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991.
防洪减灾观念的理论进展--灾害双重属性概念及其科学哲学基础 总被引:4,自引:3,他引:4
提出灾害的双重属性概念,是国际减灾十年活动中的重要理论进展之一,已被国家防洪减灾主管部门所采纳,被认为是防洪减灾方针转变的理论基础.作者总结了多年来的研究心得,论述了灾害双重属性概念的实质,以及它和工程与非工程相结合的减灾措施之异同.论述了这个科学概念系来源于我国传统治水理念和西方现代防洪减灾思想,并阐述了这一概念的科学和哲学基础. 相似文献
992.
中国自然灾害应急管理研究进展与对策 总被引:20,自引:2,他引:20
从中国自然灾害应急管理的现状出发,系统分析了自然灾害应急管理领域的研究进展,指出了中国自然灾害应急管理在理论和实践方面存在的问题.在此基础上,提出了中国自然灾害应急管理框架,认为建立适合中国国情的自然灾害应急管理体制是提高中国自然灾害应急管理的基础;应急预案的制定和实施是规范灾害应急管理,提高灾害紧急救援能力的关键措施;灾害信息快速准确的获取和评估是灾害应急管理的有效保障;建立实际可用的应急管理系统是提高灾害应急管理水平和工作效率的根本出路. 相似文献
993.
伊犁地区林牧区生态系统的保水功能受到畜牧业生产活动的影响已明显下降,尤其是山地天然林资源的生态总体质量和生态功能都同步处于下降趋势。伊犁地区的生态建设重点应放在山地天然林分布区。保护和大力发展山地天然林资源是伊犁地区生态产业发展的核心内容。大力营造山地人工林,是目前条件下保护和发展山地森林资源的最有效手段。每年营造山地人工林不少于0 3×104hm2,才能够基本保持山地森林生态系统在资源总量和生态效能上的稳定,才能够基本维持伊犁地区以往良好的生态形象。建议自治区人民政府继续启动实施天山、阿尔泰山百万亩山林再造工程。 相似文献
994.
Vonne Lund Sven Hemlin James White 《Journal of Agricultural and Environmental Ethics》2004,17(2):157-179
A questionnaire study was performed among Swedish organic livestock farmers to determine their view of animal welfare and other ethical issues in animal production. The questionnaire was sent to 56.5% of the target group and the response rate was 75.6%. A principal components analysis (exploratory factor analysis) was performed to get a more manageable data set. A matrix of intercorrelations between all pairs of factors was computed. The factors were then entered into a series of multiple regression models to explain five dependent variables. Respondents were well educated and had long experience of farming. 81% were full-time farmers. They generally had a very positive attitude towards organic animal husbandry. They considered allowing animals their natural behavior a central aim, which is in accordance with organic philosophy. Farmers tended to be less approving of concepts like animal rights, dignity, and intrinsic value. When analyzing correlations between the factors, two groups of farmers emerged that were only partially correlated, representing different attitudes and behavioral dispositions. These may be interpreted as two subpopulations of organic livestock farmers in Sweden: those who saw organic farming as a lifestyle (``pioneer attitude') and entrepreneurs, who considered making money and new challenges more important. Their view of animal welfare differed. While the pioneers considered natural behavior a key issue, this was less important to the entrepreneurs, who also had a more approving attitude towards invasive operations such as castration and were more critical of the organic standards. 相似文献
995.
Sustainability is a concept that has been widely embraced both politically and intellectually but has not been addressed in terms of practical application. In most resource sectors, the features of a sustainable future remain unclear and there are few examples that give practical expression to sustainability. This is especially true in the case of water resources management which has been conspicuous in its absence from the majority of the literature. This paper attempts to address this deficiency on two counts. First, it provides a discussion of sustainability and the application of the concept to the management of water resources. Second, the paper illustrates how the concept can be utilized for the management and planning of urban stormwater. The paper concludes by offering research opportunities to investigate the feasibility of adopting natural channel design and artificial wetlands for sustainable stormwater management. 相似文献
996.
本文根据福建省历史上自然灾害事例概括出洪涝、干旱、地震、水土流失、冰雹、寒害等自然灾害特点。并从地理位置、环流因素、地形、地质构造、人为因素等方面分析了福建自然灾害形成的背景原因。最后针对福建省自然灾害特点提出了减灾建议。 相似文献
997.
特、稀、濒危植物的数量与特征研究是自然资源保护的主要环节。本文根据它们的保护等级、分布局限性、稀有值、物种吸引力、保护指数以及理论研究值6个标准,对江苏15种国家级保护植物、24种省级保护植物的生态学意义作出初步评价。 相似文献
998.
999.
D. W. Bacon O. T. Coomes A. A. Marsan N. Rowlands 《Journal of the American Water Resources Association》1986,22(1):29-38
ABSTRACT: A comparative study of the concentration of asbestos fibers in drinking water supplies of southeastern Quebec was undertaken to assess the relative contributions of fibers by asbestos-bearing railway ballast and naturally occurring asbestos deposits. Water samples were taken from areas where one or the other potential sources or neither potential source was present. In addition, rainwater samples were taken to assess the importance of atmospheric contributions. The sampling design accounted for potential variations in fiber counts due to the season, location and analytical procedures. Fiber concentrations were estimated from counts made on a JEOL 100CX scanning transmission electron microscope and statistically compared among areas. These levels were then compared with levels found in other areas of Canada and the United States. The results indicate that the rail ballast could be contributing statistically (albeit marginally) significant quantities of fibers to water supplies during the summer but not in the spring. Estimated concentrations in water supplies ranged between 1.7 × 106fibers/liter and 147.8 × 106fibers/liter. Fiber levels in samples taken during the spring were significantly higher and more variable than those taken during the summer. The presence of fibers in rainwater samples at concentrations of 1.9 × 106fibers/liter, 18.3 × 106fibers/liter and 23.7 × 106fibers/liter suggests that atmospheric transport may play an important role in contributing fibers to regional systems. Fiber levels found in these systems are not unique when compared to levels observed elsewhere in North America. 相似文献
1000.
层次分析法在自然保护区生态评价中的应用 总被引:2,自引:0,他引:2
对自然保护区的多样性、代表性、稀有性等诸项指标进行分析,以太白山自然保护区为例,运用层次分析法针对自然保护区综合评价之一的生态评价建立层次结构模型,构造各项评价指标的判断矩阵并计算权重,从而得出生态现状评价结果. 相似文献