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891.
Udo E. Simonis 《The Environmentalist》2002,22(1):29-42
With the beginning of the new millennium, the longstanding need for reform of the United Nations system has gained new momentum. Efficiency gains and better coordination are desirable, though not sufficient to bring about improvement in international relations. There is need, therefore, to look for institutional innovations that would upgrade the pressing tasks of environmental and development policy in the eyes of national governments, international organizations, and non-governmental organizations, improve the institutional setting for the negotiation and implementation of new agreements and action programs, and strengthen the action capacity of the developing countries on these matters. The present article points to and elaborates on the need for a World Environment and Development Organization within the United Nations system, and outlines the shape it might be given. 相似文献
892.
Akim M. Rahman 《The Environmentalist》2002,22(4):387-392
The recent resolution of the seventh Conference of the Parties to the Climate Convention (COP7) indicates that if a country is required to comply with the pollution limit, part of the required reduction in levels of emission will have to be achieved domestically. With this status quo, policy practitioners may opt to design emission level standards along with the provision of allowing access to the international permit market that may facilitate carbon offset crediting to the country. In policy formulation cognate to electricity generation through coal combustion, it is suggested that end-users will pay emission compliance costs in terms of the price of electricity usage and the companies will offer a rebate on reduction to those who curtail the level of usage of electricity. Under the scheme proposed, the generating company(s) will face the consequences if it fails to comply to domestic emission standards. In practice, the proposed method can ensure Pareto efficiency and exhibit Pareto improvement in two-party cases where both parties have joint interest in profit maximization, but they may have dichotomy in their activities. In dealing with domestic greenhouse gas issues, the proposal becomes appealing to parties for reducing the level of emissions. Moreover, it may produce a greater degree of abatement of CO2 emissions over the levels of abatement resulting from policies of consumer or producer liability assignments. 相似文献
893.
The concept of a recycling system aiming at the recovery of resources from manufactured articles is proposed. The system integrates electronic labels for product identification and internet for global data exchange. A prototype for the recycling of electric motors has been developed, which implements a condition-based recycling decision system to automatically select the environmentally and economically appropriate recycling strategy, thereby opening a potential market for second-hand motors and creating a profitable recycling process itself. The project has been designed to evaluate the feasibility of electronic identification applied on a large number of motors and to validate the system in real field conditions. 相似文献
894.
The extraordinary events of the major,sudden stratospheric warming,the diminutive antarctic ozone hole,and its split in 2002 总被引:1,自引:0,他引:1
Varotsos C 《Environmental science and pollution research international》2004,11(6):405-411
GOAL, SCOPE AND BACKGROUND: Great interest in the unprecedented events of the major, sudden stratospheric warming and the ozone hole split over Antarctica in September 25, 2002 motivates a necessity to analyze the current understanding on the dynamics, chemistry and climate impacts that are associated with both events. METHODS: Significant progress in the analysis of the observational data obtained, as well as successful development and application of dynamical modeling, which have been achieved very recently, create a basis for the first survey on the role of the major, sudden stratospheric warming observed in the southern hemisphere and its relationship to the diminutive Antarctic ozone hole and its break up into two parts. RESULTS AND DISCUSSION: Special attention has been paid to assessments of the causes of the major warming event and the future expectations concerning the stratospheric ozone depletion effect. Among the principal results is the fact that, as the polar vortex elongated, it became hydrodynamically unstable, and this insta-, bility affected the upper troposphere and stratosphere. During the major, sudden stratospheric warming, the middle stratospheric vortex split into two pieces; one piece rapidly mixed with extra vortex air, while the other returned to the pole as a much weaker and smaller vortex. The polar night jet was considerably weaker than normal, and was displaced more poleward than has been observed in previous winters, resulting from a series of wave events (propagated from the troposphere) that took place over the course of the winter. Finally, the relative ozone decrease (increase) in the eastern Antarctic is tightly associated with westerly (easterly) zonal wind anomalies near the southern tip of South America, and the unusual behavior of the ozone hole in 2002 therefore appears to be caused by great easterlies in this region. CONCLUSIONS: The main conclusion is that the southern polar vortex and the diminutive ozone hole split into two parts in September 2002, due to the prevalence of very strong planetary waves, led to the appearance of a major, sudden stratospheric warming. Although there is evidence that sea surface temperature anomalies contributed to the excitation of the quite strong planetary waves over Antarctica in 2002, there is not yet a widely approved mechanism supporting that. RECOMMENDATIONS AND OUTLOOK:The appearance of the near-record size of the 2003 ozone hole confirmed that the 'no-ozone-hole' episode observed in the year 2002 does not denote a recovery of the ozone layer. Despite the current successful attempts to get a sufficient understanding for the genesis of both extraordinary events, more observations and further modeling efforts are necessary to more reliably assess the contribution of various dynamic mechanisms to the recently observed tropo-stratospheric surprises. 相似文献
895.
