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961.
Anttila A Leppänen AP Rissanen K Ylipieti J 《Journal of environmental radioactivity》2011,102(7):659-666
Samples of summer pasture plants that reindeer feed on were collected in order to study 137Cs concentrations in different plant species and in species nested in certain site types, and to study the regional distribution of 137Cs in the Finnish reindeer management area. Plant species were categorized by the site types of mineral soil forest (xeric heath forest and mesic heath forest) and peatland. A third category called ’other plant species’ included plants with various site types, poorly determined species and species with poor statistics. The 137Cs concentrations in different site types differed significantly. The mean 137Cs concentrations of the whole reindeer management area in the xeric heath forest plant species was 44 ± 27 Bq/kg dw, in the mesic heath forest plant species 75 ± 59 Bq/kg dw and in the peatland plant species 219 ± 150 Bq/kg dw. The peatland species uptake 137Cs more efficiently than plant species of mineral soil forests. A particularly efficient collector of 137Cs was Trichophorum sp. It is suggested that Trichophorum sp. could be used as an indicator species for reindeer summer fodder plants. The highest concentrations of 137Cs were found in Southern Lapland and the lowest in Northern Lapland. Today, the concentrations of 137Cs in summer pasture plants that reindeer feed on in Finland are at such a level that there is no need to avoid any plant species. In the case of future nuclear fallout, reindeer grazing in peatlands would increase concentrations of 137Cs in reindeer meat. 相似文献
962.
LCA of local strategies for energy recovery from waste in England, applied to a large municipal flow
Tunesi S 《Waste management (New York, N.Y.)》2011,31(3):561-571
An intense waste management (WM) planning activity is currently undergoing in England to build the infrastructure necessary to treat residual wastes, increase recycling levels and the recovery of energy from waste. From the analyses of local WM strategic and planning documents we have identified the emerging of three different energy recovery strategies: established combustion of residual waste; pre-treatment of residual waste and energy recovery from Solid Recovered Fuel in a dedicated plant, usually assumed to be a gasifier; pre-treatment of residual waste and reliance on the market to accept the ‘fuel from waste’ so produced. Each energy recovery strategy will result in a different solution in terms of the technology selected; moreover, on the basis of the favoured solution, the total number, scale and location of thermal treatment plants built in England will dramatically change. To support the evaluation and comparison of these three WM strategy in terms of global environmental impacts, energy recovery possibilities and performance with respect to changing ‘fuel from waste’ market conditions, the LCA comparison of eight alternative WM scenarios for a real case study dealing with a large flow of municipal wastes was performed with the modelling tool WRATE. The large flow of waste modelled allowed to formulate and assess realistic alternative WM scenarios and to design infrastructural systems which are likely to correspond to those submitted for approval to the local authorities. The results show that all alternative scenarios contribute to saving abiotic resources and reducing global warming potential. Particularly relevant to the current English debate, the performance of a scenario was shown to depend not from the thermal treatment technology but from a combination of parameters, among which most relevant are the efficiency of energy recovery processes (both electricity and heat) and the calorific value of residual waste and pre-treated material. The contribution and relative importance of recycling and treatment/recovery processes change with the impact category. The lack of reprocessing plants in the area of the case study has shown the relevance of transport distances for recyclate material in reducing the efficiency of a WM system. Highly relevant to the current English WM infrastructural debate, these results for the first time highlight the risk of a significant reduction in the energy that could be recovered by local WM strategies relying only on the market to dispose of the ‘fuel from waste’ in a non dedicated plant in the case that the SRF had to be sent to landfill for lack of treatment capacity. 相似文献
963.
964.
输变电项目竣工环保验收存在的问题及对策分析 总被引:1,自引:0,他引:1
结合输变电项目环保验收的调查实践,分析了输变电项目竣工环保验收中存在问题,提出对策及建议。 相似文献
965.
对火电厂液氨贮存风险评价中的三类典型事故(化学爆炸、管道泄漏和贮罐整体破裂)影响范围的计算方法进行了探讨。以某火电厂2×1000MW机组为例,当发生化学爆炸事故时,爆炸冲击波损害等级1、2、3、4的影响区域半径分别为78.3、156.6、391.5和1044m;管道泄漏和贮罐整体破裂所引发的中毒事故中,后者对环境的影响较大。若事故发生后10min内得到有效控制,则在F大气稳定度、1.5m/s风速条件下,贮罐整体破裂半致死浓度的影响区域半径(r值)为344.6m,大于管道泄漏r值(205.8m);若事故发生后不考虑控制措施,则在F大气稳定度、1.5 m/s风速条件下,贮罐整体破裂半致死浓度的影响区域半径r值为561 m。 相似文献
966.
