Impact of emission reduction on aerosol-radiation interaction during heavy pollution periods over Beijing-Tianjin-Hebei region in China

In December 2015, the Beijing-Tianjin-Hebei (BTH) region experienced several episodes of heavy air pollution. The government immediately issued emergency control measures to reduce the pollution, which provided a good opportunity to explore the impact of emission reduction on aerosol-radiation interaction. In this study, four tests were conducted, including the base1 simulation with emission reduction and aerosol-radiation interaction on, the base2 simulation with emission reduction and aerosol-radiation interaction off, the scenario1 simulation without emission reduction and aerosol-radiation interaction on and the scenario2 simulation without emission reduction and aerosol-radiation interaction off. We find that the aerosol-radiation interaction decreased the downward shortwave radiation and the temperature at 2 m, reduced the planetary boundary layer height (PBLH) in the region, and increased the relative humidity at 2 m, which is favorable for pollution accumulation. Our results revealed that the interaction effect due to emission reductions increased downward shortwave radiation by an average of 0–5 W/m², leading to increase in surface temperature of 0–0.05°C, increase in the daytime mean PBL high of 0–8 m, and decrease in daytime mean relative humidity at 2 m of 0.5%. We found that if there were aerosol-radiation interaction, it would enhance the effectiveness of emission control measures on air pollution control. The enhance of PM_2.5 (particulate matter less than 2.5 µm), PM₁₀ (particulate matter less than 10 µm), and NO₂ (nitrogen dioxide) emission reduction effects reached 7.62%, 6.90%, 11.62%, respectively, over this region.     

珠江三角洲冲积平原土壤重金属元素含量和来源解析

利用全国地球化学基准计划在珠江三角洲地区的22个点位上采集的44件冲积平原土壤样品,分析了As、Cd、Cr、Cu、Hg、Ni、Pb、Zn等8个重金属元素的含量特征,并利用多元统计分析方法和铅同位素示踪技术研究了重金属元素的来源.结果表明,珠三角地区冲积平原土壤8个重金属元素含量均高于全国土壤背景值,Hg在表层土壤中显著富集,As、Cd、Cu、Pb、Zn在表层土壤的含量略高于深层土壤中含量,Cr、Ni在表层土壤和深层土壤中含量相当.因子分析结果显示,土壤Cu、Cr、Ni主要受地质背景控制,Zn、Cd的高含量既与地质背景有关,也受人类活动影响,As、Pb、Hg的异常则受人为活动影响较严重.富集因子法得出8个重金属元素受人类活动影响程度大小排序为：Hg > As > Cd > Cu > Pb > Zn > Cr > Ni,当深层土壤某元素有外源输入时,会导致其富集因子偏低.铅同位素示踪结果显示,表层土壤铅含量与²⁰⁶Pb/²⁰⁷Pb呈显著的负相关关系,根据二元混合模型推测表层土壤中有超过30%的外源铅输入.综合来看,珠三角地区冲积平原土壤Hg、Cd、As、Pb受到较为严重的人为污染.     

石英ESR法在黄河现代沉积物物源示踪研究中的可行性分析

石英ESR信号示踪法作为一种新的物源示踪方法,已经被较好地应用于东亚地质历史时期风尘堆积物和现代沙尘沉降物的物源示踪研究中。首先简要回顾了石英ESR信号示踪法的研究现状,进一步基于石英ESR信号示踪法的母岩年代和结晶度原理,探讨该方法对黄河沉积物物源示踪的可行性及应用前景。     

Impacts on air pollution in urban areas

Environmental management involves controlling various forms of pollution to levels that do not pose a threat to the health of the people and the environment in general. This paper presents a framework to analyze sources of local air pollution in cities. Using an OLS model, an investigation is performed of the relationship among the concentrations of air pollutants [more precisely, concentrations of sulfur dioxide (SO₂), dust, nitric oxide (NO), nitrogen dioxide (NO₂), carbon oxide (CO) and ozone (O₃)], economic activities, and meteorology. Time series analysis leads to a model, that explains a high degree of the variance in the air pollution data. The model is applied to daily time series from three measurement stations in innsbruck, Austria. Estimation results of the model generally fit with the expected relations. Space heating influences SO₂, dust, and NO, while NO₂ levels are primarily affected by traffic. These results also indicate interdependent relations among the pollutants NO, NO₂, O₃, and CO; O₃ levels depend on temperature and sunshine.     

青岛市主要污染物减排分析研究

在分析主要污染物（COD和SO2）排放现状的基础上,结合经济社会发展情况,采用产污系数法和排放强度法2种方式,科学分析和定量预测了青岛市未来3年主要污染物的排放趋势和新增量,从产业结构调整、工程治理、监督管理3个层面合理分析了主要污染物减排量,将减排目标层层分解,并结合主要污染物存量、新增量,对未来3年中青岛市主要污染物的排放情况进行了预测。     

辽宁省产业结构对环境影响的初探

产业结构影响着一个地区社会经济以及环境等诸多方面。本文对辽宁省产业结构现状,主要行业产值及污染贡献率,以及产业结构调整对污染物排放强度变化影响进行剖析,较系统地分析了一个地区的产业结构对环境的影响,对环境管理及经济建设具有一定的借鉴意义。     

