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ABSTRACT. The I.G.U. Commission on Periglacial Morphology was set up in 1949 and Us first report was presented to the 11th Congress in Washington in 1952. Between 1952 and 1956, the Commission published a select bibliography on periglacial phenomena and a few national maps were produced. A short study on Canadian periglacial morphology appears in the general report to the 16th Congress in Rio de Janeiro in 1956. From that date Canada has been represented on the Commission, which has met in Spain and Poland. During 1959, a national map of Canadian periglacial phenomena will be prepared for presentation at the 19th Congress in Stockholm in 1960.  相似文献   
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Cet article vise à préciser la position possibiliste de Harold Innis, a G en explorer les fondements et à en dégager la portée dans son oeuvre. On montre que les orientations de base de son possibilisme sont très convergentes avec celles des vidaliens. Ses points d'appui néo-kantiens sont soulignés à ce sujet. Sa portée est manifeste dans trois thèmes: la problématique de la formation territoriale du Canada, I'importance de la technologie et la part accordée à la liberté humaine .
This article aims at outlining the possibilist position of Harold Innis, at exploring its foundations, and at showing its bearing on his written work. It is shown that the basic orientations of his possibilism converge with those of the Vidalians. In this respect, its neo-Kantian supports are underlined. Its significance in his thought is made apparent in three themes: the problem of, and approach to, the territorial formation of Canada, the importance given to technology, and the leeway given to human free will .  相似文献   
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Indigenous methodologies are an alternative way of thinking about research processes. Although these methodologies vary according to the ways in which different Indigenous communities express their own unique knowledge systems, they do have common traits. This article argues that research on Indigenous issues should be carried out in a manner which is respectful and ethically sound from an Indigenous perspective. This naturally challenges Western research paradigms, yet it also affords opportunities to contribute to the body of knowledge about Indigenous peoples. It is further argued that providing a mechanism for Indigenous peoples to participate in and direct these research agendas ensures that their communal needs are met, and that geographers then learn how to build ethical research relationships with them. Indigenous methodologies do not privilege Indigenous researchers because of their Indigeneity, since there are many ‘insider’ views, and these are thus suitable for both Indigenous and non‐Indigenous researchers. However, there is a difference between research done within an Indigenous context using Western methodologies and research done using Indigenous methodologies which integrates Indigenous voices. This paper will discuss those differences while presenting a historical context of research on Indigenous peoples, providing further insights into what Indigenous methodologies entail, and proposing ways in which the academy can create space for this discourse.  相似文献   
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Vegetation stress or mortality can be the result of many factors including drought‐induced water deficit, insect infestations and failures of, or fluctuations in, precipitation sources typical to an area. Reduction of cover and reduced health are identifiable in remotely‐sensed multispectral satellite images. A suite of images from NASA's MODIS sensor was used to calculate the Normalised Difference Vegetation Index (NDVI) during the 2000–2006 North American growing seasons. Fluctuations in NDVI over this period show a significant decline in vegetative health in the region with specific areas showing changes linked to moisture sources, prevailing wind patterns, slope aspect and solar radiation receipt. Ground‐truthing of these areas has confirmed the extent and magnitude of the dieoff signal. Historically, dieoff has been reversed through regeneration as climate conditions return to a normal regime. However, quantification of recent vegetative change in western North America suggests that the degree of change may be too severe for regrowth to occur and may have far‐reaching impacts on a scale unseen in modern times. The loss of vegetative habitat and native species in semi‐arid regions and lack of regeneration in these marginal ecosystems due to prolonged drought are growing global problems. Similar drought stress impacts on marginal ecotypes have also been observed in semi‐arid regions of Australia, South America, Asia and Africa. Observations of the spatial pattern of temperate forest vegetation globally can be used to develop a precise picture of vegetative health in these regions and how they are reacting to global climate change.  相似文献   
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