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Zhao R, Shang Y, Jacinthe PA, Li S, Liu G, Wen Z, Wang Z, Yang Q, Fang C, Song K. Variations in surface area and biogeochemistry of subarctic-arctic lakes established through satellite and in-situ observations: An overview of published research from the past 30 years. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 931:172797. [PMID: 38679084 DOI: 10.1016/j.scitotenv.2024.172797] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2023] [Revised: 04/03/2024] [Accepted: 04/24/2024] [Indexed: 05/01/2024]
Abstract
Human activities have strongly impacted the global climate, and during the last few decades the global average temperature has risen at a rate faster than at any time on record. High latitude lakes in the subarctic and arctic permafrost regions have particularly been vulnerable given the "Arctic amplification" phenomenon and acceleration in warming rate in the northern hemisphere (0.2-0.8 °C/decade). This paper presents a comprehensive overview of the last 30 years of research investigating how subarctic and Arctic lakes respond to climate warming. The review focused on studies where remote sensing technology was used to quantify these responses. The difference between summer lake water temperature and air temperature varied between 1.7 and 5.4 °C in subarctic lakes and 2.4-3.2 °C in Arctic lakes. Overall, the freezing date of lake ice is generally delayed and the date of lake thawing occurs earlier. Lake surface area (4-48.5 %), and abundance in the subarctic and Arctic region have increased significantly due to rising temperature, permafrost thawing, increased precipitation and other localized surface disturbances. However, in recent years, instances of lake shrinkage (between -0.4 % and -40 %) have also been reported, likely due to riparian overflow, groundwater infiltration and lateral drainage. Furthermore, in subarctic and Arctic lakes, climate change and permafrost thawing would release CO2 and CH4, and alter carbon dynamics in impacted lakes through various interconnected processes which could potentially affect the quality of carbon (terrestrial, algae) entering a lake system. The review also highlighted a potential intersection between permafrost melting and public health through human exposure to long-buried viruses. Subarctic and arctic ecosystems' responses to climate change will continue to be an area of intense research interest, and this review has highlighted priority areas for research and how remote sensing technologies can facilitate the pursuit of such a research agenda.
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Affiliation(s)
- Ruixue Zhao
- Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, China; School of Geomatics and Prospecting Engineering, Jilin Jianzhu University, Changchun 130118, China
| | - Yingxin Shang
- Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, China
| | - Pierre-André Jacinthe
- Department of Earth Sciences, Indiana University-Purdue University, Indianapolis, IN 46202, USA
| | - Sijia Li
- Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, China
| | - Ge Liu
- Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, China
| | - Zhidan Wen
- Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, China
| | - Zijin Wang
- Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, China
| | - Qian Yang
- Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, China
| | - Chong Fang
- Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, China
| | - Kaishan Song
- Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, China; School of Environment and Planning, Liaocheng University, Liaocheng 252000, China.
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Speetjens NJ, Berghuijs WR, Wagner J, Vonk JE. Degradation of ice-wedge polygons leads to increased fluxes of water and DOC. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 920:170931. [PMID: 38360315 DOI: 10.1016/j.scitotenv.2024.170931] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2023] [Revised: 01/29/2024] [Accepted: 02/10/2024] [Indexed: 02/17/2024]
Abstract
Ice-wedge polygon landscapes make up a substantial part of high-latitude permafrost landscapes. The hydrological conditions shape how these landscapes store and release organic carbon. However, their coupled water‑carbon dynamics are poorly understood as field measurements are sparse in smaller catchments and coupled hydrology-dissolved organic carbon (DOC) models are not tailored for these landscapes. Here we present a model that simulates the hydrology and associated DOC export of high-centered and low-centered ice-wedge polygons and apply the model to a small catchment with abundant polygon coverage along the Yukon Coast, Canada. The modeled seasonal pattern of water and carbon fluxes aligns with sparse field data. These modeled seasonal patterns indicate that early-season runoff is mostly surficial and generated by low-centered polygons and snow trapped in troughs of high-centered polygons. High-centered polygons show potential for deeper subsurface flow under future climate conditions. This suggests that high-centered polygons will be responsible for an increasing proportion of annual DOC export compared to low-centered polygons. Warming likely shifts low-centered polygons to high-centered polygons, and our model shows that this shift will cause a deepening of the active layer and a lengthening of the thawing season. This, in turn, intensifies seasonal runoff and DOC flux, mainly through its duration. Our model provides a physical hypothesis that can be used to further quantify and refine our understanding of hydrology and DOC export of arctic ice-wedge polygon terrain.
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Affiliation(s)
- Niek Jesse Speetjens
- Department of Earth Sciences, Vrije Universiteit Amsterdam, 1081 HV Amsterdam, the Netherlands; School of Environmental Studies (ENVI), University of Victoria, V8W 2Y2 Victoria, BC, Canada.
| | - Wouter R Berghuijs
- Department of Earth Sciences, Vrije Universiteit Amsterdam, 1081 HV Amsterdam, the Netherlands
| | - Julia Wagner
- Department of Physical Geography, Stockholm University (SU), 106 91 Stockholm, Sweden
| | - Jorien E Vonk
- Department of Earth Sciences, Vrije Universiteit Amsterdam, 1081 HV Amsterdam, the Netherlands
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Ren Z, Zhang C, Li X, Luo W. Thermokarst lakes are hotspots of antibiotic resistance genes in permafrost regions on the Qinghai-Tibet Plateau. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2024; 344:123334. [PMID: 38218544 DOI: 10.1016/j.envpol.2024.123334] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Revised: 11/02/2023] [Accepted: 01/07/2024] [Indexed: 01/15/2024]
Abstract
Antibiotic resistance genes (ARGs) are natural products and emerging pollutants in remote environments, including permafrost regions that are rapidly thawing due to climate warming. We investigated the role of thermokarst lakes (including sediment and water) in reserving ARGs compared to permafrost soils across the permafrost regions on the Qinghai-Tibet Plateau. As intrinsically connected distinct environments, permafrost soil, lake sediment, and lake water harbored 1239 ARGs in total, while a considerable number of same ARGs (683 out of 1239) concurrently presented in all these environments. Soil and sediment had a higher number of ARGs than water. Multidrug resistance genes were the most diverse and abundant in all three environments, where cls, ropB, mdfA, fabI, and macB were the top five most abundant ARGs while with different orders. Soil and sediment had similar ARG profiles, and the alpha and beta diversity of ARGs in sediment were positively correlated with that in soil. The beta diversity of ARG profiles between sediment and soil was highly contributed by turnover component (89%). However, turnover and nestedness components were almost equality contributed (46%-54%) to the beta diversity of ARG profiles between soil and water as well as between sediment and water. The results suggested that thermokarst lake sediments might inherit the ARGs in permafrost soils. Water ARGs are the subset of soil ARGs and sediment ARGs to a certain degree with species turnover playing a significant role. When accounting the ARGs in sediment and water together, thermokarst lakes had a significantly higher number of ARGs than permafrost soils, suggesting that thermokarst lakes act as the hotspots of ARGs in permafrost regions. These findings are disturbing especially due to the fact that tremendous number of thermokarst lakes are forming under accelerating climate change.
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Affiliation(s)
- Ze Ren
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, 210008, China
| | - Cheng Zhang
- Advanced Institute of Natural Sciences, Beijing Normal University, Zhuhai, 519087, China; School of Engineering Technology, Beijing Normal University, Zhuhai, 519087, China
| | - Xia Li
- Advanced Institute of Natural Sciences, Beijing Normal University, Zhuhai, 519087, China
| | - Wei Luo
- Key Laboratory for Polar Science, Polar Research Institute of China, Ministry of Natural Resources, Shanghai, 200136, China; Key Laboratory of Polar Ecosystem and Climate Change (Shanghai Jiao Tong University), Ministry of Education, Shanghai, 200030, China; The Technology and Equipment Engineering Centre for Polar Observations, Zhejiang University, Zhoushan, 316000, China.
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Liu Y, Qiu H, Kamp U, Wang N, Wang J, Huang C, Tang B. Higher temperature sensitivity of retrogressive thaw slump activity in the Arctic compared to the Third Pole. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 914:170007. [PMID: 38219993 DOI: 10.1016/j.scitotenv.2024.170007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Revised: 01/02/2024] [Accepted: 01/06/2024] [Indexed: 01/16/2024]
Abstract
Climate change exacerbates permafrost thawing, resulting exceptionally intense retrogressive thaw slump (RTS) activity in the Arctic and Third Pole. However, comparative assessments of permafrost characteristics and RTS sensitivity under warming climate at both poles are still lacking. Here, the severity and temperature sensitivity of RTS were presented and compared using Tasselled Cap (TC) trend analysis of time-series Landsat images and Interferometric Synthetic Aperture Radar (InSAR) measurement. RTS has a more severe growth trend in the Arctic cold permafrost region, also with a deformation rate of approximately 70 mm/year and cumulative displacement up to 120 mm. In comparison, the deformation rate in the Third Pole is approximately 50 mm/year. The RTS severity in the Arctic is about 1.5 times higher than in the Third Pole, primarily owing to different sensitivities of cold and warm permafrost under warming climate. The intensification and vulnerability of RTS have global implications on climatological processes, hydrology, carbon release and ground stability, thus calling for attention and effective governance action.
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Affiliation(s)
- Ya Liu
- Shaanxi Key Laboratory of Earth Surface and Environmental Carrying Capacity, College of Urban and Environmental Sciences, Northwest University, Xi'an 710127, China
| | - Haijun Qiu
- Shaanxi Key Laboratory of Earth Surface and Environmental Carrying Capacity, College of Urban and Environmental Sciences, Northwest University, Xi'an 710127, China; Insitute of Earth Surface System and Hazards, College of Urban and Environmental Sciences, Northwest University, Xi'an 710127, China.
| | - Ulrich Kamp
- Earth and Environmental Sciences Discipline, Department of Natural Sciences, University of Michigan-Dearborn, Dearborn, MI 4, USA
| | - Ninglian Wang
- Shaanxi Key Laboratory of Earth Surface and Environmental Carrying Capacity, College of Urban and Environmental Sciences, Northwest University, Xi'an 710127, China; Insitute of Earth Surface System and Hazards, College of Urban and Environmental Sciences, Northwest University, Xi'an 710127, China
| | - Jiading Wang
- State Key Laboratory of Continental Dynamics, Department of Geology, Northwest University, Xi'an 710069, China
| | - Chang Huang
- Shaanxi Key Laboratory of Earth Surface and Environmental Carrying Capacity, College of Urban and Environmental Sciences, Northwest University, Xi'an 710127, China; Insitute of Earth Surface System and Hazards, College of Urban and Environmental Sciences, Northwest University, Xi'an 710127, China
| | - Bingzhe Tang
- Shaanxi Key Laboratory of Earth Surface and Environmental Carrying Capacity, College of Urban and Environmental Sciences, Northwest University, Xi'an 710127, China; Insitute of Earth Surface System and Hazards, College of Urban and Environmental Sciences, Northwest University, Xi'an 710127, China
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5
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Yang S, Wen X, Wagner D, Strauss J, Kallmeyer J, Anthony SE, Liebner S. Microbial assemblages in Arctic coastal thermokarst lakes and lagoons. FEMS Microbiol Ecol 2024; 100:fiae014. [PMID: 38308515 PMCID: PMC10883142 DOI: 10.1093/femsec/fiae014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2023] [Revised: 11/22/2023] [Accepted: 02/01/2024] [Indexed: 02/04/2024] Open
Abstract
Several studies have investigated changes in microbial community composition in thawing permafrost landscapes, but microbial assemblages in the transient ecosystems of the Arctic coastline remain poorly understood. Thermokarst lakes, abrupt permafrost thaw features, are widespread along the pan-Arctic coast and transform into thermokarst lagoons upon coastal erosion and sea-level rise. This study looks at the effect of marine water inundation (imposing a sulfate-rich, saline environment on top of former thermokarst lake sediments) on microbial community composition and the processes potentially driving microbial community assembly. In the uppermost lagoon sediment influenced from marine water inflow, the microbial structures were significantly different from those deeper in the lagoon sediment and from those of the lakes. In addition, they became more similar along depth compared with lake communities. At the same time, the diversity of core microbial consortia community decreased compared with the lake sediments. This work provides initial observational evidence that Arctic thermokarst lake to lagoon transitions do not only substantially alter microbial communities but also that this transition has a larger effect than permafrost thaw and lake formation history.
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Affiliation(s)
- Sizhong Yang
- GFZ German Research Centre for Geosciences, Helmholtz Centre Potsdam, Section Geomicrobiology, Telegrafenberg, Potsdam, Germany
- Cyrosphere Research Station on the Qinghai-Tibet Plateau, State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Donggang West Road 320, Lanzhou 730000, China
| | - Xi Wen
- College of Electrical Engineering, Northwest Minzu University, Xibei Xincun 1, Lanzhou 730070, China
| | - Dirk Wagner
- GFZ German Research Centre for Geosciences, Helmholtz Centre Potsdam, Section Geomicrobiology, Telegrafenberg, Potsdam, Germany
- Institute of Geosciences, University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476 Potsdam, Germany
| | - Jens Strauss
- Permafrost Research Section, Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Telegrafenberg, Potsdam, Germany
| | - Jens Kallmeyer
- GFZ German Research Centre for Geosciences, Helmholtz Centre Potsdam, Section Geomicrobiology, Telegrafenberg, Potsdam, Germany
| | - Sara E Anthony
- Institute of Geology and Mineralogy, University of Cologne, Zülpicher Str. 49a, 50674 Cologne, Germany
| | - Susanne Liebner
- GFZ German Research Centre for Geosciences, Helmholtz Centre Potsdam, Section Geomicrobiology, Telegrafenberg, Potsdam, Germany
- University of Potsdam, Institute of Biochemistry and Biology, Karl-Liebknecht-Str. 24-25, 14476 Potsdam, Germany
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Seppey CVW, Cabrol L, Thalasso F, Gandois L, Lavergne C, Martinez-Cruz K, Sepulveda-Jauregui A, Aguilar-Muñoz P, Astorga-España MS, Chamy R, Dellagnezze BM, Etchebehere C, Fochesatto GJ, Gerardo-Nieto O, Mansilla A, Murray A, Sweetlove M, Tananaev N, Teisserenc R, Tveit AT, Van de Putte A, Svenning MM, Barret M. Biogeography of microbial communities in high-latitude ecosystems: Contrasting drivers for methanogens, methanotrophs and global prokaryotes. Environ Microbiol 2023; 25:3364-3386. [PMID: 37897125 DOI: 10.1111/1462-2920.16526] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2023] [Accepted: 10/02/2023] [Indexed: 10/29/2023]
Abstract
Methane-cycling is becoming more important in high-latitude ecosystems as global warming makes permafrost organic carbon increasingly available. We explored 387 samples from three high-latitudes regions (Siberia, Alaska and Patagonia) focusing on mineral/organic soils (wetlands, peatlands, forest), lake/pond sediment and water. Physicochemical, climatic and geographic variables were integrated with 16S rDNA amplicon sequences to determine the structure of the overall microbial communities and of specific methanogenic and methanotrophic guilds. Physicochemistry (especially pH) explained the largest proportion of variation in guild composition, confirming species sorting (i.e., environmental filtering) as a key mechanism in microbial assembly. Geographic distance impacted more strongly beta diversity for (i) methanogens and methanotrophs than the overall prokaryotes and, (ii) the sediment habitat, suggesting that dispersal limitation contributed to shape the communities of methane-cycling microorganisms. Bioindicator taxa characterising different ecological niches (i.e., specific combinations of geographic, climatic and physicochemical variables) were identified, highlighting the importance of Methanoregula as generalist methanogens. Methylocystis and Methylocapsa were key methanotrophs in low pH niches while Methylobacter and Methylomonadaceae in neutral environments. This work gives insight into the present and projected distribution of methane-cycling microbes at high latitudes under climate change predictions, which is crucial for constraining their impact on greenhouse gas budgets.
