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471.
472.
Companies on the Scale   总被引:1,自引:0,他引:1  
A determination of the sustainability performance of a company ought to fulfill certain requirements. It has to take into account the direct impacts from on-site processes as well as indirect impacts embodied in the supply chains of a company. This life cycle thinking is the common theme of popular footprint analyses, such as carbon, ecological, or water footprinting. All these indicators can be incorporated into one common and consistent accounting and reporting scheme based on economic input−output analysis, extended with data from all three dimensions of sustainability. We introduce such a triple-bottom-line accounting framework and software tool and apply it in a case study of a small company in the United Kingdom. Results include absolute impacts and relative intensities of indicators and are put into perspective by a benchmark comparison with the economic sector to which the company belongs. Production layer decomposition and structural path analysis provide further valuable detail, identifying the amount and location of triple-bottom-line impacts in individual upstream supply chains. The concept of shared responsibility has been applied to avoid double-counting and noncomparability of results. Although in this work we employ a single-region model for the sake of illustration, we discuss how to extend our ideas to international supply chains. We discuss the limitations of the approach and the implications for corporate sustainability.  相似文献   
473.
Abstract

This study presents an ichnotaxonomical assessment of bird footprints from a coastal plain setting in the Eocene lower to middle Aspelintoppen Formation in Brongniartfjellet and Storvola, Svalbard. These footprints are unique evidence for Paleogene birds from Svalbard and the second evidence of Paleogene avifauna of the Arctic (along with scarce fossil remains from Ellesmere Island). The analyzed footprints are assigned to six ichnotaxa belonging to three ichnofamilies: Aquatilavipes isp., avian footprint morphotype A and B (ichnofamily Avipedidae); Gruipeda cf. G. abeli, Gruipeda cf. G. dominguensis (ichnofamily Gruipedidae); and Gyeongsangornipes isp. (ichnofamily unknown). Associated invertebrate ichnofossils include Helminthoidichnites tenuis, Cochlichnus anguineus, and Helminthopsis isp. The avian footprints reflect small, medium-sized and rare large birds that can be morphologically compared to those of modern relatives including crane, heron, plover, moorhen, gallinule, oystercatcher and curlew. It is also proposed that in situ sets of shorebird footprints showing a preferred orientation, not composing trackways and showing overprinting, can be used as an indicator of the position and orientation of the shoreline.  相似文献   
474.
JAMES DWYER 《Bioethics》2009,23(9):497-502
In this paper, I explore one way to bring bioethics and environmental ethics closer together. I focus on a question at the interface of health, sustainability, and justice: How well does a society promote health with the use of no more than a just share of environmental capacity? To address this question, I propose and discuss a mode of assessment that combines a measurement of population health, an estimate of environmental sustainability, and an assumption about what constitutes a fair or just share. This mode of assessment provides an estimate of the just and sustainable life expectancy of a population. It could be used to monitor how well a particular society promotes health within just environmental limits. It could also serve as a source of information that stakeholders use when they deliberate about programs, policies, and technologies. The purpose of this work is to focus attention on an ethical task: the need to fashion institutions and forms of life that promote health in ways that recognize the claims of sustainability and justice.  相似文献   
475.
Continuous measurements of the net CO2 flux exchanged in a mixed forest with the atmosphere were performed over 5 years at the Vielsalm experimental site. The carbon sequestration at the site was deduced by a summation of the measurements. Problems associated with this summation procedure were discussed. The carbon sequestration in the ecosystem was presented and its interannual variability was discussed. An estimation of the night flux correction was given. The correction was applied by replacing measurements made during quiet nights by a parameterization. The impact of the correction was shown to vary between 10 and 20% of the uncorrected flux, according to the year. The need to include the storage flux during turbulent periods was emphasized: its neglect leads to an error which will be greater than the one it tries to correct. It was also shown that the heterogeneity of the site made it necessary to split the data into separate series corresponding to the different vegetation patches and to fill the data gaps by using an algorithm that takes account of the weather conditions. Two series were defined, one corresponding to a beech subplot, the other to a conifer subplot. The uncertainty owing to the data split and the data gap‐filling was about 15–20% annually. The carbon sequestration was then analysed in both the subplots. The length of the growing season was about 210 days in the beech and 240 days in the conifer. The carbon sequestration over 5 years was 2.28 kg C m2?2 in the beech and 3.58 kg C m2?2 in the conifer. The main difference between the species appeared in spring, between March and May, when the beeches were leafless. Significant interannual variations were observed in both the subplots. They appeared mainly in summer and were primarily because of the variations in the radiation and air humidity regimes. In addition, an impact of the interannual variation of the vegetation area index (VAI) and of the leaf initiation date was observed in the beech. Finally, a decline of the carbon sequestration efficiency of the ecosystem during the season was observed in both the subplots. It was because of neither the variation in any climatic variables nor VAI variation.  相似文献   
476.
477.
冯伟民 《古生物学报》2020,59(2):160-162
我国三峡地区发现的已知最古老足迹化石,使远古动物开启步行时代前推到了5.51亿年前,为两侧对称动物在晚前寒武纪末就已出现提供了依据,也为寒武纪生命大爆发可能开启于寒武纪前提供了有意义的信息。这一发现进一步提高了足迹化石在研究古老动物行为和了解重大生物事件所具有的价值。  相似文献   
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