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1.
Background LCA is the only internationally standardized environmental assessment tool (ISO 14040-43) for product systems, including services and processes. The analysis is done ‘from cradle-to-grave’, i.e. over the whole life cycle. LCA is essentially a comparative method: different systems fulfilling the same function (serving the same purpose) are compared on the basis of a ‘functional unit’ - a quantitative measure of this function or purpose. It is often believed that LCA can be used for judging the (relative) sustainability of product systems. This is only partly true, however, since LCA is restricted to the environmental part of the triad ‘environment/ecology - economy - social aspects (including intergenerational fairness)’ which constitutes sustainability. Standardized assessment tools for the second and the third part are still lacking, but Life Cycle Costing (LCC) seems to be a promising candidate for the economic part. Social Life Cycle Assessment still has to be developed on the basis of known social indicators.Method and Limitations LCA is most frequently used for the comparative assessment or optimization analysis of final products. Materials and chemicals are difficult to analyse from cradle-to-grave, since they are used in many, often innumerable product systems, which all would have to be studied in detail to give a complete LCA of a particular material or substance! This complete analysis of a material or chemical is evidently only possible in such cases where one main application exists. But even if one main application does exist, e.g. in the case of surfactants (chemicals) and detergents (final products), the latter may exist in a great abundance of compositions. Therefore, chemicals and materials are better analysed ‘from cradle-to-factory gate’, leaving the analysis of the final product(s), the use phase and the ‘end-of-life’ phases to specific, full LCAs.Conclusion A comparative assessment of production processes is possible, if the chemicals (the same is true for materials) produced by different methods have exactly the same properties. In this case, the downstream phases may be considered as a ‘black box’ and left out of the assessment. Such truncated LCAs can be used for environmental comparisons, but less so for the (environmental) optimization analysis of a specific chemical: the phases considered as ‘black box’ and left out may actually be the dominant ones. A sustainability assessment should be performed at the product level and contain the results of LCC and social assessments. Equal and consistent system boundaries will have to be used for these life cycle tools which only together can fulfil the aim of assessing the sustainability of product systems.  相似文献   

2.
3.
Venice is famous around the world for its uniqueness and architectural splendours, arts and the history of the “Serenissima Repubblica”, as it was known in the past, but few are aware that Venice economy is strongly dependent on the industrial activities based mainly on the adjacent Porto Marghera area. For many years, the lagoon that physically separates the city from the dry land has avoided association between the concern connected with the pollution derived from these industrial activities and the public perception of Venice. Since 1995, dioxins have appeared as a lagoon contaminant, and their presence, at such a level requiring immediate “in depth” studies and interventions, has been fully realized for decades.  相似文献   

4.
Methods for life cycle assessment of products (LCA) are most often based on the general prevention principle, as opposed to the risk minimization principle. Here, the desirability and feasibility of a combined approach are discussed, along with the conditions for elaboration in the framework of LCA methodology, and the consequences for LCA practice. A combined approach provides a separate assessment of above and below threshold pollution, offering the possibility to combat above threshold impacts with priority. Spatial differentiation in fate, exposure, and effect modelling is identified to play a central role in the implementation. The collection of region-specific data turns out to be the most elaborate requirement for the implementation in both methodology and practice. A methodological framework for the construction of characterization factors is provided. Along with spatial differentiation of existing parameters, two newly introduced spatial parameters play a key role: the sensitivity factor and the threshold factor. The practicability of the proposed procedure is illustrated by an example of its application. Providing a reasonable data availability, the development of separate LCA characterization factors for the respective assessment of pollution levels above and below environmental threshold values seems to be a feasible task that may add to LCA credibility.  相似文献   

5.
Wang C  Yang Y  Zhang Y 《Ambio》2011,40(1):78-87
This article uses a case study in Southeast China to demonstrate how the substantial changes in rural livelihoods have been driven by a combination of “pull” forces from external economic development, and “push” forces from local areas, leading to a shift in rural household economic activities: household outmigration and de-population of the countryside, changes in energy consumption, and most importantly, changes in land uses and eventually, ecological restoration. Such dramatic changes are becoming common across the Chinese countryside. It is pointed out that economic development has generally caused a deterioration of the environment at least at the early period of economic growth, but the positive impacts, especially in some ecosystem in rural areas, have become more apparent.  相似文献   

