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John E. Martin 《The Canadian geographer》2011,55(4):457-469
Wetlands are common in Coastal Western Hemlock forests yet the hydrologic processes that generate runoff from small swamps are not completely understood. Direct field observations, hydrologic, and electrical conductivity data were collected from a gently sloping forested swamp complex from July to November 2009. Swamps occupied depressions between raised mounds (0.1 to 3 m high) and were connected by an ephemeral creek. Runoff was controlled by antecedent moisture conditions and influenced by basin microtopography. Two hydrologic regimes occurred during the study period and different runoff processes dominated each regime. Runoff was generated by subsurface flow during dry antecedent conditions as swamps remained hydrologically disconnected from each other. Runoff was generated by surface outflow from hydrologically connected swamps during wet antecedent conditions as ponded water spilled out of the depressions. The forested swamp complex produced a faster but limited hydrologic response during dry antecedent conditions compared to a slower but greater hydrologic response during wet antecedent conditions. Stormwater runoff and runoff ratios were up to two orders of magnitude higher in wet conditions than during similarly sized events in dry conditions. These factors should be considered when designing monitoring programs or runoff models in forested swamps with significant microtopography. Field surveys and estimates of hydrologic inputs and outputs may be useful in predicting the potential hydrologic connectivity of isolated forested swamps. 相似文献
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Laetitia Rouvire 《The Canadian geographer》2019,63(1):57-68
Based on the case of the Mohawk territory of Akwesasne, wedged between Ontario, Quebec, and New York state, this paper provides an analysis of the links between the affirmation of indigenous culture and the implementation of security policies on borderlands. The focus extends beyond political conflicts over border issues to encompass the ways in which Aboriginal sovereignty is affirmed within processes of negotiation and cooperation in the matters of identification requirements, border agents’ cultural sensitivity, and law enforcement. We find that the enhancement of border security can paradoxically be a political opportunity for local leaders to reaffirm indigenous sovereignty, and that this reaffirmation through cooperation is, at the same time, emerging as a key factor in the implementation of border security policies. 相似文献
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Mary Finley‐Brook 《The Canadian geographer》2011,55(3):334-353
The Canadian government and the Meadow Lake Tribal Council sponsored a forest extraction corporation in eastern Nicaragua that restructured 16 Miskitu and Mayangna villages and transformed local human‐environment interactions. The Central American aid project demonstrated paternalistic and interventionist tendencies and exposed biases in inter‐Indigenous aid that rendered it inseparable from conventional aid. This case encourages reflection on social and ecological impacts from the marketing of collective resources, the creation of Indigenous development corporations, and the decision‐making criteria and processes driving foreign aid. The case study demonstrates how foreign aid programs targeting Indigenous Peoples may actually thwart the self‐determination that they set out to encourage. Aid agencies and business partners, who had limited knowledge of local cultures and institutions, created externally defined rules that instigated resource conflicts and undermined the authority of customary leaders without resolving poverty or uneven development. 相似文献
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Randy W. Dirszowsky Sarah A. Finkelstein Anthony M. Davis 《The Canadian geographer》2013,57(2):173-185
Numerous anthropogenic stressors have impacted the region surrounding Sudbury, Ontario, leading to pronounced vegetation and landscape change. Few long‐term records exist to understand the nature or timing of this change. We use pollen analysis from radiometrically dated sediments of Clearwater Lake to compare pre‐ and post‐settlement vegetation. Beginning ～1850 CE, the record shows major shifts in forest composition, coincident with settlement and the beginnings of lumbering. These changes are unprecedented for the past ～5000 years, and consist of increases in diversity and abundance of deciduous tree taxa and herbaceous disturbance indicators. While evidence of mining appears as early as 1900 CE, little effect is seen in the pollen record until ～1930 CE, when sedimentation rates increased and acidification of the lake also began. At this time, further increases in palynological disturbance indicators and minimum sediment organic matter levels indicate the period of maximum vegetation loss. As a result of reduced emissions since the 1970s, water quality began to improve in Clearwater Lake and there are some decreases in the abundances of shade‐intolerant disturbance indicators in the pollen record. However, the fact that the pollen assemblages do not resemble those prior to 1850 suggests lasting vegetation changes. 相似文献
