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41.
42.
Activated (AC-PW) and non-activated (C-PW) carbonaceous materials were prepared from the Brazilian-pine fruit shell (Araucaria angustifolia) and tested as adsorbents for the removal of reactive orange 16 dye (RO-16) from aqueous effluents. The effects of shaking time, adsorbent dosage and pH on the adsorption capacity were studied. RO-16 uptake was favorable at pH values ranging from 2.0 to 3.0 and from 2.0 to 7.0 for C-PW and AC-PW, respectively. The contact time required to obtain the equilibrium using C-PW and AC-PW as adsorbents was 5 and 4 h at 298 K, respectively. The fractionary-order kinetic model provided the best fit to experimental data compared with other models. Equilibrium data were better fit to the Sips isotherm model using C-PW and AC-PW as adsorbents. The enthalpy and entropy of adsorption of RO-16 were obtained from adsorption experiments ranging from 298 to 323 K.  相似文献   
43.
Increased emphasis on reduction of mercury emissions from coal fired electric power plants has resulted in environmental regulations that may in the future require application of activated carbons as mercury sorbents for mercury removal. At the same time, the quantity of poultry manure generated each year is large and technologies that take advantage of the material should be explored. The purpose of the work was to obtain preliminary data to investigate if activated chars made from different poultry manures could adsorb mercury from simulated flue gas. In laboratory experiments, activated chars made from chicken cake and litter removed mercury from the gas as well as a commercial alternative. It was also found that acid-washing these chars after activation may improve pore structure but does not influence the mercury removal efficiency. Activated chars were also made from turkey cake and litter. These raw materials produced activated chars with similar pore structure as those made from chicken manure, but they did not adsorb mercury as well. Acid-washing the turkey manure-based chars improved their performance, but this step would add to the cost of production. Preliminary evaluations suggest that unwashed activated chars may cost as little as $0.95/kg to produce.  相似文献   
44.
Agriculture is the major land use at a global scale. In addition to food production, multifunctionality of landscapes, including values and ecosystem services like biodiversity, recreation and culture, is now focus for management. This study explores how a scenario approach, involving different stakeholders, may help to improve landscape management for biodiversity conservation. Local farmers and executives at the County Administrative Board were invited to discuss rural development and conditions for farmland biodiversity in two Swedish landscapes. The potential biodiversity for three future land use scenarios for the two landscapes was discussed: nature conservation, outdoor recreation and energy production, and compared with current and historical landscapes in each region.Analyses of habitat areas, connectedness and landscape diversity suggested that the energy and recreation scenarios had a negative impact on farmland biodiversity, whereas the nature conservation scenario, the current and historically reconstructed landscapes had a higher potential for biodiversity. The farmers appreciated the nature conservation scenario, but also the energy production scenario and they highlighted the need of increased subsidies for management of biodiversity. The farmers in the high production area were less interested in nature quality per se. The executives had similar opinions as the farmers, but disagreed on the advantages with energy production, as this would be in conflict with the high biodiversity and recreational values. The local physical and socio-economical conditions differ between landscapes and potentially shaped the stakeholders emotional attachment to the local environment, their opinions and decisions on how to manage the land. We stress the importance of incorporating local knowledge, visions and regional prerequisites for different land uses in conservation, since site and landscape specific planning for biodiversity together with a flexible subsidy system are necessary to reach the conservation goals within EU.  相似文献   
45.
The European Union Water Framework Directive (WFD) requires Member States to set water quality objectives and identify cost-effective mitigation measures to achieve "good status" in all waters. However, costs and effectiveness of measures vary both within and between catchments, depending on factors such as land use and topography. The aim of this study was to develop a cost-effectiveness analysis framework for integrating estimates of phosphorus (P) losses from land-based sources, potential abatement using riparian buffers, and the economic implications of buffers. Estimates of field-by-field P exports and routing were based on crop risk and field slope classes. Buffer P trapping efficiencies were based on literature metadata analysis. Costs of placing buffers were based on foregone farm gross margins. An integrated optimization model of cost minimization was developed and solved for different P reduction targets to the Rescobie Loch catchment in eastern Scotland. A target mean annual P load reduction of 376 kg to the loch to achieve good status was identified. Assuming all the riparian fields initially have the 2-m buffer strip required by the General Binding Rules (part of the WFD in Scotland), the model gave good predictions of P loads (345-481 kg P). The modeling results show that riparian buffers alone cannot achieve the required P load reduction (up to 54% P can be removed). In the medium P input scenario, average costs vary from £38 to £176 kg P at 10% and 54% P reduction, respectively. The framework demonstrates a useful tool for exploring cost-effective targeting of environmental measures.  相似文献   
46.
