Restoring excavated wetlands has been launched as an important climate measure and something that can help Sweden meet the climate goals.
At the same time, it is known that the climate benefits are limited, even though so-called rewetting is often good for nature and biodiversity.
Recovery increases greenhouse gas
Now researchers at SLU in Umeå have seen that restored wetlands can also mean that emissions of greenhouse gases increase.
– One consequence of rewetting is that you can increase the release of methane, which is also a fairly strong greenhouse gas, says Hjalmar Laudon, researcher at SLU.
It is studies at Stormyren near Vindeln that have shown the emissions of methane gas.
Marginal effect in large parts of the country
The research also shows that the reduction of carbon dioxide emissions from restored previously excavated wetlands is marginal in the northern and central parts of the country. Measures in those areas are relatively pointless from a climate perspective, according to SLU.
– Then you should go for very much more nutrient-rich peatlands, then you will have a much greater effect on reducing emissions, says Hjalmar Laudon.
He notes that it is often about agricultural land, especially in southern Sweden. Land that is also needed for food production.
Not the right way
Hjalmar Laudon does not believe that you can count on any reduction in greenhouse gas emissions by restoring wetlands more than marginally.
– As a short-term solution, I don’t think it’s a way to go, then we have to find other solutions, he says.