利用大气超级站对乌鲁木齐市一次沙尘天气过程及组份的分析

本研究利用大气超级站对乌鲁木齐市4月9日至10日沙尘天气过程,粒径谱、离子和重金属组成及变化进行分析.研究结果表明激光雷达观测结果与环境空气质量监测基本一致;小粒径颗粒在沙尘和非沙尘时段含量最多,但在沙尘时段大粒径颗粒的增长幅度远大于小粒径;沙尘过程中的离子主要来源于土壤一次源;沙尘过程中地壳元素浓度及占比均显著升高,...     

夏季桂林市大气PM_(2.5)化学组成和成分分布的质谱研究

选取桂林市5个代表性监测点,采用单颗粒气溶胶飞行时间质谱仪在线分析该市夏季大气PM_(2.5)的化学组成及化学成分分布。结果表明:5个监测点,80%的PM_(2.5)分布在0.2μm~1.0μm的小粒径范围,20%的PM_(2.5)分布在1.0μm~2.5μm大粒径范围;大气PM_(2.5)中离子成分包含Na~+、K~+、NH~+4、C2H3~+/Al~+、Fe~+、HSO~-_4、NO~-_3、NO~-_2、CNO~-、CN~-、SO~-_3、O~-和元素碳离子;PM_(2.5)中离子按成分特征可分为元素碳、有机碳、元素碳有机碳混合颗粒、富锰颗粒、富铁颗粒、富钾颗粒、矿物质、左旋葡聚糖以及其他金属等9类,各监测点元素碳占比均超过50%;元素碳与硫酸盐、铵盐、硝酸盐发生内混合的程度极高,其中各监测点元素碳与硫酸盐混合程度最高,均达到90%左右。     

合肥市春季大气PM10和PM2.5中碳组分的污染特征

选取桂林市5个代表性监测点,采用单颗粒气溶胶飞行时间质谱仪在线分析该市夏季大气PM2.5的化学组成及化学成分分布。结果表明： 5个监测点,＞80%的PM2.5分布在0.2 μm～1.0 μm的小粒径范围,＜20%的PM2.5分布在1.0 μm～2.5 μm大粒径范围; 大气PM2.5中离子成分包含Na+、K+、NH+4、C2H3+/Al+、Fe+、HSO-4、NO-3、NO-2、CNO-、CN-、SO-3、O-和元素碳离子; PM2.5中离子按成分特征可分为元素碳、有机碳、元素碳有机碳混合颗粒、富锰颗粒、富铁颗粒、富钾颗粒、矿物质、左旋葡聚糖以及其他金属等9类,各监测点元素碳占比均超过50%; 元素碳与硫酸盐、铵盐、硝酸盐发生内混合的程度极高,其中各监测点元素碳与硫酸盐混合程度最高,均达到90%左右。     

桂林市细颗粒物部分典型排放源的粒径谱及成分分析

采用在线单颗粒气溶胶质谱技术源解析方法,对桂林市PM2.5典型排放源的粒径和化学成分进行质谱分析,采集燃煤/燃气源、工业工艺源、扬尘源、油烟源4类共计7个典型排放源。结果表明,桂林市4类排放源细颗粒物的粒径分布为0.25~1.25μm,80%以上的细颗粒分布在0.2~1.0μm的小粒径范围,峰值约0.68μm。细颗粒物离子成分含有Na~+、Mg~+、K~+、NH~+4、Fe~+、Pb~+、Cd~+、V~+、Mn~+、Li~+、Al~+、Ca~+、Cu~+、Zn~+、Cr~+、CN~-、PO_3~-、NO_2~-、NO_3~-、Cl~-、SO_4~(2-)、SiO_3~-等成分,桂林市细颗粒物为元素碳、有机碳元素碳、有机碳、富锰颗粒、富铁颗粒、富钾颗粒、矿物质、左旋葡聚糖以及其他金属等9类。     

