连环湖牙门气泡沉积物重金属演化和污染研究

2010年8月在牙门气泡的湖心位置采集了柱状沉积岩心.采用HNO3-HClO4-HF联合消解并运用ICP-MS测试了柱状沉积岩心中金属元素Cr、Cu、Mn、Ni、Fe、Pb、Zn、Cd、Al、Ba、Ca、K、Li、Mg、Na和Sr的含量,结合沉积岩心年代测定,研究了该湖区沉积物重金属元素演化特征及污染历史.应用富集系数法探讨了湖泊重金属的污染特征.结果表明,1950年以前各元素含量变化趋势平稳,1950～1990年间波动较大,1990年以后金属元素Mn、Zn、Cd、Pb、Fe、Ni、Cr、Cu、Ca、Li和Sr浓度明显增加.牙门气泡重金属元素Mn、Zn、Cd、Pb存在轻微污染,而Ni、Cr和Cu无污染.     

青岛近海不同天气状况下大气气溶胶中金属元素浓度分布特征研究

为探究青岛近海不同天气下气溶胶中金属元素的浓度分布特征,于2012年4~5月,2012年8月~2013年3月在青岛近海采集了总悬浮颗粒物(TSP)样品,利用电感耦合等离子体质谱法(ICP-MS)和电感耦合等离子体原子发射光谱法(ICPAES)分析了主要微量金属元素.结果表明,Al、Ca、Fe、Na、K和Mg是TSP中主要的金属元素,质量浓度占所测元素总浓度的94.2%.TSP及金属元素浓度月变化明显,Fe、Al、K、Ca、Mg、Zn、Ba、Mn、Ti、Sr和Li均在11月和1月浓度最高,Be、Sc、Co、Ni和Cr在1月最高,Na在8、11和2月较高,12月最低,Pb在1月和2月最高,8月和12月最低.富集因子表明Be、Co、Al、Ca、Fe、K、Mg、Mn、Sr和Ti主要受自然源影响,Li、Cr、Ni、Zn、Ba和Na除受自然源外,还受部分人为源影响,Pb主要来自人为源.不同天气状况对TSP及其金属元素浓度影响较大,除Ti外,所测元素浓度均在烟雾天最高.与晴天相比,烟雾天除Ti外,其余元素均升高,增幅为1~4倍,雾天Li、Be、Cr、Ni、Al、Fe、Mg和Mn变化不大,Pb和Na升高较多,Co、Ca和Ti降低较多,霾天Cr、Co和Ti降低,其余元素浓度升高,增幅为1~3倍.大部分元素在晴天富集因子最小,雾天富集因子最大.Ni、Zn、Ba、K、Na、Pb和Sr富集因子为晴<霾<烟雾<雾,Fe和Mn为晴<烟雾<霾<雾,Al和Mg为晴<雾<霾<烟雾,其余金属不同天气下富集因子的变化规律各不相同.     

淀山湖沉积物重金属分布特征及其与底栖动物的关系

采用X-ray荧光光谱法测定了淀山湖沉积物中17种重金属元素的含量,分析了各元素的空间分布特征,并采用Hkanson潜在生态风险指数法评价了Cd、As、Pb、Cu、Cr、Zn6种重金属的潜在生态风险.结果表明：沉积物中重金属含量大小顺序为：Al〉Fe〉K〉Na〉Ca〉Mg〉Ti〉Mn〉Zr〉Zn〉Sr〉Rb〉Cu〉C...     

河南夏邑县长寿现象与饮用水水质的关系

基于野外调查采样和室内分析,探讨了夏邑县饮用水中化学元素和长寿人口分布特征以及夏邑县不同乡镇饮用水中化学元素的差异及其与长寿人口分布的相关性。结果表明,夏邑县长寿人口具有明显的空间聚集性,县境内80岁以上及95岁以上人口均呈东北-西南带状分布;与对照相比,夏邑县饮用水中Ca、Cu、Mg、Mn、Pb、Se、Sr、Zn等元素含量较高,而Cd、Cr、Fe、Hg、K、Na等元素含量较低;长寿水平相同的乡镇中百岁人口比例存在明显差异,百岁人口比例较高的乡镇饮用水中Ca、Fe、Mn、Se、Sr等元素富集,而Cu、K、Pb等元素亏损。研究表明,富Ca、Mg、Mn、Se、Sr等生命元素且无重金属污染的弱碱性饮用水是区域长寿的一个重要原因,而饮用水中Ca、Mg、Mn、Se、Sr、Pb分布不均是限制夏邑县百岁人口分布的关键因素。     

