Carbon loss from northern circumpolar permafrost soils amplified by rhizosphere priming

verfasst von

Frida Keuper, Birgit Wild, Matti Kummu, Christian Beer, Gesche Blume-Werry, Sébastien Fontaine, Konstantin Gavazov, Norman Gentsch, Georg Guggenberger, Gustaf Hugelius, Mika Jalava, Charles Koven, Eveline J. Krab, Peter Kuhry, Sylvain Monteux, Andreas Richter, Tanvir Shahzad, James T. Weedon, Ellen Dorrepaal

Abstract

As global temperatures continue to rise, a key uncertainty of climate projections is the microbial decomposition of vast organic carbon stocks in thawing permafrost soils. Decomposition rates can accelerate up to fourfold in the presence of plant roots, and this mechanism—termed the rhizosphere priming effect—may be especially relevant to thawing permafrost soils as rising temperatures also stimulate plant productivity in the Arctic. However, priming is currently not explicitly included in any model projections of future carbon losses from the permafrost area. Here, we combine high-resolution spatial and depth-resolved datasets of key plant and permafrost properties with empirical relationships of priming effects from living plants on microbial respiration. We show that rhizosphere priming amplifies overall soil respiration in permafrost-affected ecosystems by ~12%, which translates to a priming-induced absolute loss of ~40 Pg soil carbon from the northern permafrost area by 2100. Our findings highlight the need to include fine-scale ecological interactions in order to accurately predict large-scale greenhouse gas emissions, and suggest even tighter restrictions on the estimated 200 Pg anthropogenic carbon emission budget to keep global warming below 1.5 °C.

Organisationseinheit(en)

Institut für Bodenkunde

Externe Organisation(en)

Universität Umeå
Stockholm University
Göteborgs Universitet
Aalto University
Universität Hamburg
Universität Greifswald
Swiss Federal Institute for Forest, Snow and Landscape Research (WSL)
Lawrence Berkeley National Laboratory
Swedish University of Agricultural Sciences
Universität Wien
International Institute for Applied Systems Analysis, Laxenburg
Government College University Faisalabad
Vrije Universiteit Amsterdam
Institut national de recherche pour l’agriculture, l’alimentation et l’environnement (INRAE)
Russian Academy of Sciences (RAS)

Typ

Artikel

Journal

Nature geoscience

Band

13

Seiten

560-565

Anzahl der Seiten

6

ISSN

1752-0894

Publikationsdatum

08.2020

Publikationsstatus

Veröffentlicht

Peer-reviewed

Ja

ASJC Scopus Sachgebiete

Allgemeine Erdkunde und Planetologie

Ziele für nachhaltige Entwicklung

SDG 13 – Klimaschutzmaßnahmen

Elektronische Version(en)

https://aaltodoc.aalto.fi/handle/123456789/45714 (Zugang: Offen)
https://doi.org/10.1038/s41561-020-0607-0 (Zugang: Geschlossen)