Biogeographic distributions and environmental controls of stream diatoms in the Canadian Arctic Archipelago

Botany ◽  
2009 ◽  
Vol 87 (5) ◽  
pp. 443-454 ◽  
Author(s):  
Dermot Antoniades ◽  
Marianne S.V. Douglas ◽  
John P. Smol

Streams are amongst the most sensitive ecosystems in Arctic regions to environmental change. Although diatoms are excellent indicators of environmental change, little information is available about stream diatom distributions across the vast Canadian High Arctic. We sampled 42 streams from nine islands in the Canadian Arctic Archipelago to study their diatom floras and evaluate the influences of biogeographic and environmental variables on species distributions. Highly divergent diatom communities were identified, with 100% species overturn between the most dissimilar communities. Taxa including Hannaea arcus (Ehrenberg) Patrick were characteristic of streams from all regions; other common taxa included Nitzschia perminuta (Grunow) Peragallo, Rossithidium petersenii (Hustedt) Round & Bukhtiyarova, Achnanthidium minutissimum (Kützing) Czarnecki, and Eucocconeis laevis (Østrup) H. Lange-Bertalot. Canonical correspondence analysis indicated that diatom assemblages were significantly related to differences in pH, temperature, latitude, and longitude, which together explained 14.7% of species variability. Analysis of similarities indicated that communities did not differ significantly between epilithic and epiphytic samples and that there were weak but significant differences between the diatom communities in our three regions. These data provide important baseline information for future biomonitoring efforts as well as for paleolimnological studies of past stream hydrology.

1976 ◽  
Vol 16 (74) ◽  
pp. 119-133 ◽  
Author(s):  
Fritz Müller

AbstractThe 10 m temperatures were measured over several years at 16 sites on the White Glacier (lat. 80° N.), Axel Heiberg Island, Canadian Arctic Archipelago. At three sites deep profiles were made using a new drilling technique, reaching a maximum depth of 280 m. Large differences in the 10 m temperatures between locations and from year to year were observed. The deviations of these temperatures from the almost isothermal mean annual air temperature over the glacier are discussed. The heating effect of the melt water in the lower percolation zone was found to be very important. A conceptual model is developed to assess the influence of these irregularities in the energy input at the upper boundary on the thermal regime of the entire glacier. So far a quantitative analysis has been made only for the relatively simple 30 m temperature profile measured on the tongue of the glacier.


1976 ◽  
Vol 33 (8) ◽  
pp. 1667-1670 ◽  
Author(s):  
Irene Lubinsky

The shell morphology and area of distribution of Thyasira dunbari n.sp. is described and illustrated. This species differs from its northern relatives, especially T. gouldi Phil., by its high, bent forward shell, and thin, long edentulous hinge with massive callus. It occurs in the northernmost part of the Canadian archipelago and off East Greenland. It is a high arctic shallow-water species, which seems to be endemic in the Canadian–Greenlandic region.


1972 ◽  
Vol 50 (11) ◽  
pp. 2289-2316 ◽  
Author(s):  
Peter G. Kevan

Some review, concepts, terminology, and methods are given towards the description of colors, here, of flowers of the high arctic flora of the Canadian Arctic Archipelago, in the insect (including ultraviolet) and human visual spectra. Photographs and spectral reflection curves are given. The various flower colors found elsewhere do not occur in the same proportions in the high arctic where white and yellow predominate. Ultraviolet is reflected from several yellow (insect-red) flowers, making them insect-purple. Patterns and markings in the ultraviolet or other colors may be simple or complex, but cannot be described as honey-guides. To insects, the high arctic flowers of the different species have more distinctive colors and color patterns, and there are more different colors and color patterns, than there are to humans. Most flowers have greater luminance factors than do their backgrounds so stand out as different in color and brightness. Yellow flowers (with or without ultraviolet) are the most attractive to insects; other colored flowers are visited by special groups of insects or when yellow flowers are not available, or both. Color alone cannot account for the attractiveness or unattractiveness of some blooms. Some flower visitors are found in flowers in which they would be least conspicuous, and cryptic color changes may operate in the high arctic crab spider.


2019 ◽  
Vol 13 (4) ◽  
pp. 358-374
Author(s):  
Mark B Salter

Abstract Canada's policies to assert and maintain sovereignty over the High Arctic illuminate both the analytical leverage and blind spots of Foucault's influential Security, Territory, Population (2007) schema for understanding modern governmentality. Governmental logics of security, sovereignty, and biopolitics are contemporaneous and concomitant. The Arctic case demonstrates clearly that the Canadian state messily uses whatever governmental tools are in its grasp to manage the Inuit and claim territorial sovereignty over the High North. But, the case of Canadian High Arctic policies also illustrates the limitations of Foucault's schema. First, the Security, Territory, Population framework has no theorization of the international. In this article I show the simultaneous implementation of Canadian security-, territorial-, and population-oriented policies over the High Arctic. Next, I present the international catalysts that prompt and condition these polices and their specifically settler-colonial tenor. Finally, in line with the Foucauldian imperative to support the “resurrection of subjugated knowledges” (Foucault 2003, 7), I conclude by offering some of the Inuit ways of resisting and reshaping these policies, proving how the Inuit shaped Canadian Arctic sovereignty as much as Canadian Arctic sovereignty policies shaped the Inuit.


2002 ◽  
Vol 54 (3) ◽  
pp. 301-315 ◽  
Author(s):  
Sandra Gordillo ◽  
Alec E. Aitken

Abstract This study examines neonto- logical and palaeontological data pertaining to arctic marine molluscs with the goal of reconstructing the palaeoecology of Late Quaternary ca. 12-1 ka BP glaciomarine environments in the Canadian Arctic Archipelago. A total of 26 taxa that represent 15 bivalves and 11 gastropods were recorded in shell collections recovered from Prince of Wales, Somerset, Devon, Axel Heiberg and Ellesmere islands. In spite of taphonomic bias, the observed fossil faunas bear strong similarities to modern benthic molluscan faunas inhabiting high latitude continental shelf environments, reflecting the high preservation potential of molluscan taxa in Quaternary marine sediments. The dominance of an arctic-boreal fauna represented by Hiatella arctica, Mya truncata and Astarte borealis is the product of natural ecological conditions in high arctic glaciomarine environments. Environmental factors controlling the distribution and species composition of the Late Quaternary molluscan assemblages from this region are discussed.


2001 ◽  
Vol 66 (3) ◽  
pp. 453-470 ◽  
Author(s):  
Peter C. Dawson

The semisubterranean whale-bone house is one of the most recognizable aspects of Thule Inuit culture. Following their arrival in the Canadian Arctic approximately 1,000 years ago, Thule peoples built these impressive and often enigmatic dwellings for occupation during the long winter months. Variability in the architectural properties of semisubterranean house forms has traditionally been used by archaeologists to infer cultural and historical relationships between regions, and establish seasonal and/or functional distinctions in usage. An analysis of 31 semisubterranean houses from two Thule winter village sites in the Canadian High Arctic using multivariate statistics and computer-aided drafting reveals a range of architectural variability that may represent attempts by Thule builders to accommodate 1) fluctuations in the availability of key building materials, 2) differences in household mobility, or 3) whaling-related social differentiation between households. These results have important implications for understanding the relationships among house form, environment, and culture in Thule Inuit society.


2013 ◽  
Vol 341 ◽  
pp. 68-85 ◽  
Author(s):  
Anna J. Pieńkowski ◽  
John H. England ◽  
Mark F.A. Furze ◽  
Steve Blasco ◽  
Peta J. Mudie ◽  
...  

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