Die mittelpleistozäne Flußentwicklung im nordöstlichen Harzvorland: Petrographie, Terrassenstratigraphie

The present study deals with the evolution of the middle Pleistocene river system in the north-eastern foreland of the Harz Mtns. Sediments of the middle fluvial terrace level (early Saalian time) are the main objectives. By using these sediments supplementary with some results of upper fluvial terrace level (early Elesterian time or older) the fluvial palaeogeography within the area has been reconstructed. The sediments were investigated with respect to their gravel spectra, heavy mineral record, sedimentary structures and altitude above the recent river beds. Due to the resulting specifics the sediments have been attributed to particular rivers in the area. Furthermore it is possible to distinguish between fluvial sediments and Elsterian as well as Saalian fluvioglacial deposits. Together with discernible middle or upper terrace characteristics this led to a spatio-temporal reconstruction of the palaeo river system of the Harz Mtns. It revealed that not only during upper terrace sedimentation but even while middle terraces were deposited the rivers partly diversed. These river diversions were mainly caused by hydrodynamic changes reflecting interaction of the fluvial system with Elsterian and Saalian ice shield formation in the north. The Rivers Ecker, Ilse, Rammelsbach, Holtemme, Goldbach, Bode, Selke and Eine were affected by this development as follows: Upper terrace level formation: • The Ecker River formerly ran between its recent river bed and that of the Use River in direction to the Großer Fallstein Mtn. • The Use River flowed to the NE towards the Huy Mtn. • The Goldbach River and the Holtemme River mutually ran to the NW south of the Huy Mtn. After uniting with the Use River and Ecker River it ran south of the Großer Fallstein Mtn. Middle terrace level formation: • The Ecker River flowed far more NE. • Near to the Harz Mtns. the Use River flowed more in the E. The tributary junction of the Rammelsbach River was located far more downstream. Thereafter the Use River ran to the N between Huy Mtn. and Großer Fallstein Mtn. to end up flowing in the area of the Großes Bruch. • The Holtemme River kept its course. Its recent tributary the Goldbach River flowed to the NE and joined the Bode River after leaving the Harz Mtn. Range. • The Eine River ran to the NW when passing todays city of Aschersleben. After flowing together with the Selke River in the area of the Seeländerei it became a tributary to the Bode River. • The Bode River within the recent tributary junction of the Holtemme ran far more in the W. In the area of the Espenbruch it flowed eastwards to the Saale River. The following general implications resulted out of the study: • The so called “mixed sediments” sensu Rosenberger & Altermann (1975) have now been interpreted as proximal fluvioglacial deposits. • High altitudes of middle terrace fluvial deposits in the courses of the Ecker River and Use River were formerly assigned to post middle Pleistocene uplift of the Großer Fallstein Mtn. (Feldmann, 2002). The present study suggests that the unusual high altitudes should rather be attributed to post middle terrace level erosion of the shortened Ilse- Rammelsbach river system or fluvioglacial processes below the glacier. • Within the north-eastern foreland of the Harz Mtns. middle terrace level deposits have previously been subdivided by cryoturbation horizons or short-term progradation of Saalian glaciation. This is not supported by own results for the examined area.

Bestandskundliche Untersuchungen an wirtschaftlich wichtigen Grundfischbeständen im Nordost-Atlantik

For many years the assessments of the commercially most important demersal fish stocks of cod, haddock, saithe, redfish and Greenland halibut have annually been carried out by the "Arctic Fisheries Working Group" of ICES. The most important results of the actual assessment are given in this report. It shows that the gadoid stocks of cod, haddock and saithe are in good and stable conditions and that the stocks are harvested within safe biological limits. The stocks of redfish and Greenland halibut are still at a low level and outside safe biological limits. Greenland halibut shows a slightly positive trend in spawning stock biomass, several year-classes and recruitment.

Fischerei und fischereibiologische Untersuchungen im Nordost-Atlantik im 1. Halbjahr 1996

Biological investigations were carried out onboard the commercial freezing trawler "KIEL" off the Norwegian coast in February/March and in the Bear Island area in May 1996. Data will be used as German contribution to the assessments of the ICES "Arctie Fisheries Working Group". Informations about the fishery and the concentrations of cod, haddock, saithe and redfish in the areas between Röst-, Nordvest-, Fuglöy-Bank and Bear Island are given. Length - and age distributions as well as preliminary results of stomach- and gonad investigations are represented.

Zustand und Entwicklung wirtschaftlich wichtiger Grundfischbestände im Nordost-Atlantik

A review of the NE Atlantic stocks of cod, haddock, saithe, redfish and Greenland halibut is given. The results are based on the assessments of the ICES "Arctic Fisheries Working Group" and the critical examination of the ICES "Advisory Committee on Fisheries Managment (ACFM)".

Aktuelle Möglichkeiten und Risiken der Fischerei im Nordost-Atlantik

Vom 24. August bis 02. September 1993 trafen sich in Kopenhagen Wissenschaftler aus Norwegen, Russland, Spanien, Kanada, Grönland und Deutschland, um Bestandsberechnungen (Assessments) für das Jahr 1993 an den Nordost-atlantischen Beständen des Kabeljau, Schellfisch, Seelachs, Rotbarsch und Schwarzen Heilbutt durchzuführen. Für die Bestandberechnungen standen der Arbeitsgruppe Daten des Jahres 1992 aus der kommerziellen Fischerei verschiedener Länder sowie Ergebnisse und Indices norwegischer und russischer Forschungsschiffe zur Verfügung. Die Assessments wurden mit der V.P.A. (Virtual Population Analysis), mit XSA (Extended Survivors Analysis) und der ADAPT-Methode gerechnet. Die wichtigsten Ergebnisse dieser Bestandberechnungen sowie die im November veröffentlichte Stellungnahme des ACFM (Advisory Committee on Fishery Management) sollen im nachfolgenden dargestellt werden.

Die deutsche Fischerei auf Blauleng 1988 im Nordost-Atlantik

Die Blaulengfänge der deutschen Hochseefischerei fielen 1988 auf 318 t. Das ist der niedrigste Stand seit diese Fischart im Institut für Seefischerei bearbeitet wird. 1980 waren noch 13000 t gefangen worden, in den anschließenden Jahren ging der Ertrag kontinuierlich zurück, stieg lediglich 1987 geringfügig an und fiel 1988 dann auf die genannte Menge ab.