西沙永兴岛黑碳浓度特征初探

2012年5月6—9日利用黑碳仪获得了西沙永兴岛小时黑碳浓度数据。结果显示,西沙永兴岛黑碳小时浓度值变化范围为0.1~2.9 μg/m³,平均浓度为0.6 μg/m³,80.5%的小时浓度数据集中在0.2~0.7 μg/m³;黑碳浓度与风速、降水密切相关,风速大于2.5 m/s有利于黑碳扩散,降水对黑碳冲刷作用明显;黑碳浓度与背景区域的瓦里关黑碳浓度相近,高于背景区域的南极中山站,明显低于国内的多个城市及郊区的黑碳浓度。     

沈阳臭氧污染时空分布特征及变化趋势

以沈阳2013—2015年臭氧(O_3)监测数据为基础,从地域差异及时间变化上分析了沈阳O_3浓度变化特征。结果表明:沈阳城市外围O_3浓度高于城市中心;O_3浓度变化具有明显季节特征,夏季O_3浓度最高,冬季最低;O_3浓度日变化呈单峰分布,谷值出现在06:00,峰值出现在14:00;O_3浓度出现明显"周末效应",周末白天O_3浓度高于工作日O_3浓度,夜间差异不大。     

沈阳地区臭氧污染日时空变化特征及天气分型研究

利用2013—2019年沈阳地区11个国控监测站近地层臭氧(O_3)浓度监测数据和地面气象观测资料,分析了沈阳地区O_3污染日的O_3浓度时空分布规律,并对造成O_3污染日的天气系统进行了主观分型。结果表明:自2013年以来,以O_3为首要污染物的天数逐年增加,2017年达到研究期内的最高值,但2018—2019年略有下降。O_3浓度的日变化趋势呈现明显的单峰形,O_3-1 h在10:00—20:00明显高于其他时间段,最大浓度值出现在15:00,而在01:00—07:00则相对较低。从季节变化上看,沈阳地区O_3污染主要发生在6—7月,两个月的O_3污染日之和占全年O_3总污染日的比例高达51%。从O_3浓度空间分布上看,沈阳地区三环外监测站测得的O_3浓度明显高于三环内监测站,高浓度区域主要集中在东部和东北部,城市中心存在明显的低浓度区,南部和北部差别不大,但也明显高于城市中心。造成沈阳地区O_3污染的主要天气类型有4种:暖脊型、均压场型、高空槽型和副热带高压型。其中:暖脊型出现的频次最高,占总样本的49.1%;副热带高压型出现的次数最少,占总样本的7.7%。     

连云港黑碳气溶胶污染特征研究

采用2016年大气多参数站监测数据,分析连云港市大气中ρ(黑碳气溶胶)的小时及月度变化规律,结果表明,观测期间,黑碳气溶胶与NO_2、CO、PM_(10)、PM_(2.5)显著相关,与风速、能见度等呈负相关;黑碳气溶胶年均值为2.10μg/m~3,日变化呈明显双峰型,峰值出现在08:00和21:00左右;从季节看,ρ(黑碳气溶胶)冬春季高、夏秋季低;在不利气象条件时,ρ(黑碳气溶胶)有所增高,通过模型分析化石燃料燃烧产生的黑碳占比增大,说明在不利气象条件时,化石燃料燃烧产生的黑碳是影响ρ(黑碳气溶胶)及ρ(颗粒物)上升的主要因素。     

贵阳市臭氧浓度变化及与气象因子的关联性

运用2013—2016年贵阳市环境空气自动监测站臭氧(O_3)的监测数据以及气象观测资料,分析该地区近地面O_3浓度的时空变化特征及与气象因子的关联性。结果表明,近年来贵阳市近地面O_3小时浓度均值有逐年升高趋势,增速为1. 1～5. 0μg/(m~3·a)。O_3浓度昼间变化呈明显单峰形分布,08:00左右出现最低值,15:00—16:00达到最大峰值,浓度高值主要分布在12:00—18:00。日照时数每增加1 h,则近地面O_3日最大8 h平均浓度增加8μg/m~3左右,日照时数大于8 h,则近地面O_3日最大8 h平均浓度超过100μg/m~3; O_3小时浓度与温度呈正相关(r=0. 724,α=0. 01),与相对湿度呈负相关(r=-0. 531,α=0. 01)。当日照时数大于8 h、温度超过25℃、相对湿度小于60%时,贵阳市近地面O_3容易出现高浓度值。     