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Affiliation(s)
- Christophe V W Seppey
- Department of Arctic and Marine Biology, UiT The Arctic University of Norway, Tromsø, Norway
- Institute of Environmental Science and Geography, University of Potsdam, Potsdam-Golm, Germany
| | - Léa Cabrol
- Aix-Marseille University, CNRS, IRD, Mediterranean Institute of Oceanography (MIO) UM 110, Marseille, France
- Millennium Institute Biodiversity of Antarctic and Subantarctic Ecosystems (BASE), Santiago, Chile
| | - Frederic Thalasso
- Centro de Investigacíon y de Estudios Avanzados del Instituto Politecnico Nacional (Cinvestav-IPN), Departamento de Biotecnología y Bioingeniería, México, Mexico
| | - Laure Gandois
- Laboratoire Écologie Fonctionnelle et Environnement, Université de Toulouse, CNRS, Toulouse, France
| | - Céline Lavergne
- HUB AMBIENTAL UPLA, Laboratory of Aquatic Environmental Research, Universidad de Playa Ancha, Valparaíso, Chile
- Escuela de Ingeniería Bioquímica, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile
| | - Karla Martinez-Cruz
- Departamento de Ciencias y Recursos Naturales, Universidad de Magallanes, Punta Arenas, Chile
- Environmental Physics Group, Limnological Institute, University of Konstanz, Konstanz, Germany
| | | | - Polette Aguilar-Muñoz
- HUB AMBIENTAL UPLA, Laboratory of Aquatic Environmental Research, Universidad de Playa Ancha, Valparaíso, Chile
- Escuela de Ingeniería Bioquímica, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile
| | | | - Rolando Chamy
- Escuela de Ingeniería Bioquímica, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile
| | - Bruna Martins Dellagnezze
- Microbial Ecology Laboratory, Department of Microbial Biochemistry and Genomic, Biological Research Institute "Clemente Estable", Montevideo, Uruguay
| | - Claudia Etchebehere
- Microbial Ecology Laboratory, Department of Microbial Biochemistry and Genomic, Biological Research Institute "Clemente Estable", Montevideo, Uruguay
| | - Gilberto J Fochesatto
- Department of Atmospheric Sciences, University of Alaska Fairbanks, Fairbanks, Alaska, USA
| | - Oscar Gerardo-Nieto
- Centro de Investigacíon y de Estudios Avanzados del Instituto Politecnico Nacional (Cinvestav-IPN), Departamento de Biotecnología y Bioingeniería, México, Mexico
| | - Andrés Mansilla
- Departamento de Ciencias y Recursos Naturales, Universidad de Magallanes, Punta Arenas, Chile
| | - Alison Murray
- Division of Earth and Ecosystem Sciences, Desert Research Institute, Reno, Nevada, USA
| | - Maxime Sweetlove
- Royal Belgian Institute for Natural Sciences, OD-Nature, Brussels, Belgium
| | - Nikita Tananaev
- Melnikov Permafrost Institute, Russian Academy of Sciences, Yakutsk, Russia
- Institute of Natural Sciences, North-Eastern Federal University, Yakutsk, Russia
| | - Roman Teisserenc
- Laboratoire Écologie Fonctionnelle et Environnement, Université de Toulouse, CNRS, Toulouse, France
| | - Alexander T Tveit
- Department of Arctic and Marine Biology, UiT The Arctic University of Norway, Tromsø, Norway
| | - Anton Van de Putte
- Royal Belgian Institute for Natural Sciences, OD-Nature, Brussels, Belgium
| | - Mette M Svenning
- Department of Arctic and Marine Biology, UiT The Arctic University of Norway, Tromsø, Norway
| | - Maialen Barret
- Laboratoire Écologie Fonctionnelle et Environnement, Université de Toulouse, CNRS, Toulouse, France
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Wang R, Guo L, Yang Y, Zheng H, Jia H, Diao B, Li H, Liu J. Thermokarst lake susceptibility assessment using machine learning models in permafrost landscapes of the Arctic. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 900:165709. [PMID: 37516190 DOI: 10.1016/j.scitotenv.2023.165709] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2023] [Revised: 07/02/2023] [Accepted: 07/20/2023] [Indexed: 07/31/2023]
Abstract
Ice-rich permafrost thaws in response to rapid Arctic warming, and ground subsidence facilitates the formation of thermokarst lakes. Thermokarst lakes transform the surface energy balance of permafrost, affecting geomorphology, hydrology, ecology, and infrastructure stability, which can further contribute to greenhouse gas emissions. Currently, the spatial distribution of thermokarst lakes at large scales remains a challenging task. Based on multiple high-resolution environmental factors and thermokarst lake inventories, we used machine learning methods to estimate the spatial distributions of present and future thermokarst lake susceptibility (TLS) maps. We also identified key environmental factors of the TLS map. At 1.8 × 106 km2, high and very high susceptible regions were estimated to cover about 10.4 % of the region poleward of 60°N, which were mainly distributed in permafrost-dominated lowland regions. At least 23.9 % of the area of TLS maps was projected to disappear under representative concentration pathway scenarios (RCPs), with increased susceptibility levels in northern Canada. The slope was the key conditioning factor for the occurrence of thermokarst lakes in Arctic permafrost regions. Compared with similar studies, the reliability of the TLS map was further evaluated using probability calibration curve and coefficient of variation (CV). Our results provide a means for assessing the spatial distribution of thermokarst lakes at the circum-Arctic scale but also improve the understanding of their dynamics in response to the climate system.
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Affiliation(s)
- Rui Wang
- Key Laboratory of Environmental Change and Natural Disasters, Ministry of Education, Beijing Normal University, Beijing 100875, China; State Key Laboratory of Earth Surface Processes and Resource Ecology (ESPRE), Beijing Normal University, Beijing, 100875, China; Faculty of Geographical Science, Beijing Normal University, Beijing 100875, China
| | - Lanlan Guo
- Key Laboratory of Environmental Change and Natural Disasters, Ministry of Education, Beijing Normal University, Beijing 100875, China; State Key Laboratory of Earth Surface Processes and Resource Ecology (ESPRE), Beijing Normal University, Beijing, 100875, China; Faculty of Geographical Science, Beijing Normal University, Beijing 100875, China
| | - Yuting Yang
- Faculty of Geomatics, Lanzhou Jiaotong University, Lanzhou 730070, China
| | - Hao Zheng
- Key Laboratory of Environmental Change and Natural Disasters, Ministry of Education, Beijing Normal University, Beijing 100875, China; State Key Laboratory of Earth Surface Processes and Resource Ecology (ESPRE), Beijing Normal University, Beijing, 100875, China; Faculty of Geographical Science, Beijing Normal University, Beijing 100875, China
| | - Hong Jia
- Key Laboratory of Environmental Change and Natural Disasters, Ministry of Education, Beijing Normal University, Beijing 100875, China; State Key Laboratory of Earth Surface Processes and Resource Ecology (ESPRE), Beijing Normal University, Beijing, 100875, China; Faculty of Geographical Science, Beijing Normal University, Beijing 100875, China
| | - Baijian Diao
- Key Laboratory of Environmental Change and Natural Disasters, Ministry of Education, Beijing Normal University, Beijing 100875, China; State Key Laboratory of Earth Surface Processes and Resource Ecology (ESPRE), Beijing Normal University, Beijing, 100875, China; Faculty of Geographical Science, Beijing Normal University, Beijing 100875, China
| | - Hang Li
- Key Laboratory of Environmental Change and Natural Disasters, Ministry of Education, Beijing Normal University, Beijing 100875, China; State Key Laboratory of Earth Surface Processes and Resource Ecology (ESPRE), Beijing Normal University, Beijing, 100875, China; Faculty of Geographical Science, Beijing Normal University, Beijing 100875, China
| | - Jifu Liu
- Key Laboratory of Environmental Change and Natural Disasters, Ministry of Education, Beijing Normal University, Beijing 100875, China; State Key Laboratory of Earth Surface Processes and Resource Ecology (ESPRE), Beijing Normal University, Beijing, 100875, China; Faculty of Geographical Science, Beijing Normal University, Beijing 100875, China.
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8
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Chen Y, Cheng X, Liu A, Chen Q, Wang C. Tracking lake drainage events and drained lake basin vegetation dynamics across the Arctic. Nat Commun 2023; 14:7359. [PMID: 37968270 PMCID: PMC10652023 DOI: 10.1038/s41467-023-43207-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Accepted: 11/03/2023] [Indexed: 11/17/2023] Open
Abstract
Widespread lake drainage can lead to large-scale drying in Arctic lake-rich areas, affecting hydrology, ecosystems and permafrost carbon dynamics. To date, the spatio-temporal distribution, driving factors, and post-drainage dynamics of lake drainage events across the Arctic remain unclear. Using satellite remote sensing and surface water products, we identify over 35,000 (~0.6% of all lakes) lake drainage events in the northern permafrost zone between 1984 and 2020, with approximately half being relatively understudied non-thermokarst lakes. Smaller, thermokarst, and discontinuous permafrost area lakes are more susceptible to drainage compared to their larger, non-thermokarst, and continuous permafrost area counterparts. Over time, discontinuous permafrost areas contribute more drained lakes annually than continuous permafrost areas. Following drainage, vegetation rapidly colonizes drained lake basins, with thermokarst drained lake basins showing significantly higher vegetation growth rates and greenness levels than their non-thermokarst counterparts. Under warming, drained lake basins are likely to become more prevalent and serve as greening hotspots, playing an important role in shaping Arctic ecosystems.
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Affiliation(s)
- Yating Chen
- College of Geography and Environment, Shandong Normal University, Jinan, 250014, China.
- Key Laboratory of Comprehensive Observation of Polar Environment (Sun Yat-sen University), Ministry of Education, Zhuhai, 519082, China.
- College of Global Change and Earth System Science, Beijing Normal University, 100875, Beijing, China.
| | - Xiao Cheng
- Key Laboratory of Comprehensive Observation of Polar Environment (Sun Yat-sen University), Ministry of Education, Zhuhai, 519082, China.
- School of Geospatial Engineering and Science, Sun Yat-sen University, and Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, 519082, China.
| | - Aobo Liu
- College of Geography and Environment, Shandong Normal University, Jinan, 250014, China.
- Key Laboratory of Comprehensive Observation of Polar Environment (Sun Yat-sen University), Ministry of Education, Zhuhai, 519082, China.
- College of Global Change and Earth System Science, Beijing Normal University, 100875, Beijing, China.
| | - Qingfeng Chen
- College of Geography and Environment, Shandong Normal University, Jinan, 250014, China
| | - Chengxin Wang
- College of Geography and Environment, Shandong Normal University, Jinan, 250014, China
- Key Research Institute of Yellow River Civilization and Sustainable Development & Yellow River Civilization by Provincial and Ministerial Co-construction of Collaborative Innovation Center, Henan University, Kaifeng, 475001, China
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Wang T, Kalalian C, Fillion D, Perrier S, Chen J, Domine F, Zhang L, George C. Sunlight Induces the Production of Atmospheric Volatile Organic Compounds (VOCs) from Thermokarst Ponds. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:17363-17373. [PMID: 37903215 DOI: 10.1021/acs.est.3c03303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/01/2023]
Abstract
Ground subsidence caused by permafrost thawing causes the formation of thermokarst ponds, where organic compounds from eroding permafrost accumulate. We photolyzed water samples from two such ponds in Northern Quebec and discovered the emission of volatile organic compounds (VOCs) using mass spectrometry. One pond near peat-covered permafrost mounds was organic-rich, while the other near sandy mounds was organic-poor. Compounds up to C10 were detected, comprising the atoms of O, N, and S. The main compounds were methanol, acetaldehyde, and acetone. Hourly VOC fluxes under actinic fluxes similar to local solar fluxes might reach up to 1.7 nmol C m-2 s-1. Unexpectedly, the fluxes of VOCs from the organic-poor pond were greater than those from the organic-rich pond. We suggest that different segregations of organics at the air/water interface may partly explain this observation. This study indicates that sunlit thermokarst ponds are a significant source of atmospheric VOCs, which may affect the environment and climate via ozone and aerosol formation. Further work is required for understanding the relationship between the pond's organic composition and VOC emission fluxes.
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Affiliation(s)
- Tao Wang
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, IRCELYON, 69626 Villeurbanne, France
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science & Engineering, Fudan University, Shanghai 200433, China
| | - Carmen Kalalian
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, IRCELYON, 69626 Villeurbanne, France
| | - Daniel Fillion
- Takuvik Joint International Laboratory, Université Laval (Canada) and CNRS-INSU (France), Pavillon Alexandre-Vachon, Québec G1V 0A6, Canada
- Centre d'Études Nordiques, Université Laval, Pavillon Abitibi-Price, Québec G1 V 0A6, Canada
- Department of Chemistry, Université Laval, Pavillon Alexandre-Vachon, Québec G1 V 0A6, Canada
| | - Sébastien Perrier
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, IRCELYON, 69626 Villeurbanne, France
| | - Jianmin Chen
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science & Engineering, Fudan University, Shanghai 200433, China
| | - Florent Domine
- Takuvik Joint International Laboratory, Université Laval (Canada) and CNRS-INSU (France), Pavillon Alexandre-Vachon, Québec G1V 0A6, Canada
- Centre d'Études Nordiques, Université Laval, Pavillon Abitibi-Price, Québec G1 V 0A6, Canada
- Department of Chemistry, Université Laval, Pavillon Alexandre-Vachon, Québec G1 V 0A6, Canada
| | - Liwu Zhang
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science & Engineering, Fudan University, Shanghai 200433, China
| | - Christian George
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, IRCELYON, 69626 Villeurbanne, France
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10
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Li Z, Xu W, Kang L, Kuzyakov Y, Chen L, He M, Liu F, Zhang D, Zhou W, Liu X, Yang Y. Accelerated organic matter decomposition in thermokarst lakes upon carbon and phosphorus inputs. GLOBAL CHANGE BIOLOGY 2023; 29:6367-6382. [PMID: 37695465 DOI: 10.1111/gcb.16938] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Revised: 08/23/2023] [Accepted: 08/27/2023] [Indexed: 09/12/2023]
Abstract
Mineralization of dissolved organic matter (DOM) in thermokarst lakes plays a non-negligible role in the permafrost carbon (C) cycle, but remains poorly understood due to its complex interactions with external C and nutrient inputs (i.e., aquatic priming and nutrient effects). Based on large-scale lake sampling and laboratory incubations, in combination with 13 C-stable-isotope labeling, optical spectroscopy, and high-throughput sequencing, we examined large-scale patterns and dominant drivers of priming and nutrient effects of DOM biodegradation across 30 thermokarst lakes along a 1100-km transect on the Tibetan Plateau. We observed that labile C and phosphorus (P) rather than nitrogen (N) inputs stimulated DOM biodegradation, with the priming and P effects being 172% and 451% over unamended control, respectively. We also detected significant interactive effects of labile C and nutrient supply on DOM biodegradation, with the combined labile C and nutrient additions inducing stronger microbial mineralization than C or nutrient treatment alone, illustrating that microbial activity in alpine thermokarst lakes is co-limited by both C and nutrients. We further found that the aquatic priming was mainly driven by DOM quality, with the priming intensity increasing with DOM recalcitrance, reflecting the limitation of external C as energy sources for microbial activity. Greater priming intensity was also associated with higher community-level ribosomal RNA gene operon (rrn) copy number and bacterial diversity as well as increased background soluble reactive P concentration. In contrast, the P effect decreased with DOM recalcitrance as well as with background soluble reactive P and ammonium concentrations, revealing the declining importance of P availability in mediating DOM biodegradation with enhanced C limitation but reduced nutrient limitation. Overall, the stimulation of external C and P inputs on DOM biodegradation in thermokarst lakes would amplify C-climate feedback in this alpine permafrost region.
