Visual Assessment of Foliar Injury Induced by Ozone on Indicator Tobacco Plants: A Data Quality Evaluation

A group of 50 inexperienced scorers were asked to estimate –using standard reference photos – foliar injury induced by the gas pollutant ozone on the supersensitive indicator planttobacco (Nicotiana tabacum L.) cv. Bel-W3. Theaverage accuracy level was 56.1% (95.9% when theclasses nearest to the reality were also consideredcorrect) and the average repeatability was 65.4%. Theextreme classes were easily scored. Central classesproved to be more difficult to be evaluated: this maydepend on the fact that two leaves may have similaractual total injured area, but substantially differentnumbers and spatial distribution of the lesions. Insome cases we observed a prevalence of overestimationerrors in the high classes and underestimation in thelow classes: this is in contradiction with theWeber-Fechner law. It is noteworthy the very shorttime required by operators to score, regardless of the results.     

Monitoring of Criteria Air Pollutants in Bursa, Turkey

The concentrations of criteria air pollutants such as CO, NO_x (NO + NO₂), SO₂ and PM were measured in the period of May 2001 and April 2003 in the city of Bursa, Turkey. The average concentrations for this period were 1115±1600 μg/m³, 29±50 μg/m³, 51±24 μg/m³, 79±65 μg/m³, 40±35 μg/m³, 98±220 μg/m³, for CO, NO, NO₂, NO_x, SO₂ and PM, respectively. Temporal changes in concentrations were analyzed using meteorological factors. Correlations among pollutant concentrations and meteorological parameters showed weak relations nearly in all data. Lower concentrations were observed in the summer months while higher concentrations were measured in the winter months. The increase in winter concentrations was probably due to residential heating. Pollutants were associated with each other in order to have information about their origin. NO_x/SO₂ ratio was also examined to bring out the source origin contributing on air pollution (i.e., traffic or stationary).     

上海市臭氧污染时空分布及影响因素

分析2006—2016年上海市的监测数据发现,臭氧(O_3)浓度存在逐年上升趋势,污染持续时间有所增加,但除水平风速有下降趋势外,其他相关气象因素的年际变化趋势并不显著。空间分析结果表明,上海市O_3超标主要集中在西南部郊区,但市区O_3超标潜势不容忽视。O_3污染高发季节的污染玫瑰图分析发现,上海市南部地区是影响上海市O_3污染的关键区域;对于NO_2减排的影响分析发现,尽管上海市O_3平均浓度总体处于上升趋势,但在NO_2下降幅度最为明显的内环市区和北部郊区,O_3上升幅度低于NO_2下降幅度较小的内外环区域和西部郊区,表明上海市的O_3污染控制仍需持续推进NOx的减排,并同步推进VOCs的减排。     

辛集市"十三五"期间空气质量特征分析

重点对河北省辛集市"十三五"期间整体空气质量变化情况以及影响辛集市优良天数的2个重要参数O₃和PM_2.5的污染规律进行了分析。结果表明,辛集市"十三五"期间空气质量改善明显,优良天数整体增加,污染天数整体减少。O₃浓度及其作为首要污染物出现的天数整体呈现上升趋势,对综合指数的贡献率逐年增加;O₃污染高发期主要集中在4—9月,高值区域分布差距较大,但市区污染持续突出。PM_2.5浓度逐年下降,以PM_2.5为首要污染物的天数逐年减少;PM_2.5浓度季节变化特征整体呈现"秋冬高、春夏低"的分布特点,空间分布呈"南北高、中间低"的污染特征。     

邯郸地区2017—2021年PM2.5和O3污染特征

利用实时监测数据分析2017—2021年邯郸市及周边区县PM_2.5和O₃污染特征。研究发现:2017—2021年各地区PM_2.5年均质量浓度持续降低,轻度及轻度以上污染逐渐减少;2017—2019年O₃污染加剧,2020年起O₃年均质量浓度逐年下降,污染天不断减少。PM_2.5和O₃-8 h分别在1月(平均浓度为127.3 μg/m³,平均超标22d)和6月(平均浓度为233.4 μg/m³,平均超标22 d)污染最严重。结合气象参数分析来看,PM_2.5与温度、风速和降水量呈显著负相关,与相对湿度呈显著正相关;O₃-8h与温度呈显著正相关,而与风速、湿度和降水量的相关性较弱。后向轨迹和潜在源分析表明:邯郸地区PM_2.5典型污染月受山西省中部地区污染传输影响最大,O₃典型污染月受河南省东部污染传输影响最大。     

