Quantifying the ecological and evolutionary cost of chemical mixtures

Research Project, 2020 – 2021

The aim of this project is to determine whether environmentally realistic chemical mixtures function as evolutionary drivers that cause changes in biodiversity and susequent loss of resilience and structural and functional deterioration of pelagic plankton communities. We will use marine plankton communities as our model system as these can be kept under near-realistic conditions while providing a high diversity of test organisms. Three model mixtures will be tested, one that represents contamination from shipping activities, one that represents sewage treatment plants and one that is a mixture of both in order to simulate different coastal habitats. The plankton communities are exposed for three copepod generations which implies many more generations for the phytoplankton. Changes in community diversity will be analysed using image analysis (Zoo/Phyto image) and genotyping-by-sequencing will be used for population genetic changes. Community productivity as changes in biomass is followed over the whole experimental period and the 2nd generation of copepods will be subjected to a salinity stress test to measure changes in resilience. The project will contribute will knowledge on the evolutionary and ecological potential of chemical mixtures at realistic concentrations to shape marine plankton communities. The results, methods and end-points will contribute to the development of a more holistic approach to ecological risk assessment of mixtures that is lacking today.