Article
Environmental Sciences
Emre Babur, Turgay Dindaroglu, Subhan Danish, Max M. Haggblom, Ekrem Ozlu, Gafur Gozukara, Omer Suha Uslu
Summary: This study used interpolation methods to investigate the impact of wildfire on soil organic carbon, microbial biomass carbon concentrations, and soil quality indices in a red pine forest. The results showed that wildfire increased soil carbon stocks, total nitrogen, pH, and qCO2, but decreased microbial biomass carbon and nitrogen.
JOURNAL OF ENVIRONMENTAL MANAGEMENT
(2022)
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
Forestry
Joel Orella, Diana Riza Africa, Catherine Hope Bustillo, Noel Pascua, Conrado Marquez, Henry Adornado, Maricar Aguilos
Summary: This study assessed two contrasting peatland sites in the Philippines to evaluate the impact of disturbances on carbon dynamics. The disturbed site showed significantly lower aboveground biomass and carbon content compared to the undisturbed site. Both sites exhibited an increasing trend of soil carbon content with depth. Additionally, the disturbed site had a higher soil carbon emission rate compared to the undisturbed site.
Article
Environmental Sciences
Tao Bao, Gensuo Jia, Xiyan Xu
Summary: Pristine wetlands have the potential to mitigate climate change, but their role as a greenhouse gas sink or source under warming is uncertain. Observations from 167 sites reveal that wetlands' global warming potential increased by 57% due to a temperature increase of 1.5-2.0 degrees C. The differences in dominant plant types contribute to emission uncertainties. Warming reduces the greenhouse gas sink of pristine wetlands, especially in permafrost areas dominated by vascular plants.
NATURE CLIMATE CHANGE
(2023)
Article
Ecology
Luhong Zhou, Shangshi Liu, Yaning Gu, Linfang Wu, Hang-Wei Hu, Ji-Zheng He
Summary: The impact of fire on above-ground biomass has significant consequences on soil carbon dynamics. The study conducted a global meta-analysis to determine the extent to which fire influenced soil respiration. The findings reveal that fires reduce soil respiration and its components, but the negative effects diminish over time. Fire severity, season, type, climate zones, and biomes moderate the influences of fire on soil respiration.
FUNCTIONAL ECOLOGY
(2023)
Article
Environmental Sciences
Xiaoying Li, Huijun Jin, Ruixia He, Hongwei Wang, Long Sun, Dongliang Luo, Yan Li, Yadong Huang, Xue Yang, Xiaoying Jin, Xiaoli Chang, Lizhong Wang, Changlei Wei, Ze Zhang
Summary: In this study, the authors analyzed the features of permafrost and its influencing factors in a burned area in Northeast China. The results showed significant changes in soil temperatures and active layer thickness due to wildfires. The study also found a decrease in soil organic carbon and total nitrogen content in the burned areas. These findings provide important scientific basis for the protection of boreal forest and wetlands, as well as the ecosystem-protected permafrost under a warming climate.
LAND DEGRADATION & DEVELOPMENT
(2023)
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
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
Multidisciplinary Sciences
Eunji Byun, Fereidoun Rezanezhad, Linden Fairbairn, Stephanie Slowinski, Nathan Basiliko, Jonathan S. Price, William L. Quinton, Pascale Roy-Leveillee, Kara Webster, Philippe Van Cappellen
Summary: The study found that peat accumulation in high latitude wetlands increases with temperature, but standard reaction kinetics failed to fully explain all changes in CO2 production rates, especially below 0 degrees Celsius and after freezing events. Therefore, simple kinetic expressions should not be used to represent CO2 emissions from northern peatlands.
SCIENTIFIC REPORTS
(2021)
Article
Biodiversity Conservation
Maria J. Briones, Mark H. Garnett, Phil Ineson
Summary: This study experimentally addressed the impact of climate warming on terrestrial carbon stores in a UK upland ecosystem. The results showed that increasing temperatures led to a significant shift towards mineralisation of more recent plant-derived carbon inputs, without causing the loss of existing old carbon stores. This suggests that changes in carbon storage in this ecosystem are strongly coupled to plant activities.
