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301.
The continuously increasing solid waste generation worldwide calls for management strategies that integrate concerns for environmental sustainability. By quantifying environmental impacts of systems, life cycle assessment (LCA) is a tool, which can contribute to answer that call. But how, where and to which extent has it been applied to solid waste management systems (SWMSs) until now, and which lessons can be learnt from the findings of these LCA applications? To address these questions, we performed a critical review of 222 published LCA studies of SWMS. We first analysed the geographic distribution and found that the published studies have primarily been concentrated in Europe with little application in developing countries. In terms of technological coverage, they have largely overlooked application of LCA to waste prevention activities and to relevant waste types apart from household waste, e.g. construction and demolition waste. Waste management practitioners are thus encouraged to abridge these gaps in future applications of LCA. In addition to this contextual analysis, we also evaluated the findings of selected studies of good quality and found that there is little agreement in the conclusions among them. The strong dependence of each SWMS on local conditions, such as waste composition or energy system, prevents a meaningful generalisation of the LCA results as we find it in the waste hierarchy. We therefore recommend stakeholders in solid waste management to regard LCA as a tool, which, by its ability of capturing the local specific conditions in the modelling of environmental impacts and benefits of a SWMS, allows identifying critical problems and proposing improvement options adapted to the local specificities.  相似文献   
302.
Non‐native species cause changes in the ecosystems to which they are introduced. These changes, or some of them, are usually termed impacts; they can be manifold and potentially damaging to ecosystems and biodiversity. However, the impacts of most non‐native species are poorly understood, and a synthesis of available information is being hindered because authors often do not clearly define impact. We argue that explicitly defining the impact of non‐native species will promote progress toward a better understanding of the implications of changes to biodiversity and ecosystems caused by non‐native species; help disentangle which aspects of scientific debates about non‐native species are due to disparate definitions and which represent true scientific discord; and improve communication between scientists from different research disciplines and between scientists, managers, and policy makers. For these reasons and based on examples from the literature, we devised seven key questions that fall into 4 categories: directionality, classification and measurement, ecological or socio‐economic changes, and scale. These questions should help in formulating clear and practical definitions of impact to suit specific scientific, stakeholder, or legislative contexts. Definiendo el Impacto de las Especies No‐Nativas  相似文献   
303.
Understanding risks from the human-mediated spread of non-indigenous species (NIS) is a critical component of marine biosecurity management programmes. Recreational boating is well-recognised as a NIS pathway, especially at a regional scale. Assessment of risks from this pathway is therefore desirable for coastal environments where recreational boating occurs. However, formal or quantitative risk assessment for the recreational vessel pathway is often hampered by lack of data, hence often relies on expert opinion. The use of expert opinion itself is sometimes limited by its inherent vagueness, which can be an important source of uncertainty that reduces the validity and applicability of the assessment. Fuzzy logic, specifically interval type-2 fuzzy logic, is able to model and propagate this type of uncertainty, and is a useful technique in risk assessment where expert opinion is relied upon. The present paper describes the implementation of a NIS fuzzy expert system (FES) for assessing the risk of invasion in marine environments via recreational vessels. The FES was based on expert opinion gathered through systematic elicitation exercises, designed to acknowledge important uncertainty sources (e.g., underspecificity and ambiguity). The FES, using interval type-2 fuzzy logic, calculated an invasion risk value (integrating NIS infection and detection probabilities) for a range of invasion scenarios. These scenarios were defined by all possible combinations of two vessel types (moored and trailered), five vessel components (hull, deck, internal spaces, anchor, fishing gear), two infection modes (fouling, water/sediment retention) and six frequently visited marine habitats (marina, mooring, farm, ramp, wharf, anchorage). Although invasion risk values determined using the FES approach was scenario-specific, general patterns were identified. Moored vessels consistently showed higher invasion risk values than trailered vessels. Invasion risk values were higher for anchorages, moorings and wharves. Similarly, hull-fouling was revealed as the highest infection risk mode after pooling results across all habitats. The NIS fuzzy expert system presented here appears as a valuable prioritising and decision-making tool for NIS research, prevention and control activities. Its easy implementation and wide applicability should encourage the development and application of this type of system as an integral part of biosecurity, and other environmental management plans.  相似文献   
304.