6.
循环流化床锅炉燃煤技术热电厂生命周期评价   总被引:1,自引:0,他引:1  
运用生命周期评价方法,应用Gabi5.0软件对采用循环流化床锅炉燃煤技术的热电企业进行资源耗竭和环境影响分析,计算各生产单元生命周期清单的全球变暖潜值、酸化效应潜值、富营养化潜值、非生物资源耗竭潜值、人体毒性潜值以及光化学烟雾和臭氧生成潜值等主要环境影响类型,对燃煤发电过程进行生命周期评价。结果表明,全球变暖和非生物资源耗竭为发电运行过程中主要的环境影响因素,分别占53%和15.05%;锅炉燃烧阶段的环境影响最重,占整个生命周期影响值的77.12%,并且除生物耗竭潜值外的其他5项指标均为发电运行阶段各个单元中最高。采用SNCR脱硝技术减少燃烧过程中NOx的排放量,并对该技术方案进行生命周期评价,比较方案实施前后的环境影响。  相似文献   

7.
从LCA角度评价塑料用品与木制用品对环境的影响   总被引:7,自引:0,他引:7  
通过对一次性塑料与纸制用品(木制品)的评价研究的基础上,对木制品与塑料制品从生命周期评价(LCA)的角度上对问题作进一步的探讨和研究,得出结论为塑料制品为环保型产品。  相似文献   

8.
The burning of kerosene in jet turbines is investigated for two reference flights with a Boeing 747-400 and an Airbus A320-200, representing the typical Lufthansa planes for long and middle distance. The ecological evaluation is performed by Life Cycle Assessment (LCA). Formation of condensation trails, which is a specific environmental impact caused by air traffic, has to be considered in addition to established LCA impact categories. Based on the ecological assessment, an improvement assessment is performed. Environmental performance of diesel fuel during the combustion in car engines is analysed based on available publications. The relevant parameters for the environmental impact of the combustion of diesel (aromatics content, reduction of sulphur content, the reduction of the density and raising of the cetane number) are discussed with regard to improvements of the exhaust qualities of kerosene. A reduction of the aromatics content promises to improve the emission of soot which should be further investigated.  相似文献   

9.
Life cycle analysis is one of the tools in the assessment of the sustainability of technological options. It takes into account all effects on the ecosystem and the population which may endanger the possibilities of current and future generations. However, the main bottleneck in current LCA methodologies is the balancing of different effects, being all quantified on different scales. In this work, a methodology is proposed, which allows one to quantify different effects of the production, consumption and disposal of goods, and services on a single scale. The basis of the methodology is the second law of thermodynamics. All production, consumption and disposal processes affecting the ecosystem and the population, are quantified in terms of loss of exergy. The exergy content of a material is the maximum amount of energy which can be transformed into work at given environmental conditions. Next to the elaboration of the methodology, the new approach is illustrated by examples of the production of synthetic organic polymers, inorganic building insulation materials and different waste gas treatment options.  相似文献   

10.
Im Rahmen eines Untersuchungsprogrammes zur Schadstoffemission von Paraffin-, Stearin- und Bienenwachskerzen ohne Farb- und Lackbeimischungen wurden sowohl die Wachse und Dochte als auch die Brandgase dieser Kerzen auf die toxikologisch besonders relevanten Schadstoffklassen der PCDD/PCDF, PAK und kurzkettigen Aldehyde untersucht. Die toxikologische Bewertung kommt selbst bei einem angenommenen „worst case“-Szenario und unter Berücksichtigung von geltenden Grenz- und Richtwerten zu dem Ergebnis, da? von den untersuchten Kerzen kein zus?tzliches Gesundheitsrisiko ausgeht. Exhaust fumes of paraffin, beeswax and stearin candles without any further paint or decorative element were analysed for the toxicological important substance classes of PCDD/PCDF, PAH and short chain aldehydes. The candle waxes and wicks were investigated for chlorinated dioxins, furans and some known precursors. Toxicological risk assessment shows that emissions of the investigated candles are much lower than all administrative limitation values — even under “worst case conditions”. Thus, they do not produce a toxicological risk for human health.  相似文献   

