淄博市区大气颗粒物重金属元素分布特征及其来源分析

为科学认识淄博市区大气颗粒物污染状况,探讨颗粒物的污染水平和元素在颗粒物中的分布与分配特征,对颗粒物中元素的来源进行分析。于2015年冬季和夏季期间分别布设45个和16个采样点采集悬浮颗粒物（TSP）、PM₁₀及PM_2.5样品,分析了颗粒物和18种元素（或化合物）的质量浓度。结果表明：1）大气颗粒物中冬季TSP、PM₁₀及PM_2.5的质量浓度均值高于夏季;PM₁₀和PM_2.5质量浓度均超过国家标准,其中冬季PM_2.5质量浓度是标准限值的1.96倍。2）不同粒径的颗粒物中元素质量分数差别显著,As、Cd、Cr、Cu、Ni、Pb、Zn等多数重金属元素主要富集在PM_2.5中,且PM_2.5约占PM₁₀的65%（冬季）和73%（夏季）。3）颗粒物PM_2.5中Al₂O₃、CaO、Fe₂O₃、K₂O、MgO等氧化物主要受土壤扬尘控制;As、Cd、Hg、Pb、Se、Zn等元素主要源于人为污染;Se的富集因子最高,反映了PM_2.5污染主要来源于燃煤;Co、Cu、Ni、Na₂O受土壤扬尘和人类活动的共同作用,而Cr具有混合污染的特点。     

北京市大气PM2.5中多溴联苯醚污染水平与来源分析

2008年1月、9月和10月在北京城区5个采样点共采集9个大气颗粒物PM_2.5样品。遵循US EPA-1614方法,采用同位素稀释、高分辨气相色谱/高分辨质谱(HRGC/MS)联用技术,测定了大气颗粒物PM_2.5样品中14种多溴联苯醚(PBDEs)的质量浓度,研究了北京市城区大气颗粒物PM_2.5中多溴联苯醚的污染水平、分布特征及来源。结果表明: 9个大气颗粒物PM_2.5样品中PBDEs的质量浓度范围为2.82~57.94 pg/m³,平均值为15.67 pg/m³,BDE-209的质量浓度为0.34~7.32 pg/m³,PM_2.5样品中PBDEs的质量浓度冬季高于秋季;高溴代联苯醚在颗粒物中的含量高,低溴代联苯醚的含量低;交通源对大气颗粒物PM_2.5中PBDEs的污染贡献值很小,工业污染源贡献大于交通源,从含有溴代阻燃剂的物品释放到大气中的PBDEs对大气颗粒物PM_2.5中PBDEs的污染贡献值最大。     

四川盆地西北盆缘城市气溶胶污染特征

本文以四川盆地西北盆缘的广元、绵阳、德阳、成都、雅安为研究对象,探究2015~2019年5大城市空气质量及大气气溶胶污染特征变化规律,以期为深入揭示四川盆地城市大气气溶胶污染特征提供参考。通过对环境监测站实时数据,使用SPSS21.0软件进行数据分析得出成都、德阳、绵阳3城市因人为污染贡献较大和四川盆地封闭的地形的原因导致的PM_2.5、PM₁₀、NO₂、O₃污染相对较重,雅安、广元因人为污染贡献小、有利于污染物扩散的风向因而空气质量良好。整体上PM_2.5、PM₁₀、SO₂、NO₂均表现为夏季低、冬季高,而O₃具有相反的季节变化特征。SO₂、NO₂、PM_2.5、PM₁₀与相对湿度、降水量、平均气温均呈负相关关系,而与平均气压呈正相关关系。     

萍乡市春节前后空气质量及气溶胶的碳、氮同位素组成特征

为探讨萍乡市元旦至元宵期间空气质量变化情况及其中PM_2.5及PM₁₀中的碳、氮来源,2017年1月1日至2月16日在萍乡市进行了在线空气质量监测,采集了PM_2.5、PM₁₀滤膜气溶胶样品并进行了总氮(TN)、总碳(TC)浓度以及δ¹⁵N、δ¹³C组成。结果表明,采样期间空气的PM_2.5浓度为(82.45±43.04)μg/m^3;PM₁₀、SO_2和NO_2浓度分别为(112.98±68.66)μg/m^3、(23.85±14.32)μg/m^3和(32.68±14.4)μg/m^3。样品的PM_2.5和PM₁₀的TN、TC浓度分别为(9.73±5.99)μg/m^3、(12.68±9.53)μg/m^3和(15.15±7.9)μg/m^3、(18.7±9.11)μg/m^3,δ¹⁵N、δ¹³C分别为6.32‰±4.11‰、6.89‰±4.44‰和-25.1‰±0.89‰、-25.55‰±1.25‰。在元旦和春节期间,发生了空气污染事件,元旦期间平均PM_2.5、PM₁₀、NO_2和SO_2浓度均高于春节期间,推断元旦污染事件可能是由气象条件导致污染物聚集所引起,而春节污染事件可能是由烟花爆竹燃放释放的SO_2和大量的颗粒物进入大气所致。采样期间和两个空气污染事件的δ¹⁵N和δ¹³C组成相似,其主来源均可能为机动车尾气和煤燃烧排放及部分C_3植物燃烧。     

