PAH Levels and Profiles in the Suspended Particulate Matter in Zagreb through Four Seasons

This paper presents the analysis of polycyclic aromatic hydrocarbons (PAHs) measured in all four seasons in suspendedparticulate matter (SPM) collected with a high-volume sampler on one measuring site in the northern part of Zagreb. About 30 samples of SPM were analysed for each season, including workdays and weekends and there were no differences amongst them. The concentrations of all PAHs were highest in winter andlowest in summer. The spring PAH concentrations were lower thanthe autumn ones, as the spring had more sunny and warm days. Theprofiles of PAH/BaP at the measurement sites showed that the mainsource of PAHs in spring and summer was traffic while asubstantial amount of autumn and winter PAHs, besides traffic,came from heating.     

金昌市不同季节大气颗粒物的传输路径和潜在源分析

选取金昌市2019年3月-2020年2月PM2.5和PM10逐小时观测数据,分析该市颗粒物污染水平的季节差异,并利用HYSPLIT后向轨迹模式和GDAS气象数据,分析不同气流轨迹对金昌市颗粒物浓度的影响及不同季节颗粒物的潜在污染来源.结果表明,2019年金昌市冬季PM2.5污染最严重,春季PM10污染严重;春、秋季PM...     

南通市PM2.5中水溶性离子季节分布特征

对南通市2016年12月-2018年10月大气污染季节分布特征进行了分析。结果表明,南通市ρ(PM2.5)和ρ(水溶性离子)为冬、春季高,夏、秋季低。春夏秋冬四季ρ(水溶性离子)占ρ(PM2.5)百分比分别为68.2%,70.6%,64.5%和74.5%,其中二次离子SNA(NO3-、SO42-和NH4+)占ρ(PM2.5)的百分比分别为63.1%,67.0%,59.3%和66.8%;ρ(NO3-)/ρ(SO42-)表明,移动源已成为南通市春、秋、冬季的主要污染源,四季均存在不同程度的二次转化,且SO2的转化率均大于NO2,NO2冬季转化率最大、夏季最小,SO2夏季转化率最大、秋季最小。南通市NO2转化为硝酸盐的主要形式是气相均相反应,非均相反应和均相反应对SO2转化为硫酸盐的贡献差异不大。     

燃煤工业城市大气细颗粒物中水溶性无机离子的季节变化特征及来源解析——以邯郸市为例

为探究典型燃煤工业城市邯郸市的大气细颗粒物(PM2.5)污染水平及水溶性无机离子特征,于2016年1—12月采集了当地大气PM2.5样品,然后利用离子色谱法测得水溶性无机离子的组分,分析了不同季节水溶性无机离子随PM2.5的浓度变化特征。通过对PM2.5中的阴离子、阳离子进行分析发现,SO4^2-、NO3^-和NH4^+在春夏秋冬四季均为PM2.5中的主要离子成分,SO4^2-、NO3^-和NH4^+的浓度之和在春夏秋冬四季占各季节总的水溶性无机离子浓度的百分比分别为84.6%、77.4%、89.9%、62.5%。其中,在春季和冬季含量最高的3种离子分别是NO3^-、SO4^2-和NH4^+,夏季含量最高的3种离子分别是SO4^2-、NH4^+和NO3^-,而秋季含量最高的3种离子分别是NH4^+、SO4^2-和NO3^-。相关性分析发现,2016年春季、夏季和秋季PM2.5为酸性,冬季为碱性。SO4^2-、NO3^-、NH4^+浓度分析表明,冬季PM2.5中的一次建筑扬尘排放较多。通过主成分分析法得出,PM2.5中水溶性无机离子主要来源于二次转化和生物质燃烧。     

Statistical analysis of arsenic contamination in drinking water in a city of Iran and its modeling using GIS

In this research, probable arsenic contamination in drinking water in the city of Ardabil was studied in 163 samples during four seasons. In each season, sampling was carried out randomly in the study area. Results were analyzed statistically applying SPSS 19 software, and the data was also modeled by Arc GIS 10.1 software. The maximum permissible arsenic concentration in drinking water defined by the World Health Organization and Iranian national standard is 10 μg/L. Statistical analysis showed 75, 88, 47, and 69% of samples in autumn, winter, spring, and summer, respectively, had concentrations higher than the national standard. The mean concentrations of arsenic in autumn, winter, spring, and summer were 19.89, 15.9, 10.87, and 14.6 μg/L, respectively, and the overall average in all samples through the year was 15.32 μg/L. Although GIS outputs indicated that the concentration distribution profiles changed in four consecutive seasons, variance analysis of the results showed that statistically there is no significant difference in arsenic levels in four seasons.     