北京市春夏季降水及其对大气环境的影响研究

通过采集北京市2015年春夏季大气降水和大气颗粒物样品,分析研究了大气降水的理化特性,时空变化特征,来源以及对大气颗粒物的影响.结果表明,北京市春夏季降水量主要集中于夏季,降水p H值在南城和北城分别为6.26和6.08,呈偏中性,均表现为春季大于夏季.降水中地壳元素Al和Fe含量较高,Ti、V和Ce含量较低.污染元素Ca和S含量最高,Na和Mg含量较高,Zn、Mn、Cu、Sr、Pb和Ni含量较低,其中Na、Mg、Sr和Ni呈现轻度富集,Ca、Mn和Pb呈现中度富集,Cu、Zn和S呈现严重富集.此外,降水中元素浓度具有显著的季节变化,二次污染元素S表现为夏季高于春季,而其它元素均表现为春季高于夏季;同时也具有较大的空间变化,除Pb元素外,均为南城高于北城.降水中化学组分主要来源于地面扬尘、建筑活动、燃煤、机动车尾气和工业排放.大气降水对大气颗粒物的去除率受降水强度以及前一天空气质量的影响较大,且对细颗粒物PM_(2.5)中污染元素Cu、Zn、Mn和Na清除效果显著,对粗颗粒物PM_(10)中地壳元素Al和建筑尘相关元素Mg和Ca去除效果明显.     

京津冀地区城市环境空气颗粒物及其元素特征分析

于2013年四个季度,选择京津冀3个主要城市和1个对照点,以及4个全国大气背景站,同步采集环境空气颗粒物PM10和PM2.5样品,采用微波消解ICP-MS法分析样品中的68种元素.结果表明,京津冀3个城市四个季度PM10和PM2.5均超过国家二级标准限值,且采暖季高于非采暖季.全年PM2.5/PM10比值大于0.5,细颗粒物污染占主导.元素在PM2.5中所占比例高于PM10.而背景点颗粒物浓度低于标准限值,远低于城市点,且四个季节变化不大.在检出的57种元素中, Na、Mg、Al、S、K、Ca、Fe、Zn在0.1~10 μg/m3之间,P、Ti、Mn、Ni、Cu、Ba、Pb在10~100ng/m3之间,其他含量较低元素如Cd、Co、Ge、Ga、Zr、Sr、V等在0.01~10ng/m3之间.元素S、Na、K、Al、Fe、Mg、Ca等含量大于1%,P、Zn、Pb、Cu、Ba等其他元素含量介于0.1%~1%.富集因子分析结果提示,K、Ca、Cr、Fe、Cu、Zn、As、Cd和Pb等9种元素主要来源于人为污染,采暖季与非采暖季富集因子比值在1.1~3.5之间.因子分析提示,燃煤、工业污染源、燃油等是颗粒物污染的主要贡献因素.     

