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991.
Sakai Y Shoji R Kim BS Sakoda A Suzuki M 《Environmental monitoring and assessment》2001,70(1-2):57-70
Among bioassays for evaluating various impacts of chemicalson humans and ecosystems, those based on culturedmammalian-cells can best predict acute lethal toxicity to humans. Weexpect them to be employed in the future in environmentalrisk management alongside mutagenicity tests and endocrine-disrupting activity tests. We recently developed adisposable bioassay device that immobilizes humanhepatocarcinoma cells in a small micropipette tip. Thisenables very quick (within 2 h) evaluation of acute lethaltoxicity to humans. For bioassay-based environmentalmanagement, 2 promising approaches have been demonstrated bythe US-EPA: toxicity identification evaluation (TIE) andtoxicity reduction evaluation (TRE). The Japanese Ministryof Environment has been supporting a multi-center validationproject, aimed at assembling a bioassay database. To makefull use of these resources, we present a numerical modelthat describes contribution of individual chemical toobserved toxicity. This will allow the selection of the mosteffective countermeasure to reduce the toxicity. Bioassay-based environmental risk management works retrospectively,whereas impact assessment using substance flow models andtoxicity databases works prospective. We expect that these 2approaches will exchange information, act complementarily,and work effectively in keeping our environment healthy inthe 21st century. 相似文献
992.
P. Gyau-Boakye 《Environment, Development and Sustainability》2001,3(1):17-29
The Akosombo dam was constructed on the Volta river primarily for the generation of hydropower. The resultant Volta lake which was formed between 1962 and 1966 in Ghana will probably long be one of the greatest man-made lakes. It produces 912MW of electricity at its maximum operating capacity. The Akosombo hydroelectric project (HEP) was meant among others to open up Ghana to rapid industrialization and hence modern development. Other positive impacts of the HEP include fishing, farming, transportation and tourism. However, there are equally negative impacts, some of which the project did not envisage and these are felt on the physical, biological and human subsystems within the immediate project environments and places much more distant from them. Recently, there have been declines in the lake levels resulting most probably from inadequate rainfall and/or runoff from the river catchments that feed the lake, and also from the observed rising temperatures. Comparisons of the runoff from two most important tributaries of the Volta (White Volta and Oti) for two time periods of 1951–1970 and 1971–1990 showed reductions in mean streamflows of 23.1% on the White Volta and 32.5% on the Oti. Similarly, a plot of the mean annual temperatures for the upper Volta basin indicated a 1^C rise in temperature from 1945–1993. 相似文献
993.
It is now part of received wisdom that humanitarian assistance in conflict and post-conflict situations may be ineffective or even counterproductive in the absence of an informed understanding of the broader political context in which so-called 'complex political emergencies' (CPEs) occur. Though recognising that specific cases have to be understood in their own terms, this article offers a framework for incorporating political analysis in policy design. It is based on a programme of research on a number of countries in Africa and Asia over the last four years. It argues that the starting-point should be an analysis of crises of authority within contemporary nation-states which convert conflict (a feature of all political systems) into violent conflict; of how such conflict may in turn generate more problems for, or even destroy, the state; of the deep-rooted political, institutional and developmental legacies of political violence; and of the difficulties that complicate the restoration of legitimate and effective systems of governance after the 'termination' of conflict. It then lists a series of questions which such an analysis would need to ask--less in order to provide a comprehensive check-list than to uncover underlying political processes and links. It is hoped these may be used not only to understand the political dynamics of emergencies, but also to identify what kinds of policy action should and should not be given priority by practitioners. 相似文献
994.
995.
论述了博乐市自1992-2006年城市环境噪声状况,对交通噪声、生活噪声、建筑施工噪声及发展趋势进行了分析,并提出必须从城市总体规划的战略高度统筹实施综合整治,有效地控制噪声污染. 相似文献
996.
指出循环经济背景下我国环境信息分布中的致命问题--环境信息的不对称分布,并指出不对称的表现,而后分析了环境信息对称对于循环经济的影响,在此基础上提出解决环境信息不对称的对策--发展环境信息服务业,并初步探讨了发展环境信息服务业的模式和步骤. 相似文献
997.
998.
刘少宁 《中国环境管理干部学院学报》2007,17(1):4-6
最近美国离境外包经济发展很快,并引发继第一次产业革命(即工业革命)和第二次产业革命(即服务业超过制造业)之后的第三次产业革命,进而美国大批制造业向国外转移。这对我国承接制造业的产业转移是重大机遇,但同时也会遇到污染、能源转移的问题。建议我国抓住机遇,保持和发挥人力资源优势,迅速发展制造业,同时积极应对环境影响,分类管理,严格执法。 相似文献
999.
1000.