Researchers are investigating how the restoration of a peatland affects its hydrological conditions, greenhouse gases and vegetation

Peatlands depend on moisture, and restoration aims to raise the water levels, and to recover the peatland environments and their diverse, sometimes endangered, species. Raising the water level also prevents the decomposition of old peat and the release of carbon into the atmosphere, while allowing new peat and carbon to build up.

Some of the trees in the area are being cut down, and the trunks and logging residues are used to block the ditches, deviating from the established peatland restoration method of Metsähallitus, where the ditches are filled only with peat. This is done to restore the original tree density and maintain the subsurface water flow typical of aapa mires. Logging residues slow down the water flow, and the released nutrients promote microbial activity, reducing nutrient leaching into downstream waters. Wood biomass in peat increases soil carbon storage.

Restoration is part of the LIFE PeatCarbon project, funded by the European Union from 2022 to 2027 and coordinated by the University of Latvia. Finnish partners in the project include the Finnish Meteorological Institute, the University of Oulu, and the Natural Resources Institute Finland, as well as Metsähallitus, which carries out the restoration measures. Other project partners are from Denmark, Germany, and Latvia.

The mysteries of water cycle are being investigated using various methods and combined with modeling

A research group from the University of Oulu is investigating how restoration changes hydrological conditions in the area.

"When ditches are blocked, where does, for example, spring meltwater flow? Surface water flows are expected to become more even, and as the groundwater level rises, greenhouse gas emissions decrease. We are building models of these effects on the catchment water system, which will allow us to assess the effects of restoration up to 50 years into the future," says doctoral researcher Anna Autio from the University of Oulu.

To refine their models, researchers from the University of Oulu conduct wireless monitoring. Ground penetrating radar surveys are also conducted in the spring. Measurements determine the thickness of peat layer and soil structures, such as rapidly permeable sand layers, to determine where water goes or stays. Modeling is being developed so that the effects of restoration in other areas can also be assessed using these models.

The University of Oulu's research in the Pallas region is part of projects funded by the Academy of Finland and the EU, as well as the flagship project Digital Waters.

Matorovansuo and Välisuo peatlands are one of the northernmost restoration sites in the world, where the effects on hydrology, greenhouse gases, vegetation, and microbiota will be closely monitored in the coming years.

Changes in greenhouse gases and vegetation are being investigated through joint research

The Finnish Meteorological Institute and the Natural Resources Institute Finland measure greenhouse gas fluxes (carbon dioxide, methane, and nitrous oxide) in the restored areas before and after restoration. This allows for the quantification of the impact of restoration on peatlands immediately in the first years after the intervention. Continuous micrometeorological eddy covariance measurement is one of the state-of-the-art measurement methods used.

"It is expected that restoration will quickly lead to changes in water conditions and greenhouse gas balances, but changes in vegetation will take longer to become apparent. The Natural Resources Institute Finland is studying the effects of restoration on the area's vegetation and microbial communities by measuring them before and after restoration. Remote sensing methods play an important role," says Senior Researcher Jenni Hultman from the Natural Resources Institute Finland.

Microbes are studied using precise sequencing methods that provide information not only about species but also about microbial functionality. Functions related to greenhouse gas cycles are of particular interest.

Measurements are used to support modelling of greenhouse gas budgets. Researchers from the Finnish Meteorological Institute are modelling the effects of restoration on the area's greenhouse gas balances and peat carbon storage decades into the future.

"Simulations seek to answer questions such as how climate change affects greenhouse gas balances and soil water conditions, and how fast peat accumulates. These questions will be answered by models that accurately describe peat and vegetation processes," says Principal Scientist Tuula Aalto from the Finnish Meteorological Institute.

The research is part of the Finnish Meteorological Institute's long-term research activities in the Pallas region.

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