Restoration and closer-to-nature management in drained peatlands can be a NbS in both private and state-owned forests.  

Why 

During the 19-20th centuries, in Finland, Sweden and Norway, forest peatlands have been drained to serve any of the following four main purposes: 

The negative short- and long-term environmental impacts of drainage include: 

• biodiversity loss
• destroyed original hydrology of a landscape
• reduced peat carbon storage
• soil subsidence and irreversible changes in the soil quality
• reduction in water quality through the discharge of nutrients to ground and surface water
• increased greenhouse gas (GHG) emissions from ditches and decomposing peat
• increased damage risk (flooding, fire, pests and diseases).  

The restoration or adaptive management of forested peatlands is directed to recover the original water table and thus rehabilitate sites for peatland species, and enhance biodiversity. This is especially important for the most threatened fertile and wooded swamps – fens and paludified spruce forests.  

Restoration of forested peatlands is also important for climate change mitigation and adaptation, due to decreased greenhouse gas emissions and restored high capacity of peatlands to store carbon, and water management through slowed discharge of dissolved organic carbon and nutrients. This leads to improved water quality, which is important for human health and wellbeing. Restored peatlands are supposed to have higher resilience not only to climate change, but also to pests and diseases and are less prone to fire. Thus, the NbS addresses societal challenges of disaster risk and preparedness. 

Restoration of the natural hydrology of a site is achieved by filling in or blocking existing ditches. If the site is forested, partial or complete removal of the tree stand or, alternatively, creating deadwood in the form of snags may be included to restore a more or less open mire. To restore a forested mire or a swamp forest, the removal of trees is often not necessary, except for previously planted invasive trees species. The transfer of peat mosses (Sphagnum) may sometimes be needed. To avoid flooding of partly decomposed peatlands it might be necessary to restore hydrology in more than one step, or to aim for a smaller water level rise to make sure to level the current peat surface.  

Potential outcomes

In general, positive effects of peatland restoration include improved ecosystem services, soil health, recreational and aesthetic values. The social outcome is to fulfill the EU’s target to restore degraded ecosystems to halt biodiversity loss. 

ATTENTION 

Costs 

Forest peatland restoration costs include planning and actual performing of the restoration, which usually means either opening the ditches or blocking them. Costs can vary remarkably between the Nordic countries, depending on conditions.