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81.
If sustainability science is to mature as a discipline, it will be important for practitioners to discuss and eventually agree upon the fundamentals of the paradigm on which the new discipline is based. Since sustainability is fundamentally a normative assertion about tradeoffs among values, how society chooses the specifics among these tradeoffs is central to the sustainability problem. Whose values should count in making social decisions and how should the multiplicity of values that exist be known and used in that decision process? Given the vast spatial domains and temporal domains at work in the sustainability problem, we need some means of reconciling the inevitably divergent choices depending on whose values we count, how we know what those values are, and how we count them in making social decisions. We propose an approach to dealing with these questions based on Rawls (A theory of justice. Belknap Press, Cambridge, 1971) and explore the problems inherent in a social choice theory for sustainability science.  相似文献   
82.
Between 2000 and 2007 pooled muscle tissue samples of the European eel (Anguilla anguilla) from 48 sites in Flanders (Belgium) were analysed for 30 polychlorinated biphenyl (PCB) congeners. There was a large variation between individual sites (range 11-7752 ng/g wet weight (ww) for the sum of the ICES 7 PCBs), eels from the River Meuse basin (mean 1545 ng/g ww) being considerably more polluted than those from the River Scheldt (615) and IJzer (61) basins. Overall, PCB 153, PCB 138 and PCB 180 were the most prominent congeners, however PCB patterns varied between the monitored locations. Analysis of the weight percentage of congeners demonstrates obvious differences in PCB composition between sites, indicating differential sources of pollution. Due to the variation in patterns, atmospheric fallout does not seem to be the main source of the PCB spread, but instead both local and upstream sources linked to industrial activities seem to be the main cause for PCB presence in Flanders. Considering the levels of the Sum 7 PCBs, eels are not compliant with the Belgian legal limits for consumption (75 ng/g ww) in 71% of the sites. Regular consumption of eels from polluted sites leads to a considerable excess of the WHO Acceptable Daily Intake value. Consumption of wild eels should by all means be prevented, as it presents risks for human health, especially for local anglers consuming their catch.  相似文献   
83.
Three studies test whether the southern route preference, which describes the tendency for route planners to disproportionately select south- rather than north-going routes, can be attributed to regional elevation patterns; specifically, we ask whether this effect replicates in three topographically disparate international regions, one of which is characterized by higher elevations to the north and lower to the south (Padua, Italy), and two characterized by higher elevations to the south and lower to the north (Enschede, Netherlands; Sofia, Bulgaria). In all cases, we found strong evidence that route planners disproportionately select south- rather than north-going routes at rates exceeding chance. We conclude that the southern route preference is driven by strong associations between canonical direction and perceived effort of route traversal; these effects are somewhat perplexing given that such associations are not founded in the reality of physical space.  相似文献   
84.
This paper aims to understand the role of organizational routines as possible barriers to the mainstreaming of climate adaptation at the implementation stage. While the mainstreaming of climate adaptation into policy documents is relatively easy, the implementation of these policies seems to be more problematic. Barriers to climate adaptation often occur during this stage as the implementation of the policies is generally undertaken by other actors than the policy-makers. These actors act based on organizational routines. As organizational routines aim to provide stability, they tend to be reaffirmative. Reorganizing the resources and practices of these actors to initiate mainstreaming then proves difficult. Consequently, the routines could prevent change that might be necessary to address new policy objectives such as climate adaptation. An analytical framework consisting of four self-reinforcing mechanisms is used to understand and explain why and how organizational routines can hamper the mainstreaming of climate adaptation during implementation. A case study is used to illustrate organizational routines as possible barriers. The paper concludes by stating that to optimize the possibilities of mainstreaming climate adaptation, a change in routines is necessary. In order to stimulate change in organizational routines, the focus should be on reflecting on existing routines, legitimacy building and learning.  相似文献   
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Many organisms show differences between males and females in growth rate and crucial life history parameters, such as longevity. Considering this, we may expect levels of toxic metabolic by-products of the respiratory chain, such as reactive oxygen species (ROS), to vary with age and sex. Here, we analyse ROS levels in female Australian painted dragon lizards (Ctenophorus pictus) and their offspring using fluorescent probes and flow cytometry. Basal level of four ROS species (singlet oxygen, peroxynitrite, superoxide and H2O2) measured with a combined marker, and superoxide measured specifically, varied significantly among families but not between the sexes. When blood cells from offspring were chemically encouraged to accelerate the electron transport chain by mitochondrial uncoupling, net superoxide levels were three times higher in daughters than sons (resulting in levels outside of the normal ROS range) and varied among mothers depending on offspring sex (significant interaction between maternal identity and offspring sex). In offspring, there were depressive effects on ROS of size-controlled relative clutch size, which relies directly on circulating levels of vitellogenin, a confirmed antioxidant in some species. Thus, levels of reactive oxygen species varies among females, offspring and in relation to reproductive investment in a manner that makes its regulatory processes likely targets of selection.  相似文献   
88.
The implementation of large-scale programmes for environment and development presents two main challenges: the tensions between both goals and the disconnect across policy levels. To contribute to overcoming these challenges, we assess a national multi-partnership programme for poverty alleviation and wetland restoration in South Africa: Working for Wetlands. We analyse this innovative polycentric programme at the macro and micro levels. At the national level, we assess the policy development and implementation model. At the local level, we analyse its impact on livelihoods and on opinions about development and the environment at a specific location. We use data from in-depth interviews across scales, household surveys (n = 47) and focus group discussions. The strengths of this programme can inform more effective design of further large-scale environment and development policies. However, critical issues originated at the national scale are likely to hinder the permanence of improvements at the micro level.  相似文献   
89.
This paper includes the findings of MMI Thornton Tomasetti’s investigation into the measurement of resilience within infrastructure using systems thinking and focussed on value delivery. This paper provides a review of current practise across critical infrastructure sectors, based on a series of interviews undertaken with stakeholders from various UK infrastructure organisations. Gaps and opportunities were identified and an outline for a value-based approach to diagnosing, measuring and building resilience suggested. The performance of critical infrastructure sectors was also comparatively assessed using the suggested approach value metrics.  相似文献   
90.
Air pollution has a deleterious impact on public health and the environment. There is few knowledge on the effect of air pollution on terrestrial microbial communities, despite the major role of microbes in ecosystems. Here, we designed an in situ trial ecosystem to assess the impact of moderate atmospheric pollution, below World Health Organization (WHO) thresholds, on an indigenous microbial communities, including bacteria, fungi, ciliates, algae, cyanobacteria, testate amoebae, rotifers and nematodes, extracted from terrestrial bryophytes. These micro-ecosystems were placed at a rural, an urban and an industrial site in France and were thus exposed to various levels of nitrogen dioxide (NO2), from 6.6–67.9 μg·m?3, and particulate matter, from 0.7–7.9 μg·m?3. Microbial analysis was performed by microscopy. We determined atmospheric temperature, relative humidity and particulate matter with diameter lower than 10 µm (PM10), Cu, Cr, Fe, Ni, Pb, Zn in PM10, and (NO2). Results show a significant impact of chronic moderate exposure to NO2 and copper Cu-associated particulate matter on the global microbial network complexity. This is evidenced by a loss of about 40 % of microbial co-occurrence links during incubation. Most lost microbial links are ecologically positive links. Moreover, most changes in community co-occurrence networks are related to testate amoebae, a major top predator of microbes. Overall, our findings demonstrate that air pollution can have strong deleterious effects on microbial interactions, even at levels below WHO thresholds.  相似文献   
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