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In this study the foraminifera of the glacial erratic Heiligenhafener Kieselgestein (HKG) consisting of siliceous sandstones are documented for the first time. The glacial erratics in northern Germany were deposited during the Pleistocene. The age of the HKG sandstone is indicated as Eocene from 49.6 Ma to 47.8 Ma. The lower limit is given by the f...
Citations
... So far two papers on foraminifera in the Eocene Heiligenhafener Kieselgestein and in Cretaceous chalkmarl smaers at the Baltic coast have been published (Hesemann and Ketelsen 2017;Hesemann 2020). Two papers on foraminifera of the Oligocene Sternberger Gestein and the Jurassic so called "Kelloway Geschiebe" are in the making. ...
The Mlalazi River flows through a natural reserve at the eastern coast of South Africa and has been regarded as free from contamination. To prove it and assess the ecological state of aquatic life in the reserve, as well as to enhance the indicator value of marginal marine Foraminifera and Ostracoda in South Africa, we conducted an analysis of microfauna in 25 surface sediment samples. These samples were obtained from the Mlalazi estuary, covering a salinity range from oligohaline to euhaline. Except of two samples, all others contained Ostracoda and Foraminifera. Among the identified ostracod species, there were 17 species belonging to 14 genera. Typical taxa are the brackish water species Perissocytheridea aestuaria, Sulcostocythere knysnaenis, and Australoloxoconcha favornamentata. Our investigation identified 19 Foraminifera species from 16 genera, with dominant taxa such as Ammonia sp., Quinqueloculina sp., and Milliolinella sp. Three distinct assemblages were observed: A) Ammonia sp., Quinqueloculina sp., with very low diversity and abundances in general, located along the river course and exciding Pollution Load Index (PLI); B) Ammonia sp., Quinqueloculina sp., Sulcostocythere knysnaenis with higher salinity and lower PLI; C) Ammonia sp., Quinqueloculina agglutinans, Cribroelphidium articulatum located in mudflats with the most minimal PLI. Our findings align with the commonly observed diversity trend, which indicates reduced species diversity corresponding to elevated pollution levels. Notably, the examined samples revealed a range of Foraminiferal Abnormality Index (FAI) up to 23%, exhibiting anomalies such as multiple tests, changes in coiling, and abnormal chamber shapes. Geochemical analysis indicates that the river is subjected to substantial anthropogenic pressure, as evidenced by elevated concentrations of heavy metals, sulphur, PET, and LDPE. Ongoing investigations in South African estuaries are expanding our dataset and will contribute to a better understanding of the species-specific responses of Ostracoda and Foraminifera to anthropogenic pressure.