太阳山湿地浮游植物优势功能群季节演替特征及驱动因子分析

为探明太阳山湿地浮游植物优势功能群季节演替规律及其主要驱动因子,于2019年4月(春季)、7月(夏季)、10月(秋季)和2020年1月(冬季)采样分析了太阳山湿地浮游植物的种类组成、优势种、丰度、生物量及季节变化,同时测定了水环境理化因子指标,采用冗余分析方法研究了浮游植物优势功能群的优势度、丰度与水环境因子之间的关系。结果表明:太阳山湿地浮游植物可分为22个功能类群;优势功能群的季节演替和空间分异特征明显,存在一定的规律性。春、秋、冬3个季节的浮游植物以硅藻门为主,夏季以绿藻门和蓝藻门为主。春季优势功能群主要为D、C、P,以硅藻门种类为主;夏季优势功能群主要为J、Lo、TC、M、H1,以硅藻门、绿藻门、蓝藻门种类为主;秋季优势功能群主要为D、S1、MP,以硅藻门、绿藻门种类为主;冬季优势功能群主要为D、X3,以硅藻门种类为主。影响太阳山湿地浮游植物优势功能群季节演替的水环境因子有水温(WT)、pH、溶解氧(DO)、透明度(SD)、盐度(Sal)、氮磷营养元素含量、化学需氧量(COD_Cr)和高锰酸盐指数(COD_Mn)。4个湖区浮游植物优势功能群的时空差异与水环境因子密切相关,其中,西湖区浮游植物优势功能群的季节演替驱动因子为pH、DO、WT、总磷(TP),东湖区为pH、DO、WT、氮磷营养元素含量,南湖区为pH、DO、COD_Cr、五日生化需氧量(BOD₅),小南湖区为pH、DO、WT、BOD₅、COD_Cr、TP。pH、DO、WT、BOD₅、SD等水环境因子的季节差异以及TP、TN、氨氮(NH₃-N)、COD_Mn等水环境因子的湖区差异是太阳山湿地浮游植物优势功能群出现季节演替的主要原因。     

Indoor and outdoor concentrations of PM2.5 trace elements at homes, preschools and schools in Stockholm, Sweden

Fine particles (PM2.5) were sampled indoors and outdoors at 40 sampling sites; in ten classrooms in five schools, at ten preschools and 20 non-smoking homes, in three communities in Stockholm, Sweden, during nine 2-week periods. Each sampling site was sampled twice, once during winter and once during spring. The samples were analysed for elemental concentrations using X-ray fluorescence (XRF) spectroscopy. In all locations significantly higher outdoor concentrations were found for elements that are related to long-range transported air masses (S, Ni, Br and Pb), while only Ti was higher indoors in all locations. Similar differences for S, Br and Pb were found in both seasons for homes and schools. In preschools different seasonal patterns were seen for the long-range transported elements S, Br and Pb and the crustal elements Ti, Mn and Fe. The indoor/outdoor ratios for S and Pb suggest an outdoor PM2.5 particle net infiltration of about 0.6 in these buildings. The community located 25 km from the city centre had significantly lower outdoor concentrations of elements of crustal or traffic origin compared with the two central communities, but had similar levels of long-range transported elements. Significant correlations were found between PM2.5 and most elements outdoors (rs = 0.45-0.90). Copper levels were found to correlate well (rs = 0.64-0.91) to the traffic marker NO2 during both winter and spring in all locations. Copper may be a suitable elemental marker for traffic-related aerosols in health studies in areas without other significant outdoor Cu sources.     

阅海湿地叶绿素a季节变化特征及其与环境因子的关系

2020年春、夏、秋、冬四季对阅海湿地进行水样采集并测定叶绿素a(Chl-a)等10种环境因子,采用相关分析、逐步回归分析和通径分析进行分析评价。结果表明：阅海湿地深水区与浅水区的Chl-a质量浓度季节差异较大,夏、秋季较高,春、冬季较低;空间上深水区高于浅水区。对深水区Chl-a质量浓度影响的环境因子依次为水温、I_Mn、DO,其中水温为正向直接作用,I_Mn、DO为负向直接作用;对浅水区Chl-a质量浓度影响的环境因子依次为TP、BOD₅,均为正向直接作用。TN对阅海湿地Chl-a质量浓度影响不大,控制水体含磷营养盐类物质及有机物的输入量是防止阅海湿地Chl-a质量浓度过高的主要措施。     