武汉地区沙尘天气气溶胶粒径分布特性研究

通过利用湖北省大气复合污染自动监控预警中心的振荡天平法颗粒物监测仪、光散射法气溶胶粒径谱仪,对武汉地区一次典型沙尘天气过程中记录的不同粒径气溶胶颗粒数量浓度、相对质量浓度进行研究。结果表明,在武汉地区沙尘天气过程中,粗颗粒显著增多,而细颗粒显著减少,这与部分研究发现的沙尘天气过程中粗颗粒与细颗粒共同显著增多的结论有所不同。粒径谱仪分析显示,大于PM5颗粒的增多对粗颗粒浓度增加有显著贡献,而小于PM0.5颗粒的减少则对细颗粒浓度降低有主要贡献,这可能是武汉地区沙尘天气过程颗粒物的变化特点。     

广州市春季一次沙尘天气过程综合观测

2017年4月21—23日广州市经历了一次远距离传输的沙尘天气过程,为了解沙尘过程对广州市空气质量的影响,基于广州市大气超级站,利用单颗粒气溶胶质谱(SPAMS)、气溶胶激光雷达观测数据并结合HYSPLIT后向轨迹模型分析了沙尘过程细颗粒物组分及污染来源贡献变化和沙尘气溶胶的来源及路径。结果表明:受沙尘过境影响,PM_(10)浓度大幅升高,PM_(2.5)/PM_(10)最小值仅为12.1%;沙尘过境期间影响近地面颗粒物的沙尘高度主要分布在1 km以下区域,近地面颗粒物消光系数均值为100.11 Mm~(-1),探测到最大退偏振比为0.28。SPAMS研究发现沙尘过境期间含硅酸盐颗粒物(SI)的细颗粒物数浓度比例达25.9%,是沙尘过境前的1.4倍;PM_(2.5)中扬尘贡献率明显增大,达到了17.3%,是沙尘过境前的1.9倍。后向轨迹模型HYSPLIT显示此次沙尘为典型的北方沙尘传输,沙尘源自中国西北地区,传输方向为自西北输送至华东地区后,转为东南方向影响广州市。     

合肥市冬季灰霾天气PM_(2.5)源解析

于2016年12月30日—2017年2月4日,利用单颗粒气溶胶飞行时间质谱仪(SPAMS),对合肥市PM_(2.5)开展来源解析连续监测,共捕捉到4次较为明显的灰霾过程,对颗粒物种类及质谱特征进行了分析。结果显示,监测期间合肥市主要颗粒物成分为元素碳(EC)(31. 9%)、富钾(K)(16. 6%)、有机碳(OC)(16. 0%)及混合碳颗粒(ECOC)(15. 0%)等。主要污染源为机动车尾气源(24. 5%)、工业工艺源(22. 7%)、燃煤源(14. 1%)、二次无机源(13. 5%)等。污染天气发生时,工业工艺源占比上升2. 2个百分点,生物质燃烧和燃煤源占比分别下降1. 7和2. 7个百分点,机动车尾气和扬尘源基本持平,表明此次污染过程主要受到工业工艺源的累积影响。     

基于大气超级站观测的2017年5月北京市沙尘天气过程分析

结合常规污染物监测、PM_2.5化学组分监测、激光雷达监测和颗粒物数浓度及粒径监测等手段,对2017年5月影响北京市的一次沙尘天气过程进行分析。结果表明：5月4日凌晨起沙尘天气开始影响北京市,延庆、官园和通州3个站点PM₁₀峰值浓度分别为2 091、2 245、2 590 μg/m³,体现了该次沙尘天气影响程度之重。PM_2.5浓度与PM₁₀变化一致,也达到重度污染的水平。沙尘天气移动路径是沿着区域西北至东南方向。沙尘天气主体从3 km左右的高空进入北京市,随后逐渐渗透至1 km高度以及地面,且沙尘层厚度较高,覆盖了地面至3 km的高度。沙尘天气过程中OM和Ca²⁺组分增幅最大。在沙尘天气影响严重时间段,沙尘天气源与生物质燃烧源比例之和大于50%,最高值为67.6%。沙尘天气过程中颗粒物峰值粒径为0.965~1.037 μm。     

