Atmospheric Environment最新文献_第6页

A comparison of meteorological normalization of PM2.5 by multiple linear regression, general additive model, and random forest methods 通过多元线性回归、一般加法模型和随机森林方法对 PM2.5 气象归一化进行比较

IF 4.2 2区环境科学与生态学 Q2 ENVIRONMENTAL SCIENCES

Atmospheric Environment

Pub Date : 2024-10-03 DOI: 10.1016/j.atmosenv.2024.120854

Ling Qi , Haotian Zheng , Dian Ding , Shuxiao Wang

PM_2.5 is still one of the major atmospheric pollutants worldwide. Extracting contributions of anthropogenic emission control from the observed PM_2.5 variations (PM_{2.5_anth}), which are also strongly affected by meteorological changes, is critical for effective pollution control. Statistical and machine learning methods are usually used for such purpose, but the effectiveness of these methods is hard to evaluate due to the lack of observed anthropogenic contributions. In this study, we use the chemical transport model GEOS-Chem standard simulation to mimic PM_2.5 variability in the real atmosphere, and use the model simulation with fixed meteorological fields as the “true value” for PM_{2.5_anth}. We evaluate the effectiveness of three methods in meteorological normalization of PM_2.5 on decadal (2006–2017) and synoptic (one month) scale: multiple linear regression (MLR), general additive model (GAM), and random forest (RF) algorithm. For meteorological normalization of PM_2.5 on decadal scale, 67–72% of the MLR simulations show positive biases and 56–75% of the RF simulations show negative biases. The “true value” of PM_{2.5_anth} falls within the range of meteorological normalization results of the three methods in most cases, but consistent positive/negative biases are observed in ∼30% of the cases, when meteorological changes dominate PM_2.5 variability. In addition, the biases are correlated to the contribution of meteorological changes. As such, multiple statistical or machine learning methods are recommended to quantify the uncertainties associated with method choice in cases anthropogenic emission changes dominate PM_2.5 variability. On synoptic scale, RF performs better in reproducing the daily variations of the PM_{2.5_anth} differences than MLR (GAM) in all (83% of) the cases, and is recommended for meteorological normalization of PM_2.5 in short-term in eastern China.

PM2.5 仍然是全球主要大气污染物之一。从观测到的 PM2.5 变化（PM2.5_anth）中提取人为排放控制的贡献对于有效的污染控制至关重要，而 PM2.5 也受到气象变化的强烈影响。统计和机器学习方法通常用于此目的，但由于缺乏观测到的人为贡献，这些方法的有效性很难评估。在本研究中，我们使用化学传输模型 GEOS-Chem 标准模拟来模仿真实大气中 PM2.5 的变化，并使用固定气象场的模型模拟作为 PM2.5_anth 的 "真实值"。我们评估了在十年尺度（2006-2017 年）和同步尺度（一个月）上对 PM2.5 进行气象归一化的三种方法的有效性：多元线性回归（MLR）、一般加法模型（GAM）和随机森林算法（RF）。对于十年尺度 PM2.5 的气象归一化，67-72% 的 MLR 模拟显示正偏差，56-75% 的 RF 模拟显示负偏差。在大多数情况下，PM2.5_anth 的 "真实值 "在三种方法的气象归一化结果范围内，但在气象变化主导 PM2.5 变化的情况下，有 30% 的情况下观察到一致的正/负偏差。此外，偏差与气象变化的贡献相关。因此，在人为排放变化主导 PM2.5 变异的情况下，建议采用多种统计或机器学习方法来量化与方法选择相关的不确定性。在天气尺度上，RF 在所有（83% 的）情况下都比 MLR（GAM）更好地再现了 PM2.5_anth 差值的日变化，因此推荐用于中国东部地区 PM2.5 的短期气象归一化。

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引用次数: 0

Spatial heterogeneity of volatile organic compound pollution in a typical industrial park based on multi-point online monitoring: Pollution characteristics, health risks, and priority-controlled species 基于多点在线监测的典型工业园区挥发性有机化合物污染的空间异质性：污染特征、健康风险和重点控制物种

IF 4.2 2区环境科学与生态学 Q2 ENVIRONMENTAL SCIENCES

Atmospheric Environment

Pub Date : 2024-10-02 DOI: 10.1016/j.atmosenv.2024.120852

Mengjuan Han , Ge Ren , Xinna Zhao , Xiaodong Zhang , Hong Lin , Dan Liu , Lei Wang

