Wetlands – the silent heroes of nature
Wetlands are one of the most underappreciated, yet complex and important ecosystems on Earth. They are not just “wet fields” or “swamps and bogs,” as is sometimes thought. Wetlands are silent heroes—they do a tremendous amount of work for us without us even noticing. They purify water, balance the climate, provide a home for thousands of species, and protect us from flooding. And best of all... wetlands also help to protect freshwater pearl mussels, one of the most sensitive and demanding species in our rivers. Freshwater pearl mussels need clean, cool, oxygenated flowing water without too much sediment or nutrient loading. This makes it an excellent indicator species: if the freshwater pearl mussel is doing well, then the river system is also in good condition.
What exactly is a wetland?
Simply put, a wetland is an area where the land is either permanently or periodically covered by water. It can be natural or constructed, permanent or temporary. Wetlands are considered one of the most endangered habitats in the world. Wetlands include, for example: mires, bogs, fens, floodplains, riverine meadows, coastal wetlands and mudflats and artificial wetlands constructed for water protection purposes.
There are many wetlands in Finland, but their number has decreased significantly due to drainage, intensification of agriculture, and construction. In this blogtext, I will discuss why wetlands are vital, what benefits they offer, and why they are being created in the LIFE Revives project.
Why are wetlands so important?
Wetlands provide many ecosystem services that benefit people and nature.
1. Biodiversity
Wetlands are teeming with life. They provide a habitat for many plants and animals, including waterfowl, amphibians, and insects. They also serve as resting places for migratory birds and support species diversity. Wetlands are not directly the habitat of the freshwater pearl mussel, but they protect the catchment area upstream of rivers. When the catchment area is healthy, the living conditions of the freshwater pearl mussel are also better in the rivers.
2. Flood protection
Wetlands act like sponges. They store large amounts of water and release it slowly. This reduces the risk of flooding and mitigates the effects of extreme weather events, such as flooding caused by heavy rainfall. Looking ahead, droughts and heavy rainfall are set to increase because of climate change. Wetlands even water flow and prevent sudden changes that are harmful to mussels.
3. Nature's own water treatment plant
Wetlands function by regulating flow velocity. Water flow slows down in wetlands, allowing solids and nutrients carried by the water to settle at the bottom of the wetland. A functioning wetland can retain up to 90 percent of the solids and nutrients carried by the water. One of the greatest threats to freshwater mussels is fine-grained sediment (sand, clay, humus), which clogs the riverbed and prevents young mussels from surviving.
4. Carbon sequestration and climate regulation
Wetlands are effective carbon sinks that bind carbon dioxide from the atmosphere and store it in the soil and vegetation. They also slow down the decomposition of organic matter, which means that the carbon bound in plants remains stored for longer and does not quickly return to the atmosphere.
5. Landscape value and recreation
Wetlands increase landscape diversity and provide places for bird watching, nature hiking, and experiencing silence.
Three wetlands in the catchment areas of Pirkanmaa's FPM rivers
The LIFE Revives project is carrying out restoration work on the river and its catchment area. Three wetlands have been built in the catchment areas of Pirkanmaa's FPM rivers. There are three FPM rivers in Pirkanmaa: The Pinsiön-Matalusjoki on the border between Nokia and Hämeenkyrö, the Ruonanjoki on the border between Ylöjärvi and Hämeenkyrö, and the Turkimusoja in Hämeenkyrö. The wetlands were built in the catchment areas of the Ruonanjoki and Pinsiön-Matalusjoki rivers.
Landowners play a particularly important role
Before work began on the wetland, wetland plans were drawn up, and discussions were held with landowners. The total area of the wetlands varies between 1.6 and 2.17 hectares. The wetlands were designed by Timo Niemelä of KVVY Tutkimus Oy. The work was carried out by civil engineering contractors Jari Perälä and Wiljam Murto. Before construction work began, trees were removed from the areas as necessary. The practical excavation and construction work on the wetlands continued immediately after the logging work was completed as winter work, so that the impact on waterways during the work was kept to a minimum. The excavation work began with the construction of islets and headlands, followed by the construction of embankments. Below are pictures of the LIFE Revives -project’s wetlands construction sites.
Three completed wetlands in the catchment area
The wetlands were completed in a perfect manner. Below are pictures of the completed wetlands that were built in the LIFE Revives project.