Geological mapping of the Heber, Rhüdener Sattel, Northern Germany

This master thesis describes the geological mapping of an 8 km**2 area of the 300 m high elevation HEBER in Northern Germany which is part of the Rhüdener Sattel (Harzvorland). The geology consists of mesozoic rocks from Buntsandstein to Keuper; major parts are Muschelkalk, partly covered with a thin layer of Quaternary loess. The map includes measurements of strike and dip in various outcrops, drafting a scetch of the probable tectonic structure of Rühdener Sattel.

Data Compilation of the Research Vessel METEOR (1964)

In 2008, the 50th anniversary of the IGY (International Geophysical Year), WDCMARE presents with this CD publication 3632 data sets in Open Access as part of the most important results from 73 cruises of the research vessel METEOR between 1964 and 1985. The archive is a coherent organized collection of published and unpublished data sets produced by scientists of all marine research disciplines who participated in Meteor expeditions, measured environmental parameters during cruises and investigated sample material post cruise in the labs of the participating institutions. In most cases, the data was gathered from the Meteor Forschungsergebnisse, published by the Deutsche Forschungsgemeinschaft (DFG). A second important data source are time series and radiosonde ascensions of more than 20 years of ships weather observations, which were provided by the Deutscher Wetterdienst, Hamburg. The final inclusion of all data into the PANGAEA information system ensures secure archiving, future updates, widespread distribution in electronic, machine-readable form with longterm access via the Internet. To produce this publication, all data sets with metadata were extracted from PANGAEA and organized in a directory structure on a CD together with a search capability.

(Appendix) Vertebral number of topsmelt, Atherinops affinis, adults and offspring from different latitudes along the North-American Pacific coast

Organisms that are distributed across spatial climate gradients often exhibit adaptive local variations in morphological and physiological traits, but to what extent such gradients shape evolutionary responses is still unclear. Given the strong natural contrast in latitudinal temperature gradients between the North-American Pacific and Atlantic coast, we asked how increases in vertebral number (VN, known as Jordan's Rule) with latitude would differ between Pacific (Atherinops affinis) and Atlantic Silversides (Menidia menidia), two ecologically equivalent and taxonomically similar fishes with similar latitudinal distributions. VN was determined from radiographs of wild-caught adults (genetic + environmental differences) and its genetic basis confirmed by rearing offspring in common garden experiments. Compared to published data on VN variation in M. menidia (a mean increase of 7.0 vertebrae from 32 to 46°N, VN slope = 0.42/lat), the latitudinal VN increase in Pacific Silversides was approximately half as strong (a mean increase of 3.3 vertebrae from 28 to 43°N, VN slope = 0.23/lat). This mimicked the strong Atlantic (1.11°C/lat) versus weak Pacific latitudinal gradient (0.40°C/lat) in median annual sea surface temperature (SST). Importantly, the relationship of VN to SST was not significantly different between the two species (average slope = -0.39 vertebrae/°C), thus suggesting a common thermal dependency of VN in silverside fishes. Our findings provide novel support for the hypothesis that temperature gradients are the ultimate cause of Jordan's Rule, even though its exact adaptive significance remains speculative. A second investigated trait, the mode of sex determination in Atlantic versus Pacific Silversides, revealed patterns that were inconsistent with our expectation: M. menidia displays temperature-dependent sex determination (TSD) at low latitudes, where growing seasons are long or unconstrained, but also a gradual shift to genetic sex determination (GSD) with increasing latitude due to more and more curtailed growing seasons. Sex ratios in A. affinis, on the other hand, were independent of latitude and rearing temperature (indicating GSD), even though growing seasons are thermally unconstrained across most of the geographical distribution of A. affinis. This suggests that additional factors (e.g., longevity) play an important role in shaping the mode of sex determination in silverside fishes.

Fragmentation and dissolution of benthic foraminifera in Kiel Bight, Baltic Sea, Germany

Early diagenetic ultrastructural alterations of benthic foraminifers of the genera Elphidium and Ophthalmina from the shallow water sediments of the Kiel Bight were investigated by scanning electron microscopy. Pure solution patterns were deduced from supplementary experiments.//Several carbonate destroying processes can be specified by ultrastructural patterns of the shell surfaces. Based on these patterns three zones are established, each showing different mechanisms of shell fragmentation: 1) zone of abrasion, 2) zone of disintegration, 3) zone of corrosion. This zonation depends on the water depth and is caused primarily by water agitation and by under saturation of the bottom water with respect to carbonate.