The world's tundra regions can be considered as the last unexploited terrestrial biome on the earth's surface. Bryophytes contribute significantly to primary production and nutrient cycling in tundra habitats but received considerably less attention than the vascular plants during research for the Tundra Biome Project of the International Biological Programme in the 1970s. The IBP synthesis recognised this and called for more bryophyte production data and improved methodology in future studies. The synthesis also identitied the need for more information on within-site variability, energy/chlorophyll relationships and mineral nutrient studies where tundra bryophyte production patterns are concerned. Marion Island in the sub-Antarctic has an oceanic "tundra" type of vegetation, and the island offers the characteristics of an ideal "natural laboratory" for conducting fundamental ecological research particularly in the field of primary production and energy flow. Studies at Marion Island paralleled those of the IBP but also concentrated on the vascular component of the vegetation. Bryophytes contribute up to 60% of the biomass and 90% of plant cover in the mires that dominate the well-vegetated coastal plain of Marion Island. Following the termination of IBP research therefore it was decided to extend these studies during the 1980s by measuring growth and characterising the major factors influencing growth patterns in Marion Island bryophytes. In this thesis information is given on the physical and biotic environment of Marion Island. Data is presented on the cover, biomass, seasonal and annual production values, and turn-over rates (decomposition) of 15 bryophyte species found across the full range of habit at types at Marion Island. An analysis is also made of growth-associated variables viz. soils, climate, plant energy, chlorophyll. water and mineral nutrient contents. Production was found to be related broadly to moisture-related variables, overlain by nutrient factors in some instances. Higher absolute production figures were obtained than at other tundra sites and interesting phenological data are discussed. The results suggest that decomposition is controlled mainly by tissue degradability factors and that decomposition is more significant than production in controlling biomass accumulation. A model is given for production/decomposition patterns across the range of habitat conditions at Marion Island. Several growth measurement techniques were tested and recommendations are made concerning methodology for future bryophyte production studies. By reference to ecological data collected during the study.

This study aims to uncover the synoptic weather circulation pattern which is associated with the occurrence of needle ice, snowfall and the zero-curtain effect. The method of study was done through an intensive ground climate measurement campaign from April 2008 to May 2009 with a temperature logger installed throughout the recording period. Results from data analyses indicate that the complex changes in climate parameters may lead to an equally complex response in terms of spatial soil frost dynamics and its direct and indirect effects on soil sediment displacement and ecosystem dynamics. Field evidence in the study suggests that on Marion Island needle ice developed in temperatures as high as -0.2 ºC in strong winds. This confirms that the wet environment of Marion Island, which is dominated by diurnal soil frost is fundamentally different from seasonal frost and permafrost environments. The scoria material is susceptible to needle ice growth and the compacted soil alters the micro-climatology of the affected area making it more susceptible to the formation of needle ice. Soil moisture for needle ice formation and growth is provided by the misty conditions associated with the advent of the cold front (pre-cyclonic). Furthermore, observations of needle ice on Marion show that needles are mostly clear with no sediment inclusion. This is indicative of needle ice formation that has not been interrupted by a shortage of moisture. The zero-curtain effect on Marion Island can occur either as a response to the thawing of the soil after the seasonal freeze. The synoptic assessment of snowfall on Marion Island indicates that; snowfall is associated with the passage of a cold front linked to a strong meridional system of low pressure just south of the island.

No description available.

<p> A sequence of metasedimentary rocks comprising the Prince Albert Group, within and to the southwest of the Ellice Hills, District of Keewatin, N.W.T., was studied. Petrographic examination of the four major facies present -- quartzites, greywacke-paragneisses, metaultrabasics and iron formation was carried out and geochemical whole rock data was obtained using X.R.F. methods. </p> <p> Metamorphism occurred during the Hudsonian orogeny and came in three distinct pulses. These pulses are evident in thin section. The first pulse is characterized by the fonnation of garnet poikiloblasts and a biotite foliation; the second by a stronger biotite and hornblende foliation accompanied by quartz and muscovite porphyroblasts, and the third pulse is characterized by the growth of fibrolite needles. The last pulse of metamorphism shows that fibrolite and orthoclase formed from the dehydration of muscovite in the presence of quartz. Thus, a pressure and temperature regime for this event can be inferred from published experimental studies. These indicate that PM2O ranged from 2.0 to 3.5 Kbars and that temperature ranged from 640° ± l0°C to 670° ± l0°C. Previous pulses may have had higher pressure ranges but certainly lower temperature ranges prevailed. The present metamorphic grade of the Prince Albert Group displays mineral assemblages indicative of the Sillimanite-orthoclase-almandine Subfacies of the Almandineamphibolite Facies as defined by Winkler (1967). </p> <p> Structural deformation is closely associated with metamorphism. At least three periods of deformation have occurred. The first is evident in thin section by the s1 foliation and parallel trains of sialic material in garnet poikiloblasts. The second period of deformation caused the rotation of the above garnets, plus formation of the F2 isoclinal folds, s2 biotite foliation, crenulation of the s1 foliation and the formation of muscovite-quartz porphyroblasts. The third period of deformation is responsible for the F3 folding, warping of the F2 axial trace and the antisotropic growth of fibrolite.</p> / Thesis / Bachelor of Science (BSc)

No description available.

