Foraminiferal test abnormalities in the western Baltic Sea

Abnormal tests were commonly found in recent benthic foraminiferal assemblages in two fjords of the Kiel Bay, the western Baltic Sea. We assessed 18 different types of abnormalities, which were classified into five groups: chamber, apertural, umbilical, coiling and test abnormalities. In both fjords, test abnormalities are over-represented in Ammonia beccarii and under-represented in Elphidium excavatum subspecies compared to their average proportions in the living assemblages. We found two species-specific abnormality types that occurred only in Ammonia beccarii: a bulla-like chamber covering the umbilicus and spiroconvex tests. In the outer Kiel and Flensburg Fjords, the highest frequencies of abnormal tests were associated with occasional salt-rich, bottom-water inflows from the Belt Sea. Based on the predominance of megalospheric specimens of living foraminifera, it is suggested that coincidence of salinity changes with a reproduction period might be harmful, especially for young individuals, leading to development of abnormal tests. On the other hand, pollution by heavy metals led to higher percentages of abnormal tests in the inner parts of both fjords. Our data show different relationships between abnormal tests and heavy metals in both fjords due to different hydrographical conditions. Tests of Ammonia beccarii found in the Gelting Bay, the Flensburg Fjord, showed traces of dissolution and development of double tests. Such specific abnormal tests mirror the peculiar environmental setting characterized by changes in salinity and enhanced sediment redeposition. It is concluded that abnormal tests as an indicator of environmental pollution have to be used cautiously in areas with strong environmental instability

3. Wochenbericht M78/1

Können schmelzende Gletscher und heftige Niederschläge in Europa den Golfstrom schwächen? Dieser Frage wollen Kieler Meereswissenschaftler auf der METEOR-Expedition M 78/1 zur Wiege von „Europas Fernheizung“ in der Karibik nachgehen. Die Expedition beginnt am 21. Februar 2009 im Hafen von Colon (Panama) und endet am 28. März 2009 im Hafen von Port of Spain (Trinidad and Tobago). Die Fahrtroute führt zunächst nach Norden in den Golf von Mexiko, an der Nordküste von Kuba entlang und zwischen Kuba und Haiti hindurch wieder nach Süden bis vor das Mündungsdelta des Orinoko. Dabei legt die METEOR unter der wissenschaftlichen Fahrtleitung von Dr. Joachim Schönfeld (IFM-GEOMAR) rund 5200 Seemeilen zurück. FS Meteor Reise M78/1 (Colon, Panama – Port of Spain, Trinidad) 3. Wochenbericht, 2. bis 8. März 200

5. Wochenbericht M78/1

Können schmelzende Gletscher und heftige Niederschläge in Europa den Golfstrom schwächen? Dieser Frage wollen Kieler Meereswissenschaftler auf der METEOR-Expedition M 78/1 zur Wiege von „Europas Fernheizung“ in der Karibik nachgehen. Die Expedition beginnt am 21. Februar 2009 im Hafen von Colon (Panama) und endet am 28. März 2009 im Hafen von Port of Spain (Trinidad and Tobago). Die Fahrtroute führt zunächst nach Norden in den Golf von Mexiko, an der Nordküste von Kuba entlang und zwischen Kuba und Haiti hindurch wieder nach Süden bis vor das Mündungsdelta des Orinoko. Dabei legt die METEOR unter der wissenschaftlichen Fahrtleitung von Dr. Joachim Schönfeld (IFM-GEOMAR) rund 5200 Seemeilen zurück. FS Meteor Reise M78/1 (Colon, Panama – Port of Spain, Trinidad) 5. Wochenbericht, 16. bis 22. März 200

Monitoring benthic foraminiferal dynamics at Bottsand coastal lagoon (western Baltic Sea)

