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71.
The tendency towards a homogenous mode of development modelled on that of Western countries means that sustainable development has become increasingly urgent. It is necessary to thoroughly redefine products and their expected performances in such a way that the consequences are compatible with sustainable development. In the domain of product design, this means that it is no longer sufficient to use assessment tools “after the fact” to check the impact of products whose functional unit (FU) was defined prior to production; it is now necessary to rethink the definition of the FU itself. This article aims to present an approach based on a combination of life cycle analysis methods and problem-solving by constraint satisfaction. This original approach makes it possible to vary the design of the different dimensions of the FUs of a complex system and thus to make it easier to identify the best architecture along with the best functional definition of the system. In this study, the EcoCSP approach is applied to define the functional performances of an ecological passenger ferry. The complexity of couplings between subsystems and the sheer number of those subsystems mean that the designer has to use “intelligent” tools. These simulate a great number of scenarios and help him/her to fine-tune the system and make the right technological choices with regard to the right functional specifications.  相似文献   
72.
To collect regional information on internal levels of pollutants in humans in Flanders, 1196 mother–child pairs were systematically recruited in 2002–2003 via 25 maternities across Flanders. Cd, Pb, PCB congeners 118, 170, 138, 153 and 180, p,p′-DDE — a key metabolite of DDT- and hexachlorobenzene (HCB) were measured in cord blood or plasma. Cd was detected in 64% of the samples (geometric mean 0.21 µg/L cord blood). p,p′-DDE (110 ng/g plasma lipids) and Pb (14.7 µg/L blood), were measurable in nearly all samples. The individual PCB congeners could be detected in 40 to 81% of the newborns (138 + 153 + 180 = 64.4 ng/g plasma lipids). HCB (18.9 ng/g plasma lipids) and dioxin-like compounds measured by DR-CALUX® (23 pg CALUX-TEQ/g lipids) were above detection limit in more than 75% of the samples. Age and smoking habits of the mothers, did not influence the cord blood Pb and Cd levels. The organochlorines increased 4 to 9% per year of the mother's age (partial R= 0.05 to 0.22). Mothers had 2.6% less PCBs in cord blood (partial R= 0.02) for each unit increase in pre-pregnancy BMI. Season of delivery, breastfeeding previous children or consumption of local dairy products, were minor determinants. Up to 20% of the variability in organochlorine concentrations was explained by residence area. It was concluded that the place of birth in Flanders is an important determinant of the load of pollutants measured at the start of life. This underlines the validity of human biomonitoring on (relatively) small geographical scale.  相似文献   
73.
The formation of secondary organic aerosol from the gas-phase reaction of catechol (1,2-dihydroxybenzene) with ozone has been studied in two smog chambers. Aerosol production was monitored using a scanning mobility particle sizer and loss of the precursor was determined by gas chromatography and infrared spectroscopy, whilst ozone concentrations were measured using a UV photometric analyzer. The overall organic aerosol yield (Y) was determined as the ratio of the suspended aerosol mass corrected for wall losses (Mo) to the total reacted catechol concentrations, assuming a particle density of 1.4 g cm?3. Analysis of the data clearly shows that Y is a strong function of Mo and that secondary organic aerosol formation can be expressed by a one-product gas–particle partitioning absorption model. The aerosol formation is affected by the initial catechol concentration, which leads to aerosol yields ranging from 17% to 86%. The results of this work are compared to similar studies reported in the literature.  相似文献   
74.
Leaching behaviour of hazardous demolition waste   总被引:1,自引:1,他引:0  
Demolition wastes are generally disposed of in unlined landfills for inert waste. However, demolition wastes are not just inert wastes. Indeed, a small fraction of demolition waste contains components that are hazardous to human health and the environment, e.g., lead-based paint, mercury-contained in fluorescent lamps, treated wood, and asbestos. The objective of this study is to evaluate the release potential of pollutants contained in these hazardous components when they are mixed with inert wastes in unlined landfills. After identification of the different building products which can contain hazardous elements and which can be potentially pollutant in landfill scenario, we performed leaching tests using three different lysimeters: one lysimeter containing only inert wastes and two lysimeters containing inert wastes mixed with hazardous demolition wastes. The leachates from these lysimeters were analysed (heavy metals, chlorides, sulphates fluoride, DOC (Dissolved Organic Carbon), phenol index, and PAH). Finally, we compared concentrations and cumulative releases of elements in leachates with the limits values of European regulation for the acceptance of inert wastes at landfill. Results indicate that limit values are exceeded for some elements. We also performed a percolation column test with only demolition hazardous wastes to evaluate the specific contribution of these wastes in the observed releases.  相似文献   
75.
