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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

Seasonal cycles, population dynamics, and production of copepods in the Arctic.

Cairns, Alan Andrew January 1969 (has links)
No description available.
82

The life history of the narwhal, Monodon monoceros l., in the eastern Canadian arctic /

Hay, Keith Alexander. January 1984 (has links)
No description available.
83

Studies in the Arctic plankton, comprising a faunistic survey of certain of the marine planktonic groups collected in the Canadian eastern arctic, and an investigation of the breeding cycles of five of the most important species in the eastern arctic and in west Greenland. --.

Dunbar, M. J. (Maxwell John). January 1941 (has links)
No description available.
84

The circulation and fluxes from the Arctic into the North Atlantic Ocean 1979-2002 model results

Williams, Catherine E. 09 1900 (has links)
Approved for public release; distribution in unlimited. / The recent decreasing trend of sea ice cover in the Arctic region and its projected future reduction has direct implications for the global thermohaline circulation and the U.S. Navy. This thesis provides a qualitative and quantitative analysis of the freshwater export from the Arctic Ocean through the Canadian Arctic Archipelago (CAA) and the Fram Strait into the deep-water formation region of the Labrador Sea, using model data from 1979 to 2002. The results of this thesis directly aid the Navy in preparing personnel, ships, and weapons systems to operate efficiently in a possible ice-free Arctic. A coupled ice-ocean model of the pan-Arctic region at a 1/12-degree and 45-level grid resolution was used to produce data over a 24-year time period. The 24-year averaged annual velocity, temperature, and salinity profiles were compared for each of the analyzed stations. Additionally, 24-year mean monthly volume and freshwater flux time series plots and annual cycle plots were also produced to analyze the region's interannual variability from 1979 to 2002. The results show that the Canadian Arctic Archipelago is the major contributor of freshwater to the Labrador Sea. The CAA is a direct pathway for increased freshwater export from the Arctic into the sub-arctic seas where North Atlantic Deep Water(NADW)forms. The increased freshwater flux through the CAA, found in this study, supports the earlier reports on the freshening of NADW and a possibility of reduction in the meridional overturning rate in the North Atlantic. An increase in freshwater export from the Arctic is a good indicator of increasing sea ice reduction. The predicted opening of the Arctic to commercial and military vessels poses a direct threat to U.S. economical and strategic interests in the Arctic region. This thesis supports the U.S. Navy's ability to operate in a possibly ice-free Arctic. / Ensign, United States Navy
85

Life history of capelin (Mallotus Villosus (Müller, 1776)) and dietary overlap with Arctic cod (Boreogadus saida (Lepechin, 1774)) in the Canadian Arctic

McNicholl, Darcy, McNicholl, Darcy 27 November 2015 (has links)
Capelin (Mallotus villosus (Müller, 1776)) is an important marine forage fish species that typically inhabits sub-Arctic and temperate circumpolar waters. Capelin have recently been reported in greater abundance in Arctic regions, and are considered an indicator for warming climate in the northern marine ecosystem. The goal of this thesis is to examine intrinsic factors among capelin populations, and whether niche overlap among sympatric capelin and Arctic cod (Boreogadus saida (Lepechin, 1774)) will affect the abundance and persistence of capelin in the Arctic as temperatures continue to rise. Life history comparisons of capelin from two Arctic regions (Western Beaufort Sea, Cumberland Sound) relative to a sub-Arctic population (Newfoundland) show that body size, body condition, growth rate and age-at-maturity vary among these regions. Life history characteristics that are adapted to northern environments and increasing temperatures will allow the presence and persistence of this species to increase in the Arctic. The consequence of increased abundance of capelin in the Arctic environment could be competition between capelin and Arctic cod, an Arctic species within a similar dietary niche. Stomach contents indicated that both species feed primarily on calanoid copepods and this result was corroborated with high dietary overlap in isotopic bivariate space (carbon and nitrogen stable isotopes). The occurrence of capelin is expected to increase in the Arctic with rising temperatures, thus adaptation in life history traits in capelin specific to each region may facilitate increased abundance and persistence, and possibly contribute to competitive pressure on Arctic cod. Potential competition will be particularly important in nearshore and shelf habitats where shifts in availability of intermediate trophic level taxa will influence diet and distribution of key predators such as beluga, sea birds, and anadromous fishes. As the Arctic environment changes with climate shifts, newly adapted or dispersed species from sub-Arctic systems are expected to drive shifts in ecosystem structure and function in the marine environment. / October 2016
86

Sex- and Age-Dependent Differences and Habitat Influences on Demersal Arctic Cod, Boreogadus saida (Lepechin 1774) Diet and Energy Allocation in the Canadian Beaufort Sea

Lynn, Brittany 16 September 2016 (has links)
Arctic Cod, Boreogadus saida (Lepechin 1774) occur throughout the circumpolar north at all levels of the water column depending on their life history stage, the time of day, the season, and their activity. Arctic Cod are the most abundant fish species in the Canadian Beaufort Sea (CBS) ecosystem, and are an important link in the flow of energy within the food web. This study examined differences in energy acquisition and usage in Arctic Cod among three depth zones in the CBS (from 15-800m) by examining stomach contents and physiological indicators, taking into account sex, age and body size. Nonparametric comparison analyses found no differences with depth, but support for an ontogenetic shift in diet regarding prey size, a difference in energy content of an average diet between size classes 1 (30-60mm) and 2-4 (2: 60-90mm; 3: 90-120mm; 4: >120mm), and a slight positive relationship between physiological indicators and body size. / October 2016
87

Arctic images 1818-1859

Høvik, Ingeborg January 2013 (has links)
This thesis asks whether there existed a unified view of the Arctic during the time period connected to the high point of British endeavour to find a Northwest Passage, from the first expeditions of the nineteenth-century in 1818 to the return of the last Franklin search party in 1859, forty-one years later. Using this time frame as its marker, the focus of the thesis is primarily on British representations of Arctic landscapes, exploration and Inuit peoples. Through careful empirical analysis of a variety of media, including professional painting, on-the-spot sketches, prints and popular exhibitions, it examines from an art historical viewpoint the historical, political, social and aesthetic contexts in which Arctic representations occurred.
88

Bacterial dynamics in two high arctic lakes.

Morgan, Keith January 1971 (has links)
No description available.
89

Salinity tolerance and osmoregulation of the Arctic marine amphipods Onisimus litoralis (KrÜyer) and Anonyx nugax (Phipps)

Shea, James Robert January 1987 (has links)
No description available.
90

Reproduction and metabolism in Gammurus oceanicus Segerstrale and Gammarus setosus Dementieva.

Steele, V. January 1965 (has links)
With the rapid increase in human population during recent years, a growing interest has developed in the resources of the sea. Although much basic knowledge has accumulated concerning the life in temperate and boreal waters, particularly of the eastern Atlantic, less is known of the fauna and flora of the arctic and subarctic (Dunbar 1953). More information is needed on the standing crops and production rates of the important members of marine ecosystems in the low temperatures of high latitudes, so that production can be evaluated. [...]

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