Article
Biodiversity Conservation
Liam Heffernan, Vincent E. J. Jassey, Maya Frederickson, M. Derek MacKenzie, David Olefeldt
Summary: The study found that deep peat layers have very low potential enzyme activities, with no differences between young and mature bogs. Peat quality at depth was highly humified in both young and mature bogs. Near-surface peat in young bogs showed significantly higher potential enzyme activities compared to mature bogs, influenced by differences in peat quality derived from different Sphagnum species.
GLOBAL CHANGE BIOLOGY
(2021)
Article
Geosciences, Multidisciplinary
Mei Mu, Cuicui Mu, Hebin Liu, Haiteng Chi, Yongji Zhu, Jianguo Shang, Chengyan Fan, Xiaodong Wu, Guofei Zhang
Summary: A study conducted in the northern Qinghai-Tibetan Plateau found that permafrost collapse led to the loss of soil organic carbon and nitrogen, weakening carbon sinks. The study also revealed that soil temperature, moisture, and nutrient availability were the main controlling factors of carbon emissions during permafrost collapse.
Article
Biodiversity Conservation
Lorna I. Harris, David Olefeldt, Nicolas Pelletier, Christian Blodau, Klaus-Holger Knorr, Julie Talbot, Liam Heffernan, Merritt Turetsky
Summary: Rapid permafrost thaw in western Canada is causing net carbon loss and new carbon accumulation in peatlands. Although there are no significant changes to the quality and stability of deep peat following thaw, the exact mechanisms of carbon loss are still uncertain.
GLOBAL CHANGE BIOLOGY
(2023)
Article
Environmental Sciences
M. R. N. Moore, S. E. Tank, M. R. Kurek, M. Taskovic, A. M. McKenna, J. L. J. Smith, S. V. Koklej, R. G. M. Spencer
Summary: The Arctic is experiencing rapid warming, causing the thawing of permafrost and releasing organic carbon. This study found that the thawed permafrost inputs can be observed in streams, with higher concentrations of dissolved organic carbon and lower aromaticity. The unique molecular fingerprints of permafrost inputs can be tracked downstream in the aquatic network.
Article
Biodiversity Conservation
Cuicui Mu, Mei Mu, Xiaodong Wu, Lin Jia, Chenyan Fan, Xiaoqing Peng, Chien-Lu Ping, Qingbai Wu, Cunde Xiao, Jianbao Liu
Summary: This study measured CH4 and CO2 diffusive fluxes in 163 thermokarst lakes in the Qinghai-Tibet Plateau over 3 years, finding that the median carbon emissions were 1440 mg CO2 m(-2) day(-1) and 60 mg CH4 m(-2) day(-1). The diffusive rates of CH4 and CO2 were related to the catchment land cover type, with sediment microbial abundance and hydrochemistry explaining a significant portion of the variance in CH4 emissions. The study highlights the importance of incorporating in situ observation data and considering different emission pathways for predicting future carbon emissions from thermokarst lakes.
GLOBAL CHANGE BIOLOGY
(2023)
Article
Agronomy
Ran Du, Xiaoqing Peng, Kang Wang, Oliver W. Frauenfeld, Cong Chen, Wen Sun, Haodong Jin, Yaohua Zhao, Sijia Peng, Benben Liang
Summary: The study found that the response of peat-rich permafrost in the northeastern Tibetan Plateau to climate change is slower, mainly due to the low thermal conductivity and high soil moisture of peat. The research also showed that the active layer depth of permafrost at the mineral site is 3-12 times that of the peatland site. By 2100, all permafrost at the mineral site will degrade to seasonally frozen ground.
AGRICULTURAL AND FOREST METEOROLOGY
(2021)
Article
Environmental Sciences
Evgeniya Golovatskaya, Liliya Nikonova, Galina Simonova, Daria Kalashnikova
Summary: This study examines the decomposition of litter from Sphagnum fuscum and Eriophorum vaginatum in drained and post-pyrogenic sites over a period of 3 years. The results show that Sph. fuscum decomposes at a slower rate and has a lower transformation rate compared to E. vaginatum. δ C-13 values indicate C-13 enrichment during the decomposition of Sphagnum residues and C-12 enrichment during the decomposition of E. vaginatum.