Over the past 3 decades, indigenous guardian programs (also known as indigenous rangers or watchmen) have emerged as an institution for indigenous governments to engage in collaborative environmental governance. Using a systematic review of peer-reviewed literature for research conducted in Australia, Canada, Aotearoa-New Zealand, and the United States, we sought to characterize the emergence of indigenous guardians in the literature and explore whether guardian approaches are representative of Indigenous approaches to environmental governance. Using a multistep relevance-screening method, we reviewed 83 articles published since 1995, that report on, critique, or comment on Indigenous guardians. Our findings indicated that most articles on the topic were published in the last decade (88%), focused on Australia (65%), and were in a social science discipline (53%). The lead author of the majority of articles was an academic, although only half of the articles included an indigenous scholar or member of an indigenous group or organization as a coauthor. Finally, 11 articles were on research of guardian programs that were locally led and only 5 exemplified indigenous governance, based on 2 well-known community-based monitoring typologies. Our findings indicate that more research is required to understand the implications of current guardian programs for indigenous self-determination, particularly when such programs are embedded in a broader western environmental governance structure.  相似文献   
76.
Some conservation prioritization methods are based on the assumption that conservation needs overwhelm current resources and not all species can be conserved; therefore, a conservation triage scheme (i.e., when the system is overwhelmed, species should be divided into three groups based on likelihood of survival, and efforts should be focused on those species in the group with the best survival prospects and reduced or denied to those in the group with no survival prospects and to those in the group not needing special efforts for their conservation) is necessary to guide resource allocation. We argue that this decision-making strategy is not appropriate because resources are not as limited as often assumed, and it is not evident that there are species that cannot be conserved. Small population size alone, for example, does not doom a species to extinction; plants, reptiles, birds, and mammals offer examples. Although resources dedicated to conserving all threatened species are insufficient at present, the world's economic resources are vast, and greater resources could be dedicated toward species conservation. The political framework for species conservation has improved, with initiatives such as the UN Sustainable Development Goals and other international agreements, funding mechanisms such as The Global Environment Facility, and the rise of many nongovernmental organizations with nimble, rapid-response small grants programs. For a prioritization system to allow no extinctions, zero extinctions must be an explicit goal of the system. Extinction is not inevitable, and should not be acceptable. A goal of no human-induced extinctions is imperative given the irreversibility of species loss.  相似文献   
77.
Sex ratio theory is one of the most controversial topics in evolutionary ecology. Many deviations from an equal production of males and females are reported in the literature, but few patterns appear to hold across species or populations. There is clearly a need to identify fitness effects of sex ratio variation. We studied this aspect in a population of a long-lived seabird, the wandering albatross (Diomedea exulans), using molecular sex-identification techniques. We report that parental traits affect both (1) fledgling traits in a sex-dependent way and (2) chick sex: Sons are overproduced when likely to be large at fledging and, to a lesser extent, daughters are overproduced when likely to be in good body condition at fledging. Because for the same population, a previous study reported that post-fledging survival was positively affected by size in males and by body condition in females, our results suggest that wandering albatrosses manipulate offspring sex to increase post-fledging survival.  相似文献   
78.
As physicochemical properties of the soil highly influence the bioavailable fraction of a particular trace metal, measured metal body burdens in a particular species are often assumed to be more reliable estimators of the contamination of the biota. To test this we compared the Cd, Cu and Zn content of three spiders (generalist predators) and two amphipods (detritivores), co-occurring in seven tidal marshes along the river Schelde, between each other and with the total metal concentrations and the concentrations of four sequential extractions of the soils. Correlations were significant in only one case and significant site x species interactions for all metals demonstrate that factors affecting metal concentration were species and site specific and not solely determined by site specific characteristics. These results emphasize that site and species specific biological factors might be of the utmost importance in determining the contamination of the biota, at least for higher trophic levels. A hypothetical example clarifies these findings.  相似文献   
79.
80.
On Mediterranean calcareous soils, high fire frequency induces soil impoverishment and the development of stable Quercus coccifera garrigues. Organic amendment could increase soil fertility levels, and could alter the vegetation dynamics and the established dominance relationships. In this study, the plant cover evolution is monitored in an amended burnt shrub during two years. Three treatments are studied: control (D0), 50 t ha−1 (D50) and 100 t ha−1 (D100) of fresh co-composted sewage sludge and greenwastes.First, the spreading process leads to the squashing of the vegetation, whose intensity reaches a threshold on D100 and limits the woody species’ recovery after amendment. Consequently, the dominant herb Brachypodium retusum is favoured. On D50, woody species are favoured compared to herbs, probably due to the space colonization strategy of Q. coccifera after squashing. Thus, compost at both rates favours the two dominant resprouter species until they have colonized all the free space created by squashing.Secondly, compost has some fertilizing effects on Rosmarinus officinalis and Ulex parviflorus, that improves their cover on D50. However, compost also increases U. parviflorus’ sensitivity to drought.At the end of the experiment, a third compost effect appears, as seeder cover becomes greater than D0 on D50. After amendment, compost covers rocky stones, which creates a new territory where species with superficial rooting can establish (mulch effect).  相似文献   
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