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Affiliation(s)
- Ziliang Li
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, China
- China National Botanical Garden, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Weijie Xu
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, China
- China National Botanical Garden, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Luyao Kang
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, China
- China National Botanical Garden, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Yakov Kuzyakov
- Department of Soil Science of Temperate Ecosystems, University of Göttingen, Göttingen, Germany
- Department of Agricultural Soil Science, University of Göttingen, Göttingen, Germany
- Peoples Friendship University of Russia (RUDN University), Moscow, Russia
| | - Leiyi Chen
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, China
- China National Botanical Garden, Beijing, China
| | - Mei He
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, China
- China National Botanical Garden, Beijing, China
| | - Futing Liu
- Key Laboratory of Forest Ecology and Environment of National Forestry and Grassland Administration, Ecology and Nature Conservation Institute, Chinese Academy of Forestry, Beijing, China
| | - Dianye Zhang
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, China
- China National Botanical Garden, Beijing, China
| | - Wei Zhou
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, China
- China National Botanical Garden, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Xuning Liu
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, China
- China National Botanical Garden, Beijing, China
| | - Yuanhe Yang
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, China
- China National Botanical Garden, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
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11
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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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12
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Harris LI, Olefeldt D, Pelletier N, Blodau C, Knorr KH, Talbot J, Heffernan L, Turetsky M. Permafrost thaw causes large carbon loss in boreal peatlands while changes to peat quality are limited. GLOBAL CHANGE BIOLOGY 2023; 29:5720-5735. [PMID: 37565359 DOI: 10.1111/gcb.16894] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Accepted: 06/16/2023] [Indexed: 08/12/2023]
Abstract
Rapid, ongoing permafrost thaw of peatlands in the discontinuous permafrost zone is exposing a globally significant store of soil carbon (C) to microbial processes. Mineralization and release of this peat C to the atmosphere as greenhouse gases is a potentially important feedback to climate change. Here we investigated the effects of permafrost thaw on peat C at a peatland complex in western Canada. We collected 15 complete peat cores (between 2.7 and 4.5 m deep) along four chronosequences, from elevated permafrost peat plateaus to saturated thermokarst bogs that thawed up to 600 years ago. The peat cores were analysed for peat C storage and peat quality, as indicated by decomposition proxies (FTIR and C/N ratios) and potential decomposability using a 200-day aerobic laboratory incubation. Our results suggest net C loss following thaw, with average total peat C stocks decreasing by ~19.3 ± 7.2 kg C m-2 over <600 years (~13% loss). Average post-thaw accumulation of new peat at the surface over the same period was ~13.1 ± 2.5 kg C m-2 . We estimate ~19% (±5.8%) of deep peat (>40 cm below surface) C is lost following thaw (average 26 ± 7.9 kg C m-2 over <600 years). Our FTIR analysis shows peat below the thaw transition in thermokarst bogs is slightly more decomposed than peat of a similar type and age in permafrost plateaus, but we found no significant changes to the quality or lability of deeper peat across the chronosequences. Our incubation results also showed no increase in C mineralization of deep peat across the chronosequences. While these limited changes in peat quality in deeper peat following permafrost thaw highlight uncertainty in the exact mechanisms and processes for C loss, our analysis of peat C stocks shows large C losses following permafrost thaw in peatlands in western Canada.
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Affiliation(s)
- Lorna I Harris
- Department of Renewable Resources, University of Alberta, Edmonton, Alberta, Canada
- Wildlife Conservation Society Canada, Toronto, Ontario, Canada
| | - David Olefeldt
- Department of Renewable Resources, University of Alberta, Edmonton, Alberta, Canada
- Department of Integrative Biology, University of Guelph, Guelph, Ontario, Canada
| | - Nicolas Pelletier
- Department of Geography and Environmental Studies, Carleton University, Ottawa, Ontario, Canada
| | - Christian Blodau
- Ecohydrology and Biogeochemistry Group, University of Münster, Münster, Germany
| | - Klaus-Holger Knorr
- Ecohydrology and Biogeochemistry Group, University of Münster, Münster, Germany
| | - Julie Talbot
- Département de géographie, Université de Montréal, Montréal, Québec, Canada
| | - Liam Heffernan
- Department of Ecology and Genetics, Uppsala University, Uppsala, Sweden
| | - Merritt Turetsky
- Department of Integrative Biology, University of Guelph, Guelph, Ontario, Canada
- Institute of Arctic and Alpine Research, University of Colorado, Boulder, Colorado, USA
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13
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Su Y, Ran Y, Zhang G, Li X. Remotely sensed lake area changes in permafrost regions of the Arctic and the Tibetan Plateau between 1987 and 2017. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 880:163355. [PMID: 37028667 DOI: 10.1016/j.scitotenv.2023.163355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2023] [Revised: 03/24/2023] [Accepted: 04/03/2023] [Indexed: 05/27/2023]
Abstract
Both gradual and abrupt changes in lake surface area in permafrost regions are crucial for understanding the water cycles in cold regions under climate change. However, seasonal changes in lake area in permafrost regions are not available, and their occurrence conditions are still unclear. Based on remotely sensed water body products at a 30 m resolution, this study provides a detailed comparison of lake area changes across seven basins characterized by clear gradients in climatic, topographic and permafrost conditions in the Arctic and Tibetan Plateau between 1987 and 2017. The results show that the maximum surface area of all lakes net increased by 13.45 %. Among them, the seasonal lake area net increased by 28.66 %, but there was also a 2.48 % loss. The permanent lake area net increased by 6.39 %, and the area loss was approximately 3.22 %. The total permanent lake area generally decreased in the Arctic but increased in the Tibetan Plateau. At lake region scale (0.1° grid), the changes in permanent area of contained lakes were divided into four types including no change, homogeneous changes (only expansion or only shrinkage), heterogeneous changes (expansion neighboring shrinkage) and abrupt changes (newforming or vanishing). The lake regions with heterogeneous changes accounted for over one-quarter of all lake regions. All types of changes in lake regions, especially the heterogeneous changes and abrupt changes (e.g., vanishing), occurred more extensively and intensely on low and flat terrain, in high-density lake regions and in warm permafrost regions. These findings indicate that, considering the increase in surface water balance in these river basins, surface water balance alone cannot fully explain changes in permanent lake area in the permafrost region, and the thawing or disappearance of permafrost plays a tipping point effect on the lake changes.
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Affiliation(s)
- Yang Su
- Heihe Remote Sensing Experimental Research Station, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Youhua Ran
- Heihe Remote Sensing Experimental Research Station, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China; University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Guoqing Zhang
- National Tibetan Plateau Data Center, State Key Laboratory of Tibetan Plateau Earth System, Environment and Resources, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China
| | - Xin Li
- National Tibetan Plateau Data Center, State Key Laboratory of Tibetan Plateau Earth System, Environment and Resources, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China
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14
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Hu J, Kang L, Li Z, Feng X, Liang C, Wu Z, Zhou W, Liu X, Yang Y, Chen L. Photo-produced aromatic compounds stimulate microbial degradation of dissolved organic carbon in thermokarst lakes. Nat Commun 2023; 14:3681. [PMID: 37344478 DOI: 10.1038/s41467-023-39432-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Accepted: 06/13/2023] [Indexed: 06/23/2023] Open
Abstract
Photochemical and biological degradation of dissolved organic carbon (DOC) and their interactions jointly contribute to the carbon dioxide released from surface waters in permafrost regions. However, the mechanisms that govern the coupled photochemical and biological degradation of DOC are still poorly understood in thermokarst lakes. Here, by combining Fourier transform ion cyclotron resonance mass spectrometry and microbial high-throughput sequencing, we conducted a sunlight and microbial degradation experiment using water samples collected from 10 thermokarst lakes along a 1100-km permafrost transect. We demonstrate that the enhancement of sunlight on DOC biodegradation is not associated with the low molecular weight aliphatics produced by sunlight, but driven by the photo-produced aromatics. This aromatic compound-driven acceleration of biodegradation may be attributed to the potential high abilities of the microbes to decompose complex compounds in thermokarst lakes. These findings highlight the importance of aromatics in regulating the sunlight effects on DOC biodegradation in permafrost-affected lakes.
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Affiliation(s)
- Jie Hu
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Luyao Kang
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Ziliang Li
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Xuehui Feng
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Caifan Liang
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Zan Wu
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
| | - Wei Zhou
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Xuning Liu
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yuanhe Yang
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Leiyi Chen
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China.
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15
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Yang G, Zheng Z, Abbott BW, Olefeldt D, Knoblauch C, Song Y, Kang L, Qin S, Peng Y, Yang Y. Characteristics of methane emissions from alpine thermokarst lakes on the Tibetan Plateau. Nat Commun 2023; 14:3121. [PMID: 37253726 DOI: 10.1038/s41467-023-38907-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Accepted: 05/18/2023] [Indexed: 06/01/2023] Open
Abstract
Understanding methane (CH4) emission from thermokarst lakes is crucial for predicting the impacts of abrupt thaw on the permafrost carbon-climate feedback. However, observational evidence, especially from high-altitude permafrost regions, is still scarce. Here, by combining field surveys, radio- and stable-carbon isotopic analyses, and metagenomic sequencing, we present multiple characteristics of CH4 emissions from 120 thermokarst lakes in 30 clusters along a 1100 km transect on the Tibetan Plateau. We find that thermokarst lakes have high CH4 emissions during the ice-free period (13.4 ± 1.5 mmol m-2 d-1; mean ± standard error) across this alpine permafrost region. Ebullition constitutes 84% of CH4 emissions, which are fueled primarily by young carbon decomposition through the hydrogenotrophic pathway. The relative abundances of methanogenic genes correspond to the observed CH4 fluxes. Overall, multiple parameters obtained in this study provide benchmarks for better predicting the strength of permafrost carbon-climate feedback in high-altitude permafrost regions.
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Affiliation(s)
- Guibiao Yang
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
| | - Zhihu Zheng
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Benjamin W Abbott
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, UT, 84602, USA
| | - David Olefeldt
- Department of Renewable Resources, University of Alberta, Edmonton, Alberta, T6G 2H1, Canada
| | | | - Yutong Song
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Luyao Kang
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Shuqi Qin
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
| | - Yunfeng Peng
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
| | - Yuanhe Yang
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China.
- University of Chinese Academy of Sciences, Beijing, 100049, China.
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16
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Mao C, Song Y, Peng Y, Kang L, Li Z, Zhou W, Liu X, Liu F, Zhu G, Yang Y. Patterns and drivers of anaerobic nitrogen transformations in sediments of thermokarst lakes. GLOBAL CHANGE BIOLOGY 2023; 29:2697-2713. [PMID: 36840688 DOI: 10.1111/gcb.16654] [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: 11/15/2022] [Accepted: 01/24/2023] [Indexed: 05/31/2023]
Abstract
Significant attention has been given to the way in which the soil nitrogen (N) cycle responds to permafrost thaw in recent years, yet little is known about anaerobic N transformations in thermokarst lakes, which account for more than one-third of thermokarst landforms across permafrost regions. Based on the N isotope dilution and tracing technique, combined with qPCR and high-throughput sequencing, we presented large-scale measurements of anaerobic N transformations of sediments across 30 thermokarst lakes over the Tibetan alpine permafrost region. Our results showed that gross N mineralization, ammonium immobilization, and dissimilatory nitrate reduction rates in thermokarst lakes were higher in the eastern part of our study area than in the west. Denitrification dominated in the dissimilatory nitrate reduction processes, being two and one orders of magnitude higher than anaerobic ammonium oxidation (anammox) and dissimilatory nitrate reduction to ammonium (DNRA), respectively. The abundances of the dissimilatory nitrate reduction genes (nirK, nirS, hzsB, and nrfA) exhibited patterns consistent with sediment N transformation rates, while α diversity did not. The inter-lake variability in gross N mineralization and ammonium immobilization was dominantly driven by microbial biomass, while the variability in anammox and DNRA was driven by substrate supply and organic carbon content, respectively. Denitrification was jointly affected by nirS abundance and organic carbon content. Overall, the patterns and drivers of anaerobic N transformation rates detected in this study provide a new perspective on potential N release, retention, and removal upon the formation and development of thermokarst lakes.
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Affiliation(s)
- Chao Mao
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, China
| | - Yutong Song
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Yunfeng Peng
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, China
| | - Luyao Kang
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Ziliang Li
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Wei Zhou
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Xuning Liu
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Futing Liu
- Key Laboratory of Forest Ecology and Environment of National Forestry and Grassland Administration, Ecology and Nature Conservation Institute, Chinese Academy of Forestry, Beijing, China
| | - Guibing Zhu
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, China
| | - Yuanhe Yang
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
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17
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Yang S, Anthony SE, Jenrich M, In 't Zandt MH, Strauss J, Overduin PP, Grosse G, Angelopoulos M, Biskaborn BK, Grigoriev MN, Wagner D, Knoblauch C, Jaeschke A, Rethemeyer J, Kallmeyer J, Liebner S. Microbial methane cycling in sediments of Arctic thermokarst lagoons. GLOBAL CHANGE BIOLOGY 2023; 29:2714-2731. [PMID: 36811358 DOI: 10.1111/gcb.16649] [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: 07/01/2022] [Accepted: 01/27/2023] [Indexed: 05/31/2023]
Abstract
Thermokarst lagoons represent the transition state from a freshwater lacustrine to a marine environment, and receive little attention regarding their role for greenhouse gas production and release in Arctic permafrost landscapes. We studied the fate of methane (CH4 ) in sediments of a thermokarst lagoon in comparison to two thermokarst lakes on the Bykovsky Peninsula in northeastern Siberia through the analysis of sediment CH4 concentrations and isotopic signature, methane-cycling microbial taxa, sediment geochemistry, lipid biomarkers, and network analysis. We assessed how differences in geochemistry between thermokarst lakes and thermokarst lagoons, caused by the infiltration of sulfate-rich marine water, altered the microbial methane-cycling community. Anaerobic sulfate-reducing ANME-2a/2b methanotrophs dominated the sulfate-rich sediments of the lagoon despite its known seasonal alternation between brackish and freshwater inflow and low sulfate concentrations compared to the usual marine ANME habitat. Non-competitive methylotrophic methanogens dominated the methanogenic community of the lakes and the lagoon, independent of differences in porewater chemistry and depth. This potentially contributed to the high CH4 concentrations observed in all sulfate-poor sediments. CH4 concentrations in the freshwater-influenced sediments averaged 1.34 ± 0.98 μmol g-1 , with highly depleted δ13 C-CH4 values ranging from -89‰ to -70‰. In contrast, the sulfate-affected upper 300 cm of the lagoon exhibited low average CH4 concentrations of 0.011 ± 0.005 μmol g-1 with comparatively enriched δ13 C-CH4 values of -54‰ to -37‰ pointing to substantial methane oxidation. Our study shows that lagoon formation specifically supports methane oxidizers and methane oxidation through changes in pore water chemistry, especially sulfate, while methanogens are similar to lake conditions.
