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关于香港人口的分布与其土地利用问题的意见 总被引:2,自引:0,他引:2
概述了香港人口分布和土地利用现状的特点 ,根据香港的土地利用特点 ,结合香港地势图分析 ,全区的土地利用以城市用地为主 ,主要利用沿海冲积 -海积平原和坡地。文中针对高台地和斜坡地利用提出一些新意见 ,务求全体香港市民不受滑坡的威胁。 相似文献
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DON BIDDLE 《The Australian geographer》1999,30(1):75-92
In Australia, geography, studied as a discipline, is generally non-existent in Grades K-6 (approximately ages 5-11 years) and, in some states, this state of affairs extends to Grades 7-10 (12-15 years). In New South Wales (NSW), the geography component has been strengthened in the Grades K-6 curriculum; there are mandatory and optional geography courses in Grades 7-10, and optional geography courses in Grades 11 and 12 (16-17 + years). In this paper, the place of geography in NSW, in the learning area of Studies of Society and Environment, is compared with geography curricula in five countries. In England and Wales, and in Finland, geography is regarded as an essential subject in the school curriculum. In the USA and Japan, attempts are being made to replace generalist social studies courses with disciplines, such as geography, from the humanities and social sciences. And, finally, Hong Kong has been influenced by curriculum developments in England and Wales, as well as in Australia. 相似文献
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香港岛屿的形成与演变 总被引:1,自引:0,他引:1
经过野外考察和室内光弹实验等测试表明,香港地区岛屿的形成与演变机制,是以断裂构造为基础,海陆变迁为动力,形成的年代是全新世中期大温暖期高海面。 相似文献
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Analysis of rainstorm-induced slide-debris flows on natural terrain of Lantau Island, Hong Kong 总被引:21,自引:0,他引:21
Lantau Island, the largest outlying island of the territory of Hong Kong, experienced a severe rainstorm on 4–5 November 1993, which induced >800 slope failures on natural terrain there. Detailed field investigations were carried out to study the failure modes, in relation with various influencing factors. It was found that the occurrence of slide-debris flows has a close relationship with bedrock geology, slope gradient, vegetation cover and micro landform. The failure modes of slide-debris flows may be classified into translational slides and rotational slides, and the former are predominant. Analysis of the hydrological response of colluvial slopes during the rainstorm indicated that the majority of the failures were caused by the development of a perched water table in the thin surface layer of colluvium of volcanic origin due to infiltration during the heavy rain. Undisturbed soil samples from south Lantau have been subjected to anisotropically consolidated undrained compression tests at comparatively low stress levels. Constant deviatoric stress path tests (CQD) simulating the stress path in the field at in situ stress levels have been performed to investigate soil behavior. The CQD test results indicate that the material of slopes at undisturbed state is brought to dilation because of the increase in pore water pressure caused by infiltration of rain water. For a translational slide, the displacement, resulting from dilation, may destroy cohesion along the failure surface and locally within the interior of the slide. The surplus water during the intense rainstorm was able to equilibrate the reduction in pore pressure caused by dilation, and the dilation and displacement may be further increased. The strain-softening after significant strains triggered debris flow mobilization. However, for a rotational slide, the increase in pore water pressure caused by surplus water infiltration during the intense rainstorm could not equilibrate the reduction in pore pressure caused by dilation, much or even all of the sliding block could not mobilize into a debris flow. 相似文献
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