PWD22能见度仪监测上海市水平能见度的试验研究

利用PWD22能见度仪监测数据,分析了上海市2008年—2009年能见度日变化规律和四季逐日变化特征,以及能见度和混合层高度(MLH,Mixed Layer Height)、空气污染指数(API)及气象要素(相对湿度、风速、温度)的相关性。结果表明,能见度一峰一谷日变化特征明显,峰值出现在14:00~16:00,谷值出现在6:00~8:00。能见度与MLH相关性显著,与温度最差。能见度和气溶胶光学厚度(AOT)线性拟合呈负相关关系,且夏季相关性最显著,冬季最差。     

青岛市采暖期PM2．5与大气能见度的关系

利用青岛市大气综合观测站的研究性监测数据,分析了2011年采暖期PM2.5和能见度的相关性,结果表明：①能见度在≤3km时,对应的PM2.5浓度超出0．250mg／m^3,属于严重污染;②PM2.5浓度对能见度的影响存在一临界区域,当PM2.5浓度低于该临界区时能见度会随PM2.5浓度减少迅速改善,临界值大致位于PM2.5浓度为0．100mg／m^3处;③相对湿度小于85％时,能见度与PM2.5浓度呈显著负相关。其中,相对湿度在60％-70％时,能见度与PM2.5浓度之间的相关性最好,PM2.5对能见度的影响最直接。     

宁波市秋冬季大气能见度特征及影响因素分析

针对宁波市大气能见度的观测研究表明,宁波市秋冬季大气能见度均值为11.6 km,霾日发生率为31.6%,霾日的能见度均值为6.6 km,且PM_(2.5)质量浓度在100~120μg/m3范围内的频率最高。能见度随着PM_(2.5)浓度增大呈指数下降,且相同的PM_(2.5)浓度情况下,相对湿度越大,能见度越低。能见度为10 km的临界点上,PM_(2.5)质量浓度值对应为67.5μg/m3。不同相对湿度时,能见度为10 km对应的PM_(2.5)质量浓度临界值不同。通过建立能见度回归方程发现,低相对湿度(RH≤30%)时,PM_(2.5)对能见度的影响权重最大;高相对湿度(RH60%)时,相对湿度的权重最大;RH低于60%时,RH的权重随着PM_(2.5)浓度的增加而增大;而RH高于60%时,RH的权重随着PM_(2.5)浓度的增加而减小。分析结果可为宁波市灰霾防治和采取合适的管控措施提高能见度提供一定参考。     

灰霾天气不同粒径的颗粒物污染特征分析

利用宁波市北仑区PM10、PM2.5和PM1的监测数据及与之对应的能见度监测结果,对影响灰霾天的颗粒物的污染特征进行了系统研究,结果表明,颗粒物粒径对灰霾天的形成和能见度的影响程度差异明显,且3种粒径的颗粒物质量浓度与能见度之间线性关系密切。     

南京北郊气溶胶散射特性观测研究

南京北郊是重工业区,空气污染严重。该文利用浊度仪对大气气溶胶散射系数进行了四季观测,研究了该区气溶胶散射系数、后向散射比、质量散射系数及散射系数与能见度的关系,结果表明,观测期间散射系数波动较大,平均值为344.84 Mm^-1,标准差为215.99 Mm^-1,散射系数季节差异明显,主要受气象条件和外界污染排放的影响;后向散射比平均值为0.139,春季变化剧烈,夏、秋、冬季在波动中缓慢上升,大气中细粒子污染严重且含量有增加的趋势;散射系数与PM_2.5质量浓度相关系数达到0.91,质量散射系数平均值为1.87m²/g;散射系数与能见度之间存在-0.66的相关性,两者呈负幂函数关系。     

1984—2015年太湖地区大气能见度变化遥感监测与评价

研究收集整理了1984—2015年太湖区域342幅Landsat系列卫星遥感影像,利用ENVI软件FLAASH模块计算获取了区域大气能见度均值,通过太湖周边苏州、无锡、常州3市地面自动站能见度监测值加以验证,并在此基础上对1984—2015年该地区大气能见度遥感监测结果进行了分析与评价。研究结果表明：太湖地区在20世纪80年代能见度水平相对较好,20世纪90年代后逐渐下滑,总体呈下降趋势。2015年遥感反演能见度均值为14.80 km,与1984年的21.46 km相比下降了31.05%,下降速率约为0.21 km/a。     

合肥市颗粒物和气象条件对大气能见度的影响研究

利用2019—2021年合肥市气象参数、颗粒物浓度、颗粒物化学组分、颗粒物散射系数、颗粒物粒径谱等的逐小时观测数据,分析了合肥市大气能见度变化趋势及其影响因素。结果表明,2019—2021年,合肥市能见度呈逐年上升的总体特征,并且在季节变化上呈现为夏高冬低,在日变化上呈现为午后最高、夜间最低。相关性分析结果显示,合肥市能见度与颗粒物浓度、相对湿度均呈显著负相关关系,且能见度与相对湿度的相关程度比与颗粒物浓度的相关程度高15.5%~219.2%。相对湿度是直接影响合肥市能见度的主要因素之一,而温度、风速对能见度的间接影响作用相对较小。能见度与颗粒物特性关系研究结果表明:能见度与水溶性离子的相关程度高于与碳质组分的相关程度;当能见度处于较低水平时,能见度与PM_2.5主要组分浓度的相关性明显减弱,相对湿度、超细颗粒物占比、水溶性离子含量和碳质组分含量等因素对能见度的影响逐渐凸显;在较高PM_2.5浓度环境条件下,颗粒物散射系数的显著变化是导致能见度降低的主要原因;小粒径颗粒物对合肥市大气能见度的影响程度相对较高,应优先大幅度降低PM_1.0浓度。     