Geographic information systems (GIS), global positioning systems and remote sensing have been increasingly used in public health settings since the 1990s, but application of these methods in humanitarian emergencies has been less documented. Recent areas of application of GIS methods in humanitarian emergencies include hazard, vulnerability, and risk assessments; rapid assessment and survey methods; disease distribution and outbreak investigations; planning and implementation of health information systems; data and programme integration; and programme monitoring and evaluation. The main use of GIS in these areas is to provide maps for decision-making and advocacy, which allow overlaying types of information that may not normally be linked. GIS is also used to improve data collection in the field (for example, for rapid health assessments or mortality surveys). Development of GIS methods requires further research. Although GIS methods may save resources and reduce error, initial investment in equipment and capacity building may be substantial. Especially in humanitarian emergencies, equipment and methodologies must be practical and appropriate for field use. Add-on software to process GIS data needs to be developed and modified. As equipment becomes more user-friendly and costs decrease, GIS will become more of a routine tool for humanitarian aid organisations in humanitarian emergencies, and new and innovative uses will evolve. 相似文献
896.
一般持续发展论(下) 总被引:8,自引:1,他引:7
杨开忠 《中国人口.资源与环境》1994,4(2):7-12
本文比较全面地论述了持续发展的由来、概念、目标和战略要素。作者指出,持续发展的提出反映了人类对自身与环境关系的认识进入新阶段;是既满足当代人和局部需要又不危害后代人和全球满足需要能力的发展,包括一般持续发展论、全球持续性、区域持续性和部门持续性。作者认为,社会福利既包括人造产品也包括自然资本,持续发展的目标在于促进社会福利的增长与公平分配,以及生态系统的持续性;而达到持续发展目标的战略要素则包括经济结构的生态现代化、实行以预防为主的环境政策、经济机制的生态现代化、实行有控制的人口转变以及反贫困。在目标和战略要素的论述中,作者提出了发达和发展中国家(地区)应分别实行强持续性和弱持续性。 相似文献
897.
Regression analysis of forest damage by marginal models for correlated ordinal responses 总被引:1,自引:1,他引:0
Studies on forest damage generally cannot be carried out by common regression models, for two main reasons: Firstly, the response variable, damage state of trees, is usually observed in ordered categories. Secondly, responses are often correlated, either serially, as in a longitudinal study, or spatially, as in the application of this paper, where neighbourhood interactions exist between damage states of spruces determined from aerial pictures. Thus so-called marginal regression models for ordinal responses, taking into account dependence among observations, are appropriate for correct inference. To this end we extend the binary models of Liang and Zeger (1986) and develop an ordinal GEEI model, based on parametrizing association by global cross-ratios. The methods are applied to data from a survey conducted in Southern Germany. Due to the survey design, responses must be assumed to be spatially correlated. The results show that the proposed ordinal marginal regression models provide appropriate tools for analysing the influence of covariates, that characterize the stand, on the damage state of spruce. 相似文献
898.
提出基于GSM的可移动危险源处警系统总体方案,在技术实施中考虑现有的可行性通讯资源和低成本实现,采用GSM网络短信息通信,利用带有移动通讯装置和PC机的主站设备来实现。利用GSMAT指令控制收发短信息,并应用数据库对短信息进行管理。对可移动危险源体系、预警方法以及相关关键技术进行较为深入的分析和研究,并在VB环境下编程实现可移动危险源处警系统的基本功能以及通信控件的查询工作方式和事件驱动方式的过程。该研究成果对可移动危险源跟踪、定位、监控,降低可移动危险源的爆炸、泄漏,避免造成重大事故具有一定的实用价值。 相似文献
899.
Anilla Cherian 《Natural resources forum》2007,31(2):128-131
Global climate change is an important cause of biodiversity loss. The conservation, sustainable management and use of biodiversity resources are key factors that can be effectively used to minimize the adverse impacts of global climate change. Efforts to understand and address the linkages between global climate change and biodiversity loss are both urgent and timely. Integrating responses related to these two global environmental challenges is especially relevant for small island developing States (SIDS) because the adverse impacts of climate change can impose severe stresses on biodiversity resources that are fragile, vulnerable and already under stress and the people who depend upon them. This paper argues that comprehensive assessments of adverse impacts of global climate change on the biodiversity resources of SIDS, and an improved understanding of relevant climate change related adaptation measures and sustainable energy policies (that are based on the principles of conservation, sustainable management and use of biodiversity resources) will enable SIDS to become more resilient and to develop better response capacities. 相似文献
900.
Methane emission from rice paddy soils, aerotolerance of methanogens and global thermal warming 总被引:3,自引:0,他引:3
In vitro methane emissions from different rice paddy soils and algal mats were studied under anoxic and atmospheric conditions. Methane production from rice paddy soils cultivating different strains of rice was found to be appreciable under anoxic conditions, but considerably reduced under atmospheric conditions, and dependent on rice cultivars (strains). A contradictory result was obtained with a Gobindabhog cultivated rice field (a strain of rice with aroma), where methane yield under anoxic was greater than that under atmospheric conditions. The results indicated aerotolerance of methanogens or the possible existence of microaerophilic methanogens. The results from algal mats corroborated these findings.Methane has been considered to be an important greenhouse gas contributing significantly to global thermal warming (GTW). Flooded rice paddy fields have been considered to be a most prominent source of abiogenic methane emission, though considerable uncertainty exists regarding the true estimates of methane emission. Factors affecting methane emission and its abatement have been examined. In spite of increasing methane emission, rice cultivation leads to enormous utilization of the green house gas carbon dioxide and release of oxygen to the atmosphere. Thus, the contribution of methane to GTW (from rice paddy cultivation) is more than compensated by carbon dioxide absorption.Appropriate steps have been suggested for the reduction of methane emissions, the most important of which is the restoration of methane sinks. 相似文献