Shelf seas, and in particular their permeable sediments, represent globally important bioreactors. In these systems, ‘tidal pumping’ facilitates enhanced advective pore water transport even in deeper permeable sediments where allochthonous dissolved organic matter (DOM) is decomposed, and elements are released back into active cycles.
A focus of my current research will be set on North Sea tidal flats and beaches which serve as natural laboratories where I investigate the turnover of recent (algae and vascular plants) and Holocene (peat) production in permeable sediments. Major tools for this project include molecular fingerprinting with Fourier-transform ion cyclotron resonance mass spectrometry (FT-ICR-MS), molecular and isotopic tracer techniques (e.g. lignin as terrestrial biomarker), and optical fingerprinting (fluorescence and absorbance spectroscopy).