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911.
Environmental assessment of garden waste management in the Municipality of Aarhus, Denmark 总被引:1,自引:0,他引:1
An environmental assessment of six scenarios for handling of garden waste in the Municipality of Aarhus (Denmark) was performed from a life cycle perspective by means of the LCA-model EASEWASTE. In the first (baseline) scenario, the current garden waste management system based on windrow composting was assessed, while in the other five scenarios alternative solutions including incineration and home composting of fractions of the garden waste were evaluated. The environmental profile (normalised to Person Equivalent, PE) of the current garden waste management in Aarhus is in the order of −6 to 8 mPE Mg−1 ww for the non-toxic categories and up to 100 mPE Mg−1 ww for the toxic categories. The potential impacts on non-toxic categories are much smaller than what is found for other fractions of municipal solid waste. Incineration (up to 35% of the garden waste) and home composting (up to 18% of the garden waste) seem from an environmental point of view suitable for diverting waste away from the composting facility in order to increase its capacity. In particular the incineration of woody parts of the garden waste improved the environmental profile of the garden waste management significantly. 相似文献
912.
Gottschalk F Ort C Scholz RW Nowack B 《Environmental pollution (Barking, Essex : 1987)》2011,159(12):3439-3445
Probabilistic material flow analysis and graph theory were combined to calculate predicted environmental concentrations (PECs) of engineered nanomaterials (ENMs) in Swiss rivers: 543 river sections were used to assess the geographical variability of nano-TiO2, nano-ZnO and nano-Ag, and flow measurements over a 20-year period at 21 locations served to evaluate temporal variation. A conservative scenario assuming no ENM removal and an optimistic scenario covering complete ENM transformation/deposition were considered. ENM concentrations varied by a factor 5 due to uncertain ENM emissions (15%-85% quantiles of ENM emissions) and up to a factor of 10 due to temporal river flow variations (15%-85% quantiles of flow). The results indicate highly variable local PECs and a location- and time-dependent risk evaluation. Nano-TiO2 median PECs ranged from 11 to 1′623 ng L−1 (conservative scenario) and from 2 to 1′618 ng L−1 (optimistic scenario). The equivalent values for nano-ZnO and nano-Ag were by factors of 14 and 240 smaller. 相似文献
913.
In the new European Pesticide Regulation (EC) No. 1107/2009, the harmonisation of approaches for estimation of the environmental exposure of pesticides is considered a major goal. Several member states currently require their own models for the calculation of predicted environmental concentrations (PEC) in surface water. The variety of methods makes risk evaluations rather time-consuming for both notifiers and evaluating authorities. In the present study we compare surface water concentrations of 19 compounds using EU and country-specific models and risk assessment approaches to evaluate to which extent the resulting estimated exposure concentrations differ. Our results show that EU and country specific approaches and the resulting surface water concentrations differ considerably regarding basic model assumptions and assessment methods. The results indicate that the aimed harmonisation of risk assessment approaches within the EU will be difficult based on current models. New scenarios may help to achieve a harmonisation taking country-specific features into account. 相似文献
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917.
在阐述了宁夏地区光伏发电发展的优势及发展现状的基础上,分析了光伏发电开发利用对宁夏生态环境产生的积极和消极的影响,并为降低消极影响提出了相应的对策;为了定量直观的评估光伏发电积极影响和消极影响所产生的环境效益,分别建立了节能减排、防风固沙和土地增值、景观效应、植被恢复费用、噪声污染超标罚款、光污染费用等价值模型及光伏发电总的生态环境效益价值模型;最后以中电投宁夏能源铝中卫香山光伏电站为例进行计算验证,结果表明模型的合理性和准确性,同时光伏电站的节能减排效益显著。相对于传统的火力发电,表现了优越的环境效益。 相似文献
918.
Fielding JL 《Disasters》2012,36(3):477-494
This paper explores the environmental inequalities of living in the floodplains of England and Wales and the differences in flood awareness of those 'at risk'. An area comparison is made between an etic, objective flood risk exposure, and an emic, subjective perception of that risk by social class. In all areas except the Midlands, the working classes were more likely to reside in the floodplains; the greatest exposure inequality is seen in the North East and Anglian regions. Flood awareness in the Anglian regions was much lower than average, but there were no significant class differences. In the Thames region, despite equal flood risk exposure between classes, the most deprived displayed the least awareness of flood risk. In the North East, inequalities in the distribution of flood risk exposure accompanied inequalities in perception, resulting in the least aware and most deprived experiencing the greatest flood risk. 相似文献
919.
王涛 《长江流域资源与环境》2012,21(Z1):111-118
南通地区位于长江三角洲北翼,其冰后期的环境变化以最大海侵时期为界,之前为海侵期,表现为海水入侵,陆地面积减少。之后海面趋于稳定,长江泥沙在河口地区持续沉积的作用下,表现为南通地区的逐渐成陆过程。利用收集的84个分布于南通地区及附近的钻孔剖面资料,将其按不同厚度的沉积相进行整理,结合前人研究成果,根据不同的数据基础运用IDW(Inverse Distance Weighted)插值对南通地区冰后期沉积厚度分布和环境变化过程分别进行了初步研究。结果表明:南通地区古河谷区是冰后期主要的泥沙沉积区,沉积物厚度、体积和重量大于北翼地区,北翼前缘沉积要大于后缘。冰后期古河谷区沉积泥沙4 8922×108 t,北翼地区沉积泥沙1 0453×108 t,二者之比约为47〖DK〗∶10,泥沙沉积强度之比约2〖DK〗∶1。从冰后期海侵初期到最大海侵时期,再到南通成陆的晚期,南通地区水域面积比例先由622%上升到95%,再缩减到331%,陆地面积比例先由378%缩减到5%,而后又上升至669%。尽管钻孔资料可以为南通地区有历史记载之前的时期提供宏观的环境变化框架,但由于钻孔资料在测年数据及沉积相的划分方面分辨率较低,在表现南通地区历史时期的环境变化方面存在不足,需要结合考古、文物等历史资料和土壤分布等自然地理信息进行更为详细的研究 相似文献
920.
地区水利规划环评处于起步阶段,存在评价形式化、方法单一化以及指标权重确定的主观性较强等问题。针对以往评价中的不足,提出了运用可变模糊集理论及其模型进行综合评价的方法。以江苏省水利发展规划作为研究实例,建立指标体系,采用模糊聚类循环迭代模型进行主客观综合指标权重的计算;从重点工程空间布局角度出发,运用调整后的可变模糊识别模型进行各市环境影响的相对优属度计算。结果表明,全省规划方案的环境影响相对优属度大于现状和零方案,南通市的相对优属度最大,其次是苏州和无锡。与层次分析法进行对比,该理论及其模型适用于地区水利规划环境影响综合评价 相似文献