长江三角洲地区南京特大城市居民点PM2.5和PM10的环境水平和时间变化.pdf

长江三角洲地区南京特大城市居民点PM2.5和PM10的环境水平和时间变化【中文5120字】

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长江三角洲地区南京特大城市居民点PM2.5和PM10的环境水平和时间变化【中文5120字】,长江,三角洲地区,南京,特大城市,居民点,pm2,以及,pm10,环境,水平,时间,变化,中文
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【中文5120字】环境科学与健康杂志,A部分有毒/有害物质和环境工程ISSN10934529(打印)15324117(在线)期刊主页HTTP/WWWTANDFONLINECOM/LOI/LESA20长江三角洲地区南京特大城市居民点PM25和PM10的环境水平和时间变化GUOFSHEN,SIYYUAN,YUNXIE,SIJXIA,LILI,YUKYAO,YUEZQIAO,JIEZHANG,QIUYZHAO,AIJDING,BINLIHAISWU引用本文GUOFSHEN,SIYYUAN,YUNXIE,SIJXIA,LILI,YUKYAO,YUEZQIAO,JIEZHANG,QIUYZHAO,AIJDING,BINLIHAISWU2014长江三角洲地区南京特大城市住宅区PM25和PM10的环境水平和时间变化,环境科学与医学杂志,A部分,492,171178,DOI101080/109345292013838851这篇文章的链接HTTPS/DOIORG/101080/1093452920138388511南京大学大气科学学院气候与全球变化研究所,南京2江苏省环境科学研究院大气科学研究所,南京,中国包括长江三角洲在内的中国东部地区的空气质量日益恶化,引起公众越来越多的关注。在这项研究中,我们测量了南京特大城市四个不同时间的环境PM10和PM25。24小时平均PM25和PM10质量浓度分别为00330234和00420328。PM10和PM25的日均浓度分别为29(2732,95可信区间)3/MG和42(3846)倍世界卫生组织空气质量准则,PM25为0025,PM10为0050,分别表明该市空气污染严重。没有明显的周3/3/MG末效应。冬季PM10污染最严重,冬季和夏季PM25负荷较高。PM25与PM10显着相关,PM10中PM25平均质量分数约为725。这个分数在不同采样期间有所不同,其中春季PM25分数最低,而其他三个季节则略有不同。关键词颗粒物,时间变化,周末效应,长江西部地区。引言由于对空气质量,人类健康和地方/区域气候变化的重大影响,环境颗粒物(PM)污染在世界范围内受到越来越多的关注16。一般认为高水平的颗粒物(PM)污染负责增加由于PM(尤其是PM25(直径小于25M的PM)的光消光(吸收和散射)导致大气能见度降低,所以发生雾度79。据估计,暴露于2010年,环境PM污染造成310万人死亡,全球DALY(残疾调整生命年)占31。10在全球范围内,环境PM污染是所有调查因素中第九高的风险因素,是东亚地区第四高的风险因素,也是唯一最大的环境风险因素10。实验测量和模型模拟研究已经确定了中国严重的空气污染,特别是在东部地区。1113据估计,中国大约三千五百到四十万人的早亡是由于环境空气污染和经济负担早期死亡率和发病率保守估计在2003年约为1570亿元人民币(占GDP的116),而在愿意支付估计的情况下可能高达5200亿人民币14,15包括上海和江浙两省在内的长江三角洲地区,是中国发展最为迅速,发展最快的城市化地区之一。据报道,该地区存在严重的空气污染问题。1619该地区报告了主要空气污染物,如微粒物质,黑碳和多环芳香烃相对较高的排放密度2023近三十年来,长三角区域的空气质量日益恶化,大气能见度明显下降7,17,长三角地区被确定为近期关节规划的重点预防和控制中国的大气污染。南京是江苏省省会,地处长三角西部,面积约6587平方公里,人口约810万。作为一个高度工业化和城市化的城市,南京遭受严重的大气问题。据报道,2004年南京的平均能见度只有88公里,日平均能见度10公里的日子全年约58。25有限的研究集中在这个城市的空气污染物,如PM,重金属和有毒有机物。2630迫切需要更多的研究,尤其是那些关注空气污染及其来源的研究,以支持决策者的环保决策。本研究的主要目的是对环境PM污染水平,特别是城市PM25的优良污染,PM质量分数和季节变化等基本认识。材料和方法抽样地点2011年11月和2012年3月,6月和8月,使用石英纤维过滤器(47MM,MILLIPORE)同时采集环境PM25和PM10样品24H。活性采样器(167L/MIN,武汉天鸿仪器,中国)被设置在附近一所大学住宅区的七层建筑的顶部屋顶上。