Genetic diversity of two salmonid species, Dolly Varden (Salvelinus malma) and coastal cutthroat trout (Oncorhynchus clarki clarki) in Prince William Sound, Alaska were examined at multiple spatial scales with three molecular markers. Pleistocene glaciers covered what is now Prince William Sound 8,000- 12,000 years ago and both species colonized the region subsequently. Because these species have different migratory behavior and historic ranges I expected to see different patterns of genetic diversity within Prince William Sound. Haplotype frequency and nucleotide diversity in sixteen mitochondrial DNA (mtDNA) restriction fragment enzymes combinations in Prince William Sound were higher in Dolly Varden than in coastal cutthroat trout, which were close to fixation. Low estimates of these measures in coastal cutthroat trout may reflect a founder effect resulting from colonization of this region from a single glacial refuge (Cascadia) and low dispersal capacity. To examine if genetic diversity in coastal cutthroat trout was higher in areas of glacial refuge, three additional locations from throughout their distributional range were examined with the same restriction enzymes. Haplotype frequency and nucleotide diversity were lower in areas that were glaciated than estimates of the same measures in a glacial refuge. Again, founder effects during colonization of the three glaciated sites may account for these results. Genetic variation of Dolly Varden and coastal cutthroat trout was also examined within and among populations in Prince William Sound with microsatellites and allozymes. The pattern of genetic variation in coastal cutthroat trout was complex. There was lower genetic diversity within populations that were recently colonized following recent de-glaciation (150-350 ybp). Genetic diversity among some coastal cutthroat trout populations was high, which possibly reflects restricted migration. In other trout populations there was low diversity among populations, possible reflecting historic gene flow. In Dolly Varden, genetic variation among anadromous populations in Prince William Sound was low. There were large differences among resident and anadromous populations. These data provide information for the management for both species, which may reduce the risk of the loss of genetic diversity within local populations. / Graduation date: 2003

No description available.

No description available.

A língua geral amazônica (LGA), língua de base tupi, chamada em meados do século XIX de nheengatu (nheenga língua + katu bom, boa), foi mais falada que o português em toda a Amazônia até o término do século XIX. Após uma série de fatores que levaram ao seu enfraquecimento, hoje se concentra na região do Alto Rio Negro, onde é língua oficial do município de São Gabriel da Cachoeira AM. Por ser uma língua historicamente veiculada pela oralidade e pela ainda tímida elaboração de materiais para seu estudo e divulgação, iniciativas relacionadas à tradução ao nheengatu mostram-se como estratégias interessantes a favor da revitalização dessa língua e da contribuição para a consolidação de um registro escrito na mesma. Insere-se nesse contexto a tradução do livro Le Petit Prince, de Antoine de Saint-Exupéry, do francês ao nheengatu. O registro escrito adotado em minha proposta de tradução foi estabelecido com base nos textos em e sobre o nheengatu produzidos entre a segunda metade do século XIX e a primeira do século XX e no confronto desse período com a língua em seu estado atual. Além de aumentar o número de materiais escritos na língua, utilizados principalmente no ambiente escolar amazônico, a tradução proposta nesta dissertação vem acompanhada de uma seção em que apresento comentários a respeito das escolhas tradutológicas adotadas por mim, que se relacionam a aspectos linguísticos e culturais envolvidos no processo tradutório. Com o propósito de contribuir não apenas para o fortalecimento do nheengatu, as discussões sobre questões teóricas e modalidades de tradução também podem se somar às contribuições no campo dos Estudos da Tradução. / The Amazon general language (AGL), a language based on Tupi, known as Nheengatu in the mid XIX century (nheenga language + katu good), was more broadly used than Portuguese in the Amazon area until the end of the XIX century. After a series of factors that led to its weakening, the language now is concentrated in the Alto Rio Negro area, where it is established as the official language of the São Gabriel da Cachoeira town, in the state of Amazonas. Since it is a language that has been historically used orally and the development of materials to study and disclose it is still stagnant, measures related to the translation into Nheengatu have proved to be interesting strategies favoring the revitalization of the language and the contribution for a consolidation of a written register in it. In this context we find the translation of Antoine de Saint-Exupérys book, Le Petit Prince, from French to Nheengatu. The written register adopted in my translation proposal was established based on texts in Nheengatu, and about the language, produced between the second half of the XIX century and the first half of the XX century and the confrontation in this period with the language in its current state. Besides increasing the quantity of material written in the language, used mainly in the Amazon school environment, the translation put forth in this dissertation comes with a section in which I present comments concerning of the translation choices I adopted, which relate to linguistic and cultural aspects involved in the translation process. Aiming at contributing not only to strengthen the Nheengatu language, the discussions on theoretical matters and translation modalities may also add to the contributions to the Translation Studies field.

Breeding habitat of Harlequin ducks (Histrionicus histrionicus) was studied in eastern Prince William Sound, Alaska, during 1991 - 1993. Streams in Prince William Sound were surveyed for Harlequin ducks and monitored with mist nets. Physical characteristics of 24 Harlequin breeding streams were compared to those of 24 streams not used for breeding using 2 sample, principal components and logistic regression analyses. Nests were located using radio-telemetry of marked females. Harlequin ducks resident in eastern Prince William Sound selected the largest anadromous salmon streams available for nesting. Volume discharge of breeding streams averaged 3.2 m��/s and was the most important factor in habitat variation between streams used and not used by breeding Harlequins. Expansive estuaries and intertidal deltas present at the outflow of large streams were important foraging and loafing areas of Harlequin ducks. Although nesting females generally avoided smaller salmon streams their intertidal estuaries were often used for foraging by females and molting males. The largest streams in Prince William Sound, glacially fed rivers, were not used by breeding Harlequins. Ten nest sites of Harlequin ducks in eastern Prince William Sound were located on southwest facing, steeply sloping banks of small, first order tributaries near timberline elevation. Nests were associated with woody debris and shrubs, in shallow depressions or cavities, and were beneath the canopy of old growth forest. Microhabitat produced by a southwest aspect, snow shadow provided by the forest canopy, and sloping stream bank may provide nesting sites earlier in the spring compared to surrounding areas. / Graduation date: 1994