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141.
Hydrocarbons, popular protest and national imaginaries: Ecuador and Bolivia in comparative context 总被引:3,自引:0,他引:3
This paper examines contemporary struggles over hydrocarbon governance in Ecuador and Bolivia. Our comparative analysis illustrates the ways that petro-capitalism, nationalist ideologies, popular movements and place conjoin in the governance of oil and natural gas. In the case of Ecuador, state employees drew on their labor relations and political training to oppose the government’s efforts to privatize the state oil company. In Bolivia, urban popular movements opposed the privatization of the hydrocarbons industry and its domination by foreign firms. In both cases, hydrocarbons struggles involved the production of imaginative geographies of the nation and it hydrocarbon resources, which in turn drew on historical memories of nationhood. Whereas neoliberal political and economic restructuring sought to re-organize national hydrocarbons companies, redraw concessions, and draft new resource extraction laws, hydrocarbon movements aimed to counter these processes by re-centering hydrocarbon governance within a populist vision of the nation-state. In contrast to analyses of resource conflict in the environmental security and resource curse literatures, the cases of Ecuador and Bolivia demonstrate that such struggles cannot be reduced to models of opportunity structure, war profiteering, or resource scarcity (or abundance). Rather, these cases show that political economy and cultural politics are inseparable in the context of resource conflicts, which involve struggles over the meanings of development, citizenship and the nation itself. 相似文献
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植物种群资源竞争与共存的理论模型研究 总被引:1,自引:0,他引:1
自然生态系统不同植物种群之间存在着广泛的竞争,且多种植物种群可以共存,即具有生物多样性。经典的资源竞争模型(莫诺模型)支持生态学上的"竞争排斥原理",不适用于阐释自然生态系统不同植物种群间的竞争与共存。根据植物生态系统的特点,引入植物种群的生长率随着物种个体大小/个体数增加而逐渐趋于饱和的性质,建立自抑制资源竞争模型。该模型与莫诺模型的本质区别在于,物种的临界可利用资源随种群密度增加而上升,从而可以达到不同物种间的平衡。数学分析及数值模拟结果表明,该模型可允许多物种稳定共存(即共存的物种种类数可以多于供给其生长的资源种类数),同时优势物种随资源供给率增加而依次变化。 相似文献
144.
Taneomi Harada 《Natural Resources Research》1993,2(3):247-255
Resource recycling reduces the amount of waste discharged into the global environment. The waste reduction achieved by thorough recycling is substantial. Recycling is thus an inseparable part of global environmental protection.We human beings have used mineral resources since the birth of our species. The quantities and increasingly complex forms in which mineral resources have been used at different times in our prehistory and history serve as indices of civilization's advancement. But on the eve of the 21st century, environmental pollution and global warming stemming from spiraling resource and energy consumption pose serious dilemmas for humanity. The rapidity with which our resource consumption has increased approximates exponential growth.The worsening condition of the earth's environment because of massive resource and energy consumption is the result of activity at many stages of production, from the mining of mineral resources to the manufacture of finished products; the culmination of the process is the disposal of products as waste after their use. As we shall see from examples given in this paper, efforts are being made to solve this problem through recycling; but in many areas the problems remain incompletely solved or unsolved altogether. 相似文献
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河南信阳茶叶资源环境优势及发展 总被引:4,自引:0,他引:4
信阳茶叶是河南省南部大别-桐柏山区的重要经济作物资源之一。该区域地处北亚热带,气候温暖湿润,生态环境复杂多样,植物资源丰富,是河南的鱼米之乡。气候条件独特,利于优质茶叶生长。因此,虽然以信阳毛尖为代表的信阳茶区茶叶面积小,茶叶总产量少,但产品质量上乘,深受茶叶消费者的喜爱,是全国名优绿茶重要产区。依据信阳茶区茶叶资源环境优势,提出进行名优绿色无公害茶产品的开发;组织茶叶产业化发展;加强信阳茶叶生产的标准化研究推广工作和加强对外经济技术联系协作,为河南省信阳茶叶可持续发展提供科学依据。 相似文献
148.
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
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中国金资源预测及金矿远景区划 总被引:3,自引:0,他引:3
本文通过信息量法、方差法、逻辑法及分形理论分别圈定了我国花岗岩型、火山岩型、沉积-变质型岩金矿床的远景区。应用概率法、吉波夫分布法、逆推法、富集系数法、数量化模型Ⅰ法计算了中国金资源总量,并讨论了金成矿区与地质异常的关系。 相似文献