Comparison of trace heavy-metal levels from monitoring in the German Bight and the southwestern Baltic Sea

Since 1973, monitoring for selected trace heavy metals has been performed in the German Bight (North Sea) and the western Baltic Sea. This paper deals with a set of filtered and unfiltered samples from a network of 22 stations covering the whole German Bight based on a cruise with RV “Gauss” in May 1974, and a similar series of samples taken at different depths at 18 stations in the Baltic Sea in October 1974. The metals Cd, Cu, Fe, Mn, and Ni were determined by flameless atomic absorption spectrometry. Data comparison is facilitated since sampling and analytical methods were identical. Distributions of metal-content data have been calculated from unfiltered and filtered samples. Qualitative and semi-quantitative aspects of the major differences or similarities between the histograms obtained from both sea areas are discussed.