Article
Environmental Sciences
Penelope Germain Chartrand, Oliver Sonnentag, Nicole K. Sanderson, Michelle Garneau
Summary: Northwestern Canada is warming at an alarming rate, causing permafrost thaw and changes in the ecosystem. A study conducted in the Mackenzie River valley found that peat and carbon accumulation rates have increased since the 1980s and 2000s in different permafrost zones. This highlights the importance of considering the recent growth of mosses and carbon uptake to assess carbon emissions following permafrost thaw.
ENVIRONMENTAL RESEARCH LETTERS
(2023)
Article
Environmental Sciences
Yang Su, Youhua Ran, Guoqing Zhang, Xin Li
Summary: This study utilized remote sensing data to analyze the changes in lake surface area in permafrost regions. The results show an overall increase in lake area, but also indicate that seasonal lake area can both increase and decrease. These changes are most pronounced in low-lying areas, high-density lake regions, and warm permafrost regions, suggesting the significance of thawing or disappearance of permafrost in driving lake changes.
SCIENCE OF THE TOTAL ENVIRONMENT
(2023)
Article
Geosciences, Multidisciplinary
Jing Luo, Fujun Niu, Zhanju Lin, Minghao Liu, Guoan Yin, Zeyong Gao
Summary: This study investigated the changes in thermokarst lakes on the Qinghai-Tibet Plateau using high spatial resolution images. The results showed a significant increase in the number and surface area of thermokarst lakes over the last fifty years, with variations in change among different landform types. The increase in small lakes and expansion of large lakes were the main changes observed, while lake drainage occurred in some gentle slope areas. Climate warming and increased precipitation were identified as the most likely factors driving these changes.
Article
Plant Sciences
Danica Fazekasova, Gabriela Barancikova, Juraj Fazekas, Lenka Stofejova, Jan Halas, Tadeas Litavec, Tibor Liptaj
Summary: This paper presents the results of pedological and phytocoenological research on two different peatlands in Slovakia, focusing on the detailed analysis of chemical parameters, risk elements, and species composition of the vegetation. The study found differences in peat thickness, organic matter quality, soil reaction, nitrogen supply, and plant diversity between the two types of peatlands. The results of the statistical testing confirmed the diversity of the studied peatlands and the different impact of environmental variables on plant diversity.
Article
Environmental Sciences
Kristen L. Manies, Miriam C. Jones, Mark P. Waldrop, Mary-Cathrine Leewis, Christopher Fuller, Robert S. Cornman, Kristen Hoefke
Summary: The study quantified permafrost peat plateau and post-thaw carbon stocks in Interior Alaska, showing that carbon losses due to thaw could be up to 46% of the available carbon, which was more than 50% lower than losses in other Alaskan peatland chronosequences. The difference in carbon loss may be attributed to the process by which permafrost aggraded, with sites forming permafrost at different times experiencing different levels of absolute carbon loss with thaw.
JOURNAL OF GEOPHYSICAL RESEARCH-BIOGEOSCIENCES
(2021)
Article
Environmental Sciences
Xianmin Ke, Yujiao Li, Wei Wang, Fujun Niu, Zeyong Gao
Summary: This study compared the chemical and hydrogeochemical characteristics of lake water and groundwater in a typical thermokarst lake region on the Qinghai-Tibet Plateau, revealing the variations in contribution of permafrost meltwater and precipitation to groundwater and lake water during different stages of active layer melting.
