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排序方式: 共有651条查询结果,搜索用时 15 毫秒
51.
Conventional approaches to evaluation of environmental programs have tended to limit themselves to restricted measures of program effectiveness. This paper shows how a social learning approach can be incorporated into evaluating public environmental programs. A social learning approach is particularly suited to complex environmental challenges which are inherently difficult to understand, predict, and manage, thus complicating the evaluation process. The paper presents an Australian case study of dryland salinity management where there are major knowledge barriers impeding conventional management techniques. The research presented in this paper focused on evaluating a public demonstration program to track its impact through its design, implementation, and monitoring phases. The paper shows that, by incorporating social learning principles and practices, program evaluation can promote collective action, critical reflection, and increased knowledge to underpin improved environmental management.  相似文献   
52.
环境中苯并(a)芘监测技术及建议   总被引:1,自引:0,他引:1  
环境中BaP是引起人们各类癌症的主要诱发物.叙述了环境中BaP的来源及其浓度状况,列举了国家制定的各项标准中的BaP含量的浓度限值,论述了环境水中和空气中BaP的样品采集、保存、前处理、分析测定及定量监测中应注意的几个问题,提出了监测BaP的4点建议.  相似文献   
53.
东北亚地区沙尘暴监测合作机制研究   总被引:1,自引:1,他引:0  
近年来,东北亚各国重视沙尘暴问题,开展了沙尘暴监测及研究等合作,逐步建立起东北亚地区沙尘暴监测合作机制.合作机制对推动东北亚地区共同治理沙尘暴问题具有积极意义.文章通过分析东北亚主要国家中国、日本和韩国的沙尘暴监测机制,探讨沙尘暴监测的合作机制模式,进而分析合作机制对推动各国在监测方法、管理机制等方面的促进作用.  相似文献   
54.
In a transition to a bio-based economy new ways of monitoring waste-streams and water quality can then contribute to sustainable production processes. As niche innovation, new ways of monitoring face systemic barriers. The present article examines how barriers to change manifest in discursive practices with differing normative attachments and implications. A frame analysis revealed two competing frames: (1) the dominant ‘norm water’ frame in which thresholds of chemical compounds are used to set policy targets; and (2) the contesting ‘living water’ frame, which entails innovative continuous monitoring tools that take into account the ecological effects of chemical compounds. We introduce the concept of interactive reflectivity, as a discursive tool, to collaboratively visualize, scrutinize and overcome discursive barriers to innovations. The stakeholder dialogue shows how systemic barriers are uttered discursively in niches – or other forms of responsible research and innovation – and may hinder change even at the niche-level.  相似文献   
55.
In this final component of a three-part review, we present a national synthesis and evaluation of approaches for monitoring, assessing and reporting estuarine condition across Australia. Progress is evaluated against objective criteria that together provide a model of international best practice. We critically assess the limitations, inconsistencies and gaps that are evident across Australian jurisdictions, and identify common obstacles to future progress. Major strengths and successes are also highlighted, together with specific examples of best practice from around Australia that are transferable to other States and beyond. Significant obstacles to greater national coordination of monitoring and reporting practices include inconsistent spatial scales of management, pluralistic governance structures and the lack of any overarching legislation. Nonetheless, many perceptible advances have been made over the last decade across Australia in estuarine monitoring and health assessment, and there is great potential for further progress. Finally, we provide a list of recommendations to address some of the most pressing limitations and gaps, and support improved future monitoring, assessment and reporting for Australian estuaries.  相似文献   
56.
通过分析我国污染场地含水层监测现状和污染场地环境管理需求,指出我国污染场地含水层监测的不足之处并探讨了我国污染场地含水层监测技术研发趋势.当前,我国污染场地含水层监测主要以地下水监测为主,且监测仪器设备简陋陈旧、技术手段落后,不能满足数量日益增长的污染场地环境管理需求,急需发展一批新型、高效、经济、实用的监测技术和监测...  相似文献   
57.
To evaluate the effectiveness of emission control regulations designed for reducing air pollution, chemically resolved PM2.5 data have been collected across Canada through the National Air Pollution Surveillance network in the past decade. 24-hr time integrated PM2.5 collected at seven urban and two rural sites during 2010-2016 were analyzed to characterize geographical and seasonal patterns and associated potential causes. Site-specific seven-year mean gravimetric PM2.5 mass concentrations ranged from 5.7 to 9.6 µg/m3. Seven-year mean concentrations of SO42?, NO3?, NH4+, organic carbon (OC), and elemental carbon (EC) were in the range of 0.68 to 1.6, 0.21 to 1.5, 0.27 to 0.71, 1.1 to 1.9, and 0.37 to 0.71 µg /m3, accounting for 10.8%-18.1%, 3.7%-16.7%, 4.7%-7.4%, 18.4%-21.0%, and 6.4%-10.6%, respectively, of gravimetric PM2.5 mass. PM2.5 and its five major chemical components showed higher concentrations in southeastern Canada and lower values in Atlantic Canada, with the seven-year mean ratios between the two regions being on the order of 1.7 for PM2.5 and 1.8-7.1 for its chemical components. When comparing the concentrations between urban and rural sites within the same region, those of SO42? and NH4+ were comparable, while those of NO3?, OC, and EC were around 20%, 40%-50%, and 70%-80%, respectively, higher at urban than rural sites, indicating the regional scale impacts of SO42? and NH4+ and effects of local sources on OC and EC. Monthly variations generally showed summertime peaks for SO42? and wintertime peaks for NO3?, but those of NH4+, OC, and EC exhibited different seasonality at different locations.  相似文献   
58.
通过分析传统扬尘污染防治模式的弊端,提出了一种“精准监测、排量切入、总量考核、职责共担”的新模式。该模式在技术手段上使用以扬尘在线监测数据为基准的扬尘排放量计算模式,以及基于机器学习的扬尘源排放量计算方法,实现了扬尘排放量的自动、实时、在线计算;在管理手段上将传统的扬尘浓度点控制转变为易扬尘单位扬尘排量控制,通过总量控制、指标分解,增强了政府与企业对于环境效益的职责分工,有助于将扬尘防控责任有效落实,实现对扬尘污染的精细化、常态化管控。  相似文献   
59.
借鉴环境风险源目标管理的理念,按照“分区、分类、分级”监测的原则,建立了化工园区地下水环境状况调查监测布点方法体系,并以某化工园区为示例展开应用研究。结果显示,该方法能对化工园区不同区域、不同类型、不同级别的地下水污染源构建差异化监测网络,解决化工园区地下水污染多元化监测布点问题,可为化工园区地下水环境状况调查监测布点方案的拟定或优化调整提供工作参考。  相似文献   
60.
何赟  魏化军 《上海环境科学》2003,22(11):805-807
对大型锅炉房(燃煤、燃气、燃油)的噪声源进行测试分析.给出了隔声、吸声、消声量的计算公式.同时针对燃煤、燃油、燃气锅炉房的噪声污染.采取了不同的治理措施.取得了较好的治理效果。  相似文献   
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