城市道路隔离带绿化模式对人行道空气质量的影响评价

探讨城市道路绿化隔离带对于污染物的阻滞效应,以减少城市道路污染向两侧横向扩散,保护道路行人免受来自机动车道污染物的伤害具有重要的现实意义.因此,本研究在太原市区选择16条主干道(28个监测样点),以4种绿化植物配置模式(乔木+灌木+低绿篱、乔木+低绿篱、乔木、低绿篱)为研究对象,在无风或者微风(风速小于2 m·s-1)条件下对SO2、NOx、TSP和PM10等5种污染物进行现场监测.研究结果表明,城市道路绿化隔离带对于控制机动车道的主要污染物向非机动车道的扩散具有明显作用,绿化隔离带的植物模式差异会影响绿化带吸附和阻隔污染物能力的强弱.在此基础上,通过构建一个新的评价指标来比较各个模式在阻滞污染物方面的能力.结果显示,与其他模式相比,低绿篱模式和乔木+灌木+低绿篱模式分别对NH3和PM10具有更高的降低能力.对于SO2、NH3、NOx等气态污染物,以乔木(T)为配置模式的绿化带效果最佳,而对于TSP、PM10等颗粒污染物,乔木+灌木+低绿篱(TSH)模式的阻滞净效应最高.新评价指标能够准确定量评价绿化带植物对污染物阻滞效应能力的大小,具有较好的应用性.     

Development of a hybrid photo-bioreactor and nanoparticle adsorbent system for the removal of CO2 , and selected organic and metal co-pollutants

Fossil fuel combustion and many industrial processes generate gaseous emissions that contain a number of toxic organic pollutants and carbon dioxide (CO₂) which contribute to climate change and atmospheric pollution. There is a need for green and sustainable solutions to remove air pollutants, as opposed to conventional techniques which can be expensive, consume additional energy and generate further waste. We developed a novel integrated bioreactor combined with recyclable iron oxide nano/micro-particle adsorption interfaces, to remove CO_2, and undesired organic air pollutants using natural particles, while generating oxygen. This semi-continuous bench-scale photo-bioreactor was shown to successfully clean up simulated emission streams of up to 45% CO₂ with a conversion rate of approximately 4% CO₂ per hour, generating a steady supply of oxygen (6 mmol/hr), while nanoparticles effectively remove several undesired organic by-products. We also showed algal waste of the bioreactor can be used for mercury remediation. We estimated the potential CO₂ emissions that could be captured from our new method for three industrial cases in which, coal, oil and natural gas were used. With a 30% carbon capture system, the reduction of CO₂ was estimated to decrease by about 420,000, 320,000 and 240,000 metric tonnes, respectively for a typical 500 MW power plant. The cost analysis we conducted showed potential to scale-up, and the entire system is recyclable and sustainable. We further discuss the implications of usage of this complete system, or as individual units, that could provide a hybrid option to existing industrial setups.     

Long-term,consistent scenarios of emissions,deposition, and climate change in Europe

The aim of this study was to develop consistent scenarios of emissions, climate change and regional air pollution to enable an integrated analysis of the linkage between climate change and regional air pollution in Europe. An integrated modeling framework was developed for this purpose. The framework integrates state-of-the-art models and concepts from the area of climate change and regional air pollution and was supplemented by new modules (e.g. modeling long-term NH₃ emissions in Europe, modeling dispersion and transformation of air pollutants under climate change).Consistent climate and air pollution policies were derived, both driven by the desire to achieve certain environmental goals. According to an analysis of scenarios with various combinations of climate and regional air pollution policies the quantitatively most relevant interactions are the effect of climate change policies on the energy mix and the resulting air pollution emissions. In the long-term the global SO₂ emissions are expected to decrease (again), accordingly their effect on climate will be minor. Tentatively it can be concluded that for regional air pollution the development of the air pollutant emissions is more important than the effect of climate change on the dispersion and chemical transformation of air pollutants.     

