AGU Advances (Sep 2020)

Rapid Net Carbon Loss From a Whole‐Ecosystem Warmed Peatland

  • Paul J. Hanson,
  • Natalie A. Griffiths,
  • Colleen M. Iversen,
  • Richard J. Norby,
  • Stephen D. Sebestyen,
  • Jana R. Phillips,
  • Jeffrey P. Chanton,
  • Randall K. Kolka,
  • Avni Malhotra,
  • Keith C. Oleheiser,
  • Jeffrey M. Warren,
  • Xiaoying Shi,
  • Xiaojuan Yang,
  • Jiafu Mao,
  • Daniel M. Ricciuto

DOI
https://doi.org/10.1029/2020AV000163
Journal volume & issue
Vol. 1, no. 3
pp. n/a – n/a

Abstract

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Abstract To evaluate boreal peatland C losses from warming, novel technologies were used to expose intact bog plots in northern Minnesota to a range of future temperatures (+0°C to +9°C) with and without elevated CO2 (eCO2). After 3 years, warming linearly increased net C loss at a rate of 31.3 g C·m−2·year−1·°C−1. Increasing losses were associated with increased decomposition and corroborated by measures of declining peat elevation. Effects of eCO2 were minor. Results indicate a range of C losses from boreal peatlands 4.5 to 18 times faster than historical rates of accumulation, with substantial emissions of CO2 and CH4 to the atmosphere. A model of peatland C cycle captured the temperature response dominated by peat decomposition under ambient CO2, but improvements will be needed to predict the lack of observable responses to elevated CO2 concentrations thus far.

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