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An illustrated methodology for the morphodynamic sectoring of the Neigette River (Québec) Fluvial hydrogeomorphology is little recognized in policy management and planning in Québec. A better understanding would result in more enlightened planning for waterways. The deficiency could result from the fact that too few methodologies have been developed that take account of the particular nature of Québec rivers. This study tests the applicability of a methodology of dividing rivers into homogeneous morphodynamic units. This compartmentalization results from the analysis of longitudinal changes in stream power, sedimentary composition of the banks, channel entrenchment, and planform geometry. The method is tested on a section of the Neigette River, which encompasses a wide variety of forms and processes frequently found in Québec rivers. Results suggest the presence of three morphodynamic sections: wandering with multiple channels, dynamic meandering and stable meandering. The method provides an effective basis for discriminating between these morphodynamic environments and their respective limits. Stream power is the variable with the greatest discriminating capacity. The efficacy of the approach, the ease of its application, and its flexibility make this a valuable tool for the management of fluvial environments. 相似文献
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DEAN CARSON 《The Canadian geographer》2011,55(2):226-242
The Canadian ‘staples thesis’ literature has documented both the risks (in the tradition of Harold Innis) and the opportunities (in the tradition of W. A. Macintosh) inherent in economies that are dependent on the export of minimally processed natural resources. The key risk is that of retarded long‐term growth as a result of a lack of diversification and over‐dependence on foreign capital and markets. This article argues that the demographic consequences of staples approaches to development also make it difficult to achieve diversification. It profiles Australia's Northern Territory as an example of a mining‐dependent (fiscal) economy that demonstrates a particular demographic profile consistent with what might be expected of a resource frontier. The article argues, however, that restrictive demographic characteristics persist (high sex ratios, high population mobility, disadvantaged position of indigenous people and remote dwellers) even though mining has become an insignificant direct employer (less than one percent of the workforce) and the services sector drives the labour market. This persistence can be linked to the Territory and federal government expectations of economic development patterns in the region and the frontier mythology created around the Northern Territory. Addressing the demographic imbalance is a critical step towards realizing ambitions for economic diversification. 相似文献
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Rates of type 2 diabetes and other metabolic disorders are elevated among Indigenous peoples; however, no research has examined the origins of these diseases among the Métis. This case study documents a transition in lifestyle and health that affected the Keg River Métis of northern Alberta during the middle decades of the 20th century. This community began to experience previously absent diseases, including obesity, heart disease, gestational and type 2 diabetes, and preeclampsia. This shift in disease burden appears tied to rapid socio‐cultural and economic change driven by a decline of traditional economic activities, access to government transfer payments and wage labour, an increasingly sedentary lifestyle, and a growing availability of non‐traditional foods. This study points to earlier emergence of diabetes among Canadian Indigenous populations than commonly credited and presents the case for a rapidly evolving epidemic tied to environmental and cultural change. Underlying this were structural changes that emerged out of colonization. 相似文献
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Parks Canada began the Northern Satellite Monitoring Program in 1997, with the objective of tracking large‐scale vegetation variation in Canadian ecosystems and helping land managers to develop appropriate management practices in response to climate change. Under this program, a sequence of 10‐day composite Advanced Very High Resolution Radiometer (AVHRR)‐derived Normalized Difference Vegetation Index (NDVI) data from 1985 to 2007 was examined to study seasonal and inter‐annual relationships between vegetation and climate data over Canadian ecosystems using statistical and wavelet analysis. Statistical analysis showed that temperature was the principal driver for seasonal variability in greenness, explaining more than 70 percent of seasonal variation in vegetation for most Canadian ecozones. In comparison with temperature, the relationships between NDVI and precipitation were weaker but still significant. Maximum annual NDVI showed increasing trends in Canadian ecozones during the study period, although increasing rates were spatially heterogeneous. Wavelet analysis confirmed that inter‐annual variation in NDVI was different at two ecozones in Canada. NDVI variation in the Northern Arctic was significant at scales of 3–4 years from 1997 to 2001, which was associated with temperature and precipitation variation. Comparatively, NDVI variation in the Boreal Shield was significant at scales of 5–8 years from 1991 to 1999, but did not correspond with climate variation. 相似文献
