Preprints
https://doi.org/10.5194/egusphere-2023-3098
https://doi.org/10.5194/egusphere-2023-3098
04 Jan 2024
 | 04 Jan 2024

Seasonal controls on methane flux components in a boreal peatland – combining plant removal and stable isotope analyses

Katharina Jentzsch, Elisa Männistö, Maija E. Marushchak, Aino Korrensalo, Lona van Delden, Eeva-Stiina Tuittila, Christian Knoblauch, and Claire C. Treat

Abstract. Wetlands are the largest natural source of atmospheric methane and highly vulnerable to climate change. In our study we aim to better understand the environmental controls on the strength and seasonal variation of methane flux components from hollows, typically the high-emitting wettest microtopographic features in a boreal bog. We measured methane fluxes from intact vegetation as well as on vegetation removal treatments and analyzed pore water methane concentrations and stable carbon isotopes of dissolved and emitted methane. Using these data, we quantified the rates of total methane emission, methane oxidation and plant-mediated methane transport for the summer and shoulder seasons of 2021 and 2022. Total methane emissions from areas with intact vegetation range from 13 to 2171 mgCH4 m–2 d–1 during shoulder seasons and summer months and are mainly controlled by the leaf area of aerenchymatous plants. Methane oxidation in the Sphagnum moss layer decreases total methane emissions by 82 ± 20 % while transport of methane through aerenchymatous plants increases methane emissions by 80 ± 22 %. Both methane oxidation and plant-mediated methane transport rates follow a seasonal cycle with lower but still significant rates during the shoulder seasons compared to the summer months. As a net effect, the presence of Sphagnum mosses and vascular plants reduces methane emissions from the study site. This balance, however, appears to be highly sensitive to climate change, i.e. increasing soil temperatures and changing leaf area and composition of the wetland vegetation. The provided insights can help to improve the representation of environmental controls on the methane cycle and its seasonal dynamics in process-based models to more accurately predict future methane emissions from boreal peatlands.

Publisher's note: Copernicus Publications remains neutral with regard to jurisdictional claims made in the text, published maps, institutional affiliations, or any other geographical representation in this preprint. The responsibility to include appropriate place names lies with the authors.
Katharina Jentzsch, Elisa Männistö, Maija E. Marushchak, Aino Korrensalo, Lona van Delden, Eeva-Stiina Tuittila, Christian Knoblauch, and Claire C. Treat

Status: final response (author comments only)

Comment types: AC – author | RC – referee | CC – community | EC – editor | CEC – chief editor | : Report abuse
  • RC1: 'Comment on egusphere-2023-3098', Pierre Taillardat, 02 Feb 2024
    • AC2: 'Reply on RC1', Katharina Jentzsch, 07 Mar 2024
  • RC2: 'Comment on egusphere-2023-3098', Anonymous Referee #2, 06 Mar 2024
    • AC1: 'Reply on RC2', Katharina Jentzsch, 07 Mar 2024
Katharina Jentzsch, Elisa Männistö, Maija E. Marushchak, Aino Korrensalo, Lona van Delden, Eeva-Stiina Tuittila, Christian Knoblauch, and Claire C. Treat
Katharina Jentzsch, Elisa Männistö, Maija E. Marushchak, Aino Korrensalo, Lona van Delden, Eeva-Stiina Tuittila, Christian Knoblauch, and Claire C. Treat

Viewed

Total article views: 496 (including HTML, PDF, and XML)
HTML PDF XML Total Supplement BibTeX EndNote
340 132 24 496 37 14 17
  • HTML: 340
  • PDF: 132
  • XML: 24
  • Total: 496
  • Supplement: 37
  • BibTeX: 14
  • EndNote: 17
Views and downloads (calculated since 04 Jan 2024)
Cumulative views and downloads (calculated since 04 Jan 2024)

Viewed (geographical distribution)

Total article views: 488 (including HTML, PDF, and XML) Thereof 488 with geography defined and 0 with unknown origin.
Country # Views %
  • 1
1
 
 
 
 
Latest update: 22 Jun 2024
Download
Short summary
Peatlands store large amounts of carbon which may increasingly be released as greenhouse gases under a warming climate. We research how environmental conditions affect the methane release from a boreal peatland. Vegetation had a strong impact year-round – methane release was reduced by some plant species but increased by others. The total vegetation currently lowers the methane release to the atmosphere. However, this balance can turn around as climate change alters the vegetation composition.