城市大气污染物来源特征

以北京市为案例，介绍一种包括污染物排放清单建立、环境空气质量模拟及区域环境影响分析等方法在内的城市大气污染物来源特征分析的整体技术方法，从而确定城市大气污染物的排放分布及浓度分布特征、行业排放分担率及浓度贡献、地区排放分担率及浓度贡献以及区域污染对城市环境空气质量影响等多方面特征，为城市大气污染的控制决策提供必要的理论支持。对北京市的研究结果表明：对PM10，扬尘和工业为主要当地污染源；对SO2，采暖和工业为主要当地污染源；对NOx，交通和工业为主要当地污染源；对3种主要大气污染物，石景山、朝阳南等工业区以及老城区对北京市的大气环境造成重要影响，为需要优先控制的地区；北京市周边污染源对北京环境气质量有较大影响，其中RM10的影响最大(高达47．3％)，北京市应同时加强对局地污染与区域污染的控制。     

北京市秋季大气颗粒物的污染特征研究

大气颗粒物是造成城市空气污染的重要原因之一,并已经成为我国北京等大中城市空气污染中的首要污染。为了分析北京市大气细颗粒物的污染水平及其影响因素,以大气中的PM10和PM2.5为研究对象,于2005年秋季在北京市设立了9个采样点进行采样监测,通过对所采集到的PM10和PM2.5质量浓度的对比来分析大气颗粒物的空间分布和时间变化特征,并建立起PM10和PM2.5质量浓度与风力、温度、湿度等气象条件的对应关系来分析各种气象因素对大气细颗粒物污染水平的影响。结果表明:北京市不同区域的PM10和PM2.5的质量浓度差异较大,同时,值得注意的是通过对同一地点同一采样时间大气颗粒物质量浓度的对比发现PM2.5质量浓度的空间分布并不完全同于PM10,这主要是与采样点所处的环境中不同污染源影响的强弱有关;气象条件稳定时,PM10和PM2.5质量浓度的日变化表现出一定的规律性,这种时间变化的特征主要取决于所在环境中排放的污染物变化情况;气象条件是影响PM10和PM2.5污染程度的重要因素,在一定的范围内,颗粒物质量浓度随着温度的上升而下降,随着相对湿度的升高而增大,随着风力的增强而减小。     

遂宁市大气细颗粒物污染现状及成因

通过研究遂宁市环境空气质量变化趋势、城区空气颗粒物组成及浓度变化,系统分析了遂宁市雾霾天气的污染状况及成因,并横向比较了四川省内各城市的空气质量.研究结果表明,细颗粒物(PM2.5)是遂宁市环境空气中的主要污染物.2012年遂宁市大气中PM2.5浓度值为35—119μg·m-3,平均值为68μg·m-3.2013年1—4月,PM2.5浓度值为21—120μg·m-3,达标率不到50%.尤其在2013年3月,PM2.5/PM10由62.0%—87.2%降低为45.3%.由此判断遂宁市环境空气质量主要受细颗粒物类型、气象条件以及大气污染物长距离迁移等因素影响,其中细颗粒物的最主要来源为机动车尾气排放,并提出了细颗粒物污染防治的对策措施.     

林地和湿地大气颗粒物阻滞效果研究

为了研究林地和湿地以及气象因素等对于大气颗粒物浓度的影响,于2016年5—12月在北京市奥林匹克森林公园内林地、湿地内对PM10和PM_(2.5)质量浓度以及气象数据(温度和相对湿度)进行采集。使用定量分析的方法,运用阻滞-吸附效率公式对林地和湿地阻滞率进行了比较;分析了大气不同污染背景下林地和湿地对大气颗粒物阻滞率的差异以及气象因子对大气颗粒物质量浓度的影响。研究结果表明,林地内颗粒物日变化呈现先下降后上升的趋势,13:00左右为一天之中质量浓度最低(34.6μg?m~(-3))之时,而湿地周围颗粒物日变化则在采样期间呈现下降趋势,至18:00左右质量浓度为最低(35.8μg?m~(-3))。不同空气质量等级下,林地和湿地对颗粒物的阻滞率效果不同,林地在空气质量为优时对PM_(10)和PM_(2.5)的阻滞率均最高,分别为522.7%和289.7%;湿地在空气质量等级为良时对PM_(10)的阻滞率最高(56.56%),在空气质量为重度污染时对PM_(2.5)的阻滞率为最高(74.35%)。在相同空气质量等级下,林地与湿地之间的阻滞率也存在差异:除严重污染时没有显著差异外,其余空气质量等级下林地的阻滞率显著高于湿地对大气颗粒物的阻滞率(P0.05)。此外,大气颗粒物质量浓度与气象因子之间存在显著相关性,其质量浓度与温度呈负相关,与相对湿度呈正相关。然而,阻滞率与气象因子之间没有显著相关性。研究林地与湿地的阻滞率有利于更好地配置城市中林地和湿地比率,以更加有效地改善大气环境。     