采样点位于闹市区的下风向,是该市空气污染动态特征的代表性场所。16PM测量和质量控制过滤器在500预烘4小时,在使用前储存在干燥器中24小时。取样后,将装有颗粒的过滤器在干燥器中再处理24小时以达到平衡。在采样前后,使用高精度数字天平(XP105DR,METTLERTOLEDO,GREIFENSEE,瑞士)重量称重过滤器。根据质量差异和总采样量计算PM质量浓度。采样量为24048M3,平衡灵敏度为001MG,检测限为042G/M3。测量的不确定性来源于采样过程中的误差(即本研究中未考虑挥发性有机化合物的吸收)和体重测量。还进行了现场空白,这里报告的结果是空白的。数据分析NOAAHYSPLIT(混合单粒子拉格朗日积分轨迹)模型被用来计算空气质量轨迹31,以调查潜在的污染源和空降物质的长期运输。计算了来自采样点的72小时后向轨迹32。用SPSS(CHICAGO,IL,USA)进行数据分析,显着性水平为005。结果与讨论PM质量浓度图1显示了整个采样周期的日均PM25和PM10质量浓度。直线表示“中华人民共和国国家环境空气质量标准”(二级标准为环境空气功能区0075,环境空气功能区PM100150)和世界卫生组织(WHO)指南3/MG3/MG(0025PM25和0050PM10)。日常PM负荷有很大的变化。3/3/日均PM25和PM10浓度分别为00330234和00420328。3/3/MG总PM25和PM10平均值分别为0106和0146。本次研究的PM10浓G度日平均值为0150,为097倍(95置信区间为08911),PM253/G浓度为标准值的14(1315)倍。与世卫组织下午24小时的指导原则相比,PM污染严重得多。平均而言,日均PM10浓度约为世界卫生组织标准的29倍(2732)倍,而细小的PM25则是标准的42倍(3846倍)。图1南京市采样期24小时平均PM10(蓝色)和PM25(红色)质量浓度。国家标准和世界卫生组织的准则值也分别显示为不间断和虚线(颜色数字可在线获取)。总采样天数的40和74分别有24小时平均PM10和PM25浓度高于中国国家标准。与世界卫生组织标准相比,日均PM25和PM10浓度均超标,说明PM污染严重,城市大气污染对健康造成不利影响。本研究中发现的PM10水平远远高于全国平均水平008335。据国家3/MG统计,近10年来南京的年平均PM10浓度与北京,天津,上海等大部分主要城市相似,但高于南方的广州,海口和南宁中国。3620012004年北京市PM25年平均浓度为009601074,与目前研究的平均值0106相3/MG3/当。2003年,在全国14个城市(不包括南京)进行了一次野外活动,以同时测量环境PM25和碳含量37。与其他国内城市相比,南京冬季PM25浓度与北方平原和其他长三角地区如北京(01260066),天津(01790088)相当3/G(01510095),杭州(01680055),西北地区和重庆M3/MG(03120114)均低于西安(03750144)在中国西南地区。夏季,南京PM25低于北京(01170048),天津3/(01030028),西安(01310059)和重庆011600383/G3/),与杭州市(00910041)相当,但高于上海其他主要城市3/MG3/MG(00520019),广州(00490009MG/M3)M3),香港3/(00400014)和厦门(00250016)。M3总的来说,中国的空气污染严重,特别是与美国和欧洲地区的环境空气污染水平相比较13,3839。这些空气污染水平的差异城市被认为与当地较高的排放和区域远程运输的影响有关。未来,预计更多监测数据和PM来源信息的可用性将更好地理解城市之间和城市之间的动态变化,从而促进有效的污染控制策略。据报道,该地区大部分城市的PM10水平在2005年至2009年之间有下降的趋势,在南京,这5年PM10的年均浓度介于010和012MG/M3之间40,但本研究中的年平均PM10水平约为0146MG/M3,高于此前报道的数据。这种差异可能部分地由不同的采样点和测量方法来解释。ZHAO等人的研究40根据当地环境保护局报告的空气污染指数(API)计算PM10,而采用石英纤维过滤器对PM10进行采样和称重。API是一个无量纲指标,用来描述中国的空气质量。与空气质量指数相似,但只考虑五种污染物,即二氧化硫,二氧化氮,一氧化碳,臭氧和PM10。每种污染物都是单独测量的,用于根据每个空气质量分级标准的分级限值之间的测量浓度的线性插值来计算亚污染指数。最终的API是最高的污染指数。用于测量API的方法可以在QU等人41和环境保护部网站上找到42。此外,本研究仅包括一个抽样点,而城市报告的API通常基于多个地点的监测数据。这个采样点位于城市发展最快的地区之一,所以我们在本研究中发现的污染水平远远高于全市的平均水平,这并不奇怪。