沧州市大气污染特征观测研究

利用沧州2009年7月～2011年7月的NOx(NOx=NO+NO2)、O3、SO2以及PM10的观测数据,分析了沧州市大气污染物的日变化、月平均变化、年变化以及季节平均变化特征.结果表明,NOx、PM10日变化为双峰型,O3为单峰.SO2日变化也呈现为双峰型,但是其变化幅度较平缓.NO、NO2、NOx、SO2有较相同的季节变化趋势.NO、NO2、NOx、SO2及PM10冬季值最大,分别为(30.0±18.9)μg·m-3、(50.5±19.8)μg·m-3、(80.5±38.7)μg·m-3、(62.1±34.7)μg·m-3、(201.6±98.5)μg·m-3.臭氧夏季浓度最高,其月均值为(88.0±22.3)μg·m-3.NO、NO2、NOx、O3、SO2及PM10年均值分别为(18.9±14.5)μg·m-3、(37.6±13.0)μg·m-3、(56.5±27.5)μg·m-3、(49.9±16.3)μg·m-3、(31.6±19.5)μg·m-3、(156.7±79.1)μg·m-3.秋冬季污染物主要为NOx(NOx=NO+NO2)、SO2以及PM10,夏季污染物主要为O3.     

2010年广州亚运期间空气质量与污染气象条件分析

利用2010年11月4日～12月10日广州地区NO2、O3、SO2、PM、能见度实测资料,区域空气污染指数RAQI及大气输送扩散特征参数,分析广州亚运期间空气质量与气象条件变化特征.结果表明,亚运期间空气质量比亚运前后好,能见度比亚运前后大,PM1和PM2.5浓度比亚运前后小,能见度与PM1和PM2.5有较好的反相关;亚运期间NO2和SO2日均值和小时均值均达到国家一级标准,PM10日均值和O3小时均值均满足国家二级标准,污染物得到较好的控制;广州地区SO2受本地源和外地源远距离输送叠加影响,NO2受本地源影响较大;广州周边城市NO2、SO2和PM10有向广州输送的潜势,而广州O3有向其周边城市扩散的潜势;亚运期间污染气象条件比亚运前后有利,亚运期间污染物浓度降低得益于政府实施的减排措施及良好的气象条件.     

南京地区典型霾天气个例特征的比较分析

利用2011年南京大学城市大气环境观测站气象因子及污染物浓度资料、58238站点气象探空资料及NCEP再分析资料、CALIPSO卫星资料,比较分析了南京地区4类典型霾天气(烟花爆竹、沙尘、秸秆燃烧及不利气象条件污染)的污染特征.结果表明:烟花爆竹个例污染物排放集中,以细颗粒物为主,除夕和初五的PM2.5小时浓度分别达到0.46 mg·m-3和0.34 mg·m-3,受逆温层影响,能见度持续降低,最低达到1.16 km;受北方沙尘暴南下影响,沙尘个例以粗颗粒为主要污染物,PM10小时最高浓度为0.78 mg·m-3,PM2.5/PM10平均值为0.39,粒子形状不规则,体积偏退比为0.17;秸秆燃烧个例为重霾污染,能见度最低值为0.97 km,后向散射系数为0.0039 km-1獉sr-1,PM10和PM2.5最高小时浓度达到0.80 mg·m-3和0.49 mg·m-3,颗粒物主要来自南京东南地区秸秆的集中燃烧;不利气象条件导致的污染过程在冬季比较常见,下沉气流活跃,出现双层逆温,近地面静小风造成污染物积累,PM2.5与能见度的相关系数达到0.86,细颗粒物为主要污染物.可见,南京市霾天气可分为两类,分别是由不利气象条件导致的累积性污染和由高强度排放源造成的暴发性污染,具有不同的气象和污染特征.     

