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91.
城市地震防御能力评价和防御水准问题 总被引:8,自引:1,他引:8
本文研究了下列两个问题:(1)城市防御地震能力的评价标准和评价方法;(2)考虑了经济投入和人身安全,确定新建建筑设防水准的合理方法。 相似文献
92.
Cho ST Tsai SH Ravindran A Selvam A Yang SS 《Environmental geochemistry and health》2008,30(3):255-272
To investigate the seasonal variations of microbial ecology in grassland of Tatachia forest, soil properties, microbial populations,
microbial biomass, and 16S rDNA clone library analysis were determined. The soil had temperatures 6.6–18.4°C, pH 3.6–5.1,
total organic carbon 1.11–10.68%, total nitrogen 0.18–0.78%, and C/N ratios 3.46–20.55. Each gram of dry soil contained bacteria,
actinomycetes, fungi, cellulolytic, phosphate-solubilizing microbes, and nitrogen-fixing microbes 4.54 × 104 to 3.79 × 107, 3.43 × 102 to 2.17 × 105, 5.74 × 103 to 3.76 × 106, 1.97 × 103 to 1.34 × 106, 8.49 × 102 to 5.59 × 105, and 3.86 × 102 to 3.75 × 105 CFU, respectively. Each gram of soil contained 117–2,482 μg of microbial biomass carbon, 23–216 μg of microbial biomass nitrogen
and 9–29 μg of DNA. The microbial populations, microbial biomass, and DNA decreased stepwise with the depth of soil, and they
had low values in winter seasons. The microbial populations, microbial biomass carbon, microbial biomass nitrogen, and DNA
at the BW2 horizon were 8.42–17.84, 19.26–64.40, 16.84–61.11, and 31.03–46.26% of those at the O horizon, respectively. When
analyzing 16S rDNA library, members of Proteobacteria, Acidobacteria, Actinobacteria, Bacteroidetes, Chloroflexi, Firmicutes,
candidate division TM1, candidate division TM7, Gammatimonadetes, and Verrucomicrobia were identified. Members of Proteobacteria
(44.4%) and Acidobacteria (33.3%) dominated the clone libraries. Within the phylum Proteobacteria, α-, β-, and γ-Proteobacteria
were most numerous, followed by δ-Proteobacteria. 相似文献
93.
分析了压力容器事故的主要原因 ,介绍了劳动安全监察制度 ,研究了该制度对减少压力容器事故所起的作用 ,为预防压力容器事故 ,对劳动安全监察制度的发展 ,提出了自己的见解与看法。 相似文献
94.
Coupling a 3D patch model and a rockfall module to assess rockfall protection in mountain forests 总被引:1,自引:0,他引:1
Woltjer M Rammer W Brauner M Seidl R Mohren GM Lexer MJ 《Journal of environmental management》2008,87(3):373-388
Many forests in the Alps are acknowledged for protecting objects, such as (rail) roads, against rockfall. However, there is a lack of knowledge on efficient silvicultural strategies and interventions to maintain these forests at optimal protection level. Therefore, assessment tools are required that quantify the rockfall protection effect of forest stands over time, and thereby provide the ability to evaluate the necessity and effect of management interventions. This paper introduces such a tool that consists of a 3D rockfall module embedded in the patch based forest simulator PICUS. The latter is extended for this study with a new regeneration module. In a series of experiments the new combined simulation tool is evaluated with regard to parameter sensitivity, model intercomparison experiments with recently proposed algorithms from the literature, and the ability to respond realistically to different management regimes in rockfall protection forests. Results confirm the potential of the new tool for realistic simulation of rockfall activity in heterogeneous mountain forests, but point at the urgent need to improve the knowledge base on the interaction of understory and rockfall activity. Further work will focus on model validation against empirical rockfall data, and include reduced tree vitality due to damage from boulder collisions as well as the explicit consideration of downed dead wood. 相似文献
95.
