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941.
Sedona, Arizona, an amenity town that trades on intangible quality-of-life attributes like spectacular scenery, the arts, and its nonmetropolitan location, has a conflict between low-wage employment catering to its tourist sector and expensive housing for its affluent residents. Many of those who work in Sedona do not live in the community. This study, based on a survey of 286 employees, shows that workers who live in Sedona do not have incomes that are significantly higher than commuters from the outside, but they live in housing that is almost twice as expensive. Employees who live in Sedona pay dearly for housing in order to be near jobs, natural beauty, and the cultural ambience of an amenity town. Commuters, on the other hand, incur high travel costs but enjoy cheaper housing and the lifestyle of small towns and rural areas. The emergence of amenity environments and long-distance commuting in Sedona is symbolic of the increased differentiation of nonmetropolitan landscapes. 相似文献
942.
944.
Howard Veregin 《The Professional geographer》1994,46(1):10-18
This essay questions the effectiveness of nuclear winter modeling as a means of impacting nuclear policy and changing public attitudes about nuclear issues. In nuclear winter modeling, humanistic concern over the possibility of global environmental destruction is cloaked in the ostensibly neutral language of science. Nuclear winter modeling attempts to apply rational argument to an issue that is rooted instead in human affect and morality. The implications of this misappropriation are discussed in terms of the dehumanizing nature of the images conjured up by nuclear winter, its attention to the effects of nuclear weapons rather than deeper structural problems, and its political ambiguity as a function of unresolvable uncertainty in model results. 相似文献
945.
946.
西藏农牧区农户土地决策与土地覆被变化研究 总被引:2,自引:0,他引:2
调查农户土地决策,均质化处理农户决策因子,形成土地决策空间图;制作土地覆被图和农户土地决策空间图,通过图像叠加处理,来分析土地覆被变化与农户土地决策度政策因子间的空间联系。西藏农牧区案例研究结果表明:农户土地决策决定了土地覆被变化方向,政策因子起修正作用;农户土地决策与土地覆被在空间上和属性上能互相体现;农牧区政策的制定应立足于农户土地决策,在满足农户追求最大经济效益的基础上引导农户顾及生态环境建设;农户土地决策、社会经济发展政策与土地覆被在空闻上能互相体现,可通过观察土地覆被变化来监测农户土地决策及政策因子效果。 相似文献
947.
Kirat Kamal Sampang Rai 《湿地科学》2006,4(2):87-90
Traditional culture bears a dynamic,cosmologi-cal vision in the wetland ecology and its biodiversityconservation in Nepal.The role of culture and rela-tionship in wetland biodiversity protection and wiseuse has not well been documented yet.Wetlands likeri… 相似文献
948.
Albert A. Bartlett 《Natural Resources Research》2006,15(3):151-164
This paper examines the implications of statements by Australia’s Minister of… Resources that Australia’s exports of coal
are growing rapidly and that Australia’s coal will last “110 years at current rates of production.” If one assumes that coal
production P(t), follows a Gaussian curve (similar to a Hubbert curve) one can construct a family of Gaussian curves showing possible future
paths of P(t) which are consistent with the cited “110 years.” Each curve reaches a maximum after which P(t) declines toward zero. Knowledge of the present value of dP/dt allows one member of the family to be identified as the most probable future path of P(t). Families of curves and tabular data are presented for resource quantities that would last 50, 100 and 200 years “at current
rates of production.” If, instead, Australia’s P(t) follows a declining exponential curve (exp(−kt)) with k = (1/110) per year, the stated quantity of coal will allow production to continue forever, with P(t) declining with a half life of 76 y. This and more rapidly declining exponential paths are the only paths that can be said
to be sustainable. The envelope of the family of Gaussian curves divides the (P, t) plane into “allowed” and “forbidden” areas.
The declining exponential curve divides the “allowed” area into an upper area that is “terminal” and a lower area that is
“sustainable.” These facts, coupled with Australia’s expectations of rapid growth of its population, suggest that Australia’s
present resource policies are “anti-sustainable” and that the people of Australia need to rethink their present policy of
rapidly exporting their fossil fuels. 相似文献
949.
'Gluttony or sloth': critical geographies of bodies and morality in (anti)obesity policy 总被引:1,自引:0,他引:1
Bethan Evans 《Area》2006,38(3):259-267
In many countries, obesity is high on public health policy agendas, and geographical research has begun to engage with obesity. However, obesity is a highly contested term, and recent debates about geographers' engagement with policy, and critical discussions of the presence of bodies in medical geography, bear great relevance for developing a critical perspective on dominant 'obesity discourse'. Through a critical reading of a recent UK policy document, this paper considers the presence of bodies in (anti)obesity campaigns, calling for a more critical approach to the medicalization of body size to be central to future geographical work on obesity. 相似文献
950.
Good, bad or 'necessary evil'? Reinterpreting the colonial burning experiments in the savanna landscapes of West Africa 总被引:2,自引:0,他引:2
A simple ecological model underlies contemporary fire policy in many West African countries. The model holds that the timing (or seasonality) of annual savanna fires is a principal determinant of vegetation cover. The model's origin can be traced to the ideas held by influential colonial scientists who viewed anthropogenic fire as a prime force of regional environmental degradation. The main evidence in support of the model derives from the results of a series of long-term burning experiments carried out during last century. The experimental results have been repeatedly mapped onto fire policy often taking the form of a three-tiered model in which fire exclusion is considered the ultimate management objective, late dry-season fire is discouraged and early dry-season fire is allowed but only under specific, often state-controlled circumstances. This paper provides a critique of contemporary fire policy in the region and the fire ecology model on which it is based. Through an analysis of burn scars for the 2002–3 fire season generated from ETM+ imagery, the study documents the spatiotemporal pattern of burning for an area in southern Mali. It argues that current policy, which is informed by an a-spatial model, cannot adequately account for the critical pattern of burning that is characteristic of the region. A reinterpretation of the burning experiments is presented in light of four factors: empirical data; recent developments in patch-mosaic theory; historical evidence on the effects of fire suppression; and data on indigenous burning strategies, all of which suggest a need to reconsider current fire policy. 相似文献