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171.
李栋  蔡博峰 《环境工程》2016,34(2):10-13
基于较高空间分辨率的人口分布(LandScan)和人口活动(Weibo)数据,结合全国垃圾处理设施信息,构建了距离-密度关系曲线,并据此提出了垃圾处理设施布局指数。通过距离-密度关系曲线可分析处理设施潜在环境影响暴露水平的分布情况,而布局指数则从空间覆盖的角度定量测定其影响水平的大小,形成了一种可开展跨地区、跨类型设施布局影响对比研究的手段。基于此方法,以北京、上海为例,对两市共计32座垃圾处理设施的影响水平进行分析和比较。  相似文献   
172.
文章拟建立一种从土霉素菌渣中提取并检测土霉素残留量的高效液相色谱法。用甲醇和冰乙酸作为提取剂提取样品,用分散固相萃取的方法净化样品,净化药剂为石墨化碳黑(GCB)和C18。通过加标回收实验,用高效液相色谱仪检测样品中土霉素含量。选用的色谱柱为PLRP-S,流动相为甲醇和0.05 mol/L草酸,两者比例为35:65(V:V)。检测波长为355 nm,柱温30℃。经检测,土霉素在0.1~2 000 mg/L范围内线性相关系数大于0.999,线性良好。1.0,4.0及8.0mg/g 3个加标水平的土霉素平均回收率范围是80.85%~109.59%,相对标准偏差(RSD)为2.45%~6.38%。土霉素菌渣中土霉素残留量平均为4.741 mg/g。实验表明,该方法具有简单、方便、快速、准确性强、灵敏度高的特点,可以应用于土霉素的分析检测。  相似文献   
173.
The potential to capture carbon from industrial sources and dispose of it for the long-term, known as carbon capture and sequestration (CCS), is widely recognized as an important option to reduce atmospheric carbon dioxide emissions. Specifically, CCS has the potential to provide emissions cuts sufficient to stabilize greenhouse gas levels, while still allowing for the continued use of fossil fuels. In addition, CCS is both technologically-feasible and commercially viable compared with alternatives with the same emissions profile. Although the concept appears to be solid from a technical perspective, initial public perceptions of the technology are uncertain. Moreover, little attention has been paid to developing an understanding of the social and political institutional infrastructure necessary to implement CCS projects. In this paper we explore a particularly dicey issue--how to ensure adequate long-term monitoring and maintenance of the carbon sequestration sites. Bonding mechanisms have been suggested as a potential mechanism to reduce these problems (where bonding refers to financial instruments used to ensure regulatory or contractual commitments). Such mechanisms have been successfully applied in a number of settings (e.g., to ensure court appearances, completion of construction projects, and payment of taxes). The paper examines the use of bonding to address environmental problems and looks at its possible application to nascent CCS projects. We also present evidence on the use of bonding for other projects involving deep underground injection of materials for the purpose of long-term storage or disposal.  相似文献   
174.
Abstract:  The Global Strategy of Plant Conservation states that at least 60% of threatened plant species should be within protected areas. This goal has been met in some regions with long traditions of plant protection. We used gap analysis to explore how particular groups of species of conservation interest, representing different types of natural or anthropogenic rarity, have been covered by protected areas on a national scale in Estonia during the last 100 years. Species-accumulation curves indicated that plant species that are naturally rare (restricted global or local distribution, always small populations, or very rare habitat requirements) needed almost twice as many protected areas to reach the 60% target as plant species that are rare owing to lack of suitable management (species depending on grassland management, moderate forest disturbances, extensive traditional agriculture, or species potentially threatened by collecting). Temporal analysis of the establishment of protected areas suggested that grouping plant species according to the predominant cause of rarity accurately reflected the history of conservation decision making. Species found in very rare habitats have previously received special conservation attention; species dependent on traditional extensive agriculture have been largely ignored until recently. Legislative initiative and new nature-protection schemes (e.g., Natura 2000, network of protected areas in the European Union) have had a positive influence on all species groups. Consequently, the species groups needing similar action for their conservation are sensitive indicators of the effectiveness of protected-area networks. Different species groups, however, may not be uniformly conserved within protected areas, and all species groups should fulfill the target of 60% coverage within protected areas.  相似文献   
175.
大气污染治理是环境保护的重要内容。十二五时期,我国大气污染控制指标需根据国情调整。本研究针对我国目前主要大气污染物SO2、NOX及日益严重的大气复合污染问题,分析了近20年排放量、空气质量变化、控制状况。结果表明:SO2排放总量控制取得一定成效,但缺乏质量指标控制约束;NOX排放增加引发了多种复合型环境问题,部分抵消了SO2控制效果,总体上空气质量并未大幅度提升。对此,借鉴国外控制方法,提出十二五期间应进一步改善控制措施建议:SO2在总量控制基础上加入质量控制,分三类区域以不同标准和手段控制;NOX纳入约束性考核指标;选定重点行业和重点区域,对SO2、NOX采取总量与质量双重控制,并建立相应的政策支撑体系。  相似文献   
176.
Alarm systems are critically important for safe and efficient operations of industrial plants, but many industrial alarm systems are suffering from too many nuisance alarms. This paper proposes a method to classify normal and abnormal data segments and evaluate performance indices for the most commonly used univariate alarm systems. The proposed method consists of three steps. First, piece-wise linear representations are exploited in separating historical data samples of an analog process variable configured with alarms into data segments with same qualitative trends. Second, data segments are classified into normal, abnormal and unclassified conditions via a mean hypothesis test; a required assumption is that data segments in normal and abnormal conditions have different mean values being distinguishable from alarm thresholds. Third, based on the normal and abnormal data, performance indices of univariate alarm systems are calculated, including two newly formulated ones as the false alarm duration ratio and the missed alarm duration ratio. The effectiveness of the proposed method is illustrated by numerical and industrial examples.  相似文献   
177.