Benthic foraminifera from Bottsand coastal lagoon, western Baltic Sea, have been studied since the mid-1960s. They were monitored annually in late autumn since 2003 at the terminal ditch of the lagoon. There were 12 different species recognised, of which three have not been recorded during earlier investigations. Dominant species showed strong interannual fluctuations and a steady increase in population densities over the last decade. Elphidium incertum, a stenohaline species of the Baltic deep water fauna, colonised the Bottsand lagoon in 2016, most likely during a period of salinities >19 units and water temperatures of 18 °C on average in early autumn. The high salinities probably triggered their germination from a propagule bank in the ditch bottom sediment. The new E. incertum population showed densities higher by an order of magnitude than those of the indigenous species. The latter did not decline, revealing that E. incertum used another food source or occupied a different microhabitat. Elphidium incertum survived transient periods of lower salinities in late autumn 2017, though with reduced abundances, and became a regular faunal constituent at the Bottsand lagoon

1. Wochenbericht M78/1

Können schmelzende Gletscher und heftige Niederschläge in Europa den Golfstrom schwächen? Dieser Frage wollen Kieler Meereswissenschaftler auf der METEOR-Expedition M 78/1 zur Wiege von „Europas Fernheizung“ in der Karibik nachgehen. Die Expedition beginnt am 21. Februar 2009 im Hafen von Colon (Panama) und endet am 28. März 2009 im Hafen von Port of Spain (Trinidad and Tobago). Die Fahrtroute führt zunächst nach Norden in den Golf von Mexiko, an der Nordküste von Kuba entlang und zwischen Kuba und Haiti hindurch wieder nach Süden bis vor das Mündungsdelta des Orinoko. Dabei legt die METEOR unter der wissenschaftlichen Fahrtleitung von Dr. Joachim Schönfeld (IFM-GEOMAR) rund 5200 Seemeilen zurück. FS Meteor Reise M78/1 (Colon, Panama – Port of Spain, Trinidad) 1. Wochenbericht, 19. bis 22. Februar 200

2. Wochenbericht M78/1

Können schmelzende Gletscher und heftige Niederschläge in Europa den Golfstrom schwächen? Dieser Frage wollen Kieler Meereswissenschaftler auf der METEOR-Expedition M 78/1 zur Wiege von „Europas Fernheizung“ in der Karibik nachgehen. Die Expedition beginnt am 21. Februar 2009 im Hafen von Colon (Panama) und endet am 28. März 2009 im Hafen von Port of Spain (Trinidad and Tobago). Die Fahrtroute führt zunächst nach Norden in den Golf von Mexiko, an der Nordküste von Kuba entlang und zwischen Kuba und Haiti hindurch wieder nach Süden bis vor das Mündungsdelta des Orinoko. Dabei legt die METEOR unter der wissenschaftlichen Fahrtleitung von Dr. Joachim Schönfeld (IFM-GEOMAR) rund 5200 Seemeilen zurück. FS Meteor Reise M78/1 (Colon, Panama – Port of Spain, Trinidad) 2. Wochenbericht, 23. Februar bis 1. März 200

Seasonal dynamics and decadal changes of benthic foraminiferal assemblages in the western Baltic Sea (NW Europe)

Living benthic foraminiferal assemblages were monitored between January and July 2004 in the Kiel Bight, Baltic Sea. Phytoplankton blooms and the deposition of organic detritus were depicted by fluorometer hydro casts and pigment concentrations in surface sediments. Three depositional pulses of organic matter were identified by high phytoplankton concentrations above the sea floor and elevated pigment concentrations in the surface sediment. The foraminiferal assemblage composition remained rather constant but the population density of Elphidium excavatum clavatum showed a two- to six-fold increase within a few days after organic detritus deposition. The foraminiferal assemblage composition was compared to earlier studies in this area. Elphidium excavatum, Ammotium cassis and E incertum dominated the living fauna in the 1960s and 1970s. The recent survey revealed a predominance of E. excavatum subspecies (more than 90% of the living assemblage). The average population densities were six times higher than in the 1970s. Data structure and model calculations suggested that E excavatum clavatum is able to reproduce rapidly, with high offspring numbers at elevated food supply. The diminution of A. cassis has occurred in Kiel Bight during the last ten years and was most likely induced by a period of low deep-water salinities in the early 1990s

