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71.
72.
频率域电磁测深中的记录规则 总被引:1,自引:0,他引:1
首先讨论了频率域电磁测深中的记录规则,然后利用三维数值模拟结果作了具体分析。认为,在不考虑微弱的阴影效应时,将测深点作为频测记录点更为合理。野外试验对比说明了同样的结论。 相似文献
74.
湖北宜昌石板溪金矿区断层空间结构及其控矿规律研究 总被引:1,自引:0,他引:1
断层空间结构包括变形结构和几何结构两部分。本文在解析石板溪金矿区主要断层变形结构和几何结构的基础上,探讨了其空间结构模式和控矿规律。 相似文献
75.
Pastoral production around artificial watering points in semi-arid environments affects the density and composition of plant communities. In the Kalahari desert of southwestern Africa, bush encroachment is often regarded as the major form of land degradation resulting from pastoral production around watering points. We investigated the OvaHerero pastoralists’ perceptions of the extent of vegetation change since the establishment of artificial watering points in the northern Kalahari desert of Namibia, and related this to ecological data on vegetation change. We determined the utility of woody vegetation to pastoralists’ livelihoods in terms of provision of construction material, fuel wood and browse. We quantified local knowledge of cattle browse consumption and correlated this with field data. We also assessed the purposes for which major livestock types were used. Our results showed that: (1) pastoral knowledge of bush encroachment and browse consumption was consistent with concurrently collected field data, (2) the current level of bush encroachment was perceived to be beneficial for pastoral production, and (3) cattle played an important role in the production of milk and milk by-products for domestic use, and served as a source of cash income, while sheep and goats were primarily kept for meat consumption. This result contrasts with historical studies that mainly portray cattle as a symbol of social status among OvaHerero pastoralists. 相似文献
76.
Elana Wilson 《Area》2007,39(3):323-330
In this article, I trace the efforts of a development team working to promote a Canadian approach to natural resources management in the Russian North. These development workers used two communication strategies related to time and history to render Canadian knowledge mobile and applicable to a new location: (1) imagining today's Russian North as equivalent to the Canadian northern past and (2) reframing and idealising the Canadian past and present to make the governance export less discursively 'messy' for an outside audience. The relative failure of these communicative strategies points to the need for richer dialogue in efforts to move knowledge cross-culturally. 相似文献
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Local knowledge has played an active role in the lives of rural communities in virtually every part of the world. In Jamaica, traditional cropping systems based on local informal knowledge have been practiced since the days of slavery and play a vital role in meeting food security. Yet, some negative attitudes remain about the legitimacy and relevance of small-scale farmers' local and traditional knowledge. This paper discusses some conceptual and empirical issues related to the application of local knowledge among small-scale food farmers in central Jamaica. The paper argues that contextually speaking, local and traditional knowledge is valuable, adaptable and necessary in coping with risk and uncertainty in a changing world, while cautioning against a misguided notion of traditional knowledge as a panacea to all the ills of local agriculture. 相似文献
79.
Tariq Jazeel 《Singapore journal of tropical geography》2007,28(3):287-299
This paper responds to recent postcolonial geographical scholarship that sets forth transformative agendas in order to create more cosmopolitan theoretical projects within the discipline. For many geographers the challenges they face are located within not only their own disciplinary parameters, but also those of other specific research communities within which their work situates them. By bringing geography and area studies into productive conversation, this paper explores the tensions between negotiating one's academic voice, position and responsibility within geography as well as within a specific area studies community. More specifically, as a UK-based geographer I reflect on some of my own fairly unremarkable, yet extremely awkward, encounters during the course of scholarly praxis in Sri Lanka in order to raise questions over the spatialities of responsibility and political engagement in such academic praxis. I seek to theorize the chasms that open in such awkward encounters between notionally situated 'local' and 'foreign' scholars respectively and, in particular, develop ways of engaging and reorienting those chasms in ways that might enable the production of theoretically rich, yet richly contextualized postcolonial knowledges committed to the site of one's scholarly praxis – not just to the advancement of a more cosmopolitan theoretical project within geography. 相似文献
80.
文章从如何做好防震减灾科普知识的宣传与培训教育工作,提高群众在地震发生时的自救、互救能力和抢险救灾能力等方面进行了论述,并提出了相应的想法和建议。对切实提高社会公众防灾减灾的能力、普及防震减灾知识有一定的参考价值。 相似文献