Distribution of microphytobenthic biomass in Martel Inlet, King George Island (Antarctica)

The spatial and temporal variation of microphytobenthic biomass in the nearshore zone of Martel Inlet (King George Island, Antarctica) was estimated at several sites and depths (10-60 m), during three summer periods (1996/1997, 1997/1998, 2004/2005). The mean values were inversely related to the bathymetric gradient: higher ones at 10-20 m depth (136.2 +/- A 112.5 mg Chl a m(-2), 261.7 +/- A 455.9 mg Phaeo m(-2)), intermediate at 20-30 m (55.6 +/- A 39.5 mg Chl a m(-2), 108.8 +/- A 73.0 mg Phaeo m(-2)) and lower ones at 40-60 m (22.7 +/- A 23.7 mg Chl a m(-2), 58.3 +/- A 38.9 mg Phaeo m(-2)). There was also a reduction in the Chl a/Phaeo ratio with depth, from 3.2 +/- A 3.2 (10-20 m) to 0.7 +/- A 1.0 (40-60 m), showing a higher contribution of senescent phytoplankton and/or macroalgae debris at the deeper sites and the limited light flux reaching the bottom. Horizontal differences found in the biomass throughout the inlet could not be clearly related to hydrodynamics or proximity to glaciers, but with sediment characteristics. An inter-summer variation was observed: the first summer presented the highest microphytobenthic biomass apparently related to more hydrodynamic conditions, which causes the deposition of allochthonous material.

Recent benthic foraminiferal distribution and related environmental factors in Ezcurra Inlet, King George Island, Antarctica

This investigation attempts to determine which environmental parameters of the bottom water and sediment control recent foraminifera fauna at Ezcurra Inlet (King George Island, Antarctica), using data collected during four summers (2002/03, 2003/04, 2004/05 and 2006/07). The study revealed that Ezcurra Inlet contain typical Antarctic foraminifera fauna with three distinct assemblages and few differences in environmental parameters. The species Bolivina pseudopunctata, Fursenkoina fusiformis, Portatrochammina antarctica, and Adercotryma glomerata were abundant in the samples. An elevated abundance, richness and diversity were common at the entrance of the inlet at depths greater than 55 m, where the inlet was characterized by low temperatures and muddy sand. In the inner part of the inlet (depth 30-55 m), richness and diversity were low and the most significant species were Cassidulinoides parkerianus, C. porrectus, and Psammosphaera fusca. Shallow waters showed low values of richness and abundance and high temperatures coupled with coarser sediment. In areas with high suspended matter concentrations and pH values associated with low salinity the most representative species were Hippocrepinella hirudinea and Hemisphaerammina bradyi.

Occurrence of organochlorine compounds in Euphausia superba and unhatched eggs of Pygoscelis genus penguins from Admiralty Bay (King George Island, Antarctica) and estimation of biomagnification factors

Polychlorinated biphenyls (PCBs) and organochlorine pesticides are compounds that do not occur naturally in the environment and are not easily degraded by chemical or microbiological action. In the present work, those compounds were analysed in unhatched penguin eggs and whole krill collected in Admiralty Bay, King George Island, Antarctica in the austral summers of 2004-2005 and 2005-2006. The compounds found in higher levels (in a wet weight basis) were, in most of the egg samples, the PCBs (2.53-78.7 ng g(-1)), DDTs (2.07-38.0 ng g(-1)) and HCB (4.99-39.1 ng g(-1)) and after Kruskal-Wallis ANOVA, the occurrence seemed to be species-specific for the Pygoscelis genus. In all of the cases, the levels found were not higher than the ones in Arctic birds in a similar trophic level. The krill samples analysis allowed estimating the biomagnification factors (which resulted in up to 363 for HCB, one order of magnitude higher than DDTs and chlordanes and two orders of magnitude higher than the other groups) of the compounds found in eggs, whose only source of contamination is the female-offspring transfer. (C) 2009 Elsevier Ltd. All rights reserved.

Historical record of polycyclic aromatic hydrocarbons (PAHs) and spheroidal carbonaceous particles (SCPs) in marine sediment cores from Admiralty Bay, King George Island, Antarctica

This paper describes the first results of polycyclic aromatic hydrocarbons (PAHs) and spheroidal carbonaceous particles (SCPs) in sediment cores of Admiralty Bay, Antarctica. These markers were used to assess the local input of anthropogenic materials (particulate and organic compounds) as a result of the influence of human occupation in a sub-Antarctic region and a possible long-range atmospheric transport of combustion products from sources in South America. The highest SCPs and PAHs concentrations were observed during the last 30 years, when three research stations were built in the area and industrial activities in South America increased. The concentrations of SCPs and PAHs were much lower than those of other regions in the northern hemisphere and other reported data for the southern hemisphere. The PAH isomer ratios showed that the major sources of PAHs are fossil fuels/petroleum, biomass combustion and sewage contribution generally close to the Brazilian scientific station. (C) 2009 Elsevier Ltd. All rights reserved.

