Warming impacts on boreal fen CO2 exchange under wet and dry conditions

© 2019 John Wiley & Sons Ltd.

Bibliographische Detailangaben
Veröffentlicht in:Global change biology. - 1999. - 25(2019), 6 vom: 15. Juni, Seite 1995-2008
1. Verfasser: Laine, Anna M (VerfasserIn)
Weitere Verfasser: Mäkiranta, Päivi, Laiho, Raija, Mehtätalo, Lauri, Penttilä, Timo, Korrensalo, Aino, Minkkinen, Kari, Fritze, Hannu, Tuittila, Eeva-Stiina
Format: Online-Aufsatz
Sprache:English
Veröffentlicht: 2019
Zugriff auf das übergeordnete Werk:Global change biology
Schlagworte:Journal Article Research Support, Non-U.S. Gov't OTC carbon dioxide ecosystem respiration gross photosynthesis peatland warming water level drawdown Soil mehr... Carbon Dioxide 142M471B3J
Beschreibung
Zusammenfassung:© 2019 John Wiley & Sons Ltd.
Northern peatlands form a major soil carbon (C) stock. With climate change, peatland C mineralization is expected to increase, which in turn would accelerate climate change. A particularity of peatlands is the importance of soil aeration, which regulates peatland functioning and likely modulates the responses to warming climate. Our aim is to assess the impacts of warming on a southern boreal and a sub-arctic sedge fen carbon dioxide (CO2 ) exchange under two plausible water table regimes: wet and moderately dry. We focused this study on minerotrophic treeless sedge fens, as they are common peatland types at boreal and (sub)arctic areas, which are expected to face the highest rates of climate warming. In addition, fens are expected to respond to environmental changes faster than the nutrient poor bogs. Our study confirmed that CO2 exchange is more strongly affected by drying than warming. Experimental water level draw-down (WLD) significantly increased gross photosynthesis and ecosystem respiration. Warming alone had insignificant impacts on the CO2 exchange components, but when combined with WLD it further increased ecosystem respiration. In the southern fen, CO2 uptake decreased due to WLD, which was amplified by warming, while at northern fen it remained stable. As a conclusion, our results suggest that a very small difference in the WLD may be decisive, whether the C sink of a fen decreases, or whether the system is able to adapt within its regime and maintain its functions. Moreover, the water table has a role in determining how much the increased temperature impacts the CO2 exchange
Beschreibung:Date Completed 10.07.2019
Date Revised 10.07.2019
published: Print-Electronic
Citation Status MEDLINE
ISSN:1365-2486
DOI:10.1111/gcb.14617