成都市东郊TSP及Pb、Cd、Hg、As 浓度日变化规律研究

采用大流量采样器,2003年春季(4月18日阴天,5月6日晴天)对成都市东郊大气颗粒物进行了研究．测定颗粒物浓度和Pb、Cd、Hg、As浓度。结果表明．成都市东郊大气颗粒物污染严重,TSP超标率达50％。TSP浓度及Pb、Cd、Hg、As浓度日变化规律呈“双峰型”．浓度峰值出现在5：00～9：00．17：00～21：00两个时段,其变化原因与人类活动和生产活动、大气对流活动和湍流活动、降雨等因素有关。应引起足够重视。     

新冠疫情减排时期河南省大气污染物分布及健康效应研究

由新冠(COVID-19)疫情引发的全国性大封锁为研究大规模工业减排对大气污染的影响提供了契机。对河南省2020年疫情前、封锁期间及逐步复工复产期间与2019年同期6种主要大气污染物(PM_2.5、PM₁₀、CO、NO₂、SO₂与O₃)的时空差异开展对比分析,运用基于健康风险的空气质量指数(HAQI)法,研究河南省主要大气污染物的健康效应。结果表明,河南省大气污染物分布整体呈现北部高南部低的空间变化特征,PM_2.5受一次污染和二次污染影响较显著。减排初期(春节疫情期间),除NO₂浓度迅速减少外,其他污染物没有明显变化, PM_2.5浓度比2019年同期增加15%,是不利的气象条件与大气氧化度增加促进二次化学过程的结果。春节后疫情期间, PM_2.5浓度迅速降低至疫情前的50%左右,为2019年同期的50%左右。基于HAQI结果,研究期间(冬–春)影响河南省大气健康效应的关键因素是PM_2....     

Variation and dispersal of PM10 and PM2.5 during COVID-19 lockdown over Kolkata metropolitan city,India investigated through HYSPLIT model

The higher concentration of PM₁₀ and PM_2.5 in the lower atmosphere is severely harmful for human health and it also makes visibility diminution along with weather and climate modifications.The main objective is to find out the spatiotemporal variation and dispersal of PM₁₀ and PM_2.5 along with COVID-19 infection in the dusty city Kolkata.The consecutive two years PM₁₀ and PM_2.5 data of different stations have been obtained from State Pollution Control Board,Govt.of West Bengal.Forward trajectory analysis has been done through HYSPLIT(Hybrid Single Particle Lagrangian Integrated Trajectory)model to find the path and direction of air particles.The result showed that the various meteorological or environmental factors(such as temperature,relative humidity,wind,wind speed,pressure and gusty wind)and geographical location regulate the spatiotemporal variation of PM₁₀ and PM_2.5.These factors like high temperature with relative humidity and strong wind influence to disperse the particulate matters from north to south direction from city to outside during summer in Kolkata metropolitan city.During summer(both pre and lockdown years),the height of particles is extended up to 1000 m owing to active atmospheric ventilation whereas in winter it is confined within 100 m.The HYSPLIT model clearly specified that the particles dispersed from south,south-west to north and north east direction due to strong wind.The constant magnification of PM₁₀ and PM_2.5 in the lower atmosphere leads to greater frequency of COVID-19 infections and deaths.In Kolkata,the one of the crucial reasons of high infection and deaths(COVID-19)is co-morbidity of people.     

