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921.
Occurrence, sources, and inventory of hexabromocyclododecanes (HBCDs) in soils from Chongming Island, the Yangtze River Delta (YRD) 总被引:6,自引:0,他引:6
Hexabromocyclododecanes (HBCDs) is a concern due to their large usage combining with physico-chemical properties and toxicity to wildlife and human. However, very limited data were reported on HBCDs in soils, especially from rural area. In this study, 22 soil samples were collected from Chongming Island at estuary of the Yangtze River Delta, to investigate the level, diasteroisomer profile, potential sources, and mass inventory of HBCDs. The total concentrations ranged from not detected to 93.8 pg g−1 dry weight (dw) with a mean of 23.3 pg g−1 dw, which was at the low end of the global levels. The wide distribution of HBCDs in soils suggested that the local emissions of HBCD-containing materials and/or the inputs via atmospheric transport from other regions were two possible sources. Variation of HBCDs levels was observed in different types of soils. Woodland, tideland and road soils contained slightly higher HBCDs than those of farmland and grassland. Overall, γ-HBCD was the dominant diasteroisomer in soils, followed by α-HBCD and β-HBCD. Significant but weak correlations were only found between α-HBCD and β-HBCD versus TOC content in soils. Currently, the mass inventory of HBCDs in soils of Chongming Island was 5.3 kg. Based on these data, we gave perspective on human intake of HBCDs via soil ingestion by age. Local resident’s intakes ranged from 15.5 to 97.8 fg kg body weight−1 d−1, in which children are exposed more than adults. 相似文献
922.
923.
An overview of the methods used in the characterisation of natural organic matter (NOM) in relation to drinking water treatment 总被引:9,自引:0,他引:9
Matilainen A Gjessing ET Lahtinen T Hed L Bhatnagar A Sillanpää M 《Chemosphere》2011,83(11):1431-1442
Natural organic matter (NOM) is found in all surface, ground and soil waters. During recent decades, reports worldwide show a continuing increase in the color and NOM of the surface water, which has an adverse affect on drinking water purification. For several practical and hygienic reasons, the presence of NOM is undesirable in drinking water. Various technologies have been proposed for NOM removal with varying degrees of success. The properties and amount of NOM, however, can significantly affect the process efficiency. In order to improve and optimise these processes, the characterisation and quantification of NOM at different purification and treatment processes stages is important. It is also important to be able to understand and predict the reactivity of NOM or its fractions in different steps of the treatment. Methods used in the characterisation of NOM include resin adsorption, size exclusion chromatography (SEC), nuclear magnetic resonance (NMR) spectroscopy, and fluorescence spectroscopy. The amount of NOM in water has been predicted with parameters including UV-Vis, total organic carbon (TOC), and specific UV-absorbance (SUVA). Recently, methods by which NOM structures can be more precisely determined have been developed; pyrolysis gas chromatography-mass spectrometry (Py-GC-MS), multidimensional NMR techniques, and Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS). The present review focuses on the methods used for characterisation and quantification of NOM in relation to drinking water treatment. 相似文献
924.
925.
本文对1998-2008年湖北省武汉城市圈和鄂西生态文化旅游圈的生物资源生态足迹及其组成、人均生物资源生态足迹、生物资源生态承载量和生物资源生态赤字(盈余)进行了动态分析.研究表明,武汉城市圈生物资源生态足迹组成以耕地为主,其他生态生产性用地的足迹比例较小,各市州生物资源生态足迹整体呈现逐年增加的趋势,人均生物资源生态足迹小于省均值,生物资源生态承载量先升高后降低,各市州生物资源生态承载量由大到小排序为:黄冈、孝感、武汉、咸宁、天门、黄石、仙桃、鄂州、潜江,生态赤字呈增大趋势;鄂西生态圈除神农架外其他各市州的生物资源生态足迹均较大,林地足迹占主要地位,其总量对全省的贡献较大;人均生物资源生态足迹大于省均值,生物资源生态承载量呈增高趋势,各市州由大到小排序为:宜昌、十堰、襄樊、荆州、恩施、随州、荆门、神农架,该圈一直保持很高的生物资源生态盈余,但盈余值有减小的趋势. 相似文献
926.
