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71.
This research aims to establish the risks of hurnan exposure to modeling approach. The study site was located on the River Nura 1990s, an acetaldehyde production plant located in the industrial high environmental mercury levels, based on a quantitative risk in central Kazakhstan. From the 1950s until its closure in the mid city of Temirtau released mercury-containing wastewater into the river. River sediments are highly contaminated with mercury up to a distance of 25 km and beyond. In addition, a local power station released an estimated 6 million tonnes of fly-ash into the water and the mercury has become quite tightly associated with the ash deposits. River water, fish and agricultural land in the floodplain are also contaminated with mercury, yet the risks posed to the local population have not been evaluated to date. In June and July 2005, we took samples of soil, interior and exterior dust, drinking water, and food from individual households, communal areas and markets. Additionally, water and sediment samples and fish were taken from the river. Interviews were conducted with householders to establish their age and body weight, general living conditions and sources of irrigation and drinking water. A food frequency questionnaire (FFQ) was designed to investigate the frequencies of consumption of several common regional food items, including fish from the fiver and/or local market. Human hair samples were also collected to estimate the mercury bioburden and to enable the validity of the modeling approach to be established. The paper expands on the main pathways of contamination and looks at linkages between exposure pathways and mercury concentrations found in human hair. Uncertainties inherent in risk analysis as well as their influence on the relative importance of different exposure routes are also discussed.  相似文献   
72.
In this paper, a multi-method approach for the assessment of the stability of natural slopes and landslide hazard mapping applied to the Dakar coastal region is presented. This approach is based on the effective combination of geotechnical field and laboratory works, of GIS, and of mechanical (deterministic and numerical) stability analysis. By using this approach, valuable results were gained regarding instability factors, landslide kinematics, simulation of slope failure and coastal erosion. This led to a thorough assessment and strong reduction in the subjectivity of the slope stability and hazard assessment and to the development of an objective landslide danger map of the SW coast of Dakar. Analysis of the results shows that the slides were influenced by the geotechnical properties of the soil, the weathering, the hydrogeological situation, and the erosion by waves. The landslide susceptibility assessment based on this methodological approach has allowed for an appropriate and adequate consideration of the multiple factors affecting the stability and the optimization of planning and investment for land development in the city.  相似文献   
73.
Within the framework of recent research projects, basic tools for GIS-based seismic risk assessment technologies were developed and applied to the building stock and regional particularities of German earthquake regions. Two study areas are investigated, being comparable by the level of seismic hazard and the hazard-consistent scenario events (related to mean return periods of 475, 2475 and 10000 years). Significant differences exist with respect to the number of inhabitants, the grade and extent of urbanisation, the quality and quantity of building inventory: the case study of Schmölln in Eastern Thuringia seems to be representative for the majority of smaller towns in Germany, the case study of Cologne (Köln) stands for larger cities. Due to the similarities of hazard and scenario intensities, the considerable differences do not only require proper decisions concerning the appropriate methods and acceptable efforts, they enable conclusions about future research strategies and needs for disaster reduction management. Not least important, results can sharpen the focus of public interest. Seismic risk maps are prepared for different scenario intensities recognising the scatter and uncertainties of site-dependent ground motion and also of the applied vulnerability functions. The paper illustrates the impact of model assumptions and the step-wise refinements of input variables like site conditions, building stock or vulnerability functions on the distribution of expected building damage within the study areas. Furthermore, and in contrast to common research strategies, results support the conclusion that in the case of stronger earthquakes the damage will be of higher concentration within smaller cities like Schmölln due to the site-amplification potential and/or the increased vulnerability of the building stock. The extent of damage will be pronounced by the large number of masonry buildings for which lower vulnerability classes have to be assigned. Due to the effect of deep sedimentary layers and the composition of building types, the urban centre of Cologne will be less affected by an earthquake of comparable intensity.  相似文献   
74.
利用空间主成分分析方法,选取降水、坡度、植被、土地利用、土壤类型、人口、高程等作为评价指标,建立空间主成分评价模型Pi=0.78X1+0.06X2+0.05X3+0.04X4,将研究区分为无险型、轻险型、危险型、强险型和极险型五种类型,较为准确地得到了危险度综合评价结果。因此,空间主成分分析模型,在土壤侵蚀危险程度评价方面的应用较为成功,是一种科学有效的研究方法。  相似文献   
75.
认为有必要在基于碳汇的土地利用和当地可持续发展之间建立一种更加明确的联系.依托一个中国-加拿大合作项目,以中国贵州省黎平县为例,阐述了一种将森林碳汇、森林资源管理以及如何促进当地可持续发展联系起来的综合评估方法,并且着重介绍了能帮助资源管理和规划部门实施这种综合评估的土地利用决策支持工具(LUDST) .  相似文献   
76.
Based on the high temperature data of June to August in 1961-2000 in North China, the high temperature weather processes are investigated, and a more complete data set for severe high temperature processes is created. The climatic characteristics of adverse high temperature weather in Beijing, Tianjin, Shijiazhuang, Jinan and Taiyuan are analyzed respectively. The major features of the East-Asia Subtropical High and Transformed Continental High are discussed. The outcomes indicate that the influence of both East Asia Subtropical High and Transformed Continental High on these weather events varies, by a larger margin, from one city to another over North China and they are also closely related to the relative humidity. It is found that the behaviours of East-Asia Subtropical High and Transformed Continental High are the major important systems that give rise to the summer high temperature weather over the region. Based on these findings, the 5-day, 10-day and monthly assessment models for such high impact events have been developed. The assessment outcomes prove to be useful in assessing severe high-temperature events in major cities of North China.  相似文献   
77.
认为有必要在基于碳汇的土地利用和当地可持续发展之间建立一种更加明确的联系.依托一个中国-加拿大合作项目,以中国贵州省黎平县为例,阐述了一种将森林碳汇、森林资源管理以及如何促进当地可持续发展联系起来的综合评估方法,并且着重介绍了能帮助资源管理和规划部门实施这种综合评估的土地利用决策支持工具(LUDST).  相似文献   
78.
推进煤矸石资源化利用的对策建议   总被引:10,自引:0,他引:10  
煤矸石是我国排放量和堆存量最大的工业固体废弃物之一,但又是可以利用的资源,只要加以资源化利用,就能会变废为宝。在研究我国煤矸石综合利用现状的基础上,指出了煤矸石综合利用中存在的主要问题,从制定规划、完善经济政策、加强法制建设等方面提出了加快推进煤矸石资源化利用的建议。  相似文献   
79.
油页岩综合利用对周围环境的影响——以抚顺矿区为例   总被引:3,自引:0,他引:3  
世界能源日益减少的局面为油页岩的开发应用带来广阔的前景,但油页岩工业所带来的环境影响亦不容忽视。以抚顺油页岩为例,从油页岩综合利用和油页岩工业对环境的影响等方面系统讨论了在我国发展油页岩工业时,如何本着节约能源、保护环境、实现可持续发展的观念,利用现有先进技术,科学发展油页岩工业,降低生产过程中的固、液、气污染物对环境的危害。  相似文献   
80.
MODIS数据在广西生态环境监测及评价中的应用方法   总被引:8,自引:0,他引:8  
利用MODIS数据广西遥感影像,用监督分类法做出了地物覆盖分类图,用主成分分析法做出了土壤侵蚀强度图和生态环境质量综合评价指数图。  相似文献   
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