Submitted by Francine Silva (francine.silva@unipampa.edu.br) on 2016-09-16T14:48:23Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Comunidade vegetais de áreas de degelo da Ilha Half Moon, Arquipélago das Shetlands do Sul, Antártica.pdf: 769779 bytes, checksum: 794a3b4b95c7a64c38ab5708c8c281b2 (MD5) / Made available in DSpace on 2016-09-16T14:48:23Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Comunidade vegetais de áreas de degelo da Ilha Half Moon, Arquipélago das Shetlands do Sul, Antártica.pdf: 769779 bytes, checksum: 794a3b4b95c7a64c38ab5708c8c281b2 (MD5) Previous issue date: 2015-07-28 / Este trabalho apresenta os resultados do estudo das comunidades vegetais de áreas de degelo realizado durante os verões austrais de 2013/2014 e 2014/2015, nos meses de fevereiro e março, na Ilha Half Moon, no Arquipélago Shetlands do Sul, Antártica Marítima, com o objetivo de avaliar a distribuição e abundância de musgos e líquens, bem como para descrever e mapear as comunidades de plantas que ocorrem na área. As plantas foram correlacionadas com a ocorrência de aves marinhas, relevo e umidade para entender sua influência sobre a distribuição de plantas. Para aferir as comunidades existentes na ilha através da fitossociologia e quantificar as espécies com maior significância ecológica (IES) foi utilizada a metodologia de quadrados (20 x 20cm) de Braun-Blanquet adaptado às condições Antárticas. Para o mapeamento da área foi utilizado o DGPS Astech Promark II®, com precisão sub-metrica e posteriormente processados no software Astech Solutions®. Foram identificadas 37 espécies de briófitas, 59 liquens, uma angiosperma, a Deschampsia antarctica Desv., e duas espécies de algas macroscópicas. Foram dispostos 358 quadrados e identificadas cinco comunidades vegetais na ilha, distribuídas de acordo com a ocorrência de animais e a influência marítima. As comunidades descritas foram as seguintes: Comunidade Liquens fruticulosos, Comunidade carpete de musgos, Comunidade de Liquens Muscicolas, Comunidade de Liquens crustosos e Comunidade Turfa de musgos. A espécie que apresentou o IES mais elevado da ilha foi Sanionia uncinata (Hedw.) Loeske aparecendo em 71.78% dos quadrados amostrados. A comunidade que apresentou maior número de espécies foi a Carpete de musgos e a mais diversa foi a comunidade liquens crustosos, que tem sua maior parte localizada na área onde estão as colônias de pingüins. / This paper presents the results of the study of plant communities of free ice areas conducted during the austral summer of 2013/2014 and 2014/2015, in February and March, on Half Moon Island in the South Shetlands Archipelago, Maritime Antarctica, aiming to evaluate the distribution and abundance of mosses and lichens, as well as to describe the plant communities occurring in the area, with mapping of the vegetation communities. To assess existing communities on the island through the phytosociology and quantify the species with the highest ecological significance (IES) was used the methodology square (20 x 20cm) of Braun-Blanquet adapted to Antarctic conditions. . The area was mapped using an Astech Promark II® DGPS, yielding sub-metric precision after post-processing with Astech Solutions® software. The number of species totalized 38 bryophyte species, 59 lichens, only one flowering plant (Deschampsia antarctica Desv.) and two macroscopic terrestrial algae. Five plant communities were identified in the island, distributed accordingly to animal occurrence and to sea influence. The plant communities were described as follows: Fruticose lichens community, Moss-carpet community, Muscicolous Lichens community, Crustose lichens community and Moss turf community. The species with the highest IES of the island was Sanionia uncinata (Hedw.) Loeske appearing in 71.78% of sampled squares. The community with the highest richness species was the Moss Carpet, and the most diverse community was the crustosos lichens, which has mostly located in the area where the penguin colonies.

Polybrominated diphenyl ethers (PBDEs) are anthropogenic chemicals whose environmental behavior is similar to the well-known polychlorinated biphenyls (PCBs). Few studies have quantified the amount and distribution of PBDEs in the southern hemisphere and Antarctica. The analyses reported in this dissertation document the levels of PBDEs in lichens, mosses and seabird eggs collected at King George Island, Antarctic Peninsula. The analyses were carried out using Gas Chromatography/Electron Impact-Mass Spectrometry (GC/EI-MS). Employing the ion stacking technique lowered detection limits and ensured instrument selectivity and sensitivity to the compounds of interest. Lichens and mosses absorb PBDEs directly from the atmosphere and their contamination indicates that long-range transport is the primary source of these chemicals to King George Island. The congener patterns of PBDEs in plants indicate that commercial mixtures of Penta-BDE and Octa-BDE have reached Antarctica. Differences in the levels of PBDEs observed in lichens and mosses are probably due to factors that govern the uptake of PBDEs from the atmosphere. Contamination in lichens showed a positive correlation with local precipitation. Conversely, absorption of PBDEs in mosses appears to be controlled by other plant-specific factors. Marine phytoplankton-derived aerosols are hypothesized to play an important role in the atmospheric transport of PBDEs to the Antarctic environment. PBDEs in south polar skua eggs revealed much higher concentration than in penguin eggs. This is likely associated with the northward migration of these seabirds during the non-breeding season. While penguins reside year-round in Antarctica, south polar skuas migrate northward and can be seen in boreal oceans during the austral winter. Distribution of PBDEs in penguin eggs matches the pattern found in local vegetation suggesting a common source for the chemicals. In contrast, the congener pattern of south polar skuas suggests that birds breeding at King George Island are wintering in the northwestern Pacific Ocean. A potential metabolism of PBDEs in penguin eggs during the incubation period seems to be limited. Most congeners were unaltered from source material in the eggs of chinstrap and gentoo penguins. Low levels of PBDEs, short incubation periods and energy constraints may explain these observations.