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241.
通过对中国地理学在20世纪发展脉络进行了较全面、系统的回顾,在此基础上,对新世纪中国地理学的发展进行了展望。 相似文献
242.
Cleophas Lado 《Applied geography (Sevenoaks, England)》2004,24(4):281-302
This paper examines farmers’ ethnobotanical knowledge, innovation and rural change, and indicates one way in which indigenous technical knowledge complementing scientific knowledge may be documented for use by development planners and agencies. This paper firstly identifies plant species recognised as resources by farmers, and considers the value of these resources. Secondly, the paper documents and assesses the ethnobotanical knowledge associated with the utilisation of plant species, before turning to examine how plant resources are defined by use and culture. It also demonstrates that some components of ethnobotanical knowledge have potential for the sustainable development of plant species. The study shows that farmers have started to domesticate some of the ‘traditional’ plants, and new crops have been introduced associated with corresponding innovations in local agricultural systems. Since the farmers have a relatively strong tradition in natural resources conservation, this study suggests that it will be possible to introduce community-based gene banks linked to formal or government facilities. The paper demonstrates that it is important to combine and interweave ‘modern’ and indigenous knowledges to produce a more realistic and sensitive understanding and management of natural environmental resources for sustainable development. 相似文献
243.
Impacts of the forces and processes of agricultural restructuring are described in this paper through an analysis of farmers’ ‘lived experience’ in the tobacco sector of Ontario, Canada. The paper argues that the political and economic changes in the 1980s fundamentally altered tobacco farming and the broader rural community. The analysis is based upon a survey of farmers and former farmers, and includes examples of individual case histories. The results show the ways in which farmers’ well-being was affected and provides insights into coping mechanisms. 相似文献
244.
虚拟现实技术及其在地理学中的应用 总被引:5,自引:1,他引:5
虚拟现实是一项涉及计算机图形学、人机交互技术、传感技术、人工智能等领域的综合集成技术。它用计算机生成逼真的三维视、听、嗅觉等感觉,使人作为参与者通过适当装置,自然地对虚拟世界进行体验和交互,最终使得参与者产生身临其境之感。在分析虚拟现实定义及软件硬件构成的基础上,提出了虚拟地理环境的概念及其技术实施路线,探讨了现实技术在地理学中的应用前景。 相似文献
245.
Recent decades have seen the rural areas of developing and emerging countries undergo significant structural changes. They are the source of several pertinent international concerns, including extreme poverty and hunger, and rising spatial and interpersonal disparities, challenges that national governments and the international community have made limited headway in alleviating to date. By analysing the range of rural development approaches implemented in recent decades, we develop a picture in which territorial approaches have become more mainstream. Since the turn of the century in particular they have gradually supplanted more traditional place-neutral approaches, which, we argue, have served to increase rural-urban disparities and exasperate the incidence of poverty in rural areas. Rural territorial development approaches, where able to mobilise sufficient participation and coordination between local stakeholders, civil society, and various multi-level actors, offer the most favourable means of gaining a better understanding of the many social, economic, institutional assets within a region. They can be harnessed to drive brands of regional development that are not only sustainable, but also more equitable and inclusive across different segments of the population and territories. 相似文献
246.
MARGOT JESPERSEN M.Sc. ERIK RASMUSSEN M.Sc. 《Geografisk tidskrift / udgivet af Bestyrelsen for Det Kongelige danske geografiske selskab》2013,113(1):13-23
Jespersen, Margot und Rasmussen, Erik: Jordsand—Erosion und Akkumulation einer Hallig. Geografisk Tidsskrift 75: 13–23. København, juni 1, 1976. Since 1972 the authors have carried out investigations of erosion and accumulation on the island of Jordsand in the Danish Wadden Sea. The investigations supported by the Danish State Research Council for Natural Sciences are not yet finished, and this paper is a midway report including preliminary results and working hypotheses. 相似文献
247.
248.
民国时期中国地理研究所钩沉 总被引:1,自引:0,他引:1
中国地理研究所是中国地理学史上第一个地理学专门研究机关,1940年8月1日成立于重庆北碚,1950年4月以该所为基础成立中国科学院地理研究所筹备处。抗日战争时期抗战建国事业对地理人才的迫切需求、朱家骅对在中国发展地理学的大力提倡、管理中英庚款董事会息金收入的资金支持和近代以来地理学专门研究机构的缺失共同构成中国地理研究所成立的历史背景。成立后的中国地理研究所吸引了一批优秀的地理学者,开展了广泛的地理实地考察,撰写了丰富的地理著作,出版了多种地理读物,培养了众多的地理学人才,为中华人民共和国成立后中国现代地理学的发展奠定了坚实的基础。 相似文献
249.
Z.‐R. Peng 《International journal of geographical information science》2013,27(4):459-481
Current data sharing in the Internet environment is supported using metadata at the file level. This approach has three fundamental shortcomings. First, sharing data from different sources with different semantics, data models, and acquisition methods usually requires data conversion and/or integration like data conflation. This can be tedious and error‐prone. Second, data updated from one source cannot be automatically propagated to other related data or applications. Finally, data sharing at the file level makes it difficult to provide feature‐level data for searching, accessing, and exchanging in real time over the Internet. This paper addresses these three issues by proposing a standards‐based framework for sharing geospatial data in the transportation application domain. The proposed framework uses a standard data model—geospatial data model proposed by the Geospatial One‐Stop initiative to harmonize the semantics and data models without the use of data integration methods. It uses Geography Markup Language (GML) for geospatial data coding and feature relationship, which provides a basis to propagate the data update from one source to related other sources and applications, and to search and extract data at the feature level. The framework uses the Web Feature Service (WFS) to search, access and extract data at the feature level from distributed sources. Finally, the Scalable Vector Graphics (SVG) standard was used for data display on the Web browser. Two transportation network datasets are used in the prototype case study to implement the proposed framework. The prototype allows the user to access and extract data at the feature level on the Web from distributed sources without downloading the full data file. It shows that the proposed standards‐based feature‐level data‐sharing system is capable of sharing data without data conflation, accessing, and exchanging data in real time at the feature level. The prototype also shows that changes in one database can be automatically reflected or propagated in another related database without data downloading. 相似文献
250.
本文从区域开发的角度,对双桥镇的自然与社会要素,农村经济发展现状进行了分析,提出了水土资源优化配置方案:一是强化农田水利的配置工程及合理开采地下水,实行节水农业;二是种养结合,建立有机肥与无机肥相结合的地力培肥体系,建立种养结合的良种繁育体系,培植双桥特色的名、优、特、稀产品。 相似文献