唐菖蒲对大气氟污染的生理生化反应(Physiological and Biochemical Responses of Gladiolus to Atmospheric Fluoride Pollution)

通过唐菖蒲在石家庄不同大气环境中叶片的形态、叶绿素总量、细胞膜透性以及过氧化物酶活性的变化,研究了唐菖蒲对氟污染胁迫的生理生化反应及适应调节机理.结果表明:石家庄市各监测点的大气中均存在氟污染,其污染物浓度由高到低依次为:市热电厂>元南小区>棉七生活区>阳光公园;从严重污染区到清洁区,随着污染程度的减小,唐菖蒲的叶绿素含量显著增加,细胞膜相对电导率及过氧化物酶活性明显降低.初步分析显示,唐菖蒲可作为大气氟污染的指示植物.     

北京采暖期典型区域环境空气污染特征分析

北京采暖期空气污染较非采暖期严重得多,但目前针对采暖期北京城市上风向、下风向、中心区和主干道路等典型人类活动区域的主要污染物浓度特征及其受气象条件变化影响的研究还比较缺乏,为了摸清北京市采暖期不同典型区域大气污染特征,更有针对性地制定环境空气污染防治对策,利用2014年采暖期首月(11月15日—12月14日)北京市北郊(八达岭)、南郊(永乐店)、城市中心区(天坛)、城市交通干道(永定门内大街)等典型区域的PM_(2.5)、SO_2、NO_x、O_3质量浓度监测数据和气象数据,分析4类代表性区域的环境空气污染特征和时空变化情况。结果表明,PM_(2.5)是各区域冬季主要污染物,日均质量浓度在61.75~143.81μg?m-3,总体空间分布状况为南郊最严重、城市交通干道和城市中心区次之、北郊的PM_(2.5)污染最轻,除北郊外其余监测点ρ(PM_(2.5))均超过二级标准限值。各区域的主要污染物略有不同,其中北郊ρ(SO_2)较其他区域高,白天12:00时最低(29.09μg?m-3),夜晚18:00—次日01:00持续居高(58.8~63.19μg?m-3),这与燃煤采暖等人类活动规律一致;南郊以PM_(2.5)、NO_x混合型污染为主;城市交通干道附近ρ(NO_x)和ρ(O_3)较高,表明局地光化学反应NO_x-O_3生消机制作用明显,污染物浓度变化与人类出行时间一致。气象条件对不同污染物浓度的影响存在差异,微风无持续风向、大气扩散条件较差时,PM_(2.5)呈现不断累积状态,SO_2、NO_x和O_3累积效应不明显,但其单日质量浓度峰值显著增加;北风和微风反复交替、大气扩散条件总体较好时,各监测点的SO_2、NO_x受地区性污染源排放影响波动不大,随扩散条件转差南郊ρ(PM_(2.5))会迅速增加。城市交通干道机动车排放典型污染物ρ(NO_x)及其二次污染物ρ(O_3)随着气象条件变化其峰值在日内变化显著。     

气象因素对环境空气质量达标的影响分析

以天津市为例,分析地面风场、大气层结及天气形势等主要污染气象参量的特征及其与环境空气质量的相关关系;估算高、低污染潜势的天气背景对大气污染物浓度的影响幅度;提出在天气气候分类的基础上,建立气象条件标准化分级,评估气象条件对环境空气质量影响水平的方法。研究表明:天津市采暖季高污染的天气形势出现的频率约为34%,而非采暖季高污染的天气形势出现的频率约为16%,ISCLT3模型模拟结果显示相应于相同的污染源排放数据库由于采暖季和非采暖季气象条件不同引起的SO2全市平均浓度的差异约在10%以上。污染源源强相对稳定的条件下,高污染潜势的天气背景对空气污染的加剧作用大于低污染潜势的天气背景对空气污染的减轻作用。     

基于AHP模型乌海市大气环境质量评价及合理建议

随着经济快速发展及人口迅速增长,环境问题随之而来,威胁着人们的身体健康,破坏了城市环境,阻碍了区域可持续发展.该文首先对乌海市2004~2010年大气环境质量监测数据采用层次分析法进行分析;其次构建大气环境质量分层指标体系,以SO_2、NO_2、PM_(10)三项评价因子指数为标度,构造判断矩阵,计算被比较元素的相对权重及各层元素的组合权重;最后得出大气环境质量等级排序,进而确定乌海市大气环境质量等级.通过该方法对乌海市大气环境质量进行评价,结果表明:乌海市2004~2008年大气环境质量均为三级水平,2009~2010年达到二级标准;PM10与SO_2是全市主要大气污染物,大气污染呈现煤烟型污染特征,与实际情况相符.为了提高乌海市大气环境质量,提出一些建议.     