北京市冬季大气PM2.5中多氯联苯的污染水平与分布

2008年1月同时采集了北京市市区/交通干道(中国地质大学(北京)东门及测试楼顶)、工业区(首钢集团焦化厂、高井热电厂)和背景点(十三陵)大气颗粒物PM_2.5样品。依据US EPA 1668A 方法,采用同位素稀释、高分辨率气相色谱/高分辨率质谱(HRGC/MS)联用技术,对比分析了PM_2.5中19种多氯联苯(PCBs)的质量浓度、分布特征及来源。结果表明, 5个采样点PM_2.5的质量浓度范围为101.85～145.57 μg/m³,日均值为119 μg/m³,比美国1997年制定的日均标准(65 μg/m³ )高83%,属严重污染。 PM_2.5中∑PCBs的质量浓度和毒性当量(TEQ)分别为7.2～16.2 pg/m³ (平均值10.9 pg/m³)、8.29～17.81 fgWHO-TEQ/m³ (平均值13.58 fgWHO-TEQ/m³),与其他国家和地区比较,北京市大气PCBs的污染处于较低水平。PCBs最高浓度出现在工业区,其次是市区,背景点最低,化石燃料的不完全燃烧是北京市PCBs的主要来源。研究成果将为北京市大气环境中持久性有机污染物(POPs)的污染防治提供科学依据。      

Hemolysis of PM10 on RBCs in vitro:An indoor air study in a coal-burning lung cancer epidemic area

Epidemiological studies have suggested that inhalation exposure to indoor ambient air from coal-burning environments is causally associated with respiratory health risks.In order to explore the toxicological mechanisms behind the adverse health effects,the hemolytic activity of PM₁₀(particulate matter with an aerodynamic diameter of 10 um or less)samples collected from homes burning coal in the recognized China"cancer village"Xuanwei were evaluated and matched against their trace elemental contents.The results demonstrated that the hemolytic activity of indoor PM₁₀ in coal-burning environments ranged from 4.28%to 5.24%,with a clear positive dose-response relationship.Although low dose samples exhibited a reduced hemolytic activity,PM₁₀ could have a toxic effect upon people in a coal-burning indoor environment for extended time periods.The concentrations of analyzed trace elements in PM₁₀ samples ranged from 6966 to 12,958 ppm.Among the analyzed elements,Zn,Ti,Ni,Cu,Pb,Ba,Mn,Cr and V were found at higher concentrations and accounted for over 95%of the total elements.The concentrations of total analyzed elements in the PM₁₀ samples revealed a significant positive correlation with PM₁₀ hemolytic activity.Of the analyzed elements,Zn,Pb and Cs positively correlated with hemolysis,while Li,U and V negatively correlated with the hemolysis of human red blood cells(RBCs).Therefore,the heavy metal elements could be one of the main factors responsible for the hemolytic capacity of indoor PM₁₀ in coal-burning environments.     

襄樊—广济断裂带东段构造变形特征及其演化

襄樊—广济断裂带是分隔大别造山带和扬子板块北缘前陆褶皱逆冲带的边界断裂,其几何学、运动学及构造演化特征记录了南北两大不同性质的大地构造单元发生碰撞、拼贴及相互作用的地质过程。在野外调查、构造解析和年代学研究基础上,结合区域地质和地球物理资料分析,认为襄樊—广济断裂带东段以深部向南逆冲、浅表向北逆冲的“鳄鱼嘴式”对冲构造为特征,与西段的构造变形样式和次序存在显著差异。中扬子地区东部受控于江南—雪峰造山带和大别造山带南北两大构造体系,深部扬子板块北缘向大别造山带之下俯冲导致造山带自北向南挤出,推覆构造可影响至瑞昌一带,由南向北的浅层逆冲推覆可影响至梅川附近,二者在襄樊—广济断裂带东段的蕲春—武穴—浠水一带对接。襄樊—广济断裂带经历了印支早期同碰撞由北向南的逆冲推覆和深层次的韧性剪切变形(T₂末)、燕山早—中期双向对冲构造变形(J_1-3)、燕山晚期伸展正断层变形(K_1-2)、喜山早期由北向南小规模逆冲变形(E₁)阶段。     

西宁市逆温特征及其与空气污染物浓度的相关分析

根据2010-2012年西宁市基本探空气象站逐日07：00时和19：00时两个时次的逆温资料,及西宁市环境监测站监测的大气污染物（SO₂、NO₂、PM₁₀）日均值数据,分析了西宁市逆温基本特征及其与空气污染物浓度之间的相关关系. 结果表明：西宁市2010-2012年07：00时逆温出现频率为69%,19：00时逆温出现频率为41%;近地逆温层厚度冬季最厚,夏季最薄. 07：00时和19：00时月平均逆温厚度变化趋势基本一致;西宁市逆温发生频率冬半年明显高于夏半年;秋、冬季产生的逆温强度明显比春、夏季强. 3 a来西宁市空气污染共出现148 d,逆温频率和空气污染物月平均浓度有较好的正相关性. 08：00时西宁市逐日空气污染物浓度与逆温厚度呈正相关,与逆温强度呈负相关关系. 冬、春季平均空气污染物浓度值与逆温厚度、强度均呈正相关关系.     

