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101.
Study of the influence of different organic pollutants on Cu accumulation by Halimione portulacoides
C. Marisa R. Almeida A. Claúdia Dias Ana P. Mucha A.A. Bordalo M. Teresa S.D. Vasconcelos 《Estuarine, Coastal and Shelf Science》2009
The influence of each of four organic pollutants selected from among those commonly found in coastal areas, 1,1-dichloro-2,2-bis(p-chlorophenyl) ethylene (DDE), monobutyltin (MBT), Triton X-100 and polycyclic aromatic hydrocarbons (PAHs), on Cu accumulation by Halimione portulacoides was investigated. Experiments were carried out in a laboratory setting, either in hydroponics (sediment elutriate) or in a salt marsh sediment (Cávado River, NW Portugal) soaked in elutriate. Groups of H. portulacoides were exposed to media for 6 days spiked with 10 mg/L Cu(II) and with one of the selected pollutants, at an environmentally realistic concentration. DDE and MBT did not cause any major change on Cu accumulation by H. portulacoides, whereas PAHs slightly increased accumulation only in hydroponics i.e. in the absence of sediment. On the other hand, the non-ionic surfactant Triton X-100 markedly favoured Cu accumulation on plant roots both in the presence and absence of sediment. The addition of DDE, MBT and Triton X-100 also favoured Cu solubility from sediments. Therefore, the simultaneous presence of pollutants from different nature (inorganic and organic) in the estuarine environment may result in a composition of water column, pore water, sediment or biota different of that expected considering the effect of each individual pollutant. 相似文献
102.
TheVerticalTransportofAirPollutantsbyConvectiveClouds.PartⅢ:TransportFeaturesofDifferentCloudSystemsKongFanyou(孔凡铀)andQinYu(秦... 相似文献
103.
Xiufeng Yin Shichang Kang Maheswar Rupakheti Benjamin de Foy Ping Li Junhua Yang Kunpeng Wu Qianggong Zhang Dipesh Rupakheti 《地学前缘(英文版)》2021,12(6):114-128
Air pollution is a grand challenge of our time due to its multitude of adverse impacts on environment and society,with the scale of impacts more severe in developing countries,including China.Thus,China has initiated and implemented strict air pollution control measures over last several years to reduce impacts of air pollution.Monitoring data from Jan 2015 to Dec 2019 on six criteria air pollutants(SO2,NO2,CO,O3,PM2.5,and PM1o)at eight sites in southwestern China were investigated to understand the situation and analyze the impacts of transboundary air pollutants in this region.In terms of seasonal variation,the maximum concentrations of air pollutants at these sites were observed in winter or spring season depending on individual site.For diurnal variation,surface ozone peaked in the afternoon while the other pollutants had a bimodal pattern with peaks in the morning and late afternoon.There was limited trans-port of domestic emissions of air pollutants in China to these sites.Local emissions enhanced the concen-trations of air pollutants during some pollution events.Mostly,the transboundary transport of air pollution from South Asia and Southeast Asia was associated with high concentrations of most air pollu-tants observed in southwestern China.Since air pollutants can be transported to southwestern China over long distances from the source regions,it is necessary to conduct more research to properly attribute and quantify transboundary transport of air pollutants,which will provide more solid scientific guidance for air pollution management in southwestern China. 相似文献
104.
不同季风时节北京近地面大气颗粒物中7Be和POPs的变化 总被引:1,自引:0,他引:1
2009年8月至2010年7月在东亚季风区中纬度城市北京连续一年以每周3天的时间尺度同步采集近地面大气中气溶胶样品并测定了宇宙射线成因核素7Be 和8种有机氯农药(OCPs)、7种多氯联苯(PCBs)的浓度。7Be浓度全年平均值为(8.39±0.49) mBq/m^3,显著高于欧洲地区具有相同纬度的城市。最高值出现在9月(15.64 mBq/m^3),最低值出现在5月(1.35 mBq/m^3)。夏季7Be浓度值较低,春、秋季浓度值较高。对大气气溶胶中7Be进行不同季风时节的比较要比季节性的比较可更好地揭示7Be的变化规律及其来源。夏季的低值与东南季风导致的多降雨气象条件有关。秋季的高值为大气环流异常所致。OCPs和PCBs总浓度(∑OCPs和∑PCBs)呈现夏季低,秋、冬季高的现象。西风和西北风为北京市大气气溶胶中POPs浓度最高的季风时节。较高氯代PCBs (PCB153和PCB180)在冬季占主导优势。较高的PCB101和PCB118可能来自北京周边的污染源。在部分时期7Be与DDTs和δ-HCH有显著的相关性,而在春季和夏季PCB-101与7Be有很好的相关性。 相似文献
105.