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Affiliation(s)
- Sizhong Yang
- GFZ German Research Center for Geosciences, Helmholtz Centre Potsdam, Section Geomicrobiology, Potsdam, Germany
- Cryosphere Research Station on the Qinghai-Tibet Plateau, State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, China
| | - Sara E Anthony
- Institute of Geology and Mineralogy, University of Cologne, Cologne, Germany
| | - Maren Jenrich
- Permafrost Research Section, Alfred Wegener Institute Helmholtz Center for Polar and Marine Research, Potsdam, Germany
- Institute of Geosciences, University of Potsdam, Potsdam, Germany
| | - Michiel H In 't Zandt
- Department of Microbiology, RIBES, Radboud University, Nijmegen, the Netherlands
- Netherlands Earth System Science Center, Utrecht University, Utrecht, the Netherlands
| | - Jens Strauss
- Permafrost Research Section, Alfred Wegener Institute Helmholtz Center for Polar and Marine Research, Potsdam, Germany
| | - Pier Paul Overduin
- Permafrost Research Section, Alfred Wegener Institute Helmholtz Center for Polar and Marine Research, Potsdam, Germany
| | - Guido Grosse
- Permafrost Research Section, Alfred Wegener Institute Helmholtz Center for Polar and Marine Research, Potsdam, Germany
- Institute of Geosciences, University of Potsdam, Potsdam, Germany
| | - Michael Angelopoulos
- Permafrost Research Section, Alfred Wegener Institute Helmholtz Center for Polar and Marine Research, Potsdam, Germany
| | - Boris K Biskaborn
- Polar Terrestrial Environmental Systems Section, Alfred Wegener Institute Helmholtz Center for Polar and Marine Research, Potsdam, Germany
| | - Mikhail N Grigoriev
- Laboratory of General Geocryology, Melnikov Permafrost Institute, Siberian Branch of the Russian Academy of Sciences, Yakutsk, Russia
| | - Dirk Wagner
- GFZ German Research Center for Geosciences, Helmholtz Centre Potsdam, Section Geomicrobiology, Potsdam, Germany
- Institute of Geosciences, University of Potsdam, Potsdam, Germany
| | - Christian Knoblauch
- Institute of Soil Science, Universität Hamburg, Hamburg, Germany
- Center for Earth System Research and Sustainability, Universität Hamburg, Hamburg, Germany
| | - Andrea Jaeschke
- Institute of Geology and Mineralogy, University of Cologne, Cologne, Germany
| | - Janet Rethemeyer
- Institute of Geology and Mineralogy, University of Cologne, Cologne, Germany
| | - Jens Kallmeyer
- GFZ German Research Center for Geosciences, Helmholtz Centre Potsdam, Section Geomicrobiology, Potsdam, Germany
| | - Susanne Liebner
- GFZ German Research Center for Geosciences, Helmholtz Centre Potsdam, Section Geomicrobiology, Potsdam, Germany
- Institute of Biochemistry and Biology, University of Potsdam, Potsdam, Germany
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18
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Mu C, Mu M, Wu X, Jia L, Fan C, Peng X, Ping CL, Wu Q, Xiao C, Liu J. High carbon emissions from thermokarst lakes and their determinants in the Tibet Plateau. GLOBAL CHANGE BIOLOGY 2023; 29:2732-2745. [PMID: 36854541 DOI: 10.1111/gcb.16658] [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: 09/28/2022] [Accepted: 02/21/2023] [Indexed: 05/31/2023]
Abstract
Thermokarst lakes are potentially important sources of methane (CH4 ) and carbon dioxide (CO2 ). However, considerable uncertainty exists regarding carbon emissions from thermokarst lakes owing to a limited understanding of their patterns and motivators. In this study, we measured CH4 and CO2 diffusive fluxes in 163 thermokarst lakes in the Qinghai-Tibet Plateau (QTP) over 3 years from May to October. The median carbon emissions from the QTP thermokarst lakes were 1440 mg CO2 m-2 day-1 and 60 mg CH4 m-2 day-1 , respectively. The diffusive rates of CO2 and CH4 are related to the catchment land cover type. Sediment microbial abundance and hydrochemistry explain 51.9% and 38.3% of the total variance in CH4 diffusive emissions, respectively, while CO2 emissions show no significant relationship with environmental factors. When upscaling carbon emissions from the QTP thermokarst lakes, the annual average CH4 release per lake area is equal to that of the pan-Arctic region. Our findings highlight the importance of incorporating in situ observation data with different emission pathways for different land cover types in predicting carbon emissions from thermokarst lakes in the future.
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Affiliation(s)
- Cuicui Mu
- Key Laboratory of Western China's Environmental Systems (Ministry of Education), College of Earth and Environmental Sciences, Observation and Research Station on Eco-Environment of Frozen Ground in the Qilian Mountains, Lanzhou University, Lanzhou, China
- Cryosphere Research Station on the Qinghai-Tibet Plateau, State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, China
- Southern Marine Science and Engineering Guangdong Laboratory, Zhuhai, China
| | - Mei Mu
- Key Laboratory of Western China's Environmental Systems (Ministry of Education), College of Earth and Environmental Sciences, Observation and Research Station on Eco-Environment of Frozen Ground in the Qilian Mountains, Lanzhou University, Lanzhou, China
| | - Xiaodong Wu
- Cryosphere Research Station on the Qinghai-Tibet Plateau, State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, China
| | - Lin Jia
- Key Laboratory of Western China's Environmental Systems (Ministry of Education), College of Earth and Environmental Sciences, Observation and Research Station on Eco-Environment of Frozen Ground in the Qilian Mountains, Lanzhou University, Lanzhou, China
| | - Chenyan Fan
- Key Laboratory of Western China's Environmental Systems (Ministry of Education), College of Earth and Environmental Sciences, Observation and Research Station on Eco-Environment of Frozen Ground in the Qilian Mountains, Lanzhou University, Lanzhou, China
| | - Xiaoqing Peng
- Key Laboratory of Western China's Environmental Systems (Ministry of Education), College of Earth and Environmental Sciences, Observation and Research Station on Eco-Environment of Frozen Ground in the Qilian Mountains, Lanzhou University, Lanzhou, China
| | - Chien-Lu Ping
- University of Alaska Fairbanks, Fairbanks, Alaska, USA
| | - Qingbai Wu
- State Key Laboratory of Frozen Soil Engineering, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, China
- Beiluhe Observation and Research Station on Frozen Soil Engineering and Environment in the Qinghai-Tibetan Plateau, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, China
| | - Cunde Xiao
- State Key Laboratory of Earth Surface Processes and Resource Ecology, Beijing Normal University, Beijing, China
| | - Jianbao Liu
- Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, China
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19
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Jonsson S, Mastromonaco MN, Wang F, Bravo AG, Cairns WRL, Chételat J, Douglas TA, Lescord G, Ukonmaanaho L, Heimbürger-Boavida LE. Arctic methylmercury cycling. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 850:157445. [PMID: 35882324 DOI: 10.1016/j.scitotenv.2022.157445] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 07/12/2022] [Accepted: 07/13/2022] [Indexed: 06/15/2023]
Abstract
Anthropogenic mercury (Hg) undergoes long-range transport to the Arctic where some of it is transformed into methylmercury (MeHg), potentially leading to high exposure in some Arctic inhabitants and wildlife. The environmental exposure of Hg is determined not just by the amount of Hg entering the Arctic, but also by biogeochemical and ecological processes occurring in the Arctic. These processes affect MeHg uptake in biota by regulating the bioavailability, methylation and demethylation, bioaccumulation and biomagnification of MeHg in Arctic ecosystems. Here, we present a new budget for pools and fluxes of MeHg in the Arctic and review the scientific advances made in the last decade on processes leading to environmental exposure to Hg. Methylation and demethylation are key processes controlling the pool of MeHg available for bioaccumulation. Methylation of Hg occurs in diverse Arctic environments including permafrost, sediments and the ocean water column, and is primarily a process carried out by microorganisms. While microorganisms carrying the hgcAB gene pair (responsible for Hg methylation) have been identified in Arctic soils and thawing permafrost, the formation pathway of MeHg in oxic marine waters remains less clear. Hotspots for methylation of Hg in terrestrial environments include thermokarst wetlands, ponds and lakes. The shallow sub-surface enrichment of MeHg in the Arctic Ocean, in comparison to other marine systems, is a possible explanation for high MeHg concentrations in some Arctic biota. Bioconcentration of aqueous MeHg in bacteria and algae is a critical step in the transfer of Hg to top predators, which may be dampened or enhanced by the presence of organic matter. Variable trophic position has an important influence on MeHg concentrations among populations of top predator species such as ringed seal and polar bears distributed across the circumpolar Arctic. These scientific advances highlight key processes that affect the fate of anthropogenic Hg deposited to Arctic environments.
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Affiliation(s)
- Sofi Jonsson
- Department of Environmental Science, Stockholm University, SE-106 91 Stockholm, Sweden.
| | | | - Feiyue Wang
- Centre for Earth Observation Science, and Department of Environment and Geography, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Andrea G Bravo
- Department of Marine Biology and Oceanography, Institut de Ciències del Mar (ICM-CSIC), Barcelona, Spain
| | - Warren R L Cairns
- CNR Institute of Polar Sciences and Ca' Foscari University, Venice, Italy
| | - John Chételat
- Environment and Climate Change Canada, National Wildlife Research Centre, Ottawa, ON, Canada
| | - Thomas A Douglas
- U.S. Army Cold Regions Research and Engineering Laboratory, Fort Wainwright, AK, USA
| | - Gretchen Lescord
- Wildlife Conservation Society Canada and Laurentian University, Vale Living with Lakes Center, Sudbury, Ontario, Canada
| | - Liisa Ukonmaanaho
- Natural Resources Institute Finland (Luke), P.O. Box 2, FI-00791 Helsinki, Finland
| | - Lars-Eric Heimbürger-Boavida
- CNRS/INSU,Aix Marseille Université,Université de Toulon, IRD, Mediterranean Institute of Oceanography (MIO), Marseille, France
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20
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Kwon MJ, Ballantyne A, Ciais P, Qiu C, Salmon E, Raoult N, Guenet B, Göckede M, Euskirchen ES, Nykänen H, Schuur EAG, Turetsky MR, Dieleman CM, Kane ES, Zona D. Lowering water table reduces carbon sink strength and carbon stocks in northern peatlands. GLOBAL CHANGE BIOLOGY 2022; 28:6752-6770. [PMID: 36039832 PMCID: PMC9805217 DOI: 10.1111/gcb.16394] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Accepted: 07/04/2022] [Indexed: 06/15/2023]
Abstract
Peatlands at high latitudes have accumulated >400 Pg carbon (C) because saturated soil and cold temperatures suppress C decomposition. This substantial amount of C in Arctic and Boreal peatlands is potentially subject to increased decomposition if the water table (WT) decreases due to climate change, including permafrost thaw-related drying. Here, we optimize a version of the Organizing Carbon and Hydrology In Dynamic Ecosystems model (ORCHIDEE-PCH4) using site-specific observations to investigate changes in CO2 and CH4 fluxes as well as C stock responses to an experimentally manipulated decrease of WT at six northern peatlands. The unmanipulated control peatlands, with the WT <20 cm on average (seasonal max up to 45 cm) below the surface, currently act as C sinks in most years (58 ± 34 g C m-2 year-1 ; including 6 ± 7 g C-CH4 m-2 year-1 emission). We found, however, that lowering the WT by 10 cm reduced the CO2 sink by 13 ± 15 g C m-2 year-1 and decreased CH4 emission by 4 ± 4 g CH4 m-2 year-1 , thus accumulating less C over 100 years (0.2 ± 0.2 kg C m-2 ). Yet, the reduced emission of CH4 , which has a larger greenhouse warming potential, resulted in a net decrease in greenhouse gas balance by 310 ± 360 g CO2-eq m-2 year-1 . Peatlands with the initial WT close to the soil surface were more vulnerable to C loss: Non-permafrost peatlands lost >2 kg C m-2 over 100 years when WT is lowered by 50 cm, while permafrost peatlands temporally switched from C sinks to sources. These results highlight that reductions in C storage capacity in response to drying of northern peatlands are offset in part by reduced CH4 emissions, thus slightly reducing the positive carbon climate feedbacks of peatlands under a warmer and drier future climate scenario.
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Affiliation(s)
- Min Jung Kwon
- Laboratoire des Sciences du Climat et de l'EnvironnementCEA‐CNRS‐UVSQGif‐sur‐YvetteFrance
- Institute of Soil ScienceUniversity of HamburgHamburgGermany
| | - Ashley Ballantyne
- Laboratoire des Sciences du Climat et de l'EnvironnementCEA‐CNRS‐UVSQGif‐sur‐YvetteFrance
- Department of Ecosystem and Conservation ScienceUniversity of MontanaMissoulaMontanaUSA
| | - Philippe Ciais
- Laboratoire des Sciences du Climat et de l'EnvironnementCEA‐CNRS‐UVSQGif‐sur‐YvetteFrance
| | - Chunjing Qiu
- Laboratoire des Sciences du Climat et de l'EnvironnementCEA‐CNRS‐UVSQGif‐sur‐YvetteFrance
- INRAE, AgroParisTech, Université Paris‐SaclayGif‐sur‐YvetteFrance
| | - Elodie Salmon
- Laboratoire des Sciences du Climat et de l'EnvironnementCEA‐CNRS‐UVSQGif‐sur‐YvetteFrance
| | - Nina Raoult
- Laboratoire des Sciences du Climat et de l'EnvironnementCEA‐CNRS‐UVSQGif‐sur‐YvetteFrance
| | - Bertrand Guenet
- Laboratoire des Sciences du Climat et de l'EnvironnementCEA‐CNRS‐UVSQGif‐sur‐YvetteFrance
- Laboratoire de Géologie, Ecole Normale SupérieureCNRS, PSL Research UniversityParisFrance
| | - Mathias Göckede
- Systems DepartmentMax Planck Institute for BiogeochemistryJenaGermany
| | | | - Hannu Nykänen
- Department of Environmental and Biological SciencesUniversity of Eastern FinlandKuopioFinland
| | - Edward A. G. Schuur
- College of the Environment, Forestry, and Natural SciencesNorthern Arizona UniversityFlagstaffArizonaUSA
| | - Merritt R. Turetsky
- Institute of Arctic and Alpine ResearchUniversity of ColoradoBoulderColoradoUSA
| | | | - Evan S. Kane
- College of Forest Resources and Environmental ScienceMichigan Technological UniversityHoughtonMichiganUSA
- USDA Forest Service Northern Research StationHoughtonMichiganUSA
| | - Donatella Zona
- Department of Animal and Plant ScienceUniversity of SheffieldSheffieldUK
- Department of BiologySan Diego State UniversitySan DiegoCaliforniaUSA
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21
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A globally relevant stock of soil nitrogen in the Yedoma permafrost domain. Nat Commun 2022; 13:6074. [PMID: 36241637 PMCID: PMC9568517 DOI: 10.1038/s41467-022-33794-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Accepted: 09/22/2022] [Indexed: 12/24/2022] Open
Abstract
Nitrogen regulates multiple aspects of the permafrost climate feedback, including plant growth, organic matter decomposition, and the production of the potent greenhouse gas nitrous oxide. Despite its importance, current estimates of permafrost nitrogen are highly uncertain. Here, we compiled a dataset of >2000 samples to quantify nitrogen stocks in the Yedoma domain, a region with organic-rich permafrost that contains ~25% of all permafrost carbon. We estimate that the Yedoma domain contains 41.2 gigatons of nitrogen down to ~20 metre for the deepest unit, which increases the previous estimate for the entire permafrost zone by ~46%. Approximately 90% of this nitrogen (37 gigatons) is stored in permafrost and therefore currently immobile and frozen. Here, we show that of this amount, ¾ is stored >3 metre depth, but if partially mobilised by thaw, this large nitrogen pool could have continental-scale consequences for soil and aquatic biogeochemistry and global-scale consequences for the permafrost feedback.