GLOBAL CHANGE BIOLOGY
(2021)
Article
Environmental Sciences
C. Beer, A. Runge, G. Grosse, G. Hugelius, C. Knoblauch
Summary: Studies show that retrogressive thaw slumps (RTSs) in Siberia have transformed a previously neutral ecosystem into a significant source of carbon dioxide. These RTSs are releasing approximately 367 +/- 213 gC m-1 a-1 of CO2 annually, which is relatively insignificant on a global scale. However, depending on the future evolution of permafrost thaw and the affected area, these hillslope processes may become a major contributor to additional CO2 emissions.
ENVIRONMENTAL RESEARCH LETTERS
(2023)
Article
Geosciences, Multidisciplinary
Xiaoying Li, Huijun Jin, Ruixia He, Hongwei Wang, Long Sun, Dongliang Luo, Yadong Huang, Yan Li, Xiaoli Chang, Lizhong Wang, Changlei Wei
Summary: Wildfires have a significant impact on vegetation and permafrost in boreal regions. This study investigated the effects of a fire on the ecosystem composition and soil nutrients in the permafrost zones of Northeast China. The results showed that the fire led to ground warming, deepening of the active layer, increased soil moisture content, and changes in vegetation composition. The recovery of vegetation and carbon and nitrogen storage after the fire depended on factors such as the thermal regimes of near-surface permafrost, recovery of vegetation and organic layer, and soil moisture content.
Article
Environmental Sciences
Kristell Hergoualc'h, Jeffrey van Lent, Nelda Dezzeo, Louis V. Verchot, Jan Willem van Groenigen, Mariela Lopez Gonzales, Julio Grandez-Rios
Summary: Tropical peat swamp forests in Peruvian Amazonia, particularly palm swamps, are at risk of degradation which can lead to the transformation of carbon sinks into carbon sources. This study estimated carbon emissions from degraded palm swamps and found that as degradation increases, the capacity of these swamps to sequester carbon decreases and they become high carbon sources. Therefore, sustainable management of these peatlands is crucial.
Article
Soil Science
Nicolas L. Breil, Thierry Lamaze, Vincent Bustillo, Claire-Emmanuelle Marcato-Romain, Benoit Coudert, Solen Queguiner, Nathalie Jarosz-Pelle
Summary: The aim of this study was to understand the impact of the combination of no-till and cover cropping on soil organic carbon (SOC) and soil respiration. The results showed that for soils with high initial SOC contents, there was no significant difference in SOC and respiration between the conservation practices and conventional practices. However, for soils with low initial SOC contents, the conservation practices significantly increased SOC and respiration.
SOIL & TILLAGE RESEARCH
(2023)
Article
Biodiversity Conservation
Chonghua Xu, Xia Xu, Chenghui Ju, Han Y. H. Chen, Brian J. Wilsey, Yiqi Luo, Wei Fan
Summary: The study found that nitrogen addition significantly increased global SOC content, with the increase amplified over time in both organic and mineral soil layers. The increase mainly resulted from enhanced plant carbon input to soils coupled with reduced carbon loss from decomposition.
GLOBAL CHANGE BIOLOGY
(2021)
Review
Ecology
Lorna Harris, Karen Richardson, Kelly A. Bona, Scott J. Davidson, Sarah A. Finkelstein, Michelle Garneau, Jim McLaughlin, Felix Nwaishi, David Olefeldt, Maara Packalen, Nigel T. Roulet, F. Meg Southee, Maria Strack, Kara L. Webster, Sophie L. Wilkinson, Justina C. Ray
Summary: Northern peatlands have cooled the global climate by accumulating large quantities of soil carbon over thousands of years, making them critical for mitigating climate warming. Despite their importance, these peatlands in Canada and globally are facing threats from land-use change and disturbances, highlighting the need for targeted policies to strengthen their management. Insufficient policy safeguards and limited quantification and reporting of peatland greenhouse-gas emissions and removals increase the vulnerability of these important ecosystems.
