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841.
Modifying the traditional production system and the culture of consumption is necessary to achieve a sustainable society. The product-service system (PSS) business model allows companies to progressively add services to physical products, thus promoting more pro-sustainable business outcomes. The purpose of this work is to verify how a PSS model can contribute to sustainability by analyzing two electric car-sharing projects using a set of five factors. As a methodological strategy, a Systematic Literature Review and a case study of the two projects (VAMO and EMOTIVE) were performed. Findings show benefits generated by both projects as to environmental aspects, mainly related to gases emission. It was also possible to observe social benefits due to income development and environmental awareness. This paper thus contributes to the discussion of the potential of the PSS models and how they can leverage business models toward a more sustainable society. Although the results are applicable only in this case, this article can motivate new projects and contribute to enriching the debate about sustainable solutions, as the literature in this field still provides few case studies showing these types of applications.  相似文献   
842.
本文介绍了土壤生态筛选值的定义以及国外一些国家在污染土壤生态风险评估领域的相关土壤筛选值。由于地理生态、社会文化、行政法规以及标准制定的科学基础等差异使各国基于生态风险的土壤筛选值的制定方法各有特色,导致各国基于生态风险的土壤筛选值名称和筛选值之间存在较大差异。我国的生态风险评价研究起步较晚,目前还没有国家权威机构发布的诸如土壤生态筛选值、生态风险评价技术导则等文件。本文就目前国外一些权威机构推出的并得到广泛认可的相关标准、方法做简要介绍,就国际上不同国家的土壤生态筛选值的制定方法、理论体系、使用策略等进行详细描述,为我国制定相关筛选值的方法体系提供参考,旨在推动我国基于生态风险的污染土壤筛选值的建立和生态风险评估研究。  相似文献   
843.
Marine protected areas (MPAs) are a primary tool for the stewardship, conservation, and restoration of marine ecosystems, yet 69% of global MPAs are only partially protected (i.e., are open to some form of fishing). Although fully protected areas have well-documented outcomes, including increased fish diversity and biomass, the effectiveness of partially protected areas is contested. Partially protected areas may provide benefits in some contexts and may be warranted for social reasons, yet social outcomes often depend on MPAs achieving their ecological goals to distinguish them from open areas and justify the cost of protection. We assessed the social perceptions and ecological effectiveness of 18 partially protected areas and 19 fully protected areas compared with 19 open areas along 7000 km of coast of southern Australia. We used mixed methods, gathering data via semistructured interviews, site surveys, and Reef Life (underwater visual census) surveys. We analyzed qualitative data in accordance with grounded theory and quantitative data with multivariate and univariate linear mixed-effects models. We found no social or ecological benefits for partially protected areas relative to open areas in our study. Partially protected areas had no more fish, invertebrates, or algae than open areas; were poorly understood by coastal users; were not more attractive than open areas; and were not perceived to have better marine life than open areas. These findings provide an important counterpoint to some large-scale meta-analyses that conclude partially protected areas can be ecologically effective but that draw this conclusion based on narrower measures. We argue that partially protected areas act as red herrings in marine conservation because they create an illusion of protection and consume scarce conservation resources yet provide little or no social or ecological gain over open areas. Fully protected areas, by contrast, have more fish species and biomass and are well understood, supported, and valued by the public. They are perceived to have better marine life and be improving over time in keeping with actual ecological results. Conservation outcomes can be improved by upgrading partially protected areas to higher levels of protection including conversion to fully protected areas.  相似文献   
844.
Ongoing loss of biological diversity is primarily the result of unsustainable human behavior. Thus, the long-term success of biodiversity conservation depends on a thorough understanding of human–nature interactions. Such interactions are ubiquitous but vary greatly in time and space and are difficult to monitor efficiently at large spatial scales. However, the Information Age also provides new opportunities to better understand human–nature interactions because many aspects of daily life are recorded in a variety of digital formats. The emerging field of conservation culturomics aims to take advantage of digital data sources and methods to study human–nature interactions and thus to provide new tools for studying conservation at relevant temporal and spatial scales. Nevertheless, technical challenges associated with the identification, access, and analysis of relevant data hamper the wider adoption of culturomics methods. To help overcome these barriers, we propose a conservation culturomics research framework that addresses data acquisition, analysis, and inherent biases. The main sources of culturomic data include web pages, social media, and other digital platforms from which metrics of content and engagement can be obtained. Obtaining raw data from these platforms is usually desirable but requires careful consideration of how to access, store, and prepare the data for analysis. Methods for data analysis include network approaches to explore connections between topics, time-series analysis for temporal data, and spatial modeling to highlight spatial patterns. Outstanding challenges associated with culturomics research include issues of interdisciplinarity, ethics, data biases, and validation. The practical guidance we offer will help conservation researchers and practitioners identify and obtain the necessary data and carry out appropriate analyses for their specific questions, thus facilitating the wider adoption of culturomics approaches for conservation applications.  相似文献   
845.