Emissions from industrial parks are crucial sources of ambient volatile organic compound (VOC) pollution, characterized by high concentrations, complex compositions, dispersed emission sources, and uneven spatial distribution. To better understand and address this issue, it is crucial to analyze the spatial differences in VOC pollution and associated health risks through multi-point monitoring. In this study, we established four online monitoring sites in a typical industrial park in Kaifeng, China. We monitored 115 VOC species and found significant differences in the concentration and chemical composition of total VOCs (TVOCs) among the four sites. Two sites were primarily composed of halohydrocarbons (49.80% and 41.21%), while the other two sites had a higher proportion of aromatics (54.78% and 39.03%). Acetaldehyde was the main contributor to ozone formation potential (OFP) at one site, while toluene was associated with the other three sites. The site with the highest VOC concentration and OFP also showed the highest secondary organic aerosol formation potential (SOAP). In terms of health risk assessment, acrolein posed a non-carcinogenic risk at all sites, but there were disparities in the carcinogenic risk among the four sites. 1,2-Dichloroethane at one site exceeded the definite risk limit, while 1,2-dibromoethane and chloroform were considered probable risk species at another site. Considering both the environmental impact and health risk, we used entropy-weighting to calculate a comprehensive control index (CCI). This index identified 1,2-dichloroethane as the Level Ⅰ controlled pollutant species at two sites, and toluene at the other two sites. This study highlights the spatial heterogeneity in VOC pollution and health risks within the industrial park, providing valuable insights for targeted pollution control strategies.

工业园区的排放物是环境挥发性有机化合物（VOC）污染的重要来源，具有浓度高、成分复杂、排放源分散、空间分布不均等特点。为了更好地理解和解决这一问题，通过多点监测分析挥发性有机化合物污染的空间差异及相关健康风险至关重要。在本研究中，我们在中国开封的一个典型工业园区建立了四个在线监测点。我们监测了 115 种挥发性有机化合物，发现四个监测点之间总挥发性有机化合物（TVOC）的浓度和化学成分存在显著差异。其中两个地点主要由卤代烃组成（分别为 49.80% 和 41.21%），而另外两个地点的芳烃比例较高（分别为 54.78% 和 39.03%）。乙醛是一个地点臭氧形成潜能值（OFP）的主要成因，而甲苯则与其他三个地点有关。挥发性有机化合物浓度和臭氧形成潜能值最高的地点，其二次有机气溶胶形成潜能值也最高。在健康风险评估方面，所有地点的丙烯醛都具有非致癌风险，但四个地点的致癌风险存在差异。一个地点的 1,2-二氯乙烷超过了明确的风险限值，而另一个地点的 1,2-二溴乙烷和氯仿被认为是可能存在风险的物种。考虑到环境影响和健康风险，我们使用熵权法计算了综合控制指数（CCI）。该指数确定 1,2-二氯乙烷在两个地点为Ⅰ级受控污染物，甲苯在另外两个地点为Ⅰ级受控污染物。这项研究强调了工业园区内挥发性有机化合物污染和健康风险的空间异质性，为有针对性的污染控制策略提供了宝贵的见解。

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引用次数: 0

Gaseous and aerosol emissions from open burning of tree pruning and hedge trimming residues: Detailed composition and toxicity 露天焚烧树木修剪和绿篱修剪残留物产生的气体和气溶胶排放：详细成分和毒性

IF 4.2 2区环境科学与生态学 Q2 ENVIRONMENTAL SCIENCES

Atmospheric Environment

Pub Date : 2024-10-01 DOI: 10.1016/j.atmosenv.2024.120849

A. López-Caravaca , E.D. Vicente , D. Figueiredo , M. Evtyugina , J.F. Nicolás , E. Yubero , N. Galindo , Jiří Ryšavý , C.A. Alves

Gaseous and PM₁₀ samples were collected during the open burning of pruning residues (olive branches and garden waste) and characterised by distinct analytical techniques to obtain comprehensive chemical emission profiles. Oxidative potential (dithiothreoitol and ascorbic acid assays) and cell viability tests were also performed with the aim of evaluating aerosol toxicity. Emission factors (EFs) were as follows (g kg⁻¹ biofuel, dry basis): 1537–1672 for CO₂, 41.9–80 for CO, 2.74–6.6 for CH₄, 0.89–3.51 for ethane, 0.79–1.78 for ethylene and 0.56–3.47 for formaldehyde. Emissions of PM₁₀, organic carbon (OC) and elemental carbon (EC) were in the ranges 8–41, 3–18, and 0.4–1.5 g kg⁻¹ biofuel, dry basis, respectively. OC accounted for 35–45% of the total PM₁₀ mass, while EC contributed between around 3% and 5%. WSOC/OC ratios varied from 0.4 to 0.6, revealing that a substantial portion of the carbon emitted was hydrosoluble. Water soluble ions constituted around 8–21% of the PM₁₀ mass, with potassium and chloride as the most abundant ions in all samples. Levoglucosan, widely used a reliable biomass burning tracer, was found in significant amounts in all samples (up to 1.2% of the PM₁₀ mass). Retene, generally pointed out as a biomass combustion biomarker, was the predominant PAH. WSOC and some PAHs showed significant positive correlations with the intrinsic OP measured with the DTT assay, while the OP^AA was significantly correlated with some trace metals, such as Fe or Ni. All samples significantly reduced the viability of alveolar epithelial cells.

