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Heavy metal pollution originating from anthropogenic sources like mining, industry and ship traffic is becoming an increasing threat for marine life. First evidences for human impacts on the heavy metal concentration in seawater were recorded in medieval times already. An emerging tool for palaeo-environmental applications is the heavy metal concentration in the tests of benthic foraminifera, which enable monitoring of the anthropogenic footprint on recent systems and the fossil record. The Helgoland mud area (HMA) in the German Bight is an important depositional area for fine sediments. Average sedimentation rates of up to 13 mm/yr offer high-resolution archives, which renders the site suitable for studying long-term variations of anthropogenic pollution on the marine system. The HMA also accumulates discharge from the Elbe and Weser rivers, which are affected by mining activities in their catchment areas since the Bronze Age. The concentration of chromium (Cr), manganese (Mn), nickel (Ni), copper (Cu), zinc (Zn), silver (Ag), tin (Sn) and lead (Pb) in tests of Ammonia batava was analysed along a sediment core from the HMA by laser ablation inductively coupled mass spectrometry (LA-ICP-MS). Radiocarbon datings and stable oxygen and carbon isotope stratigraphy revealed that the core is covering the Early Modern Period (~1550–1700 AD) and the post-World War II period (~1958–2009 AD). The basal unconformity of a tempestite depicts a hiatus and non-sequence between both periods ranging from 1700 to 1958 AD. The concentration of Cu, Zn, Ag and Pb was clearly elevated in the post-1950 AD part of the core indicating a markedly higher anthropogenic influence induced by industrialisation and rapid growth of cities since the 1950s. Variations in Cu, Zn, Ni, Ag and Pb concentrations were linked to mining activities and the production rates of Pb and Ag in the Harz Mountains. Redox-sensitive elements like Mn were correlated to storm surges resulting in the extensive reworking of sediment material. Therefore, the chemistry of the tests of A. batava reflects human activities and natural impacts at the same time, which allows its application for unravelling the environmental history of the North Sea and beyond.

The long-term climate cooling during Campanian - Maastrichtian times is not well understood to date, especially because of the uncertainty introduced by low temporal resolution of biostratigraphy and the pronounced provincialism between tropical and temperate taxa. Two new high-resolution carbon isotope records derived from the boreal shelf-sea section at Lagerdorf-Kronsmoor-Hemmoor, northern Germany and the tropical Pacific at Deep Sea Drilling Project Site 305, Shatsky Rise, reduce these uncertainties. The records can be correlated with an accuracy not achieved by biostratigraphic methods so far. Distinct carbon isotope events in the late Campanian and the early Maastrichtian can be identified at both localities suggesting to represent global carbon cycle perturbations. Especially, the negative carbon isotope excursion in the early Maastrichtian, a pronounced feature of open-ocean records from the Pacific and Southern oceans, is recognized for the first time at a shelf-sea locality related to the North Atlantic Ocean. Furthermore, two short-term positive excursions are identified as superimposed signals to this event. The improved stratigraphy provides the unique opportunity to recognize leads and lags between the carbon cycle and ocean circulation of different marine settings and ecosystems, leading to a better understanding of their causes and effects.