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971.
城市环境影响评价是城市规划与可持续发展中的一个重要问题.从规划部门对设计方案进行分析比较、定量评估的实际需求出发,采用地理信息数据处理与模拟等技术,归纳了GIs的评估指标体系.针对城市总体规划方案,将GIs数据引人气象模型,建立城市规划气象GIs论证评价技术路线;对规划方案进行空间概化、划分并识别单元特征,通过土地利用...  相似文献   
972.
This review summarizes the general developments of the operational mesoscale modeling based on the Global/Regional Assimilation and Prediction System-Tropical Monsoon Model (GRAPES-TMM) at the Guangzhou Regional Meteorological Center. GRAPES-TMM consists of the Tropical Regional Atmospheric Model System for the South China Sea (TRAMS, a typhoon model with a horizontal resolution of 9 km), the Mesoscale Atmospheric Regional Model System (MARS, 3km) and the fine-scale Rapid Update Cycling (RUC, 1km) forecasting system. The advances of model dynamical core and physical processes are summarized; the progress of model applications is reviewed and evaluated. The results show that the updated 9-3-1 forecasting system provides an overall improved performance on the weather forecasting in south China. Capabilities and limitations as well as the future development of the forecasting system are also discussed  相似文献   
973.
近年来,世界各地对世界遗产地旅游资源的开发步伐不断加快,随之而来的出现了很多问题,而其中如何持续有效的经营与管理世界遗产资源已成为亟待解决的首要问题。在对有关世界遗产地管理模式文献梳理的基础上,分析了中国现有世界遗产地管理模式以及存在的一些问题。针对这些存在的问题,笔者以绿色管理为基础对世界遗产地旅游管理模式进行了重构,并且列举了绿色管理在世界遗产地旅游管理模式中的作用,进而凸显绿色管理在世界遗产地管理中的重要性。  相似文献   
974.
中国城市化发展的紧凑度评价分析   总被引:9,自引:0,他引:9  
马丽  金凤君 《地理科学进展》2011,30(8):1014-1020
中国快速的城市化进程带来的城市空间扩张造成耕地面积减少以及能源资源消费与污染排放增长。20世纪60年代以来欧美国家紧凑型城市发展模式以其在有限的城市空间布局较高密度的产业和人口的特征,成为目前中国城市发展的选择。但是,由于中国的城市化发展道路和特征迥异于西方国家,因此关于紧凑城市"提高城市密度、促进土地利用的功能混合以及鼓励公交出行"的内涵,以及紧凑城市可以降低城市交通能源消费与污染排放、提高城市土地利用效率以及城市公共服务设施利用率的观点在中国是否可行,还需要仔细分析。在辨析中国所需要的紧凑城市内涵基础上,建立城市紧凑度评估指标体系,对中国120个地级及以上城市的紧凑度进行评估,并对其与资源利用和污染排放强度的相关性进行分析。研究发现,中国67.2%的城市处于不紧凑状态,城市的紧凑度与城市人口规模、经济规模没有很强的联系,与人均能源消耗以及污水排放的相关系数也比较低。究其原因,主要归结于中国城市化发展阶段、城市产业结构特征以及城市基础设施投资不足。本文还对中国需要什么样的紧凑城市,以及如何实现紧凑等进行了探讨。  相似文献   
975.
The essential purpose of the Convention Concerning the Protection of World Cultural and Natural Heritage is to protect the integrity of heritage values. Outstanding landscape is the core embodiment of the aesthetic value of a natural heritage site. This paper proposes a new assessment method from the point of view of the protection of heritage values. It is used to measure the degree of outstanding landscape integrity under the human and natural impact in natural heritage sites. This paper employ three indices, a visual index of outstanding landscape, a harmony index of the artificial landscape and a disturbance index of damaged landscape, to measure the impact of landscape integrity. The impact assessment model is based on a weighted combination of the three indices. The study site is the Fairy Valley, Kanas Nature Reserve, Xinjiang Uygur Autonomous Region in northwest China. The information employed is derived from field investigation and a Digital Elevation Model (DEM). A comprehensive evaluation of the Fairy valley was undertaken and it was determined that the outstanding landscape values are being compromised. Three protection methods are proposed to reduce the adverse effects and maintain landscape quality, thereby providing site managers with suggestions for the protection of natural heritage values. More broadly, the paper contributes novel methods of landscape assessment applicable to natural protected areas.  相似文献   
976.
