Project: Metal accumulation in the Baltic Sea sediments: implications for environmental monitoring programs and mitigation actions
The load of trace metals to Baltic Sea waters and their accumulation in the sediments is a major environmental problem, which is possibly connected to the geochemistry of water and sediments. We propose to study in this project the distribution of trace metals in pore waters and as solid phases in sediments of the Baltic Sea.
Project manager Marcelo Ketzer Other project members Mats Åström, Sina Shahabi Participating organizations Linnaeus University Financier The Swedish geological survey (Sveriges geologiska undersökning; SGU) Timetable 1 Jan 2019–31 Dec 2021 Subject Environmental science (Department of biology and environmental science, Faculty of health and life sciences)
More about the project
The load of trace metals to Baltic Sea waters and their accumulation in the sediments is a major environmental problem, which is possibly connected to the geochemistry (e.g., redox conditions) of water and sediments.
We propose to study in this project the distribution (concentration and speciation) of trace metals (such as As, Hg, and Cd) in pore waters and as solid phases in sediments of the Baltic Sea, using sediment cores that will be obtained during the monitoring campaign to be performed by the Swedish geological survey (Sveriges geologiska undersökning; SGU) to the Swedish Environmental Protection Agency (Naturvårdsverket) in 2020. We will study trace metals distribution in space (shallow and deep waters) and time (from pre-industrial times to present-day), and will also conduct laboratory experiments to investigate how changes in geochemical (e.g., redox) conditions in the water will affect metal availability in the Baltic Sea in the future.
Changes in geochemical conditions, which can be related to climate change, eutrophication, invasion of oxygen-rich North Sea waters, and/or proposed engineering mitigation options to re-establish oxic condition of bottom waters, will play a key role in determining whether certain trace metals may be precipitated and immobilised in a solid phase (e.g. in the structure of a mineral or adsorbed in a solid surface) or in a more mobile phase (dissolved in waters). Changes in geochemical condition may, however, mobilise trace metals that are in more stable phases if geochemical conditions are altered owing to, for instance, oxidation of sulphide minerals.
We strongly believe that our project will add value to current monitoring efforts in the Baltic Sea and will improve our understanding of the geochemical behaviour of trace metals in sediments and water. The latter will be of great help to predict spreading of contaminants (trace metals), risks of contamination to animals (and humans), and the future environmental conditions of the Baltic Sea in general.