DynaDeep - Aerobe Respiration und Sauerstoffdynamik in oberflächennahen Strandsedimenten
The aim of this project is to investigate the dynamic reactive transport of oxygen as an electron acceptor for microbial processes and the transition to anoxic conditions in the upper sediment layer of a sandy beach infiltration zone. It is part of the DFG research unit “The dynamic deep subsurface of high-energy beaches (DynaDeep)”.
Sand beaches mark a highly dynamic land-ocean interface, influenced by waves, tides, storms and associated morphodynamics. At the beach face, these dynamics control the inflow of water into the porous sand body, carrying electron acceptors for microbial processes such as oxygen but also organic electron donors. However, the interplay between hydrodynamics and biogeochemical processes is poorly understood to date. This project will help to understand how oxic microbial processes in beach sands are controlled by the fluctuating influx of oxygen and organic matter on tidal to seasonal timescales. Therefore, we measure sedimentary oxygen consumption rates and in-situ oxygen concentrations and their responses to changing environmental conditions driven by the beach dynamics and subsurface flow. In the shallow subsurface, we expect organic matter and oxygen supply to be highly variable and to influence the conditions at greater depths in the beach subsurface. The field site for sampling and investigations is the East Frisian Island Spiekeroog.
Website-Link: https://uol.de/icbm/verbundprojekte/dynadeep