EGU22-10237
https://doi.org/10.5194/egusphere-egu22-10237
EGU General Assembly 2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.

Soil – atmosphere exchange of greenhouse gases under future climates

Nine Douwes Dekker, Josep Barba, Angeliki Kourmouli, Robert Mackenzie, Vincent Gauci, Liz Hamilton, Elise Pendall, Sirwan Yamulki, and Sami Ullah
Nine Douwes Dekker et al.
  • University of Birmingham, Geography, Earth and Environmental Science, United Kingdom of Great Britain – England, Scotland, Wales (nxd934@student.bham.ac.uk)

This research investigates the cascading effects of elevated carbon dioxide (eCO2) fumigation of a mature temperature forest, with a particular focus on the fluxes of greenhouse gases (GHG) nitrous oxide (N2O), methane (CH4) and carbon dioxide (CO2). A field experiment was performed at the Birmingham Institute of Forest Research Free Air Carbon dioxide Enrichment facility (BIFoR FACE), where an oak dominated mixed mature woodland has been under eCO2 since 2017. Fluxes were quantified in situ using the Licor 8100A – an infrared gas analyser measuring total soil respiration (Rs) as CO2, and a Picarro greenhouse gas analyser (G2508), measuringN2O and CH4. Preliminary data from 2019 – 2021 have been analysed and are built on an earlier dataset from 2017-2018, and the role of soil temperature and soil moisture is considered. With more carbon allocation belowground, we expect an increase in microbial activity and consequently larger Rs. Overall, Rs was higher under eCO2 in 2017-2018; however, in years 2019 to 2021, the absolute difference in respiration between eCO2 and control plots gradually decreased and even switched in 2021, with a slight increase in Rs for control plots compared to eCO2 plots. Moreover, annual fluxes of N2O and CH4 were detectable and in general we observed N2O emission and CH4 consumption. My presentation will discuss Rs and N2O and CH4 fluxes and highlight the role of eCO2 as well as environmental and soil conditions that regulate the GHG fluxes, allowing us to compute the net global warming potential of forests under future climates.

How to cite: Douwes Dekker, N., Barba, J., Kourmouli, A., Mackenzie, R., Gauci, V., Hamilton, L., Pendall, E., Yamulki, S., and Ullah, S.: Soil – atmosphere exchange of greenhouse gases under future climates, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-10237, https://doi.org/10.5194/egusphere-egu22-10237, 2022.