N0.10 Subterranean estuaries’ influence on SGD (Subtest-SGD)

The subgroup focuses on subterranean estuaries (STEs) as key interfaces between terrestrial groundwater and coastal oceans. It investigates how mixing between fresh groundwater and recirculated seawater in permeable coastal aquifers drives biogeochemical transformations that regulate submarine groundwater discharge (SGD). Central to its work is a process-based understanding of hydrological exchange, reactive transport, and microbiological dynamics controlling fluxes of nutrients, carbon, trace elements, and gases.

Specific research themes include:
(i) physical behaviour of groundwater–seawater exchange in coastal aquifers, the physicochemical structure, and the spatio-temporal extent of STEs;
(ii) transport and reaction processes controlling nutrients, carbon, redox-sensitive elements, and gases in STEs and implications for chemical fluxes in SGD;
(iii) methodological harmonization between field observations and models; and
(iv) evaluation of STEs as ecosystems with high socioeconomic relevance experiencing significant man-made pressures (e.g. coastal squeeze through land reclamation, coastal construction, recreational use, sea level rise etc).