Project Details
Projekt
Trace elements and metal isotopes: Transformation and fractionation
Subject Area
Oceanography
Term
since 2021
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 431491505
DynaDeep Phase 2 will address new research questions that evolved during Phase 1 at our core field-site Spiekeroog (southern North Sea, Germany) to unravel the functionality and relevance of marine-terrestrial interactions below high-energy beaches. To reach this goal, seven subprojects will cooperate in joint field campaigns as well as experimental work and use mathematical models in an integrative approach. Subproject P4 will assess metal transformations at specific hot spots and during ‘hot moments’ of biogeochemical variability in the deep and dynamic subterranean estuary (STE) of the Spiekeroog beach and challenge the transferability of observed reaction zones, biogeochemical processes and dynamics at two other high-energy beach sites. To achieve these goals, we will participate in regular and event-specific field campaigns on Spiekeroog and two validation sites in France and Belgium. We will conduct targeted laboratory experiments to identify trace metal behaviour and isotope fractionation during re-oxidation of reduced metal species and hence characterise the trace metal and isotope signatures communicated to the coastal ocean. We hypothesise, that the general distribution of trace metal reaction zones and biogeochemical processes affecting metal mobility and fractionation found on Spiekeroog, that will be further constrained on specific spatio-temporal scales in Phase 2 of DynaDeep, are transferable to other high-energy beach sites. We will use trace metal concentrations (Fe, Mn, Co, Mo, Re, Tl, U, V) and stable isotopes (Mo, Fe, S, O) in groundwater and reactive solid phases to decipher metal transformations and to disentangle the biotic and abiotic processes controlling trace metal mobility. Ancillary parameters essential for the assessment of the overall STE functionality and dynamics, such as major ions, electric conductivity, nutrients, O2, pH, alkalinity, H2S, as well as the mineralogy and geochemical composition of the solid phase, will be determined by this subproject and made available to the entire research unit.
DFG Programme
Research Units