苏锡常地区PM2.5污染特征及其潜在源区分析

利用2014年12月—2015年11月苏锡常地区国控大气环境质量监测站发布的逐时数据,分析了研究区PM_(2.5)浓度的季节变化和空间分布特征,并利用HYSPLIT模型分析了大气污染物的输送路径及苏锡常地区PM_(2.5)的潜在源区.结果表明,苏锡常地区PM_(2.5)浓度日均值变化趋势基本一致,均呈现冬季高、夏季低的规律.PM_(2.5)浓度四季空间差异显著,不同监测站之间的差异较小.四季PM_(2.5)浓度与其它污染物之间相关性显著.单位面积污染物排放量与空气质量分布的空间错位,表明该地区PM_(2.5)污染与区域性污染物迁移有较大关系.苏锡常地区气流后向轨迹季节变化特征明显,冬、春、秋季的气流主要来自西北内陆地区,夏季气流以东南和西南方向输入居多.聚类分析表明,来自内陆的污染气流和来自海洋的清洁气流是苏锡常地区两种主要输送类型,外源污染气流不仅直接输送颗粒物,还贡献了大量的气态污染物.山东南部、江苏西部、安徽东部、浙江北部及江西西北地区对苏锡常冬季PM_(2.5)浓度贡献较大,春、夏、秋季的潜在源区主要分布在苏锡常本地和周边城市.     

Ten-year emission characteristics of atmospheric pollutants from incineration of sacrificial offerings in China

The incineration of sacrificial offerings is a significant widely practiced custom that is also a kind of neglected air pollution source in China. Our results showed that the emission factors of particulate matter, SO₂, CO, NO_x, and VOCs emitted from the incineration of sacrificial offerings with purification systems were reduced by 95%, 19%, 9%, 82%, and 42%, respectively, compared with those without a purification system, revealing a significant effect of the flue gas purification system on reducing particulate matter and gaseous pollutants. The emission level of air pollutants from the incineration of sacrificial offerings remained stable before 2013 and then showed a remarkable decrease after the implementation of China´s Air Pollution Prevention Action Plan in 2013. The emissions of TSP (total suspended particulate), PM₁₀, PM_2.5, and NO_x in 2009 were 8222, 6106, 5656 and 15,878 ton, respectively, obviously higher than 3434, 2551, 2305 and 8579 ton in 2019. Such trend was affected by both the quantity of incineration and the installation rate of purification systems after the Emission Standard of Air Pollutants for Crematory (GB 13801-2015) issued in China. Distinct spatial distribution of atmospheric pollutants from incineration of sacrificial offerings was found with higher in the east and south of China than the west and north of China, which is proportional to the regional economy and population. The maximum ground-level concentration typically occurred at 0.12-0.2 km from the pollution source, posing potential health risks to people entering and exiting funeral and burial sites and nearby residents.     

基于无人机的大气细颗粒物与臭氧污染探测与溯源研究进展

近年来,中国大气细颗粒物(PM_2.5)污染的治理已取得阶段性成效,但臭氧(O₃)污染快速上升,实现PM_2.5和O₃协同控制的基础与关键是针对大气污染物的精细化探测和污染溯源.随着无人机技术和传感器技术的迅速发展,基于无人机平台的大气污染探测可以有效获得近地层的PM_2.5和O₃结构特征,并结合计算机算法对大气污染事件进行精准溯源,具有高时效性、高灵活性和高时空分辨率的特征,有助于研究人员了解区域污染物的分布、变化以及来源,为大气复合污染的协同控制提供科学依据.通过回顾传统的大气污染探测方法,总结了污染探测领域常用的无人机飞行平台类型和探测仪器,归纳了基于无人机的PM_2.5和O₃污染探测应用与相关溯源算法,并展望了无人机大气探测的未来研究方向.     

