Project Details
Projekt
Morphodynamics, subsurface flow and transport
Applicants
Professorin Dr. Gudrun Massmann; Professor Dr. Mike Müller-Petke; Professor Dr. Christian Winter
Subject Area
Hydrogeology, Hydrology, Limnology, Urban Water Management, Water Chemistry, Integrated Water Resources Management
Geophysics
Oceanography
Geophysics
Oceanography
Term
since 2021
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 431491505
DynaDeep unravels the functionality and relevance of marine-terrestrial interactions below high-energy beaches, where the deep subsurface acts as a dynamic bioreactor and unique microbial habitat affecting elemental net fluxes to the sea. In Phase 1, the DynaDeep team installed an unparalleled observatory on Spiekeroog, where we collected a novel data set in interdisciplinary field campaigns that were supported by laboratory work and modelling. Our results highlight the transient nature of high-energy beaches, where changing environmental conditions are observed tenths of meters deep in the subsurface, mainly caused by morphological changes and stormfloods. Subproject P1 studies how tides, waves and beach morphodynamics affect transient groundwater flow and transport on different spatio-temporal scales. At our core field-site at Spiekeroog, we specifically address the role of the foreshore wave transformation on morphodynamics and associated groundwater flow and transport as well as the effect of major stormfloods on infiltration rates and subsurface salinities in Phase 2. We will assess the transferability of our Spiekeroog findings regarding the relationship between frequency and amplitude of morphological changes and groundwater salinity, age and temperature patterns at two validation sites (De Panne and Truc Vert). Our methods include beach and foreshore morphology surveys using camera imaging, laser-scanning and drones in combination with numerical models to derive typical adaptation time- and length scales of the beach morphology. Geophysical methods will continue to identify subsurface salinity patterns and their change over time. We will further use environmental tracer data to estimate subsurface residence times. Morphological, hydro(geo)logical and geophysical data from all field sites inform numerical groundwater flow and transport modelling to provide a comprehensive and generalizable picture of the subsurface of high-energy beaches. This knowledge on the distribution of water bodies, flow velocities, residence times and extent of mixing from all three sites will provide the basis for biogeochemical investigations carried out in subprojects P2-P6 and inform global modelling in P7.
DFG Programme
Research Units