春季华东高山背景区域PM2.5和PM2.5~10中水溶性无机离子特征

为了探讨华东高山背景区域春季颗粒物中水溶性组分的特征,2014年3月至5月在国家大气背景监测福建武夷山站采集PM2.5及PM2.5~10样品,获取了水溶性无机离子组分,并同步收集气象因子及SO2、NO2、O3、PM10和PM2.5等污染物质量浓度数据.结果表明,春季武夷山背景点PM2.5和PM2.5~10中水溶性无机离子总浓度分别为(8.3±2.8)μg·m-3和(1.3±0.9)μg·m-3,分别占PM2.5和PM2.5~10质量浓度的(43.7±7.5)%和(24.4±6.4)%.SO2-4占PM2.5质量浓度百分比最高,为(32.4±6.3)%;NO-3占PM2.5~10质量浓度百分比最高,为(8.9±3.7)%.春季武夷山背景点硫酸盐主要存在于细颗粒物中,且以(NH4)2SO4和K2SO4的形式存在,粗颗粒中的硝酸盐则主要以Mg(NO3)2的形式存在.春季武夷山背景点水溶性无机离子主要来源于沙尘、海盐及高污染区域的远距离输送.     

成都市区夏季大气污染物浓度时空变化特征分析

为了解成都市区大气污染物浓度水平及其变化规律,统计分析了2013年6月1日—8月31日3个市区站点(十里店、梁家巷和草堂寺)SO2、NO2、O3、PM2.5、PM10和CO逐时观测资料.结果表明,观测期间O3污染严重,上述3个站点小时均值超标率分别达22%、37%和42%.大气颗粒物污染也较为严重,上述3个站点PM10日均浓度超标率分别为13%、8%和3%,而PM2.5日均值超标率分别高达34%、27%和26%.NO2和CO早晚的浓度高峰主要与机动车流量增加和混合层高度降低有关.由于紫外辐射影响,O3浓度在正午出现峰值.受机动车流量高峰和气象条件的影响,PM2.5和PM10最大值和最小值分别出现在上午和下午.通过对污染物"周末效应"的分析,发现周末O3、PM2.5和PM10的浓度显著高于工作日,SO2、NO2和CO反之.成都市区大气污染受局地排放和外源输送共同影响,其中PM10和NO2主要受局地源控制,而PM2.5、SO2和O3受外输送影响较大.     

秦皇岛大气污染物浓度变化特征

为了解河北沿海旅游城市秦皇岛大气污染现有水平,研究其变化趋势,于2009年9月～2010年8月对秦皇岛市大气中的典型污染物进行连续监测研究.结果表明,该市大气中NO、NO2、SO2、O3和PM10平均浓度分别为（18±18）、（45±18）、（42±46）、（44±25）和（128±77）μg·m-3,PM10污染最为严重,年均浓度超出国家二级标准（100μg·m-3）接近30%.夏季O3日平均浓度和日小时浓度最大值（O3₁h max）的平均分别为（64±21）μg·m-3和（126±42）μg·m-3,偏南海洋气团有加重O3污染现象,伴随有短期超标;采暖期大气NOx、SO2和PM10分别是非采暖期的1.5、4.9和1.5倍,PM10和SO2日均值相对国家二级标准的超标率分别为53%和11%.京津冀、环渤海工业区的气团输送和当地海港区高排放叠加可使秦皇岛NOx、SO2和PM10污染物平均浓度上升17%、27%和12%,冬季其三者大气平均浓度飙升至（100±49）、（110±84）和（215±108）μg·m-3.北方内陆干洁气团和南方海洋气团可有效清除秦皇岛市大气污染物.     

