The research in Baltic TRANSCOAST is organized in 13 PhD topics in three research fields with hydro-dynamic (H), (bio)geochemical (G), and biological (B) focus.

H1: Marine and terrestrial influence on submarine groundwater discharge in coastal waters connected to a peatland. The general aim of this topic is to quantify water and solute inputs from a shallow coast to the Baltic Sea. We will quantify the exchange between groundwater and sea water, taking into account the spatial distribution and temporal dynamics of submarine groundwater discharge (SGD)... more

H2: Flow and solute transport anomalies in coastal fen peats. We are aiming at characterizing the flow and transport properties of (degraded) peat soils and –at a later stage- to link physical non-equilibrium phenomena to geochemical transformation processes. The work programme includes laboratory and field tests... more

H3: Downscaling (process oriented localization) of larger scale simulations of sea water currents to assess interactions between sea and groundwater bodies. The aim of this topic is to quantitatively investigate the exchange of water, solutes and particulate matter mediated by submarine groundwater discharge (SGD) and its impact on the coastal ocean. It will be the challenge to combine physical forcing with biogeochemical transformations... more

H4: Waves and turbulence on wavy coastal seabeds inducing vertical scalar transport. The mixing process on and above the structured permeable seabed is investigated in a defined laboratory experiment to foster our understanding of turbulence and mixing in shallow coastal waters... more

G1: The influence of terrestrial input on fluxes from and element (C-N-S-P, metals) transformations in shallow water sands of the Baltic Sea coast. The influence of water (submarine groundwater discharge, SGD) and substances from the peatland to the Baltic Sea for element transformations in and fluxes from sandy sediments is in the target of this topic... more

G2: Climate relevant trace gases in shallow waters impacted by terrestrial nutrient input from a coastal peatland. Quantification of trace gases in coastal waters in relation to other environmental parameters like temperature and substrate concentration... more

G3: Plant and microbial drivers of methane exchange and their relationship in a coastal peatland. Within this topic, we will address the influence of spatial and temporal variability in salinity and sulphate concentration (i) on the composition and productivity of the microbial community as well as (ii) on the primary production, substrate supply and CH₄ transport through the vegetation... more

G4: Influence of salinity dynamics on the release, chemical structure and biological transformations of dissolved organic matter in a coastal peatland. We want to develop a general understanding, how the salinity dynamics in a coastal peatland (NSG „Heiligensee und Hütelmoor“ as a well characterized and intensively studied, joint “playground” of the Research Training Group) affect the DOM-release, –composition and –dynamics (objective 1)... more

B1: Impact of nutrient emissions from land on the species composition and productivity of communities of macrophytes in shallow waters. Macrophytobenthos composition, seasonality and productivity of ground-water influenced plots will be compared with neighboring uninfluenced areas. The main focus ist to unravel the impact of sub-surface freshwater inflow on species composition and productivity in the „critical salinity range“... more

B2: Microphytobenthic primary production in biofilms along terrestrial-marine gradients. We will quantitatively measure microphytobenthic primary production and DOC exudation/mineralization along a coastal fen-shallow water gradient, and its influence by terrestrial compounds, hydrodynamic parameters and sediment transport to... more

B3: Microbial life and the phosphorus cycle along the terrestrial to marine gradient. Along the redox and salinity gradients from coastal peatlands into the Baltic Sea the size and biological availability of the different phosphorus pools are changing. However, the microbial influence on phosphorus cycling along the coastal ecotone is not well understood... more

B4: Factors controlling transport and matter cycling at the sediment-water-interface. We will document the distribution of sediment, peat and glacial clay at the sea floor along with those characteristics relevant for biogenic and hydrodynamic matter exchange. Quantification of oxygen uptake (metabolism) and tracer exchange (fluid transport) will follow... more

B5: Bioenergetics-mediated effects of physical disturbance and salinity stress on benthic macroinvertebrates in shallow coastal waters of the Baltic Sea. We aim at assessing the interactive effects of physical disturbance and salinity stress on activity and bioenergetics of the key bioturbator species, the soft-shell clam Mya arenaria and the lugworm Arenicola marina, and develop a predictive bioenergetically-based model .. more