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1.
Chris Banister  Nick Gallent 《Area》1998,30(4):331-341
Summary It is widely accepted that the nature and extent of commuting patterns worldwide represent a large slice of the overall environmental problems associated with transport use. There has been a long-standing concern over the 'congestion peaks' derived from daily travel-to-work patterns, and a preoccupation with the ways in which greener modes of commuting might contribute to a more environmentally benign transport system. This article uses Census data to focus on commuting patterns in England and Wales, concluding that, despite recent moves towards promoting a more integrated and sustainable transport system, worrying trends persist that would seem to undermine this strategy. On a more positive note, the Census data also suggest that many shorter trips might potentially be converted to 'greener modes' walking or cycling–with substantial environmental benefits.  相似文献   

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Episodic high rainfall has been proposed as an important factor in perennial species recruitment but flooding based on rainfall at a distance from the site has received little attention. Although such flood events in arid Australia are rare, studies of the ephemeral Olary Creek indicate that occasional floods can also have a high impact on the vegetation and landscape. During February 1997, a high-rainfall event caused flooding in the Olary Creek. One branch of the creek created a terminal lake within mallee vegetation on Nagaela Station in far-western New South Wales. The flood path of Olary Creek and this terminal lake allow study of the importance of rainfall-driven flood events in shaping vegetation in arid environments. This paper reports (i) the response of arid land plant species to high-rainfall-driven episodic flood events and (ii) how grazing pressure from native and introduced herbivores can impact on native species response.

A systematic study was conducted to understand the botanical composition in flooded and control areas based on 25 m2 fenced and unfenced plots subjected to flooding and non-flooding. For 6 years following flooding, species richness in the flooded area was twice that of unflooded areas. In particular, 27 native species from 13 families were recorded both in the enclosed and open plots located in the flooded area. Over the study period nine species: Brachyscome ciliaris, Helichrysum leucopsidium, Vittadinia cuneata, Casuarina pauper, Maireana sedifolia, Salsola kali, Sclerolaena obliquicuspis, Eremophila sturtii and Eucalyptus foecunda germinated only in the flooded enclosed plots. Further, 11 exotic species from five families were recorded in the flooded (both enclosed and open) plots over the study period. Knowledge gained from this study will contribute to management strategies for arid land vegetation.  相似文献   


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There is a sizable literature about the factors shaping park visitation and use – especially for urban parks, including (i) geographic (e.g. proximity), (ii) socio-cultural (e.g. population characteristics) and to a lesser extent, (iii) individual psychometric factors (e.g. attitudes and values). Yet comparatively little is known about how factors related to distance may affect peri-urban national park use, particularly outside the United States. This paper reports on research investigating distance-related factors affecting use of a peri-urban national park in Brisbane, Australia. This study found that older visitors live closer to the park while younger visitors travel further to use it. Surprisingly, travel distance did not vary with the type of recreational activities that users were conducting in the park. These results have implications for park planning and management including user demand for different recreational activities in peri-urban national parks. Results are useful for scholars using distance decay models to explain travel behaviour, evidencing the empirical veracity of the model in different places and across different service types. The findings are especially important for geographers because they demonstrate that assumptions about uniform park catchments may be unsupported and need to be empirically validated.  相似文献   

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Rural areas in developed economies are becoming increasingly multi-functional in that their character is being shaped by a mix of production, consumption and conservation values. Agriculture may remain the dominant land use, but many landholders do not see themselves as farmers by occupation. Researchers have demonstrated that occupational identity influences land use and management. However, efforts to explore the influence of occupational identity often rely on surrogate measures and have largely ignored identity theory. We build on research demonstrating that collective identity theory can be used to develop a valid and reliable measure of farmer identity and to then classify rural landholders across a natural resource management (NRM) region. The contribution of this paper is to explain how that measure of farmer identity can be mapped and then demonstrate the relevance of doing so for regional NRM in Australia. As expected, farmer identity varied across the case study region with distance from urban centres, and across different environmental assets. Those findings should lead to a more targeted approach to landholder engagement in NRM. We suggest that farmer identity (i.e. farmer-collective occupational identity construct; F-COIC) might provide a next step for responding to the challenges of interpreting and mapping multi-functionality.  相似文献   