Abstract: Systematic conservation assessment (an information‐gathering and prioritization process used to select the spatial foci of conservation initiatives) is often considered vital to conservation‐planning efforts, yet published assessments have rarely resulted in conservation action. Conservation assessments may lead more directly to effective conservation action if they are reoriented to inform conservation decisions. Toward this goal, we evaluated the relative priority for conservation of 7 sites proposed for the first forest reserves in the Union of the Comoros, an area with high levels of endemism and rapidly changing land uses in the western Indian Ocean. Through the analysis of 30 indicator variables measured at forest sites and nearby villages, we assessed 3 prioritization criteria at each site: conservation value, threat to loss of biological diversity from human activity, and feasibility of reserve establishment. Our results indicated 2 sites, Yiméré and Hassera‐Ndrengé, were priorities for conservation action. Our approach also informed the development of an implementation strategy and enabled an evaluation of previously unexplored relations among prioritization criteria. Our experience suggests that steps taken to ensure the closer involvement of practitioners, include a broader range of social data, encourage stakeholder participation, and consider the feasibility of conservation action can improve the relevance of assessments for conservation planning, strengthen the scientific basis for conservation decisions, and result in a more realistic evaluation of conservation alternatives.  相似文献   
305.
Life cycle assessment (LCA) is increasingly used in waste management to identify strategies that prevent or minimise negative impacts on ecosystems, human health or natural resources. However, the quality of the provided support to decision- and policy-makers is strongly dependent on a proper conduct of the LCA. How has LCA been applied until now? Are there any inconsistencies in the past practice? To answer these questions, we draw on a critical review of 222 published LCA studies of solid waste management systems. We analyse the past practice against the ISO standard requirements and the ILCD Handbook guidelines for each major step within the goal definition, scope definition, inventory analysis, impact assessment, and interpretation phases of the methodology. Results show that malpractices exist in several aspects of the LCA with large differences across studies. Examples are a frequent neglect of the goal definition, a frequent lack of transparency and precision in the definition of the scope of the study, e.g. an unclear delimitation of the system boundaries, a truncated impact coverage, difficulties in capturing influential local specificities such as representative waste compositions into the inventory, and a frequent lack of essential sensitivity and uncertainty analyses. Many of these aspects are important for the reliability of the results. For each of them, we therefore provide detailed recommendations to practitioners of waste management LCAs.  相似文献   
306.
某货车侧翻水污染事件的环境损害评估方法探索   总被引:1,自引:0,他引:1  
随着我国进入突发水污染事件高发期,面临的水环境形势日益严峻.为了震慑环境污染行为,保证受损的环境资源得到恢复和补偿,量化突发性水污染事件造成的经济损失显得至关重要.本文以重庆市某货车侧翻污染事件为例,构建了一套突发水污染事件环境损害的量化评估方法,并用该方法从财产损害、生态环境资源损害、应急处置行政事务投入费用和调查评估费用这4个方面量化了该事件造成的环境污染损害.  相似文献   
307.
In Latin America and the Caribbean, river restoration projects are increasing, but many lack strategic planning and monitoring. We tested the applicability of a rapid visual social–ecological stream assessment method for restoration planning, complemented by a citizen survey on perceptions and uses of blue and green infrastructure. We applied the method at three urban streams in Jarabacoa (Dominican Republic) to identify and prioritize preferred areas for nature-based solutions. The method provides spatially explicit information for strategic river restoration planning, and its efficiency makes it suitable for use in data-poor contexts. It identifies well-preserved, moderately altered, and critically impaired areas regarding their hydromorphological and socio-cultural conditions, as well as demands on green and blue infrastructure. The transferability of the method can be improved by defining reference states for assessing the hydromorphology of tropical rivers, refining socio-cultural parameters to better address river services and widespread urban challenges, and balancing trade-offs between ecological and social restoration goals.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01565-3.  相似文献   
308.