Elements’ Geochemical Characteristics of PM10 and PM2.5 in Beijing During Winter and Spring

From 2012 to 2013, heavy haze frequently hit Beijing in spring and winter. The fine atmospheric particulates can be inhaled by people, and remain in the respiratory tract and lung for quite a long time. The heavy metal elements in the particles are harmful, and even carcinogenic to human bodies. Therefore, it is necessary to master the geochemical characteristics and the temporal and spatial distribution of the heavy metal elements in atmospheric particles. The atmospheric particulates (TSP/PM₁₀/PM_2.5) were collected by using TH1500C intelligent medium volume (80~120 L/min) air samplers in the five functional areas and suburbs of Beijing, respectively in January 2013 (heating period) and April 2013 (non-heating period). The five functional areas were: building materials factory area, residential area, education area, business area and recreation area, each functional area having three sampling sites, and five in suburbs. The sampling height was 1.5 m above the ground and the distance of the sampling sites to roads exceeded 50 m so as to avoid excessive impact of vehicle exhaust emissions. These samples were analyzed by Inductively Coupled Plasma-Mass Spectrometry (ICP-MS), Inductively Coupled Plasma Optical Emission Spectrometer(ICP-OES)and Atomic Fluorescence Spectrometer (AFS), by which 21 elements including Al, Fe, Mn, As, Hg, Cd, Cr were tested. Based on the comparisons of the concentration and element content variation of atmospheric particulates of these functional areas in and after the heating period, the spatial distribution of atmospheric particulates and the influence of coal combustion on the concentration and composition of atmospheric particulates were revealed. The elements sources of atmospheric particulates were also discussed by computing the enrichment factor of the elements, providing a scientific basis for the air contaminant treatment in Beijing. The results showed that the total concentration of the 21 elements of PM₁₀ and PM_2.5 in the functional areas of Beijing in winter was higher than that in spring, the most marked among them being the business area. In winter, the concentration of pollution elements in the building materials factory area and the business area in Beijing was extremely high, and the residential area, education area, recreation area and suburbs where people live were much better, among which the education area was the best. The concentration change of particulates in suburbs was quite smaller in winter and spring than that of the urban area. It also showed that the concentrations of Cd, Cr, As and Hg in PM₁₀ increased by 233%,306%,298%,141%,respectively and the increase in PM_2.5 was 442%、309%、310%、256%, respectively. These abovementioned elements show a tendency to accumulate mainly in PM_2.5 whose concentrations in winter were significantly higher than those in spring. It indicates that coal heating during winter makes great contributions to the polluting elements in atmosphere and the main polluting particulates are Cd, As and Hg.     

离子色谱法测定冰川末端大气PM2.5可溶性离子及其来源解析

为了研究祁连山西段冰川末端地区大气PM_2.5细粒子中可溶性无机离子组分的变化特征,于2011年采集了一批大气PM_2.5的Telfon滤膜样品,并应用离子色谱对可溶性离子进行了分析。样品采用超纯水超声萃取各种水溶性离子,优化的萃取溶液体积为25 mL,萃取时间为30 min,萃取液用0.45μm纤维滤膜过滤,各种离子在一定浓度范围内线性关系良好,相关系数r>0.999。所测样品的阴阳离子中,SO₄^2-、NO₃^-、Ca²⁺、和NH₄⁺的质量浓度约占到水溶性离子总量的88%。可溶性离子浓度呈现出春夏高、秋冬低的季节变化特征,夏季可溶性离子浓度最高。     

长春市城区近地表灰尘粒度特征及其环境意义

为剖析长春市城区近地表灰尘粒度特征,分别沿南北和东西轴线采集了34件城市近地表灰尘样品,采用激光粒度仪对样品进行了粒度测试分析。结果表明：长春市近地表灰尘颗粒物平均中值粒径和算术平均粒径分别为21.58 μm和24.24 μm,分选极差;以粗粉粒（10.00～80.00 μm）为主,平均约占71.28%,黏粒组（<5.00 μm）和细粉粒组（5.00～10.00 μm）分别约占14.75%和13.05%。频率曲线呈正偏双峰型分布,峰态中等偏窄,与现代尘暴和城市街道灰尘分布特征相一致,反映出其起源的多元性和相对稳定性,表明近地表灰尘沉积仍是风积作用的继续。近地表灰尘颗粒物粒径均小于100.00 μm,极易在外动力条件下再次扬起并悬浮搬运,PM₁₀和PM_2.5所占比例分别为27.76%和7.32%,其生态环境效应不应被忽视。粒径分布无显著空间变化,但城市中心区域粒径变化范围小,这可能说明城市边缘区域较中心区域近地表灰尘的起源更具多源性和复杂性。     

