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251.
LILi-mei TAOWei 《中国地理科学(英文版)》2003,13(4):370-377
The growing attention on urban tourism was very widespread. There are two angles to study urban tourism: supply-side and demand-side. And the supply-side of the tourism remains very important. The RBD (Recreation Business District) is a useful framework to understand the components of urban tourism and how they fit together. The paper begins with a review on the RBD and the spatial structure of tourism in urban areas and then attempts to develop a more general understanding of the spatial structure evolution of RBDs in a tourist-historic city—Suzhou. The spatial structures and functions of the RBDs in Suzhou are examined, based on field observations, interviews with city officials and industry leaders, and a review of available documents. The urban tourism of Suzhou has developed in a range of contexts, that various types of RBDs have emerged as a result of different urban development strategies. The spatial structure has evolved from the past “Single-cored Structure“ to “Double-cored Structure“ at present, and then to “Chain Structure“ in the future. The spatial form and evolution of RBD in Suzhou are closely relative with its urban spatial expansion. Urban area dispersal is the prerequisite of the emergence of the RBD. Planning and constructing the RBD becomes a new impetus to urban growth or renewal. Finally, a number of strategies for planning and developing the RBD in Suzhou are suggested. The different RBDs should adopt different strategies.Intensification can be the possible strategy for the RBDs in the ancient city. Accreting with the urban theme park or engrafting on the Jinji Lake is suggested respectively for the RBD in the Suzhou New District and the Suzhou Indus-trial Park. 相似文献
252.
昆明市东川城区后山泥石流灾害修复措施 总被引:3,自引:0,他引:3
东川城区后山构造发育、地震频繁、山体失稳、地形高差悬殊和雨量集中且暴雨强度大等,是导致本区泥石流频繁而猛烈的根本原因。人类不合理的经济活动则对本区泥石流的发生发展起着重要的加剧、恶化作用。对东川城区后山泥石流的治理必须采用软件和硬件两大措施相结合的综合治理办法,并对治理过的泥石流沟加强管理力度。 相似文献
253.
大城市边缘外来人口的空间集聚与重构——以上海市闵行区为例 总被引:2,自引:0,他引:2
外来人口集聚模式和演化过程是考察外来人口空间行为的重要量度指标,通过量度外来人口的空间集聚,可以更好地构建城市社会空间的优化模式,从而为构建和谐社会提供理论依据和实践性总结。大城市边缘区外来人口具有与城市中心不尽相同的特征,解析这些特征是研究外来人口空间分布和空间行为的重要基础。文章主要分析了上海市闽行区外来人口的基本特征与集聚成因,较为详尽地论述了外来人口的空间集聚基本形式与演化过程,并在此基础上提出大城市外来人口的重构模式。 相似文献
254.
255.
东兴区地质灾害数量众多,分布广泛,危害严重,以小型崩塌(危岩)为主。主要分布在区域东北部、西北部窄谷深丘地貌区及中南部人口相对密集地区。即地质灾害中易发区;其发生时间多集中在每年7~9月。地质灾害发育分布受多种因素控制及影响。即地形地貌控制着地质灾害的规模及空间分布;软硬相间的岩性组合易产生差异性风化,引起斜坡失稳;近水平的地质构造可产生大量的斜坡失稳;斜坡结构形式控制着崩塌(危岩)发生的可能性;降雨使岩体受到冲刷及软化并且在岩体内部产生水压力,促进斜坡失稳;人类工程活动导致斜坡原始状态破坏,诱发斜坡失稳。根据地质灾害的发育分布特征及控制和影响因素,建议采取治理与避险搬迁、加强监测以及保护斜坡地质环境等措施减少地质灾害的发生。 相似文献
256.
