Bachelor Thesis

Ostracoda (Crustacea) as palaeonvironmental indicators around the Early Celtic Princely Seat on the Ipf ( Western margin of the Nördlinger Ries, Baden Württemberg, Germany)

In line with an archaeological excavation in the area of the Early Celtic Princely Seat on the Ipf (Western margin of the Nördlinger Ries) ostracods were found in colluvial sediments. More than 3000 ostracod remains out of material samples from six 2-3m deep profiles were analysed taxonomically as well as with regard to ecological aspects to detect possible changes of the land surface and to reconstruct local palaeoenvironments. Thereby a total of 19 ostracod taxa was identified, which are all also known from modern sites. For one of the six profiles an ecological analysis of the conditions prevailing during the sediment deposition was carried out, using criteria according to the classification scheme of Fuhrmann (2006). All species present in this profile were assigned to the following ecological groups: spring fauna, subdivided in species of rheocrenic springs and species of the helo-/limnocrenes, species of the rhithron and species of permanent stagnant waters, also split in species of cooler and species of warmer waters. Potamocypris zschokkei (0,46-18,18%), Psychrodromus olivaceus (0,44-63.64%) and the most common species Ilyocypris inermis (12,33-86,96%) are occurring in every horizon of this profile. These three species are indicators for spring or flowing waters respectively. Thus there is evidence to suggest, that there has never been a pure stagnant water body at the sampled location, but always a biotope permanently drained by fresh, cool water. The fact that the lower beds contain species typical for stagnant waters (Candona candida, Candona sp., Pseudocandona rostrata, Cyclocypris ovum, Cypria ophtalmica, Cyclocypris laevis, Heterocypris incongruens) and those beds close to the top ground surface don’t bear those species suggests that the aquatic habitat has changed from a cooler stagnant water body with high influence of spring-/freshwater or a marshy spring habitat respectively to a pure spring brook or a flowing water with spring influence.