California, Irvine, California, USA
| | - Jonathan A Wang
- School of Biological Sciences, University of Utah, Salt Lake City, Utah, USA
| | - Yue Li
- Department of Geography, University of California, Los Angeles, California, USA
| | - Claudia I Czimczik
- Department of Earth System Science, University of California, Irvine, California, USA
| | - James T Randerson
- Department of Earth System Science, University of California, Irvine, California, USA
| |
Collapse
|
8
|
Euskirchen ES, Edgar CW, Kane ES, Waldrop MP, Neumann RB, Manies KL, Douglas TA, Dieleman C, Jones MC, Turetsky MR. Persistent net release of carbon dioxide and methane from an Alaskan lowland boreal peatland complex. GLOBAL CHANGE BIOLOGY 2024; 30:e17139. [PMID: 38273498 DOI: 10.1111/gcb.17139] [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: 07/13/2023] [Revised: 11/20/2023] [Accepted: 12/18/2023] [Indexed: 01/27/2024]
Abstract
Permafrost degradation in peatlands is altering vegetation and soil properties and impacting net carbon storage. We studied four adjacent sites in Alaska with varied permafrost regimes, including a black spruce forest on a peat plateau with permafrost, two collapse scar bogs of different ages formed following thermokarst, and a rich fen without permafrost. Measurements included year-round eddy covariance estimates of net carbon dioxide (CO2 ), mid-April to October methane (CH4 ) emissions, and environmental variables. From 2011 to 2022, annual rainfall was above the historical average, snow water equivalent increased, and snow-season duration shortened due to later snow return. Seasonally thawed active layer depths also increased. During this period, all ecosystems acted as slight annual sources of CO2 (13-59 g C m-2 year-1 ) and stronger sources of CH4 (11-14 g CH4 m-2 from ~April to October). The interannual variability of net ecosystem exchange was high, approximately ±100 g C m-2 year-1 , or twice what has been previously reported across other boreal sites. Net CO2 release was positively related to increased summer rainfall and winter snow water equivalent and later snow return. Controls over CH4 emissions were related to increased soil moisture and inundation status. The dominant emitter of carbon was the rich fen, which, in addition to being a source of CO2 , was also the largest CH4 emitter. These results suggest that the future carbon-source strength of boreal lowlands in Interior Alaska may be determined by the area occupied by minerotrophic fens, which are expected to become more abundant as permafrost thaw increases hydrologic connectivity. Since our measurements occur within close proximity of each other (≤1 km2 ), this study also has implications for the spatial scale and data used in benchmarking carbon cycle models and emphasizes the necessity of long-term measurements to identify carbon cycle process changes in a warming climate.
Collapse
Affiliation(s)
- Eugénie S Euskirchen
- Institute of Arctic Biology, University of Alaska Fairbanks, Fairbanks, Alaska, USA
- Department of Biology and Wildlife, University of Alaska Fairbanks, Fairbanks, Alaska, USA
| | - Colin W Edgar
- Institute of Arctic Biology, University of Alaska Fairbanks, Fairbanks, Alaska, USA
| | - Evan S Kane
- College of Forest Resources and Environmental Science, Michigan Technological University, Houghton, Michigan, USA
- Northern Research Station, USDA Forest Service, Houghton, Michigan, USA
| | - Mark P Waldrop
- U.S. Geological Survey, Geology, Minerals, Energy, and Geophysics Science Center, Moffett Fields, Mountain View, California, USA
| | - Rebecca B Neumann
- Department of Civil and Environmental Engineering, University of Washington, Seattle, Washington, USA
| | - Kristen L Manies
- U.S. Geological Survey, Geology, Minerals, Energy, and Geophysics Science Center, Moffett Fields, Mountain View, California, USA
| | - Thomas A Douglas
- U.S. Army Cold Regions Research & Engineering Laboratory, Fort Wainwright, Fairbanks, Alaska, USA
| | - Catherine Dieleman
- Department of Integrative Biology, University of Guelph, Guelph, Ontario, Canada
| | - Miriam C Jones
- U.S. Geological Survey, Florence Bascom Geoscience Center, Reston, Virginia, USA
| | - Merritt R Turetsky
- Institute of Arctic and Alpine Research, Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, Colorado, USA
| |
Collapse
|
9
|
Li W, Manzanedo RD, Jiang Y, Ma W, Du E, Zhao S, Rademacher T, Dong M, Xu H, Kang X, Wang J, Wu F, Cui X, Pederson N. Reassessment of growth-climate relations indicates the potential for decline across Eurasian boreal larch forests. Nat Commun 2023; 14:3358. [PMID: 37291110 PMCID: PMC10250375 DOI: 10.1038/s41467-023-39057-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Accepted: 05/23/2023] [Indexed: 06/10/2023] Open
Abstract
Larch, a widely distributed tree in boreal Eurasia, is experiencing rapid warming across much of its distribution. A comprehensive assessment of growth on warming is needed to comprehend the potential impact of climate change. Most studies, relying on rigid calendar-based temperature series, have detected monotonic responses at the margins of boreal Eurasia, but not across the region. Here, we developed a method for constructing temporally flexible and physiologically relevant temperature series to reassess growth-temperature relations of larch across boreal Eurasia. Our method appears more effective in assessing the impact of warming on growth than previous methods. Our approach indicates widespread and spatially heterogeneous growth-temperature responses that are driven by local climate. Models quantifying these results project that the negative responses of growth to temperature will spread northward and upward throughout this century. If true, the risks of warming to boreal Eurasia could be more widespread than conveyed from previous works.