FRONTIERS IN ECOLOGY AND THE ENVIRONMENT
(2022)
Review
Environmental Sciences
Benjamin W. Abbott, Michael Brown, Joanna C. Carey, Jessica Ernakovich, Jennifer M. Frederick, Laodong Guo, Gustaf Hugelius, Raymond M. Lee, Michael M. Loranty, Robie Macdonald, Paul J. Mann, Susan M. Natali, David Olefeldt, Pam Pearson, Abigail Rec, Martin Robards, Verity G. Salmon, Sayedeh Sara Sayedi, Christina Schadel, Edward A. G. Schuur, Sarah Shakil, Arial J. Shogren, Jens Strauss, Suzanne E. Tank, Brett F. Thornton, Rachael Treharne, Merritt Turetsky, Carolina Voigt, Nancy Wright, Yuanhe Yang, Jay P. Zarnetske, Qiwen Zhang, Scott Zolkos
Summary: Climate change poses a threat to the global permafrost domain, and protecting permafrost ecosystems is crucial for human rights, biosphere integrity, and global climate. Strengthened emissions reduction targets and support for local communities are necessary to preserve intact ecological communities and carbon sinks within the permafrost domain.
FRONTIERS IN ENVIRONMENTAL SCIENCE
(2022)
Article
Soil Science
Zhengfeng An, Edward W. Bork, David Olefeldt, Cameron N. Carlyle, Scott X. Chang
Summary: Increased occurrence of heat wave events can influence soil carbon dynamics and greenhouse gas emissions. This study found that heat wave events led to increased CO2 and N2O emissions in both cropland and forest soils, with a diminishing effect as heat wave frequency increased.
BIOLOGY AND FERTILITY OF SOILS
(2022)
Review
Geosciences, Multidisciplinary
Stephanie N. Wright, Lauren M. Thompson, David Olefeldt, Ryan F. Connon, Olivia A. Carpino, Casey R. Beel, William L. Quinton
Summary: Rising air temperatures, intensifying wildfire activity, and human disturbance are driving rapid permafrost thaw across the subarctic. The Taiga Plains and Taiga Shield ecozones of northwestern Canada have recently experienced significant permafrost thaw, leading to concerns and knowledge gaps in the affected communities. These thaw-induced changes include landcover, hydrology, and water quality, with the main drivers being increased thermokarst wetland extent and enhanced connectivity between surface water and groundwater.
EARTH-SCIENCE REVIEWS
(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)
Article
Environmental Sciences
Cristian Estop-Aragones, Liam Heffernan, Klaus-Holger Knorr, David Olefeldt
Summary: This study investigated the differences in anaerobic soil organic carbon (SOC) mineralization following permafrost thaw in peatlands and the vulnerability of previously-frozen peat. The research found that the rate of SOC mineralization decreased with depth and peat age, but there were no significant differences in mineralization rates between recently-thawed peat and peat thawed 200 years ago. The study suggests that rapid SOC loss following thaw is unlikely.
JOURNAL OF GEOPHYSICAL RESEARCH-BIOGEOSCIENCES
(2022)
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
Ecology
Liam Heffernan, Maria A. Cavaco, Maya P. Bhatia, Cristian Estop-Aragones, Klaus-Holger Knorr, David Olefeldt
Summary: Permafrost thaw in northern peatlands leads to increased methane emissions, and this study investigates the factors responsible and their duration. The researchers found that microbial communities, temperature, and saturated surface conditions enhance methane emissions in young thermokarst bogs. However, these favorable conditions only persist for the initial decades after permafrost thaw.