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Freeze‐thaw cycles are most common at the beginning or near the end of the winter season. These cycles have various effects on the ecosystems of Eastern Canada, affecting both biotic and abiotic components of temperate cold environments. Using air temperature minima and maxima from four meteorological stations close to Québec City, we determined the frequency of daily freeze‐thaw cycles for the last 30 years. The results show no significant increase in the number of freeze‐thaw cycles despite a small increase in air temperature. Polynomial curves describing the relationship between mean air temperatures and the number of freeze‐thaw cycles were calculated. Based on these equations and anticipating a climate change scenario, we projected future freeze‐thaw cycles. Assuming a 5 °C increase in mean air temperatures by 2100, we estimated that the number of days with a freeze‐thaw cycle could increase by approximately 20 days per winter. The increase in the number of such cycles will be concentrated during the coldest months of the winter (January and February).  相似文献   

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This paper investigates the establishment of trading regions in the global economy at the national level using a measure of trade intensity and a regional assignment algorithm that generates economically meaningful trading regions. Although there is definite regionalization in the global economy with regard to international trade, there is no evidence of an increase in the concentration of that regionalization over time. The geography of international trade is incredibly dynamic, with change related to political, historical and economic forces. Overall, trading regions have relatively few members and are increasingly a set of geographically close countries.  相似文献   

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In universities, as in everyday life, there is a fundamental need for geographical knowledge, even when no formal departments exist to provide instruction. This need was true in the University of Toronto during the decades before Griffith Taylor was appointed in 1935 to the first university Chair in geography in English‐speaking Canada. Using matriculation and annual university course examinations, university calendars and the papers of President Falconer and Professors James Mavor and Harold Innis, I trace the development of geography at the University of Toronto from the mid‐nineteenth century to the arrival of Taylor. Courses taught in selected aspects of physical and human geography in the Departments of Geology, Political Economy and History are particularly significant. Underlying this instruction, and also the desire to establish a geography department, was an acute awareness of the fundamental importance of geography to help understand a large regionally complex homeland, and a wider world.  相似文献   

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Zoos and aquariums are responding to the worldwide biodiversity crisis through major conservation initiatives like captive breeding for assurance populations and reintroduction programs. These institutions also fundraise, offer education programs, and provide critical research on biodiversity. Through a case study inside three accredited Canadian zoos, this paper illustrates that zoos and their staff members are being incorporated into many official species‐at‐risk recovery efforts on provincial, federal, and international levels. Specifically, the zoos studied are involved in every stage of the recovery process, from providing valuable research and habitat analyses, to captive breeding animals for reintroduction, to writing recovery strategies and creating recovery policy for multiple jurisdictional levels. Zoo staff indicate that zoos are uniquely suited to conservation because zoos have space, expertise, apolitical status, and the ability to connect with the public. Overall, the paper suggests that zoos can significantly contribute to species‐at‐risk protection and recovery in Canada and beyond.  相似文献   

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The Province of Alberta in 2001 implemented the First Nations Gaming Policy (FNGP) to improve First Nations development potential by permitting the construction of reserve casinos. This article argues that during the policy development stages provincial and First Nations leaders failed to consider the geographic placement of reserve communities, both in terms of where casinos would be placed and how gaming revenues would ultimately be distributed. Therefore, a policy intended to assist with First Nations economic rejuvenation in Alberta has benefitted a small proportion of First Nations while exacerbating regional economic difficulties the policy was in part calculated to ameliorate. The authors recommend revisiting the FNGP to establish a more equitable revenue distribution formula, thus resulting in a greater distribution of gaming revenues to a larger number of First Nations.  相似文献   

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This article examines the location of functions within the electricity sector in Canada from 1971 to 2001, using a centre‐periphery model. Power generation, distribution and retailing are generally carried out by multiestablishment crown corporations. Location patterns of different functions—management, scientific, production, etc.—are analyzed via the use of occupational groups. The spatial distribution of functions is found to be generally consistent with centre‐periphery relationships, with evidence of a growing functional specialization between large metropolitan and nonmetropolitan locations. However, differences emerge depending on power generation sources: fossil fuels, hydro, nuclear, solar or biomass. The choice of a power generation source has consequences for local economies.  相似文献   