单颗粒本地排放源谱在上海新冠感染防控期间的监测应用

采用单颗粒飞行时间质谱分析上海市2022年3月—5月新冠感染防控期间大气颗粒物来源,重点关注移动排放源的时空分布规律,并对防控期间、春节期间和防控前正常生产生活期间的监测结果做比对分析。结果表明,防控期间细颗粒物质量浓度较春节期间和正常生产生活时段下降了23.3%;受防控减排措施影响明显的移动源、扬尘、燃煤和工业工艺源排放的细颗粒物质量浓度相较另外两个时段都有不同程度的降低。     

影响泰州市空气质量的几种沙尘类型分析

利用2020年11月—2021年5月泰州市大气颗粒物自动监测数据,结合激光雷达观测资料、气象资料及后向轨迹模式,研究分析不同类型沙尘天气过程对泰州市空气质量的影响。结果表明,研究时段泰州市受到沙尘天气影响共计12次,影响天数21 d,污染天数占比达42.9%;按照影响时长和影响程度将沙尘天气过程分为直接影响型、移速缓慢型、边缘影响型、入海回流型等4种类型;由于天气形势背景和传输路径差异,不同类型沙尘对泰州市空气质量影响程度差异较大,整体而言,移速缓慢型沙尘、入海回流型沙尘对泰州市空气质量影响更为显著。     

Topsoil and Housedust Metal Concentrations in the Vicinity of a Lead Battery Manufacturing Plant

The aim of the study was to determine the extent of heavy metal pollution in the vicinity of a lead battery manufacturing plant in the Czech Republic, both in the general environment and within homes. Topsoils (0–5 cm) were sampled from 100 sites along 4 transects which crossed the battery factory, the town centre and outlying rural areas. Housedust samples were collected from 15 plant-workers' homes and 15 non plant-workers' homes located at various distances from the factory. Samples were analysed for levels of Pb, Zn, Cd, Cu, As and Sb, using ICP-AES. Soil concentrations of Pb, Cd, As and Sb peaked at the perimeter fence of the battery factory with Pb levels of up to 12 650 g g> ^-1. Concentrations of these metals decreased exponentially within 500 m of the plant. Whilst the battery factory does appear to be a source of all the metals with the exception of Zn, emissions do not appear to be transported to any great extent over distances of more than 0.5 km. Topsoil and housedust concentrations of Pb, Zn, Cd, Cu, As and Sb in the general Mlada Boleslav area do not appear to be significantly different from those recorded in a large scale survey of urban soils in the United Kingdom. A comparison of housedust Pb concentrations in homes of plant workers and non-plant workers suggests that there may be a small input of Pb into the home environment by battery plant employees.     

微波消解-原子吸收光度法测定土壤中铜锌铅镉镍铬

用微波消解－原子吸收光度法测定土壤中铜，锌，铅，镉，镍和铬。通过硝酸－氢氟酸－过氧化氢体系消解液对土壤样品消解，选择出微波最佳消解条件。对硝酸－盐酸－过氧化氢体系消解液和硝酸－氢氟酸－过氧化氢体系消解液进行消解对比试验，发现前者不能将土壤样品完全消解，后者能将样品消解完全，但需将消解液中剩余的酸赶尽，否则测定结果将明显偏低。微波消解土壤与传统电热消解相比，操作简便快速，可提高工作效率。     

An Overview of Contaminant-Related Issues Identified by Monitoring in San Francisco Bay

The San Francisco Estuary Regional Monitoring Program for Trace Substances (RMP) began in 1993 and is sponsored by 74 local, state, and federal agencies and companies through their discharge or Bay use permits. The RMP monitors water, sediment, toxicity, and bivalve bioaccumulation at 25 sites in the Bay that are considered to represent "background" conditions. Several major environmental issues have been identified by the RMP. Polychlorinated biphenyls and mercury were often above water quality guidelines, and often occurred in fish tissues above U.S. Environmental Protection Agency (U.S. EPA) screening values. Concentrations do not appear to be decreasing, suggesting continuing inputs. Episodes of aquatic toxicity often occurred following runoff events that transport contaminants into the Bay from urbanized and agricultural portions of the watershed. Sediment toxicity occurred throughout the Bay, and has been correlated with concentrations of specific contaminants (chlordanes, polynuclear aromatic hydrocarbons) at some locations; mixtures of contaminants were probably also important. Since the RMP does not monitor all ecosystem components, assessments of the overall condition of the Bay cannot be made. However, in terms of contamination, the RMP samples suggest that the South Bay, and North Bay sites are moderately contaminated.     

