1. Environmental drivers of increased ecosystem respiration in a warming tundra.
- Author
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Maes SL, Dietrich J, Midolo G, Schwieger S, Kummu M, Vandvik V, Aerts R, Althuizen IHJ, Biasi C, Björk RG, Böhner H, Carbognani M, Chiari G, Christiansen CT, Clemmensen KE, Cooper EJ, Cornelissen JHC, Elberling B, Faubert P, Fetcher N, Forte TGW, Gaudard J, Gavazov K, Guan Z, Guðmundsson J, Gya R, Hallin S, Hansen BB, Haugum SV, He JS, Hicks Pries C, Hovenden MJ, Jalava M, Jónsdóttir IS, Juhanson J, Jung JY, Kaarlejärvi E, Kwon MJ, Lamprecht RE, Le Moullec M, Lee H, Marushchak ME, Michelsen A, Munir TM, Myrsky EM, Nielsen CS, Nyberg M, Olofsson J, Óskarsson H, Parker TC, Pedersen EP, Petit Bon M, Petraglia A, Raundrup K, Ravn NMR, Rinnan R, Rodenhizer H, Ryde I, Schmidt NM, Schuur EAG, Sjögersten S, Stark S, Strack M, Tang J, Tolvanen A, Töpper JP, Väisänen MK, van Logtestijn RSP, Voigt C, Walz J, Weedon JT, Yang Y, Ylänne H, Björkman MP, Sarneel JM, and Dorrepaal E
- Subjects
- Arctic Regions, Carbon metabolism, Carbon analysis, Carbon Cycle, Datasets as Topic, Hydrogen-Ion Concentration, Nitrogen metabolism, Nitrogen analysis, Plants metabolism, Seasons, Soil chemistry, Soil Microbiology, Temperature, Time Factors, Ecosystem, Global Warming, Tundra, Cell Respiration
- Abstract
Arctic and alpine tundra ecosystems are large reservoirs of organic carbon
1,2 . Climate warming may stimulate ecosystem respiration and release carbon into the atmosphere3,4 . The magnitude and persistency of this stimulation and the environmental mechanisms that drive its variation remain uncertain5-7 . This hampers the accuracy of global land carbon-climate feedback projections7,8 . Here we synthesize 136 datasets from 56 open-top chamber in situ warming experiments located at 28 arctic and alpine tundra sites which have been running for less than 1 year up to 25 years. We show that a mean rise of 1.4 °C [confidence interval (CI) 0.9-2.0 °C] in air and 0.4 °C [CI 0.2-0.7 °C] in soil temperature results in an increase in growing season ecosystem respiration by 30% [CI 22-38%] (n = 136). Our findings indicate that the stimulation of ecosystem respiration was due to increases in both plant-related and microbial respiration (n = 9) and continued for at least 25 years (n = 136). The magnitude of the warming effects on respiration was driven by variation in warming-induced changes in local soil conditions, that is, changes in total nitrogen concentration and pH and by context-dependent spatial variation in these conditions, in particular total nitrogen concentration and the carbon:nitrogen ratio. Tundra sites with stronger nitrogen limitations and sites in which warming had stimulated plant and microbial nutrient turnover seemed particularly sensitive in their respiration response to warming. The results highlight the importance of local soil conditions and warming-induced changes therein for future climatic impacts on respiration., (© 2024. The Author(s).)- Published
- 2024
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