Description: Heavy metal uptake of benthic foraminifera in shelf regions influenced by anthropogenic impacts in terms of removing these potentially harmful metals from the seawater

Description: Heavy metal pollution from anthropogenic sources increasingly influence marine environments and biota because of their toxicity, persistence and bioaccumulation. Especially coastal environments act as natural catchments for anthropogenic pollutants because these areas are highly affected by industry, agriculture and urban sewage runoff. In nearly all natural environments that are harmed by heavy metal pollution, a combination of several pollutants occurs at the same time. In marginal seas and coastal areas, benthic foraminifera are common in meiofaunal associations, and they can be used as biomonitoring tool for changes in environmental parameters like temperature, salinity, or redox conditions. Furthermore, foraminifera take up heavy metals from the seawater and incorporate those into their carbonate shells during calcification. Moreover, foraminifera have a short life cycle and can therefore react immediately to contaminations of the environment. Here, we will present results from culturing studies with Ammonia aomoriensis, Elphidium excavatum and Ammonia batava addressing the relationship of heavy metal concentration in the seawater and in the foraminiferal tests. The partitioning factor between the ambient seawater and the calcium carbonate of the foraminifera is constrained by continuous water monitoring and laser ablation ICP – MS measurements on single chambers grown during the experiment in a manipulated culturing medium. The foraminifera were exposed to a combination of ten different heavy metals over a range of concentrations comparable to current conditions in medium to high pollutedhigh-polluted areas. A correlation between the heavy metal concentration in the culture medium and in the foraminiferal calcite was recognised for several heavy metals (e.g. Cd, Cr, Pb). Once the carbonate/seawater metal partitioning coefficients are constrained with certainty, investigations of the chemistry of benthic foraminiferal shells offer an advanced and reliable method to monitor short-term changes in the concentrations and bioavailability of toxic elements in seawater.

Description: Particular heavy metals e.g. zinc serve as micronutrients for eukaryotic life and play an important role for cellular metabolism, growth of organisms, reproduction and enzymatic activity. They occur naturally in the environment as trace ingredient in soils, water, rocks, plants and animals. However, in higher concentrations, most heavy metals become toxic and have serious hazard effects on marine biota. Furthermore, they are highly persistent in the marine environment and can be hardly degraded by organisms. Especially coastal environments act as natural catchment basins for anthropogenic pollutants because these areas are highly affected by industry, agriculture and urban runoff. Therefore, it is vitally important to assess past spatial and temporal distribution patterns and to compare those with recent pollution in order to evaluate contemporary emission reduction measures. An emerging paleo-tool is the heavy metal incorporation into foraminiferal shells calcite, which offers monitoring of anthropogenic footprints on the environmental system. Heavy metal records in foraminiferal tests along a sediment core from the North Sea track pollution events of local (e.g. shipyard, ironworks and metallurgy) and global (e.g. market cycles) origin. We analysed the heavy metal concentrations in tests of Ammonia batava (Mn, Zn, Cd Cu etc.) by laser ablation ICP – MS measurements. These metals reveal the pollution history of the North Sea during the last 500 years with focus on the Early Modern Period.

Description: Heavy metal pollution originating from anthropogenic sources, e.g. mining, industry and extensive land use, increasingly influence tropical marine environments. The elevated input of heavy metals into the marine system potentially affects the biota because of their toxicity, persistence and bioaccumulation. Corals are increasingly used as an indicator for reconstructions of past dynamics of environmental factors like temperature or carbonate system parameters. Especially the massive scleractinian coral Porites provides an excellent tool for reconstructions because of their wide distribution (e.g. Great Barrier Reef, Caribbean, Australia or the tropical region of the Indo – Pacific) and because of their high growth rates allowing measurements at sub - annual resolution as well as building environmental archives covering hundreds of years. Furthermore, recent studies demonstrated that the trace metal concentration in the coral skeleton is most likely linked to local (or global) seawater chemistry including contaminations at various scales. Therefore, the metal concentration in the coral skeleton offers the opportunity of monitoring the spatial and temporal distribution patterns of heavy metals in the environment so contemporary emission reduction measures can be evaluated. Here we will present the final results of culturing studies addressing the relationship of heavy metal concentrations in the seawater and those in the coral skeleton. The partitioning factor between the ambient seawater and the aragonite of the corals is constrained by continuous water monitoring with weekly to biweekly sampling intervals and laser ablation measurements of grown skeleton. Culturing experiments with Porites lobata, Porites lichen, Montipora sp., Seriatopora sp. and Stylophora sp. are performed. The concentrations of heavy metals in the culturing medium are increased in four phases by a factor between 5 and 10 over a time period of more than a year. The results will facilitate a new way to monitor anthropogenic footprints in presumably pristine tropical environments as well as areas of high human impact.