株洲市大气降尘中元素特征及来源分析

为研究湖南省株洲市大气降尘中多种元素的分布特征以及来源,于2012年1~12月对株洲市12个点的大气降尘样品进行采集并对其中28种元素的含量进行分析.结果表明,株洲市城区各采样点大气降尘年沉降量为23.14~114.67 g·m~(-2),其中工业区和商住混合区年均值分别为89.46 g·m~(-2)和33.20 g·m~(-2),低于其它工业城市;工业区和商住混合区降尘中分别有10种元素(Na、Mg、Al、K、Ca、Ti、Mn、Fe、Zn、Pb)和8种元素(Na、Mg、Al、K、Ca、Ti、Fe、Zn)含量大于1 000 mg·kg~(-1),其中工业区2种重金属元素(Zn、Pb)含量超过10 000 mg·kg~(-1),远高于地壳中的含量.株洲市大气降尘主要来源为金属冶炼、地表扬尘、汽车尾气、建筑粉尘和与Mo、Ba元素相关的工业生产.相关性分析、主因子分析和迁移特征分析表明降尘中Mn、Fe、Co、Cu、Zn、As、Se、Ag、Cd、Sn、Sb、Tl、Pb等13种元素主要来自株洲市工业区废气排放,其中Cu、Zn、As、Ag、Cd、Se和Pb等7种元素污染严重,工业区重金属元素含量是土壤背景值中含量的7.4~4 079.4倍,商住混合区是土壤背景值的3.6~1 413.4倍,背景比值最高的为Cd元素.工业区的污染程度明显高于商住混合区.     

鞍山市冬季大气PM_(2.5)中元素污染特征与来源解析

本文为探究鞍山市冬季大气细颗粒(PM_(2.5))中元素的污染特征和来源,于2016年1月在鞍山市6个监测点位采集PM_(2.5)样品,对PM_(2.5)载带的元素进行了浓度特征和富集因子分析,并通过因子分析确定了鞍山市PM_(2.5)中污染元素的主要来源。结果表明,K、Fe、Al、Ca、Na、Mg、Zn、Pb元素浓度含量之和占所有检测的14种元素浓度的97.13%;Cd、Zn、Pb、As、Cu五种元素属于极强富集,Ni属于强烈富集,Cr、Ca、V处于显著富集水平,Mg、K、Na、Fe呈现中度富集。因子分析结果表明,鞍山市冬季大气细颗粒物中污染元素主要来源于钢铁冶炼、机动车尾气、燃煤和建筑扬尘的复合型污染源。     

水泥工业区内土壤剖面金属元素量特征及其指示意义

为了研究水泥工业区内污染土壤中金属元素含量变化特征,对安徽省凤阳县水泥工业区内一条土壤剖面中金属元素(Al、Fe、Ca、Mg、K、Na、Cr、Ba、Mn、Zn)含量进行了测量。结果显示,土壤剖面分2层,第一层(0～20 cm)为污染层,该层Al、Fe、Mg、Na、Ba、Mn、Cr元素主要来源于自然土壤,没有富集,Ca、K、Zn元素主要来源于水泥粉尘的输入,存在富集,其中0～2 cm土壤的富集因子最大,Ca和Zn含量最高,指示0～2 cm土壤被污染的程度最深。第二层(20 cm以下)为土壤母质层,该层各金属元素含量相对比较稳定。由于0～2 cm土壤中Ca、Zn元素还没有大量向下淋溶,导致第一层土壤中Ca、Zn含量随采样深度的增加而减少。土壤剖面中Ca和Zn的含量能指示水泥粉尘对工业区土壤环境的污染,土壤母质层的Ca、Zn含量可以作为参考的警戒值。     

南京市秋季大气颗粒物中金属元素的粒径分布

在南京市仙林地区,采用ANDERSON八级撞击采样器,于2016年秋季采集了63个大气颗粒物有效样本,并利用ICP-MS分析了金属元素的含量.结合气象等资料,研究了大气颗粒物金属元素的粒径分布与富集特征,并对其来源进行了探讨.结果表明：南京秋季大气颗粒物质量浓度的粒径分布呈双峰型,峰值分别位于0.4~1.1和3.3~9μm;金属元素的粒径分布呈3种类型,一是粗粒子单峰型,峰值位于3.3~5.8μm,主要元素包括Na、Al、Ca、Mg、Co、Ce、Sr和Ba;二是细粒子单峰型,峰值位于0.4~1.1μm,主要元素包括Zn、As、Cd、Ag、Tl和Pb;三是粗细粒子双峰或多峰型,峰值位于1.1和5μm粒径段,主要元素包括K、Se、Li、Be、Mn、V、Cu、Cr、Ni和Fe.按富集因子的大小,可将元素分为3类,低富集元素包括Ba、Ca、Ce、Sr、Mg、Fe、Co、Mn、Be和V,中富集元素包括Li、Na、Ni、K和Cr,高富集元素包括Cu、Tl、Zn、As、Pb、Ag、Cd和Se.不同的粒径分布和富集水平反映了大气颗粒物的来源特征.研究结果可以为深入认识大气颗粒物金属元素的来源及其环境与健康效应提供科学依据.     

