Guiding drained peatland management towards negative GHG emissions

In a world of climate change we need to minimize and stop greenhouse gas (GHG) emissions and instead accumulate carbon in ecosystems - we call this ‘negative emissions’. Drained peatlands are in many cases large sources of GHGs to the atmosphere but rewetting of a peatland can mitigate these emissions and possibly reach a net uptake. However, carbon accumulation in peatlands is a dynamic and complex balance between uptake and release, which is mainly driven by the groundwater table (WT) depth.

                           Our new project funded by the Swedish Research Council FORMAS (2020-2022) aims to produce a handbook with guidance on how to change management of drained organic soil in order to convert them into low or negative emission peatlands. Researchers from Gothenburg, Stockholm, Lund and York Universities will collaborate with landowners, public authorities and NGO’s to assemble the most relevant knowledge.

We will compare GHG fluxes from organic soils under different traditional and newly suggested land uses in the Swedish landscape, by collected field data, which will be the input for upscaling in time and space by using state-of-the-art process models (CoupModel and ForSAFE). For modelling purposes, extensive abiotic and GHG datasets will be available from the research station ‘Skogaryd’ in Västra Götaland, Sweden (https://gvc.gu.se/english/research/skogaryd), from a drained peat with spruce forest, before and after the clear-cut in 2019. This clear-cut area will now be partly rewetted by building a dam, and GHG flux measurements will be collected in response to different soil WT and vegetation types. Other available data are from a variety of drained and rewetted peat soils in neighboring countries. In addition, GHG measurements in Sweden on restored bogs are starting during summer 2020. Models will allow us to assess and examine the influence of 1) WT fluctuations, 2) soil fertility, and 3) management on both carbon storage and GHG fluxes for rewetted cases with moss vegetation, meadow or swamp forest.