北京市夏季近地层大气臭氧浓度的变化特征分析

臭氧是影响城市大气环境的重要污染气体之一,近地层臭氧主要是由人类活动所排放的NO和NMHC(非甲烷烃)等污染物在大气中经光化学过程产生.目前近地层臭氧浓度的形成和变化已成为大气环境研究的一个重要前沿课题.     

中国重霾过程污染气象研究进展

对近年来中国重霾污染过程的气象成因的相关研究进行了总结,从大气环流背景、边界层流场以及气象因子等方面进行综合分析,并介绍了相关区域输送对污染的影响贡献,得出关于中国重霾过程污染气象的一致结论:冬季重霾发生的典型天气条件为高空500 h Pa西风纬向环流指数高,南北气流交换不畅,利于中国中东部高空稳定形势的发展,对应近地弱高低压系统,均压场控制频繁,稳定的大气层结使污染物更易在近地累积,偏南暖湿气流则促使大量二次污染物生成;副热带高压与青藏高原高压、西风带高压并合的形势,是引起中国夏季大气环境质量恶化的主要原因;台风引起的下沉逆温稳定天气,易造成珠三角地区重霾污染。区域和局地山脉气流辐合效应使污染物较易在山麓地带聚积,海陆风和山谷风带动局地污染物的垂直输送和区域间输送。地面弱风速、风向以及高湿度是影响大气质量的直接关键因子,混合层高度与空气质量具有较强的相关性,对限制污染物的垂向有效扩散产生重要影响。数值模拟气象要素对空气质量影响贡献得到多次验证,霾预警开始发挥重要作用,区域污染的输送作用对重点城市空气质量的影响不容忽视。在重霾过程污染气象的研究还有待深化的方面包括:重视模拟研究,对污染物在大气中多尺度传输、沉降及化学循环等全周期的行为轨迹进行追踪定量,制定有针对性的污染控制技术与对策;开展大气污染的影响边界研究,辅助气象预报为特定区域空气质量保障提出即时有效的防控措施和预警方案,为提高污染控制措施的有效性奠定科学基础。     

Environmental pollution and biodiversity: Light pollution and sea turtles in the Caribbean

We examine the impact of pollution on biodiversity by studying the effect of coastal light pollution on the sea turtle population in the Caribbean. To this end we assemble a panel data set of sea turtle nesting activity and satellite-derived measures of nighttime light. Controlling for the surveyor effort, the local economic infrastructure, and spatial spillovers, we find that nighttime light significantly reduces the number of sea turtle nests. According to data on replacement costs for sea turtles raised in captivity, our result suggests that the increase in lighting over the last two decades has resulted in the loss of close to 1800 sea turtles in the Caribbean, worth up to $288 million. Incorporating our empirical estimates into a stage-structured population model, we discover that the dynamic effect of nighttime light on future generations of sea turtles is likely to be much larger, with a cost of approximately $2.8 billion for Guadeloupe alone. More generally, our study provides a new approach to valuing the cost of environmental pollution associated with species extinction.     

Organotin pollution in Malta coastal zone

The speciation of organotins in seawater, surface microlayer and sediments in the marine environment of Malta is described. Concentrations of tributyltin (TBT) in bulk seawater inside the harbours were as high as 0.3 μg Sn L^‐1 but were below detection limits (5 ng Sn L^‐1) in open sea, 1.6 km offshore. In sediments, TBT levels were highest for the yacht marinas and ranged between 0.03 and 1.5 ug Sn g^‐1. Dibutyltin is more common in the surface microlayer than TBT. Diphenyl and monophenyltin were found infrequently in bulk seawater and in sediments. Tetrasubstituted organotins, namely, Me_nBu₍₄__n)Sn, where n = 1, 2, and 3, were found frequently in TBT‐contaminated sediments (0.1–9μg Sng^‐1), in seawater and in the microlayer where concentrations as high as 140 μg Sn L^‐1 (Me₃BuSn) were measured. Direct environmental methylation of TBT and that of its debutylated analogues may play a significant role in the geochemical cycling of tin under certain environmental conditions.     