977.
BOOK REVIEWS     
Book Reviewed in this article: The Vanishing Farmland Crisis, Critical Views of the Movement to Preserve Agricultural Land . John Baden Protecting Farmlands . Frederick R. Steiner and John E. Theilacker Ecological Effects of Fire in South African Ecosystems . Peter de V. Booysen and Neil M. Tainton Geography in China . Wu Chuanjun , Wang Nailiang , Lin Chao and Zhao Songqiao Resource Inventory and Baseline Study Methods for Developing Countries . Francis Conant , Peter Rogers , Marion Baumgardner , Cyrus Mc Kell , Raymond Dasmann, and Priscilla Reining Principles of Remote Sensing . Paul J. Curran Famine As A Geographical Phenomenon . Bruce Currey and Graeme Hugo The Suburban Squeeze: Land Conversion and Regulation in the San Francisco Bay Area . David E. Dowall Senses of Place . John Eyles Uneven Development and the Geographical Transfer of Value . D. K. Forbes and P. J. Rimmer Issues in Wilderness Management . Michael Frome Land-use and Prehistory in South-east Spain , The London Research Series in Geography 8. Antonio Gilman and John B. Thornes with Stephen Wise Regions in Question, Space, Development Theory and Regional Policy . Charles Gore The Colorado River: Instability and Basin Management . William L. Graf Hazardous Waste Sites: The Credibility Gap . Michael R. Greenberg and Richard F. Anderson Peasants, Subsistence Ecology, and Development in the Highlands of Papua New Guinea . Lawrence S. Grossman Silver Cities: The Photography of American Urbanization, 1839-1915 Peter B. Hales Silicon Landscapes . Peter Hall and Ann Markusen Remaking Ibieca: Rural Life in Aragon under Franco . Susan F. Harding The European Energy Challenge: East and West . George W. Hoffman The Global Climate . John T. Houghton The Urban Jobless in Eastern Africa . Abel G. M. Ishumi . The Tourist: Travel in Twentieth-Century North America . John A. Jakle City and Society: An Outline for Urban Geography . R. J. Johnston Residential Segregation, The State and Constitutional Conflict in American Urban Areas . R. J. Johnston Accessibility and Utilization: Geographical Perspectives on Health Care Delivery . Alun E. Joseph and David R. Phillips To the Heart of Asia: The Life of Sven Hedin . George Kish North American Culture , Vol 1. Ary J. Lamme III Past and Present in the Americas: A Compendium of Recent Studies . John Lynch Ethnicity in Contemporary America: A Geographical Appraisal . Jesse O. Mc Kee The Shell Countryside Book . Richard Muir and Eric Duffey 1990 Planning Conference Series. Proceedings of the National Geographic Areas Conference . Proceedings of the Regional Geographic Areas Conferences Wood, Brick, and Stone: The North American Settlement Landscape . Vol. 2: Barns and Farm Structures . Allen G. Noble Bangladesh: Biography of a Muslim Nation . Charles Peter O'donnell  相似文献   
978.
The legacy of repeated Pleistocene glaciations has endowed many Welsh river valleys with locally thick successions of glacial and alluvial sediments. Investigations of a well-preserved flight of terraced sediments with good exposures at Capel Bangor, on the Afon Rheidol, mid-Wales, has allowed its Quaternary valley fill stratigraphy to be examined in detail. Study has revealed five terraced fills consisting of seven distinct sedimentary units. These range from Late Devensian ice-contact and ice-marginal deposits, to Holocene high-sinuosity stream sediments with episodes of man-induced accelerated deposition of fine-grained alluvium, and to aggradation and subsequent incision associated with historic metal mining. Examination of general sedimentary properties (e.g., granulometry, sedimentary structures, terrace surface morphology) show both differences in the pattern and controls of deposition and also progressive changes over Late Devensian and Holocene times. The sediments of the Rheidol Valley record the response and subsequent recovery of a drainage basin to glaciation, and the increasing influence of man on sediment yields, channel processes, and sediment quality.  相似文献   
979.
光污染和光学天文台址保护   总被引:1,自引:0,他引:1  
讨论了天光背景对光学天文台的背景,综述了造成光污染的主要途径,介绍了防止光污染的几个主要国际组织和国际上对天文台址的保护立法,提出了减少污染的主要措施。为国内进行光学天文台址保护采取措施以至(国家的或者地方的)立法提供参考。  相似文献   
980.
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