ALBERT

Description: The living foraminiferal fauna and associated environmental factors were examined using shallow-water sediment and bottom-water samples collected in the Admiralty Bay (King George Island, Antarctica) during the austral summer of 2004–05. Admiralty Bay has similar environmental characteristics to other Antarctic coastal areas, with bottom water rich in inorganic nutrients and heterogeneous bottom sediments with high concentrations of mud and sand. We found 45 foraminiferal species, including 28 agglutinated and 17 calcareous species. The dominant species were the calcareous Bolivina pseudopunctata and the agglutinated Pseudobolivina antarctica and Portatrochammina antarctica . Only the agglutinated Spiroplectammina biformis was found in all samples. Admiralty Bay contained a typical Antarctic foraminiferal fauna, mainly distinguishable by the type of bottom sediment. We detected two distinct assemblages: (a) from the entrance of the bay area with a main channel, we found an assemblage with relatively high species richness, abundance and diversity, and with abundant Bolivina pseudopunctata and Fursenkoina fusiformis ; and (b) in the inner parts of the three inlets of the bay (Ezcurra, MacKellar, and Martel inlets), mud- and sulfur-rich sediments contained relatively few foraminifers dominated by a few species, mainly of Globocassidulina and Cassidulinoides .

Description: The Santos Estuary, an estuarine system bordering the cities of Santos, São Vicente, and Cubatão in southeastern Brazil, contains the country’s largest harbor and main industrial center that have been impacted by industrial and domestic effluents since the late 19 th century. We report here on the distribution of benthic foraminifera and related environmental parameters in this estuary system during the summer and winter of 2007. The foraminiferal fauna is representative of mixohaline environments, and includes 107 live + dead taxa, of which 73 are calcareous benthic, 33 agglutinated, and one planktonic. Most of the calcareous specimens belong to the genera Ammonia, Elphidium , and Quinqueloculina and the species Nonionella atlantica . The living population was ~10% of the total foraminiferal fauna, and the dominant living species were similar to those in the total live + dead fauna. Ammonia beccarii was dominant in most of the stations during summer and winter. It could be considered opportunistic due to its high abundance in samples with low diversity and richness. It is not evident if the effects of human population density on the study area impacted the distribution of the foraminiferal fauna, because low proportions of deformed tests and low values of abundance, richness, and diversity were also found in pristine areas near Santos, São Vicente, and Cubatão.

Description: Twenty-five surface-sediment samples collected from Martel and MacKellar inlets at Admiralty Bay, King George Island, South Shetland Islands, Antarctica, provided foraminiferal and environmental data to determine if the foraminiferal distribution is affected by melt water from a nearby tidal glacier and other abiotic factors, such as depth, salinity, temperature, grain size, and geochemistry. The foraminiferal assemblages in the two inlets are typical of most shallow Antarctic waters in their composition, low abundance, and low species richness. They consist of species restricted to the Antarctic (e.g., Portatrochammina antarctica , Hippocrepinella hirudinea , and Hemisphaerammina bradyi ) and those that are cosmopolitan (e.g., Globocassidulina biora and G. subglobosa ). Martel Inlet had the richer fauna with 26 species dominated by H. hirudinea and Psammosphaera fusca . In MacKellar Inlet the species H. bradyi was notably more abundant than in Martel Inlet. Globocassidulina biora is an opportunistic species in these variable shallow-water environments, where seasonal warming results in the discharge of glacial meltwater, producing marked fluctuations in salinity and water temperature. Thus, Globocassidulina species are useful for calibrating Recent conditions of temperature and salinity that can be applied to sub-Recent paleoenvironmental reconstruction of climate change.