Comparisons of annual ambient air pollutant concentrations and dry deposition flux variations for day and nighttime in middle Taiwan

This study monitored ambient air particles and the metallic elements Cu, Cr, Cd, Pb, and Zn in total suspended particulate (TSP) concentrations and dry deposition during the day and nighttime sampling period at a traffic sampling site in central Taiwan from 2012 March to 2013 February. The dry deposition flux ratios and seasonal concentration variations of ambient air particles and these metallic elements are also discussed. The results indicate that for all the elements, except for Zn, the highest average concentrations in TSP occurred in the spring and summer, while the lowest average was in the fall and winter for both day and nighttime sampling periods.     

资源型城市景观生态风险的时空分异:以乌海市为例

为探究大型露天煤矿开采对西北干旱荒漠区景观生态风险的影响,以及资源型城市转型背景下的时空动态,以资源衰退型的内蒙古自治区乌海市及周边县域为研究区,结合现有景观生态风险评价中的干扰度、脆弱度指标,增加受威胁指数来综合构建资源型城市景观生态风险评价框架。基于乌海市2005—2015年景观类型数据,从时间和空间上分析景观生态风险及其动态。结果显示:(1)2010—2015年景观类型之间转移相较于2005—2010年更剧烈,年变化强度分别为7.43%和3.44%,工矿用地与城市建设用地最活跃,但年增加强度减小。(2)林地、水域和湿地损失度先略增加后大幅度减小,其他土地和草地损失度呈增加趋势,工矿用地先减小后略增加;城市建设用地和工矿用地受威胁指数最大,其余类型的景观受威胁指数均有上升趋势,但其他土地、水域和湿地增加趋势逐渐减慢。(3)2005—2015年景观生态风险指数升高,空间分布总体呈西、中部高而南北低的格局,而不同等级风险区表现为低风险区由边缘向中心转移,而高风险区依托原有高风险区扩展。研究期风险区变化显著的是西部沙地高风险区,矿区东部其他土地因周围分布灌丛和草地,风险始终低于西部其他土地。根据不同风险等级中工矿用地的面积占比情况,将工矿用地占比控制在5%以内可达到控制总体景观生态风险的目的。研究为资源型城市通过合理的景观配置进行生态风险管控提供了依据。     

温度对青藏高原高寒灌丛CO2通量日变化的影响

应用涡度相关技术连续监测的CO₂通量及温度数据(2003年1月1日至2004年12月31日),分析了青藏高原高寒灌丛净生态系统CO₂交换(NEE)日变化与温度之间的关系.结果表明:1)在暖季夜间(21:00至次日06:00时)温度与NEE变化呈显著正相关关联,而白昼(07:00~20:00时)NEE变化与温度无显著关联;2)在冷季不论夜间还是白昼,NEE变化均与温度密切相关,温度是决定冷季高寒灌丛生态系统CO₂交换的主要因素.在全球气候变暖背景下,青藏高原气候变化呈现出冬季增温率明显高于春、夏季特征,未来气候变暖导致的增温效应可能会加速青藏高原高寒灌丛生态系统CO₂排放,使其作为碳汇的能力而减弱.     

天山乌鲁木齐河源冰川积雪化学特征及其季节变化

高海拔雪冰可以记录源自于地球表面的各种化学物质信号.从2002年9月到2005年10月3年的时段内,在天山乌鲁木齐河源1号冰川积累区采集积雪样品,运用比较法、相关分析法等方法,对其中主要离子、不溶粉尘、痕量金属和δ18O等特征及其季节变化进行了分析研究.分析结果表明,积雪离子浓度大小顺序依次为:Ca2+＞SO₄2-＞NO₃-＞Cl-＞NH₄+＞Mg2+＞Na+＞K+,其中Ca2+是主要的阳离子,SO₄2-是主要的阴离子.离子相关性分析表明,除NO₃-之外,其他离子浓度之间均存在较好的正相关.积雪中δ18O值随时间变化表现出与大气温度变化相反的规律.积雪中不溶粉尘和主要化学离子浓度具有明显的季节变化特征,春季期间浓度明显高于其他季节,表明沙尘活动对冰川区化学物质输入有较大贡献;此外,痕量金属(Cd、Pb、Zn、Al、Fe)季节变化特征表明,人类活动的污染物对于研究区雪冰中的化学特征亦有重要影响.