Lourdes Vazquez‐Gomez Achille de Battisti Sergio Ferro Monica Cerro Silvia Reyna Carlos A. Martínez‐Huitle Marco A. Quiroz 《洁净——土壤、空气、水》2012,40(4):408-415
The electrochemical oxidation (EO) of diethyl phthalate (DEP) in aqueous solution was studied at Pb/PbO2 and Ti/SnO2 anode materials under galvanostatic‐experimental conditions. Results obtained clearly demonstrated that the anode plays a significant role for the optimization of the oxidation process, deciding the mechanisms and by‐products formed. DEP and by‐products of oxidation were also analyzed during various stages of the electrolysis reaction by HPLC and GC/MS techniques. Before the analysis by GC/MS technique, the samples were treated by solid phase microextraction (SPME) in order to concentrate the compounds from the reaction solution and identify all electrolysis intermediates. Current efficiencies (instantaneous current efficiency; ICE and total current efficiency; TCE) achieved during EO experiments were dependent on anode used and current density (20–40 mA cm?2) at 40°C. The results obtained demonstrated that the environmental electrochemical methods can be a feasible alternative for the wastewater treatment containing hazardous phthalates. 相似文献
106.
针对暴雨对空气质量的影响的问题,结合葫芦岛市环境监测中心站2010年市区空气质量逐日监测资料与葫芦岛市气象局气象观测资料,采用空气污染指数和空气质量指数法,分析了葫芦岛市空气质量时间分布特征及其与暴雨的关系。结果表明,在影响葫芦岛市空气质量的主要3种污染物——二氧化硫(SO2)、二氧化氮(NO2)和可吸入颗粒物(PM10)中PM10为首要污染物;3种污染物变化趋势基本一致,都是夏季污染最轻,冬季污染最重,春秋两季居中;暴雨与污染物浓度变化有着密切的关系,4次暴雨过程所在日3种污染物浓度都较低,且在强降水过后第一天污染物浓度继续降低。 相似文献
107.
108.
自然水体中污染物的迁移、转化规律与经泥沙吸附后的沉降、再悬浮等泥沙过程密切相关,其机制尚不明确。采用污染物输运年龄对泥沙影响进行了量化分析,并应用于南黄海辐射沙脊群西洋海域。基于水体中泥沙-污染物模型,推导了考虑泥沙影响的污染物输运年龄的计算方程,通过数值模拟分析了污染物分配系数KD对污染物输运年龄空间分布的影响。研究成果表明:计入泥沙影响后,污染物浓度显著减小,污染物输运年龄随之增大,表明泥沙对污染物扩散起阻碍作用;污染物分配系数KD表征泥沙吸附能力,污染物输运年龄与其呈一定的正相关性,当该系数达到一定值(KD=10^3L/g)时,泥沙吸附能力趋于饱和,污染物输运年龄不再发生显著改变。 相似文献
109.
A multi-residual method based on stir bar sorptive extraction coupled with thermal desorption-gas chromatography-mass spectrometry (SBSE-TD-GC-MS) has been developed to measure 49 organic pollutants (organochlorine pesticides, polycyclic aromatic hydrocarbons, polychlorinated biphenyls, polybrominated diphenyl ethers and nonylphenol) in seawater. Using 100 ml of water, the method exhibited good linearity, with recoveries between 86% and 118% and relative standard deviation between 2% and 24% for almost all compounds. The method was applied to determine target contaminants in Catalonian seawater, including coastal areas, ports and desalination plant feed water. Overall individual compound levels oscillated between 0.16 and 597 ng l−1; PAHs and nonylpenol were the compounds found at the highest concentrations. The method provided LODs between 0.011 and 2.5 ng l−1, lower than the Environmental Quality Standards (EQS) fixed by Directive 2008/105/EC. In compliance with the directive, this method can be used as a tool to survey target compounds and is aimed at protecting coastal ecosystems from chemical pollution. 相似文献
110.
Persistent organic pollutants (POPs) and heavy metals have been reported in a number of green turtle (Chelonia mydas) populations worldwide. However, due to ethical considerations, these studies have generally been on tissues from deceased and stranded animals. The purpose of this study was to investigate the use of blood samples to estimate the tissue contamination of live C. mydas populations. This study analysed 125 POP compounds and eight heavy metals in the blood, liver, kidney and muscle of 16 C. mydas from the Sea World Sea Turtle Rehabilitation Program, Gold Coast, Australia. Strong correlations were observed between blood and tissue concentrations for a number of POPs and metals. Furthermore, these correlations were observed over large ranges of turtle size, sex and condition. These results indicate that blood samples are a reliable non-lethal method for predicting chemical contamination in C. mydas. 相似文献