Marine ecosystems are vulnerable to ongoing climatic change and are increasingly experiencing multiple disturbances along with the expanding human population. Chemical stressors in the form of dissolved nutrients and pollutants are one of the biggest consequences of recent human activities in the marine environment. There is still a lack of quantitative data and understanding on how these chemical stressors interact in marine ecosystems and combine with climate change.
This doctoral research aims to acquire a better understanding of the relative contribution of changing environmental conditions and chemical stressors to changes at the base of the pelagic food web in the Belgian Part of the North Sea. Firstly, the main drivers of change for the zooplankton community will be determined by means of ecological modelling. The zooplankton forms the base of the marine pelagic food web, making it a good indicator of stressor effects on the overall functioning of the ecosystem under study. The hypotheses put forward by the constructed models will be validated by means of lab experiments for selected copepod species. Finally, feeding and toxicological experiments will be combined to determine indirect (through copepod food) and direct effects of the main stressors on fish larvae in order to investigate which implications the accumulated effects have on higher trophic levels.