Biomagnification factors (fish to Osprey eggs from Willamette River,Oregon, U.S.A.) for PCDDs,PCDFs, PCBs and OC pesticides

A migratory population of 78 pairs of Osprey (Pandion haliaetus) nesting along the Willamette River in westernOregon was studied in 1993. The study was designed to determinecontaminant concentrations in eggs, contaminant concentrationsin fish species predominant in the Ospreys diet, andBiomagnification Factors (BMFs) of contaminants from fish specieseaten to Osprey eggs. Ten Osprey eggs and 25 composite samplesof fish (3 species) were used to evaluate organochlorine (OC)pesticides, polychlorinated biphenyls (PCBs), polychlorinateddibenzo-p-dioxins (PCDDs), and polychlorinated dibenzofurans(PCDFs). Mercury was also analyzed in fish. Geometric meanresidues in Osprey eggs were judged low, e.g., DDE 2.3 g g^-1 wet weight (ww), PCBs 0.69 g g^-1, 2,3,7,8-TCDD 2.3 ng kg^-1, and generally well below known threshold values for adverse effects on productivity, and the population was increasing. Osprey egg residue data presentedby River Mile (RM) are discussed, e.g., higher PCDDs were generally found immediately downstream of paper mills and eggsfrom the Willamette River had significantly elevated PCBs and PCDDs compared to reference eggs collected nearby in the CascadeMountains. Prey remains at nest sites indicated that the Largescale Sucker (Catostomus macrocheilus) and NorthernPikeminnow (Ptychocheilus oregonensis) accounted for an estimated 90.1% of the biomass in the Osprey diet, and composite samples of these two species were collected from different sampling sites throughout the study area for contaminant analyses. With the large percentage of the fishbiomass in the Osprey diet sampled for contaminants (and fisheaten by Ospreys similar in size to those chemically analyzed),and fish contaminant concentrations weighted by biomass intake, a mean BMF was estimated from fish to Osprey eggs for the largeseries of contaminants. BMFs ranged from no biomagnification(0.42) for 2,3,7,8-TCDF to 174 for OCDD. Our findings for themigratory Osprey were compared to BMFs for the resident HerringGull (Larus argentatus), and differences are discussed. Webelieve a BMF approach provides some basic understanding ofrelationships between contaminant burdens in prey species offish-eating birds and contaminants incorporated into their eggs,and may prove useful in understanding sources of contaminants inmigratory species although additional studies are needed.     

The Draft of the New German Guideline VDI 3782/8 to Model Automobile Exhaust Dispersion

The draft of the German guideline to calculate automobile exhaust dispersion is explained. It contains a two-stage-system: For first quick estimates the guideline contains the simple models MLuS and STREET. In case these models are not applicable or their results shows concentration levels close to the air quality standards, the more complex models PROKAS_V and MISKAM are recommended. PROKAS_V is a Gaussian plume model, MISKAM is a 3-dimensional microscale non hydrostatic flow model for built-up areas with an Eulerian dispersion model. The guideline comprises cases in rural areas without or with few adjacent buildings as well as urban areas with buildings near the roads. The contribution gives information about the models, typical results and some of the problems showing up presently.     

Hydrocarbon Utilization in Yeast Isolates Found to Grow in Association with Petroleum in a Polluted Ultisol of Midwestern Nigeria

The population counts of hydrocarbon-utilising yeasts weremonitored at six sampling stations in the Benin City municipalarea over a four-week period. Although the population countswere relatively constant in each locality, the highest countsoccurred in areas heavily polluted by domestic and industrialeffluents. A total of thirty-five hydrocarbon-degrading yeastswere isolated from soil at the sampling stations usingn-hexadecane as sole carbon source. The isolates were identifiedas belonging to the genera Candida (27 strains), Endomycopsis (4 strains). All the organisms grew on long-chainn-alkane, kerosene, diesel oil and crude oil but failed to growon short-chain n-alkane, aromatic and alicyclic hydrocarbons.Measurement of growth attributes of the isolates usingn-hexadecane, diesel oil and crude oil as substrates showed thatthe Candida species were better utilizers of hydrocarbonsubstrates relative to Endomycopsis and Schizosaccharomyces species.     