本文在实际开展汽车制造项目环境影响评价的基础上,对汽车制造项目生产工艺及产污环节进行梳理,重点对废气、废水、固废、噪声源强核算过程和方法进行解析,对污染防治措施论证内容进行探讨,同时从清洁生产水平分析、政策相符性分析等方面的技术要点进行总结整理,梳理了目前汽车制造项目环评文件编制的要点核心,指出汽车整车制造项目环境影响评价中应关注的重点问题,主要在于挥发性有机废气源强和含氮、磷及重金属废水源强核算、物料平衡等,为下阶段汽车制造项目建设和环境管理提供参考。  相似文献   
309.
应用相平衡分配法建立湘江衡阳段沉积物重金属质量基准   总被引:4,自引:2,他引:2  
韩超南  秦延文  郑丙辉  张雷  曹伟 《环境科学》2013,34(5):1715-1724
采集湘江衡阳段29个站点的表层沉积物样品,测定沉积物中4种重金属(Cu、Pb、Zn和Cd)含量及赋存形态、以及孔隙水中重金属含量,根据相平衡分配法的基本理论,考虑参与沉积物-水相平衡分配的重金属组成,实测法计算重金属的沉积物-水相平衡分配系数(Kp),分别引用美国EPA制定保护水生生物不受重金属慢性毒性影响的基本连续浓度(CCC)和我国地表水环境质量标准(GB 3838-2002)Ⅰ类水质标准,建立两种湘江衡阳段沉积物重金属质量基准(SQC)进行对比分析,其中基于美国CCC建立的湘江衡阳段沉积物重金属质量基准与国内外研究成果相比可比性较好,4种重金属(Cu、Pb、Zn和Cd)的SQC值分别为64.62、55.57、1 360.40和2.34μg.g-1,此SQC具有保护长期生活于沉积物中的底栖生物不受重金属慢性毒性影响的意义.通过单因子评价法将湘江衡阳段沉积物中重金属总量与沉积物质量基准值(SQC)进行比较,结果表明,湘江衡阳段沉积物中Cd和Pb含量水平对底栖生物具有较大的慢性毒性影响,Cd污染不容忽视.  相似文献   
310.
微气泡臭氧催化氧化-生化耦合工艺深度处理煤化工废水   总被引:7,自引:1,他引:6  
刘春  周洪政  张静  陈晓轩  张磊  郭延凯 《环境科学》2017,38(8):3362-3368
采用微气泡臭氧催化氧化-生化耦合工艺对煤化工废水生化出水进行深度处理,考察耦合系统处理性能及不同臭氧投加量和进水COD量比值的影响.结果表明,微气泡臭氧催化氧化处理能够有效降解废水中难降解含氮芳香族污染物,去除部分COD并释放氨氮,显著提高废水可生化性,臭氧利用率接近100%,无需进行臭氧尾气处理;同时为生化处理提供充足溶解氧(DO),实现生化处理对COD和氨氮的进一步有效去除,生化处理无需曝气.在系统出水回流比为30%、臭氧投加量和进水COD量之比为0.44 mg·mg~(-1)的运行条件下,耦合系统处理性能较好.微气泡臭氧催化氧化处理对COD去除率为42.5%,臭氧消耗量与COD去除量比值为1.38 mg·mg~(-1),臭氧利用率为98.0%;生化处理对COD去除率为42.3%;耦合系统整体COD去除率为66.7%,最终平均出水COD浓度为91.5 mg·L~(-1),估算整体臭氧消耗量与COD去除量比值为0.68 mg·mg~(-1),具有较优的技术经济性能.  相似文献   
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