工业园区温室气体核算方法研究   总被引:1,自引:1,他引:0  
碳达峰碳中和已成为我国重要的国家战略,作为工业发展的重要载体,工业园区贡献了全国50%以上的工业产出和31%左右的碳排放,是我国控碳减碳的重要靶点。准确把握园区碳排放特点,对制定针对性减碳举措意义重大。然而,工业园区温室气体排放核算方法尚未统一,需结合园区特点进行深入探讨。本研究分析了工业园区组成结构与发展特征,将园区的碳排放源归类为能源消费、工业过程和产品使用与废弃物处理处置三大类,比较不同核算方法,提出适合园区特点的温室气体排放清单建议,之后对国家级开发区开展案例研究,揭示其排放结构特征。结果显示,2015—2017年203家园区碳排放强度小幅增加,排放总量持续上升,总排放中超85%为直接排放,但三年内仍分别有100、98和92家园区的间接排放占自身总排放比重超过50%,间接排放是工业园区碳排放不可忽视的重要组份。最后,建议从间接排放占比显著或产城融合程度较高或以单一企业为绝对主体等特殊园区入手,探讨企业、园区、城市等不同层面碳排放核算之间的联系,构建园区低碳发展评价指标体系,推动工业园区温室气体核算标准的建立。  相似文献   
846.
美国恶臭污染管理及测试方法   总被引:3,自引:0,他引:3  
介绍了美国目前的恶臭法规和政策问题。在最近几年中,恶臭标准化问题已经取得了令人瞩目的进展。在美国,大气和废物管理协会(A&WMA)的EE-6恶臭委员会向美国试验与材料协会(ASTM)转交了关于美国试验与材料协会(ASTM)E-679-91方法的建议性替代方案。另外,该方案推荐对嗅觉计使用最小的流量速率3L/min。然而美国大量的恶臭实验室采用了接近20L/min流量速率的欧洲标准。作者提出疑问:美国标准中调整后的嗅觉测量法中采用较低的流量速率和测定值是否与欧洲标准中采用的较高的流量速率和较高的恶臭测定值存在矛盾呢?  相似文献   
847.
非稳定流巷道火灾试验系统的研制   总被引:4,自引:1,他引:3  
介绍了巷道火灾试验系统的构成,测定燃烧区膨胀热阻时测点位置的确定方法,火灾时期烟气温度、壁温及岩体温度、烟流中CO2及O2体积分数、沿程压力和风速等的测试方法及测试仪表精度,系统抗干扰方法,数据采集和处理软件的功能以及测试系统的调试方法.系统采用无补偿导线经济地解决了巷道燃烧区测温热电偶冷端温度补偿的方法,使测温系统误差由过去的10%左右下降到3%.  相似文献   
848.
基于光纤光栅的斜拉索振动参数监测实验研究   总被引:4,自引:2,他引:2  
斜拉索是斜拉桥的主要受力构件 ,对其动力特性进行监测具有重要意义。斜拉索工作条件恶劣 ,现有的测试方法难以实现长期在线监测 ,实现斜拉索的振动在线测量 ,传感器是问题的关键。光纤光栅传感器具有极其优良的稳定性 ,已被证实适用于长期监测 ,在结构监测领域具有非常广泛的应用前景。笔者提出了一种基于光纤光栅传感器的斜拉索动力特性在线监测方法 ,建立了用光纤布拉格光栅作传感器监测斜拉索振动的测量模型 ,为验证该模型建立了模拟试验装置 ,在实验室进行了模拟实验研究 ,并将光纤光栅和传统的电阻应变片两种测量方法进行了实验对比。与传统测试手段相比 ,该方法结构简单 ,成本低 ,并能实现斜拉索动力特性的长期在线监测。  相似文献   
849.
Methods, standards, and regulations that are aimed to reduce indoor air pollution from building materials are critically reviewed. These are classified as content control and emission control. Methods and standards can be found in both of these two classes. In the regulation domain, only content control is enforced in some countries and some regions, and asbestos is the only building material that is banned for building use. The controlled pollutants include heavy metals, radon, formaldehyde, and volatile organic compounds (VOCs). Emission rate control based upon environment chamber testing is very much in the nature of voluntary product labeling and ranking, and this mainly targets formaldehyde and VOC emissions. It is suggested that radon emission from building materials should be subject to similar emission rate control. A comprehensive set criteria and credit-awarding scheme that encourages the use of low-emission building material is synthesized, and how this scheme can be practiced in building design is proposed and discussed.  相似文献   
850.
土地可持续利用的动态度量   总被引:4,自引:0,他引:4  
完善土地持续利用的定量评价指标体系和评价方法乃是今后土地持续利用的重要课题,度量土地利用的可持续性应该遵循动态延续、面向区域、显示过程和突出目标的原则,据此建立一个动态地度量土地利用可持续性的指标体系,包括生产性、结构性、效率性、公平性、稳定性、协调性、恢复性和可控性8个准则层,每一个准则层选择一个综合指标.  相似文献   
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