Chlorinated pesticides, polychlorinated biphenyls and polycyclic aromatic hydrocarbons in the fat tissue of seabirds from King George Island, Antarctica

Antarctic Brazilian Program (PROANTAR)

Arsenic and trace metal contents in sediment profiles from the Admiralty Bay, King George Island, Antarctica

Admiralty Bay (Antarctica) hosts three scientific stations (Ferraz, Arctowski and Macchu Picchu), which require the use of fossil fuel as an energy source. Fossil fuels are also considered the main source of pollution in the area, representing important inputs of major pollutants (organic compounds) and trace metals and metalloids of environmental interest. Accordingly, this work presents the results of As, Cd, Cr, Cu, Ni, Pb and Zn in sediment profiles from Admiralty Bay. The sediment results from Ferraz station were slightly higher than the other sampling sites. The highest contents were observed for Cu and Zn (from 44 to 89 mg kg(-1)). Otherwise, by using enrichment factors and geochronology analysis, the most relevant enrichment was observed for As in the samples collected close to the Ferraz station, indicating that increasing As content may be associated with the activities associated with this site. Published by Elsevier Ltd.

Photo-induced toxicity of anthracene in the Antarctic shallow water amphipod, Gondogeneia antarctica

The photo-induced toxicity of anthracene was investigated as the mortality in Antarctic shallow water amphipod, Gondogeneia antarctica, at different concentrations of anthracene and different periods of exposure to natural sunlight and artificial UVA and UVB radiations. When exposed to natural sunlight, animals contaminated in the dark and placed in clean water or in anthracene solutions showed different degrees of mortality, dose-time dependent. Effects were even more evident when these animals were exposed to artificial UVA or UVB radiations. Depuration seemed to be a slow process. The effects of UV radiation and anthracene alone and the effects of the interactions of these two stressors implied that solar radiation is an important parameter that deserves consideration in the environmental assessment of polycyclic aromatic hydrocarbons in Antarctic coastal waters. G. antarctica proved to be a good bioindicator for the phototoxicity of anthracene in Antarctic shallow waters.

Results from a 15-year study on hydrocarbon concentrations in water and sediment from Admiralty Bay, King George Island, Antarctica

Admiralty Bay on the King George Island hosts the Brazilian, Polish and Peruvian research stations as well as the American and Ecuadorian field stations. Human activities in this region require the use of fossil fuels as an energy source, thereby placing the region at risk of hydrocarbon contamination. Hydrocarbon monitoring was conducted on water and sediment samples from the bay over 15 years. Fluorescence spectroscopy was used for the analysis of total polycyclic aromatic hydrocarbons (PAHs) in seawater samples and gas chromatography with flame ionization and/or mass spectrometric detection was used to analyse individual n-alkanes and PAHs in sediment samples. The results revealed that most sites contaminated by these Compounds are around the Brazilian and Polish research stations due to the intense human activities, mainly during the summer. Moreover, the sediments revealed the presence of hydrocarbons from different sources, suggesting a mixture of the direct input of oil or derivatives and derived from hydrocarbon combustion. A decrease in PAH concentrations occurred following improvement of the sewage treatment facilities at the Brazilian research station, indicating that the contribution from human waste may be significant.

Nuculidae (Bivalvia) in the Cape Melville Formation, King George Island, Antarctica, with an overview of the bivalve fauna

Nuculid bivalves of the Cape Melville Formation (Early Miocene, King George Island) are reviewed. Ten bivalve taxa are listed from the formation in the families Nuculidae (two species), Sareptidae, Malletiidae, Limopsidae (two species), Limidae, Pectinidae, Hiatellidae, and Periplomatidae. The Nuculidae consist of two species of Leionucula Quenstedt, 1930. One of these, L. melvilleana n. sp., is described and the other consists of the two species named previously by Anelli et al. (2006), which are demonstrated to be synonymous and are assigned to the species Leionucula frigida (Anelli, Rocha-Campos, Santos, Perinotto & Quaglio 2006). This assemblage, dominated by protobranchs (89% of specimens), is a typical fauna of offshore soft substrates, with a few specimens transported from hard substrates nearby. The diversity of Nuculidae has decreased in the Antarctic region through the Cenozoic.

Monitoring Ice Velocity Field in Victoria Land (Antarctica) Using Cross-Correlation Techniques on Satellite Images