SCIENCE OF THE TOTAL ENVIRONMENT
(2022)
Article
Environmental Sciences
Thomas G. Sim, Graeme T. Swindles, Paul J. Morris, Andy J. Baird, Claire L. Cooper, Angela Gallego-Sala, Dan J. Charman, Thomas P. Roland, Werner Borken, Donal J. Mullan, Marco A. Aquino-Lopez, Mariusz Galka
Summary: Permafrost peatlands in high-latitude regions store significant amounts of soil organic carbon but are now experiencing rapid warming causing permafrost thaw and carbon release. Recent research in northern Sweden shows that different peatlands are responding differently to climate change, with some becoming wetter leading to reduced carbon sequestration while others becoming drier without a clear relationship. Bryophyte-dominated vegetation in these peatlands demonstrates resistance and in some cases, resilience, to climatic and hydrological shifts.
ENVIRONMENTAL RESEARCH LETTERS
(2021)
Article
Environmental Sciences
Mark Torre Jorgenson, Mikhail Kanevskiy, Carl Roland, Kenneth Hill, David Schirokauer, Sarah Stehn, Britta Schroeder, Yuri Shur
Summary: The study found that extreme seasonal weather, ecological succession, fire, and a legacy of earlier geomorphic processes all affect the formation and degradation of permafrost, creating a highly patchy mosaic of ecotypes within boreal peatland ecosystems with widely varying ecological trajectories.
Review
Environmental Sciences
Scott J. Davidson, Emily Daze, Eunji Byun, Dean Hiler, Markus Kangur, Julie Talbot, Sarah A. Finkelstein, Maria Strack
Summary: This study provides a comparative analysis of carbon dynamics in different types of North American swamps, highlighting differences in carbon fluxes, biomass, and net primary productivity. The findings suggest that broad-leaved swamps have the highest methane flux, soil bulk densities, and lowest organic matter contents, while needle-leaved swamps have the highest aboveground biomass and net primary productivity. Despite the abundance of swamps in Canada and the United States, there is a significant lack of studies focused on swamp carbon dynamics.
ENVIRONMENTAL RESEARCH LETTERS
(2022)
Article
Geosciences, Multidisciplinary
Julien Arsenault, Julie Talbot, Lee E. Brown, Joseph Holden, Karla Martinez-Cruz, Armando Sepulveda-Jauregui, Graeme T. Swindles, Maxime Wauthy, Jean-Francois Lapierre
Summary: Research has shown that peatland ponds are distinct from lakes in biogeochemical terms, while thermokarst waterbodies share characteristics with peatland ponds, lakes, or both. Peatland ponds tend to have higher dissolved organic carbon concentrations and acidity than lakes, highlighting their unique role in global biogeochemical cycles.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Water Resources
Dimitre D. Dimitrov, Peter Lafleur, Oliver Sonnentag, Julie Talbot, William L. Quinton
Summary: Simple and robust hydrological modelling is crucial for peat studies. This study shows that near-surface water content can accurately predict water content at any depth and/or water table depth in peat. The model achieved high agreement with observations, demonstrating its potential for large-scale estimation of water content and water table depth.
HYDROLOGICAL SCIENCES JOURNAL
(2022)
Article
Multidisciplinary Sciences
Hui Zhang, Minna Valiranta, Graeme T. Swindles, Marco A. Aquino-Lopez, Donal Mullan, Ning Tan, Matthew Amesbury, Kirill Babeshko, Kunshan Bao, Anatoly Bobrov, Viktor Chernyshov, Marissa A. Davies, Andrei-Cosmin Diaconu, Angelica Feurdean, Sarah A. Finkelstein, Michelle Garneau, Zhengtang Guo, Miriam C. Jones, Martin Kay, Eric S. Klein, Mariusz Lamentowicz, Gabriel Magnan, Katarzyna Marcisz, Natalia Mazei, Yuri Mazei, Richard Payne, Nicolas Pelletier, Sanna R. Piilo, Steve Pratte, Thomas Roland, Damir Saldaev, William Shotyk, Thomas G. Sim, Thomas J. Sloan, Michal Slowinski, Julie Talbot, Liam Taylor, Andrey N. Tsyganov, Sebastian Wetterich, Wei Xing, Yan Zhao
Summary: A recent synthesis study has found that high-latitude peatlands have exhibited complex and highly uncertain ecohydrological dynamics over the past centuries, with 54% of the peatlands drying and 32% wetting. This highlights the importance of understanding the responses of high-latitude peatlands to a warming climate.