Hydrologic–Economic Model for Managing Irrigation Intensity in Irrigation Areas under Watertable and Soil Salinity Targets

This paper gives mathematical details and sample applications of SWAGMAN Farm (SWAGMAN, Salt Water and Groundwater Management), a farm-scale hydrologic economic model that integrates agronomic, climatic, irrigation, hydrogeological and economic aspects of irrigated agriculture. The model is capable of determining optimum mix of land use to keep watertable and soil salinity within acceptable limits while maximising the economic returns. Alternatively, the model can simulate water and salt balance and economics of a given cropping preference. Web-based and Geographic Information Systems versions of the model are available for integration with the environmental reporting systems of the irrigation areas.     

火焰原子吸收光谱法测定苏州开发区26种蔬菜中铜锌铁锰镍

用火焰原子吸收光谱法测定了苏州开发区26种蔬菜中的铜、锌、铁、锰和镍的含量。蔬菜样品用硝酸高氯酸混合酸进行消解。4次测定值的相对标准差<5%,加标回收率在92%～107%之间。26种蔬菜中铜、锌、铁、锰、镍的含量基本均在世贸组织规定的范围内。     

Using Multiple Taxonomic Groups to Index the Ecological Condition of Lakes

Biological indicators of communitiestypically reflect a common environmental signalreflecting the general condition of the ecosystem, as well asindividual signals by indicators differentiallysensitive to particular environmental conditions. Wedescribe here a method of integrating and interpretingsuch indicators from 19 New England lakes for fivetaxonomic groups (diatoms, benthos, zooplankton, fish,and birds). Our approach provides a systematicstandardized way to integrate multiple metrics fromdifferent taxonomic groups by addressing four elementscrucial to analyzing data from multiple indicators: covariate control, re-scaling of data, standardizing the sign of responses, and dimensional reduction. We evaluated the biologicalmetrics against individual environmental stressors andagainst multivariate physicochemical metricscharacterizing general anthropogenic stress among thelakes. The method detected a response to variationin the gross environmental condition of the lakes thatwas correlated across taxa and metrics. In addition,a differential response to near shore conditions wasdemonstrated for fish. The success of the approach inthis study lends support to its general application toecological monitoring involving complex data sets.     

Concentrations of Cadmium, Mercury and Selenium in Blood, Liver and Kidney of Common Eider Ducks from the Canadian Arctic

We determined concentrations of selected trace elements inlivers, kidneys and blood samples from common eiders (Somateria mollissima borealis) from the eastern Canadianarctic during 1997 and 1998. Concentrations of totalmercury and organic mercury were generally low in the liversof these birds (less than 6 and 4 g g^–1 dry wt,respectively). Selenium ranged between 11–47 g g^–1 inlivers. Renal cadmium concentrations were among the highestever published for this species (range: 47–281 g g^–1). The regressions of log-transformed concentrations ofthese trace elements in blood samples on those in liver orkidney were significant (all P-values < 0.05) andpositive. However, except for organic mercury (RM ² = 0.83), the co-efficients of determination were low tomoderate (range of R ²: 0.26–0.52), suggesting poorto moderate predictive capability. Furthermore, therelationships between total mercury in blood and liverchanged between 1997 and 1998, suggesting that it would notbe possible to predict consistently, concentrations ofmercury in blood from those in liver based on samples takenin one year. Blood samples can be used to determineconcentrations of these trace elements in common eiders (andprobably other sea duck species as well). The use of bloodsamples is especially warranted when it is undesirable tokill the animal such as when working with rare or endangeredsea duck species or when the objective is to relate traceelement exposure to annual survival rates. However, thepredictive equations developed here should not be used topredict expected concentrations in one type of tissue fromthose in the other.