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191.

A study of social attitudes to urban energy management strategies has been undertaken as part of a research project aiming to develop an energy planning tool for urban planners. The study used a social survey to predict attitudinal responses to proposed engineering solutions, namely load management, energy efficiency and alternative supply options (renewable energy). The principal influence on attitude formation, which emerges from the literature and this study, appears to be socio-economic conditioning.The results indicate that Leicester citizens are open to alternative energy strategies, such as a willingness to pay additional amounts of money for electricity generated from renewable or sustainable sources and the purchase of low energy appliances. Over half the sample surveyed would pay up to 5% extra for an energy-efficient appliance, and a significant minority would pay extra for 'green' energy. In addition, 73% of respondents are sympathetic to Demand-side Management measures such as interruptible tariffs. The use of 'social group' analysis has proved to be a useful and sensitive tool for the market analysis of energy-related behaviour. In this study, a positive relationship between energy-related attitudes and income is revealed.  相似文献   
192.
193.
This article presents the design of a fuzzy decision support system (DSS) for the assessment of alternative strategies proposed for the restoration of Lake Koronia, Greece. Fuzzy estimates for the critical characteristics of the possible strategies, such as feasibility, environmental impact, implementation time, and costs are evaluated and supplied to the fuzzy DSS. Different weighting factors are assigned to the critical characteristics and the proposed strategies are ordered with respect to the system responses. The best strategies are selected and their expected impact on the ecosystem is evaluated with the aid of a fuzzy model of the lake. Sensitivity analysis and simulation results have shown that the proposed fuzzy DSS can serve as a valuable tool for the selection and evaluation of appropriate management actions. Note: This version was published online in June 2005 with the cover date of August 2004.  相似文献   
194.
The development of a model for assessing the impact and interactions of stressors in the ecosystem of Lake Koronia, based on fuzzy inference, is presented in this paper. The proposed fuzzy inference model assesses the synergistic interactions among several significant stressors on fish production. These stressors include industrial pollution, pesticide and nutrient usage due to agricultural activities, and water level decrease due to irrigation works. Apart from the experts knowledge, expressed in a set of fuzzy rules, a number of parameters such as pH, conductivity, biochemical and chemical oxygen demand, and nitrate concentration were used as stressor indicators. The proposed model is capable of simulating the effect of a large variety of environmental conditions, and it can be used as a dynamic tool for ecosystem risk assessment since it produces both qualitative and quantitative results, allowing for comparisons of predictions with on-going observational research and ecosystem monitoring. Its operation was successfully verified for a number of different conditions, ranging from low stressor impact to high stressor impact (where, in fact, the fish production was diminished). Moreover, the proposed fuzzy inference model can be used as a tool for the investigation of the behavior of the aquatic ecosystem under a large number of hypothetical environmental risk scenarios.  相似文献   
195.
Pollutants that exist in anionic species are issues of concern in water treatment. Compared to cationic pollutants, the removal of anionic pollutants by adsorption is more difficult because most adsorbents carry predominantly negative charges in neutral and alkaline environments. In this study, a cross-linked chitosan derivative with quaternary ammonium and magnetic properties(QM-chitosan) was prepared and employed to remove chromium(VI) and phosphorus(V)(Cr(VI) and P(V)) from aqueous environments. The QM-chitosan was characterized by Fourier transform infrared spectrometry(FT-IR),thermogravimetric analysis(TGA), energy dispersive X-ray(SEM-EDX) and zeta potential.Batch experiments show that QM-chitosan can effectively remove Cr(VI) and P(V), and the main mechanism was believed to be electrostatic interaction. A pseudosecond-order model was fitted to describe the kinetic processes of Cr(VI) and P(V) removal. The adsorption isotherms of both Cr(VI) and P(V) on the QM-chitosan were well fitted by the Langmuir isotherm equation. The saturated adsorption capacity of P(V)(2.783 mmol/g) was found to be higher than that of Cr(VI)(2.323 mmol/g), resulting from the size of the H2PO-4ions being smaller than that of the HCr O-4ions. However, the theoretical calculation and experimental results showed that QM-chitosan had a stronger affinity for Cr(VI) than P(V). The adsorption–desorption of the QM-chitosan was evaluated, and high regeneration rates were demonstrated.  相似文献   
196.