Dario Visonà Anna Maria Fioretti Maria Eliana Poli Adriano Zanferrari Mark Fanning 《Swiss Journal of Geoscience》2007,100(2):313-324
The Athesian Volcanic District (AVD), a thick sequence of andesitic to rhyolitic lava and ignimbrite, overlies both the Variscan basement of the Dolomites and, where present, the continental basal conglomerate of Upper Carboniferous(?) to Early Permian age. This volcanic activity is known to mark the margin of the intra-Pangea megashear system between Gondwana and Laurasia, the onset age of which is determined in this study.SHRIMP U-Pb dating on zircon from Ponte Gardena/Waidbruck (Isarco/Eisack valley) basaltic andesite yields an age of 290.7 ± 3 Ma, providing the oldest record of andesite volcanic activity yet documented in the AVD. Two younger dates (279.9 ± 3.3 and 278.6 ± 3.1 Ma) obtained for the andesitic necks of M. dei Ginepri (Eores/Aferer valley) and Col Quaternà (western Comelico), respectively, probably represent a second pulse of andesite magmatic activity.Near Chiusa/Klausen, the volcanoclastic deposits at the bottom of the Funes/Villnöss valley volcano-sedimentary complex only contain detrital zircons, dated at 469 ± 6 Ma; these probably derive from erosion of Paleozoic porphyroids. Other zircons from the same sediments and inherited cores of magmatic andesite crystals give Paleoproterozoic (1953.6 ± 22.1, 1834.6 ± 69.3, 1773.6 ± 25.1 Ma), Early Neoproterozoic (1015 ± 14 Ma) and Late Neoproterozoic (728.4 ± 9.6, 687.6 ± 7.6 Ma) ages. These ancient detrital and inherited zircon ages fit the model that envisages the Dolomite region as being tectonically coherent with Africa, at least until the Lower Permian. 相似文献
257.
我国大经济区的研究与实践 总被引:1,自引:0,他引:1
李振泉 《云南地理环境研究》1991,3(1):6-14
经济区是客观存在的,是在经济发展过程中形成的。但我国经济区一直未能正常、稳定地形成和发展,是认识和体制上的障碍。划分大经济区要着眼远景发展方向;照顾自然区域单元的完整性和自然资源的协调性;考虑经济结构相对完整和专业化特点突出,要有大的经济中心和统一的交通运输网络;适当照顾行政区和民族自治区的完整性等原则。对比众家方案,从而提出把我国划分为东北、华北、华东、华中、华南、西南、西北、新疆、西藏九大经济区的新方案。 相似文献
258.
《中国地理科学(英文版)》2001,(4)
IREGIONAL BACKGROUND AND RESEARCH W6St to 68St,dlVld6S th6 Whol6 distriCt lflto tWO pdrts.METHODS The Huangshul River,the Zhuanglang River and theXlanshul River respectively low Into the Huanghe Riverl.IReglonalBackground Inthe west and northdthe region.The whole geo-morphology of*thelogy region Is that nofth Is much lowerInknzhou City,Xlgu District,、hlch covers an than south,but both a… 相似文献
259.
Derek A. McDougall 《第四纪科学杂志》2001,16(6):531-543
Detailed geomorphological mapping has revealed evidence for the development of plateau icefields in the central fells of the English Lake District during the Loch Lomond (Younger Dryas) Stadial (ca. 12.9–11.5 ka). The largest plateau icefield system, which covered an area of approximately 55 km2 (including outlet glaciers), was centred on High Raise. To the west, smaller plateau icefields developed on Grey Knotts/Brandreth and Dale Head, covering areas of 7 km2 and 3 km2 respectively. The geomorphological impact of these plateau icefields appears to have been minimal on the summits, where the survival of blockfields and other frost‐weathered debris (mostly peat‐covered) implies the existence of at least patches of protective, cold‐based ice. Ice‐moulded bedrock at some plateau edges, however, documents a transition to wet‐based, erosive conditions. Prominent moraine systems were produced by outlet glaciers, which descended into the surrounding valleys where their margins became sediment traps for supraglacial debris and inwash. In some valleys, ice‐marginal moraines record successive positions of outlet glaciers, which actively backwasted towards their plateau source. This interpretation differs from that of previous workers, who assumed an alpine style of glaciation, with reconstructed glaciers emanating from corries and valley heads. It is likely that plateau icefields were more common at this time in upland Britain than hitherto has been appreciated. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
260.
对江宁区境内露采矿山现状作出了总结。指出了江宁区露天矿山开采存在的主要问题。对江宁区露采矿山的地质环境现状进行了分析。提出江宁区露采矿山地质环境的整治措施。 相似文献