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991.
Stakeholder theory, originally introduced in 1984 by philosopher Edward Freeman, is among the most influential theories today addressing the complex interplay of societal actors. It underwent several transformations and expansions, but the original Freeman model as well as the latest approaches places the corporation at the center positioning the theory as management driven. In this article—from a sustainability science perspective—we argue that sustainability could also be considered as the center, around which societal actors are grouped, because everyone, individuals as well as stakeholders, have a stake in a ‘common future’ that is built on the transformative concept of sustainability. Next to this shift of perspective from corporation to sustainability at the center, we advance the concept of sustainability stakeholders with the new paradigm of the digital age we (are about to) live in: the proposed sustainability-centered stakeholder theory is developed to incorporate novel parameters as brought about by digitalization (such as big data, real-time transparency, algorithmic correlations, predictive analytics, or changing privacy standards). Hence, we classify the stakeholders of sustainability according to their roles as “big data stakeholders:” collectors, generators, and utilizers of big data. This digital sustainability stakeholder model operationalizes the complex interplay between stakeholders focused on their ‘stake’ in sustainability and a common future and illustrates their roles in the digital age. Thus, it offers a normative framework to analyze stakeholders’ responsibility to contribute to, advance, promote, and achieve sustainability.  相似文献   
992.
Regional Environmental Change - Multi-stakeholder perceptions of landscape changes are increasingly recognized as essential inputs to discussions on future landscape developments, particularly when...  相似文献   
993.
Regional Environmental Change - Plausible scenarios of future land use derived from model projections may differ substantially from what is actually desired by society, and identifying such...  相似文献   
994.
Using the GAINS (Greenhouse Gas–Air Pollution Interactions and Synergies) model, we derived Annex I marginal abatement cost curves for the years 2020 and 2030 for three World Energy Outlook baseline scenarios (2007–2009) of the International Energy Agency. These cost curves are presented by country, by greenhouse gas and by sector. They are available for further inter-country comparisons in the GAINS Mitigation Efforts Calculator—a free online tool. We illustrate the influence of the baseline scenario on the shape of mitigation cost curves, and identify key low cost options as well as no-regret priority investment areas for the years 2010–2030. Finally, we show the co-effect of GHG mitigation on the emissions of local air pollutants and argue that these co-benefits offer strong local incentives for mitigation.  相似文献   
995.
Environmental Science and Pollution Research - A continuous flow filtration system was designed to identify and quantify the removal mechanisms of Cyanobacteria (Microcystis aeruginosa) by...  相似文献   
996.
The important challenge for effective management of wastewater sludge materials in an environmentally and economically acceptable way can be addressed through pyrolytic conversion of the sludge to biochar and agricultural applications of the biochar. The aim of this work is to investigate the influence of pyrolysis temperature on production of wastewater sludge biochar and evaluate the properties required for agronomic applications. Wastewater sludge collected from an urban wastewater treatment plant was pyrolysed in a laboratory scale reactor. It was found that by increasing the pyrolysis temperature (over the range from 300 °C to 700 °C) the yield of biochar decreased. Biochar produced at low temperature was acidic whereas at high temperature it was alkaline in nature. The concentration of nitrogen was found to decrease while micronutrients increased with increasing temperature. Concentrations of trace metals present in wastewater sludge varied with temperature and were found to primarily enriched in the biochar.  相似文献   
997.
998.
Abstract: We investigated the persistence of three medium-sized (2–9 kg), rare forest mammals in the fragmented mist-belt Podocarpus forests of the midlands of KwaZulu-Natal Province, South Africa. We recorded patch occupancy of blue duiker (   Philantomba monticola ), tree hyrax (   Dendrohyrax arboreus ), and samango monkey ( Cercopithecus mitis labiatus ) in 199 forest patches. Their rarity is ascribed to the fragmentation and destruction of their forest habitat. Incidence functions, derived from presence and absence data, were formulated as generalized linear models, and environmental effects were included in the fitted logistic models. The small and mostly solitary hyrax and duiker persisted in smaller patches than the large and social monkey. Although this result follows expectations based on relative home-range sizes of each species, the incidence probability of the samango monkey was invariant with increasing isolation, whereas a gradual decrease with increasing isolation was observed for the hyrax and duiker. Group dynamics may inhibit dispersal and increase the isolation effect in social species such as samango monkeys. A mainland-island metapopulation model adequately describes patterns of patch occupancy by the hyrax and duiker, but the monkeys' poor dispersal ability and obvious area-dependent extirpation suggest that they exist in transient, nonequilibrium (declining) metapopulations. Through identification of large forest patches for careful protection and management, the survival of all three species—especially the monkey—could be prolonged. Because no functional metapopulation may exist for the monkey, however, this is an emergency measure. For the duiker and hyrax, larger patches should form part of a network of smaller and closer patches in a natural matrix.  相似文献   
999.
Continuing evidence of the feminising effects of xenoestrogens on a range of wildlife species increases the need to assess the human health risk of these estrogen mimics. We have estimated the exposure of New Zealand males, females and young men to a range of naturally occurring and synthetic xenoestrogens found in food. Only estrogenic compounds that act by interaction with the estrogen receptor have been included. Theoretical plasma estrogen activity levels were derived from estrogen exposure estimates and estrogenic potency data. Theoretical plasma levels were compared with published data for specific xenoestrogens. There was surprisingly close agreement. Xenoestrogenicity from dietary intake was almost equally attributed to naturally occurring and synthetic xenoestrogens. Relative contributions for a male, for example were isoflavones (genistein and daidzein) (36%) and bisphenol A (34%) with smaller contributions from alkyl phenols (18%) and the flavonoids (phloretin and kaempferol) (12%). It is suggested that dietary xenoestrogens might have a pharmacological effect on New Zealand males and postmenopausal women, but are unlikely to be significant for pre-menopausal women.  相似文献   
1000.
Wetland environmental characteristics are examined to determine their spatial and temporal relationships. Two very different Oregon freshwater wetlands provided a range of wetland types. Results are evaluated to determine the possible use of environmental characteristics in defining wetlands and their boundaries. Representative physical, hydrological, and edaphic properties were periodically measured in microplots along upland/wetland transects. A multivariate approach is stressed in the data analysis; correlation, cluster analysis, and principal components analyses were used. The results indicate the environmental characteristics change in a quantifiable manner both spatially and temporally. The controlling mechanism is moisture, spatially in terms of the upland/wetland transect and temporally with respect to seasonal response. These changes do not correlate well with vegetation. Several hypotheses are offered as an explanation. Correlation within environmental characteristics is variable but definite patterns are discernible. These data suggest both single and combinations of environmental characteristics that could serve as keys in wetland identification and boundary determination. However, before extensive use is made of this information additional long-term monitoring of wetland environmental characteristics will be required.  相似文献   
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