山西省大气污染特征及对公众健康的空间影响

利用山西省11个地级市大气环境监测站的PM_2.5、PM₁₀和O₃浓度数据,分析了2015—2020年山西省PM_2.5、PM₁₀和O₃浓度时空变化特征,采用空间计量模型和岭回归方法,分析了空气污染对公众健康的空间影响。结果表明:PM_2.5和PM₁₀年均质量浓度总体下降,两者在2017年最高,2020年最低;O₃年均浓度总体增加。在季节尺度上,PM_2.5和PM₁₀质量浓度在冬季的12月和1月最高,夏季的8月最低;O₃浓度在6月最高。空间上,相较2015年,2020年山西省各地级市PM_2.5污染程度均有改善,其中长治改善效果最好;2020年山西各地级市PM₁₀污染兼有加重和减轻的情形,所有地级市PM_2.5和PM₁₀污染水平均超过国家二级污染浓度限值;2020年山西多数地级市O₃浓度升高。山西公众健康水平具有明显的空间离散特征,PM_2.5和PM₁₀浓度的局部空间自相关特征高度一致,呈现"南高北低"的格局,O₃浓度分布呈"南部高,中北部低"的格局。大气环境质量和经济发展水平均对医疗机构诊疗人数和健康体检人数的变化有正向影响,每万人卫生技术人员数量和公共财政支出比例对公众健康均有负向影响,其中经济发展水平和大气环境质量的影响最显著。山西省PM_2.5治理取得一定成效,但大部分城市PM_2.5和PM₁₀达标率较低,O₃浓度有持续升高的趋势,PM₁₀和O₃污染改善缓慢,深度减排仍面临挑战。PM_2.5和PM₁₀是危害山西公众健康的主要大气污染物,未来需要加强PM_2.5、PM₁₀和O₃的精细化管理及协同治理。     

2022年春季南京臭氧污染特征及成因分析

2022年春季,受新一轮新冠疫情影响,长三角各城市采取了一系列管控措施,使得大气污染物排放水平降低。对2022年春季(3—5月)南京及长三角地区的六项污染物尤其是臭氧(O₃)的变化特征进行了分析,从气象因素和O₃前体物方面,同时利用基于观测的模型(OBM)对南京O₃污染变化原因进行了研究,并分析了南京挥发性有机物(VOCs)的关键活性组分和来源。结果表明:2022年春季,南京PM_2.5、PM₁₀、NO₂和CO均值浓度均同比下降,但O₃日最大8 h滑动平均质量浓度(O₃-8 h)同比上升19.8%,O₃-8 h超标时间同比增加9 d;长三角区域O₃-8 h同比上升17.9%,O₃-8 h超标天数为2021年同期的2.5倍。南京O₃浓度上升的原因:一方面是由于不利的气象条件,另一方面是由于南京O₃生成处于VOCs控制区,但氮氧化物(NO_x)降幅大于VOCs降幅,同时结合O₃前体物削减方案的分析结果发现,VOCs和NO_x不当的削减比例会导致O₃浓度不降反升。南京O₃生成的关键VOC活性物种依次为乙醛、丙烯、间/对二甲苯、丙烯醛和乙烯;正定矩阵因子分解(PMF)解析结果显示,机动车尾气是南京城区VOCs的主要来源,其次为液化石油气/天然气使用和石油化工。     

基于转置EKMA曲线的湖南省臭氧生成敏感性分析

基于湖南省2015—2020年夏秋季的污染物及气象观测数据,分析了臭氧（O₃）污染的时空特征和生成敏感性。湖南省中部和北部的O₃污染较为严重,且主要发生在9月,午后O₃峰值常与早高峰的NO₂浓度有较高的相关性。采用转置EKMA曲线方法探究了O₃在NO₂维度和VOCs反应活性维度下的生成敏感性。在 NO₂维度下,NO₂控制区和NO₂-VOCs过渡区的NO₂质量浓度为7 ~ 13 μg/m³,NO₂-VOCs过渡区和VOCs控制区的NO₂质量浓度为15~17 μg/m³。在VOCs反应活性维度下,当NO₂质量浓度大于10 μg/m³时,VOCs反应活性越高,O₃浓度越高。在高VOCs反应活性（30 ℃或以上）时,NO₂浓度每降低1 μg/m³,各区域的O₃质量浓度能降低约8 ~ 9 μg/m³。结合NO₂ 和VOCs反应活性2个维度,得出湖南省午后O₃生成以 NO₂控制区和NO₂-VOCs 过渡区为主,在晴天干燥和高温条件下,减排NO₂可有效降低O₃浓度。转置EKMA曲线方法为缺少长期VOCs观测的区域提供了研究O₃生成敏感性的新思路。     

