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261.
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   
262.
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   
263.
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   
264.
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   
265.
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   
266.
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   
267.
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   
268.
大冶湖表层水和沉积物中重金属污染特征与风险评价   总被引:15,自引:11,他引:4  
于2014年4月采集大冶湖表层水和表层沉积物,用原子吸收分光光度法测定其重金属含量,并基于健康风险评价模型和潜在生态风险指数法开展表层水和沉积物重金属污染的潜在健康风险和生态风险评价.结果表明,表层水和沉积物重金属(Ni、Cd、Cu和Pb)含量平均值分别为49.27、2.19、12.18、12.13μg·L~(-1)和78.46、77.13、650.13、134.22 mg·kg~(-1).富集系数显示,Cd、Cu和Pb均为重度富集,尤其是Cd累积最为明显.与国内典型湖泊重金属污染相比,表层水和沉积物中重金属元素含量均相对较高.表层水和沉积物重金属元素均表现为湖湾处含量较高,中部含量较均匀的分布规律,其来源主要受多种人为活动污染.环境风险评价显示,重金属类化学物质通过饮水途径产生健康风险范围为9.77E-08~1.63E-05 a-1,Ni和Cd是水环境健康风险的优先管理对象.沉积物重金属的潜在生态风险高低为CdCuPbNi,其中Cd是生态风险的贡献元素.  相似文献   
269.
为了科学地诊断出存在的环境问题,实现对生态环境的保护,以重点生态功能区雷山县为例,结合地形、地貌与气候等数据,以格网为评价单元,构建生态系统敏感性评价指标体系。采用层次分析法、区域综合法及格网GIS技术,对评价体系中各指标进行10 m×10 m尺度下的格网化表达,运用栅格数据的空间叠加方法及生态系统敏感性评价模型,综合评价雷山县生态系统敏感性空间格局。结果表明:雷山县生态系统敏感性较高,其中非敏感区和轻度敏感区面积较小,仅占总面积的5%和13.4%;其次是中度敏感区和极度敏感区,分别占总面积的26.3%和17%;高度敏感区面积最大,占总面积的38.3%。  相似文献   
270.
采用德尔菲法、层次分析法和五分制综合评分法,构建了危险废物焚烧厂环境污染控制与风险管理水平评价指标体系。从选址、技术和管理的角度,制定了31个评价指标,并归纳为8个准则层指标群,通过计算权重和对评价指标的赋分,实现对危险废物焚烧厂环境污染控制与风险管理水平的量化评价。应用结果表明:华南某市两家危险废物焚烧厂的环境污染控制与风险管理水平分值分别为3.34和4.38,分别处于良好和先进的水平。  相似文献   
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