车载激光雷达对北京地区边界层污染监测研究

介绍了自行研制的车载差分激光雷达AML-2探测原理及技术参数,于2006-08、2006-09在不同天气因素条件下对北京西南郊榆垡地区大气边界层污染物O3、NO2、SO2进行了实时监测,对比分析了3种污染物浓度垂直分布及日变化特征.结果表明,无外来污染输送时,3种污染物在阴雨天气总体浓度较小,O3和NO2浓度随高度升高而减小,SO2浓度垂直分布少见此特征,但在近地面0.6 km左右有较强SO2污染层.南部气流输送对北京地区大气环境影响明显,2006-08-23～2006-08-25这次强污染气流输送高度约1～1.5 km,3种污染物浓度垂直分布及日变化特征受到干扰,北京榆垡地区边界层O3、NO2、SO2总体浓度明显上升.     

Climate and air quality-driven scenarios of ozone and aerosol precursor abatement

In addition to causing domestic and regional environmental effects, many air pollutants contribute to radiative forcing (RF) of the climate system. However, climate effects are not considered when cost-effective abatement targets for these pollutants are established, nor are they included in current international climate agreements. We construct air pollution abatement scenarios in 2030 which target cost-effective reductions in RF in the EU, USA, and China and compare these to abatement scenarios which instead target regional ozone effects and particulate matter concentrations. Our analysis covers emissions of PM (fine, black carbon and organic carbon), SO₂, NO_x, CH₄, VOCs, and CO. We find that the effect synergies are strong for PM/BC, VOC, CO and CH₄. While an air quality strategy targeted at reducing ozone will also reduce RF, this will not be the case for a strategy targeting particulate matter. Abatement in China dominates RF reduction, but there are cheap abatement options also available in the EU and USA. The justification for international cooperation on air quality issues is underlined when the co-benefits of reduced RF are considered. Some species, most importantly SO₂, contribute a negative forcing on climate. We suggest that given current knowledge, NO_x and SO₂ should be ignored in RF-targeted abatement policies.     

Natural and effective control of air pollution through plants- studies on a tree species: Holoptelea integrifolia L.

Gaseous and industrial air pollution is a serious problem throughout the world. It affects human health and plants also face negative impact on their biochemical processes, ultimately exhibited in terms of reduction in various growth parameters. The effect of air pollution is being felt even in remote areas, because pollutants can be transported over long distances. It is well known that plants absorbs gaseous/particulate pollutants and help in controlling air pollution. In order to test Holoptelea integrifolia L. as an effective and natural means for controlling air pollution present studies were undertaken. It was observed that the tree species tolerate well various pollutants present in the air, so can be used as an efficient method for minimizing of concentration pollutants to a safer level into the environment.     

A neural network-based method for short-term predictions of ambient SO2 concentrations in highly polluted industrial areas of complex terrain

A new method for short-term air pollution prediction is described, based on the neural network. It was developed for prediction for SO₂ pollution around the biggest Slovenian thermal power plant at Sostanj. Because of the high SO₂ emissions, there is a need for a reliable air pollution prediction method that would enable lowering the peaks of pollutant concentrations in critical meteorological situations. In complex topography, classical methods for air pollution modelling are not reliable enough. The results obtained by this new method are very promising.The method can also be used, with slight modifications, for other important air pollutants, the concentrations of which can be measured continuously.     

基于能源-环境情景模拟的北京市大气污染对居民健康风险评价研究

保护居民健康是北京市能源系统优化管理和大气污染治理的重要目标.本研究基于北京市的社会经济发展目标并结合相关节能减排和环保要求,针对全市2010-2020年间的能源消费分别设计了高、中、低3种约束情景,通过LEAP模型预测了全市至2020年的能源消费量与S02、NOx、PM10和PM2.5等4种主要大气污染物的排放强度,并采用泊松回归模型对3种情景下主城区居民受环境空气中这4种大气污染物的暴露危害所导致的健康风险进行了评估.结果显示:相对低约束情景,高约束情景至2020年可避免与S02、NOx、PM10和PM2.5污染相关的死亡危害分别为2663、6359、4720和4104人·a-1,而且在高约束情景下煤炭消费比重每下降1％,可相应地避免约1400人·a-1的污染急性死亡.由此建议北京市实施更加严格的节能和减排措施,严控煤炭消费总量,进一步优化能源结构,最大程度地降低能源消费导致的大气污染所产生的居民健康风险.     