Long-term variations of water quality parameters in the Maroon River, Iran

Sixteen water quality parameters have been monitored at four stations located along the Maroon River during 1989?C2008. The trend analysis was performed on seasonal and annual time-scales using the Mann?CKendall test, the Sen??s slope estimator and the linear regression. The relationships of the water quality parameters to river discharge were also investigated. The statistical methods showed both positive and negative trends in annual water quality data. However, significant trends were detected by the statistical methods only in calcium, magnesium, sodium absorption ratio, pH, and turbidity series. The results indicated that the concentrations of the water quality parameters increased in spring and winter seasons, while the concentrations were diluted in summer and autumn seasons in the last two decades. Moreover, the highest numbers of significant trends were found in the spring and summer series, respectively. According to the regression analysis, most of the water quality parameters were negatively correlated with river discharge.     

Columnar aerosol optical and radiative properties according to season and air mass transport pattern over East Asia

The column-integrated optical and radiative properties of aerosols in the downwind area of East Asia were investigated based on sun/sky radiometer measurements performed from February 2004 to June 2005 at Gwangju (35.23° N, 126.84° E) and Anmyeon (36.54° N, 126.33° E), Korea. The observed aerosol data were analyzed for differences among three seasons: spring (March-May), summer (June-August), and autumn/winter (September-February). The data were also categorized into five types depending on the air mass origin in arriving in the measurement sites: (a) from a northerly direction in spring (S(N)), (b) from a westerly direction in spring (S(W)), (c) cases with a low ?ngstr?m exponent (<0.8) in spring (dust), (d) from a northerly direction in autumn/winter (AW(N)), and (e) from a westerly direction during other seasons (AW(W)). The highest ?ngstr?m exponents (α) at Gwangju and Anmyeon were 1.43?±?0.30 and 1.49?±?0.20, respectively, observed in summer. The lowest column-mean single-scattering albedo (ω) at 440 nm observed at Gwangju and Anmyeon were 0.89?±?0.02 and 0.88?±?0.02, respectively, during a period marked by the advection of dust from the Asian continent. The highest ω values at Gwangju and Anmyeon were 0.95?±?0.02 and 0.96?±?0.02, respectively, observed in summer. Variations in the aerosol radiative-forcing efficiency (β) were related to the conditions of the air mass origin. The forcing efficiency in summer was -131.7 and -125.6 W?m(-2) at the surface in Gwangju and Anmyeon, respectively. These values are lower than those under the atmospheric conditions of spring and autumn/winter. The highest forcing efficiencies in autumn/winter were -214.3 and -255.9 W?m(-2) at the surface in Gwangju and Anmyeon, respectively, when the air mass was transported from westerly directions.     

A Season-dependent Variation of Genotoxicity of Surface Water Samples from Taihu Lake, Yangzte Delta

The present study is to assess a year round change of genotoxicity of surface water in Taihu Lake, Yangtze delta. The water samples were collected in spring, summer, autumn and winter of 2001, respectively. The bacterial L-arabinose resistance forward mutation test (ara test), along with the Ames test, was performed for the evaluation of time profile of mutagenicity of the surface water samples. The strong genotoxic potentials were detected in the near-shore area, especially in the vicinity to the major city. All the samples collected from the lake center and areas distant from dense human activity showed genotoxicity-free in year round time. Intensified human activity along the lake may play an important role for the genotoxic pollution. By comparison of the samples from year round, the winter samples showed the strongest mutagenic potential of all seasons, which indicates that meteorological and hydrological factors also affect the water quality. The impact of dense human activity, improper management and season change should be put into consideration for designing an effective remediation project in the lake basin area.     