Pleistocene to Holocene benthic foraminiferal assemblages from the Peruvian continental margin

The benthic foraminiferal inventory and their assemblage composition was documented along five sediment cores from the Peruvian margin between 3°S and 18°S at water depths of 500 to 1250 m, covering the lower boundary of today’s Oxygen Minimum Zone (OMZ). Emphasis was given to certain time intervals during the last 22 thousand years when different climatic and oceanographic conditions prevailed than today. In total three agglutinated and 186 calcareous species were recognised. Bolivina costata, Bolivinita minuta, Cassidulina delicata and Epistominella exigua were most abundant. The foraminiferal distributions revealed a marked change in assemblage composition particularly at the deeper cores during and after the deglaciation. The diversity declined and Bolivina species became dominant. These changes took place gradually over several millennia, and high-frequency fluctuations were not recorded. This pattern provides evidence for rather stable ecological conditions and sluggish changes in bottom water circulation during the last deglaciation

Checklist, assemblage composition, and biogeographic assessment of Recentbenthic foraminifera (Protista, Rhizaria) from São Vincente, Cape Verdes

We describe for the first time subtropical intertidal foraminiferal assemblages from beach sands on São Vincente, Cape Verdes. Sixty-five benthic foraminiferal species were recognised, representing 47 genera, 31 families, and 8 superfamilies. Endemic species were not recognised. The new checklist largely extends an earlier record of nine benthic foraminiferal species from fossil carbonate sands on the island. Bolivina striatula, Rosalina vilardeboana and Millettiana milletti dominated the living (rose Bengal stained) fauna, while Elphidium crispum, Amphistegina gibbosa, Quinqueloculina seminulum, Ammonia tepida, Triloculina rotunda and Glabratella patelliformis dominated the dead assemblages. The living fauna lacks species typical for coarse-grained substrates. Instead, there were species that had a planktonic stage in their life cycle. The living fauna therefore received a substantial contribution of floating species and propagules that may have endured a long transport by surface ocean currents. The dead assemblages largely differed from the living fauna and contained redeposited tests deriving from a rhodolith-mollusc carbonate facies at <20 m water depth. A comparison of the Recent foraminiferal inventory with other areas identified the Caribbean and Mediterranean as the most likely source regions. They have also been constrained as origin points for littoral to subtidal macroorganisms on other Cape Verdean islands. Micro-and macrofaunal evidences assigned the Cape Verde Current and North Equatorial Current as the main trajectories for faunal immigrations. The contribution from the NW African coast was rather low, a pattern that cannot be explained by the currently available information

Recent benthic foraminiferal assemblages from the Celtic Sea (South Western Approaches, NE Atlantic)

The faunal composition and diversity pattern of Recent benthic foraminifera from the shelf and slope of the South Western Approaches (Celtic Sea) were assessed. The sampling stations cover a depth range from 100 to 500 m. A total number of 294 species was recorded, of which 89 were found exclusively in the living fauna and 118 only in the dead assemblage, whereas 87 species were found in both assemblages. The faunal composition revealed a distinct bisection of the living fauna on the shelf. While certain distribution patterns of living dominant species were recognized along a NE-SW trending transect towards the shelf edge, the living fauna changed within small depth intervals and geographic position on the slope. Causes for this structured slope assemblages were probably along-slope currents of varying strengths, as well as variations in topography and bottom sediments. Analyses of population densities and diversity patterns determined high densities along the shelf edge and at one slope station, as well as an increasing diversity with water depth. A comparison with literature data from the same area yields distinct differences in faunal composition on the shelf and slope. The diversity was similar on the shelf, but higher at corresponding stations on the slope. We conclude that the faunal composition was highly influenced by the time and methods of sampling. In order to obtain consistent results in regional studies, all samples should be taken in a short time interval and by using the same sampling device. In addition, we depicted the influences of environmental parameters on dead faunal assemblages and their consequences for paleoenvironmental interpretations of fossil foraminiferal assemblages