夏秋季石家庄大气污染变化特征观测研究

研究了石家庄夏秋季节大气污染状况及2008奥运前后大气污染物浓度变化特征.2007和2008年夏秋季节,使用全自动在线观测仪器对石家庄大气环境质量进行连续监测,目的是阐明奥运期间石家庄污染物减排对当地大气环境的改变,探讨石家庄地区产生的大气污染物对北京及周边地区可能的影响.结果表明,除了氮氧化物,其他污染物均有超标情况出现,其中夏秋季节O3浓度较高,小时最大浓度值平均(O3-Max)分别为(177.2±63.0)和(105.8±61.7)μg·m-3,NO和NO2在夏秋季节的浓度分别为(4.5±4.0)、(32.7±12.4)μg·m-3和(21.5±16.9)、(60.5±16.9)μg·m-3,SO2浓度分别为(72.0±27.5)和(92.0±44.4)μg·m-3,PM2.5和PM10浓度达到(102.3±47.6)、(153.3±58.3)μg·m-3和(95.8±50.0)、(147.4±67.0)μg·m-3;奥运期间各类污染物浓度显著下降,NOx、O3-Max、SO2、PM2.5和PM10浓度分别为(43.8±15.0)、(142.0±54.9)、(52.4±18.8)、(76.7±35.1)和(116.5±38.8)μg·m-3,其中SO2、PM2.5和PM10分别较2008年监测期间平均值降低34.6%、22.8%和21.0%.本研究系统分析了夏秋季节石家庄大气污染状况,为评估当地大气污染控制措施提供了科学依据.     

长三角地区秸秆焚烧污染物排放清单及其在重霾污染天气模拟中的应用

根据2008年长三角地区江苏、安徽、浙江3省各地级市及上海市水稻、小麦、玉米、油菜4种农作物的年产量,结合谷草比、秸秆焚烧比例及排放因子建立了长三角地区秸秆焚烧大气污染物排放清单.结果表明：长三角地区秸秆焚烧产生的PM10、PM2.5、SO2、NOx、CO、EC、OC分别为36.8×104、14.4×104、1.5×104、9.2×104、20.8×104、2.6×104、12.2×104t.秸秆焚烧污染物排放量较大的区域主要集中在江苏中北部和安徽北部.在区域大气环境模拟系统RegAEMS中考虑秸秆焚烧源的影响,针对2008年10月底江苏一次重霾污染天气事件进行模拟,发现考虑秸秆焚烧源后模拟结果有较大的改善.秸秆焚烧可以导致区域PM10、CO浓度上升30%以上,黑碳和有机物的消光贡献明显增强.区域输送研究表明,苏中地区、外省秸秆焚烧排放源对此次重霾污染的贡献分别达到32.4%、33.3%.     

复合型工业城市重空气污染过程大气污染特征

以湘潭市地区2013年10月29日一次重空气污染过程为例,利用湘潭市空气自动监测站24小时连续监测数据,研究此次重空气污染过程大气污染浓度变化特征。结果表明SO2、NO2、PM10、CO、O3和PM2.5的日均值分别为105 ug/m3、117 ug/m3、542 ug/m3、2.583mg/m3、146 ug/m3、419 ug/m3,PM2.5污染最为严重,其日均浓度超出国家二级标准(75 ug/m3)4.59倍。SO2、NO2、PM10、CO、O3和PM2.5日变化显著,SO2和O3的日变化均呈单峰型,PM10、PM2.5、CO和NO2日变化均呈早晚双峰型。通过调查研究,这次污染事件的主要原因有极端不利的气象条件,近郊区大量焚烧秸秆以及PM2.5的区域污染传输。     

南京3类不同大气污染过程下气溶胶水溶性无机离子的特征研究

为了探讨不同大气污染过程下气溶胶中水溶性离子组分的差异,分析比较了2009年10月16～30日持续污染、2010年4月27～30日沙尘污染、2010年6月14日秸秆焚烧污染这3次污染过程中气溶胶（PM10、PM2.1和PM1.1）及主要水溶性离子（NH4＋、Mg2＋、Ca2＋、Na＋、K＋、NO2-、F-、NO3-、Cl-、SO24-）质量浓度及其谱分布.结果发现,3次污染过程中气溶胶污染严重,PM2.1/PM10比值有明显区别,其中沙尘污染过程最低,平均值仅为0.27;秸秆焚烧过程最高,为0.7.持续污染过程中NO3-和SO24-浓度较高,总阴离子质量浓度占PM10、PM2.1和PM1.1的18.62%、32.92%和33.53%.沙尘污染过程使气溶胶中的不溶物增加,总水溶性离子组分减少,仅占PM10、PM2.1和PM1.1的13.36%、23.72%和28.54%,而Ca2＋质量浓度高于其他时期,且主要分布在〉1μm粒径段上.秸秆焚烧过程中各种水溶性无机离子质量浓度均高于其他时期,但在气溶胶中比例较低;示踪物K＋明显高于其他过程.3次污染过程中NO3-、SO24-和NH4＋质量浓度峰值均在0.43～0.65μm粒径段.     