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This study examines the spatiality of interlocking directorates of Canadian companies, with particular emphasis given to international interlocks. From a geographical standpoint, do these connections to foreign firms reinforce the importance of Canada’s top corporate cities as ‘gateways’ to international business? Is there a geography associated with the interlocking to these gateway cities? Findings build on James O. Wheeler’s body of research focused on corporate headquarters. This study is placed within the context of the current economic geography dialogue. Particular focus is placed on Saxenian’s theory of brain circulation, wherein she argues that individuals with international experience serve as brokers linking domestic businesses with those in distant regions. A further purpose of this study then is to examine Saxenian’s argument in the context of Canadian corporations. First, is there a geographical association between directors’ foreign educations and where Canadian firms are interlocked to internationally? Second, the corporate performance of Canadian firms interlocked internationally will be measured against those firms that are not. It seems logical to assume that increased connections would yield more diverse and rich knowledge, which could lead to better decisions, and thus corporate performance, in today’s global world. But does it? This study finds that being linked to an international company through a common director did translate into more profitability for Canadian firms. Findings also revealed a geographical link between international interlocks and a director’s foreign education. However, when Canadian firms were interlocked with an international company with a director who had international education, greater profits did not necessarily result.  相似文献   

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Niantic Labs has developed an augmented virtual reality mobile app game called Ingress in which agents must seek out and control locations for their designated factions. The app uses the Google Maps interface along with GPS to enhance a geocaching-like experience with elements of other classical games such as capture-the-flag. This study aims to assess the effect Ingress can have on introductory to physical geography students. These goals include: whether the students can acquire greater geographical interest through Ingress, garner a sense of community, and whether students exhibit improved exam scores in the classroom.  相似文献   

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As medical geography reinvents itself as health geography, the linkages between social theory and the deconstruction of central categories organizing its medical orientation are being explored. This paper discusses the contribution of qualitative research to this process. In providing access to alternative ways of understanding health concerns, and emphasizing issues of power in the production of knowledge, qualitative methodology carries the potential for reconceptualizing key issues framing investigation of the relationships between place, people, and their health. In pursuing current issues in social theory, qualitative research also contributes to the blurring of the subdiscipline's boundaries and revitalizes its agenda.  相似文献   

9.
Seasonal stratospheric ozone depletion in the Arctic has raised the question of whether the associated increases in ultraviolet-B (290-320 nm) constitute a significant health risk in Arctic populations. Increases in skin cancer in Europe and the USA from excess UV-B resulting from ozone depletion have been predicted. Skin cancer is, however, rare in Inuit populations.
UV-B also causes a selective down regulation of the immune system which may be a natural regulatory mechanism evolved to prevent autoimmune attack on sunlight-altered skin. The action spectrum for UV-B immunosuppression implicated a unique skin photoreceptor molecule, urocanic acid (UCA), which isomerizes from the trans to the cis isomer on exposure to UV-B, the cis isomer being immunosuppressive. This form of immunosuppression is important in skin cancer and possibly in infectious diseases.
The epidemiology of non-Hodgkin's lymphoma shows a relationship with UV exposure, postulated to be via the immunosuppressive effects of UV-B. Cancers which show an excess in Inuit populations include nasopharyngeal and salivary gland cancer. Genetic factors appear to be involved, but these are thought to be virally related cancers possibly associated with the high viral load in these populations. In several studies on non-Arctic populations, salivary gland cancer has been linked to ultraviolet exposure. A potential role for UV-B exposure in these cancers in the Arctic needs to be explored.
In view of the high levels of POPS in some Arctic regions, potential interactions between the immunosuppression caused by some of these pollutants and the effects of UV-B need to be investigated.  相似文献   

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《Urban geography》2013,34(8):898-926
Manufacturing establishments are integral to the spatial structure of fast-growing Sunbelt metropolitan areas, but most concepts and theories of intrametropolitan location were largely developed for an earlier technological era and different spatial contexts. This article investigates the location of nine disaggregated manufacturing sectors in Phoenix, Arizona, showing varying degrees of central core concentration and metropolitan-wide clustering. Distinct sectoral co-location patterns are also evident. We interpret our results as evidence that the intrametropolitan location of postindustrial manufacturing is best understood as a series of spatial distributions with varying concentration, centralization, clustering, and other order-based characteristics. There is little evidence that randomly scattered discrete industrial zones have developed nor that spatial patterns are uniform. Enduring lock-in effects tied to transportation infrastructure are pivotal to understanding the locational distribution of manufacturing industries in metropolitan Phoenix. Results do not support a hypothesis that a positive relationship exists between establishment size and distance from sectoral mean centers.  相似文献   