兰州市大气污染对居民健康影响的研究

采用多指标多因素的综合评判方法对兰州市城区大气污染的变化规律及其给人群健康带来的影响,进行了系统的分析。并对减少和消除城市大气污染,保护人群健康的卫生学依据和防治途径进行了探讨。结果表明,室内外空气的严重污染、已对人群的健康产生了明显的影响。大气污染物中,对健康产生急性毒性作用的主要是气相污染物,其次是尘。就室内污染来讲,家庭燃煤和吸烟是诱发肺癌的重要危险因子,因此,防治和研究气相污染物对人群健康产生的综合危害,应提到与防治尘污染的同等位置上。     

Photochemical properties and source of pollutants during continuous pollution episodes in Beijing, October, 2011

Beijing sufered from serious air pollution in October, 2011 with the occurrence of three continuous episodes. Here we analyze the pollution status of particulate matter, the relationship between the gaseous pollutants, physical and chemical properties of single particles, and the profile of watersoluble ions in PM2.5during the three episodes. Regional and photochemically aged air masses, which were characterized as having high values of O3and SO2, were hypothesized to have played a dominant role in the first episode. After mixing local air masses with freshly-emitted primary pollutants, the concentration of NOx continued to increase and the size of SO4 2, NO3 and NH4 +in the particle population continued to become smaller. The amount of elemental carbon-rich and organic carbonrich particles in the scaled single particles(0.2–2 μm) and water-soluble K+in PM2.5also increased in the episodes. All the available information suggests that the biomass or fuel burning sources in or around Beijing may have had a huge impact on the last two episodes.     

Air pollution policies in Europe: efficiency gains from integrating climate effects with damage costs to health and crops

Emissions of air pollutants cause damage to health and crops, but several air pollutants also have an effect on climate through radiative forcing. We investigate efficiency gains achieved by integrating climate impacts of air pollutants into air quality strategies for the EU region. The pollutants included in this study are SO₂, NH₃, VOC, CO, NO_x, black carbon, organic carbon, PM_2.5, and CH₄. We illustrate the relative importance of climate change effects compared to damage to health and crops, as well as monetary gains of including climate change contributions. The analysis considers marginal abatement costs and compares air quality and climate damage in Euros. We optimize abatement policies with respect to both climate and health impacts, which imply implementing all measures that yield a net benefit. The efficiency gains of the integrated policy are in the order of 2.5 billion Euros, compared to optimal abatement based on health and crop damage only, justifying increased abatement efforts of close to 50%. Climate effect of methane is the single most important factor. If climate change is considered on a 20- instead of a 100-year time-scale, the efficiency gain almost doubles. Our results indicate that air pollution policies should be supplemented with climate damage considerations.     

