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101.
目前我国区域性大气复合污染日益严重,迫切需要明晰的控制技术路线指引。本文尝试将情景分析技术应用于区域复合污染控制方案制定中。建立了包括确定主题、驱动力筛选、驱动力预测、排放量预测和情景构建等步骤的情景设计方法。并利用本文建立的方法,详细介绍了在构建区域大气复合污染压力-状态-响应模型的基础上,利用主要驱动力与压力之间的数学关系,进行驱动力预测、构建基线情景和控制情景的方法。讨论了在制定区域协同控制方案过程中,确定满足区域总量控制目标的分区减排原则,并提出实现区域协同控制区域性大气复合污染的控制目标的分区削减方案情景设计的方法建议。 相似文献
102.
Risk-based regulation assumes that risk assessment can evaluate risks against policy objectives. However, policy goals are often ambiguous and require risk assessors to interpret them for use in risk assessment. This risk assessment-policy gap stems partly from normative and imprecise policy language but is rooted more fundamentally in society's uncertain expectations for the environment. Until this uncertainty is resolved, the democratic and regulatory effectiveness of risk regulation will be undermined by ad hoc policy decisions abdicated to risk assessors. 相似文献
103.
The aim of this study is to analyze the environmental agenda in Sweden during the last two decades. A content analysis was made of all articles in a Swedish journal,Miljö-Aktuellt. Further, to elucidate the evolutionary process of problem formulation and reformulation, two cases were investigated, dealing with the impact of plant nutrients and mercury on surface water quality. The transport of heavy metals is an essential component of the ecological process and problem of acidification, and similarly, plant nutrients are part of the concept of eutrophication. Two concepts, the research cycle and the policy cycle, are tentatively applied to the conceptualizations of acidification and eutrophication. Additional data for the latter part of the study is supplied from parliamentary motions during 1973–1989. The substance/media focus of the 1970s was connected to a point-source abatement strategy, which mainly aimed at removing negative effects at a local level. The development of a national preventive strategy is traced in problem formulations related to “processes” going on in the technosphere: wastes, noise, energy production, traffic, and toxic substances. This period lasted from the mid-1970s to the mid-1980s, and the need for improved resource management as a means to control environmental problems has been a generally accepted idea. However, this does not mean that measures actually taken are sufficient in a material balance perspective. Further, in the 1980s there was a strong emphasis upon processes in the ecosphere. This focus also implies source-related policies. To a certain extent, the remedies are within the scope of national capabilities, but the international dimension is becoming increasingly important. Scientific proofs of resource and environment degradation are essential to induce political action and to stimulate international cooperation. From this study, however, it is not possible to assess the existence of any particular policy-triggering information. 相似文献
104.
105.
Péter Batáry Lynn V. Dicks David Kleijn William J. Sutherland 《Conservation biology》2015,29(4):1006-1016
Over half of the European landscape is under agricultural management and has been for millennia. Many species and ecosystems of conservation concern in Europe depend on agricultural management and are showing ongoing declines. Agri‐environment schemes (AES) are designed partly to address this. They are a major source of nature conservation funding within the European Union (EU) and the highest conservation expenditure in Europe. We reviewed the structure of current AES across Europe. Since a 2003 review questioned the overall effectiveness of AES for biodiversity, there has been a plethora of case studies and meta‐analyses examining their effectiveness. Most syntheses demonstrate general increases in farmland biodiversity in response to AES, with the size of the effect depending on the structure and management of the surrounding landscape. This is important in the light of successive EU enlargement and ongoing reforms of AES. We examined the change in effect size over time by merging the data sets of 3 recent meta‐analyses and found that schemes implemented after revision of the EU's agri‐environmental programs in 2007 were not more effective than schemes implemented before revision. Furthermore, schemes aimed at areas out of production (such as field margins and hedgerows) are more effective at enhancing species richness than those aimed at productive areas (such as arable crops or grasslands). Outstanding research questions include whether AES enhance ecosystem services, whether they are more effective in agriculturally marginal areas than in intensively farmed areas, whether they are more or less cost‐effective for farmland biodiversity than protected areas, and how much their effectiveness is influenced by farmer training and advice? The general lesson from the European experience is that AES can be effective for conserving wildlife on farmland, but they are expensive and need to be carefully designed and targeted. 相似文献
106.
氯碱生产中,氯气系统压力不易控制,容易发生泄漏爆炸事故。为解决这一难题,保证安全生产,金川公司化工厂于1996年设计并安装了一套氯气压力自动检测调节系统,经过两年的实际使用,达到了稳定氯气系统压力的良好效果。 相似文献
107.
介绍了研制屋顶电除尘器要解决的几个问题。确定原始设计参数的方法,及其结构特点、技术指标。同时对运行状况作了简要分析。 相似文献
108.
“W型低NOx环保燃烧器”采用先进的复合多级混合式雾化技术,强化喷射、混合和扩散,燃烧充分从而控制NOx生成。 相似文献
109.
Collaborative networks and new ways of knowing 总被引:1,自引:0,他引:1
To move beyond legal and regulatory gridlock around water issues in the California Bay-Delta, a new inter-agency initiative, commonly known as CALFED, was created in 1994. CALFED has been an ongoing experiment in policy innovation. Part of the change in management practice has involved constructing new arenas that engage multiple perspectives and transform regulatory impasse into provisional steps forward. We examine the construction of so-called boundary objects, which are forums and policy instruments that cross group boundaries and foster integrative deliberation. We compare the design and action of two boundary objects created by CALFED, namely the Environmental Water Account (EWA) and the Water Use Efficiency (WUE) program. We find that the presence of the boundary object, in itself, does little to explain the success of each policy experiment. Rather, the answer lies in the types of network interactions that result, along with the way meaning is coproduced. In fact, rather than create new patterns of interrelationship (e.g., between fish habitat advocates and pump station operators), the boundary object might further embed institutionalized routines. To more deeply understand what makes the new institution an integrative one, we introduce the concept of Ways of Knowing which explains how new knowledge emerges from the network of new relationships. 相似文献
110.
The growing water stress both in terms of water scarcity and quality deterioration promotes the development of reclaimed water as a new water resource use. This paper reviewed wastewater reuse practices in China, and the opportunities and challenges of expanding reclaimed water use were analyzed. Rapid urbanization with the increasing of water demand and wastewater discharge provides an opportunity for wastewater reuse. The vast amount of wastewater discharge and low reclaimed water production mean that wastewater reuse still has a great potential in China. Many environmental and economic benefits and successful reclamation technologies also provide opportunities for wastewater reuse. In addition, the overall strategy in China is also encouraging for wastewater reuse. In the beginning stage of wastewater reclamation and reuse, there are many significant challenges to expand wastewater reuse in China including slow pace in adopting urban wastewater reuse programs, the establishment of integrated water resources management framework and guidelines for wastewater reuse programs, incoherent water quality requirements, the limited commercial development of reclaimed water and the strengthening of public awareness and cooperation among stakeholders. 相似文献