Lower soil moisture and deep soil temperatures in thermokarst features increase old soil carbon loss after 10 years of experimental permafrost warming

© 2020 John Wiley & Sons Ltd.

Détails bibliographiques
Publié dans:Global change biology. - 1999. - 27(2021), 6 vom: 01. März, Seite 1293-1308
Auteur principal: Pegoraro, Elaine F (Auteur)
Autres auteurs: Mauritz, Marguerite E, Ogle, Kiona, Ebert, Christopher H, Schuur, Edward A G
Format: Article en ligne
Langue:English
Publié: 2021
Accès à la collection:Global change biology
Sujets:Journal Article climate change feedback dual-carbon isotope mixing model ecosystem respiration permafrost radiocarbon thermokarst Soil Carbon 7440-44-0
LEADER 01000caa a22002652c 4500
001 NLM31870790X
003 DE-627
005 20250228130816.0
007 cr uuu---uuuuu
008 231225s2021 xx |||||o 00| ||eng c
024 7 |a 10.1111/gcb.15481  |2 doi 
028 5 2 |a pubmed25n1062.xml 
035 |a (DE-627)NLM31870790X 
035 |a (NLM)33305441 
040 |a DE-627  |b ger  |c DE-627  |e rakwb 
041 |a eng 
100 1 |a Pegoraro, Elaine F  |e verfasserin  |4 aut 
245 1 0 |a Lower soil moisture and deep soil temperatures in thermokarst features increase old soil carbon loss after 10 years of experimental permafrost warming 
264 1 |c 2021 
336 |a Text  |b txt  |2 rdacontent 
337 |a ƒaComputermedien  |b c  |2 rdamedia 
338 |a ƒa Online-Ressource  |b cr  |2 rdacarrier 
500 |a Date Completed 21.04.2021 
500 |a Date Revised 21.04.2021 
500 |a published: Print-Electronic 
500 |a Citation Status MEDLINE 
520 |a © 2020 John Wiley & Sons Ltd. 
520 |a Almost half of the global terrestrial soil carbon (C) is stored in the northern circumpolar permafrost region, where air temperatures are increasing two times faster than the global average. As climate warms, permafrost thaws and soil organic matter becomes vulnerable to greater microbial decomposition. Long-term soil warming of ice-rich permafrost can result in thermokarst formation that creates variability in environmental conditions. Consequently, plant and microbial proportional contributions to ecosystem respiration may change in response to long-term soil warming. Natural abundance δ13 C and Δ14 C of aboveground and belowground plant material, and of young and old soil respiration were used to inform a mixing model to partition the contribution of each source to ecosystem respiration fluxes. We employed a hierarchical Bayesian approach that incorporated gross primary productivity and environmental drivers to constrain source contributions. We found that long-term experimental permafrost warming introduced a soil hydrology component that interacted with temperature to affect old soil C respiration. Old soil C loss was suppressed in plots with warmer deep soil temperatures because they tended to be wetter. When soil volumetric water content significantly decreased in 2018 relative to 2016 and 2017, the dominant respiration sources shifted from plant aboveground and young soil respiration to old soil respiration. The proportion of ecosystem respiration from old soil C accounted for up to 39% of ecosystem respiration and represented a 30-fold increase compared to the wet-year average. Our findings show that thermokarst formation may act to moderate microbial decomposition of old soil C when soil is highly saturated. However, when soil moisture decreases, a higher proportion of old soil C is vulnerable to decomposition and can become a large flux to the atmosphere. As permafrost systems continue to change with climate, we must understand the thresholds that may propel these systems from a C sink to a source 
650 4 |a Journal Article 
650 4 |a climate change feedback 
650 4 |a dual-carbon isotope mixing model 
650 4 |a ecosystem respiration 
650 4 |a permafrost 
650 4 |a radiocarbon 
650 4 |a thermokarst 
650 7 |a Soil  |2 NLM 
650 7 |a Carbon  |2 NLM 
650 7 |a 7440-44-0  |2 NLM 
700 1 |a Mauritz, Marguerite E  |e verfasserin  |4 aut 
700 1 |a Ogle, Kiona  |e verfasserin  |4 aut 
700 1 |a Ebert, Christopher H  |e verfasserin  |4 aut 
700 1 |a Schuur, Edward A G  |e verfasserin  |4 aut 
773 0 8 |i Enthalten in  |t Global change biology  |d 1999  |g 27(2021), 6 vom: 01. März, Seite 1293-1308  |w (DE-627)NLM098239996  |x 1365-2486  |7 nnas 
773 1 8 |g volume:27  |g year:2021  |g number:6  |g day:01  |g month:03  |g pages:1293-1308 
856 4 0 |u http://dx.doi.org/10.1111/gcb.15481  |3 Volltext 
912 |a GBV_USEFLAG_A 
912 |a SYSFLAG_A 
912 |a GBV_NLM 
912 |a GBV_ILN_350 
951 |a AR 
952 |d 27  |j 2021  |e 6  |b 01  |c 03  |h 1293-1308