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Abrupt permafrost thaw drives spatially heterogeneous soil moisture and carbon dioxide fluxes in upland tundra

Journal Article · · Global Change Biology
DOI:https://doi.org/10.1111/gcb.16936· OSTI ID:2000339
 [1];  [2];  [3];  [4];  [5];  [1];  [1];  [1];  [6];  [7];  [8];  [1];  [1];  [9];  [1]
  1. Northern Arizona Univ., Flagstaff, AZ (United States)
  2. Woodwell Climate Research Center, Falmouth, MA (United States)
  3. Univ. of Texas at El Paso, TX (United States)
  4. Univ. of Massachusetts, Amherst, MA (United States)
  5. Univ. of Arkansas, Fayetteville, AR (United States)
  6. Univ. of Alaska, Fairbanks, AK (United States)
  7. Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)
  8. Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
  9. Univ. of Florida, Gainesville, FL (United States)
+ Show Author Affiliations

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. Here, 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.

Research Organization:
Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
Sponsoring Organization:
USDOE Office of Science (SC), Biological and Environmental Research (BER)
Grant/Contract Number:
AC05-00OR22725; SC0006982; SC0014085; SC0020227
OSTI ID:
2000339
Alternate ID(s):
OSTI ID: 2202709
Journal Information:
Global Change Biology, Journal Name: Global Change Biology Journal Issue: 22 Vol. 29; ISSN 1354-1013
Publisher:
WileyCopyright Statement
Country of Publication:
United States
Language:
English

References (52)