建立空气质量综合评价指数的探讨

分析了空气污染指数(API)系统在评价空气污染水平中的不足,提出了在原API系统基础上进行指标拓展,增加能见度和PM2.5评价指标,建立空气质量综合评价指数（AQI）;分析了扬州市区PM2.5和能见度在雾霾日及正常日的百分位分布,确定了PM2.5和能见度分级值,并利用扬州市区环境空气质量监测数据进行了验证。     

2009年广州能见度变化规律及主要影响因素分析

通过对2009年的广州大气能见度和影响因素的数据资料统计,结合定性分析、相关性计算及各时间尺度中物理量的相互作用过程研究,得出能见度的变化规律和各因素的相关性特征。结果表明,2009年整体能见度水平略有提高;24h的降雨量、气温差值较大时,该日的能见度小时均值波动较大;风速、相对湿度与中尺度(24h)能见度的相关性较强;降雨量、气温对小尺度(1h、5min)能见度影响显著;相对湿度水平能制约风速对能见度的改善作用。灰霾现象等与能见度水平密切相关。     

基于Landsat 8卫星OLI影像遥感反演盐城市区域大气能见度状况

利用遥感软件ENVI 5.2的FLAASH大气校正模块,对盐城市2013—2014年共22景Landsat 8卫星OLI影像进行了区域大气能见度遥感反演,并与盐城市环境监测中心站的空气自动监测子站的PM10、PM2.5以及当地气象部门的能见度观测数据进行了对比。结果表明,OLI遥感影像可以对区域尺度大气能见度进行有效的观测,反演的区域性大气能见度水平与地面空气质量自动监测结果存在消长关系,与地面能见度数据有近70%的一致性。     

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.     

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.     

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.     

Impact of Pollution Caused by Uranium Production on Soil Macrofauna

Thirty years of mining and milling activities of the Priargunsky Mining-Chemical Production Company (South-Eastern Siberia, Russia) have resulted in an enrichment of uranium in adjacent steppe soils by a factor of up to 600. A number of attendant pollutants (thorium, arsenic and heavy metals) also have high concentrations in the soil. To estimate the effects of this pollution on soil-living macroinvertebrates, pitfall trapping and core sampling were applied. The element composition of four beetle species was analysed. Soil macroinvertebrates had 3–37 times lower abundance and biodiversity at the contaminated sites compared with the control. Ground beetle communities at the contaminated sites were reduced compared to the control site. The concentrations of uranium and arsenic in beetles collected at the contaminated sites were 2–41 and 2–26 times higher, respectively, than at the control site. There is strong evidence that the contamination caused by uranium production has severe negative biological effects on important groups of the soil food web.     

Eutrophication and Sedimentation Patterns in Complete Exploitation of Water Resources Scenarios: An Example from Northwestern Semi-arid Mexico

Water requirements to supply human needs lead water stakeholders to store more water during surplus periods to fulfil the demand during – not only – scarcity periods. At the reservoirs, mostly those in semi-arid regions, water level then fluctuates extremely between rises and downward during one single year. Besides of water management implications, changes on physical, chemical and biological dynamics of these drawdown and refilling are little known yet. This paper shows the results, throughout a year, on solids, nutrients (N and P), chlorophyll-a, and sedimentation changes on the dynamics, when the former policy was applied in a reservoir from the semi-arid Northwestern Mexico. Water level sinusoidal trend impinged changes on thermal stratification and mixing, modifying nutrient cycling and primary producer responses. According to nitrogen and phosphorus concentration as well as chlorophyll-a, reservoir was mesotrophic, becoming hypertrophic during drawdown. Nutrient concentrations were high (1.22 ± 0.70 and 0.14 ± 0.12 mg P l⁻¹), increasing phosphorus and lowering N:P significantly throughout the study period, although no intensive agricultural, no urban development, neither industrial activities take place in the watershed. This suggests nutrient recycling complex mechanisms, including nutrient release from the sediment–water interface as the main nutrient pathway when shallowness, at the same time as mineralization, increases. Outflows controlled nitrogen and phosphorus availability on the ecosystem while organic matter depended on river inflows. As on other subtropical aquatic ecosystems, nitrogen limited primary productivity (Spearman correlation R = 0.75) but chlorophyll-a seasonal pattern showed an irregular trend, prompting other no-nutrient related limitants. Shallowness induced a homogeneous temporal pattern on water quality. This observed temporal variability was mainly explained statistically by changes on solids (mineral and organic), chlorophyll-a and flows (62.3%). Annual sedimentation rates of total solids ranged from 11.73 to 16.29 kg m⁻² year⁻¹ with organic matter comprising around 30%. N:P ratio on sedimentation rates were as high as could be expected in a resuspension dominated ecosystem, and spatially inverse related with N:P ratio on bottom sediments. Distance from river inlet into the reservoir reveals a marked spatial heterogeneity on solid and nitrogen sedimentation, showing the system dependence on river inflows and supporting resuspension as the main phosphorus pathway. Accretion rates (2.19 ± 0.40 cm year⁻¹) were not related to hydrological variability but decreased with the distance to the river input. Total sediment accumulation (9,895 tons km⁻² year⁻¹) denotes siltation as other serious environmental problem in reservoirs but possibly not related with operational procedures.