中国汞污染的来源、成因及控制技术路径分析

汞是一种能长期存在于环境且具有全球迁移性的污染物.汞污染防治是一个复杂的系统工程,涉及多部门、多领域、多行业,国家需要在政策、管理和技术等方面采取综合的战略措施推进汞污染防治.本文基于汞污染的环境和社会影响,分析了中国汞污染的来源、成因并评估了中国汞管理体系,结合中国参加全球汞公约谈判的特定背景,识别出汞污染防控的优先行业,包括汞的无意排放优先控制行业:燃煤、有色金属冶炼、汞矿开采和含汞废物处理;汞的有意使用优先控制行业:电石法聚氯乙烯生产,医疗产品、荧光灯和电池生产.本文也进一步提出了汞污染控制技术路径,包括构建汞风险管理和识别平台、完善汞管理体系、加强环境技术研发、推进绿色转型、保护环境和公众健康等.     

蔬菜主要污染问题

根据国内外有关资料及杭州市菜区调查结果，讨论了重金属、硝酸盐、农药、氟化物、苯并（ａ）芘在及塑料薄膜等对蔬菜污染的途径和危害，阐述了目前我国蔬菜所面临的主要污染问题。     

Health impacts of air pollution in China

•Impacts of air pollution on various body systems health in China were highlighted. •China’s actions to control air pollution and their effects were briefly introduced. •Challenges and perspectives of the health effects of air pollution are provided. The health effects of air pollution have attracted considerable attention in China. In this review, the status of air pollution in China is briefly presented. The impacts of air pollution on the health of the respiratory system, the circulatory system, the nervous system, the digestive system, the urinary system, pregnancy and life expectancy are highlighted. Additionally, China’s actions to control air pollution and their effects are briefly introduced. Finally, the challenges and perspectives of the health effects of air pollution are provided. We believe that this review will provide a promising perspective on the health impacts of air pollution in China, and further elicit more attention from governments and researchers worldwide.     

Review of water pollution control in China

Water resource shortage and pollution has seriously threatened the survival and development of developing countries. Because of China’s specific economical and social circumstances, complete adoption of developed countries’ experience is unrealistic. At present, China needs to develop strategies and technologies in source water pollution control and municipal environmental remediation that embrace the country’s specific need to battle the water resource problem. Among them, efficient source water pretreatment is a critical step to ensure a safe municipal water supply. Unlike developed countries, it is not yet feasible in China to treat water supplied to the household and have it meet the standard of direct drinking; therefore, it is more appropriate to refer to it as service water. As a beneficial supplement, an additional community drinking water network and household drinking water apparatus can be considered.     

Air pollution and its control in China

The rapid growth of China’s economy has led to severe air pollution characterized by acid rain, severe pollution in cities, and regional air pollution. High concentrations are found for various pollutants such as sulfur dioxides (SO₂), nitrogen oxides (NO_x), and fine particulates. Great efforts have thus been undertaken for the control of air pollution in the country. This paper discusses the development and application of appropriate technologies for reducing the major pollutants produced by coal and vehicles, and investigates air quality modeling as an important support for policy-making.     

Air pollution transport in the Balkan region and country-to-country pollution exchange between Romania, Bulgaria and Greece

US EPA Models-3 system is used for calculating the exchange of ozone pollution between three countries in southeast Europe. For the purpose, three domains with resolution 90, 30 and 10 km are chosen in such a way that the most inner domain with dimensions 90 × 147 points covers entirely Romania, Bulgaria and Greece.The ozone pollution levels are studied on the base of three indexes given in the EU Ozone Directive, mainly accumulated over threshold of 40 ppb for crops (AOT40C, period May–July), number of days with 8-h running average over 60 ppb (NOD60) and averaged daily maximum (ADM). These parameters are calculated for every scenario and the influence of each country emissions on the pollution of the region is estimated and commented.Oxidized and reduced sulphur and nitrogen loads over the territories of the three countries are also determined. The application of all scenarios gave the possibility to estimate the contribution of every country to the S and N pollution of the others and detailed blame matrixes to be build.Comparison of the ozone levels model estimates with data from the EMEP monitoring stations is made.     

Enforcement of pollution regulations in a declining industry

A regulatory agency enforcing compliance in a declining industry might recognize that certain plants would close rather than comply, imposing large costs on the local community. Data on EPA enforcement activity in the U.S. steel industry are examined for evidence of this with a two-equation model linking EPA enforcement decisions and firms' plant-closing decisions. The results indicate that the EPA directed fewer enforcement actions toward plants with a high predicted probability of closing and plants that were major employers in their community; also, plants predicted to face relatively heavy enforcement were more likely to close.     

重金属污染土壤的微生物响应

土壤微生物在受到重金属污染胁迫后，往往能够在区系组成、生理生化、遗传等方面对重金属作出响应。微生物对土壤重金属污染的上述响应可用来评价土壤的重金属污染状况，并为土壤污染的生物修复提供理论指导。文章对近年来有关重金属胁迫下土壤微生物响应的研究成果作系统综述。