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As features of the landscape, waterfalls have been studied extensively by geographers, but the names given to these landforms have received relatively little scholarly attention. This paper examines the naming of waterfalls and addresses the question of classifying these hydronyms. The subject is considered in a global historical context, focusing on place names in the anglophone world. Until the 18th and 19th centuries, relatively few waterfalls were named. With the beginning of the Industrial Revolution, water power rose in economic importance, and at the same time, there was a growing scientific and aesthetic engagement with the landscape. These developments are suggested as reasons for the increased interest in waterfalls which were then being recorded in topographical literature and on maps, individual names being given to increasing numbers of falls. European exploration added to the knowledge of the world's waterfalls, many of which were given names by their ‘discoverers’. This naming process accelerated with the growth of domestic and overseas tourism which exploited scenic resources such as waterfalls. Until now, research on the names of waterfalls has been fragmentary, and the classification of these hydronyms has been neglected. This paper demonstrates that waterfall names can be classified in accordance with a recognised toponymic typology. Using examples drawn from waterfall guidebooks, databases, maps, and other sources, the following discussion supports George Stewart's claim that his toponymic classification is valid for place names of all kinds.  相似文献   
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Intermodal freight terminals: locality and industrial linkages   总被引:2,自引:0,他引:2  
The areas around eight Canadian intermodal freight terminals form the focus of this study. Two basic research questions are addressed: What is the character of the zones adjacent to the terminals and what is the functional tie between industries located in these zones and the terminals themselves? There are three seaports (Halifax, Montreal and Vancouver), three airports (Dorval‐Montreal, Pearson‐Toronto and Vancouver) and two rail yards (both in the Toronto region) in the study. In total, 196 manufacturing and wholesaling firms were part of the study. Transportation land use is areally most extensive in six of the eight terminal zones. Industrial land use, while significant in area, is not the most dominant land use surrounding any of the terminals. No one socio‐economic characteristic defines the areas around the terminals. Businesses in close proximity to the terminals make rather modest use of the terminals. Less the 30 percent of the interviewed firms used the nearby terminal for their freight shipments; only 3 percent of the firms indicated that proximity to the terminal was a primary locational consideration. The relationship between industrial location and the terminals is more indirect, than direct, based on the high level of accessibility found in the terminal zones.  相似文献   
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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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Whither (or Wither?) Geography   总被引:1,自引:0,他引:1       下载免费PDF全文
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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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