由于政府努力减少污染,如消除小火电厂,管理重污染行业,替代天然气替代煤炭和控制移动源,过去几年PM10的环境水平一直在下降。40,43然而,由于缺乏足够的代表性数据,很难知道环境PM25是否也有下降的趋势。除了地方排放外,运输和化学转化是影响空气质量的其他重要因素,这是该地区一个明显的现象。据报道,南方城市的空气污染物在夏季强烈辐射条件下通过形成二次污染影响顺风城市,而北方地区污染物的远距离输送在冬季更为明显。图2不同采样月份24小时平均PM10和PM25质量浓度。显示的数据是平均值,中位数,最小值,最大值和四分位数(25和75),其中有统计学意义的数值(P005)用星号标出(颜色数字在线)。计算变异系数(COV),其被定义为标准偏差除以平均值,以表征一个月内的时间变化。在不同的月份,PM25的COV值为2337,PM10的COV值为2533。影响次生地层,干湿沉降和区域远距离输运的许多因素,如当地初级排放,温度和风,都被认为会影响日变化。这些因素通常通过复杂的物理化学机制同时影响环境PM污染水平。根据大量更多的监测数据以及环境模型的潜在使用情况,研究时间变化及其可能的解释是非常有意义的。方差分析结果表明,PM25和PM10在这四个时期的差异有统计学意义(P005)。根据多项比较试验,我们发现11月份和6月份的冬季和夏季PM25负荷分别显着高于3月和8月。然而,与其他三个时期相比,PM10仅在冬季明显更高(图2)。冬季较严重的PM25和PM10的严重污染水平与固体燃料燃烧的主要排放物增加和污染物扩散的不利气象条件相结合25,45,46。在夏季(6月在本研究中),PM10浓度与3月份和8月份水平相当,而PM25浓度明显偏高。这可能部分地解释了夏季PM25次生形成的增强。37,4748来源的确定有助于解释在本研究中观察到的现象。周末效应具有广泛的意义,因为它可以提供有价值的信息,有助于评估环境模型,分析污染的原因,制定有效的污染控制策略49,50。(NO),二氧化氮(NO2)和一氧化碳(CO),周末臭氧水平可能较高,这可以解释为挥发性有机化合物(VOC)有限的臭氧层形成,臭氧排放量较高以及前体在星期五和星期六晚上,在排放时间和/或周末VOCS反应性增加50,51周末和工作日之间的污染物浓度的差异可能是污染物,位置和时间,49,5254例如,一些城市的城市周末和工作日平均PM25浓度差异不大。52,53,55在新德里,甚至发现在2002年,周末的PM10浓度高于平日54。表1列出了工作日和周末日的平均PM25和PM10浓度。工作日和周末日之间的差异没有统计学意义,这表明周围PM水平没有明显的“周末效应”南京在这个研究期间。据报道,南京的工作日和周末日平均能见度分别为88和89公里,这也表明没有显着的周末效应25。当地资源和长距离运输的变化可能导致周末和工作日期间环境PM浓度变化4957如果人们在周末呆在家里,较低的活动将会减少主要污染物的排放5258。然而,在许多城市情况并非总是如此53,56,59。PM10和PM25浓度差异不显着,PM25和PM10比值在周末(073008)和平日(069010)也是可比的。研究点PM的主要来源在整个采样周期和周末之间都没有很大的变化。不幸的是,本研究中,我们没有关于南京PM25和PM10的来源信息,这阻碍了在这方面进一步讨论周末效应。希望能够获得更多关于PM化学成分,主要来源以及气象条件影响的信息,从而更好地表征PM周末效应。使用非参数KOLMOGOROVSMIRNOV检验测试工作日和周末之间的差异,并列出统计P值。PM25质量分数图3显示了PM25和PM10之间的关系。显示出显着的正相关(P005),表明环境PM25和PM10可能来自同一来源或受类似因素影响。在采样期间,PM25一般占PM10的725左右。目前的中国国家标准PM25值是PM10的一半。因此,当PM25浓度超标时的日数通常高于PM10违反标准的日数(本研究中PM25和PM10分别为736和403)。5月6月8月11月总计PM25,MG/M3工作日0087003301040041009100340137003701040040周末09303501110034007100170175006501110054P0895P0514P0334P0125P0594工作日0132005201430055011700360179004801420052周末0156003101520046009800210239009101610069P0508P0961P0418P0125P0594四个采样月份的PM25质量分数不同。在3月份(春季),PM25仅占PM10的643,而其他月份PM25的比例为730774,没有显着差异。3月份PM25质量分数明显降低(P005),这与本年度西北地区的沙尘运移有关35,40。后向轨迹的结果也表明,3月份西部地区大部分空气来自其他采样周期的空气轨迹,如图4所示。