Collapse
Affiliation(s)
- Wenqing Li
- Beijing Key Laboratory of Traditional Chinese Medicine Protection and Utilization, Faculty of Geographical Science, Beijing Normal University, Beijing 100875, Zhuhai, 519087, China
- Key Laboratory of Land Consolidation and Rehabilitation, Land Consolidation and Rehabilitation Center, Ministry of Natural Resources, Beijing, 100035, China
| | - Rubén D Manzanedo
- Harvard Forest, Harvard University, Petersham, MA, 01366, USA
- Plant Ecology, Institute of Integrative Biology, D-USYS, ETH Zürich, 8006, Zürich, Switzerland
| | - Yuan Jiang
- Beijing Key Laboratory of Traditional Chinese Medicine Protection and Utilization, Faculty of Geographical Science, Beijing Normal University, Beijing 100875, Zhuhai, 519087, China.
- State Key Laboratory of Earth Surface Processes and Resource Ecology, Faculty of Geographical Science, Beijing Normal University, Beijing, 100875, China.
| | - Wenqiu Ma
- College of Engineering, China Agricultural University, Beijing, 100083, China
| | - Enzai Du
- State Key Laboratory of Earth Surface Processes and Resource Ecology, Faculty of Geographical Science, Beijing Normal University, Beijing, 100875, China
| | - Shoudong Zhao
- State Key Laboratory of Severe Weather, Chinese Academy of Meteorological Sciences, Beijing, 100081, China
| | - Tim Rademacher
- Harvard Forest, Harvard University, Petersham, MA, 01366, USA
- Institut des Sciences de la Forêt Tempérée, Université du Québec en Outaouais, Ripon, J0V 1V0, QC, Canada
| | - Manyu Dong
- Beijing Key Laboratory of Traditional Chinese Medicine Protection and Utilization, Faculty of Geographical Science, Beijing Normal University, Beijing 100875, Zhuhai, 519087, China
- State Key Laboratory of Earth Surface Processes and Resource Ecology, Faculty of Geographical Science, Beijing Normal University, Beijing, 100875, China
| | - Hui Xu
- Department of Biostatistics and Epidemiology, School of Public Health and Health Sciences, University of Massachusetts Amherst, Amherst, MA, 01003, USA
| | - Xinyu Kang
- Department of Mathematics and Statistics, Boston University, 111 Cummington Mall, Boston, MA, 02215, USA
| | - Jun Wang
- Key Laboratory of Land Consolidation and Rehabilitation, Land Consolidation and Rehabilitation Center, Ministry of Natural Resources, Beijing, 100035, China
| | - Fang Wu
- Beijing Key Laboratory of Traditional Chinese Medicine Protection and Utilization, Faculty of Geographical Science, Beijing Normal University, Beijing 100875, Zhuhai, 519087, China
- School of Systems Science, Beijing Normal University, Beijing, 100875, China
| | - Xuefeng Cui
- School of Systems Science, Beijing Normal University, Beijing, 100875, China
| | - Neil Pederson
- Harvard Forest, Harvard University, Petersham, MA, 01366, USA
| |
Collapse
|