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11.
陈星 《地球信息科学学报》2003,5(4):74-76
本文阐述了以地球表层为研究对象的地理学在信息革命的巨大影响下 ,将面临的 3大问题 :(1 )可持续发展--弄清地球表层巨系统的驱动力、运行机制、调控方法等可持续发展问题 ;(2 )经济全球化--各种经济、社会要素在大尺度空间内流动与融合 ,研究其地域分异规律和人地系统问题 ;(3)人类行为与区域响应--信息分布、交流的新格局对人类社会行为的影响和与其相关的自然、人文地理问题。认为地理学的空间观、时间观、尺度观、变化观、综合观、表达观及其方法论为地理学解决上述问题提供了可能性。指出了在信息社会里解读数字空间将遇到的 4个转变 :研究对象的转变 ,时空观的转变 ,研究手段的转变 ,研究方法的转变。提出了通过对数字空间的解读 ,实现对地球表层的全面深入的研究 ,同时也使地理学的定量研究方法走向成熟。 相似文献
12.
地下贯通工程测量方案的优化理论和方法 总被引:2,自引:0,他引:2
地下贯通工程的控制测量导线多为加测陀累方位角的导线,本文讨论了贯通工程导线加测陀螺边的个数,位置,以及提高其可靠性,经济性的有关问题。 相似文献
13.
Wild mushrooms are recognized as important non-wood forest products in mountainous ecosystems, but their real potential for generating rural economies has not been fully evaluated due to the difficulties in obtaining reliable productivity data, minimizing their true potential as contributor to rural economies. Mushroom yield models based on large data series from Pinus forest ecosystems in the region of Catalonia(Spain), combined with data from the Spanish National Forest Inventory allow us to estimate the potential mushroom productivity by forest ecosystems. The results of 24,500 tons/yr of mushrooms of which 16,300 tons are classified as edible and 7,900 tons are commonly marketed demonstrate the importance of mushroom productions in Catalonian pine forests, mostly located in mountainous areas where the development of agricultural activities is limited. Economic mushroom value is estimated at 48 million € for the edible mushroom and 32 million € for those corresponding to marketable yields, confirming the potential of this non-wood forest product. These production results and corresponding economic values provide a basis for the incorporation of wild mushrooms as significant non-wood forest products in the development of forest policies in mountainous areas. 相似文献
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16.
《Geoforum》2017
Agri-environmental policies and planning influence agricultural landscape management, and thus the capacity to deliver landscape services and to contribute to rural viability. Numerous models and frameworks have been developed to improve comprehension of the mechanisms and interrelationships between policies, landscape and socio-economic values and benefits. As social-ecological systems, landscapes are closely depending from the socio-institutional and territorial context of the specific rural locality. The paper proposes an enhanced framework for assessing these mechanisms by acknowledging the critical role of the regional macro-environment. A literature review and the revisiting of evidence from eight European case studies are applied to establish a comprehensive understanding and exemplification of the links between the policies, landscape, ecosystem services and value flows. Results highlight the need for integrative, inter- and transdisciplinary research approaches. Efficient landscape policies require enhanced regional embeddedness and targeting, acknowledgement of user demands and the capability of regional community and governance structures for policy implementation and natural capital valorisation. 相似文献
17.
《Geoforum》2016
This paper examines economic upgrading in the Canarium indicum (Canarium) nut industry in Vanuatu, the Solomon Islands and Papua New Guinea. Canarium is a tree that is indigenous to Melanesia, and has been the subject of several commercialisation attempts since 1988. The paper assesses the outcomes to various actors in the Canarium supply chain from attempts to upgrade industry products and processes by: (1) increasing the available resource in suitable locations; (2) improving nut products and processing techniques; (3) increasing actors’ knowledge and supply chain coordination; and (4) establishing product standards. A two-phase data generation process was implemented. Document analysis and participant observations of industry workshops initiated a set of four economic upgrading interventions that were adaptively implemented. A second stage of workshops and 76 interviews enabled outcomes to be assessed at the project’s end. Findings suggest that a small number of urban-based entrepreneurs benefit and subsequently are lead actors in industry development, but at the expense of benefits being distributed to a larger, more spatially disparate group of smallholder and small commercial growers. These economic upgrading outcomes are circumscribed by core-periphery relations in Pacific small island states and the scale of industry in each country. Thus, spatial inequalities are reproduced through the emerging Canarium industries. We argue that different routes to industry development are required in each country. Development initiatives that capitalise on the benefits of micro-enterprise clusters, joint action and regional institutional arrangements are proposed to overcome the impediments imposed by the particular geographies of Pacific island states. 相似文献
18.
Elaine Stratford 《Geoforum》2006,37(2):273-286
Baldacchino [Baldacchino, G., 2002. Jurisdictional self-reliance for small island territories: considering the partition of Cyprus, The Round Table, 365, 349-360] has argued that the ‘troika’ of smallness, insularity and peripherality may incline island peoples (rather more than mainlanders?) to question the effects of economic globalization and be especially disposed to innovative approaches to development. He views jurisdictional capacity as integral to that task. Much of the literature on such issues relates to island nations, but this work focuses on Australia’s smallest and only island state of Tasmania, and thus on a sub-national jurisdiction. In what follows I explore the effects of an attempt to enrol Tasmanians in the creation and stabilization of a ‘2020 vision’ meant to be global in its reach, to focus on the particular strengths of the island state, and be innovative in advancing sustainable development. Known as Tasmania Together, the 20-year strategic vision outlines diverse economic, social and environmental goals assembled over two years via widespread consultations with the island’s communities of place and interest. For a time Tasmania Together generated significant debate about what it means to be an island people, and whether and to what extent Tasmanians’ future will be secured through economic globalization or localized endeavours premised on sustainability principles. Important to Tasmanians as well as to island studies, these rhetorics of social and spatial engagement also have salience beyond the borders of the island state, highlighting larger questions about the technologies of governmentality, agency and the performance of identity. 相似文献
19.
湖南大坊金银矿氧化带特征及工业意义 总被引:1,自引:0,他引:1
湖南大坊金银矿位于耒阳—临武南北向构造带中段,控矿层位为石炭系中上统壶天群和下统梓门桥组白云岩。矿体受北西和北东向组扭裂面的控制,产于花岗闪长斑岩内外接触带。氧化带的有用组分为金和银,已圈定矿体7个,其平均品位Au 2.68 g/t,Ag26.20g/t。金的粒度以中—细粒为主,氰化浸出率在91%以上,银经槽浸回收率仅20-30%。鉴于金浸出率高,矿体埋藏浅。开采技术条件简单,交通方便等特点,值得开发利用。 相似文献
20.
Geography (or geographers) and earth system science 总被引:1,自引:0,他引:1
Ron Johnston 《Geoforum》2006,37(1):7-11
A response to Pitman’s recent arguments regarding a perceived invasion of geographers’ territory within the academic division of labour by earth system science. Geography is not the grand synthesiser, the only discipline which can explain the big picture, and arrogant claims that it is are counter-productive, both within and outwith the discipline. Geographers should just get on with what they are doing—well. 相似文献