Determination of heavy metal contents in some freshwater fishes

The concentrations of heavy metals in tench, pike-perch, and common carp fish caught in four different seasons from Damsa dam lake (Nev?ehir) were determined. Heavy metal contents of fishes changed depending on seasons. The highest Al (20.894 mg/kg) in tench was established in winter, and the lowest Al (1.605 mg/kg) was determined in summer. Fe content of tench fish changed between 112.906 mg/kg (autumn) and 31.207 mg/kg (spring). In addition, Zn contents of tench were found between 36.0323 mg/kg (summer) and 430.586 mg/kg (winter). The results indicate that concentrations of Cu of tench varied from 0.1934 mg/kg (winter) to 15.422 mg/kg (autumn). Results indicate that concentrations varied from 2.923 mg/kg (autumn) to 32.078 mg/kg (summer) with a mean of 11.1893 mg/kg for Al; 0.2483 mg/kg (spring) to 3.3088 mg/kg (autumn) with a mean of 1.6189 mg/kg for Ni; 0.5325 mg/kg (spring) to 0.845 mg/kg (autumn) with a mean of 0.7234 for Pb; and 7.0464 mg/kg (winter) to 253.686 mg/kg (summer) with a mean of 133.6348 for Zn. In common carp, Al, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Zn, Se, Ga, and Te contents were determined as 3.9623 mg/kg; 0.1293, 0.2336, 0.0526, 0.1543, 4.2406, 0.726, 1.797, 0.6216, 6.8536, 0.1783, 0.7876, and 0.371 mg/kg in autumn, respectively.     

2008年北京市PM_(10)的粒度分布分形维数变化特征

2007年11月-2008年10月间在北京市市中心和西北城区采集了不同季节的PM10样品,并借助扫描电子显微镜和图像分析软件对其进行粒度分布分形维数分析。结果表明,颗粒物中细颗粒物越多,粒度越细,则颗粒物粒度分布分形维数值越大。2008年西北城区的PM10的粒径分布分形维数较大,市中心的较小。市中心的粒度分布分形维数在1.95～2.59之间,各个季节的分形维数呈现冬季春季夏季秋季,西北城区的粒度分布分形维数在2.58～2.72,各个季节的分形维数呈现秋季夏季冬季春季,说明在市中区冬季PM10粒度较细,而在西北城区秋季的颗粒物偏细。与2005年同季相比,2008年的总体颗粒物和烟尘集合体的粒径分布分形维数较大,矿物颗粒的粒度分布分形维数较小,并且总分布的季节变化一致。2008奥运期间的PM10粒度分布分形维数在2.28～3.39之间变化,标志着颗粒物总体变细的趋势。     

东平湖浮游动物对南水北调东线运行的时空响应

东平湖是南水北调东线工程输水线路下游的最后一个调蓄湖泊.为探究调水后的东平湖浮游动物时空响应,于2016—2017年对东平湖浮游动物进行了涵盖春(4月)、夏(7月)、秋(10月)、冬(1月)的4次调查,共检出浮游动物3类72种(属),其中,轮虫51种(70.83％)、枝角类11种(15.28％)、桡足类10种(13.8...     

重庆某工业园土壤重金属污染特征、风险及源解析

以重庆市某工业园区表层土壤为研究对象,探讨了土壤重金属在不同季节的污染特征,利用污染指数法、健康风险模型和主成分/绝对主成分得分受体模型进行风险评价和源分析。结果表明:不同季节土壤样品间各重金属含量差异显著。35.5%的样品中汞含量超出土壤污染风险筛选值,其他元素未超标。与土壤背景值相比,各元素表现出不同程度的富集,汞超标约110~1300倍。内梅罗指数显示土壤整体和汞元素处于轻度污染及以下,其他元素为安全。潜在生态危害指数显示,土壤整体和汞属于极强污染,镉属于轻微~强污染,其他元素为轻微污染。土壤重金属总致癌风险为2.6×10^-7~1.0×10^-5,总非致癌风险熵均小于1,砷存在致癌风险,主要通过经口摄入暴露。秋季中,汞、六价铬、铅、镍、砷和铜来自工业源,镉主要来源于自然成因。春季中,镉和铅来自交通、冶金和燃煤等排放,镍、砷和铜源于冶炼和金属表面处理等排放,汞主要来自化工生产和燃料燃烧。交通运输、工业生产和燃料燃烧等污染的排放是土壤重金属的主要来源,今后应加强园区内汞、砷和镉的源头减排和治理。     

川东北中心城市南充大气污染态势及其主要成因

基于南充市主城区6项大气污染物浓度数据,研究了2014-2020年南充市的空气质量指数、空气质量指数等级和首要污染物的时序分布。结果表明:随着大气污染防治的开展,南充市大气污染物浓度逐渐下降,出现首要污染物的天数逐年减少,空气质量逐步提高。受污染物节律性影响,空气质量呈现明显的季节差异,冬季空气质量最差,春季次之,夏季污染相对较轻,秋季最轻。首要污染物类型的季节分布特征表现为冬季出现首要污染物天数最多,春季和夏季次之,秋季最少。春、秋、冬季以PM_2.5污染为主,夏季以O₃污染为主。从全年来看,与O₃相比,PM_2.5对空气质量的影响更为突出。在持续控制大气污染物排放总量的同时,精细化协同管控细颗粒物、氮氧化物、挥发性有机物和二氧化硫排放将有助于现阶段的大气污染防治。     

