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51.
Environment, Development and Sustainability - Our society faces mounting pressure regarding the necessity of green consumption as issues related to the environment will likely become a severe...  相似文献   
52.
The main achievements of the debates on deliberative democracy and democratised science are investigated in order to analyse the reasons, meanings and prospects for a democratisation of global environmental policy. A deliberative systems approach, which emphasises the need to explore how processes in societal spheres interact to shape the deliberative qualities of the system as a whole, is adopted. Although science plays a key role in this, its potential to enhance deliberative capacity has hardly been addressed in deliberative theories. The democratisation of science has potential to contribute to the democratisation of global environmental policy, in that it also shapes the potential of deliberative arrangements in the policy sphere. Deliberative arrangements within the policy sphere may stimulate the democratisation of science to different degrees.  相似文献   
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Journal of Polymers and the Environment - Biocompatible chitosan/PVP blends of different weight ratios were prepared by the solution casting method. The blends were characterized for morphology,...  相似文献   
55.
International Union for Conservation of Nature (IUCN) Red List assessments rely on published data and expert inputs, and biases can be introduced where underlying definitions and concepts are ambiguous. Consideration of climate change threat is no exception, and recently numerous approaches to assessing the threat of climate change to species have been developed. We explored IUCN Red List assessments of amphibians and birds to determine whether species listed as threatened by climate change display distinct patterns in terms of habitat occupied and additional nonclimatic threats faced. We compared IUCN Red List data with a published data set of species’ biological and ecological traits believed to infer high vulnerability to climate change and determined whether distributions of climate change‐threatened species on the IUCN Red List concur with those of climate change‐threatened species identified with the trait‐based approach and whether species possessing these traits are more likely to have climate change listed as a threat on the IUCN Red List. Species in some ecosystems (e.g., grassland, shrubland) and subject to particular threats (e.g., invasive species) were more likely to have climate change as a listed threat. Geographical patterns of climate change‐threatened amphibians and birds on the IUCN Red List were incongruent with patterns of global species richness and patterns identified using trait‐based approaches. Certain traits were linked to increases or decreases in the likelihood of a species being threatened by climate change. Broad temperature tolerance of a species was consistently related to an increased likelihood of climate change threat, indicating counterintuitive relationships in IUCN assessments. To improve the robustness of species assessments of the vulnerability or extinction risk associated with climate change, we suggest IUCN adopt a more cohesive approach whereby specific traits highlighted by our results are considered in Red List assessments. To achieve this and to strengthen the climate change‐vulnerability assessments approach, it is necessary to identify and implement logical avenues for further research into traits that make species vulnerable to climate change (including population‐level threats).  相似文献   
56.
A survey was conducted in Uttar Pradesh to enlist the available exotic fish species in culture. The culture and feeding details of unofficially introduced Clarias gariepinus was collected from 419 ponds existing in rural areas of 23 districts of Uttar Pradesh. The data indicated that 32% ponds were culturing exotic fishes of which 79% cases are of monoculture of exotic African catfish. Feeding analysis of these exotic African catfish revealed that 7% cases subsist on natural pond feed while 29% cases are fed on slaughter house waste. In 32% cases of the exotic magur monoculture, chicken waste was given whereas 11% cases were recorded with fish waste feeding. The possible threats and environmental risks of such unauthorised and indiscreminate culture of exotic magur has been discussed in this paper.  相似文献   
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Fluoride concentration in bones and differential haemotological characteristics (RBC, haemoglobin, haematocrit, mean corpusclar haemoglobin and mean corpuscular volume) were measured in amphibians, Bufo melanostictus, collected from fluoride-contaminated and -uncontaminated areas. The average haemoglobin content, total RBC count and haematocrit (%) in blood samples were found to be significantly reduced, while mean corpuscular concentration and volume were significantly elevated in individuals from the contaminated area in comparison to those from the uncontaminated area. Fluoride concentration was approximately 11 times greater in the bones of toads from the contaminated area.  相似文献   
59.
In standardized ecotoxicological testing chemicals are investigated under optimal conditions for the test organisms despite the fact that environmental factors such as predation pressure and food availability are important parameters regulating natural populations. Food limitation and predator presence can induce shifts in life-history traits in various Daphnia species, especially trade-offs in reproductive biomass allocation. These adaptive responses are thought to ensure survival of the population in a highly variable environment. A xenobiotic dispersant (used in textile dyeing processes) also shifted the biomass allocation of Daphnia magna. To assess whether the dispersant could hinder D. magna adaptation to varying environmental conditions, we conducted experiments with food level and presence of Chaoborus larvae as environmental factors and simultaneous exposure to the dispersant. At low food level and in presence of the predator, D. magna produced fewer but larger sized neonates, regardless of dispersant exposure. The dispersant shifted biomass allocation towards more but smaller sized offspring in all experiments. However, the adaptive response to the environmental factors and the dispersant effect cancelled each other out in that they induced independently from each other opposite shifts in biomass allocation. In summary, the dispersant exposure resulted not in an inhibition of the adaptive response but in a reduction of the value of the response. Our study with this model substance demonstrates that xenobiotics can affect the adaptation of organisms to environmental stress which can result in effects likely to be overlooked in standardized testing.  相似文献   
60.
Subbiah D  Kala S  Mishra AK 《Chemosphere》2005,61(11):1580-1586
The fluorescence spectroscopic behavior of bromadiolone (anticoagulant rodenticide), a substituted 4-hydroxycoumarin derivative, was investigated in water and in organized media like micelles and cyclodextrins. A detailed study on various photophysical parameters like fluorescence intensity (IF), quantum yield (), lifetime (τ) and steady state fluorescence anisotropy (r) of bromadiolone in aqueous and in organized media was carried out. Bromadiolone in aqueous solution was observed to be in an aggregated state, thereby showing weak emission due to self-quenching. Marked enhancement of fluorescence intensity was observed in organized media like micelles and β-cyclodextrin. A preliminary investigation has been done to find out whether this enhancement of fluorescence can be used to develop a sensitive analytical method for determination of bromadialone in aqueous media. A linear relationship between the fluorescence intensity and concentration of bromadiolone was observed in the range of 0.15–7.9 μg ml−1 in cetyltrimethylammonium bromide (CTAB) and 0.5–26.4 μg ml−1 in β-cyclodextrin medium. The lower detection limit was found to be 37 ng ml−1 in presence of CTAB and 23 ng ml−1 in β-cyclodextrin. Comparison with 4-hydroxycoumarin, an unsubstituted analogue, was made.  相似文献   
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