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22
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Armstrong McKay DI, Staal A, Abrams JF, Winkelmann R, Sakschewski B, Loriani S, Fetzer I, Cornell SE, Rockström J, Lenton TM. Exceeding 1.5°C global warming could trigger multiple climate tipping points. Science 2022; 377:eabn7950. [PMID: 36074831 DOI: 10.1126/science.abn7950] [Citation(s) in RCA: 246] [Impact Index Per Article: 123.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Climate tipping points occur when change in a part of the climate system becomes self-perpetuating beyond a warming threshold, leading to substantial Earth system impacts. Synthesizing paleoclimate, observational, and model-based studies, we provide a revised shortlist of global "core" tipping elements and regional "impact" tipping elements and their temperature thresholds. Current global warming of ~1.1°C above preindustrial temperatures already lies within the lower end of some tipping point uncertainty ranges. Several tipping points may be triggered in the Paris Agreement range of 1.5 to <2°C global warming, with many more likely at the 2 to 3°C of warming expected on current policy trajectories. This strengthens the evidence base for urgent action to mitigate climate change and to develop improved tipping point risk assessment, early warning capability, and adaptation strategies.
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Affiliation(s)
- David I Armstrong McKay
- Stockholm Resilience Centre, Stockholm University, Stockholm, Sweden.,Bolin Centre for Climate Research, Stockholm University, Stockholm, Sweden.,Global Systems Institute, University of Exeter, Exeter, UK.,Georesilience Analytics, Leatherhead, UK
| | - Arie Staal
- Stockholm Resilience Centre, Stockholm University, Stockholm, Sweden.,Bolin Centre for Climate Research, Stockholm University, Stockholm, Sweden.,Copernicus Institute of Sustainable Development, Utrecht University, Utrecht, Netherlands
| | - Jesse F Abrams
- Global Systems Institute, University of Exeter, Exeter, UK
| | | | | | - Sina Loriani
- Potsdam Institute for Climate Impact Research, Potsdam, Germany
| | - Ingo Fetzer
- Stockholm Resilience Centre, Stockholm University, Stockholm, Sweden.,Bolin Centre for Climate Research, Stockholm University, Stockholm, Sweden
| | - Sarah E Cornell
- Stockholm Resilience Centre, Stockholm University, Stockholm, Sweden.,Bolin Centre for Climate Research, Stockholm University, Stockholm, Sweden
| | - Johan Rockström
- Stockholm Resilience Centre, Stockholm University, Stockholm, Sweden.,Potsdam Institute for Climate Impact Research, Potsdam, Germany
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23
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Recent climate change has driven divergent hydrological shifts in high-latitude peatlands. Nat Commun 2022; 13:4959. [PMID: 36002465 PMCID: PMC9402595 DOI: 10.1038/s41467-022-32711-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Accepted: 08/10/2022] [Indexed: 11/08/2022] Open
Abstract
High-latitude peatlands are changing rapidly in response to climate change, including permafrost thaw. Here, we reconstruct hydrological conditions since the seventeenth century using testate amoeba data from 103 high-latitude peat archives. We show that 54% of the peatlands have been drying and 32% have been wetting over this period, illustrating the complex ecohydrological dynamics of high latitude peatlands and their highly uncertain responses to a warming climate. A recent synthesis study found 54% of the high-latitude peatlands have been drying and 32% have been wetting over the past centuries, illustrating their complex ecohydrological dynamics and highly uncertain responses to a warming climate.
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24
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Microbiogeochemical Traits to Identify Nitrogen Hotspots in Permafrost Regions. NITROGEN 2022. [DOI: 10.3390/nitrogen3030031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Permafrost-affected tundra soils are large carbon (C) and nitrogen (N) reservoirs. However, N is largely bound in soil organic matter (SOM), and ecosystems generally have low N availability. Therefore, microbial induced N-cycling processes and N losses were considered negligible. Recent studies show that microbial N processing rates, inorganic N availability, and lateral N losses from thawing permafrost increase when vegetation cover is disturbed, resulting in reduced N uptake or increased N input from thawing permafrost. In this review, we describe currently known N hotspots, particularly bare patches in permafrost peatland or permafrost soils affected by thermokarst, and their microbiogeochemical characteristics, and present evidence for previously unrecorded N hotspots in the tundra. We summarize the current understanding of microbial N cycling processes that promote the release of the potent greenhouse gas (GHG) nitrous oxide (N2O) and the translocation of inorganic N from terrestrial into aquatic ecosystems. We suggest that certain soil characteristics and microbial traits can be used as indicators of N availability and N losses. Identifying N hotspots in permafrost soils is key to assessing the potential for N release from permafrost-affected soils under global warming, as well as the impact of increased N availability on emissions of carbon-containing GHGs.
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25
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The Polar Fox Lagoon in Siberia harbours a community of Bathyarchaeota possessing the potential for peptide fermentation and acetogenesis. Antonie Van Leeuwenhoek 2022; 115:1229-1244. [PMID: 35947314 PMCID: PMC9534799 DOI: 10.1007/s10482-022-01767-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Accepted: 07/18/2022] [Indexed: 11/05/2022]
Abstract
Archaea belonging to the phylum Bathyarchaeota are the predominant archaeal species in cold, anoxic marine sediments and additionally occur in a variety of habitats, both natural and man-made. Metagenomic and single-cell sequencing studies suggest that Bathyarchaeota may have a significant impact on the emissions of greenhouse gases into the atmosphere, either through direct production of methane or through the degradation of complex organic matter that can subsequently be converted into methane. This is especially relevant in permafrost regions where climate change leads to thawing of permafrost, making high amounts of stored carbon bioavailable. Here we present the analysis of nineteen draft genomes recovered from a sediment core metagenome of the Polar Fox Lagoon, a thermokarst lake located on the Bykovsky Peninsula in Siberia, Russia, which is connected to the brackish Tiksi Bay. We show that the Bathyarchaeota in this lake are predominantly peptide degraders, producing reduced ferredoxin from the fermentation of peptides, while degradation pathways for plant-derived polymers were found to be incomplete. Several genomes encoded the potential for acetogenesis through the Wood-Ljungdahl pathway, but methanogenesis was determined to be unlikely due to the lack of genes encoding the key enzyme in methanogenesis, methyl-CoM reductase. Many genomes lacked a clear pathway for recycling reduced ferredoxin. Hydrogen metabolism was also hardly found: one type 4e [NiFe] hydrogenase was annotated in a single MAG and no [FeFe] hydrogenases were detected. Little evidence was found for syntrophy through formate or direct interspecies electron transfer, leaving a significant gap in our understanding of the metabolism of these organisms.
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26
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Wei Z, Du Z, Wang L, Zhong W, Lin J, Xu Q, Xiao C. Sedimentary organic carbon storage of thermokarst lakes and ponds across Tibetan permafrost region. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 831:154761. [PMID: 35339557 DOI: 10.1016/j.scitotenv.2022.154761] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2022] [Revised: 03/15/2022] [Accepted: 03/18/2022] [Indexed: 06/14/2023]
Abstract
Sedimentary soil organic carbon (SOC) stored in thermokarst lakes and ponds (hereafter referred to as thaw lakes) across high-latitude/altitude permafrost areas is of global significance due to increasing thaw lake numbers and their high C vulnerability under climate warming. However, to date, little is known about the SOC storage in these lakes, which limits our better understanding of the fate of these active carbon in a warming future. Here, by combining large-scale field observation data and published deep (e.g., 0-300 cm) permafrost SOC data with a random forest (RF) machine learning technique, we provided the first comprehensive estimation of thaw lake SOC stocks to 3 m depth on the Tibetan Plateau. This study demonstrated that combining multiple environmental factors with the RF model could effectively predict the spatial distributions of the thaw lake SOC density values (SOCDs). The model results revealed that the soil respiration, normalized difference vegetation index (NDVI), and mean annual precipitation (MAP) were the most influential factors for predicting thaw lake SOCDs. In total, the sedimentary SOC stocks in the thaw lakes were approximately 52.62 Tg in the top 3 m, with 53% of the SOC stored in the upper layers (0-100 cm). The SOCDs generally exhibited high values in eastern Tibetan Plateau, and low values in mid- and western Tibetan Plateau, which were similar to the patterns of the land cover types that affected the SOCDs. We further found that the SOCDs of thaw lakes were generally higher than those of their surrounding permafrost soils at different layer depths, which could be ascribed to the erosion of soil particles or leaching solution from the thawing permafrost soils to lakes and/or enhanced vegetation growth at the lake bottom. This research highlights the necessity of explicitly considering the thaw lake SOC stocks in Earth system models for more comprehensive future projections of the carbon dynamics on the plateau.
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Affiliation(s)
- Zhiqiang Wei
- Zhuhai Branch of State Key Laboratory of Earth Surface Process and Resource Ecology, Beijing Normal University, Zhuhai 519087, China
| | - Zhiheng Du
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China
| | - Lei Wang
- State Key Laboratory of Earth Surface Processes and Resource Ecology, Beijing Normal University, Beijing 100875, China
| | - Wei Zhong
- School of Geography Sciences, South China Normal University, Guangzhou 510631, China
| | - Jiahui Lin
- State Key Laboratory of Earth Surface Processes and Resource Ecology, Beijing Normal University, Beijing 100875, China
| | - Qian Xu
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China
| | - Cunde Xiao
- State Key Laboratory of Earth Surface Processes and Resource Ecology, Beijing Normal University, Beijing 100875, China.
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27
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Wang G, Chen L, Zhang D, Qin S, Peng Y, Yang G, Wang J, Yu J, Wei B, Liu Y, Li Q, Kang L, Wang Y, Yang Y. Divergent Trajectory of Soil Autotrophic and Heterotrophic Respiration upon Permafrost Thaw. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:10483-10493. [PMID: 35748652 DOI: 10.1021/acs.est.1c07575] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Warming-induced permafrost thaw may stimulate soil respiration (Rs) and thus cause a positive feedback to climate warming. However, due to the limited in situ observations, it remains unclear about how Rs and its autotrophic (Ra) and heterotrophic (Rh) components change upon permafrost thaw. Here we monitored variations in Rs and its components along a permafrost thaw sequence on the Tibetan Plateau, and explored the potential linkage of Rs components (i.e., Ra and Rh) with biotic (e.g., plant functional traits and soil microbial diversity) and abiotic factors (e.g., substrate quality). We found that Ra and Rh exhibited divergent responses to permafrost collapse: Ra increased with the time of thawing, while Rh exhibited a hump-shaped pattern along the thaw sequence. We also observed different drivers of thaw-induced changes in the ratios of Ra:Rs and Rh:Rs. Except for soil water status, plant community structure, diversity, and root properties explained the variation in Ra:Rs ratio, soil substrate quality and microbial diversity were key factors associated with the dynamics of Rh:Rs ratio. Overall, these findings demonstrate divergent patterns and drivers of Rs components as permafrost thaw prolongs, which call for considerations in Earth system models for better forecasting permafrost carbon-climate feedback.
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Affiliation(s)
- Guanqin Wang
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Leiyi Chen
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - Dianye Zhang
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - Shuqi Qin
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yunfeng Peng
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - Guibiao Yang
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - Jun Wang
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jianchun Yu
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Bin Wei
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yang Liu
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
- College of Resources and Environmental Science/Hebei Province Key Laboratory for Farmland Eco-Environment, Agricultural University of Hebei, Baoding 071000, China
| | - Qinlu Li
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Luyao Kang
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yuanyuan Wang
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - Yuanhe Yang
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
- University of Chinese Academy of Sciences, Beijing 100049, China
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Shen R, Yang H, Rinklebe J, Bolan N, Hu Q, Huang X, Wen X, Zheng B, Shi L. Seasonal flooding wetland expansion would strongly affect soil and sediment organic carbon storage and carbon-nutrient stoichiometry. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 828:154427. [PMID: 35288135 DOI: 10.1016/j.scitotenv.2022.154427] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Revised: 02/04/2022] [Accepted: 03/05/2022] [Indexed: 06/14/2023]
Abstract
In the past few decades, many non-flooding uplands (NF) and permanent flooding waters (PF) have been turned into seasonal flooding wetlands (SF) at the global scale. This trend could severely threaten global climate system by changing carbon cycling in terrestrial and aquatic ecosystems. However, the effects of SF expansion on soil and sediment organic carbon (SOC) storage and carbon-nutrient stoichiometry are far from clearly understood. Therefore, we explored SOC storage and carbon-nutrient stoichiometry among adjacent NF, SF and PF using 817 samples at 0-100 cm depth increment at Poyang Lake and Shengjin Lake in the middle-lower Yangtze River floodplain, China. The SFs of the two lakes were both Carex lakeshore wetlands. The NF of Shengjin Lake was a near-natural forest, while the NF of Poyang Lake was a disturbed grassland. The results showed that SOC storage at SFs of Poyang Lake and Shengjin Lake was 75.61 and 98.01 Mg C/ha at 0-100 cm depth increment. The difference in SOC storage among nearby NF, SF and PF depended on depth and disturbance. SOC storage at SF was equivalent to that at near-natural NF, but was much higher than that at disturbed NF. SOC storage at SF was 12.62%-24.50% higher than that at PF at 0-30 cm depth increment, but was 15.16%-25.87% lower than that at PF at 0-100 cm depth increment. Edaphic carbon and nutrients followed allometric relationships at most sites and C increased faster than N and P along the depth gradients. Carbon-nutrient stoichiometric relationships at SF and PF were similar, and were more coupled than those at near-natural NF. This research illustrates the strong effects of seasonal flooding on SOC sequestration in terrestrial and aquatic ecosystems, and expands our understanding of carbon cycling in these two ecosystems.