Toxic effects of acetochlor, methamidophos and their combination on nifH gene in soil

Toxic effects of two agrochemicals on nifH gene in agricultural black soil were investigated using denaturing gradient gel electrophoresis （DGGE） and sequencing approaches in a microcosm experiment. Changes of soil nifH gene diversity and composition were examined following the application of acetochlor, methamidophos and their combination. Acetochlor reduced the nifH gene diversity （both in gene richness and diversity index values） and caused changes in the nifH gene composition. The effects of acetochlor on nifH gene were strengthened as the concentration of acetochlor increased. Cluster analysis of DGGE banding patterns showed that nifH gene composition which had been affected by low concentration of acetochlor （50 mg/kg） recovered firstly. Methamidophos reduced nifH gene richness that except at 4 weeks. The medium concentration of methamidophos （150 mg/kg） caused the most apparent changes in nifH gene diversity at the first week while the high concentration of methamidophos （250 mg/kg） produced prominent effects on nifH gene diversity in the following weeks. Cluster analysis showed that minimal changes of nifH gene composition were found at 1 week and maximal changes at 4 weeks. Toxic effects of acetochlor and methamidophos combination on nifH gene were also apparent. Different nifH genes （bands） responded differently to the impact of agrochemicals： four individual bands were eliminated by the application of the agrochemicals, five bands became predominant by the stimulation of the agrochemicals, and four bands showed strong resistance to the influence of the agrochemicals. Fifteen prominent bands were partially sequenced, yielding 15 different nifH sequences, which were used for phylogenetic reconstructions. All sequences were affiliated with the alpha- and beta-proteobacteria, showing higher similarity to eight different diazotrophic genera.     

Arsenic uptake by arbuscular mycorrhizal maize （Zea mays L.） grown in an arsenic-contaminated soil with added phosphorus

The effects of arbuscular mycorrhizal (AM) fungus (Glomus mosseae) and phosphorus (P) addition (100 mg/kg soil) on arsenic (As) uptake by maize plants (Zea mays L.) from an As-contaminated soil were examined in a glasshouse experiment.Non-mycorrhizal and zero-P addition controls were included.Plant biomass and concentrations and uptake of As,P,and other nutrients,AM colonization,root lengths,and hyphal length densities were determined.The results indicated that addition of P significantly inhibited root colonization and development of extraradical mycelium.Root length and dry weight both increased markedly with mycorrhizal colonization under the zero-P treatments,but shoot and root biomass of AM plants was depressed by P application.AM fungal inoculation decreased shoot As concentrations when no P was added,and shoot and root As concentrations of AM plants increased 2.6 and 1.4 times with P addition,respectively.Shoot and root uptake of P,Mn,Cu,and Zn increased,but shoot Fe uptake decreased by 44.6%,with inoculation, when P was added.P addition reduced shoot P,Fe,Mn,Cu,and Zn uptake of AM plants,but increased root Fe and Mn uptake of the nonmycorrhizal ones.AM colonization therefore appeared to enhance plant tolerance to As in low P soil,and have some potential for the phytostabilization of As-contaminated soil,however,P application may introduce additional environmental risk by increasing soil As mobility.     

Impact of atrazine and nitrogen fertilizers on the sorption of chlorotoluron in soil and model sorbents

Sorption of chlorotoluron in ammonium sulfate, urea and atrazine multi-solutes system was investigated by batch experiments. The results showed application of nitrogen fertilizers to the soil could affect the behavior of chlorotoluron. At the same concentration of N, sorption of chlorotoluron decreased as the concentration of atrazine increased on the day 0 and 6 in soil, respectively. The sorption of chlorotoluron increased from 0 to 6 d when soils were preincubated with deionized water, ammonium sulfate and urea solution for 6 d. That indicated incubation time was one of the most important factors for the sorption of chlorotoluron in nitrogen fertilizers treatments. The individual sorption isotherms of chlorotoluron in rubbery polymer and silica were strictly linear in single solute system, but there were competition sorption between pesticides or between pesticides and nitrogen fertilizers. That indicated the sorption taken place by concurrent solid-phase dissolution mechanism and sorption on the interface of water-organic matter or water-mineral matter.     

