Recent peat and carbon accumulation on changing permafrost landforms along the Mackenzie River valley, Northwest Territories, Canada

Bibliographic Data

ID15545165
AuthorsPénélope Germain Chartrand (0000-0001-9097-3823, Université du Québec à Montréal, corresponding author), Oliver Sonnentag (0000-0001-9333-9721, Université de Montréal), Nicole K Sanderson (0000-0002-2225-8446), Michelle Garneau (0000-0002-1956-9243, Université du Québec à Montréal)
Year2023
Volume18
Issue9
Pages095002-095002
Publication date2023-07-24
Open AccessYes
TypeARTICLE
VenueEnvironmental Research Letters (JOURNAL)
Journal identifiersISSN: 1748-9326 • E-ISSN: 1748-9326
PublisherIOP Publishing (PUBLISHER • GB)
DOI10.1088/1748-9326/ace9ed
OpenAlexW4385189854
LanguageEN
References cited54

Northwestern Canada is currently warming nearly four times faster than the global average, driving accelerated permafrost thaw and changes to ecosystem vegetation, hydrology and landscape structure across the landscape. While permafrost peatlands constitute a large carbon reservoir, there is no consensus yet on the direction and magnitude of changes to their vulnerable carbon balance. Here, we assessed changes in peatland ecosystems following permafrost thaw at three sites located along a 1000 km long climate and permafrost gradient along the Mackenzie River valley, Canada. Specifically, we examined vegetation succession over the last few decades to evaluate the possible impact of climate warming on peat and carbon accumulation. Results from the palaeoecological analysis of 20 surficial peat cores, supported by robust chronologies, show a return to Sphagnum accumulation since ca. 1980 CE in the sporadic and discontinuous permafrost zones and ca . 2000 CE in the continuous permafrost zone. The average rates of peat and carbon accumulation reached 4 mm yr −1 and 134 g C m −2 yr −1 at the northernmost site in the continuous permafrost zone. In contrast, peat and carbon accumulation reached 3 mm yr −1 and 81 g C m −2 yr −1 , respectively, in the sporadic and discontinuous permafrost zones. This study highlights the need for a net carbon budget that integrates the recent accelerated Sphagnum growth and carbon uptake from the atmosphere to better assess the potential carbon emissions offset following permafrost thaw. High-resolution palaeoecological studies can offer insights into decadal-scale patterns of vegetation and carbon balance changes to improve model predictions of peat climate-carbon cycle feedbacks

Bog · Carbon cycle · Climate change · Earth science · Ecosystem · Geography · Geomorphology · Hydrology (agriculture · Landform · Peat · Permafrost · Physical geography · Soil carbon · Soil water · Sphagnum · Thermokarst · Vegetation (pathology · Climate change and permafrost · Environmental Science · Geology and Paleoclimatology Research · Peatlands and Wetlands Ecology · Ecology · Geology · Oceanography · Soil Science

Tools

Open DOIOpen Access