The numerous formulated products which are introduced to the market consist of chemical ingredients that may cause various safety and health hazards to the consumers. Therefore, it is extremely important to practice a systematic methodology to formulate products with acceptable safety and health performances. This work presents an index-based methodology to assess the safety and health hazards of the ingredients during the early formulation stage of product design. Hence, new inherent safety and health sub-indexes are introduced to improve the current safety and health hazards that are needed in formulated product design. The inherent safety and health sub-indexes are assigned with scores based on the degree of potential hazards. A higher score indicates a higher safety risk or severe health effect, and vice versa. The proposed methodology will greatly assist the users to identify the adverse safety and health effects caused by the ingredients. Hence, it is pivotal to eliminate or reduce the safety and health impacts from product usage. A case study on common ingredients used in the formulation of paint is presented on this study to describe the proposed method. 相似文献
96.
An ecological economics approach to the management of a multi-purpose coastal wetland 总被引:1,自引:1,他引:0
R. K. Turner I. J. Bateman S. Georgiou A. Jones I. H. Langford N. G. N. Matias L. Subramanian 《Regional Environmental Change》2004,4(2-3):86-99
Three interrelated management problems—eutrophication of multiple use shallow lakes, sea level rise and flood risk mitigation and tourism pressures—are analysed in the context of an internationally important wetland area, the Norfolk and Suffolk Broads in the UK. The ecological-economic research findings presented should provide essential information to underpin the regulatory and management process in this internationally important conservation area. The relevant authority somehow has to integrate the maintenance of public navigation rights, nature conservation, and tourism promotion in a highly dynamic ecosystems setting. Because of the stakeholder conflicts, potential and actual, a more inclusionary decision-making procedure is required, and is currently being implemented. 相似文献
97.
D. Jeffrey 《Journal of Environmental Planning and Management》1990,33(2):108-117
The growing political and public profile of tourism has led to the need for local estimates of its economic impact and importance, especially the number of jobs involved. In particular there is a need to produce spatially and temporally disaggregated estimates of visitor numbers, visitor spending and tourism‐related employment. This paper outlines and uses an indirect non‐survey method for estimating the tourism‐related workforce in local areas proposed by Roger Vaughan. The method is applied to recently published 1987 Census of Employment data for Yorkshire and Humberside. 相似文献
98.
The threat of man-induced global change on the nations of the South Asian seas region varies from place to place because of
differences in exposure to monsoons and stoms, differences in local tectonics and subsidence, and variations in air and sea
climates. Because several nations are involved, some having subsistence budgets, and given the cost of deriving independently
a comprehensive response to global change, the similarities and differences between national settings must be identified soon.
These comparisons will form the basis for local response strategies: the similarities provide a basis for responses similar
to that of other nations and the differences provide for local adaptation. That climate change on the South Asian coastal
region will have an impact is certain: its economics, environment, and coastal land uses are dominated to a certain extent
by this marine influence. The extent of these impacts, however, is uncertain. Accompanying global change will be changes in
sea level, differences in storm climate, and altered precipitation patterns; science cannot define today what pattern these
changes will take. Because global change is inevitable—although its magnitude, timing, and geographic distribution are unknown—the
South Asian seas region should begin the appropriate research and planning studies to set forth a reasoned response to global
change, for implementation when scientific evidence for global change is more quantitative. 相似文献
99.
自然保护区生态旅游开发及保护规划探讨——以武夷山自然保护区为例 总被引:3,自引:0,他引:3
对自然保护区生态旅游开发意义和特点进行阐述,并以武夷山自然保护区为例,探讨如何制订自然保护区生态旅游保护规划,提出管理监控的内容和方法。 相似文献
100.
近年来由于地下水补给区的盲目开发和市区地下水超采,素以“泉城”闻名的济南市泉水持续断流,加强泉域地下水补给区的生态环境保护是解决这一问题的关键,在详细研究区域地质水文条件的基础上借助地理信息系统,将补给区划分为三级保护区,即核心保护区,直接补给区和间接补给区,并应用环境承载力分析的理论方法,确定出保护区23个汇水区的环境承载人口,本文对泉域地下水补给区总体发展战略和具体保护规划的制定具有重要的意义。 相似文献