About the project
Investigation of the state of the aquatic ecosystem in the Toby River and Södra Stadsfjärden about 7 years after the dredging of the Toby River and Solf River estuaries.Project goal
To monitor water quality, measurements are carried out in the field, and water samples are taken for further analysis. Chlorophyll samples are also taken as an indicator of eutrophication level and amount of food available for zooplankton. Zooplankton are studied because they are an important food for predatory fish fry, such as pike and perch, and because they are sensitive to acidic and metal-rich water. The microbial populations are a key factor in the biogeochemical processes in both the water phase and sediment and directly affect water quality by controlling which substances are dissolved in the water phase and which substances are bound to the sediment.Photo: illustrative image, Adobe Stock.
Impact
We sampled six sites in the project: the upper course of the Laihianjoki/Toby River in Kylänpää, Laihia, which was our reference area with little impact from acid sulfate soils and surrounded by forest and peatland; the lower course of the Toby River at the pumping stations and the Toby River estuary, where the impact of acid sulfate soils is high; the Solf River Estuary, where the impact of acid sulfate soils is high; Södra Stadsfjärden at Svartön and Södra Stadsfjärden at Metgrund, where brackish water dominates. The sampling in spring, summer and autumn was carried out by boat, while the winter sampling was carried out by snowmobile. In Kylänpää, the sampling could be carried out by wading out into the stream, also during the winter sampling, as the flowing water was ice-free.For the immediate monitoring of water quality in the field, a field meter was used. In addition, water samples were taken for analysis in Novia's laboratories. Samples for later analysis at an external laboratory were also taken. A survey of zooplankton diversity in the area was carried out as they are the main food source for fish larvae. A bacterial diversity survey was started as it can be used as an indicator of the health of the aquatic ecosystem and reveal pollution levels.
The results will be published in a scientific journal.
UN's Sustainable Development Goals
Sten Engblom
Research Manager