11.
This study was conducted in the Swedish sub-Arctic, near Abisko, in order to assess the direction and scale of possible vegetation changes in the alpine–birch forest ecotone. We have re-surveyed shrub, tree and vegetation data at 549 plots grouped into 61 clusters. The plots were originally surveyed in 1997 and re-surveyed in 2010. Our study is unique for the area as we have quantitatively estimated a 19% increase in tree biomass mainly within the existing birch forest. We also found significant increases in the cover of two vegetation types—“birch forest-heath with mosses” and “meadow with low herbs”, while the cover of snowbed vegetation decreased significantly. The vegetation changes might be caused by climate, herbivory and past human impact but irrespective of the causes, the observed transition of the vegetation will have substantial effects on the mountain ecosystems.  相似文献   

12.
生命周期评价研究进展   总被引:15,自引:2,他引:13  
生命周期评价作为一种评价产品、工艺过程或活动在整个生命周期中环境影响的工具,在国际上广受关注。现对它的概念、发展历程、技术框架、特征及存在问题作简单的介绍,并对其未来发展作了展望。  相似文献   

13.
Tilapia, a tropical freshwater fish native to Africa, is an increasingly important global food commodity. The World Wide Fund for Nature (WWF), a major environmental nongovernmental organization, has established stakeholder dialogues to formulate farm certification standards that promote “responsible” culture practices. As a preface to its “tilapia aquaculture dialogue,” the WWF for Nature commissioned a review of potential certification issues, later published as a peer-reviewed article. This article contends that both the review and the draft certification standards subsequently developed fail to adequately integrate critical factors governing the relative sustainability of tilapia production and thereby miss more significant issues related to resource-use efficiency and the appropriation of ecosystem space and services. This raises a distinct possibility that subsequent certification will promote intensive systems of tilapia production that are far less ecologically benign than existing widely practiced semi-intensive alternatives. Given the likely future significance of this emergent standard, it is contended that a more holistic approach to certification is essential.  相似文献   

14.
Die Ergebnisse der Untersuchung von Wasserproben aus dem Einflu?ereich der Rüstungsaltlast „Dethlinger Teich“ bei Munster/Niedersachsen werden dargestellt und bewertet. Von mehr als 50 untersuchten spezifischen Substanzen wurden Arsenkampfstoffe als Hauptkontaminanten erkannt. Im Rahmen der Gef?hrdungsabsch?tzung wird hier erstmals eine Analysenmethode zur Unterscheidung zwischen anorganisch und organisch gebundenem Arsen vorgestellt. Groundwater analyses in the area of the former munitions depository (World War II) „Dethlinger Teich“ near Munster/Niedersachsen were evaluated. Results from 50 different chemical substances showed that arsenic compounds are the main contaminating chemicals. A new method has been developed to distinguish between morganically- and organically bound compounds. This differentiation is required for risk assessment and evaluation. Also, the relationship of chemical structure and physiological effects in organo arsenic compounds is described.  相似文献   

15.
Callaghan TV  Tweedie CE  Webber PJ 《Ambio》2011,40(6):555-557
Polar and alpine environments are changing rapidly due to increases in temperature, which are amplified in the Arctic, as well as changes in many local factors. The impacts on ecosystems and their function have potential consequences for local residents and the global community. Tundra areas are vast and diverse, and the knowledge of geographical variation in environmental and ecosystem change is limited to relatively few locations, or to remote sensing approaches that are limited mostly to the past few decades. The International Polar Year, IPY, provided a context, stimulus and timely opportunities for re-visiting old research sites and data sets to collate data on past changes, to pass knowledge from old to new generations of researchers and to document environmental characteristics of sites to facilitate detection and attribution of future changes. Consequently, the project “Retrospective and Prospective Vegetation Change in the Polar Regions: Back to the Future,” BTF, was proposed and endorsed as an IPY activity (project #512). With national funding support, teams of researchers re-visited former sites and data sets throughout the Arctic and some alpine regions. These efforts have amounted to a gamut of “BTF” studies that are collectively geographically expansive and disciplinary diverse. A selection of these studies are introduced and presented in the current issue together with a brief synthesis of their findings.  相似文献   

