Effects of nutrient stoichiometry on marine bacteria and organic matter cycling

Ocean warming, changing nutrient supply ratios and other global drivers threaten marine ecosystems.

Marine bacteria are the main contributors to organic carbon turnover in the microbial loop and via their respiration directly influence how much carbon is stored or excluded from long-term storage in the ocean.

Yet, they are rarely included in ocean change research and there is no consensus about climate change impacts on marine microbes. We cannot afford to ignore learning how microbes combat and contribute to climate change.

This project aims to understand and quantify how marine microbial diversity and functioning affects organic carbon turnover under varying nutrient supply regimes in coastal areas.

Given the complex species interactions in natural communities, state-of-the-art molecular data and novel system biology approaches are needed to detect species-specific reactions to environmental drivers.

We will use laboratory model communities and field experiments, per-cell respiration rates, and exometabolomics to identify individual bacterial contribution to organic carbon turnover under different nutrient stoichiometry and trace metal concentrations.

The project will raise awareness and disseminate knowledge on the microbial´s role in ocean processes and contribute to challenge 2 and 4 of the ocean decade and Agenda 2030 goals 13 and 14.