NATURE COMMUNICATIONS
(2022)
Article
Limnology
Lauren M. Thompson, McKenzie A. Kuhn, Johanna C. Winder, Lucas P. P. Braga, Ryan H. S. Hutchins, Andrew J. Tanentzap, Vincent L. St. Louis, David Olefeldt
Summary: Permafrost thaw can lead to increased production of neurotoxic methylmercury (MeHg) in northern peatlands. This study examined total mercury (THg) and MeHg concentrations in lakes and streams along a permafrost transect in boreal western Canada. The results showed that peatlands were the primary sources of MeHg, with concentrations increasing in streams with higher levels of aromatic dissolved organic carbon (DOC), iron, and lower pH. The study also found that peatland lakes acted as sinks for MeHg, with lower concentrations compared to streams.
LIMNOLOGY AND OCEANOGRAPHY
(2023)
Article
Limnology
McKenzie A. Kuhn, Megan Schmidt, Liam Heffernan, Joerdis Stuehrenberg, Klaus-Holger Knorr, Cristian Estop-Aragones, Tanja Broder, Regina Gonzalez Moguel, Peter M. J. Douglas, David Olefeldt
Summary: Methane and carbon dioxide emissions from small peatland lakes are sensitive to climate warming and permafrost thaw. A study in boreal western Canada showed that methane emissions from the thaw edge were much higher than the stable lake edge and center, while diffusive methane fluxes did not differ significantly. Radiocarbon analysis of methane bubbles indicated older carbon at the thaw edge. Accounting for these emissions only slightly increased the estimated total lake methane emissions.
LIMNOLOGY AND OCEANOGRAPHY
(2023)
Correction
Environmental Sciences
Scott J. Davidson, Emily Daze, Eunji Byun, Dean Hiler, Markus Kangur, Julie Talbot, Sarah A. Finkelstein, Maria Strack
ENVIRONMENTAL RESEARCH LETTERS
(2023)
Article
Environmental Sciences
Mahmud Hassan, Julie Talbot, Julien Arsenault, Karla Martinez-Cruz, Armando Sepulveda-Jauregui, Jorge Hoyos-Santillan, Jean-Francois Lapierre
Summary: Peatland open-water pools in different regions show coherent patterns of CO2, CH4, and DOM concentrations and compositions, which are driven by geographical and climatic factors such as temperature, precipitation, and vegetation cover. The concentrations of CO2 and CH4 are influenced by morphometry, vegetation cover, and the composition of DOM. In addition, the temporal variations of CO2 and CH4 are further influenced by seasonal changes in DOM composition, dissolved organic carbon and nutrient concentrations, as well as pH and oxygen levels. Geophysical constraints associated with local peat and pool characteristics play a significant role in determining DOM and greenhouse gases concentrations in peatland pools.
GLOBAL BIOGEOCHEMICAL CYCLES
(2023)
Article
Biodiversity Conservation
Julien Arsenault, Julie Talbot, Lee E. Brown, Manuel Helbig, Joseph Holden, Jorge Hoyos-Santillan, Emilie Jolin, Roy Mackenzie, Karla Martinez-Cruz, Armando Sepulveda-Jauregui, Jean-Francois Lapierre
Summary: Peatland pools are dynamic aquatic ecosystems that contribute to biogeochemical cycles, but their response to environmental change is poorly understood. This study analyzed pool biogeochemical data from multiple locations to determine the drivers of carbon, nitrogen, and phosphorus dynamics in peatland pools. Climate and terrain were found to explain variations in pool biogeochemistry, with climate driving spatial differences in dissolved organic carbon concentration. The study also demonstrated the reactivity of peatland pools to local and global environmental change. These findings highlight the importance of understanding and monitoring peatland pool dynamics as potential climate sentinels.