环境空气质量新标准对珠三角区域站空气质量评价的影响

利用粤港珠三角区域空气质量监控网中天湖、金果湾与万顷沙3个区域站2010年全年SO₂、NO₂、PM₁₀、O₃、PM_2.5与CO自动监测的数据,分析了实施环境空气质量新标准(GB 3095—2012)对这3个子站空气质量评价的影响。研究发现,若采用新标准,万顷沙的NO₂、PM₁₀和PM_2.5年均浓度将不同程度超标。这3个子站空气质量达标率下降7~28个百分点,空气污染指数从91%~99%下降至63%~91%;O₃的引入是导致空气质量达标率下降的最主要的原因;O₃将取代PM₁₀成为最主要的首要污染物,出现频率大于50%,且O₃(8 h)平均浓度的影响大于O₃ (1 h)浓度的影响。PM_2.5的纳入也是导致空气质量达标率下降的重要因素,其超标率为3%(金果湾)~16%(万顷沙)。NO₂标准的收严未对天湖与金果湾空气质量评价造成影响,但导致万顷沙NO₂的超标率从2%上升至10%,且NO₂作为首要污染物的比例达24%。     

Extreme Nitrogen Oxide and Ozone Concentrations in Athens Atmosphere in Relation to Meteorological Conditions

In the present study, we investigate the variation of NO _x (NO + NO₂) and O₃ concentrations and the relation between the extreme events (episodes) of NO _x and O₃ concentrations and the relevant meteorological conditions in the urban atmosphere of the Athens basin. Hourly data of NO, NO₂ and O₃ concentrations from 10 representative monitoring sites located in the Athens basin were used, covering the 10-year time period from 1994 to 2003. The results of our analysis show that the concentrations of air pollutants differ significantly from one monitoring site to another, due to the location and proximity of each station to the emission sources. For each site, there are also significant differences in NO _x and O₃ concentrations from day to day, as well as from month to month and/or from season to season. The annual and seasonal variations show higher NO values in winter and lower in summer. On the contrary, NO₂ and O₃ values are higher in summer (photochemical production of O₃) and lower in winter. These differences are attributed, to a large extent, to the prevailing synoptic and meteorological conditions, the most important between them being the wind direction and speed as well as the atmospheric pressure. Our analysis of the identified 179 extreme NO _x air pollution events shows that most of them took place under anticyclonic conditions, associated with calm or weak winds (speed <2.5 ms⁻¹) of mostly southern to southwestern directions, as well as with low air temperatures and intense stable surface atmospheric conditions. There exists a significant decreasing tendency in NO _x air pollution episodic events over the 10-year study period, resulting in very few to none events in the period from 2000 to 2003. As far as it concerns the extreme O₃ concentrations, 34 air pollution events were identified, occurring under high air temperatures, variable weak winds and intense solar irradiation. The trends of O₃ concentrations are stronger in suburban sites than in urban ones.     

Monitoring of Particle Mass and Number in Urban Air

Measurements of aerosol particles in the air of an urban area in the UK have been made. Ambient air was sampled and the particulates measured after passing through a size selective PM₁₀ inlet. Particle mass was measured using a Tapered Element Oscillating Microbalance (TEOM). Particle number and size distributions were obtained using an Electrical Aerosol Analyser (EAA) and an Aerodynamic Particle Sizer (APS). Measurements were also made of local meteorological parameters. Fine particle number concentrations were found to show better temporal agreement, including diurnal variation, with particle mass concentrations than the coarser particle number concentrations.     