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Affiliation(s)
- Ruichang Shen
- Jiangxi Province Key Laboratory of Watershed Ecosystem Change and Biodiversity, Center for Watershed Ecology, Institute of Life Science and School of Life Science, Nanchang University, Nanchang 330031, China; Jiangxi Poyang Lake Wetland Conservation and Restoration National Permanent Scientific Research Base, National Ecosystem Research Station of Jiangxi Poyang Lake Wetland, Nanchang University, Nanchang 330031, China; Key Laboratory of Poyang Lake Environment and Resource Utilization, Ministry of Education, Nanchang University, Nanchang 330031, China; Jiangxi Institute of Ecological Civilization, School of Resources and Environment, Nanchang University, Nanchang 330031, China.
| | - Hong Yang
- Department of Geography and Environmental Science, University of Reading, Reading RG6 6AB, UK
| | - Jörg Rinklebe
- University of Wuppertal, School of Architecture and Civil Engineering, Institute of Foundation Engineering, Water and Waste Management, Laboratory of Soil and Groundwater Management, Pauluskirchstraße 7, 42285 Wuppertal, Germany; Department of Environment, Energy and Geoinformatics, Sejong University, 98 Gunja-Dong, Guangjin-Gu, Seoul 05006, Republic of Korea
| | - Nanthi Bolan
- School of Agriculture and Environment, The UWA Institute of Agriculture, The University of Western Australia, Perth, WA 6001, Australia
| | - Qiwu Hu
- School of Geography and Environment, Jiangxi Normal University, Nanchang 330022, China
| | - Xinyun Huang
- Jiangxi Province Key Laboratory of Watershed Ecosystem Change and Biodiversity, Center for Watershed Ecology, Institute of Life Science and School of Life Science, Nanchang University, Nanchang 330031, China
| | - Xiuting Wen
- Jiangxi Institute of Ecological Civilization, School of Resources and Environment, Nanchang University, Nanchang 330031, China
| | - Bofu Zheng
- Jiangxi Institute of Ecological Civilization, School of Resources and Environment, Nanchang University, Nanchang 330031, China
| | - Lei Shi
- Jiangxi Institute of Ecological Civilization, School of Resources and Environment, Nanchang University, Nanchang 330031, China
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Bao T, Jia G, Xu X. Warming enhances dominance of vascular plants over cryptogams across northern wetlands. GLOBAL CHANGE BIOLOGY 2022; 28:4097-4109. [PMID: 35364612 DOI: 10.1111/gcb.16182] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Revised: 01/13/2022] [Accepted: 03/26/2022] [Indexed: 06/14/2023]
Abstract
Climate warming causes profound effects on structure and function of wetland ecosystem, thus affecting regional and global hydrological cycles and carbon budgets. However, how wetland plants respond to warming is still poorly understood. Here, we synthesized observations from 273 independent sites to explore responses of northern wetland plants to warming. Our results show that warming enhances biomass accumulation for vascular plants including shrubs and graminoids, whereas it reduces biomass accumulation for cryptogams including moss and lichen. This divergent response of vascular plants and cryptogams is particularly pronounced in the high latitudes where permafrost prevails. As warming continues, this divergent response is amplified, however, the reduction in cryptogams is more drastic. Warming leads to declined surface soil moisture and lowered water table, thereby shifting wetlands from a wet system dominated by cryptogams to a drier system with increased cover of vascular plants. Under a high-emission scenario of Shared Socioeconomic Pathways (SSP5), a 4.7-5.1°C mean global temperature rise will cause more than fivefold loss of cryptogams compared with current climate. As cryptogams are largely concentrated at northern high latitudes, where warming will likely be greater than the projected global mean, modification in wetland plant composition and major reduction in cryptogams are expected to occur even much earlier than 2100.
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Affiliation(s)
- Tao Bao
- Key Laboratory of Regional Climate-Environment for Temperate East Asia, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, China
| | - Gensuo Jia
- Key Laboratory of Regional Climate-Environment for Temperate East Asia, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, China
| | - Xiyan Xu
- Key Laboratory of Regional Climate-Environment for Temperate East Asia, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, China
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30
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Huebner DC, Buchwal A, Bret‐Harte MS. Retrogressive thaw slumps in the Alaskan Low Arctic may influence tundra shrub growth more strongly than climate. Ecosphere 2022. [DOI: 10.1002/ecs2.4106] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Affiliation(s)
- Diane C. Huebner
- Institute of Arctic Biology/Department of Biology and Wildlife University of Alaska Fairbanks Fairbanks Alaska USA
| | - Agata Buchwal
- Institute of Geoecology and Geoinformation Adam Mickiewicz University Poznań Poland
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Chételat J, McKinney MA, Amyot M, Dastoor A, Douglas TA, Heimbürger-Boavida LE, Kirk J, Kahilainen KK, Outridge PM, Pelletier N, Skov H, St Pierre K, Vuorenmaa J, Wang F. Climate change and mercury in the Arctic: Abiotic interactions. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 824:153715. [PMID: 35149079 DOI: 10.1016/j.scitotenv.2022.153715] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2021] [Revised: 02/02/2022] [Accepted: 02/03/2022] [Indexed: 06/14/2023]
Abstract
Dramatic environmental shifts are occuring throughout the Arctic from climate change, with consequences for the cycling of mercury (Hg). This review summarizes the latest science on how climate change is influencing Hg transport and biogeochemical cycling in Arctic terrestrial, freshwater and marine ecosystems. As environmental changes in the Arctic continue to accelerate, a clearer picture is emerging of the profound shifts in the climate and cryosphere, and their connections to Hg cycling. Modeling results suggest climate influences seasonal and interannual variability of atmospheric Hg deposition. The clearest evidence of current climate change effects is for Hg transport from terrestrial catchments, where widespread permafrost thaw, glacier melt and coastal erosion are increasing the export of Hg to downstream environments. Recent estimates suggest Arctic permafrost is a large global reservoir of Hg, which is vulnerable to degradation with climate warming, although the fate of permafrost soil Hg is unclear. The increasing development of thermokarst features, the formation and expansion of thaw lakes, and increased soil erosion in terrestrial landscapes are increasing river transport of particulate-bound Hg and altering conditions for aquatic Hg transformations. Greater organic matter transport may also be influencing the downstream transport and fate of Hg. More severe and frequent wildfires within the Arctic and across boreal regions may be contributing to the atmospheric pool of Hg. Climate change influences on Hg biogeochemical cycling remain poorly understood. Seasonal evasion and retention of inorganic Hg may be altered by reduced sea-ice cover and higher chloride content in snow. Experimental evidence indicates warmer temperatures enhance methylmercury production in ocean and lake sediments as well as in tundra soils. Improved geographic coverage of measurements and modeling approaches are needed to better evaluate net effects of climate change and long-term implications for Hg contamination in the Arctic.
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Affiliation(s)
- John Chételat
- Environment and Climate Change Canada, Ecotoxicology and Wildlife Health Division, National Wildlife Research Centre, Ottawa, ON K1A 0H3, Canada.
| | - Melissa A McKinney
- Department of Natural Resource Sciences, McGill University, Sainte-Anne-de-Bellevue, QC H9X 3V9, Canada
| | - Marc Amyot
- Groupe de recherche interuniversitaire en limnologie (GRIL), Département de sciences biologiques, Complexe des Sciences, Montréal, QC H2V 0B3, Canada
| | - Ashu Dastoor
- Environment and Climate Change Canada, Air Quality Research Division, Dorval, QC H9P 1J3, Canada
| | - Thomas A Douglas
- U.S. Army Cold Regions Research and Engineering Laboratory, Fort Wainwright, AK 99709, USA
| | - Lars-Eric Heimbürger-Boavida
- Aix Marseille Université, CNRS/INSU, Université de Toulon, IRD, Mediterranean Institute of Oceanography (MIO) UM 110, Marseille, France
| | - Jane Kirk
- Environment and Climate Change Canada, Aquatic Contaminants Research Division, Burlington, ON L7S 1A1, Canada
| | - Kimmo K Kahilainen
- Lammi Biological Station, University of Helsinki, Pääjärventie 320, FI-16900 Lammi, Finland
| | - Peter M Outridge
- Geological Survey of Canada, Natural Resources Canada, Ottawa, ON K1A 0E8, Canada
| | - Nicolas Pelletier
- Geography and Environmental Studies, Carleton University, Ottawa, ON K1S 5B6, Canada
| | - Henrik Skov
- Department of Environmental Science, iClimate, Aarhus University, Frederiksborgvej 399, 4000 Roskilde, Denmark
| | - Kyra St Pierre
- Institute for the Oceans and Fisheries, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Jussi Vuorenmaa
- Finnish Environment Institute (SYKE), Latokartanonkaari 11, FI-00790 Helsinki, Finland
| | - Feiyue Wang
- Centre for Earth Observation Sciences (CEOS), Dept. of Environment and Geography, University of Manitoba, Winnipeg, MB R3T 2N2, Canada
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32
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Ren Z, Zhang Y, Li X, Zhang C. Biogeography of Micro-Eukaryotic Communities in Sediment of Thermokarst Lakes Are Jointly Controlled by Spatial, Climatic, and Physicochemical Factors Across the Qinghai-Tibet Plateau. Front Ecol Evol 2022. [DOI: 10.3389/fevo.2022.901107] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Thermokarst lakes are formed following ice-rich permafrost thaw and widely distribute in the cold regions with high latitude and elevation. However, the micro-eukaryotic communities (MECs) in thermokarst lakes are not well studied. Employing 18S rRNA gene sequencing, we assessed the biogeography of MECs and their driving factors in sediments of thermokarst lakes across the Qinghai-Tibet Plateau (QTP). Results showed that Diatom, Gastrotricha, Nematozoa, Ciliophora, and Cercozoa were dominant lineages in relative abundance and OTU richness. MECs varied substantially across the lakes in terms of diversity and composition. Structural equation modeling and mantel test showed that both OTU richness and community structure of MECs had close relationships with spatial factors, climatic factors, and sediment properties, particularly with latitude, mean annual precipitation, pH, as well as nutrient concentrations and stoichiometric ratios. Moreover, different groups of microbial eukaryotes (taxonomic groups and co-occurrence modules) responded differentially to the measured environmental variables. The results suggested that the biogeography of sediment MECs of thermokarst lakes on the QTP were jointly controlled by spatial and climatic factors as well as sediment properties. This study provides the first view of the composition, diversity, and underlying drivers of MECs dynamic in surface sediments of thermokarst lakes across the QTP.
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33
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Zhang Y, Xie C, Wu T, Zhao L, Wu J, Wu X, Li R, Hu G, Liu G, Wang W, Yang G. New permafrost is forming on the exposed bottom of Zonag Lake on the Qinghai-Tibet Plateau. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 815:152879. [PMID: 34995596 DOI: 10.1016/j.scitotenv.2021.152879] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Revised: 12/29/2021] [Accepted: 12/30/2021] [Indexed: 06/14/2023]
Abstract
Most lakes on the Qinghai-Tibet Plateau have expanded in recent years. Zonag Lake, a critical habitat for Tibetan antelopes in the continuous permafrost zone, burst and overflowed after several years of expansion, resulting in a reduction of approximately 100 km2 in the lake area. Observations have revealed new permafrost is forming on the exposed bottom, accompanied by various periglacial landscapes. The permafrost aggradation on the exposed bottom is rapid, and the permafrost base reached 4.9 m, 5.4 m, and 5.7 m in the first three years, respectively. In this study, the future changes and influencing factors of recently formed permafrost are simulated using a one-dimensional finite element model of heat flow. The simulated results indicate that the permafrost on the exposed bottom is likely to continue to develop, appearing first quick back slow trend. Besides the surface temperature, the annual amplitude is also an important factor in affecting the aggradation of permafrost. The unidirectional permafrost aggradation in the study area is different from the bidirectional permafrost aggradation on the closed taliks around the Arctic. Additionally, snow cover and vegetation are two important factors influencing the future development of permafrost on the exposed lake bottom.
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Affiliation(s)
- Yuxin Zhang
- Cryosphere Research Station on the Qinghai-Tibet Plateau, State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resource, Chinese Academy of Sciences, Lanzhou, Gansu 730000, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Changwei Xie
- Cryosphere Research Station on the Qinghai-Tibet Plateau, State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resource, Chinese Academy of Sciences, Lanzhou, Gansu 730000, China.
| | - Tonghua Wu
- Cryosphere Research Station on the Qinghai-Tibet Plateau, State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resource, Chinese Academy of Sciences, Lanzhou, Gansu 730000, China; Southern Marine Science and Engineering Guangdong Laboratory, Guangzhou 511458, China
| | - Lin Zhao
- School of Geographical Sciences, Nanjing University of Information Science and Technology, Nanjing 210044, China
| | - Jichun Wu
- State Key Laboratory of Frozen Soil Engineering, Northwest Institute of Eco-Environment and Resource, Chinese Academy of Sciences, Lanzhou, Gansu 730000, China
| | - Xiaodong Wu
- Cryosphere Research Station on the Qinghai-Tibet Plateau, State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resource, Chinese Academy of Sciences, Lanzhou, Gansu 730000, China
| | - Ren Li
- Cryosphere Research Station on the Qinghai-Tibet Plateau, State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resource, Chinese Academy of Sciences, Lanzhou, Gansu 730000, China
| | - Guojie Hu
- Cryosphere Research Station on the Qinghai-Tibet Plateau, State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resource, Chinese Academy of Sciences, Lanzhou, Gansu 730000, China
| | - Guangyue Liu
- Cryosphere Research Station on the Qinghai-Tibet Plateau, State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resource, Chinese Academy of Sciences, Lanzhou, Gansu 730000, China
| | - Wu Wang
- Cryosphere Research Station on the Qinghai-Tibet Plateau, State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resource, Chinese Academy of Sciences, Lanzhou, Gansu 730000, China
| | - Guiqian Yang
- Cryosphere Research Station on the Qinghai-Tibet Plateau, State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resource, Chinese Academy of Sciences, Lanzhou, Gansu 730000, China; University of Chinese Academy of Sciences, Beijing 100049, China
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Extremely wet summer events enhance permafrost thaw for multiple years in Siberian tundra. Nat Commun 2022; 13:1556. [PMID: 35322039 PMCID: PMC8943195 DOI: 10.1038/s41467-022-29248-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Accepted: 02/24/2022] [Indexed: 11/09/2022] Open
Abstract
Permafrost thaw can accelerate climate warming by releasing carbon from previously frozen soil in the form of greenhouse gases. Rainfall extremes have been proposed to increase permafrost thaw, but the magnitude and duration of this effect are poorly understood. Here we present empirical evidence showing that one extremely wet summer (+100 mm; 120% increase relative to average June-August rainfall) enhanced thaw depth by up to 35% in a controlled irrigation experiment in an ice-rich Siberian tundra site. The effect persisted over two subsequent summers, demonstrating a carry-over effect of extremely wet summers. Using soil thermal hydrological modelling, we show that rainfall extremes delayed autumn freeze-up and rainfall-induced increases in thaw were most pronounced for warm summers with mid-summer precipitation rainfall extremes. Our results suggest that, with rainfall and temperature both increasing in the Arctic, permafrost will likely degrade and disappear faster than is currently anticipated based on rising air temperatures alone.
