Dissolved organic matter (DOM) represents the ocean’s largest reservoir of reduced carbon. Despite significant progress, we still lack a mechanistic understanding of the microbial processes contributing to DOM sources and sinks. In this project, we study DOM distributions and optical properties (based on absorbance and fluorescence spectra) together with their interaction with microbial communities in different Red Sea environments including the deep brine pools (in collaboration with Prof. Daniele Daffonchio). In particular, valuable information can be extracted from the fractions absorbing UV and visible light or chromophoric DOM (CDOM) and emitting blue-lightor fluorescent DOM (FDOM). CDOM and FDOM can give us insights on DOM origin, molecular weight, diagenetic state and chemical structure, thus serving as tracers for microbial and geochemical processes.