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We examine Canada's recent Syrian Refugee Resettlement Initiative (SRRI) paying close attention to the resettlement role played by mid‐sized urban communities. We elaborate on a key policy dimension at work at this scale of action: local immigration partnerships (LIPs). We start with a very brief review of Canada's history of mass refugee resettlement. Second, we assess the policy of LIPs, particularly how they have been presented as a form of “place‐based policy,” and third, we offer an overview of the role the LIPs played in three case study communities (Hamilton, Ottawa, and Waterloo) during the SRRI. Finally, we present three overarching themes that emerged from our research in each of these communities: the importance of each community's history of immigration and refugee resettlement; the embeddedness of the LIP and its leadership in the local community; and how the positioning of each LIP relative to the three levels of government and its official Resettlement Assistance Program agreement holders impacted its ability to act. The history, location, and place characteristics of each community influenced the nature of intersectoral and intergovernmental relations in distinctive ways, and differentially shaped the effectiveness of each LIP's ability to contribute to the SRRI.  相似文献   

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In 1833, the Commons chamber was described as a ‘noxious vapour‐bath’, while the Lords deemed the insufferable heat and toxic smoke in its House as injurious to health. This situation was not new, as for more than a century both Houses had been battling with officialdom and technology to improve their working conditions. In their continuing quest for effective heating and ventilation they had drawn in many respected men of science and commerce as well as entrepreneurs and showmen of varying abilities, to little avail. Many machines were tried, Desaguliers's ventilating wheel alone achieving modest success. A notable institution arising from all these experiments was the ventilator in the Commons’ roof, enabling ladies, barred from the chamber, to witness debates, albeit in considerable discomfort. After the 1834 fire, parliamentarians renewed their ventilating mission in their temporary chambers, before projecting their cumulative experience and opinions onto the far larger canvas of the new Victorian Palace of Westminster.  相似文献   

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In the context of global warming, changes in extreme weather and climate events are expected, particularly those associated with changes in temperature and precipitation regimes and those that will affect coastal areas. The main objectives of this study were to establish the number of extreme events that have occurred in northeastern New Brunswick, Canada in recent history, and to determine whether their occurrence has increased. By using archived regional newspapers and data from three meteorological stations in a national network, the frequency of extreme events in the study area was established for the time period 1950–2012. Of the 282 extreme weather events recorded in the newspaper archives, 70% were also identified in the meteorological time series analysis. The discrepancy might be explained by the synergistic effect of co‐occurring non‐extreme events, and increased vulnerability over time, resulting from more people and infrastructure being located in coastal hazard zones. The Mann Kendall and Pettitt statistical tests were used to identify trends and the presence of break points in the weather data time series. Results indicate a statistically significant increase in average temperatures and in the number of extreme events, such as extreme hot days, as well as an increase in total annual and extreme precipitation. A significant decrease in the number of frost‐free days and extreme cold days was also found, in addition to a decline in the number of dry days.  相似文献   

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This palaeodietary study presents carbon and nitrogen stable isotope data from human and faunal skeletal remains from the Copper Age settlement of Valencina de la Concepción–Castilleja de Guzmán, located in Seville, Spain. Montelirio, the only Valencina–Castilleja human group from which we have obtained reliable palaeodietary results, had a diet based on C3 terrestrial resources, including both plants and animals. The protein component of the diet consisted mainly of meat, milk and dairy products from livestock as well as C3 plant protein from cereals and pulses. This study compares data from Montelirio, the Copper Age group from Valencina–Castilleja, with the published data from other Iberian Late Neolithic–Copper Age (LN‐CA) societies. This comparison reveals a homogeneous diet with some exceptions. Overall, the LN‐CA diet in the Iberian Peninsula consisted mainly of animal proteins from meat, milk and dairy products from livestock as well as C3 plant sources from the characteristic agriculture of the societies of these periods. This study also demonstrates the minor use of aquatic resources from the Neolithic to the Copper Age period in the Iberian Peninsula. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

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Following the rapid demise of local coalmining in the 1950s and early 1960s, the former coal towns of the Cessnock area have survived in their newfound dormitory role, with cheap serviced housing acting as a major constraint on out–migration and an incentive for in–migration for low–income householders, mainly engaged in external commuting or outside the workforce. Behavioural responses to widening local job deficits in the early 1960s were reported in this journal (Holmes, 1965). From household surveys and other sources, Holmes examined the interplay between individual, household and locality variables and presented a spectrum of projected future outcomes for localities, according to accessibility, size and service provision, either attached to the Newcastle–Maitland labour market as low–income outer suburbs or experiencing varying rates of decline while providing low–cost welfare housing. While these broad trends have continued over the last 35 years, significant variants, not predictable in 1965 have emerged, notably: the increased residential attractiveness of some small localities; the strengthening of welfare migration, notably from Sydney; the increase in non–workforce households; and, some evidence of emerging socio–economic polarisation in larger towns. In these respects, Cessnock localities can be viewed as a microcosm of wider trends in Australian society, trends which are most fully revealed in disadvantaged metropolitan peripheral localities.  相似文献   

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