Outdoor-indoor air quality in Riyadh: SO2, NH3, and HCHO

A funded research project was conducted during the period July1992 through November 1994. The project was designed to evaluateindoor and ambient air quality in and around buildings of different types and uses in Riyadh, the capital of Saudi Arabia.Thirty intercity buildings and two outercity (background) siteswere carefully selected and monitored for air quality. Ten airpollutants, together with relevant meteorological parameters, were monitored indoor and outdoor at each site continuously andsimultaneously for a period of two weeks covering summer and winter seasons.This article discusses the results obtained for sulfur dioxide (SO₂), ammonia (NH₃) and formaldehyde (HCHO). Results of this investigation revealed that most sites had on the averageexceeded the recommended standards for SO₂ and NH₃ bothindoor and outdoor, with indoor levels being worse than outdoorduring winter time. Several sites also showed high levels of HCHO, with outdoor levels being consistently higher than indoor.Statistical and frequency analyses were performed on the collected data, showing seasonal and sector by sector variability, and outdoor-indoor correlations.     

2016—2019年汾渭平原城市空气质量状况分析

基于2016—2019年全国城市环境空气质量国控监测点位自动监测数据,分析了汾渭平原城市空气质量状况。结果表明：2019年,汾渭平原优良天数比例为61.7%,略高于"2+26"城市,明显低于全国及其他区域,空气污染较重。2016—2019年,汾渭平原超标天数中PM_2.5、PM₁₀、O₃作为首要污染物的占比较高,PM_2.5、PM₁₀仍是影响汾渭平原空气质量的最主要污染物,O₃和NO₂的影响逐年升高。汾渭平原PM_2.5浓度呈夏季低、秋冬季高的特点,2019年与2016—2018年PM_2.5均值比较,1、2、4月分别偏高7.5%、36.7%、6.8%,其他月份均偏低,表明1、2、4月空气质量总体恶化,其他月份有所改善。汾渭平原O₃浓度呈夏季高、秋冬季低的特点,O₃浓度总体呈升高趋势,年平均升高10.3 μg/m³,临汾市年平均升幅最显著（26.7 μg/m³）,不同百分位O₃浓度均呈升高趋势,且高百分位浓度升幅明显高于低百分位浓度,年平均升幅最高出现在第90百分位浓度。2016—2019年,O₃单项污染物超标导致优良天数比例损失分别为5.4个百分点、13.0个百分点、11.1个百分点和14.4个百分点,总体呈上升趋势,表明O₃超标对空气质量影响越来越显著。煤炭消耗量、生铁产量、粗钢产量的大幅升高对空气质量有一定影响,建议加大对相关企业污染物的排放量检查,确保超低排放或采取可行的清洁能源替代。温度与O₃浓度呈正相关,2017—2019年,温度大于25 ℃的天数中94.2%出现在6—8月,O₃-8h超标天数占全部超标天数的81.4%,因此应加强温度较高月份的O₃管控。     

关于“十四五”生态环境监测支撑能力提升的思路与目标

生态环境监测是推进国家生态环境治理体系和治理能力现代化的重要支撑。党中央、国务院高度重视监测事业发展,将生态环境监测纳入生态文明改革的大局统筹推进。"十四五"时期,生态文明改革持续深入,生态环境治理将向精准治污、科学治污、依法治污转变,生态环境监测面临着全新的压力与挑战。因此,笔者以习近平生态文明思想为指导,按照"面向发展、服务公众、智慧监测、精准支撑"的原则,针对大气、地表水、土壤、地下水、生态等重点领域,提出了"十四五"时期生态环境监测的重点目标任务,为生态文明和美丽中国建设提供技术支撑。     

Comparison of ozone levels between working days and weekends in Athens,Greece

Athens has a major problem of ozone air pollution due to its climate which is dominated by hot and dry summers with intensesunshine. As a result there is a high violation of the air quality limits of ozone. By comparing ozone air pollution betweenweekdays and weekends it is possible to estimate the effect of the reduction of primary pollutants causing the formation ofozone on the levels of this pollutant. Thus it was estimated thatwhile during the weekends the concentrations of the ozone precursors (nitrogen oxides and volatile organic compounds) werereduced by the order of 10–20%, the effect on ozone levels was lower.     

“Ox增减量”O3人工订正预报方法与应用

为满足环境管理部门"O₃污染过程不漏、AQI类别准确和AQI范围预报准确"的要求,基于大气箱式模型和相似案例分析,引入O_x指标原创性提出"O_x增减量"O₃人工订正预报方法。介绍了该方法的预报思路、预报要点和步骤、历史相似案例库构建与基于大气条件预报的判别分析、方法普适性和局限性等,以期为提高区域、城市O₃业务预报准确率提供技术参考。以东部沿海城市青岛市为研究案例,结果显示,2020年6—9月24 h人工订正AQI类别预报、AQI范围预报准确率分别为91%和68%,比同期业务化运行的WRF-Chem数值模式预报准确率分别提高19%和25%,应用该预报方法可有效提高O₃污染过程预报准确率。     