气候变化对浙江省大气污染的影响

开展气候变化对大气污染影响的研究有利于加深对大气污染形成机理的认识.利用1996-2015年浙江省大气成分、气象观测资料,分析气候变化对大气污染的影响.结果表明,近20 a来浙江省呈年高压天气日数增多、年均气温升高、降水集中及年均净辐射、日照时数、风速、气温日较差和水汽蒸发量都下降的气候变化事实.气候变化引起大气污染扩散能力下降,1996-2015年杭州市和浙江省年均大气扩散指数分别下降了0.55和0.81,降幅分别达35.71%和42.69%.大气扩散指数与ρ（PM₁₀）、ρ（PM_2.5）及年霾日数之间呈显著负相关,当大气扩散指数增大时,大气颗粒物浓度和年霾日数均下降,反之亦然.杭州市大气扩散指数与ρ（PM₁₀）、ρ（PM_2.5）之间的相关系数分别为0.73和0.76.杭州市和浙江省大气扩散指数与年霾日数之间的相关系数分别达到0.77和0.78,T检验值则分别为28.88和30.81,说明由气候变化引起的大气扩散能力改变是影响大气污染的重要原因,但不同大气成分受气候变化的影响程度不同.影响ρ（PM₁₀）的关键气候要素是降水量、风速及相对湿度等,影响ρ（PM_2.5）的主要是辐射、气温,影响ρ（SO₂）的主要是气温,影响ρ（NO₂）及ρ（NO₃-）、ρ（NH₄+）的主要是辐射.总体来说,浙江省近20 a的气候变化事实可能有利于促进ρ（PM₁₀）、ρ（PM_2.5）、ρ（NO₂）及ρ（O₃）等上升,促进ρ（SO₂）、ρ（NO₃-）、ρ（SO₄2-）、ρ（NH₄+）等下降.      

成都市降水对大气污染物的清除效果分析

成都市受特殊地形和气候条件影响,地面风速小,静风比例高,空气湿度大,大气污染物扩散缓慢,主要靠降水的冲刷和清除作用去除大气污染物.利用2014年5月13日-2017年12月31日成都市逐小时ρ（PM_2.5）、ρ（PM₁₀）、ρ（NO₂）、ρ（O₃）、ρ（CO）、ρ（SO₂）监测数据和同期地面降水量观测数据,分析了降水前污染物质量浓度、小时最大降水量、降水持续时间及累积降水量对大气污染物清除效果的影响.结果表明:①降水对6种大气污染物的清除率随降水前污染物质量浓度的增加而增大,并且汛期降水对大气污染物的清除率大于非汛期降水.②降水对大气污染物起正清除作用,清除率随降水持续时间的增加而增大.③不同降水量对不同污染物的清除效果不同,对PM_2.5、PM₁₀、NO₂、CO和SO₂的清除率随降水量的增加而逐渐增大,对O₃的清除效果相差不大且清除率均较大;小时最大降水量对PM_2.5、PM₁₀、NO₂、O₃、CO、SO₂的清除率平均值分别为29.48%、26.95%、22.02%、26.87%、11.94%、28.75%,累积降水量的清除率平均值分别为31.64%、30.66%、24.38%、26.31%、13.89%、32.91%,其中CO不易溶于水,降水对其清除作用明显小于其他几种污染物.研究显示,降水对大气污染物的清除作用显著,对SO₂、PM_2.5和PM₁₀的清除效果较好,而对CO的清除效果较差.      

2015年12月北京市空气重污染过程分析及污染源排放变化

2015年12月,北京市及周边地区连续多次出现重污染天气.在此期间,北京市空气重污染应急指挥部两次发布红色预警.为厘清该月重污染的发生过程、生消变化,测算了应急措施下的污染源排放变化情况,并采用数值模拟和地面观测相结合的分析方法,对重污染的形成原因进行初步分析,同时对应急措施的环境效果进行评估.结果表明:1虽然2015年12月北京市主要大气污染物排放量较去年同期有所下降,但排放强度仍然较大,是重污染过程的内因;气象扩散条件不利是重要的外因,地面风速弱,大气稳定度高,相对湿度高,边界层高度降低,源排放及气象因素共同导致了此轮重污染过程.2红色预警应急措施可实现污染物日排放强度减少36%左右,PM_2.5浓度下降11%~21%,预警的应急措施不能扭转重污染的态势,但对于缓解PM_2.5污染加重趋势有明显的效果.3在重污染天气下,污染物仍在大气中累积,应急措施最明显的效果发生在实施后的48~72 h后,因此建议在PM_2.5浓度快速上升前36~48 h实施减排措施,从而对空气质量预报准确性提出更高的要求.     

