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991.
Marta HervaAuthor VitaeAmaya FrancoAuthor Vitae Eugenio F. CarrascoAuthor VitaeEnrique RocaAuthor Vitae 《Journal of Cleaner Production》2011,19(15):1687-1699
This paper reviews a series of environmental indicators developed in the last years that were found suitable to be applied at corporate level for the evaluation of production processes and products. The indicators reviewed in this paper were classified into four main groups: 1) Indicators of Energy and Material Flows; 2) Indicators with a Territorial Dimension; 3) Indicators of Life-Cycle Assessment; 4) Indicators of Environmental Risk Assessment. Integrative and single index indicators such as the ecological footprint or carbon footprint were found as the most appealing for enterprises, although there is a need to advance in the field to combine the simplicity required at corporate level for tracking and reporting environmental data, and the scientific rigor and transparency necessary to make the scores reliable. Hence, for each of the indicators revised it was stated what they do and do not measure so that misleading information was not used for decision making at corporate level. 相似文献
992.
A composting toilet using sawdust as a matrix has the potential to trap pathogens that might occasionally be contained in human
feces. Therefore, care should be taken when handling the sawdust. It should also be noted that pathogenic viruses tend to have stronger
tolerance than pathogenic bacteria. The fates of several species of coliphages, T4, , Q and MS2, in sawdust were investigated as
a viral model. The fates of coliphages were significantly different among them, and they changed in response to temperature and the
water content of the sawdust. As the results, T4 coliphage had the strongest tolerance and Q had the weakest one in sawdust. It was
estimated the days required to decrease virus to a safe level based on a risk assessment. According to the rates of Q and T4, 15 days
and 167 days were required respectively for a safe level of infection risk based on actually operated composting toilet condition. Thus,
it was significantly different depending on the species and sawdust conditions. 相似文献
993.
基于污染物受纳量的城镇生活污水处理率指标研究 总被引:1,自引:0,他引:1
我国通过污水处理率来评价生活污水处理水平,但污水处理率仅考虑了污水处理设施进水处理的水量,忽略了雨污合流、地下水混入、抽取河水处理等原因导致的污染物收集水平不足.以成都市岷江外江流域为研究区域,开展了城镇生活污水收集和评价指标优化研究,提出了基于污染物受纳量的城镇生活污水污染物处理率概念和核算方法体系,在划分控制单元基础上,核算生活污水污染物的产生量和处理量.研究发现,该流域污水处理厂进水浓度普遍偏低,进水水质存在季节性波动,说明可能存在丰水期雨水、河水或地下水混入稀释的情况,枯水期的进水数据更能反映区域生活污水排放情况;传统污水处理率计算显示该流域污水处理率高于100%,但全流域的CODCr、氨氮和总磷污染物处理率分别为37.50%、36.25%和30.14%,与该流域的水环境质量特征和污水管网建设水平相符;在污水管网未完善的地区,采用污染物处理率更能有效评价和反映区域污水收集和处理程度. 相似文献
994.
US EPA's Community Multiscale Air Quality modeling system(CMAQ) with Process Analysis tool was used to simulate and quantify the contribution of individual atmospheric processes to PM_(2.5) concentration in Qingdao during three representative PM_(2.5) pollution events in the winter of 2015 and 2016. Compared with the observed surface PM_(2.5) concentrations, CMAQ could reasonably reproduce the temporal and spatial variations of PM_(2.5) during these three events. Process analysis results show that primary emissions accounted for 72.7%–93.2% of the accumulation of surface PM_(2.5) before and after the events.When the events occurred, primary emissions were still the major contributor to the increase of PM_(2.5) in Qingdao, however the contribution percentage reduced significantly,which only account for 51.4%–71.8%. Net contribution from horizontal and vertical transport to the accumulation of PM_(2.5) was also positive and its percentage increased when events occurred. Only 1.1%–4.6% of aerosol accumulation was due to PM processes and aqueous chemical processes before and after events. When the events occurred,contribution from PM processes and aqueous chemistry increased to 6.0%–11.8%. Loss of PM_(2.5) was mainly through horizontal transport, vertical transport and dry deposition, no matter during or outside the events. Wet deposition would become the main removal pathway of PM_(2.5), when precipitation occurred. 相似文献
995.