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Relationships between landscape-scale geomorphology and aspects of the human environment (including heritage and material cultures) are best examined in landscapes with a strong geomorphological imprint of past climatic and environmental changes, and where human activity has been present for a long period of time. In Cornwall, southwest England, a strong geomorphological signature is imparted by weathering of granite bedrock under cold Quaternary climates, and a strong cultural and heritage imprint is manifested in material and nonmaterial ways through archaeology, art, literature and folklore, and is illustrated in this paper through examples of Bodmin Moor (north Cornwall) and West Penwith (west Cornwall). Landscapes of Bodmin Moor include wide valleys with underfit rivers and upland summits with prominent tors, resulting from granite weathering and slope processes during the Tertiary and Quaternary. Pollen records show how human activity has changed on the moor over time, with a peak of settlement during the Bronze Age, and expansion of grazing into the Iron Age. Daphne du Maurier's novels, set on or adjacent to Bodmin Moor, emphasize the moor's relationship to unstable and intense human emotions and crises. In West Penwith, which is geomorphological similar to Bodmin Moor, geomorphology–culture relations are demonstrated in different ways but through a similar sense of place and regional identity. The St Ives School of early 20th Century art, including the local artist Peter Lanyon and the sculptor Barbara Hepworth, draws inspiration from the local land and seascapes. The oral traditions and folklore of Zennor emphasize the importance of witchcraft and superstition that are in part founded on the wildness of upland summits and stormy coastline. Across West Penwith, tin mining and the mining trade exerted a strong impact on regional socioeconomic and cultural development from the Bronze Age until the end of the 19th Century, seen through settlement patterns, scientific innovation and Nonconformism. Today these geomorphology–culture relations are memorialized in the Cornwall and West Devon Mining Landscape World Heritage Site.  相似文献   

13.
LI Yuechen 《地理学报》2008,18(1):85-94
The 13 provinces (autonomous regions and municipalities) in northern China are located in latitude 31°–54°N and longitude 73°–136°E including Beijing, Tianjin, Hebei, Shanxi, Inner Mongolia, Jilin, Liaoning, Heilongjiang, Shaanxi, Gansu, Ningxia, Qinghai, and Xinjiang, where environments are fragile. In recent years, the eco-environmental problems such as vegetation destruction, desertification and soil erosion etc. become serious because of climate change and unreasonable human activities. In this paper, landscape pattern and its evolution in northern China from 1989 to 2003 was investigated by the combined use of RS and GIS based on the basic theory and method of landscape ecology. Land use/cover maps of the study area in 1989, 1999 and 2003 were produced by using 1 km monthly NOAA Ad-vanced Very High Resolution Radiometer (AVHRR) and SPOT/VGT Normalized Difference Vegetation Index (NDVI) dataset from national climate bureau of China which were geo-registered to Lambert azimuthal equal-area map projection and were used in the paper. Landscape evolution in the area over the study period was investigated by two methods: (a) the changes of various landscape metrics were analyzed using the landscape structure analysis program FRAGSTATS; (b) the transition matrix of landscape patch types was cal-culated with the help of the RS and GIS software. The results showed that from 1989 to 2003, the landscape within the study area had undertaken a complicated evolution in landscape structure and composition. The diversity index and evenness index increased during the pe-riod, which means that the landscape pattern tended to be diversified and even. The fragmentation index of grassland, forestland and water areas also increased significantly. This showed that the distribution and structure of forestland, grassland and water areas had been changed greatly during the period, especially grassland which became more and more fragmentized, and its fragmentation index increased from 19.23% to 88.72%. The transitions of the landscape types were mainly shown by the changes among forestland, grassland and farmland, and grassland changing into unable land. Over the study period, grassland and water areas had decreased remarkably, accounting for 15% and 37% from 1989 to 1999 and 24.79% and 49.25% from 1999 to 2003 respectively. The grassland and water resources play an important role in the eco-environment and economic development of the region. So, they must be protected carefully. According to the analysis, we can conclude that the eco-environment in the study area is obviously degenerated due to unreasonable human activities and climate changes and some measures should be taken to combat the environ-mental degradation.  相似文献   

