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101.
我国城市化进程中质与量关系的辩证分析   总被引:5,自引:0,他引:5  
城市化战略是中国21世纪经济社会发展的必然选择。根据城市发展规律,我国城市化进程已经进入一个全新的发展阶段。该文运用唯物辩证法质量互变规律,在探讨城市发展中质与量的辨证关系、剖析我国城市化现状的基础上,针对城市化进程中存在生态问题严重、城市功能下降、城乡矛盾突出等质量问题,强调指出,走质量效益型城市化道路是新世纪我国城市发展的必然选择。同时提出了优化环境质量、提高产业质量、强化城市建设、增强人口素质和提升城市文化等提高城市化质量的途径和方法。  相似文献   
102.
Reliable and up-to-date urban land cover information is valuable in urban planning and policy development. Due to the increasing demand for reliable land cover information there has been a growing need for robust methods and datasets to improve the classification accuracy from remotely sensed imagery. This study sought to assess the potential of the newly launched Landsat 8 sensor’s thermal bands and derived vegetation indices in improving land cover classification in a complex urban landscape using the support vector machine classifier. This study compared the individual and combined performance of Landsat 8’s reflective, thermal bands and vegetation indices in classifying urban land use-land cover. The integration of Landsat 8 reflective bands, derived vegetation indices and thermal bands overall produced significantly higher accuracy classification results than using traditional bands as standalone (i.e. overall, user and producer accuracies). An overall accuracy above 89.33% and a kappa index of 0.86, significantly higher than the one obtained with the use of the traditional reflective bands as a standalone data-set and other analysis stages. On average, the results also indicate high producer and user accuracies (i.e. above 80%) for most of the classes with a McNemar’s Z score of 9.00 at 95% confidence interval showing significant improvement compared with classification using reflective bands as standalone. Overall, the results of this study indicate that the integration of the Landsat 8’s OLI and TIR data presents an invaluable potential for accurate and robust land cover classification in a complex urban landscape, especially in areas where the availability of high resolution datasets remains a challenge.  相似文献   
103.
ABSTRACT. Political dimensions of conservation abound. The biosphere-reserve model, however, depoliticizes the landscape by neglecting politics as a shaper of ecologies. To illustrate this process of depoliticization, I examine discourses about environmental degradation, power structures engaged in implementing conservation measures, and emerging landscapes in the Maya Biosphere Reserve. Conservationist discourses hold migrant farmers responsible for deforestation and land degradation in the Petén, to the neglect of wider socioeconomic conditions that perpetuate poverty in Guatemala. Sociospatial consequences include misdirected projects and landscapes that reflect the goals of nongovernmental organizations, not local people's needs and aspirations.  相似文献   
104.
ABSTRACT. Students of human landscapes often view those landscapes as documents and seek to “read” them for cultural and historical meaning. But how does one learn to read landscape? And how can students be taught to do it? After many years of teaching courses about commonplace American landscapes, I have discovered that students must learn two things before they can expect to read human landscapes. First, they must learn to pay attention to commonplace things which most Americans normally ignore. Second, they must master vocabularies that permit them to classify elements in the landscape and to connect small things with larger ideas. Two examples in the landscape of Bellefonte, Pennsylvania—the town's war memorial and a scattering of California bungalows-demonstrate how these ideas work.  相似文献   
105.
本文将辩证思维方法运用于西安地裂缝研究中,阐述了西安地裂缝的时空观和间隙性,指出地裂缝的活动和地震没有必然的联系,同时也不足以抑制一次大震的发生。  相似文献   
106.
山地多民族地区农业文化景观的演变与当地地理空间的复杂性和民族文化的多样性特征密切相关。运用遥感、GIS技术,并结合田野调查,点面结合,分析了西双版纳傣族自治州橡胶文化景观的空间格局及其对民族关系的影响。研究表明:受全球化的影响,西双版纳地区传统稻作文化正逐渐式微,因经济利益驱使导致橡胶种植面积急剧扩大,土地利用方式改变,这是橡胶文化景观兴起的主要空间演化机制。橡胶文化在给当地少数民族带来丰厚经济收入和促进现代化发展的同时,也造成了生态多样性的破坏,民族特色经济、文化的损害,民族发展互补性的减少以及民族经济共生关系的打破。民族感情和民族认同让位于经济利益,民族乡土社会结构受到冲击,民族共生关系受到影响,这些都集中体现在橡胶文化景观上。通过研究文化景观演变与民族关系的关联,可以丰富人地关系理论的内涵,引入民族因素和文化因素来思考民族地区人地关系,扩展当今全球化变革影响下民族地理学研究的内容,同时也在实践上为做好民族工作和构建新型和谐民族关系提供新的思路。  相似文献   
107.