16.
采用生命周期评价法研究比较了北京和上海两地纸塑铝复合包装处置阶段的环境影响。通过现场和资料调研的方式获得此阶段的能量物质的输入输出和环境外排数据。结果表明:北京和上海两地纸塑铝复合包装处置阶段的环境影响潜值分别为-0.428 Pt和9.776 Pt,其主要集中在气候变化、土地占用和无机物对健康的损害三方面;每提高10%的回收率,其环境影响潜值北京和上海可分别降低5.446 Pt和5.799 Pt;上海地区纸塑铝复合包装处置阶段对环境的影响在任何同回收率的情况都要高于北京地区,其主要原因是上海地区填埋产生的温室气体释放量过大和再生企业距离打包点较远。  相似文献   

17.
The increasing attention to agricultural exports and sustainability issues is driving a surge of interest in the life cycle assessment (LCAs) of greenhouse crop production in Albania. Meanwhile, most of the reported agricultural LCAs tend to be generic without considering regionalized environmental sensitivities. In this study, ReCiPe 2016, covering 18 midpoint indicators and 3 endpoint indicators was used to generate a full-fledged cradle-to-farm gate LCA of greenhouse tomatoes in a typical Albanian farm including spatial differentiation and indicators not covered by contemporary LCAs. The most important midpoint categories per 1 ha identified from foreground–background analysis were global warming (2660.4 kg CO2-eq), stratospheric ozone depletion (0.0308 kg CFC11-eq), particulate matter formation (7.99 kg PM2.5-eq), human health and ecosystem ozone formation (8.47 and 14.95 kg NOx-eq), water consumption (2293.23 m3), and terrestrial acidification (42.28 kg SO2-eq). The application of spatial differentiation resulted in higher impacts with about 21% for particulate matter formation, 12% for human health ozone formation, 134% for ecosystem ozone formation, 19% for terrestrial acidification, and 13% for water consumption. The impacts primarily originated from nitrogen-based fertilizer emissions and diesel fuel with the origin of the impact from nitrous oxide (N2O), ammonia volatilization (NH3), nitrogen oxides (NOx), and non-methane volatile organic compounds (NMVOCs). Water consumption was dominated by irrigation water use. Overall, at the endpoint level, 9% and 24% less cumulative damage to human health and ecosystem quality were calculated with respect to the site-generic analysis primarily from the cause-and-effect chain of water consumption (mainly lower water stress index). This affirms the importance of regional considerations in LCA calculations to reflect the impacts accordingly (i.e., the magnitude of impacts, the most relevant midpoint categories, and their relevance on endpoint level) and increase the possibility of making correct conclusions and sub-optimizations, i.e., increase the discriminating power of LCA.  相似文献   

18.

Background, aim and scope  

The applicability of the Whole Effluent Assessment concept for the proof of compliance with the “best available techniques” has been analysed with paper mill wastewater from Germany by considering its persistency (P), potentially bio-accumulative substances (B) and toxicity (T).  相似文献   

19.
“Freely-dissolved” aqueous concentrations of 9 trichlorothrough heptachlorobiphenyls are reported, alongside those in sediments and fish from the R. Severn. For most congeners, BSAFs and lipid-normalised BAFs for pike exceed those for eels. Whilst R. Severn BSAFs are comparable with those for L. Ontario trout and New Bedford Harbour flounder, R. Severn BAFs are 1–2 orders of magnitude lower. This discrepancy may be due to inter-species variability, as well as inter-laboratory differences between operational definitions of “freely-dissolved” aqueous PCB, underlining that the same operational definition must be employed if R. Severn BAFs are extrapolated elsewhere. For eels, correlation of Log Kow with Log BAF is better (R2 = 0.66) than with BSAF (R2 = 0.13), whilst similar correlation coefficients (R2 = 0.81 and 0.82) were observed for pike. When Log Kow is plotted against BSAF and Log BAF for both species combined, better correlation is observed for Log BAF (R2 = 0.65), than BSAF (R2 = 0.36). For both species combined, the observed relationship between Log BAF and Log Kow for trichloro-through heptachlorobiphenyls is: Log BAF = 0.96 * Log Kow −0.24.  相似文献   

20.
The recent claim made in this journal that nuclear bomb tests and the Chernobyl disaster caused distortions in the secondary sex ratio is shown to be a likely artifact of data mining, misused statistics, and misreading of the evidence. In particular, the concept of statistical “significance” and its limitations do not seem to be fully understood, and important confounding factors have not been accounted for.  相似文献   

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