Degradation of metabolites accumulated of benzo[a]pyrene by coupling Penicillium Chrysogenum with KMnO4

Several main metabolites of benzo[a]pyrene （BaP） formed by Penicillium chrysogenum, Benzo[a]pyrene-1,6-quinone （BP 1,6- quinone）, trans-7,8-dihydroxy-7,8-dihydrobenzo[a]pyrene （BP 7,8-diol）, 3-hydroxybenzo[a]pyrene （3-OHBP）, were identified by high-performance liquid chromatography （HPLC）. The three metabolites were liable to be accumulated and were hardly further metabolized because of their toxicity to microorganisms. However, their further degradation was essential for the complete degradation of BaP. To enhance their degradation, two methods, degradation by coupling Penicillium chrysogenum with KMnO4 and degradation only by Penicillium chrysogenum, were compared; Meanwhile, the parameters of degradation in the superior method were optimized. The results showed that （1） the method of coupling Penicillium chrysogenum with KMnO4 was better and was the first method to be used in the degradation of BaP and its metabolites; （2） the metabolite, BP 1,6-quinone was the most liable to be accumulated in pure cultures; （3） the effect of degradation was the best when the concentration of KMnO4 in the cultures was 0.01% （w/v）, concentration of the three compounds was 5 mg/L and pH was 6.2. Based on the experimental results, a novel concept with regard to the bioremediation of BaP-contaminated environment was discussed, considering the influence on environmental toxicity of the accumulated metabolites.     

Potential of plant polyphenol oxidases in the decolorization and removal of textile and non-textile dyes

In this study an effort has been made to use plant polyphenol oxidases; potato （Solanum tuberosum） and brinjal （Solanum melongena）, for the treatment of various important dyes used in textile and other industries. The ammonium sulphate fractionated enzyme preparations were used to treat a number of dyes under various experimental conditions. Majority of the treated dyes were maximally decolorized at pH 3.0. Some of the dyes were quickly decolorized whereas others were marginally decolorized. The initial first hour was sufficient for the maximum decolorization of dyes. The rate of decolorization was quite slow on long treatment of dyes. Enhancement in the dye decolorization was noticed on increasing the concentration of enzymes. The complex mixtures of dyes were treated with both preparations of polyphenol oxidases in the buffers of varying pH values. Potato polyphenol oxidase was significantly more effective in decolorizing the dyes to higher extent as compared to the enzyme obtained from brinjal polyphenol oxidase. Decolorization of dyes and their mixtures, followed by the formation of an insoluble precipitate, which could be easily removed simply by centrifugation.     

Removal of heavy metals from sewage sludge by low costing chemical method and recycling in agriculture

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Isolation and preliminary characterization of a 3-chlorobenzoate degrading bacteria

A study was conducted to compare the diversity of 2-, 3-, and 4-chlorobenzoate degraders in two pristine soils and one contaminated sewage sludge. These samples contained strikingly different populations of mono-chlorobenzoate degraders. Although fewer cultures were isolated in the uncontaminated soils than contaminated one, the ability of microbial populations to mineralize chlorobenzoate was widespread. The 3- and 4-chlorobenzoate degraders were more diverse than the 2-chlorobenzoate degraders. One of the strains isolated from the sewage sludge was obtained. Based on its phenotype, chemotaxonomic properties and 16S rRNA gene, the organism S-7 was classified as Rhodococcus erythropolis. The strain can grow at temperature from 4 to 37℃. It can utilize several （halo）aromatic compounds. Moreover, strain S-7 can grow and use 3-chlorobenzoate as sole carbon source in a temperatures range of 10-30℃ with stoichiometric release of chloride ions. The psychrotolerant ability was significant for bioremediation in low temperature regions. Catechol and chlorocatechol 1,2-dioxygenase activities were present in cell free extracts of the strain, but no （chloro）catechol 2,3- dioxygenase activities was detected. Spectral conversion assays with extracts from R. erythropolis S-7 showed accumulation of a compound with a similar UV spectrum as chloro-cis,cis-muconate from 3-chlorobenzoate. On the basis of these results, we proposed that S-7 degraded 3-chlorobenzoate through the modified ortho-cleave pathway.     

