Abstract
Our coastal waters are subject to a number of environmental stressors, such as eutrophication, temperature increase and deoxygenation. Recently, another stressor has received considerable scientific and societal attention - ocean acidification. Ocean acidification is caused by the increase in carbon dioxide pressure as a consequence of increased carbon emissions to the atmosphere, foremost due to burning of fossil fuels. For coastal seas, the situation is more complex with several other factors such as increased amount of organic matter and larger runoff from land also contribute to lowering the pH. We want to study the impact of different pH-lowering drivers and reconstruct how the benthic environment in the Skagerrak - Baltic region has changed over the past 200 years. We plan to sample water and sediment cores, sediments containing calcareous microorganisms -foraminifera. Foraminifera are key calcite producers and excellent tools for understanding past marine environments. The water- and sediment samples will be analysed for various geochemical variables as well as fauna and shells analyses on foraminifera will be conducted. Pilot studies, based on micro-computed tomography, display already a considerable increase in foraminiferal shell dissolution. It is very important that we learn more about the impacts on marine ecosystems of marine acidification in conjunction with other environmental stressors in order to put adequate measures in place.
Sweden