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35
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Rapid seafloor changes associated with the degradation of Arctic submarine permafrost. Proc Natl Acad Sci U S A 2022; 119:e2119105119. [PMID: 35286188 PMCID: PMC8944826 DOI: 10.1073/pnas.2119105119] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Temperature increases in Arctic regions have focused attention on permafrost degradation on land, whereas little is known about the dynamics of extensive glacial-age permafrost bodies now submerged under the vast Arctic Continental shelves. Repeated high-resolution bathymetric surveys show that extraordinarily rapid morphologic changes are occurring at the edge of the continental slope of the Canadian Beaufort Sea along what was once the seaward limit of relict Pleistocene permafrost. How widespread similar changes are on the Arctic shelves is unknown, as this is one of the first areas in the Arctic subjected to multiple multibeam bathymetric surveys. Rapid morphologic changes associated with active submarine permafrost thawing may be an important process in sculpturing the seafloor in other submarine permafrost settings. Repeated high-resolution bathymetric surveys of the shelf edge of the Canadian Beaufort Sea during 2- to 9-y-long survey intervals reveal rapid morphological changes. New steep-sided depressions up to 28 m in depth developed, and lateral retreat along scarp faces occurred at multiple sites. These morphological changes appeared between 120-m and 150-m water depth, near the maximum limit of the submerged glacial-age permafrost, and are attributed to permafrost thawing where ascending groundwater is concentrated along the relict permafrost boundary. The groundwater is produced by the regional thawing of the permafrost base due to the shift in the geothermal gradient as a result of the interglacial transgression of the shelf. In contrast, where groundwater discharge is reduced, sediments freeze at the ambient sea bottom temperature of ∼−1.4 °C. The consequent expansion of freezing sediment creates ice-cored topographic highs or pingos, which are particularly abundant adjacent to the discharge area.
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36
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Chen Y, Liu A, Cheng X. Detection of thermokarst lake drainage events in the northern Alaska permafrost region. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 807:150828. [PMID: 34627883 DOI: 10.1016/j.scitotenv.2021.150828] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Revised: 10/02/2021] [Accepted: 10/02/2021] [Indexed: 06/13/2023]
Abstract
The rapidly warming Arctic climate is reducing the stability of near-surface permafrost, and the thawing of ice-rich permafrost causes landscape changes known as thermokarst processes. Growing evidence suggests an increasing trend in the frequency and magnitude of thermokarst lake drainage events, which would significantly alter topography and hydrology, affecting ecosystem stability and carbon cycling. Dynamic monitoring of thermokarst lakes through satellite imagery remains a challenging task, as current temporal trend analysis methods have difficulty in accurately detecting when thermokarst lake drainage events occur. In this study, to improve the detection of time series breakpoints, an advanced temporal segmentation and change detection algorithm developed for forest change detection was, for the first time, transposed to monitor thermokarst lake dynamics. Moreover, to filter out spurious signals caused by fluctuations in lake area, we developed a hybrid algorithm to validate the detected thermokarst lake drainage events at the pixel-level and lake object-level, respectively. The method developed in this study demonstrates its effectiveness in detecting thermokarst lake drainage events in Arctic permafrost ecosystems and the potential to monitor the evolution of thermokarst landscapes using Landsat archive. A time-series analysis of changes in the thermokarst lake region of northern Alaska since 2000 using all available Landsat continuous data was performed on the Google Earth Engine platform. In total, 90 drainage lakes larger than 5 ha in size were detected in our study area, nearly a third of which were almost completely drained. As thermokarst lakes drainage represent hotspots of permafrost degradation, we publicly share information on these drained lakes to help select more targeted sites for costly fieldwork and validation activities. This study provides a basis for understanding and quantifying thermokarst lake dynamics in the Arctic permafrost region, which will contribute to the goal of integrating thermokarst processes into earth system models.
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Affiliation(s)
- Yating Chen
- State Key Laboratory of Remote Sensing Science, College of Global Change and Earth System Science, Beijing Normal University, Beijing 100875, China; Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai 519082, China
| | - Aobo Liu
- State Key Laboratory of Remote Sensing Science, College of Global Change and Earth System Science, Beijing Normal University, Beijing 100875, China; Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai 519082, China
| | - Xiao Cheng
- School of Geospatial Engineering and Science, Sun Yat-sen University, Zhuhai 519082, China; Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai 519082, China.
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Chen Y, Kelly R, Genet H, Lara MJ, Chipman ML, McGuire AD, Hu FS. Resilience and sensitivity of ecosystem carbon stocks to fire-regime change in Alaskan tundra. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 806:151482. [PMID: 34742811 DOI: 10.1016/j.scitotenv.2021.151482] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Revised: 11/02/2021] [Accepted: 11/02/2021] [Indexed: 06/13/2023]
Abstract
Fire disturbance has increased in some tundra ecosystems due to anthropogenic climate change, with important ramifications for terrestrial carbon cycling. Assessment of the potential impact of fire-regime change on tundra carbon stocks requires long-term perspectives because tundra fires have been rare historically. Here we integrated the process-based Dynamic Organic Soil version of the Terrestrial Ecosystem Model with paleo-fire records to evaluate the responses of tundra carbon stocks to changes in fire return interval (FRI). Paleorecords reveal that mean FRIs of tundra ecosystems in Alaska ranged from centennial to millennial timescales (200-6000 years) during the late Quaternary, but projected FRIs by 2100 decrease to a few hundred years to several decades (70-660 years). Our simulations indicate threshold effects of changing FRIs on tundra carbon stocks. Shortening FRI from 5000 to 1000 years results in minimal carbon release (<5%) from Alaskan tundra ecosystems. Rapid carbon stock loss occurs when FRI declines below 800 years trigger sustained mobilization of ancient carbon stocks from permafrost soils. However, substantial spatial heterogeneity in the resilience/sensitivity of tundra carbon stocks to FRI change exists, largely attributable to vegetation types. We identified the carbon stocks in shrub tundra as the most vulnerable to decreasing FRI because shrub tundra stores a large share of carbon in combustible biomass and organic soils. Moreover, our results suggest that ecosystems characterized by large carbon stocks and relatively long FRIs (e.g. Brooks Foothills) may transition towards hotspots of permafrost carbon emission as a response to crossing FRI thresholds in the coming decades. These findings combined imply that fire disturbance may play an increasingly important role in future carbon balance of tundra ecosystems, but the net outcome may be strongly modulated by vegetation composition.
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Affiliation(s)
- Yaping Chen
- Department of Plant Biology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Ryan Kelly
- UNC Health Care System, 1025 Think Place, Morrisville, NC, USA
| | - Hélène Genet
- Institute of Arctic Biology, University of Alaska, Fairbanks, AK, USA
| | - Mark Jason Lara
- Department of Plant Biology, University of Illinois at Urbana-Champaign, Urbana, IL, USA; Department of Geography, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Melissa Lynn Chipman
- Department of Earth and Environmental Sciences, Syracuse University, Syracuse, NY, USA
| | - A David McGuire
- Institute of Arctic Biology, University of Alaska, Fairbanks, AK, USA
| | - Feng Sheng Hu
- Department of Plant Biology, University of Illinois at Urbana-Champaign, Urbana, IL, USA; Department of Geology, University of Illinois at Urbana-Champaign, Urbana, IL, USA; Department of Biology, Washington University in Saint Louis, Saint Louis, MO, USA; Department of Earth and Planetary Sciences, Washington University in Saint Louis, Saint Louis, MO, USA.
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38
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PermaBN: A Bayesian Network framework to help predict permafrost thaw in the Arctic. ECOL INFORM 2022. [DOI: 10.1016/j.ecoinf.2022.101601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Varner RK, Crill PM, Frolking S, McCalley CK, Burke SA, Chanton JP, Holmes ME, Saleska S, Palace MW. Permafrost thaw driven changes in hydrology and vegetation cover increase trace gas emissions and climate forcing in Stordalen Mire from 1970 to 2014. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2022; 380:20210022. [PMID: 34865532 PMCID: PMC8646141 DOI: 10.1098/rsta.2021.0022] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Accepted: 07/13/2021] [Indexed: 06/13/2023]
Abstract
Permafrost thaw increases active layer thickness, changes landscape hydrology and influences vegetation species composition. These changes alter belowground microbial and geochemical processes, affecting production, consumption and net emission rates of climate forcing trace gases. Net carbon dioxide (CO2) and methane (CH4) fluxes determine the radiative forcing contribution from these climate-sensitive ecosystems. Permafrost peatlands may be a mosaic of dry frozen hummocks, semi-thawed or perched sphagnum dominated areas, wet permafrost-free sedge dominated sites and open water ponds. We revisited estimates of climate forcing made for 1970 and 2000 for Stordalen Mire in northern Sweden and found the trend of increasing forcing continued into 2014. The Mire continued to transition from dry permafrost to sedge and open water areas, increasing by 100% and 35%, respectively, over the 45-year period, causing the net radiative forcing of Stordalen Mire to shift from negative to positive. This trend is driven by transitioning vegetation community composition, improved estimates of annual CO2 and CH4 exchange and a 22% increase in the IPCC's 100-year global warming potential (GWP_100) value for CH4. These results indicate that discontinuous permafrost ecosystems, while still remaining a net overall sink of C, can become a positive feedback to climate change on decadal timescales. This article is part of a discussion meeting issue 'Rising methane: is warming feeding warming? (part 2)'.
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Affiliation(s)
- Ruth K. Varner
- Department of Earth Sciences, Oceans and Space, University of New Hampshire, Durham, NH 03824, USA
- Institute for the Study of Earth, Oceans and Space, University of New Hampshire, Durham, NH 03824, USA
- Department of Physical Geography, Stockholm University, Stockholm, Sweden
| | - Patrick M. Crill
- Department of Geological Sciences, Stockholm University, Stockholm, Sweden
- Bolin Centre for Climate Research, Stockholm University, Stockholm, Sweden
| | - Steve Frolking
- Department of Earth Sciences, Oceans and Space, University of New Hampshire, Durham, NH 03824, USA
- Institute for the Study of Earth, Oceans and Space, University of New Hampshire, Durham, NH 03824, USA
| | - Carmody K. McCalley
- Thomas H. Gosnell School of Life Sciences, Rochester Institute of Technology, Rochester, NY 14623, USA
| | - Sophia A. Burke
- Department of Earth Sciences, Oceans and Space, University of New Hampshire, Durham, NH 03824, USA
- Institute for the Study of Earth, Oceans and Space, University of New Hampshire, Durham, NH 03824, USA
| | - Jeffrey P. Chanton
- Department of Earth, Ocean and Atmospheric Science, Florida State University, Tallahassee, FL 32306-4350, USA
| | - M. Elizabeth Holmes
- Division of Science and Math, Tallahassee Community College, 444 Appleyard Drive, Tallahassee, FL 32304, USA
| | - Isogenie Project Coordinators
- Department of Microbiology, The Ohio State University, Columbus, OH 43210, USA
- Centre for Microbiome Research, School of Biomedical Science, Translational Research Institute, Queensland University of Technology, Woolloongabba, QLD 4102, Australia
| | - Scott Saleska
- Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ 85721, USA
| | - Michael W. Palace
- Department of Earth Sciences, Oceans and Space, University of New Hampshire, Durham, NH 03824, USA
- Institute for the Study of Earth, Oceans and Space, University of New Hampshire, Durham, NH 03824, USA
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Towards a Monitoring Approach for Understanding Permafrost Degradation and Linked Subsidence in Arctic Peatlands. REMOTE SENSING 2022. [DOI: 10.3390/rs14030444] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Permafrost thaw resulting from climate warming is threatening to release carbon from high latitude peatlands. The aim of this research was to determine subsidence rates linked to permafrost thaw in sub-Arctic peatlands in Sweden using historical orthophotographic (orthophotos), Unoccupied Aerial Vehicle (UAV), and Interferometric Synthetic Aperture Radar (InSAR) data. The orthophotos showed that the permafrost palsa on the study sites have been contracting in their areal extent, with the greatest rates of loss between 2002 and 2008. The surface motion estimated from differential digital elevation models from the UAV data showed high levels of subsidence (maximum of −25 cm between 2017 and 2020) around the edges of the raised palsa plateaus. The InSAR data analysis showed that raised palsa areas had the greatest subsidence rates, with maximum subsidence rates of 1.5 cm between 2017 and 2020; however, all wetland vegetation types showed subsidence. We suggest that the difference in spatial units associated with each sensor explains parts of the variation in the subsidence levels recorded. We conclude that InSAR was able to identify the areas most at risk of subsidence and that it can be used to investigate subsidence over large spatial extents, whereas UAV data can be used to better understand the dynamics of permafrost degradation at a local level. These findings underpin a monitoring approach for these peatlands.
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41
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Li L, Xue B. Methane emissions from northern lakes under climate change: a review. SN APPLIED SCIENCES 2021. [DOI: 10.1007/s42452-021-04869-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
Abstract
AbstractNorthern lakes are important sources of CH4 in the atmosphere under the background of permafrost thaw and winter warming. We synthesize studies on thermokarst lakes, including various carbon sources for CH4 emission and the influence of thermokarst drainage on carbon emission, to show the evasion potential of ancient carbon that stored in the permafrost and CH4 emission dynamics along with thermokarst lake evolution. Besides, we discuss the lake CH4 dynamics in seasonally ice-covered lakes, especially for under-ice CH4 accumulation and emission during spring ice melt and the possible influential factors for CH4 emission in ice-melt period. We summarize the latest findings and point out that further research should be conducted to investigate the possibility of abundant ancient carbon emission from thermokarst lakes under climate warming and quantify the contribution of ice-melt CH4 emission from northern lakes on a large scale.
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Chen Y, Liu A, Cheng X. Vegetation grows more luxuriantly in Arctic permafrost drained lake basins. GLOBAL CHANGE BIOLOGY 2021; 27:5865-5876. [PMID: 34411382 PMCID: PMC9291482 DOI: 10.1111/gcb.15853] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Accepted: 08/15/2021] [Indexed: 05/05/2023]
Abstract
As Arctic warming, permafrost thawing, and thermokarst development intensify, increasing evidence suggests that the frequency and magnitude of thermokarst lake drainage events are increasing. Presently, we lack a quantitative understanding of vegetation dynamics in drained lake basins, which is necessary to assess the extent to which plant growth in thawing ecosystems will offset the carbon released from permafrost. In this study, continuous satellite observations were used to detect thermokarst lake drainage events in northern Alaska over the past 20 years, and an advanced temporal segmentation and change detection algorithm allowed us to determine the year of drainage for each lake. Quantitative analysis showed that the greenness (normalized difference vegetation index [NDVI]) of tundra vegetation growing on wet and nutrient-rich lake sediments increased approximately 10 times faster than that of the peripheral vegetation. It takes approximately 5 years (4-6 years for the 25%-75% range) for the drainage lake area to reach the greenness level of the peripheral vegetation. Eventually, the NDVI values of the drained lake basins were 0.15 (or 25%) higher than those of the surrounding areas. In addition, we found less lush vegetation in the floodplain drained lake basins, possibly due to water logging. We further explored the key environmental drivers affecting vegetation dynamics in and around the drained lake basins. The results showed that our multivariate regression model well simulated the growth dynamics of the drainage lake ecosystem ( Radj2=.73 , p < .001) and peripheral vegetation ( Radj2=.68 , p < .001). Among climate variables, moisture variables were more influential than temperature variables, indicating that vegetation growth in this area is susceptible to water stress. Our study provides valuable information for better modeling of vegetation dynamics in thermokarst lake areas and provides new insights into Arctic greening and carbon balance studies as thermokarst lake drainage intensifies.