生态系统价值核算是开展生态系统保护成效评估的重要手段,也是支撑生态文明制度体系建设的关键技术之一.指标体系的设定是开展生态系统价值核算的重要前提和基础,但当前生态系统价值还缺少统一的核算指标,因此,在一定程度上制约了生态系统价值在生态系统管理与决策中的应用.在总结归纳当前生态系统价值相关指标体系的基础上,以服务于生态系统管理和相关绩效考核为目标,提出了包括生物生产性、人类收益性、保护成效性、实际发生性、实物度量性、数据可获性、持续更新性、非危害性在内的8项生态系统价值核算原则,筛选形成了包括7个功能类别、15个一级科目和26个二级科目的生态系统价值核算指标体系,并针对实物量达到一定数值才能形成服务的指标设定了核算基准.以厦门市为例探讨了这一指标体系的应用能力,其不仅包括了厦门市主要生态系统服务,而且体现了厦门市作为沿海旅游城市的区域特色.在此基础上,探索了开展生态系统价值统计核算的可能途径,主要包括建立生态系统价值统计核算公式,编制技术导则,开展培训、制定定期发布制度等,旨在为实现生态系统价值的业务核算及其应用提供技术支撑. 相似文献
996.
Ayomi Jayarathne Buddhi Wijesiri Prasanna Egodawatt Godwin A. Ayoko Ashantha Goonetilleke 《环境科学学报(英文版)》2019,31(9):85-95
Metal pollution of stormwater runoff can cause potential toxic impacts on the receiving water environment and human health. Effective pollution mitigation requires accurate stormwater quality modeling. Even though a significant knowledge base exists on the factors influencing metal build-up on urban roads, very limited studies have investigated how metal–particulate interaction influences metal build-up. This study quantitatively assessed the influence of particulate characteristics, together with vehicular traffic and land use, on the build-up of Zn, Cu, Pb, Cr, Ni and Cd on urban roads. The study outcomes revealed that the variability in metal build-up is highly influenced by the variability associated with metal adsorption to particulates. The percentage contribution from particulate properties influencing metal adsorption in the case of 150 μm size road dust particles was found to be higher(Zn 44%, Cu 52%, Cr 16%, Ni 27% and Cd 45%) when compared to traffic and land use characteristics(Zn 21%, Cu 13%, Cr and Ni 10% and Cd 34%). Similar adsorption behavior was noted for metals associated with 150 μm size road dust particles. Among different particulate properties influencing metal adsorption, effective cation exchange capacity showed a strong positive relationship with the build-up of Cd compared to other metals,highlighting the potential role of Cd in stormwater quality as a readily available metal. The build-up of metals such as Cr and Ni are highly influenced by metal oxides of Al, Fe and Mn and clay forming minerals, indicating that Cr and Ni are relatively stable in nature. 相似文献
997.
基于城市生态安全内涵,运用PSR(压力-状态-响应)模型建立了宁波市生态安全评价指标体系,并以最大信息熵原理(MIEP)为基础,自组织特征映射神经网络(SOFM)为算法,借助MATLAB数学软件为计算平台,从复杂系统结构演化的角度提出了城市生态安全评价模型.最后,用MIEP模型对宁波市2002—2011年的城市生态安全进行评价.结果表明,2002—2011年宁波市生态安全水平逐年提高,2002—2009年处于临界安全状态,2010、2011年处于较安全状态.由于MIEP模型能较好地体现城市生态安全的时空演变动力学特性,连接权值的获取避免了人为设定的主观性,故在城市生态安全评价中有较明显的优势,且在预测上有一定的潜力. 相似文献
998.
《水污染防治行动计划》中明确提出了开展地下水污染修复试点工作,我国地下水污染的严重性正引起广泛关注,也面临着迫切的修复需求,因此启动地下水污染修复已经刻不容缓。文章介绍了发达国家的地下水污染修复经验,主要包括具备完善的法律制度、实施地下水污染源分类管理、形成完善的指南和规范。为应对我国地下水污染修复基础薄弱,落实水污染防治行动计划、全国地下水污染防治规划等国家政策需求,建立地下水污染分类管理体系,按照修复目标确定、修复方案筛选、修复工程设计、实施、监测和终止等规范程序要求开展工作,实施地下水污染修复示范工程,为全面推进地下水污染修复和改善地下水环境质量提供支撑。 相似文献
999.
1000.