图3不同采样期间PM10和PM25浓度之间的关系(颜色图在线提供)为了更好地了解严重的空气质量恶化的原因,促进城市有效的控制策略的制定,确定PM25和PM10的来源是非常重要的。这将需要分析PM的化学组成,如碳质碳组分,水溶性离子,元素和有机示踪剂,这些可用于PM源解析。分析气象条件对环境空气污染的影响也是有用的。未来,PM和其成分以及气态空气污染物的同时在线测量将是优选的。图4不同采样周期内采样点的后向轨迹显示了四个群集的手段(颜色图在线提供)。结论南京24小时平均PM质量浓度PM25为00330234,PM10为00423/MG0328。该市发现了严重的空气污染,日均PM10和PM25浓度分别约3/MG为世界卫生组织空气质量指南限值的29和42倍。没有明显的周末效应被发现。PM25和PM10水平在不同时期有明显的时间变化。在冬季(11月)测得的PM10浓度最高,冬季(11月)和夏季(6月)PM25浓度较高。平均而言,PM25占总PM10质量的725,而PM25质量分数明显偏低。致谢本研究得到中国博士后科学基金(2013M531322),国家自然科学基金(41301554)和江苏省自然科学基金(BK20131031)的资助。我们感谢匿名审稿人宝贵的意见。JOURNALOFENVIRONMENTALSCIENCEANDHEALTH,PARTATOXIC/HAZARDOUSSUBSTANCESANDENVIRONMENTALENGINEERINGISSN10934529PRINT15324117ONLINEJOURNALHOMEPAGEHTTP/WWWTANDFONLINECOM/LOI/LESA20AMBIENTLEVELSANDTEMPORALVARIATIONSOFPM25ANDPM10ATARESIDENTIALSITEINTHEMEGACITY,NANJING,INTHEWESTERNYANGTZERIVERDELTA,CHINAGUOFSHEN,SIYYUAN,YUNXIE,SIJXIA,LILI,YUKYAO,YUEZQIAO,JIEZHANG,QIUYZHAO,AIJDING,BINLI15324117ONLINEDOI101080/109345292013838851AMBIENTLEVELSANDTEMPORALVARIATIONSOFPM25ANDPM10ATARESIDENTIALSITEINTHEMEGACITY,NANJING,INTHEWESTERNYANGTZERIVERDELTA,CHINAGUOFSHEN1,2,SIYYUAN2,YUNXIE1,SIJXIA2,LILI2,YUKYAO2,YUEZQIAO2,JIEZHANG2,QIUYZHAO2,AIJDING1,BINLI2ANDHAISWU21INSTITUTEFORCLIMATEANDGLOBALCHANGERESEARCH,SCHOOLOFATMOSPHERICSCIENCES,NANJINGUNIVERSITY,NANJING,CHINA2INSTITUTEOFATMOSPHERICSCIENCES,JIANGSUPROVINCIALACADEMYOFENVIRONMENTALSCIENCES,NANJING,CHINATHEDETERIORATINGAIRQUALITYINEASTERNCHINAINCLUDINGTHEYANGTZERIVERDELTAISATTRACTINGGROWINGPUBLICCONCERNINTHISSTUDY,WEMEASUREDTHEAMBIENTPM10ANDFINEPM25INTHEMEGACITY,NANJINGATFOURDIFFERENTTIMESTHE24HAVERAGEPM25ANDPM10MASSCONCENTRATIONSWERE00330234AND00420328MG/M3,RESPECTIVELYTHEDAILYPM10ANDPM25CONCENTRATIONSWERE292732,AT95CONFIDENCEINTERVALAND423846TIMESTHEWHOAIRQUALITYGUIDELINESOF0025MG/M3FORPM25AND0050MG/M3FORPM10,RESPECTIVELY,WHICHINDICATEDSERIOUSAIRPOLLUTIONINTHECITYTHEREWASNOOBVIOUSWEEKENDEFFECTTHEHIGHESTPM10POLLUTIONOCCURREDINTHEWINTERTIME,WITHHIGHERPM25LOADINGSINTHEWINTERANDSUMMERPM25WASCORRELATEDSIGNIFICANTLYWITHPM10ANDTHEAVERAGEMASSFRACTIONOFPM25INPM10WASABOUT725THISFRACTIONVARIEDDURINGDIFFERENTSAMPLINGPERIODS,WITHTHELOWESTPM25FRACTIONINTHESPRINGBUTMINORDIFFERENCESAMONGTHEOTHERTHREESEASONSKEYWORDSPARTICULATEMATTER,TEMPORALVARIATION,WEEKENDEFFECT,WESTERNYRDREGIONINTRODUCTIONAMBIENTPARTICULATEMATTERPMPOLLUTIONISAGROWINGPUBLICCONCERNWORLDWIDEBECAUSEOFTHESIGNIFICANTIMPACTSONAIRQUALITY,HUMANHEALTH,ANDLOCAL/REGIONALCLIMATECHANGE16HIGHLEVELPMLOADINGSAREGENERALLYTHOUGHTTOBERESPONSIBLEFORTHEINCREASEDOCCURRENCEOFHAZEBECAUSETHEATMOSPHERICVISIBILITYCOULDBEREDUCEDDUETOLIGHTEXTINCTIONABSORPTIONANDSCATTERINGBYPM,ESPECIALLYTHEFINEPM25PMWITHDIAMETERLESSTHAN25M79ITHASBEENESTIMATEDTHATEXPOSURETOAMBIENTPMPOLLUTIONACCOUNTEDFOR31MILLIONDEATHSAND31OFGLOBALDALYSDISABILITYADJUSTEDLIFEYEARSDURING201010GLOBALLY,AMBIENTPMPOLLUTIONWASTHENINTHHIGHESTRISKFACTORAMONGALLOFTHEFACTORSINVESTIGATED,WHILEITWASTHEFOURTHHIGHESTRISKFACTORINEASTASIAANDTHESINGLELARGESTENVIRONMENTALRISKFACTOR10EXPERIMENTALMEASUREMENTSANDMODELSIMULATIONSTUDIESHAVEIDENTIFIEDSEVEREAIRPOLLUTIONINCHINA,ESPECIALLYINTHEEASTERNAREA1113ITISESTIMATEDTHATABOUT350400THOUSANDSPREMATUREDEATHSWEREATTRIBUTABLETOAMBIENTAIRPOLLUTIONINCHINAANDTHEECONOMICBURDENOFPREMATUREMORTALITYANDMORBIDITYWASCONSERVATIVELYESTIMATEDATABOUT157BILLIONRMB116OFTHEGDPIN2003,ANDMAYBEASHIGHAS520BILLIONRMBUSINGTHEWILLINGTOPAYESTIMATION14,15THEYANGTZERIVERDELTAYRD,WHICHINCLUDESTHECITYOFSHANGHAIANDTHEPROVINCESOFJIANGSUANDZHEJIANG,ISONEOFTHEMOSTDEVELOPEDANDFASTESTGROWINGURBANIZEDREGIONSINCHINAASERIOUSAIRPOLLUTIONPROBLEMHASBEENDOCUMENTEDINTHEREGION1619RELATIVELYHIGHEMISSIONDENSITIESOFPRIMARYAIRPOLLUTANTS,SUCHASPARTICULATEMATTER,BLACKCARBON,ANDPOLYCYCLICAROMATICHYDROCARBONS,HAVEBEENREPORTEDINTHISREGION2023THEREGIONALAIRQUALITYISDETERIORATINGINTHEYRDREGIONANDTHEATMOSPHERICVISIBILITYHASDECREASEDSIGNIFICANTLYDURINGTHEPASTTHREEDECADES7,17THEYRDREGIONHASBEENIDENTIFIEDASAKEYAREAINTHERECENTPLANFORTHEJOINTPREVENTIONANDCONTROLOFAIRPOLLUTIONINCHINA24NANJING,THECAPITALOFJIANGSUPROVINCE,LOCATESINTHEWESTERNYRDANDITHASANAREAOFABOUT6587KM2WITHAPOPULATIONOFABOUT81MILLIONASAHIGHLYIND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