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Geographers working in mountainous northern Pakistan note that gains in accessibility following the Karakoram Highway's official opening in 1978 significantly reshaped social organization, economic activity, and land use across the region. These valuable regional‐scale analyses provide few insights regarding the contingent and variable ways new roads are conceived and experienced at the community and household level by the people whose mobility they drastically impact. This article addresses that limitation of regional research by focusing on an individual agricultural community called Shimshal that in 2003 completed a 40‐kilometre link‐road connecting it to the highway. Drawing from qualitative information gathered before and after the Shimshal road's completion, we briefly describe the community's motivation for constructing the road, villagers’ accessibility‐related hopes and concerns as it was being built, and some of the social, cultural, and economic changes that followed the road's completion. The article concludes by summarizing the community's response so far to landslide‐induced destruction of over 20 kilometres of the Karakoram Highway which, since January 2010, has left community members without vehicular access to the rest of Pakistan just seven years after their link‐road's completion. 相似文献
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G. Mauran L. Bassel C. Ferrier D. Lacanette B. Bousquet R. Chapoulie 《Archaeometry》2019,61(2):327-341
Cave Art is a fragile testimony of past human societies and the development of modern behaviours. In limestone caves, moonmilk commonly endanger the artworks. It is a calcite deposit with a large variability of chemical composition and morphological structures and it hosts numerous microbial communities. The possibility to characterize this deposit in the field would aid in a better understanding of cave behaviour and allow the setting up of proper conservation measures. The present study analyses the variability of a moonmilk strip of metric size in Leye Cave in the Vézère Valley (Dordogne, France). The cave was not ornate and was selected as a laboratory cave in which in‐situ observations and micro‐sampling could be carried out, before they were performed in cavities hosting parietal artworks. Scanning electron microscope (SEM) observations of 24 samples allowed, for the first time, an investigation of the variability of moonmilk deposits over the same wall of a few metres dimension. The observations highlighted the low variability of the moonmilk at the microscopic scale when regarding the chemical composition and morphological structures, despite significant macroscopic diversity, thus providing insights into how to optimize the sampling strategy of moonmilk in ornate caves. 相似文献
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Starting from an econometric model of local employment growth, applied to Canada (1971–2001), residuals—relative to model predictions—are analyzed over time and over space, in turn allowing us to draw a distinction between general explanatory variables and factors of a more local, cyclical or accidental nature. The model's explanatory power grows over time, founded on variables such as urban size, market access and industrial structure, allowing us to conclude that local employment growth in Canada follows an increasingly geographically predictable pattern. However, an examination of the residuals reveals more localized processes. Growth volatility is most manifest in Alberta and British Columbia, home to the most erratic local economies. Emerging patterns are visible in the last period, most notably the underperformance of Northern Ontario and of non‐metropolitan communities between Windsor and Québec City, lying along the Great Lakes and the Saint Lawrence. The over‐performance—compared to model predictions — of small and mid‐sized towns in south‐eastern Québec can, on the other hand, be interpreted as a sign of truly local social processes, generally associated with a particularly dynamic local entrepreneurial class. 相似文献
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Scientists advise limiting global warming to 1.5°C with substantial actions by 2030. Our viewpoint argues that climate response strategies in Canada have underemphasized and underestimated the potential contribution deep energy retrofits can make to greenhouse gas (GHG) emissions reductions, leading to inadequate responses in the building sector, and that Canada can (and should) be ambitious with building retrofits over the next decade. GHG savings from building retrofits can be realized more quickly than GHG reductions from other sectors, and either deliver net cost savings or are cost‐effective when compared to other mitigation measures. Retrofits can also provide social and economic benefits, such as improved health and comfort, and lower energy costs. This paper reviews energy use and building retrofits in Canada and argues the following should be implemented: (1) focus innovation on deep energy retrofit processes, not singular retrofit actions; (2) maximize both social and environmental benefits; (3) improve data gathering and availability for analysis and delivery; (4) innovate for a process of decisions and to avoid “dropouts” during the retrofit process; and (5) focus innovation on business models that maximize benefits. 相似文献