Bimodal diel pattern in peatland ecosystem respiration rebuts uniform temperature response

Abstract

Accurate projections of climate change impacts on the vast carbon stores of northern peatlands require detailed knowledge of ecosystem respiration (ER) and its heterotrophic (Rh) and autotrophic (Ra) components. Currently, however, standard flux measurement techniques, i.e. eddy covariance and manual chambers, generate empirical ER data during only night- or daytime, respectively, which are extrapolated to the daily scale based on the paradigm that assumes a uniform diel temperature response. Here, using continuous autochamber measurements, we demonstrate a distinct bimodal pattern in diel peatland ER which contrasts the unimodal pattern inherent to the classical assumption. This feature results from divergent temperature dependencies of day- and nighttime ER due to varying contributions from Rh and Ra. We further find that disregarding these bimodal dynamics causes significant bias in ER estimates across multiple temporal scales. This calls for improved process-based understanding of ER to advance our ability to simulate peatland carbon cycle-climate feedbacks.

Published in

Nature Communications
2020, volume: 11, number: 1, article number: 4255
Publisher: NATURE PUBLISHING GROUP

SLU Authors

• Järveoja, Järvi

  • Department of Forest Ecology and Management, Swedish University of Agricultural Sciences
    

• Nilsson, Mats

  • Department of Forest Ecology and Management, Swedish University of Agricultural Sciences
    

• Peichl, Matthias

  • Department of Forest Ecology and Management, Swedish University of Agricultural Sciences
    

Global goals (SDG)

SDG13 Climate action

UKÄ Subject classification

Ecology

Publication identifier

• DOI: https://doi.org/10.1038/s41467-020-18027-1

Permanent link to this page (URI)

https://res.slu.se/id/publ/107884