Restoring Wetlands

Turning a forest back into a biodiverse, carbon rich wetland

Over recent decades, large swathes of Slovakia’s wetlands have been lost. They have been drained to make way for agriculture as a result of the construction of dams for hydroelectric power, as well as for timber production. Wetlands are an integral part of the Danube floodplain landscape in Slovakia and draining them to plant trees has detrimental impacts on the environment. Wetlands store large amounts of carbon and are home to a diversity of plant and animal species that are specially adapted to the wet conditions. One of these species is the nationally endangered and endemic Pannonian root vole, which has declined drastically in Slovakia in response to disappearing wetlands. This project will turn forest back into a wetland by digging 650 meters of ditches. This will kickstart a “flood” of change and bring back a healthy functioning, sustainable and wilder ecosystem.

The Intervention

This ambitious project aims to restore an area of degraded wetland by digging water channels that will reconnect the site to a nearby river. These channels will enable water to travel from the river to the core area of the wetland and restore a more beneficial flooding regime. The project will also remove encroaching woody vegetation that is outcompeting the native wetland plant communities.

Over time this intervention will:

  • create suitable conditions for the regeneration of the wetland plant communities;
  • suppress the expansion of non-native plant species;
  • create suitable habitat for a diversity of invertebrates, amphibians, birds and mammals;
  • and finally, sequester vast amounts of carbon.

Within the next two years, we will be supporting our partners Broz to create 650 meters of water channels to restore a 64ha wetland.

The site of the wetland restoration project by Mossy Earth and Broz.
The degraded wetland area we are working to restore on the Danube floodplain in Slovakia.

Learn More About the Context Behind this Project

The Importance of Wetlands

Wetlands can be found anywhere water interacts with land. The diverse and complex conditions of wetland habitats can support a diversity species, including an abundance of invertebrate and bird life. Wetlands are therefore some of the most biodiverse ecosystems on earth. They also play a crucial role when it comes to climate change. They help fight floods by absorbing excess water and limit droughts by releasing water slowly.

A grey heron, an ibis and a gull stand in a pond filled with lily pads.
Wetlands are centres for biodiversity, hosting an abundance of plant, invertebrate and bird species.

Wetlands and Carbon

The waterlogged conditions combined with high plant productivity make many freshwater wetlands, including the wetlands we are restoring, significant carbon sinks. Our wetland has the potential to sequester between 200 – 350 tonnes of carbon per year (Mitsch et al., 2013; Brix et al. 2001). When converted to carbon dioxide this means that every year it will sequester about 1290 tonnes of CO2 out of the atmosphere. That is the equivalent of you taking 3902 flights between Lisbon and London or the full footprint of about 189 average Europeans each year.

River Danube in Slovakia, the location of Mossy Earth's wetland restoration project.
The waterlogged conditions make wetlands are great carbon sink

Saving a Glacial Relict

The Pannonian root vole is what’s known as a glacial relict. This means it is a species leftover from the cold-adapted communities of the Ice Age. As the climate warmed and the continental ice sheets retreated, the Pannonian root vole population disappeared from most of its range. However, it managed to avoid complete extinction, surviving as isolated populations in the vicinity of the Danube river in Slovakia, Hungary and Austria.

Despite clinging on for thousands of years after the Ice Age, the Pannonian root vole is now under immense pressure from human activity. As well as having an already restricted range, the Pannonian root vole has very specific habitat requirements, which makes it a particularly sensitive species.

Their survival hinges upon the conservation and restoration of functioning wetland habitats.

A Pannonian root vole, the target species to protect in Mossy Earth's wetland restoration project.
The pannonian root vole is one of many species that will benefit from the restoration of wetlands in Sovakia.

Our Project Area

The site we are restoring was drained during the 80s and 90s primarily due to the construction of a dam, and secondarily to create suitable conditions for timber production. An extensive wetland ecosystem, 80ha in size, was lost. This is a perfect example of how not all tree planting is beneficial to the environment.

Today, the site still floods, but very rarely and for such a short period of time that the wetland’s natural communities are unable to establish. The native plant species that are important for the Pannonian root vole are still declining and being replaced by woody vegetation, such as shrubs and trees, and invasive plants are taking over. Our intervention aims to reverse this trend.

Tall brown reeds stand upright in the foreground against a background of trees
Restoring the wetlands will encourage native wetland plants to prosper over more woody vegetation.
Heart Image

the team behind the project

Team Member

Jakub Sigmund, Field Manager at Broz

Team Member

Žofia Filagová, Project Manager at Broz (right)

Team Member

Hannah Kirkland, Conservation Biologist at Mossy Earth

Sources & further reading

Peer Reviewed Research Section
  1. Wetlands, carbon, and climate change - Mitsch et al.External linkIcon Peer Review
  2. Are Phragmites-dominated wetlands a net source or net sink of greenhouse gases? - Brix et al.External linkIcon Peer Review