Effects of two sludge application on fractionation and phytotoxicity of zinc and copper in the soil

The potential harm of heavy metals is a primary concern in application of sludge to the agricultural land. A pot experiment was conducted to evaluate the effect of two sludges on fractionation of Zn and Cu in soil and their phytotoxicity to pakchoi. The loamy soil was mixed with 0%, 20%, 40%, 60% and 80% (by weight) of digested sewage sludge (SS) and composted sludge (SC). The additions of both sludges caused a significant raise in all fractions, resulting in that exchangeable (EXCH) and organic bound (OM) became predominance of Zn and organic bound Cu occupied the largest portion. There was more available amount of Zn and Cu in SS treatments than SC treatments. During the pot experiment, the concentration of Zn in EXCH, carbonate (CAR) and OM and Cu in EXCH and OM fractions decreased in all treatments, so their bioavailability reduced. Germination rate and plant biomass decreased when the addition rate was high and the best yield appeared in 20% mixtures at the harvest of pakchoi. The two sludges increased tissue contents of Zn and Cu especially in the SS treatments. Zn in pakchoi was not only in relationship to ΔEXCH and ΔCAR forms but also in ΔOM forms in the sludge-soil mixtures. Tissue content of Cu in pakchoi grown on SC-soils could not be predicted by ΔEXCH. These correlation rates between Zn and Cu accumulation in pakchoi and variation of different fractions increased with time, which might indicate that sludges represented stronger impacts on the plant in long-term land application.     

Intraspecific differences in effects of co-contamination of cadmium and

A hydroponic experiment was carried out to study intraspecific differences in the effects of different concentrations of cadmium (Cd)(0-10 mg/L) and arsenate (As(V)) (0-8 mg/L) on the growth parameters and accumulation of Cd and As in six wheat varieties Jing-9428, Duokang-1, Jingdong-11, Jing-411, Jingdong-8 and Zhongmai-8. The endpoints of wheat seedlings, including seed germination,biomass, root length and shoot height, decreased with increasing the Cd and As concentrations. Significant differences in seed germination, biomass, root length, shoot height and the accumulation of Cd and As were observed between the treatments and among the varieties (p ＜ 0.05). The lethal dosage 50% were about 20, 80, 60, 60, 80 and 20 mg As/L for Jing-9428, Duokang-1, Jingdong-11,Jing-411, Jingdong-8 and Zhongmai-8, respectively, and the corresponding values for Cd were about 30, 80, 20, 40, 60 and 10 mg Cd/L, respectively. Among the six varieties, Duokang-1 was found to be the most resistant to Cd and As toxicity, and Zhongmai-8 was the most sensitive to Cd and As co-contamination. The resistance of the six varieties was found dependant on the seedling uptake of Cd and As. Duokang-1 was the most suitable for cultivation in Cd and As co-contaminated soils.     

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.     

EDTA-enhanced phytoremediation of lead contaminated soil by Bidens maximowicziana

Phytoremediation is a potential cleanup technology for the removal of heavy metals from contaminated soils.Bidens maximowicziana is a new Pb hyperaccumulator,which not only has remarkable tolerance to Pb but also extraordinary accumulation capacity for Pb.The maximum Pb concentration was 1509.3 mg/kg in roots and 2164.7 mg/kg in overground tissues.The Pb distribution order in the B. maximowicziana was:leaf>stem>root.The effect of amendments on phytoremediation was also studied.The mobility of soil Pb and the Pb concentrations in plants were both increased by EDTA application.Compared with CK(control check),EDTA application promoted translocation of Pb to overground parts of the plant.The Pb concentrations in overground parts of plants was increased from 24.23-680.56 mg/kg to 29.07-1905.57 mg/kg.This research demonstrated that B.maximowicziana appeared to be suitable for phytoremediation of Pb contaminated soil,especially,combination with EDTA.     