Environmental Quality Perception (EQP) is an important construct used to help to understand the relationship between people and the hospital environment. From a patient-centered care perspective, it is important that hospital design take into account the patients' (and other users') point of view. This paper presents the adaptation and validation of a measure of hospital EQP, the Perceived Hospital Environment Quality Indicators (PHEQIs; Fornara, Bonaiuto, & Bonnes, 2006), and seeks to confirm the factor structure of this construct in a different cultural context. Three scales, two focusing on physical environments and one evaluating the social environment, were completed by 562 users of four orthopedic units in Portuguese hospitals, two older and two recently built or renovated. To assess criterion validity, hospital physical environments were also objectively evaluated by two architects. Using a confirmatory factor analysis the three validation procedures produced acceptable fit indices in the final measurement models. Overall reliability values were satisfactory, as was the evidence for criterion validity. PHEQIs scales and factors correlated with global evaluation of the environment, supporting concurrent criterion validity; and predictive criterion validity was demonstrated given that users of older and newer hospitals differed significantly on the perception of quality of hospital EQP, and that high congruence between users' and experts' evaluations was found. Discriminant construct validity was supported, and some difficulties in showing convergent validity are discussed in terms of item formulation adequacy. Implications for research and practice are described.  相似文献   
47.
The Festival described in this article won the Golden Ball Award for education of the Italian Academy of Lincei. Dr Maria Luisa Cohen, the author, was honoured with the Tree of Learning Award for 1988, by the Commission on Education and Training of the IUCN, for her services to environmental education and her promotion and participation in the Festival.  相似文献   
48.
This work highlights the evolution of flood disasters and their impacts upon environmental and socioeconomic aspects both worldwide and in Small Island Developing States (SIDS) in particular. For our research, we reviewed the stress factors affecting flood disasters and performed surveys of two focus groups in Funchal municipality on Madeira Island (Portugal). Our research identifies the main causes of the serious impacts that flash floods can have on Funchal city. These include:
  • The occupation of floodplain areas,
  • Canalization of water courses,
  • Erosion and transport of soil from upstream hillslopes due to deforestation, and
  • Intensive precipitation of long duration.
  相似文献   
49.
In view of the Brazilian Ten‐Year Energy Expansion Plan 2021, this article presents a discussion on environmental flow (e‐flow). The authors analyze the literature to show the evolution of publications concerning e‐flow releases from the perspective of ecosystems services preservation considering results from different case studies from throughout the world. Finally, two main recommendations are drawn regarding e‐flow are: (1) performing a holistic approach to e‐flow planning, including hydrological, hydraulic, water quality, habitat, and riparian zone considerations; and (2) installing in new structures adequate bottom outlets to allow a range of adjustable e‐flow from reservoir dams to reproduce natural flow variations.  相似文献   
50.
Brazil produces approximately 242,000 t of waste per day, 76% of it being dumped outdoors and only 0.9% recycled, including composting, which is an alternative still little known in Brazil. In search of a better destination for residues produced by domestic activities, composting stands as a feasible alternative. Organic compost from waste may be used for various purposes, among which are soil recovery, commercial production, pastures, lawns and reforestry and agriculture. However, the quality of the compost determines the growth and the development of plants. The effect of compost made from urban waste on corn plant (Zea mays L.) growth was investigated. Two types of compost were used: the selected compost (SC), produced from organic waste selectively collected; and the non-selected compost (NSC), taken from a 15-year-old cell from the Canabrava land-fill, located in Salvador, Bahia, Brazil (altitude 51 m, 12°22′–13°08′S, 38°08′–38°47′W). Corn was seeded in polyethylene pots, with soil-compost mixing substrate in the proportion of 0, 15, 30, 45 and 60 t ha−1 equivalent doses. Chemical analyses of the compost and growth properties of the plant like chlorophyll content; height and stem diameter; aerial and radicular dry biomasses, were used to evaluate compost quality. Plants cultivated with SC presented a superior gain, being of 52.5% in stem diameter, 71.1 and 81.2% in root and stem biomasses, respectively. Chlorophyl content alterations were observed in plants from treatments using 30 t compost ha−1 dose onwards. Conventional and multivariate statistical methods were used to evaluate these results. The beneficial action of organic compost in plant growth was confirmed with this research.  相似文献   
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