浅析铁岭市废水排放对辽河水质的影响

通过对铁岭市工业废水及生活污水排放状况的综合分析,评价出铁岭市对辽河上游段水质的影响,为辽河流域污染防治提供依据。     

走航溯源耦合在线监测分析喷涂企业排放VOCs对大气臭氧污染的影响

选择某喷涂企业附近环境空气为采样点位,在3个监测时段（5、9、11月）基于成分监测车在线监测107种挥发性有机物（VOCs）,分析环境空气中VOCs污染特征和成分,结合走航监测车进行溯源分析,利用MCM模式结合敏感性实验研究了臭氧生成机制。结果表明：5月A时段的VOCs总浓度（247.43 μg/m³）高于其他2个监测时段（134.29、107.07 μg/m³）,体现了VOCs季节性的变化趋势;3个监测时段VOCs浓度均以含氧有机物为主,其占比分别为44.36%、55.30%和37.90%,其次为芳香烃和烷烃,但不同监测时段同类VOCs占比各不相同,体现了不同季节VOCs浓度的差异性。3个监测时段均排在浓度排名前10位的物种有6种,分别为乙醇、丙酮、对/间二甲苯、苯、二氯甲烷和甲苯,说明该监测点位存在稳定污染排放源。走航溯源监测获得空气点位及附近喷涂企业内VOCs浓度和成分特征,结果显示环境大气中的VOCs主要组分来自喷涂企业厂区使用的挥发性溶剂的排放和油性漆的挥发排放。研究臭氧生成潜势（OFP）可知,芳香烃的OFP值在3个监测时段占比最高,对臭氧生成贡献较高的物种主要有对/间二甲苯、甲苯等芳香烃,乙醇和甲基丙烯酸甲酯等含氧有机物,异戊二烯和丙烯等烯烃类物种。MCM模式结果显示：5月A时段监测期间的臭氧光化学生成速率大于9月B时段和11月C时段,O₃生成过程主要受甲基过氧自由基（CH₃O₂）+NO 和过氧化羟基自由基（HO₂）+NO 控制。相对增量反应敏感性实验结果显示：3个监测时段臭氧生成均处于VOCs控制区,5月A时段,控制异戊二烯、芳香烃类物种可以大幅减少臭氧的生成,9月B时段需主要控制芳香烃和含氧有机物的排放,11月C时段则需控制芳香烃物种的排放。就VOCs单体而言,3个监测时段减少对/间二甲苯的浓度,对臭氧生成影响较大。走航溯源耦合在线监测方法可以实现臭氧污染快速原位溯源。     

内蒙古典型草原土壤及其水文过程对灌丛化的响应

基于野外观测和室内试验相结合的方法,研究了内蒙古典型草原小叶锦鸡儿灌丛化过程对土壤和土壤水文过程的影响,旨在为干旱半干旱区环境保护和恢复提供理论基础。结果表明,斑块尺度上,灌丛斑块土壤有机质和全氮含量分别是草地斑块的1.54倍和1.16倍;灌丛斑块平均沙粒、粉粒和粘粒含量是草地斑块的0.87倍、1.34倍和1.35倍;灌丛斑块土壤容重是草地斑块的0.97倍;灌丛斑块钙积层上表面出现深度是草地斑块的1.27倍。地形等自然条件也是形成土壤异质性的重要因子,坡面尺度上,灌丛和草地斑块土壤有机质、全氮、土壤容重、土壤钙积层上表面出现深度呈自坡顶向坡下方向增加的趋势。染色示踪实验表明,灌丛斑块土壤剖面湿润锋和土壤水分入渗速率分别是草地斑块的1.36倍和5.16倍,草地斑块0~10cm土层对水分的响应较敏感,而灌丛斑块25 cm以下土层对水分的响应较敏感。研究认为,灌丛化过程增强了土壤空间异质性,灌丛斑块能将土壤水分快速输送并存储于深层土壤中,灌丛斑块是土壤养分和水分富集区,灌木植物的定居和发展过程与土壤形态之间形成了正反馈。     

Effects of hydraulic retention time on net present value and performance in a membrane bioreactor treating antibiotic production wastewater

• The membrane bioreactor cost decreased by 38.2% by decreasing HRT from 72 h to 36 h. • Capital and operation costs contributed 62.1% and 37.9% to decreased costs. • The membrane bioreactor is 32.6% cheaper than the oxidation ditch for treatment. • The effluent COD also improved from 709.93±62.75 mg/L to 280±17.32 mg/L. • Further treatment also benefited from lower pretreatment investment. A cost sensitivity analysis was performed for an industrial membrane bioreactor to quantify the effects of hydraulic retention times and related operational parameters on cost. Different hydraulic retention times (72–24 h) were subjected to a flat-sheet membrane bioreactor updated from an existing 72 h oxidation ditch treating antibiotic production wastewater. Field experimental data from the membrane bioreactor, both full-scale (500 m³/d) and pilot (1.0 m³/d), were used to calculate the net present value (NPV), incorporating both capital expenditure (CAPEX) and operating expenditure. The results showed that the tank cost was estimated above membrane cost in the membrane bioreactor. The decreased hydraulic retention time from 72 to 36 h reduced the NPV by 38.2%, where capital expenditure contributed 24.2% more than operational expenditure. Tank construction cost was decisive in determining the net present value contributed 62.1% to the capital expenditure. The membrane bioreactor has the advantage of a longer lifespan flat-sheet membrane, while flux decline was tolerable. The antibiotics decreased to 1.87±0.33 mg/L in the MBR effluent. The upgrade to the membrane bioreactor also benefited further treatments by 10.1%–44.7% lower direct investment.