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Colonialist ideals in an un-colonial place "Terra Australis Nondum Cognita" /Dalke, Samuel S. January 2007 (has links)
Thesis (B.A.)--Haverford College, Dept. of English, 2007. / Includes bibliographical references.
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The classification and structure of marine macrobenthic assemblages at Arthur Harbor, Anvers Island, AntarcticaRichardson, M. D. (Michael D.) 21 July 1976 (has links)
In January-February 1971 five replicate 0.07 m² Van Veen grabs
were obtained from each of 12 stations in Arthur Harbor and nine Van
Veen grabs were obtained from two stations in nearby Bismark Strait.
The 69 grab samples yielded 78,395 individuals which were separated
into 282 taxa, including 108 species of annelids (54.5% of the individuals),
117 species of arthropods (30.3%), 35 species of molluscs
(11.3%) and 22 species in other phyla (4.0%).
The density of macrofauna (17,522 individuals/m²) found in
Arthur Harbor was high compared to other reported areas. This high
density was considered to be the result of high organic input from
phytoplankton, phytobenthos and attached macroalgae, the efficient
utilization of organic matter by macrobenthos and the slow growth rate
of macrobenthic species as an indirect result of cold temperatures.
Diversity values were moderately high with high species richness
values and low evenness values. The high species richness values may be the consequence of seasonal constancy of temperature and
salinity in Arthur Harbor, while low evenness values probably result
from the physical stress of iceberg grounding coupled with high
organic input.
Six macrobenthic assemblages (site groups) and 11 species
groups were found in the study area by classification analysis (Bray-Curtis dissimilarity, group-average sorting). Station groups were
described by dominant species, density and diversity. Species groups
were described by the dominance, fidelity, constancy, and percent
abundance of constituent species restricted to site groups.
The existence of discrete assemblages derived from the classification
analysis was supported by direct ordination. Assemblages
were interpreted to be areas of relative homogeneity which interrupt
a general continuum of distribution of species with depth. The depth
gradient probably represents several factors including increased
constancy of temperature and salinity, lower organic input from
attached macroalgae and phytobenthos, and a reduced incidence of
iceberg grounding. Diversity, species richness, and evenness values
increased with the depth gradient, while density values decreased
with depth.
The dominant species obtained in this study are widely distributed
throughout the Antarctic, and 4% of the 162 taxa identified to species
were also found at Terre Adelie, East Antarctica. Thus assemblages found in Arthur Harbor are probably circumpolar.
In spite of the stability of temperature and salinity, Arthur
Harbor macrobenthic assemblages were moderately stressed by
glacial activity Icebergs, which often ground in Arthur Harbor,
destroyed the benthos by crushing and churning the sediment. The
disturbed area was first repopulated by motile, opportunistic species.
These species fed on macroalgae which collected in the depression
left by the iceberg. Scavengers and carnivores appeared later to feed
on the grazers and macrofauna destroyed by iceberg grounding.
Within a year the depression filled, and typical meiobenthic assemblages
were re-established. Several years may be required before
macrobenthic assemblages are re-established. Station 8, located
near the glacial face had the lowest values of diversity, species
richness, evenness, and density of any station in Arthur Harbor.
These low values resulted from physical stress of glacial calving.
Large pieces of ice calved from the glacial face and crushed the sediment
by impact with the bottom. The waves created by impact of the
calved ice with the water also disturbed the sediment creating an
unstable sediment surface. / Graduation date: 1977
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Magma ascent and redox evolution at Erebus volcano : observational and experimental constraintsMoussallam, Yves January 2013 (has links)
No description available.
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Biosecurity at the Extreme: Pathways and Vectors between New Zealand and Scott Base, AntarcticaFortune, Adrienne L January 2006 (has links)
Biosecurity is one of the main mechanisms used to protect and mitigate the introduction of non-indigenous species. Effective biosecurity requires a knowledge and understanding of pathways and vectors along which invasion can occur. This study contributes to our knowledge and understanding of possible biosecurity risk factors in the Antarctic by identifying potential vectors for invasive species in the pathway between New Zealand and the Antarctic. The Antarctic has important indigenous terrestrial and marine, plant and animal species, all of which contribute to the food chain in Antarctica and the Southern Ocean. This study seeks to contribute some baseline data about pathways and vectors between the two regions and the implications for the biosecurity of both. An assessment of some of the risks associated with human activities within the Antarctic region, including the traffic of people and goods to and from the area, are the focus of this thesis. Current biosecurity practices with regard to personnel, shipping containers, and fresh produce are examined and where appropriate, recommendations to alleviate any detected risks are made. The results of the research indicate a significant volume of seed and plant material being unintentionally transported to Antarctica. The most striking finding was the presence of seeds in new clothes, which have previously been assumed not to be vectors. The presence of seeds in soil samples in Antarctica suggests that seeds have probably already been transported to Antarctica. Presently the climate in Scott Base seems to prevent non-indigenous species from becoming established. However, with the increases in temperature being experienced in Antarctica, this may not always be the case, therefore greater attention to biosecurity legislation and its implementation is required.
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The politics of international collaboration in polar researchSchild, Ingrid January 1996 (has links)
No description available.
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The tectonic history of the Ruker Province, southern Prince Charles Mountains, East Antarctica: implications for Gondwana and RodiniaPhillips, Glen Unknown Date (has links) (PDF)
Within the Ruker Province of East Antarctica, there is evidence for several key geological events that have occurred coincidently with periods of dynamic earth evolution. A detailed evaluation of the tectonic history of the region is therefore required. This research focuses on the tectonic development of the Ruker Province. The main aspects of this research can be summarised as follows: (1) an evaluation of the gross crustal architecture of the region through the development of a new stratigraphic and structural framework; (2) new U-Th-Pb (LA-ICPMS) age data from detrital zircon grains extracted from thick metasedimentary units that comprise a major component of the Ruker Province; (3) new 40Ar/39Ar data from metamorphic minerals to determine the cooling history of the province; (4) mineral equilibria modelling of metamorphic mineral assemblages to constrain pressure-temperature (P-T) conditions during key orogenic events; (5) a kinematic analysis of brittle/ductile deformation features. Ideas developed from these new data provide inferences on the assembly and dispersion of the late Proterozoic super-continents Rodinia (c. 1000 Ma) and Gondwana (c. 500 Ma).
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Dynamics of the Antarctic mesosphere /MacLeod, R. I. January 1986 (has links) (PDF)
Thesis (Ph. D.)--Mawson Institute for Antartic Research, University of Adelaide, 1987. / Addendum inserted. Includes bibliographical references.
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An ASTER digital elevation model (DEM) for the Darwin-Hatherton glacial system, Antarctica : a thesis submitted in partial fulfillment of the requirements for the degree of Master of Science in Geography in the University of Canterbury /Smith, Nita Jane. January 2007 (has links)
Thesis (M. Sc.)--University of Canterbury, 2007. / Typescript (photocopy). Includes bibliographical references (p. 70-75). Also available via the World Wide Web.
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Intergranular water and permeability of the Lake Vostok accretion ice, Eastern AntarcticaJepsen, Steven Michael. January 2005 (has links) (PDF)
Thesis (Ph. D.)--Montana State University--Bozeman, 2005. / Typescript. Chairperson, Graduate Committee: Edward E. Adams. Includes bibliographical references (leaves 129-136).
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La antártida chilena o, Territorio chileno antártico /Pinochet de la Barra, Oscar. January 1944 (has links)
Originally presented as the author's thesis, Universidad de Chile, Santiago, 1944. / Includes bibliographical references (p. [203]-209).
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