夏季长三角地区臭氧非线性响应曲面模型的建立及应用

2013年8月上旬,长三角地区发生了一次大范围高浓度臭氧污染事件.本研究基于WRF-CMAQ空气质量模型系统,结合长三角地区大气污染物排放清单,构建了臭氧与其前体物之间的非线性响应曲面模型(Response surface modeling,RSM).基于RSM探讨了长三角地区O_3化学的敏感性特征,分析了上海市O_3的来源并预测不同情景下O_3的变化,提出O_3污染的最优控制方案.研究结果表明,长三角地区夏季O3主控因素区域差别较大,上海环科院、杭州卧龙桥、南京玄武湖等城区点位属于VOC控制型;徐州铜山、合肥肥西、丽水青田等郊区属于NOx控制型.O_3的敏感性特征在不同浓度水平下也呈现较大差异,随着O_3浓度水平的升高,各地区NOx敏感性均有所增加.从区域来源来看,远距离传输对平日上海O_3贡献较大,占50%以上;而在O_3污染日,本地及区域贡献为72.1%,而远距离传输贡献下降至27.9%.快速预测了110组减排情景,表明在本地及区域前体物均减排70%的情况下,2013年8月上海O_3浓度能完全达标.     

大气环境容量理论与核算方法演变历程与展望

大气环境容量在我国一直被作为环境管控措施制订和空气质量精细化管理的重要依据,相关研究是当前的热点.通过研究大气环境容量的相关文献,结合国家、区域及城市的相关实践工作,对国内外环境容量理论和核算方法的发展特征进行了系统的总结和评述.在综述大气环境容量概念的基础上,分析了其具备的自然属性、社会属性及资源属性三重特征.结合我国大气环境问题和大气污染管理模式的演变历程,分析了大气环境容量理论和实践在引入与探索期、发展与实践期、停滞期和快速发展期等4个不同阶段的发展特点.针对我国先后出现的以煤烟型污染、酸雨型污染和复合型污染为主要特征的3种大气环境问题,分析了大气环境容量的内涵及核定思路.以A值法、线性优化法、模型模拟法为重点,总结了不同核算方法的优点和不足,发现了模型模拟法可以兼顾气象、地形等自然因素和污染源等人为因素对于大气环境容量的影响,并可以反映复杂的大气物理化学过程,更适合以PM_2.5、O₃等复合污染为约束的环境容量的核算.最后,结合环境管理的要求,建议在以下三方面加强研究:①以多种污染指标达标为约束的大气环境容量核算方法;②典型重污染时段的大气环境容量核算方法;③改进模型模拟和多目标优化耦合技术,探讨在空气质量、健康损害、生态破坏、气候变化等多种因素约束下的大气环境容量核算方法.      

Effects of nitrogen dioxide and its acid mist on reactive oxygen species production and antioxidant enzyme activity in Arabidopsis plants

Nitrogen dioxide (NO₂) is one of the most common and harmful air pollutants. To analyze the response of plants to NO₂ stress, we investigated the morphological change, reactive oxygen species (ROS) production and antioxidant enzyme activity in Arabidopsis thaliana (Col-0) exposed to 1.7, 4, 8.5, and 18.8 mg/m³ NO₂. The results indicate that NO₂ exposure affected plant growth and chlorophyll (Chl) content, and increased oxygen free radical (O₂⁻) production rate in Arabidopsis shoots. Furthermore, NO₂ elevated the levels of lipid peroxidation and protein oxidation, accompanied by the induction of antioxidant enzyme activities and change of ascorbate (AsA) and glutathione (GSH) contents. Following this, we mimicked nitric acid mist under experimental conditions, and confirmed the antioxidant mechanism of the plant to the stress. Our results imply that NO₂ and its acid mist caused pollution risk to plant systems. During the process, increased ROS acted as a signal to induce a defense response, and antioxidant status played an important role in plant protection against NO₂/nitric acid mist-caused oxidative damage.