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BRIAN KLINKENBERG 《The Canadian geographer》2001,45(3):414-426
Using a compiled list of the vascular flora for 21 islands in the western basin of Lake Erie, Preston's resemblance measure and Connor and Simberlof's Null Hypothesis I were applied to native and alien species subsets in order to examine how these findings fit within the equilibrium theory. Based on Preston's measure, it was found that the similarity of species between island pairs was more likely to fit with MacArthur and Wilson's equilibrium theory when native species were considered than when alien species were considered. Native species have restricted distributions - especially those found on the smaller islands - and appear to be less randomly distributed about the islands. This study also found that a large component of the alien flora is widespread in its distribution, and appears to be randomly distributed among most of the islands. 相似文献
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BRIAN FINLAYSON 《Geographical Research》2015,53(2):119-120
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LANDSCAPE AND CLIMATE CHANGE IN THE CENTRAL CANADIAN ROCKIES DURING THE 20TH CENTURY 总被引:2,自引:0,他引:2
BRIAN H. LUCKMAN 《The Canadian geographer》1998,42(4):319-336
This paper reviews selected evidence of environmental changes in the central Canadian Rockies during the 20th century. The instrumental climate record shows that mean annual temperatures have risen ca. 1.4°C over the last 100 years but seasonal patterns of change are complex. The greatest increases have been in winter temperatures (3.2°C / century). Precipitation data, though limited, show variable patterns of change on decadal scales with generally higher levels of precipitation in the mid-20th century. The longest streamflow record also shows considerable variability, with highest flows in the 1950s. A tree-ring-based temperature reconstruction indicates summer and spring temperatures in the last half of the 20th century are higher than any equivalent period over the last 900 years. Although no accurate regional estimates exist, glaciers have probably lost ca. 25% of their area in the last 100 years and may be smaller now than they have been at any time in the last 3000 years. These two lines of evidence suggest that the climate of the late 20th century is exceptional in the context of the last 1000 to 3000 years. Small but significant vegetation changes are taking place at the upper treeline ecotone in response to climate changes over the 20th century (e.g., seedling establishment). However, the most significant landscape change in the last 100 years is the transformation of the character of the montane forest due to a reduction in forest fire frequency, largely due to an active policy of fire suppression. Dans cet article, on révise certaines manifestations des changements environnementaux qui se sont produits dans les Rocheuses canadiennes au cours du 20ème siècle. Ce registre instrumental climatologique indique que les moyennes annuelles de température ont augmenté d'environ 1,4°C en 100 ans, mais les modèles de changements saisonniers sont complexes. Les plus fortes augmentations ont été notées dans les températures hivernales (3,2°C/siècle). Les données concernant les précipitations - bien que limitées - indiquent des tendances variables de changement selon les décennies et en général des niveaux plus élevés de précipitation au milieu du 20éme siècle. Le plus long enregistrement des débits d'un cours d'eau indique aussi d'importantes variations, les débits les plus forts se situant dans les années 1950. La reconstruction des relevés des températures faite à partir des cernes montre que les températures estivales et printanières de la deuxième moitié du 20ème siècle sont plus élevées qu'elles ne l'étaient durant les périodes correspondantes des 900 dernières annés. Même s'il n'existe aucune donnée règionale exacte, les glaciers ont probablement perdu à peu près 25% de leur superficie au cours du dernier siècle et ils ont atteint leur plus petite taille des 3000 dernières années. Ces deux preuves suggèrent que le climat de la fin du 20ème siècle est exceptionnel dans le contexte des 1000 à 3000 dernières années. Des changements mineurs mais significatifs s'effectuent actuellement dans l'écotone supérieur de la limite des arbres à cause des changements climatiques du 20ème siècle (ex. l'implantation de nouvelles pousses). Pourtant, pendant le dernier siècle, la transformation la plus significative s'est effectuée dans les forêts de montagne. Grâce à une politique active de suppression des incendies de forêt, ceux-ci sont beaucoup moins fréquents. 相似文献
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BRIAN DICKEY 《The Journal of religious history》1991,16(3):349-353
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Since the earliest days of the European Enlightenment, Western people have sought to remove themselves from nature and the ‘savage’ non‐European masses. This distancing has relied upon various intellectual techniques and theories. The social construction of nature precipitated by Enlightenment thinking separated culture from nature, culture being defined as civilised European society. This separation has served to displace the Native voice within the colonial construction of Nature. This separation has also served as one thread in the long modern ‘disenchantment’ of Westerners and nature, a ‘disenchantment’ described so adeptly by Adorno and Horkheimer (1973 ). Unfortunately though, this displacement is not only a historical event. The absence of modern Native voices within discussions of nature perpetuates the colonial displacement which blossomed following the Enlightenment. In his book entitled, Native Science, Gregory Cajete describes Native science as ‘a lived and creative relationship with the natural world ... [an] intimate and creative participation [which] heightens awareness of the subtle qualities of a place’ (2000, 20). Perhaps place offers a ‘common ground’ between Western and Indigenous thought; a ‘common ground’ upon which to re/write the meta‐narrative of Enlightenment thought. This paper will seek to aid in the re/placement of modern Native voices within constructions of nature and seek to begin healing the disenchantment caused through the rupture between culture and nature in Western science. 相似文献
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BRIAN PORTER 《International affairs》2007,83(4):783-789
The different responses in Great Britain and the United States to Martin Wight as a thinker of international relations reveal something about the contrasting academic cultures of the two countries. Wight was pre‐eminently an ‘arts’ man, regarding history and philosophy as essential prerequisites for understanding the world. Above all he was concerned with the moral dimension in politics, whether domestic or international. His pacifism in the Second World War, curiously linked to his profound sense of realism, reflected deep religious convictions; indeed theology, and particularly eschatology, underlay much of his thinking. His career centres upon first Chatham House and Nuffield College, Oxford, then the London School of Economics and Political Science, and finally the University of Sussex. His lectures at the LSE on international theory achieved legendary fame, but he did not publish much in his lifetime. The appearance since 1977 of four notable posthumous works has enhanced his already high reputation, as has the increasing scholarly interest in the ‘English School’, of which he is now seen as a founding father. Ian Hall's book is a brilliant piece of analysis in which Wight's theological world view—which was not obtrusive in his teaching and writing—is investigated with a sureness that is probably rare among scholars in the international relations field. 相似文献