秦山岛海域大型底栖动物群落结构的季节变化

于2015—2016年在秦山岛海域开展4个航次的大型底栖动物调查,用优势度指数法和多样性指数法对底栖动物优势种和多样性状况进行评价。结果显示,四季共采集鉴定底栖动物7门69种,其中环节动物25种,软体动物19种,节肢动物16种,棘皮动物3种,脊索动物、纽形动物和腔肠动物各2种;优势种共14种。大型底栖动物种数和密度均值均为春季＞秋季＞夏季＞冬季,生物量均值为夏季＞冬季＞春季＞秋季,密度和生物量的空间分布无明显规律。多样性评价结果表明,秦山岛海域底栖动物群落受到轻度干扰,底栖环境处于轻度污染状态;除人为干扰和环境因子外,种间关系及生活史特征也是影响底栖动物群落结构变化的重要因素。     

基于ＧＩＳ的乌鲁木齐市ＮＯ２ 时空分布特征

以乌鲁木齐市2008-2012年7个空气自动监测点位小时浓度数据为基础数据，利用ArcGIS 技术，分析了其NO2年变化、月变化、日变化、空间分布等污染特征。结果表明，NO2年均值为0．065～0．068 mg/m3，基本保持稳定；NO2呈明显的季节变化，冬季污染较重，春节、秋季次之，夏季空气质量相对较好；NO2呈现“单峰型”的日变化特征，夜间NO2明显高于白天；不同季节 NO2的空间分布特征不同，与交通、供暖、人口密度、地理位置密切相关；NO2分布与风速相关关系明显，而与气温、湿度的关系为非线性。     

青藏高原典型高寒森林地带CH4浓度特征分析

基于波长扫描光腔衰荡光谱线监测系统在海螺沟国家大气背景站(以下简称海螺沟站)开展甲烷(CH_4)连续自动监测,通过局部近似回归法进行背景值筛分分析。结果表明:2016、2017年海螺沟站CH_4年均体积分数和筛分的背景体积分数接近,两者浓度水平与北半球中纬度地区全球本底站CH_4浓度水平相当;海螺沟站CH_4能够代表背景区域浓度水平。海螺沟站CH_4体积分数呈春、夏季低,秋、冬季高特征,季节变化主要受到特定的地理环境和大气环流的影响,大气环流占主导影响。夏季CH_4体积分数最低但日振幅最大,与高原高海拔背景下森林地带的辐射对流引起局地扩散作用有关。采用逐步逼近回归筛分CH_4监测数据,海螺沟站CH_4背景季浓度变化和北半球中高纬度地区其他背景站大气CH_4的季节变化特征以及CH_4季体积分数振幅基本一致。背景站四季的CH_4载荷贡献在16个风向分布结果表明,在春、夏季存在西风带下南亚方向污染物气团的远距离输送;青藏高原东部近地面在冬季处于反气旋冷高压控制下,而SSW方向风向能够短暂打破这种稳定的气象条件,污染物得到迅速扩散,SSW为负贡献。     

杭州城区大气颗粒物污染特征及PM2.5潜在源区研究

基于2015年9月1日至2016年8月25日杭州城区观测点PM₁、PM_2.5、PM₁₀小时浓度数据进行分析，利用HYSPLIT模型、潜在源贡献因子（PSCF）方法和浓度权重轨迹（CWT）方法，探讨了杭州城区PM₁、PM_2.5、PM₁₀时间分布特征和PM_2.5潜在来源。结果表明：研究期间PM₁季节平均浓度表现为冬季 > 秋季、春季 > 夏季，PM_1~2.5、PM_2.5~10浓度则表现为冬季 > 春季 > 秋季 > 夏季；PM₁浓度日变化呈现明显的双峰现象，而PM_1~2.5和PM_2.5~10在同一时段均无明显浓度峰值；杭州城区PM_2.5受外源输送污染具有明显的季节性变化特征，夏季、秋季杭州城区PM_2.5的潜在源区主要是浙江北部、安徽东南部等，春季PM_2.5的潜在源区主要是浙江中部、江苏南部等，冬季PM_2.5的潜在源区主要是山东南部、江苏西南部、浙江北部、安徽南部、江西中部等地区。