Drawing up environmental policy options is a complex activity which involves defining and weighing the merits and risks of various alternative courses of action governments could pursue. In its modern version, this task typically involves formal policy analysis or ‘policy appraisal’, that is, policy work specifically undertaken to generate and evaluate policy options in order to address problems or issues on a policy agenda. Indicators play a powerful but under-investigated role in this process. To shed light on this issue, the paper conducts a case study of the design and evolution of policy indicators in water security policy formulation, examining both their utilization and impact. The paper documents the origins of water security policy indicators; assesses their relevance and influence in policy formulation and identifies the reasons for the emergence of certain preferred indices, despite their having several well-known limitations. In particular, the discussion flags the significance of the political advantages surrounding their ease of use and interpretation, rather than their technical merits, as a key factor affecting the continued utilization and influence of specific indicators in environmental policy and planning.  相似文献   
178.
Freshwater protected areas are rare even though freshwater ecosystems are among the most imperiled in the world. Conservation actions within terrestrial protected areas (TPAs) such as development or resource extraction regulations may spill over to benefit freshwater ecosystems within their boundaries. Using data from 175 lakes across Ontario, Canada, we compared common indicators of fish‐assemblage status (i.e., species richness, Shannon diversity index, catch per unit effort, and normalized‐length size spectrum slopes) to evaluate whether TPAs benefit lake fish assemblages. Nearest neighbor cluster analysis was used to generate pairs of lakes: inside versus outside, inside versus bordering, and bordering versus outside TPAs based on lake characteristics. The diversity and abundance indicators did not differ significantly across comparisons, but normalized‐length size spectrum slopes (NLSS) were significantly steeper in lakes outside parks. The latter indicated assemblage differences (greater abundances of small‐bodied species) and less‐efficient energy transfer through the trophic levels of assemblages outside parks. Although not significantly different, pollution‐ and turbidity‐tolerant species were more abundant outside parks, whereas 3 of the 4 pollution‐intolerant species were more abundant within parks. Twenty‐one percent of the difference in slopes was related to higher total dissolved solids concentrations and angling pressure. Our results support the hypothesis that TPAs benefit lake fish assemblages and suggest that NLSS slopes are informative indicators for aquatic protected area evaluations because they represent compositional and functional aspects of communities.  相似文献   
179.
Agriculturally altered vegetation, especially oil‐palm plantations, is rapidly increasing in Southeast Asia. Low species diversity is associated with this commodity, but data on anuran diversity in oil‐palm plantations are lacking. We investigated how anuran biological diversity differs between forest and oil‐palm plantation, and whether observed differences in biological diversity of these areas is linked to specific environmental factors. We hypothesized that biological diversity is lower in plantations and that plantations support a larger proportion of disturbance‐tolerant species than forest. We compared species richness, abundance, and community composition between plantation and forest areas and between site types within plantation and forest (forest stream vs. plantation stream, forest riparian vs. plantation riparian, forest terrestrial vs. plantation terrestrial). Not all measures of biological diversity differed between oil‐palm plantations and secondary forest sites. Anuran community composition, however, differed greatly between forest and plantation, and communities of anurans in plantations contained species that prosper in disturbed areas. Although plantations supported large numbers of breeding anurans, we concluded the community consisted of common species that were of little conservation concern (commonly found species include Fejervarya limnocharis, Microhyla heymonsi, and Hylarana erythrea). We believe that with a number of management interventions, oil‐palm plantations can provide habitat for species that dwell in secondary forests. Efectos de las Plantaciones de Palma de Aceite sobre la Diversidad de Anuros Tropicales Faruk et al.  相似文献   
180.
With the development of increasingly complex processes and technologies in chemical and manufacturing industries, Process Safety Management (PSM) has been globally recognized as the primary tool for operating companies to reduce process accidents on their industrial sites and the risks posed to their employees and surrounding communities. Yet, industrial facilities are often interdependent and collocated with others. Recognizing this, regional authorities are also applying PSM principles to reduce the cumulative incidents associated with high density industrial areas and the multiplicative risks posed to broader communities. This paper compares Strathcona County Emergency Service (SCES) in Alberta, Contra Costa County Health Service Hazard Material Programs (CCCHSHMP) in California, and Technical Standards & Safety Authority (TSSA) in Ontario and their PSM systems to provide practical recommendations to improve SCES's system. Four aspects of PSM are considered: regulation and guidance, auditing and inspection, annual performance indicators, and public participation. Based on the results of this comparison, we recommend that SCES develop comprehensive PSM regulations based on CSA Z767-17 PSM including clear instructions for assessing technologies and methodologies for consequence analysis. Both worst-case scenarios and alternative scenarios need to be considered as well as the domino effect of primary accidents. Furthermore, regular audits and inspections will ensure compliance with PSM regulations while helping the design of planning, performing, and following-up strategies to ensure effectiveness. In addition, we suggest the use of lagging and leading performance indicators to evaluate the performance of the PSM program. Finally, we recommend using advisory councils or commissions to increase public participation and ensure the representation of stakeholders' perspectives with the PSM system.  相似文献   
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