Impact of a newly-formed periglacial environment and other factors on fresh water chemistry at the western shore of Admiralty Bay in the summer of 2016 (King George Island, Maritime Antarctica)

2018 ◽  
Vol 613-614 ◽  
pp. 619-634 ◽  
Author(s):  
Małgorzata Szopińska ◽  
Danuta Szumińska ◽  
Robert Józef Bialik ◽  
Stanisław Chmiel ◽  
Joanna Plenzler ◽  
...  
2019 ◽  
Author(s):  
Małgorzata Szopińska ◽  
Marek Ruman ◽  
Robert Bialik ◽  
Żaneta Polkowska

2010 ◽  
Vol 23 (1) ◽  
pp. 27-33 ◽  
Author(s):  
Eduardo de Sá Mendonça ◽  
Newton La Scala ◽  
Alan Rodrigo Panosso ◽  
Felipe N.B. Simas ◽  
Carlos E.G.R. Schaefer

AbstractSoil CO2 emission is an important part of the terrestrial carbon cycling and is influenced by several factors, such as type and distribution of vegetation. In this work we evaluated the spatial variability of soil CO2 emission in terrestrial ecosystems of maritime Antarctica, under two contrasting vegetation covers: 1) grass areas of Deschampsia antarctica Desv., and 2) moss carpets of Sanionia uncinata (Hedw.) Loeske. Highest mean emission was obtained for the Deschampsia (4.13 μmol m-2 s-1) developed on organic-rich soil with a strong penguin influence. The overall results indicate that soil temperature is not directly related to the spatial pattern of soil CO2 emission at the sites studied. Emission adjusted models were Gaussian and exponential with ranges varying from 1.3 to 2.8 m, depending on the studied site and vegetation cover.


2007 ◽  
Vol 107 (4) ◽  
pp. 464-474 ◽  
Author(s):  
Isaac R. Santos ◽  
Déborah I.T. Fávaro ◽  
Carlos E.G.R. Schaefer ◽  
Emmanoel V. Silva-Filho

2017 ◽  
Vol 38 (2) ◽  
pp. 231-262 ◽  
Author(s):  
Kazimierz Sierakowski ◽  
Małgorzata Korczak-Abshire ◽  
Piotr Jadwiszczak

AbstractThe paper summarizes results of twenty years of seabird observations carried out between 1977 and 1996 on the western shore of Admiralty Bay (King George Island, South Shetlands, Antarctic). Changes in population size, distribution and phenology of the breeding species as well as the appearance of non-breeding species are reported. A total of 34 species of birds were observed, including 13 breeding species. Among the non-breeding species, four were observed to visit the site regularly, six rarely, and the remaining 11 were observed only occasionally. Among breeding populations, three Pygoscelis penguin species, the main krill consumers, were most numerous. The Adélie Penguin (P. adeliae) dominated among the penguins nesting in the investigated areas, reaching 23,661 breeding pairs in 1978. Two other penguin species were less abundant with population sizes of approximately 7,200 breeding pairs for the Chinstrap Penguin (P. antarcticus) and 3,100 breeding pairs for the Gentoo Penguin (P. papua) in the same year. During the following two decades, breeding populations of pygoscelid species experienced a declining trend and their numbers were reduced by 68.0% for Chinstrap, 67.1% for Gentoo, and 33.9% for Adélie Penguins. The data reported here represent a unique reference basis and provide valuable information about indicator species, suitable for comparison with contemporary observations of bird populations in the Antarctic Peninsula region, a place of rapidly occurring climate changes and intensive harvesting of marine living resources.


2005 ◽  
Vol 17 (3) ◽  
pp. 312-318 ◽  
Author(s):  
CARLOS ALEJANDRO ECHEVERRÍA ◽  
PAULO CESAR PAIVA ◽  
VINÍCIUS COUTO ALVES

Composition and biomass of an Antarctic megafauna community were studied during a discontinuous 12 months cycle (March–December 1999 and December 2000–March 2001) at two stations (12 and 25 m depth) in Admiralty Bay, King George Island, Antarctica. During this period iceberg impacts were monitored in order to analyse their role in structuring the community. Organic matter content of the sediment showed a seasonal cycle for both depths, with lower values during winter and higher in summer. Composition and biomass of the megafauna were comparable to those described in previous surveys for the maritime Antarctica. Interannual or summer/winter changes in the density or biomass of the megafauna community were not significant, although significant differences between depths occurred during the whole survey. The observed community composition can be the considered result of a continuous invasion from a deeper fauna, constrained at shallower waters by the effects of ice and storms.


2021 ◽  
Author(s):  
Jakub Grzesiak ◽  
Aleksandra Woltyńska ◽  
Marek K. Zdanowski ◽  
Dorota Górniak ◽  
Aleksander Świątecki ◽  
...  

AbstractLichens are presently regarded as stable biotopes, small ecosystems providing a safe haven for the development of a diverse and numerous microbiome. In this study, we conducted a functional diversity assessment of the microbial community residing on the surface and within the thalli of Leptogium puberulum, a eurytopic cyanolichen endemic to Antarctica, employing the widely used Biolog EcoPlates which test the catabolism of 31 carbon compounds in a colorimetric respiration assay. Lichen thalli occupying moraine ridges of differing age within a proglacial chronosequence, as well as those growing in sites of contrasting nutrient concentrations, were procured from the diverse landscape of the western shore of Admiralty Bay in Maritime Antarctica. The L. puberulum bacterial community catabolized photobiont- (glucose-containing carbohydrates) and mycobiont-specific carbon compounds (d-Mannitol). The bacteria also had the ability to process degradation products of lichen thalli components (d-cellobiose and N-acetyl-d-glucosamine). Lichen thalli growth site characteristics had an impact on metabolic diversity and respiration intensity of the bacterial communities. While high nutrient contents in lichen specimens from “young” proglacial locations and in those from nitrogen enriched sites stimulated bacterial catabolic activity, in old proglacial locations and in nutrient-lacking sites, a metabolic activity restriction was apparent, presumably due to lichen-specific microbial control mechanisms.


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