Experimental approach to study the climate effects from drained peatland restauration
- 1Dept. of Environmental Engineering,Technical University of Denmark, Lyngby, Denmark (anib@env.dtu.dk)
- 2Dept. of Geosciences, University of Oslo, Oslo, Norway (norbert.pirk@geo.uio.no)
- 3Dept. Geosciences and Natural Resource Management University of Copenhagen, Copemhagen, Denmark (ksl@ign.ku.dk)
- 4DMR Miljø og Geoteknikk AS, Oslo, Norway (pla@dmr.dk)
Peatlands have been traditionally drained to increase productivity. Aeration of the topsoil increases decomposition of peat, which results in increased CO2 emissions contributing to warming of the global climate. Peatland restauration tries to reestablish the natural state by blocking the drainage and increasing the ground water table. Two questions arise, whether the establishment of anaerobic conditions in the peat will increase methane production and whether the net CO2 uptake by plants will be reduced, both of which offsetting the anticipated positive climate effect from peatland restauration. In order to claim a positive climate effect from peatland restauration, the effect on the total greenhouse gas (GHG) balance must be demonstrated[VH1] at different time scales.
In a new project in Norway (close to Trysil, Innlandet), we established a paired plot design in an ombrotrophic bog, where one of the two plots will be restored, while the other will remain drained. The two sites differ slightly in elevation and lie 1.5 km apart from each other. We report results from the first phase of the experiment, i.e. examining the comparability of the two plots. We use eddy covariance and ecosystem chambers to measure CO2, CH4 and N2O fluxes.
While the CO2 fluxes are remarkably similar between the two plots, the CH4 fluxes tend to be slightly higher in the lower of the two plots. With flux footprint simulations and spatio-temporal analysis of the chamber flux measurements it is examined, whether these differences are caused by small scale horizontal heterogeneity, i.e. by CH4 emission hotspots, or whether these are a general feature of the lower experimental site. Options to improve the comparability of the two experimental plots, namely source area filtering versus relational approaches will be discussed.
The methodology that is developed in the project is relevant for monitoring, reporting and verification of climate change mitigation measures within terrestrial ecosystems.
Acknowledgements:
The project is funded by the Norwegian Environment Agency (Miljødirektoratet), Oslo, Norway, (project number 18088061).
How to cite: Ibrom, A., Pirk, N., Steenberg Larsen, K., Kindler, P. A., and Larsen, P.: Experimental approach to study the climate effects from drained peatland restauration, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-6602, https://doi.org/10.5194/egusphere-egu2020-6602, 2020