This paper explores the role of so-called wine trails as planners and managers of viticultural landscapes, using the case of the Finger Lakes region in New York, USA. Using key informant interviews, it assesses the current capacity and the future potential of these non-governmental, fee-based ‘clubs’ to mediate between global markets and the local agricultural landscape in the absence of policy frameworks designed for this purpose. Though it finds little evidence of such mediation today, the paper argues that the structure and institutional position of wine trails, organizations whose members’ livelihoods depend substantially on long-term landscape coherence, position them to play a more assertive role in doing so in the future, particularly in places marked by lax planning regimes and scarce resources.  相似文献   
108.
Biodiversity decline continues apace across the Australian landscape with a pressing need to redesign land use to address this situation. The significance of private land increasingly is recognised for the protection and enhancement of biodiversity as landholders inevitably make decisions that affect environmental quality. Biodiversity conservation is as much a social process as a physical one. Conservation covenants are perpetual agreements under which landholders choose to conserve land voluntarily, primarily for conservation purposes. The role covenants might play in landscape-scale conservation was investigated in north-western Victoria. In-depth interviews with a range of participants were undertaken, with an emphasis on the role covenantors might play as social learning and cultural change agents. Analysis of these interviews offers useful perspectives for understanding socio-cultural dimensions of landscape change and exploring the differing values of production farmers and nature conservation landholders. Consideration is then given to approaches to engaging local production farmers in nature covenants and promoting communication between this group and the largely non-production conservationists who currently form the mainstay of conservation covenants.  相似文献   
109.
Hypsometry of glaciated landscapes   总被引:1,自引:0,他引:1  
Hypsometry (frequency distribution of elevations) is often used to characterize landscape morphology, traditionally in the context of the degree of ?uvial dissection. Recently, the hypsometry of glaciated regions has been used to infer how rates of glacial erosion compare with tectonic uplift rates. However, many factors other than tectonics can also exert a major in?uence on the hypsometry of a glaciated landscape, resulting in a wide variety of hypsometries. Using examples from the eastern Sierra Nevada, California, the western Sangre de Cristo Range, Colorado, and the Ben Ohau Range, New Zealand, we demonstrate that, all else being equal, the hypsometries of neighbouring basins can indicate the relative degree of glacial modi?cation in each. A selection of drainage basins from the Rocky Mountains shows that the position of the equilibrium line altitude (ELA) within the drainage basin relief is a dominant variable in determining the hypsometry of a glaciated basin. This is a non‐linear effect: once the ELA falls to some critical level, the glaciers scour deeply below the ELA, causing a noticeably different hypsometry. The hypsometry of an arbitrary region encompassing many drainage basins can disguise the variation present in the hypsometries, and thus landforms, of the individual basins. Unique local circumstances, such as the presence of a mountain ice?eld (Waiho Basin, Southern Alps), substantial hanging valleys (Avalanche Creek, Glacier National Park), a narrow outlet canyon (Sawmill Creek, Sierra Nevada), and isolated geologic structures (Baker Creek, Sierra Nevada), can have a major impact on the hypsometry of an individual basin. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
110.
Gavin J Andrews 《Area》2004,36(3):307-318
Although the concept of therapeutic landscapes has assisted health geographers to explore the intimate connections between well-being and place, arguably, after a decade of applications, the common interpretations and assumptions of commentators should be reviewed. Based on theoretical insights from psychoanalytic geographies and geographies of nursing, this paper makes two observations. First, that landscape has been almost exclusively interpreted in a physical sense with co-presence being a necessary condition. In turn, this assumption has led to the neglect of non-physical (imagined) places. Second, that therapeutic effects have been interpreted as experiences attained outside of clinical practices. Hence, healthcare workers and their direct treatments and care have also been neglected. To explore these omissions together, an interview survey of complementary therapists investigates the many ways in which imagined places are constructed and manipulated in therapy sessions. Arguably, beyond this example, extending the therapeutic landscape concept to both physical and non-physical features of treatments could provide fresh insights into the dynamics between healthcare and place. In disciplinary terms, the benefits are twofold. Whilst it could help develop a critical tradition in health geography, perhaps ironically, it could also provide a stronger disciplinary connection between qualitative health geography, various forms of medicine and their research traditions.  相似文献   
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