宜都市PM2.5与O3季节性分布特征及潜在源区分析

为了解宜都市PM_2.5与O₃的污染特征及潜在来源,利用宜都市2020年3月至2022年2月在线监测数据及气象数据,对宜都市PM_2.5与O₃质量浓度变化特征、气象影响因素及潜在源区进行了分析,结果表明:宜都市PM_2.5质量浓度冬高夏低,日变化呈双峰特征,O₃质量浓度夏高冬低,日变化呈单峰特征。高湿、静稳的气象条件以及较强偏北风作用下的区域污染传输对PM_2.5污染有重要影响,高温以及中湿度对O₃污染过程有重要作用。春、夏、秋季偏南方向气流轨迹占主导,且携带较高的污染物浓度,冬季来自湖北东北及西南方向的气流占比较高且携带的PM_2.5浓度较高;宜都市PM_2.5、O₃的潜在源区具有季节性差异,总体来看,主要分布在河南南部、湖北东部及湖南的北部区域。     

“十一五”时期乌鲁木齐市大气污染特征及影响因素分析

为全面了解"十一五"时期(2006—2010年)乌鲁木齐市大气污染状况,评估污染源治理及气象条件对空气质量变化的影响,利用2001年1月—2010年12月主要大气污染物浓度数据和同期地面气象资料,总结"十一五"时期乌鲁木齐市大气污染变化特征,重点分析其变化原因。结果表明:"十一五"时期PM10和SO2年均浓度分别比"十五"下降1.7%和10.3%,采暖季降幅最明显,分别达到2.2%和21.9%;而NO2年均浓度比"十五"升高8.9%,非采暖季增幅最大,为11.7%。2006—2010年PM10、SO2年均浓度整体呈下降趋势,NO2浓度有升高趋势。5年中非采暖季各污染物浓度均达标,采暖季PM10和SO2超标倍数逐年减小,煤烟型污染特征仍然典型。污染源管控(特别是减排工程实施)是"十一五"时期SO2和PM10浓度下降的重要原因,气象条件作用相对有限。NO2浓度升高主要与机动车保有量逐年增加和氮氧化物治理启动滞后有关。     

江苏如东沿海经济开发区夏季O3污染特征及来源分析

为探究如东沿海经济开发区夏季大气中的O₃污染成因,基于2022年6月园区大气超级站的监测数据,较为全面地分析了O₃污染来源、水平及二次生成潜势等。结果表明:2022年6月园区O₃超标天数占比为34.5%,共计10 d,污染严重程度为2018—2022年同期最高水平(151 μg/m³);分析4个污染过程发现,高温低湿、静稳天气易诱发O₃污染事件,结合污染天气象条件发现,当温度＞25℃且相对湿度＜ 75%时极易发生O₃污染;污染天VOCs组分贡献率主要受芳香烃、烯烃及烷烃影响,其中邻二甲苯、甲苯、间-对二甲苯是O₃管控的关键活性物种;后向轨迹聚类分析显示,园区O₃污染主要受到上海、江西和苏南本地气团输送的影响,主导轨迹出现概率分别为30%、27%和24%,其余小部分时段可能受到来自中国北部和东部的下沉气流影响。为科学管控园区夏季O₃污染,应加强监测并协同管控本地关键VOCs物种。     

台州市区PM2.5和O3污染特征及相互作用关系

基于2016—2020年台州市区大气污染物监测数据及气象观测资料,分析了台州市区PM_2.5和O₃的污染特征及受气象因素影响情况,并探究了不同季节下的PM_2.5浓度和O₃浓度的相关性及相互作用关系。2016—2020年,台州市区PM_2.5年均浓度和超标天数呈显著下降趋势,O₃-8 h年均浓度和超标天数总体呈上升趋势。PM_2.5浓度在冬季最高,且易发生超标;O₃浓度在春、夏、秋季均较高,且均会发生超标。通过相关性分析可知：PM_2.5浓度与气温、相对湿度、风速、降水量呈负相关,与大气压呈正相关;O₃浓度与气温、风速呈正相关,与相对湿度、降水量呈负相关。不同季节下的PM_2.5浓度与O₃浓度均呈正相关,两者存在协同增长。在春、夏、秋季,二次PM_2.5在总PM_2.5中的占比随着O₃