Distribution and ecological effect of mercury in Laogang landfill, Shanghai, China

Laogang landfill near Shanghai is the largest landfill in China, and receives about 10000 t of daily garbage per day, Samples of topsoil and plants were analyzed to evaluate mercury pollution from the landfill. For topsoil samples, there were significant correlations among total mercury （HgT）, combinative mercury （Hgc） and gaseous mercury （HgG）, and content of total organic carbon （TOC）, but, no significantly relationship was found between Hg content and filling time. Hg content changes in vertical profiles with time showed that the average Hgv of profiles 1992, 1996, and 2000 was similar, but their average HgG was quite different. HgT was significantly correlated with Hgc in profile 1992 and 2000, and Hgv was significantly correlated with Hg6 in profile 1996. HgG/Hgv ratio in profile samples decreased in the order of （HgG,/HgT）1992〉（HgG/HgT）1996〉〉（HgG/HgT）2000. A simple outline of Hg release in landfill could be drawn： with increasing of filling time, degradation undergoes different biodegradation, accordingly, gaseous mercury goes through small, more, and small proportion to total mercury. Distribution of Hg in plants was inhomogeneous, following the order of leaf〉root〉stem. The highest value of leaf may be associated with higher atmospheric Hg from landfill. Ligneous plants （e.g. Phyllostachys glanca, Prunus salicina and Ligustrum lucidum） are capable of enriching more Hg than herbaceous plants.     

Enzymatic oxidation of aqueous pentachlorophenol

The influence of the nonionic surfactant Tween 80 on pentachlorophenol （PCP） oxidation catalyzed by horseradish peroxidase was studied. The surfactant was tested at concentrations below and above its critical micelle concentration （CMC）. Enhancement of PCP removal was observed at sub-CMCs. The presence of Tween 80 in the reaction mixture reduced enzyme inactivation which occurred through a combination of free radical attack and sorption by precipitated products. A simple first-order model was able to simulate time profiles for enzyme inactivation in the presence or absence of Tween 80. At supra-CMCs, the surfactant caused noticeable reductions in PCP removal, presumably through micelle partitioning of PCP which precluded the hydrophobic PCP molecule from interacting with the enzyme.     

Decomposition of alachlor by ozonation and its mechanism

Decomposition and corresponding mechanism of alachlor, an endocrine disruptor in water by ozonation were investigated. Results showed that alachlor could not be completely mineralized by ozone alone. Many intermediates and final products were formed during the process, including aromatic compounds, aliphatic carboxylic acids, and inorganic ions. In evoluting these products, some of them with weak polarity were qualitatively identified by GC-MS. The information of inorganic ions suggested that the dechlorination was the first and the fastest step in the ozonation of alachlor.     

基于综合水质标识指数和对应分析法的校园河道水质评价

以三峡大学的校园河道求索溪为研究对象,利用综合水质标识指数法确定求索溪水质类别,分析其水质时空变化规律,并利用对应分析法得出求索溪中不同监测点的主要污染因子.研究结果表明:求索溪整体的综合水质标识指数为7.423,整体水质为劣V类(地表水环境质量标准GB 3838-2002)且黑臭.从时间变化来看,求索溪4月份的水质最差,5月份次之,4、5月份所有监测点的水质都劣于V类且黑臭;8月份水质最好,水质为Ⅳ类;从空间分布来看,8个监测点综合水质标识指数均超过6.0,水质为劣V类,其中6号监测点的水质相对最好,监测点3号的水质相对最差;对应分析法得出求索溪的整体水体污染程度受总氮因子的影响最大,其次为总磷.该研究拟为求索溪及类似校园河道的水环境治理研究提供基础依据和参考.     

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.