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“Stone runs” is the Falklands vernacular term for openwork boulder accumulations, which include extensive blockstreams like the famous Darwin “stone-river” and associated features such as stone stripes. Since the early 20th century, they have been interpreted as the product of a suite of periglacial processes, including frost-wedging, gelifluction, frost heave, frost-sorting and snowmelt runoff. Following a literature review, the results of recent field investigations of the valley-floor blockstreams of East Falkland are presented. Access to the internal structure of these forms provides evidence for the existence of a three-fold profile, with clear vertical size gradation presenting striking similarities with an inverted weathering profile. Micromorphological analyses, SEM, XRD, thin sections and grain-size analyses lead to the hypothesis of an alternative model of stone run formation. It is suggested that the material forming the stone run profile lato sensu (including the superficial pavement) is not of periglacial origin, but derives directly from the stripping and accumulation downslope of a regolith, possibly Tertiary in age and formed under subtropical or temperate conditions. The valley-floor stone runs should, therefore, be considered as complex polygenetic landforms that may have formed according to a six-stage scenario, including in situ chemical weathering, regolith stripping by mass movements, soil formation, further regolith stripping, downslope accumulation and matrix washing-out (all phases possibly achieved by the Early Quaternary). Periglacial reworking of the stone run material would have operated at a “final” stage, i.e. during Quaternary cold stages, with boulder bioweathering and limonite-staining operating during the temperate intervals including the present one. The suggested antiquity of the Falklands blockstreams is in accordance with Caine's pioneer interpretation of Tasmania blockfields and with recent analyses and cosmogenic datings of blockfields from Scandinavia and North America.  相似文献   

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ABSTRACT

In academic and policy discourse, the concept of urban resilience is proliferating. Social theorists, especially human geographers, have rightfully criticized that the underlying politics of resilience have been ignored and stress the importance of asking “resilience of what, to what, and for whom?” This paper calls for careful consideration of not just resilience for whom and what, but also where, when, and why. A three-phase process is introduced to enable these “five Ws” to be negotiated collectively and to engender critical reflection on the politics of urban resilience as plans, initiatives, and projects are conceived, discussed, and implemented. Deployed through the hypothetical case of green infrastructure in Los Angeles, the paper concludes by illustrating how resilience planning trade-offs and decisions affect outcomes over space and time, often with significant implications for equity.  相似文献   

18.
Many Mediterranean streams in arid and semiarid areas are naturally saline systems due to the presence of evaportic rocks of Miocene or Triassic origin. Despite the fact that these aquatic ecosystems are rare in Europe, they are common in southeast of Spain. The environmental constraints of these semiarid saline streams are imposed by both geological and climatic conditions. This paper is a compilation and summary of the principal results obtained from various studies on semiarid saline streams in the Iberian southeast. Available data for these typical environments in the region covers diverse issues such as those regarding their physical and chemical features, typology, biodiversity, community structure and ecosystem functioning, as well as different ecological and evolutionary aspects of their biota (e.g. ecophysiological responses, life cycles and phylogeography). Issues concerning the conservation of these habitats, such as the main human uses, impacts, threats and their management are also summarised. Finally, topics in need of further research are provided. The current knowledge of saline streams in southeastern Spain highlights the physical and ecological singularity of these environments, and their high conservation value. Saline streams are particularly interesting due to their halotolerant/halophilic biota and high number of rare and endemic species.  相似文献   

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This paper contributes to recent debates about whether urban policy discourses are transferable and what is at stake in their translation. It draws on discussion of Darwin (Northwest Territory, Australia), a tropical savanna location that the local government wants to promote as a 'creative city', without quite knowing what this might require. We discuss relevant debates on research knowledge construction, the creative city and the path-dependent character of neoliberal governmental objectives. We then turn to the geographical, demographic and cultural characteristics that make Darwin a challenging and distinct context for translation of global theories of creative city rejuvenation. As well as arguing a case for more nuanced, locationally specific, analysis of the capacity of places to embrace travelling policy discourses, we suggest ways in which creative city research can be refreshed through engaging with literatures on (post)colonial urban politics and intersections with policy initiatives other than those targeted at 'creative industries' per se . We systematically outline the particular challenges that tropical cities in remote locations provide to accepted wisdom about creativity-led urban planning.  相似文献   

20.
The authors surveyed a representative sample of the Norwegian population (N = 4077) to examine perceptions of biodiversity loss and management, the relative importance of biodiversity loss to other environmental issues, and perceived implications of biodiversity loss. The results showed that 50% of the sample population saw biodiversity as a reality and major environmental issue, and 75% recognized that biodiversity loss occurs. Biodiversity loss was perceived as a lesser global environmental problem than environmental toxins, climate change, air and water pollution, and loss of rainforest, despite the fact that these topics can be difficult to separate since biodiversity loss is a function of other environmental problems. Loss of biodiversity was seen to have negative impacts on people's relationship to the natural environment, to impact environmental resilience, to be at least partly human-induced, and to be an issue of importance and relevance to the general public, not merely to the scientific community. Self-reported levels of knowledge of environmental topics were associated with increasing concern about consequences of reductions in species diversity. The authors conclude that efforts to increase public support for biodiversity conservation can be strengthened by increased emphasis on aesthetic, emotional and cultural aspects of biodiversity.  相似文献   

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