2021年苏州黑碳气溶胶浓度特征及来源解析

于2020年12月1日—2021年11月30日利用7波段黑碳仪（AE-31）观测苏州地区黑碳（BC）浓度变化特征,并使用黑碳仪模型和后向轨迹模型分析BC排放来源和潜在源区。结果发现,苏州地区BC年平均质量浓度为（1.29±0.64）μg/m³,冬季BC质量浓度最高,为（1.61±0.89）μg/m³,秋季为（1.34±0.61）μg/m³,春季为（1.23±0.48）μg/m³,夏季最低,为（1.03±0.43）μg/m³。各季节工作日、非工作日BC质量浓度日变化均呈早晚双峰分布规律。BC质量浓度与风速、气温、降水量呈负相关,与相对湿度相关性并不显著。黑碳来源解析结果表明,相比于固体燃料（如煤和生物质燃烧）,液体燃料（如交通排放）对苏州BC质量浓度的贡献在各季节均占主要地位（74.2%～76.3%）,且夏季最高,冬季最低。同时,后向轨迹模拟和浓度轨迹权重分析的潜在源区结果显示,与本地污染相比,影响苏州地区BC的更多为输送型气团;各季节BC的潜在源区也稍有差异,主要以西南方向的影响为主。     

杭州市环境空气中黑碳质量浓度变化特征

采用2013年环境空气自动监测数据,分析杭州市空气中黑碳质量浓度的变化规律,并对变化特征的产生原因进行探讨。结果表明:黑碳测定年均值为4.10μg/m3,日变化有明显双峰结构,峰值出现在早7时和晚8时左右;从季节看,黑碳质量浓度冬季高(5.20μg/m3)、夏季低(3.00μg/m3);黑碳质量浓度与NO2、CO、PM10、PM2.5显著相关,与O3、风速、气温呈负相关,降水对黑碳的清除作用明显。     

宝鸡高新区黑碳气溶胶浓度特征及其影响因素研究

为研究宝鸡高新区黑碳(BC)气溶胶浓度的变化特征及其影响因素,利用2017年3月1日至2018年2月28日的BC气溶胶浓度、PM_(2.5)质量浓度以及风速风向数据,对该地区BC气溶胶质量浓度特征变化及其影响因子进行分析。结果表明,宝鸡高新区BC和PM_(2.5)质量浓度范围分别为0.35~6.18μg/m~3和8.01~192.20μg/m~3,平均值分别为(1.67±1.22)μg/m~3和(46.96±33.18)μg/m~3。BC气溶胶的背景质量浓度为(0.81±0.76)μg/m~3。BC与PM_(2.5)的相关系数为0.673,呈正相关。观测期间10—12月BC质量浓度较其他月份相对较高,其季节变化由大到小依次为冬季秋季春季夏季,这可能与采暖季用煤及气象条件不同有关。BC气溶胶的日变化有峰谷值,峰值出现在07:00—09:00和20:00—22:00,谷值出现在14:00—16:00。BC和PM_(2.5)质量浓度均随污染等级加重而增加。宝鸡高新区BC污染在西北风向下较为严重,且此时风速较小,BC质量浓度与风速的相关系数分别为-0.438,呈负相关,静风和非静风条件下BC平均质量浓度分别为2.50μg/m~3和1.53μg/m~3,表明静风条件下,污染物容易累积,导致BC质量浓度升高。     

成都市O3浓度的时间变化特征及相关因子分析

为深入认知成都市O_3浓度的时间变化规律及其影响因子,基于2013年1月1日—12月31日市区站点O_3、NO、NO_2、NO_x的逐时监测资料以及成都市气象站的气象数据逐时观测资料,据此对O3的季变化、日变化、"周末效应"、"节假日效应"进行了讨论,并对其浓度影响因子进行分析。结果表明:成都市O_3浓度季变化呈现明显夏高冬低的特征,浓度最大值出现在8月。O_3浓度日变化为单峰型,夏季峰值出现在15:00,冬季峰值出现在16:00。市区存在"周末效应",即周末O_3浓度总体比工作日高;"节假日效应"则表现出复杂多变性,受气象条件以及人为活动等多种随机因素的影响。O_3日平均浓度与NO、NO_2、NO_x、相对湿度呈明显负相关,与温度、风速呈明显正相关。     

北京市交通环境监测点大气污染特征分析

研究分析了2013—2017年北京市交通环境点位大气污染物浓度分布特征,结果发现:交通监测点NO、NO_2与PM_(2.5)浓度时间变化特征与城区总体状况基本一致,与交通环境密切相关的NO_2浓度采暖季高于非采暖季,重污染日期间交通监测点峰值浓度也明显偏高;周末交通监测点NO浓度在5:00—23:00低于工作日4.9%～32.1%,周末NO_2浓度在7:00—23:00低于工作日0.7%～7.4%,NO_x浓度周末偏低与车流量降低密切相关;重大活动期间空气质量减排措施实施后,北京市作为区域NO_2浓度高值区中心明显消失,PM_(2.5)浓度分布梯度减小,本地减排效果明显。     

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.