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111.
20世纪90年代以来中外区域规划研究的对比分析 总被引:1,自引:0,他引:1
区域规划是国家政府进行区域管理的重要手段和方式之一。为了落实科学发展观和对区域发展有效宏观调控,区域规划成为国家“十一五”规划的重要内容。本文对比分析了1990年代以来国外区域规划研究的主要进展、以及我国区域规划研究的特点与不足,以期为推动我国当前新一轮区域规划的理论研究和实践创新提供有益启示。 相似文献
112.
1990~2005年间,是广州市经济快速发展和城市景观变化最大的时期,以同时段TM影像解译得到广州市的土地覆被类型图,从数量结构、空间信息及位置转移和景观等方面,分析了广州市土地覆被的动态特征.数量结构的研究结果显示:在快速城市化过程中广州市的耕地、林地等自然资源的利用程度在加大,自1995年起,这种变化的趋势开始减缓;土地覆被类型之间的信息与位置的转移变化频繁,并且表现出空间位置分异的特征.景观特征指数分析结果表明:广州市城市土地覆被向破碎化方向发展,城市建设用地呈扩展之势. 相似文献
113.
Based on the high temperature data of June to August in 1961-2000 in North China, the high temperature weather processes are investigated, and a more complete data set for severe high temperature processes is created. The climatic characteristics of adverse high temperature weather in Beijing, Tianjin, Shijiazhuang, Jinan and Taiyuan are analyzed respectively. The major features of the East-Asia Subtropical High and Transformed Continental High are discussed. The outcomes indicate that the influence of both East Asia Subtropical High and Transformed Continental High on these weather events varies, by a larger margin, from one city to another over North China and they are also closely related to the relative humidity. It is found that the behaviours of East-Asia Subtropical High and Transformed Continental High are the major important systems that give rise to the summer high temperature weather over the region. Based on these findings, the 5-day, 10-day and monthly assessment models for such high impact events have been developed. The assessment outcomes prove to be useful in assessing severe high-temperature events in major cities of North China. 相似文献
114.
Managing sustainable farmed landscape through 'alternative' food networks: a case study from Italy 总被引:1,自引:0,他引:1
LEWIS HOLLOWAY ROSIE COX† LAURA VENN‡ MOYA KNEAFSEY‡ ELIZABETH DOWLER§ HELENA TUOMAINEN§ 《The Geographical journal》2006,172(3):219-229
This paper focuses on a case study of an 'alternative' food network based in the Abruzzo National Park, Italy, to explore how ideas of sustainable farmland management can be expressed through broader understandings of developing networks of care concerned with local economies and societies, high-quality specialist food products, particular 'traditional' farming practices and livestock breeds, as well as the ecology of a farmed landscape. The scheme allows customers, internationally as well as in Italy, to 'adopt' a milking sheep on a large mountain farm. In return, adopters are sent food products from the farm. The adoption scheme is inter-twined with an agri-tourism project which provides accommodation, runs a restaurant and engages in educational activities. The scheme is the result of the individual initiative of its founder, and is associated with a strongly expressed ethical position concerning the value of sustaining valued local rural landscapes and lifestyles, and the importance of 'reconnecting' urban dwellers with rural areas, farming and 'quality' food production. Yet the localness of the scheme is sustained through wider national and international networks: volunteer and paid workers are drawn from several European countries, funding has been acquired from the EU LEADER programme, and internet and transport technologies are essential in connecting with and supplying an international customer base. The broader economy of care instanced in this case study draws attention to a need to develop strategies for sustainable farmland management constructed around wider programmes of social, economic and cultural, as well as environmental, concern. 相似文献
115.
分析了洪山预测区西部洪山岩体地质特征及其向外围扩散的范围和程度,研究了北掌勘查区和焦窑煤矿两邻区煤层受岩浆岩影响的程度,认为洪山岩体对预测区煤系及煤层赋存的影响较小,岩体外围仍有煤系赋存。为下一步找煤指明了方向。 相似文献
116.
通过对漳平市吾祠煤矿区的煤层地质构造特征分析,探讨了复杂构造条件下的矿井生产布局,主要是煤矿区段水平划分、煤炭采区的巷道布置、采煤方法及有关地质硐探等问题,对矿山开发有一定的指导意义。 相似文献
117.
我国水资源承载力研究现状及展望 总被引:1,自引:0,他引:1
概要说明了我国水资源承载力的研究现状,阐述了水资源承载力的概念、内涵及影响因素,探讨了目前几种常用的水资源承载力评价方法,并对当前研究中存在的问题进行了初步分析,进而提出了我国水资源承载力的研究趋势。 相似文献
118.
John R. Greenwood Joanne E. Norris Jo Wint 《Geotechnical and Geological Engineering》2006,24(3):467-481
The procedure for geotechnical site investigation is well established but little attention is currently given to investigating
the potential of vegetation to assist with ground stability. This paper describes how routine investigation procedures may
be adapted to consider the effects of the vegetation. It is recommended that the major part of the vegetation investigation
is carried out, at relatively low cost, during the preliminary (desk) study phase of the investigation when there is maximum
flexibility to take account of findings in the proposed design and construction. The techniques available for investigation
of the effects of vegetation are reviewed and references provided for further consideration. As for general geotechnical investigation
work, it is important that a balance of effort is maintained in the vegetation investigation between (a) site characterisation
(defining and identifying the existing and proposed vegetation to suit the site and ground conditions), (b) testing (in-situ and laboratory testing of the vegetation and root systems to provide design parameters) and (c) modelling (to analyse the
vegetation effects). 相似文献
119.
1 Introduction Alunite [KAl3(SO4)2(OH)6] is a very important non-ferrous metal resource, so many countries throughout the world have made great investments in research on the mechanism of its formation, its geological characteristics and applications. O… 相似文献
120.
本文提出了人为土的工程概念,从其成因的角度给出了人为土明确的科学定义,归纳和总结了人为土的基本特征,为人为土的工程分类体系建立、合理评价、工程利用和环境整治提供科学依据。 相似文献