GLOBAL CHANGE BIOLOGY
(2023)
Article
Biodiversity Conservation
Johanna C. Winder, Lucas P. P. Braga, McKenzie A. Kuhn, Lauren M. Thompson, David Olefeldt, Andrew J. Tanentzap
Summary: Northern lakes have a significant impact on the global carbon cycle, and their microbial communities play a crucial role in this process. This study examined how these microbial communities respond to climate warming and found that the loss of permafrost cover and changes in groundwater connectivity had different effects on microbial composition and function. These findings provide insights into the mechanisms behind increases in methane emissions associated with permafrost thaw and highlight the importance of considering both direct and indirect effects of climate warming on aquatic carbon cycling.
GLOBAL CHANGE BIOLOGY
(2023)
Article
Multidisciplinary Sciences
Guibiao Yang, Zhihu Zheng, Benjamin W. Abbott, David Olefeldt, Christian Knoblauch, Yutong Song, Luyao Kang, Shuqi Qin, Yunfeng Peng, Yuanhe Yang
Summary: This study provides insights into methane emissions from thermokarst lakes in high-altitude permafrost regions. The findings show that thermokarst lakes have high methane emissions during the ice-free period, with ebullition being the primary emission pathway. The study also highlights the importance of methanogenic genes in regulating methane fluxes.
NATURE COMMUNICATIONS
(2023)
Article
Environmental Sciences
Christopher Schulze, Oliver Sonnentag, Carolina Voigt, Lauren Thompson, Lona van Delden, Liam Heffernan, Guillermo Hernandez-Ramirez, McKenzie Kuhn, Sisi Lin, David Olefeldt
Summary: The greenhouse gas balance of boreal peatlands in permafrost regions is influenced by climate change, particularly through disturbances like permafrost thaw and wildfire. The study measured monthly fluxes of nitrous oxide (N2O), methane (CH4), and carbon dioxide (CO2) from different sites in western Canada's sporadic and discontinuous permafrost zones. The results showed that disturbance impacts on N2O fluxes varied, with undisturbed peat plateaus acting as N2O sinks, burned plateaus having lower N2O uptake, and thermokarst bogs showing higher N2O uptake following permafrost thaw.
JOURNAL OF GEOPHYSICAL RESEARCH-BIOGEOSCIENCES
(2023)
Article
Biodiversity Conservation
Lorna I. Harris, David Olefeldt, Nicolas Pelletier, Christian Blodau, Klaus-Holger Knorr, Julie Talbot, Liam Heffernan, Merritt Turetsky
Summary: Rapid permafrost thaw in western Canada is causing net carbon loss and new carbon accumulation in peatlands. Although there are no significant changes to the quality and stability of deep peat following thaw, the exact mechanisms of carbon loss are still uncertain.
GLOBAL CHANGE BIOLOGY
(2023)
Article
Environmental Sciences
Ryan H. S. Hutchins, Suzanne E. Tank, David Olefeldt, William L. Quinton, Christopher Spence, Nicole Dion, Samson G. Mengistu
Summary: Wildfires in northern regions are causing changes in water quality, but the effects are relatively small compared to other factors such as climate and watershed characteristics. Variability in stream water chemistry is driven by watershed-specific properties, overshadowing the influence of wildfires. Future impacts on streams are likely more substantially driven by climate change and altered hydrology than increasing wildfire frequency.
JOURNAL OF GEOPHYSICAL RESEARCH-BIOGEOSCIENCES
(2023)
Article
Environmental Sciences
Patrick M. Senga, Julie Talbot, Steeve Bonneville
Summary: The discovery of the world's largest known peat deposit in the Central African Basin calls for a realistic national assessment of peat carbon in the Democratic Republic of Congo (DRC). This study examined the physicochemical properties of two peat deposits in Sud-Kivu Province and estimated their carbon stocks. Land use change has significantly altered the vegetation and carbon accumulation at these sites.