Increased wintertime CO 2 loss as a result of sustained tundra warming : Tundra Wintertime CO journal February 2016
Permafrost thaw and soil moisture driving CO 2 and CH 4 release from upland tundra journal March 2015
Tundra is a consistent source of CO 2 at a site with progressive permafrost thaw during 6 years of chamber and eddy covariance measurements : Tundra CO journal June 2017
The Influence of Shallow Taliks on Permafrost Thaw and Active Layer Dynamics in Subarctic Canada journal February 2018
Interannual and Seasonal Patterns of Carbon Dioxide, Water, and Energy Fluxes From Ecotonal and Thermokarst-Impacted Ecosystems on Carbon-Rich Permafrost Soils in Northeastern Siberia: Siberian CO 2 , Water, and Energy Fluxes journal October 2017
Advances in Thermokarst Research: Recent Advances in Research Investigating Thermokarst Processes journal April 2013
Permafrost thaw‐related slope failures in Alaska’s Arctic National Parks, c . 1980–2019 journal January 2021
Physical and ecological changes associated with warming permafrost and thermokarst in Interior Alaska journal July 2009
Permafrost thermal state in the polar Northern Hemisphere during the international polar year 2007-2009: a synthesis journal April 2010
Impact of unusually wet permafrost soil on understory vegetation and CO2 exchange in a larch forest in eastern Siberia journal February 2019
Real-time automatic interpolation of ambient gamma dose rates from the Dutch radioactivity monitoring network journal August 2009
Degradation and stabilization of ice wedges: Implications for assessing risk of thermokarst in northern Alaska journal November 2017
Permafrost Degradation and Ecological Changes Associated with a WarmingClimate in Central Alaska journal March 2001
Abrupt increase in permafrost degradation in Arctic Alaska journal January 2006
Increasing rates of retrogressive thaw slump activity in the Mackenzie Delta region, N.W.T., Canada journal January 2008
Response of CO 2 exchange in a tussock tundra ecosystem to permafrost thaw and thermokarst development journal January 2009
Climate Change Drives Widespread and Rapid Thermokarst Development in Very Cold Permafrost in the Canadian High Arctic journal June 2019
Water Tracks Enhance Water Flow Above Permafrost in Upland Arctic Alaska Hillslopes journal February 2020
Carbon Thaw Rate Doubles When Accounting for Subsidence in a Permafrost Warming Experiment journal June 2020
The Roles of Climate Extremes, Ecological Succession, and Hydrology in Repeated Permafrost Aggradation and Degradation in Fens on the Tanana Flats, Alaska journal November 2020
Tundra Underlain By Thawing Permafrost Persistently Emits Carbon to the Atmosphere Over 15 Years of Measurements journal June 2021
Experimental Soil Warming and Permafrost Thaw Increase CH4 Emissions in an Upland Tundra Ecosystem journal November 2021
High risk of permafrost thaw journal November 2011
The effect of permafrost thaw on old carbon release and net carbon exchange from tundra journal May 2009
Potential carbon emissions dominated by carbon dioxide from thawed permafrost soils journal June 2016
Circumpolar distribution and carbon storage of thermokarst landscapes journal October 2016
Permafrost is warming at a global scale journal January 2019
Carbon release through abrupt permafrost thaw journal February 2020
Permafrost carbon feedbacks threaten global climate goals journal May 2021
Long-term Circumpolar Active Layer Monitoring (CALM) program observations in Northern Alaskan tundra journal July 2021
Abrupt permafrost thaw accelerates carbon dioxide and methane release at a tussock tundra site journal September 2022
Reorganization of vegetation, hydrology and soil carbon after permafrost degradation across heterogeneous boreal landscapes journal July 2013
Permafrost thaw driven changes in hydrology and vegetation cover increase trace gas emissions and climate forcing in Stordalen Mire from 1970 to 2014
  • Varner, Ruth K.; Crill, Patrick M.; Frolking, Steve
  • Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, Vol. 380, Issue 2215 https://doi.org/10.1098/rsta.2021.0022
journal December 2021
Below-ground plant traits influence tundra plant acquisition of newly thawed permafrost nitrogen journal September 2018
Thawing permafrost increases old soil and autotrophic respiration in tundra: Partitioning ecosystem respiration using δ 13 C and ∆ 14 C journal November 2012
Net ecosystem exchange of CO 2 with rapidly changing high Arctic landscapes journal December 2015
Permafrost collapse alters soil carbon stocks, respiration, CH 4 , and N 2 O in upland tundra journal November 2015
Thermokarst rates intensify due to climate change and forest fragmentation in an Alaskan boreal forest lowland journal January 2016
Nitrogen availability increases in a tundra ecosystem during five years of experimental permafrost thaw journal February 2016
Nonlinear CO 2 flux response to 7 years of experimentally induced permafrost thaw journal March 2017
Winter snow and spring temperature have differential effects on vegetation phenology and productivity across Arctic plant communities journal January 2021
Pan‐Arctic soil moisture control on tundra carbon sequestration and plant productivity journal November 2022
Spatial heterogeneity and environmental predictors of permafrost region soil organic carbon stocks journal February 2021
Permafrost and Climate Change: Carbon Cycle Feedbacks From the Warming Arctic journal October 2022
Balancing the Global Carbon Budget journal May 2007
Ecological Response to Permafrost Thaw and Consequences for Local and Global Ecosystem Services journal November 2018
Effects of Soil Moisture on the Responses of Soil Temperatures to Climate Change in Cold Regions journal May 2013
Vulnerability of Permafrost Carbon to Climate Change: Implications for the Global Carbon Cycle journal September 2008
Welcome to the Tidyverse journal November 2019
Hydrologic Impacts of Thawing Permafrost—A Review journal January 2016
Geomorphological and Climatic Drivers of Thermokarst Lake Area Increase Trend (1999–2018) in the Kolyma Lowland Yedoma Region, North-Eastern Siberia journal January 2021
Estimated stocks of circumpolar permafrost carbon with quantified uncertainty ranges and identified data gaps journal January 2014

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54 ENVIRONMENTAL SCIENCES
Arctic
abrupt thaw
carbon dioxide
carbon flux
permafrost
soil moisture
thermokarst