Single and joint effects of pesticides and mercury on soil urease

The influence of two pesticides including chlorimuron-ethyl and furadan and mercury （Hg） on urease activity in 4 soils （meadow burozem and phaeozem） was investigated. The soils were exposed to various concentrations of the two pesticides and Hg individually and simultaneously. Results showed that there was a close relationship between urease activity and organic matter content in soil. Chlorimuron-ethyl and furadan could both activate urease in the 4 soils. The maximum increment of urease activity by chlorimuronethyl was up to 14%-18%. There was almost an equal increase （up to 13%-21%） in the urease activity by furadan. On the contrary, Hg markedly inhibited soil urease activity. A logarithmic equation was used to describe the relationship （P〈0.05） between the concentration of Hg and the activity of soil urease in the 4 tested soils. Semi-effect dose （ED50） values by the stress of Hg based on the inhibition of soil urease in the 4 soils were 88, 5.5, 24 and 20 mg/kg, respectively, according to the calculation of the corresponding equations. The interactive effect of chlorimuron-ethyl or furadan with metal Hg on soil urease was mainly synergic at the highest tested concentrations.     

Organochlorine pesticides in soils under different land usage in the Taihu Lake region, China

A field study was conducted in the Taihu Lake region, China in 2004 to reveal the organochlorine pesticide concentrations in soils after the ban of these substances in the year 1983. Thirteen organochlorine pesticides (OCPs) were analyzed in soils from paddy field, tree land and fallow land. Total organochlorine pesticide residues were higher in agricultural soils than in uncultivated fallow land soils. Among all the pesticides, ΣDDX (DDD, DDE and DDT) had the highest concentration for all the soil samples, ranging from 3.10 ng/g to 166.55 ng/g with a mean value of 57.04 ng/g and followed by ΣHCH, ranging from 0.73 ng/g to 60.97 ng/g with a mean value of 24.06 ng/g. Dieldrin, endrin, HCB and α-endosulfan were also found in soils with less than 15 ng/g. Ratios of p,p'-(DDD DDE)/DDT in soils under three land usages were: paddy field ＞ tree land ＞ fallow land, indicating that land usage inlfuenced the degradation of DDT in soils. Ratios of p,p'-(DDD DDE)/DDT ＞1, showing aged residues of DDTs in soils of the Taihu Lake region. The results were discussed with data from a former study that showed very low actual concentrations of HCH and DDT in soils in the Taihu Lake region, but according to the chemical half-lives and their concentrations in soils in 1980s, the concentration of DDT in soils seemed to be underestimated. In any case our data show that the ban on the use of HCH and DDT resulted in a tremendous reduction of these pesticide residues in soils, but there are still high amounts of pesticide residues in soils, which need more remediation processes.     

Alterations of organ histopathology and metallolhionein mRNA expression in silver barb, Puntius gonionotus during subchronic cadmium exposure

Common silver barb,Puntius gonionotus,exposed to the nominal concentration of 0.06 mg/L Cd for 60 d,were assessed for histopathological alterations(gills,liver and kidney),metal accumulation,and metallothionein(MT)mRNA expression.Fish exhibited pathological symptoms such as hypertrophy and hyperplasia of primary and secondary gill lamellae,vacuolization in hepatocytes,and prominent tubular and glomerular damage in the kidney.In addition,kidney accumulated the highest content of cadmium,more than gills and liver.Expression of MT mRNA was increased in both liver and kidney of treated fish.Hepatic MT levels remained high after fish were removed to Cd-free water.In contrast,MT expression in kidney was peaked after 28 d of treatment and drastically dropped when fish were removed to Cd-free water.The high concentrations of Cd in hepatic tissues indicated an accumulation site or permanent damage on this tissue.