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431.
Al-Mohannadi HI  Hunt CO  Wood AP 《Ambio》2003,32(5):362-366
Qatar has serious water resource problems, following rapid socioeconomic development and massive population increase. Municipal water provision depends on costly and unsustainable desalination. There is little regulation. Native Qataris do not pay a water tariff and migrants pay a subsidized price--approximately one third of the cost of production--so there is little awareness of the true cost of water and use is profligate. This paper discusses trends in water use and identifies issues underlying sustainable water use in Qatar. A questionnaire of respondents chosen to represent Qatari social groups measured awareness and attitudes to water. The results show that previous efforts to control water demand in Qatar, using awareness campaigns, legal restrictions and tariffs, have been ineffectual. The questionnaire evaluated reactions to possible measures to limit uses by raising awareness, using legal restrictions and raising tariffs. From this, a number of policy changes can be suggested, to bring Qatar's water industry towards sustainability.  相似文献   
432.
This analysis presents results based on a five-yearstudy recently supported by the Louisiana Departmentof Transportation and Development (DOTD) in which theacute toxicity, fate and effect of herbicide mixtureson human health and the environment were assessed. Three sites were routinely sprayed by DOTD to killweeds along the roadsides. Two herbicide mixtures wereused, 2,4-D and Roundup, and Garlon 3A and Roundup.Water, vegetation, soil and sediment samples werecollected quarterly for three years and were analyzedfor pesticide content to study the fate and impact ofherbicides in the environment. Results indicate acorrelation between soil type, herbicide type, andpersistence of the herbicide in the environment. Usingthe correlations found in these data, spatial analysisidentified areas where herbicide use may potentiallycause surface water and sediment contamination, basedon soil composition/properties, type of herbicideapplied, and proximity of water bodies to sprayed areas.  相似文献   
433.
434.
Products of a power plant flue gas desulfurization scrubber are discharged into a pond as sludge consisting of calcite (initial delta13C 3.2-3.8 per thousand), gypsum (initial delta34S 7.6-8.6 per thousand), and aqueous solution. Reducing conditions exist below a boundary that appears to move vertically as a function of changes in pond water level. Under reducing conditions, bacteria partially reduce aqueous sulfate to low-delta34S sulfide, consuming organic carbon and generating low-delta13C bicarbonate. Under oxidizing conditions, sulfide is converted to sulfate, leading to calcite dissolution, gypsum precipitation, and isotopic re-equilibration of remaining calcite with dissolved bicarbonate near the pond surface. The gypsum has delta34S near 6 per thousand, and calcite has delta13C as low as -1.7 per thousand; the changes from initial values correspond to predictions based on isotopic balance and reaction stoichiometry. The pond largely contains the products of bacterial reduction. After the pond is abandoned, these products may adversely affect attempts to revegetate the site. Future bacterial reduction may be best controlled by dewatering and limiting the supply of organic matter in percolating surface water.  相似文献   
435.
Gas-cooled nuclear power plants in the UK release sulphur-35 during their routine operation. The gas is in the form of COS which can be readily assimilated by vegetation. It is therefore necessary to be able to model the uptake of such releases in order to quantify any potential contamination of the food chain. To develop such models experimental data are required. A series of experiments was undertaken to determine the rate of deposition, the partition and subsequent loss of sulphur-35 in crops exposed to CO(35)S. The mass normalised deposition rate was similar for the range of crops tested, while the partition of the (35)S paralleled the growth of crop components. There was no significant loss of radioactivity other than that expected from radioactive decay.  相似文献   
436.
This article introduces the concept of ISO 14001 registration, outlines related assessment processes, and reviews the drivers behind developing an ISO-14001-concordant environmental management system (EMS) and seeking third party registration of that EMS. It focuses on registration strategies for larger organizations and considerations in choosing a registrar, including: auditor qualifications, standards for the conduct of EMS audits, and some issues for audit and registration service providers. The authors conclude that it is beneficial to pursue an ISO-14001-concordant EMS and that the value of the system can be enhanced through registration. However, some thought should be given to choosing the appropriate registrar, in particular to their EMS and audit approaches and to the qualifications of their audit team. Service providers are also cautioned to remember that ISO 14001 is not the same as ISO 9000, and that the registrar's standard of care in the discharge of their work should reflect that. © 1998 John Wiley & Sons, Inc.  相似文献   
437.
Nant Gwydyr, a tributary of the River Conwy in North Wales, has been affected by metal wastes, from a lead and zinc mine, Parc Mine, through contaminated mine drainage waters and episodal erosion of an unstable tailings heap. From 1954 when the mining operation was discontinued to 1978 when a reclamation programme aimed to stabilise the tailings was accomplished, 13 000 tonnes of metalliferous spoil, containing 43 tonne Pb, 104 tonne Zn, and 1 tonne Cd was eroded from the main tailings dam. Dispersal and redeposition during flood events caused extensive pollution of the agricultural land of the flood plain. Analysis of the present water quality of the Nant Gwydyr, 14 years after the stabilisation work, shows that although there has been a marked improvement and no particulate matter is released, the Nant Gwydyr is still a polluted stream. Under normal discharge conditions, it contributes approximately 1 tonne of Zn, 0.2 tonne of Pb and 0.05 tonne of Cd per year to the River Conwy. Most of this originates from water issuing from the mine adit which has been impossible to control. There is still, however, a major contribution by the leachate from the tailings heap, because the stabilisation method used does not prevent this. The control of pollution in mine drainage is discussed.  相似文献   
438.
439.
Various cleaner production (CP) audits have been conducted in the South African metal finishing industry. These studies have been successful in effecting changes to the general status of the local metal finishing industry. In this paper, the initiatives undertaken by a Danish government sponsored project are detailed. The project included the conducting of in-plant assessments, using a tailor-made tool for CP benchmarking. Details on this tool's operations and typical results are presented. Typical assessments indicated potential water savings of 78%, with chemical savings of approximately 30%. The plant modifications undertaken in order to achieve the CP objectives, are described. The affects of these initiatives on local municipal wastewater treatment works are detailed with specific reference to significant reductions in incoming wastewater-borne heavy metals. The main challenge for companies has been data retrieval for the tool and overcoming social barriers for implementing the improvement options. Recommendations include redesigning the assessment tool.  相似文献   
440.
梅拉伦湖是瑞典中部100多万居民的供水源和娱乐区,有重大的环境影响.为了建立评估目前的营养水平和重金属污染水平的背景资料,分析了取自湖泊的沉积岩心.从硅藻推断的湖水磷浓度表明,20世纪前南比约克盆地(梅拉伦湖东部的一个盆地)中的营养物水平比以前假定的(约6ugTP/L)要高(10~20μgTP/L).从3个盆地(南比约克盆地、伊斯塞尔盆地以及艾斯雪盆地)获得的稳定性同位素和铅浓度分析结果表明,19世纪以及早些时候由于汇水盆地广泛开展的金属生产和加工,特别是在贝里斯拉根地区,使得该湖泊受到污染.在20世纪关闭了采矿和金属工厂之后该湖泊的铅污染形势有了相当大的好转过去的采矿业所造成的铅污染比20世纪末汽车尾气排放、矿石然料燃烧以及现代生产所造成的污染要严重.  相似文献   
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