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Affiliation(s)
- Yating Chen
- State Key Laboratory of Remote Sensing Science, and College of Global Change and Earth System ScienceBeijing Normal UniversityBeijingChina
- School of Geospatial Engineering and ScienceSun Yat‐Sen UniversityZhuhaiChina
| | - Aobo Liu
- State Key Laboratory of Remote Sensing Science, and College of Global Change and Earth System ScienceBeijing Normal UniversityBeijingChina
- School of Geospatial Engineering and ScienceSun Yat‐Sen UniversityZhuhaiChina
| | - Xiao Cheng
- School of Geospatial Engineering and ScienceSun Yat‐Sen UniversityZhuhaiChina
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43
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Impacts of Permafrost Degradation on Carbon Stocks and Emissions under a Warming Climate: A Review. ATMOSPHERE 2021. [DOI: 10.3390/atmos12111425] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
A huge amount of carbon (C) is stored in permafrost regions. Climate warming and permafrost degradation induce gradual and abrupt carbon emissions into both the atmosphere and hydrosphere. In this paper, we review and synthesize recent advances in studies on carbon stocks in permafrost regions, biodegradability of permafrost organic carbon (POC), carbon emissions, and modeling/projecting permafrost carbon feedback to climate warming. The results showed that: (1) A large amount of organic carbon (1460–1600 PgC) is stored in permafrost regions, while there are large uncertainties in the estimation of carbon pools in subsea permafrost and in clathrates in terrestrial permafrost regions and offshore clathrate reservoirs; (2) many studies indicate that carbon pools in Circum-Arctic regions are on the rise despite the increasing release of POC under a warming climate, because of enhancing carbon uptake of boreal and arctic ecosystems; however, some ecosystem model studies indicate otherwise, that the permafrost carbon pool tends to decline as a result of conversion of permafrost regions from atmospheric sink to source under a warming climate; (3) multiple environmental factors affect the decomposability of POC, including ground hydrothermal regimes, carbon/nitrogen (C/N) ratio, organic carbon contents, and microbial communities, among others; and (4) however, results from modeling and projecting studies on the feedbacks of POC to climate warming indicate no conclusive or substantial acceleration of climate warming from POC emission and permafrost degradation over the 21st century. These projections may potentially underestimate the POC feedbacks to climate warming if abrupt POC emissions are not taken into account. We advise that studies on permafrost carbon feedbacks to climate warming should also focus more on the carbon feedbacks from the rapid permafrost degradation, such as thermokarst processes, gas hydrate destabilization, and wildfire-induced permafrost degradation. More attention should be paid to carbon emissions from aquatic systems because of their roles in channeling POC release and their significant methane release potentials.
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Heffernan L, Jassey VEJ, Frederickson M, MacKenzie MD, Olefeldt D. Constraints on potential enzyme activities in thermokarst bogs: Implications for the carbon balance of peatlands following thaw. GLOBAL CHANGE BIOLOGY 2021; 27:4711-4726. [PMID: 34164885 DOI: 10.1111/gcb.15758] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Revised: 05/04/2021] [Accepted: 06/15/2021] [Indexed: 06/13/2023]
Abstract
Northern peatlands store a globally significant amount of soil organic carbon, much of it found in rapidly thawing permafrost. Permafrost thaw in peatlands often leads to the development and expansion of thermokarst bogs, where microbial activity will determine the stability of the carbon storage and the release of greenhouse gases. In this study, we compared potential enzyme activities between young (thawed ~30 years ago) and mature (~200 years) thermokarst bogs, for both shallow and deep peat layers. We found very low potential enzyme activities in deep peat layers, with no differences between the young and mature bogs. Peat quality at depth was found to be highly humified (FTIR analysis) in both the young and mature bogs. This suggests that deep, old peat was largely stable following permafrost thaw, without a rapid pulse of decomposition during the young bog stage. For near-surface peat, we found significantly higher potential enzyme activities in the young bog than in the mature-associated with differences in peat quality derived from different Sphagnum species. A laboratory incubation of near-surface peat showed that differences in potential enzyme activity were primarily influenced by peat type rather than oxygen availability. This suggested that the young bog can have higher rates of near-surface decomposition despite being substantially wetter than the mature bog. Overall, our study shows that peat properties are the dominant constraint on potential enzyme activity and that peatland site development (successional pathways and permafrost history) through its influence on peat type and chemistry is likely to determine peat decomposition following permafrost thaw.
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Affiliation(s)
- Liam Heffernan
- Department of Renewable Resources, University of Alberta, Edmonton, AB, Canada
| | - Vincent E J Jassey
- Laboratorie d'Ecologie Fonctionelle et Envrionnement, Université de Toulouse, CNRS, Toulouse, France
| | - Maya Frederickson
- Department of Renewable Resources, University of Alberta, Edmonton, AB, Canada
| | - M Derek MacKenzie
- Department of Renewable Resources, University of Alberta, Edmonton, AB, Canada
| | - David Olefeldt
- Department of Renewable Resources, University of Alberta, Edmonton, AB, Canada
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45
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Kwon MJ, Tripathi BM, Göckede M, Shin SC, Myeong NR, Lee YK, Kim M. Disproportionate microbial responses to decadal drainage on a Siberian floodplain. GLOBAL CHANGE BIOLOGY 2021; 27:5124-5140. [PMID: 34216067 DOI: 10.1111/gcb.15785] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Accepted: 06/11/2021] [Indexed: 06/13/2023]
Abstract
Permafrost thaw induces soil hydrological changes which in turn affects carbon cycle processes in the Arctic terrestrial ecosystems. However, hydrological impacts of thawing permafrost on microbial processes and greenhouse gas (GHG) dynamics are poorly understood. This study examined changes in microbial communities using gene and genome-centric metagenomics on an Arctic floodplain subject to decadal drainage, and linked them to CO2 and CH4 flux and soil chemistry. Decadal drainage led to significant changes in the abundance, taxonomy, and functional potential of microbial communities, and these modifications well explained the changes in CO2 and CH4 fluxes between ecosystem and atmosphere-increased fungal abundances potentially increased net CO2 emission rates and highly reduced CH4 emissions in drained sites corroborated the marked decrease in the abundance of methanogens and methanotrophs. Interestingly, various microbial taxa disproportionately responded to drainage: Methanoregula, one of the key players in methanogenesis under saturated conditions, almost disappeared, and also Methylococcales methanotrophs were markedly reduced in response to drainage. Seven novel methanogen population genomes were recovered, and the metabolic reconstruction of highly correlated population genomes revealed novel syntrophic relationships between methanogenic archaea and syntrophic partners. These results provide a mechanistic view of microbial processes regulating GHG dynamics in the terrestrial carbon cycle, and disproportionate microbial responses to long-term drainage provide key information for understanding the effects of warming-induced soil drying on microbial processes in Arctic wetland ecosystems.
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Affiliation(s)
- Min Jung Kwon
- Korea Polar Research Institute, Incheon, Republic of Korea
| | | | | | | | - Nu Ri Myeong
- Korea Polar Research Institute, Incheon, Republic of Korea
| | - Yoo Kyung Lee
- Korea Polar Research Institute, Incheon, Republic of Korea
| | - Mincheol Kim
- Korea Polar Research Institute, Incheon, Republic of Korea
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46
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Tanentzap AJ, Burd K, Kuhn M, Estop-Aragonés C, Tank SE, Olefeldt D. Aged soils contribute little to contemporary carbon cycling downstream of thawing permafrost peatlands. GLOBAL CHANGE BIOLOGY 2021; 27:5368-5382. [PMID: 34157185 DOI: 10.1111/gcb.15756] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Accepted: 06/10/2021] [Indexed: 06/13/2023]
Abstract
Vast stores of millennial-aged soil carbon (MSC) in permafrost peatlands risk leaching into the contemporary carbon cycle after thaw caused by climate warming or increased wildfire activity. Here we tracked the export and downstream fate of MSC from two peatland-dominated catchments in subarctic Canada, one of which was recently affected by wildfire. We tested whether thermokarst bog expansion and deepening of seasonally thawed soils due to wildfire increased the contributions of MSC to downstream waters. Despite being available for lateral transport, MSC accounted for ≤6% of dissolved organic carbon (DOC) pools at catchment outlets. Assimilation of MSC into the aquatic food web could not explain its absence at the outlets. Using δ13 C-Δ14 C-δ15 N-δ2 H measurements, we estimated only 7% of consumer biomass came from MSC by direct assimilation and algal recycling of heterotrophic respiration. Recent wildfire that caused seasonally thawed soils to reach twice as deep in one catchment did not change these results. In contrast to many other Arctic ecosystems undergoing climate warming, we suggest waterlogged peatlands will protect against downstream delivery and transformation of MSC after climate- and wildfire-induced permafrost thaw.
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Affiliation(s)
- Andrew J Tanentzap
- Ecosystems and Global Change Group, Department of Plant Sciences, University of Cambridge, Cambridge, UK
| | - Katheryn Burd
- Department of Renewable Resources, University of Alberta, Edmonton, AB, Canada
| | - McKenzie Kuhn
- Department of Renewable Resources, University of Alberta, Edmonton, AB, Canada
| | | | - Suzanne E Tank
- Department of Biological Sciences, University of Alberta, Edmonton, AB, Canada
| | - David Olefeldt
- Department of Renewable Resources, University of Alberta, Edmonton, AB, Canada
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47
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Standen KM, Baltzer JL. Permafrost condition determines plant community composition and community-level foliar functional traits in a boreal peatland. Ecol Evol 2021; 11:10133-10146. [PMID: 34367564 PMCID: PMC8328418 DOI: 10.1002/ece3.7818] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 04/23/2021] [Accepted: 05/28/2021] [Indexed: 11/05/2022] Open
Abstract
Boreal peatlands are critical ecosystems globally because they house 30%-40% of terrestrial carbon (C), much of which is stored in permafrost soil vulnerable to climate warming-induced thaw. Permafrost thaw leads to thickening of the active (seasonally thawed) layer and alters nutrient and light availability. These physical changes may influence community-level plant functional traits through intraspecific trait variation and/or species turnover. As permafrost thaw is expected to cause an efflux of carbon dioxide (CO2) and methane (CH4) from the soil to the atmosphere, it is important to understand thaw-induced changes in plant community productivity to evaluate whether these changes may offset some of the anticipated increases in C emissions. To this end, we collected vascular plant community composition and foliar functional trait data along gradients in aboveground tree biomass and active layer thickness (ALT) in a rapidly thawing boreal peatland, with the expectation that changes in above- and belowground conditions are indicative of altered resource availability. We aimed to determine whether community-level traits vary across these gradients, and whether these changes are dominated by intraspecific trait variation, species turnover, or both. Our results highlight that variability in community-level traits was largely attributable to species turnover and that both community composition and traits were predominantly driven by ALT. Specifically, thicker active layers associated with permafrost-free peatlands (i.e., bogs and fens) shifted community composition from slower-growing evergreen shrubs to faster-growing graminoids and forbs with a corresponding shift toward more productive trait values. The results from this rapidly thawing peatland suggest that continued warming-induced permafrost thaw and thermokarst development alter plant community composition and community-level traits and thus ecosystem productivity. Increased productivity may help to mitigate anticipated CO2 efflux from thawing permafrost, at least in the short term, though this response may be swamped by increase CH4 release.
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48
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Bao T, Jia G, Xu X. Wetland Heterogeneity Determines Methane Emissions: A Pan-Arctic Synthesis. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:10152-10163. [PMID: 34229435 DOI: 10.1021/acs.est.1c01616] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Methane (CH4) emissions from pan-Arctic wetlands provide a potential positive feedback to global warming. However, the differences in CH4 emissions across wetland types in these regions have not been well understood. We synthesized approximately 9000 static chamber CH4 measurements during the growing season from 83 sites across pan-Arctic regions. We highlighted spatial variations of CH4 emissions corresponding to environmental heterogeneity across wetland types. CH4 emission is the highest in fens, followed by marshes, bogs, and the lowest in swamps. This gradient is controlled by the water table, soil temperature, and dominant plant functional types and their interactions. The water table position for maximum CH4 emission is below, close to, and above the ground surface in bogs, marshes/fens, and swamps, respectively. The temperature sensitivity (Q10) of CH4 emissions varied among different wetland types, ranging from the lowest in swamps to the highest in fens. The interactive impact of temperature and the water table positions on CH4 emissions are regulated with dominant plant functional types. CH4 emissions from wetlands dominated by vascular plants rely more on species composition than that dominated by non-vascular plants. Wetlands with greater abundance of graminoids (e.g., fens) have higher CH4 emissions than tree-dominated wetlands (e.g., swamps). This synthesis emphasizes the role of wetland heterogeneity in determining the strength of CH4 emissions.
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Affiliation(s)
- Tao Bao
- Key Laboratory of Regional Climate-Environment for Temperate East Asia, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China
| | - Gensuo Jia
- Key Laboratory of Regional Climate-Environment for Temperate East Asia, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China
| | - Xiyan Xu
- Key Laboratory of Regional Climate-Environment for Temperate East Asia, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China
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Remote Sensing-Based Statistical Approach for Defining Drained Lake Basins in a Continuous Permafrost Region, North Slope of Alaska. REMOTE SENSING 2021. [DOI: 10.3390/rs13132539] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Lake formation and drainage are pervasive phenomena in permafrost regions. Drained lake basins (DLBs) are often the most common landforms in lowland permafrost regions in the Arctic (50% to 75% of the landscape). However, detailed assessments of DLB distribution and abundance are limited. In this study, we present a novel and scalable remote sensing-based approach to identifying DLBs in lowland permafrost regions, using the North Slope of Alaska as a case study. We validated this first North Slope-wide DLB data product against several previously published sub-regional scale datasets and manually classified points. The study area covered >71,000 km2, including a >39,000 km2 area not previously covered in existing DLB datasets. Our approach used Landsat-8 multispectral imagery and ArcticDEM data to derive a pixel-by-pixel statistical assessment of likelihood of DLB occurrence in sub-regions with different permafrost and periglacial landscape conditions, as well as to quantify aerial coverage of DLBs on the North Slope of Alaska. The results were consistent with previously published regional DLB datasets (up to 87% agreement) and showed high agreement with manually classified random points (64.4–95.5% for DLB and 83.2–95.4% for non-DLB areas). Validation of the remote sensing-based statistical approach on the North Slope of Alaska indicated that it may be possible to extend this methodology to conduct a comprehensive assessment of DLBs in pan-Arctic lowland permafrost regions. Better resolution of the spatial distribution of DLBs in lowland permafrost regions is important for quantitative studies on landscape diversity, wildlife habitat, permafrost, hydrology, geotechnical conditions, and high-latitude carbon cycling.
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50
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Spatial Analyses and Susceptibility Modeling of Thermokarst Lakes in Permafrost Landscapes along the Qinghai–Tibet Engineering Corridor. REMOTE SENSING 2021. [DOI: 10.3390/rs13101974] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Thermokarst lakes (TLs) caused by the thaw of massive ground ice in ice-rich permafrost landscapes are increasing and have strong impacts on the hydro–ecological environment and human infrastructure on the Qinghai–Tibet Plateau (QTP), however, its spatial distribution characteristics and environmental controls have not been underrepresented at the local scale. Here, we analyzed the spatial distribution of small TLs along the Qinghai–Tibet Engineering Corridor (QTEC) based on high-resolution (up to 2.0 m) satellite images. The TLs gathered in the plains and upland plateau and covered 8.3% of the QTEC land. We deployed a random-frost method to investigate the suitable environmental conditions for TLs. Climate including summer rainfall and the air temperature was the most important factor controlling the TL distribution, followed by topography and soil characteristics that affected the ground ice content. TL susceptibility was mapped based on the combinations of climate, soil, and topography grid data. On average, around 20% of the QTEC area was in a high to very-high-susceptibility zone that is likely to develop TLs in response to climate change. This study improved the understanding of controlling factors for TL development but also provided insights into the conditions of massive ground ice and was helpful to assess the impacts of climate change on ecosystem processes and engineering design.
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