碳捕集、利用与封存(CCUS)是一项新兴的、具有大规模减排潜力的技术,有望实现化石能源使用的CO2近零排放,被认为是进行温室气体深度减排最重要的技术路径之一.开展CCUS技术的研发和储备,将为中国未来温室气体减排提供一种重要的战略性技术选择,受到政府、企业和学术界的广泛关注.本文从CCUS技术产生和发展的背景出发,概括了该技术的特点及存在的主要同题,总结了当前中国CCUS技术政策,介绍了中国CCUS技术研发、试点示范、国际合作等的开展情况,并通过与欧美等发达国家CCUS技术发展与示范活动现状的对比,初步分析了中国CCUS技术发展方面存在的主要不足.为进一步推动我国CCUS技术的研发与示范,文章提出应加强国家层面的技术政策指导和宏观协调、引导资源有效配置;推动建设行业间的CCUS技术合作平台;重视CCUS来来技术应用软环境建设等有针对性的建议. 相似文献
927.
香港典型地质遗迹资源与地质公园建设 总被引:1,自引:0,他引:1
香港素以金融、商业贸易中心闻名于世界,但香港境内所发育的曲折有致的岩石海岸、幽远宁静的海滩、巍峨多姿的群山、造型奇异的岛礁,弥足珍贵的自然生态和地质遗迹资源却鲜为人知。本文在对香港地质概况进行简单介绍的基础上,对香港地质遗迹资源进行系统分类和对比分析,指出西贡万宜水库至果洲群岛方圆近150 km2范围内发育的十分典型、极具规模的六方柱状节理构造景观是世界上同类岩石中罕见的地质现象,其分布面积大,露头完整,具有稀缺性、独特性和典型性,最后对香港国家地质公园一个公园,两个园区,八个景区的空间结构及每个园区的主要地质遗迹资源进行了系统归纳总结。香港国家地质公园的建立很好的起到了保育地质多样性的首要目标,同时很好地推动了香港的地质教育和科普发展。 相似文献
928.
Zhang Mingxi 《中国人口.资源与环境(英文版)》2011,9(2):84-89
Levying carbon tax is conducive to reducing carbon dioxide emissions and protecting the environment.The author firstly reviewed some relevant empirical studies on carbon tax both home and abroad,and then established the CGE model and simulated levying carbon tax in China.The study found that levying carbon tax would have little impact on China’s economy:in a short-term,China’s GDP might decrease by 0.51%,while in a long-term it might decrease by 0.08%;however,the carbon dioxide emissions would be substantially reduced.Meanwhile,levying carbon tax has some negative impact on the output of each industry in the very economic structure;of this,the mineral extractive industries would be influenced the most.Then the author summarized experience of levying carbon tax in foreign countries. 相似文献
929.
Sequestration of organochlorine pesticides in soils of distinct organic carbon content 总被引:1,自引:0,他引:1
Zhang N Yang Y Tao S Liu Y Shi KL 《Environmental pollution (Barking, Essex : 1987)》2011,159(3):700-705
In the present study, five soil samples with organic carbon contents ranging from 0.23% to 7.1% and aged with technical dichlorodiphenyltrichloroethane (DDT) and hexachlorocyclohexane (HCH) for 15 months were incubated in a sealed chamber to investigate the dynamic changes of the OCP residues. The residues in the soils decreased over the incubation period and finally reached a plateau. Regression analysis showed that degradable fractions of OCPs were negatively correlated with soil organic carbon (SOC) except for α-HCH, while no correlation was found between degradation rate and SOC, which demonstrated that SOC content determines the OCP sequestration fraction in soil. Analysis of the ratio of DDT and its primary metabolites showed that, since it depends on differential sequestration among them, magnitude of (p,p′-DDE + p,p′-DDD)/p,p′-DDT is not a reliable criterion for the identification of new DDT sources. 相似文献
930.
Pan X Tang J Chen Y Li J Zhang G 《Environmental pollution (Barking, Essex : 1987)》2011,159(12):3515-3521
PCN congeners were analyzed in marine and riverine sediments of the Laizhou Bay area, North China. Concentrations of PCNs ranged from 0.12 to 5.1 ng g−1 dry weight (dw) with a mean value of 1.1 ng g−1 dw. The levels of PCNs varied largely, with industrial group approximately ten folds higher than those of the rural in riverine sediment. A strong impact by direct discharge from local factories was suggested. Similar compositional profiles were found within groups. High resemblance of compositional profiles between industrial samples and Halowax 1014 was observed. It was indicated that PCNs in riverine sediments were mainly from release of industrial usage, with additional contributions from industrial thermal process at certain sites. In marine sediments, it was suggested that PCNs along the coast of Laizhou Bay were mainly controlled by riverine input. While in the central bay, PCN distributions were possibly impacted by combined multiple factors. 相似文献