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Aidan Davison   《Geoforum》2008,39(3):1284-1295
The number and range of contests over the social production of nature is growing. Much environmentalist discourse, however, continues to appeal for unequivocal scientific support on clearly demarcated issues of pure, a-social nature. This paper explores the question of how participants in environmental movements view this demarcation in the context of their own lives. After introducing scholarly critique of dualistic ideas of nature and the ambivalence characteristic of environmentalist conceptions of nature, the paper draws upon a qualitative study with environmentalists in the Australian cities of Melbourne, Perth and Hobart. Inquiring into the interplay of discourse of nature and everyday worlds, interviews revealed a complex interdependence of dualistic and non-dualistic understandings of nature. This ecology of ideas was especially evident in spatial imaginaries of nature. Scientific terminology, social disaffection and pessimism were associated with abstract and mutually exclusive conceptions of society and nature. Reflections on personal experience, however, indicated more flexible and hopeful negotiations in everyday liminal spaces offering ‘the best of both worlds’. It is concluded that environmentalist resistance to dismantling of conceptual boundaries between society and nature may often stem not from failure to appreciate socionatural complexity, but from a strongly felt sense that the self can only truly be found in nature.  相似文献   
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Fish assemblages from two beaches, one in the inner and the other in the outer Sepetiba Bay (latitude: 22°54′–23°04′S; longitude: 43°34′–44°10′W), Southeast Brazil, were sampled by beach seine net, simultaneously, on both seasonal and diel scales, between August 1998 and June 1999. Sites were selected to encompass different environmental conditions which reflect the two bay zones, thus providing a comprehensive assessment of the factors influencing surf zone fish assemblages, and their spatial, seasonal and diel variations. A total of 55 fish species was recorded, mostly young-of-the-year. Anchoa tricolor, Micropogonias furnieri, Gerres aprion, Diapterus rhombeus, Harengula clupeola, Atherinella brasiliensis and Mugil liza were numerically dominant and contributed to 95.2% of the total fish catches. Strong differences in fish assemblages were observed between the two areas, with higher number of species in the outer bay. Increases in fish numbers occurred in winter, while the highest biomass occurred in winter and summer. Transparency, followed by salinity, was responsible for most of the spatial variability and played an important role in structuring fish assemblages. Overall, diel patterns did not reveal any significant trends; however, if we consider each season separately, an increase in fish numbers during the day with peak at sunset was observed in winter, and a higher biomass occurred at night in winter and summer. Species preferences for various combinations of environmental variables are responsible for shifts in the structure and overall abundance of assemblages and dictated some patterns. The sciaenid M. furnieri, the second most abundant species, occurred only in the inner zone, being more abundant in winter. The species of Engraulidae were more abundant in the outer zone in winter/spring during the day. The gerreids G. aprion and D. rhombeus occurred mainly in summer. Overall, temporal fluctuations act more at a specific level than at a structural one, and may be linked to some particular stages of the fish life cycle, but do not significantly influence the spatial organization.  相似文献   
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Mark Wise 《Area》2006,38(2):204-212
This paper calls for more analysis of contemporary transnational linguistic movements. Geographers have hitherto focused on linguistic problems within states and paid less attention to issues that arise as languages, notably English, are used internationally across state boundaries. It does this by examining a conflict that arose when forces integrating the supranational European Single Market space came into conflict with a Member State's determination to protect the linguistic 'integrity' of its national territory. This conflict would appear to be a precursor of similar ones to come as languages increasingly compete in a linguistic market within an integrating Europe and a globalizing world.  相似文献   
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The formation of cold air drainage flows in a shallow gully is studied during CASES-99 (Cooperative Atmosphere-Surface Exchange Study). Fast and slow response wind and temperature measurements were obtained on an instrumented 10-m tower located in the gully and from a network of thermistors and two-dimensional sonic anemometers, situated across the gully. Gully flow formed on clear nights even with significant synoptic flow. Large variations in surface temperature developed within an hour after sunset and in situ cooling was the dominant factor in wind sheltered locations. The depth of the drainage flow and the height of the down-gully wind speed maximum were found to be largest when the external wind speed above the gully flow is less than 2 m s-1. The shallow drainage current is restricted to a depth of a few metres, and is deepest when the stratification is stronger and the external flow is weaker. During the night the drainage flow breaks down, sometimes on several occasions, due to intermittent turbulence and downward fluxes of heat and momentum. The near surface temperature may increase by 6 ° C in less than 30 min due to the vertical convergence of downward heat flux. The mixing events are related to acceleration of the flow above the gully flow and decreased Richardson number. These warming events also lead to warming of the near surface soil and reduction of the upward soil heat flux. To examine the relative importance of different physical mechanisms that could contribute to the rapid warming, and to characterize the turbulence generated during the intermittent turbulent periods, the sensible heat budget is analyzed and the behaviour of different turbulent parameters is discussed.  相似文献   
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The Hida marginal belt (HMB), which consists of various kinds of fault-bound blocks, is located between the continental massif of the Hida belt and the Mesozoic accretionary complex of the Mino belt in Central Japan. Detailed field investigation reveals that the HMB had grown through the two different movements, i.e., Jurassic dextral and Cretaceous sinistral movements. The Jurassic dextral ductile shear zones run in the southern marginal part of the Hida belt and the northern part of the HMB, whereas the Cretaceous sinistral cataclastic shear zones occur in the southern part of the HMB and the northern marginal part of the Mino belt. Geologic map and field evidence seem to suggest that the Jurassic dextral movement form the fault-bound blocks of the HMB to form the basic structure of the Hida marginal belt, i.e., formation of the ‘proto-HMB.’ Following the dextral movement, the sinistral one restructured the ‘proto-HMB’ to complete the present feature of the Hida marginal belt. The Cretaceous sinistral movement might result in the sinistral collision between the proto-HMB and the Mino belt.  相似文献   
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Least-squares prediction using an empirically deduced local covariance function was performed to investigate the temporal change in the rates of vertical crustal movements in the Tohoku district, Japan. Levelling data covering an area of approximately 450 × 275 km2 observed between 1966 and 1995 were used and the results shown in the form of contour maps. Firstly we derived a covariance function of the rates of vertical crustal movement with a Gaussian form function. We used this function to estimate the spatial distribution of the rates of vertical crustal movements. By the present method, a steady tilt of the Tohoku district to the east, toward the Japan Trench and an areal uplift in the southwestern part were well reproduced. Moreover, a significant temporal change in vertical movement rates is clearly seen. Received: 15 July 1996   相似文献   
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Crack widths and rock temperatures were monitored on an andestic bedrock cliff in the summit area of the Daisetsu Mountains, Hokkaido, northern Japan. Sequential data recorded the gradual widening of a crack to the point of critical crack extension, which resulted in catastrophic rock breakage. The data indicate that a combination of liquid water in?ltration into crack tip and subsequent freezing is the most signi?cant factor contributing to critical crack extension. The recorded sub‐critical crack movements involved a number of minor crack extensions and contractions, the timing of which correlates well with the magnitude of the reconstructed thermal stresses at the crack tip derived from thermal deformation of the plate‐shaped rock fragment. Larger crack extensions occurred when stress at the crack tip exceeded a threshold value, possibly re?ecting the control of rock fracture mechanics by which cracks are thought to propagate when the stress intensity factor at the crack tip exceeds the threshold values for stress corrosion cracking and the fracture toughness of the material. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
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