在全球风电市场稳步发展的背景下,发展中国家(地区)的风电市场也都呈现快速发展的趋势,在各国风电发展持续升温的前提下,未来我国风电发展潜力巨大。列举了非洲、印度、拉丁美洲、东欧、中东等5个发展中国家(地区)未来风电发展规划情况,在总结这些国家或地区风电发展特点的基础上,对我国未来风电发展提出建议。 相似文献
967.
The impairment of root growth and photosynthetical functioning are the main impacts of trace elements on woody plant seedlings. In this work, we assessed the response of Holm oak (Quercusilex subsp. ballota) and mastic shrub (Pistacia lentiscus) seedlings to high concentrations of Cd and Tl in the rhizosphere. These are non-essential trace elements, with a potential high mobility in the soil-plant system. Seedlings of these species are frequently used in the afforestation of degraded soils in mining areas. Plants were exposed to different levels of Cd (20, 80 and 200 mg L−1) and Tl (2, 10 and 20 mg L−1) in a sand culture. Biomass allocation, growth rates, chlorophyll fluorescence and gas exchange were studied. Both metals affected root biomass. Cadmium produced an increase in the root mass ratio and a decrease in the specific leaf area of the plants in oak seedlings, while Tl did not provoke such response. Mastic plants were more sensitive to Tl and Cd than oak plants. Between elements, Tl provoked more severe toxic effects in the plants, affecting the antennae complexes and reaction centers of the photosystem II. Both elements decreased net assimilation rates (down to a 20% of the control plants) and stomatal conductance (5-10% of the values for the control plants). Cadmium was highly retained in the roots of both species, while Tl was highly translocated into the leaves. In general, Holm oak showed a higher tolerance for Cd than for Tl, and a higher resistance to both metals than mastic shrub, due to a high capacity for Cd retention at the root level. However, such accumulation in roots may induce water stress in the seedling exposed to Cd. 相似文献
968.
Dental clinics: a point pollution source, not only of mercury but also of other amalgam constituents
Current literature suggests that amalgam waste from dental clinics is a point-source of mercury pollution in the environment. However, apart from mercury, other amalgam constituents (e.g. Ag, Sn, Cu, and Zn) in dental clinics’ wastewater have not been reported in the literature before. The objective of this study was to evaluate the concentrations of mercury and other metals in the wastewater of some dental clinics and the influent of a wastewater treatment plant in Al-Madinah Al-Munawarah (KSA). Samples were collected over a 2-month period from three dental clinics and analyzed for metals using ICP-MS. The mean concentrations of Hg, Ag, Sn, Cu, and Zn in the samples were 5.3 ± 11.1, 0.49 ± 0.96, 3.0 ± 10.7, 10.0 ± 14.5, and 76.7 ± 106 mg L−1, respectively. Additionally, high concentrations of other metals such as Mg (14.4 ± 15.2 mg L−1), Mn (3.0 ± 4.6 mg L−1), Fe (3.0 ± 4.5 mg L−1), Sr (1.6 ± 2.4 mg L−1), and Ba (6.9 ± 10.3 mg L−1) were also found. These values are much higher than the local permissible limits. Most of the metals of interest were also detected in the influent of the wastewater treatment plant. This renders dental clinics wastewater a hazardous waste which should be properly treated before it is discharged into the environment. 相似文献
969.
边坡生态防护用灌木植物耐旱性试验研究与应用 总被引:1,自引:0,他引:1
本论文针对我国公路各地野生植物资源的开发利用水平还较低的实际情况,低品味的掠夺式索取,严重地影响了野生植物资源的自然更新和可持续利用。通过优选六种野生植物进行试验,对胡颓子(Elaeagnus bockiiD iels)、三颗针(Berberis julianae Schneid)、金丝梅(Hypericum patulum Thum b)、十大功劳(Mahonia fortunei(B ind l)Fedde)、刺梨(Rosa roxburghiiTrau)和火棘(Pyracantha fortuneana(M axim)L i.)等六种野生灌木为研究材料的水分对渗透调节物质,电导率,丙二醛,叶绿素含量,光合性状等影响进行了研究。分析了干旱胁迫下六种野生植物的生理生化指标的变化情况,对六种野生植物抗旱性强弱进行了综合评价,研究成果应用于四川省二郎山至康定段公路,降低了公路绿化后期养护成本。 相似文献
970.
郑州新力电力有限公司5号炉电除尘器2003年改造为袋式除尘器,该除尘器的滤袋突破传统4年的使用寿命,已达到6年运行使用时间,经检测滤袋预期使用寿命至少还有6个月以上。着重介绍了袋式除尘器的设计、制造、安装、运行及维护管理等方面的经验,并分析研究了滤袋长寿命的成因。 相似文献