Attempts by researchers and policy-makers to address the ‘wicked’ issues which pervade environmental policy usually revolve around attempting – or recommending – both more participatory and transparent, and more systematic and evidence-based, policy-making. Post-normal science (PNS), with its ‘extended peer community’, has emerged as one approach, whilst others focus on procedural reforms of the policy process, particularly on enhancing democratic decision-making. This paper applies a novel analytical framework to a primarily documentary analysis of three cases we argue are wicked—Canadian regulatory review of health products and food, European union (EU) environmental thematic strategies, and United Kingdom (UK) energy and climate change policy. It explores how various responses to wicked issues are implemented, through the ‘lenses’ of PNS and, more generally, ‘democratic and effective decision-making’. It finds such responses are often limited by practical and fundamental barriers relating to handling of uncertainty, issue framing, participation, power, politics, and attitude to evidence. We draw conclusions about future research on PNS, particularly the need to more clearly relate theory to different strands of literature on the evidence–policy-making relationship, and to continue empirical testing.  相似文献   
197.
Cationic hydrogel with magnetic property was synthesized via radical polymerization and its removal capacity of chromate from contaminated water was found to be 200 mg/g. Using Fourier transform infrared spectroscopy (FT-IR) study, the mechanism of chromate removal by hydrogel was found to be non-specific adsorption, mainly due to ion exchange, as evidenced by the positively charged functional group, trimethyl ammonium –N+(CH3)3; in the monomer. Verifications were accordingly determined by testing different oxyanion adsorption onto the hydrogel. The results of the chromate adsorption experiments illustrated that the amount of chromate adsorbed was nearly equal to that of the chloride released from the hydrogel, which is part of the evidence for ion exchange. Single and multi-oxyanion adsorption experiments were also performed, and it was demonstrated that ion removal was species independent, but charge dependent, another characteristic of the ion exchange process. It was found that the same Langmuir model can be applied to best fit the findings of single and multi-oxyanion adsorption, which further indicates the mechanism of chromate removal is attributed to ion exchange. In view of the above, the background anions compete for adsorption sites with chromate, evidenced by inhibitive chromate removal in the presence of background electrolytes in the batch studies, further echoing the ion exchange mechanism.  相似文献   
198.
/ The species richness of shoreline vegetation of unregulated lakes in Nova Scotia, Canada, is known to increase as a function of catchment area, a topographic variable governing water level fluctuations. Predictions based on catchment area however, fail to account for richness patterns at the margins of lakes enlarged by dams. Here, we compare the vegetation and hydrological regimes of regulated and unregulated systems. Hydrological regimes of regulated systems deviated from natural systems of similar catchment area by being either hypovariable or hypervariable for both within-year and among-year fluctuations in water level. Plant communities of dammed systems were less diverse, contained more exotic species, and were, with one exception, devoid of rare shoreline herbs. Data from "recovering," or previously dammed systems indicated that shoreline communities can be restored upon return of the appropriate hydrological regime. Using observed within-year and among-year water level fluctuation data, we propose a general model for the maintenance or restoration of diverse herbaceous wetlands on shorelines of temperate lakes or reservoirs. Managers can manipulate the within-year water level variation within prescribed limits (1-2 m), while ensuring that among-year variation (SD of summer levels) is less than 25% of within-year variation. This preliminary model is based on data from low-fertility, temperate lakes in river systems. To calibrate the model, plant community data from other regions are needed, as are long-term water-level data for unregulated lakes, data which are essential but largely lacking in many areas.KEY WORDS: Catchment area; Regulated lakes; Shoreline restoration; Rare plants; Exotic plants; Diversity  相似文献   
199.
Environmental Science and Pollution Research - This paper reports on the seasonal and species comparison of hepatic nodular alterations in two indicator fish species from the hyper-eutrophic...  相似文献   
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