在露天焚烧修剪残留物（橄榄枝和园艺垃圾）的过程中收集了气体和 PM10 样本，并采用不同的分析技术对其进行了定性，以获得全面的化学排放概况。为了评估气溶胶的毒性，还进行了氧化潜能（二硫苏糖醇和抗坏血酸测定）和细胞活力测试。排放系数（EFs）如下（克/千克-1 生物燃料，干基）：二氧化碳为 1537-1672，一氧化碳为 41.9-80，甲烷为 2.74-6.6，乙烷为 0.89-3.51，乙烯为 0.79-1.78，甲醛为 0.56-3.47。可吸入颗粒物（PM10）、有机碳（OC）和元素碳（EC）的排放量范围分别为 8-41、3-18 和 0.4-1.5 克/千克-1 生物燃料（干基）。OC 占 PM10 总量的 35-45%，而 EC 约占 3%-5%。WSOC/OC 比率从 0.4 到 0.6 不等，表明排放的碳有很大一部分是水溶性的。水溶性离子约占 PM10 质量的 8%-21%，其中钾离子和氯离子在所有样本中含量最高。左旋葡聚糖被广泛用作可靠的生物质燃烧示踪剂，在所有样本中都发现了大量左旋葡聚糖（最多占 PM10 质量的 1.2%）。通常被视为生物质燃烧生物标志物的 Retene 是最主要的多环芳烃。WSOC 和一些 PAHs 与用 DTT 分析法测量的固有 OP 呈显著正相关，而 OPAA 则与一些痕量金属（如铁或镍）呈显著相关。所有样本都会明显降低肺泡上皮细胞的活力。

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引用次数: 0

Surface exchange of HONO over paddy fields in the Pearl River Delta, China 中国珠江三角洲稻田上空的 HONO 表面交换

IF 4.2 2区环境科学与生态学 Q2 ENVIRONMENTAL SCIENCES

Atmospheric Environment

Pub Date : 2024-10-01 DOI: 10.1016/j.atmosenv.2024.120853

Baobin Han , Yingjie Zhang , Wenda Yang , Yihang Yu , Ke Tang , Yujie Tian , Yucheng Gong , Bingna Chen , Peng Cheng

Soil can release HONO, affecting atmospheric oxidation and tropospheric chemistry processes through the production of hydroxyl radicals (OH) and nitric oxide (NO) via photolysis. However, there is limited field observation of HONO flux, hindering a comprehensive understanding of its emission mechanisms. In this study, a dual open-top chambers system combined with a long path absorption photometer (LOPAP) was employed to measure HONO flux from paddy fields in the Pearl River Delta area (PRD), showing good reproducibility and effectivity to mitigate greenhouse effects. The average HONO flux was 0.77 ± 0.72 ng N m⁻² s⁻¹, displaying a diurnal pattern of higher fluxes during the day and lower fluxes at night, similar to previous flux observations. A strong linear correlation between the HONO flux with the product of NO₂ and solar radiation (R² = 0.90) suggests that surface reactions involving NO₂ and sunlight may dominate HONO production from the paddy fields, surpassing microbial activity within the soil. Given the diversity of field environments, more field observations are needed for assessing emission rates of HONO and understanding underlying mechanisms.

土壤会释放 HONO，通过光解产生羟基自由基（OH）和一氧化氮（NO），从而影响大气氧化和对流层化学过程。然而，对 HONO 通量的实地观测有限，妨碍了对其排放机制的全面了解。本研究采用了双开顶室系统结合长路径吸收光度计（LOPAP）来测量珠江三角洲（PRD）地区水稻田中的 HONO 通量，显示了良好的重现性和减缓温室效应的有效性。HONO 通量的平均值为 0.77 ± 0.72 ng N m-2 s-1，呈现出昼高夜低的昼夜变化规律，与之前的通量观测结果相似。HONO 通量与二氧化氮和太阳辐射的乘积（R2 = 0.90）之间存在很强的线性相关，这表明涉及二氧化氮和阳光的地表反应可能主导了水稻田中 HONO 的产生，超过了土壤中的微生物活动。鉴于田间环境的多样性，需要进行更多的实地观测，以评估 HONO 的排放率并了解其潜在机制。

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引用次数: 0

Ground ozone rise during the 2022 shanghai lockdown caused by the unfavorable emission reduction ratio of nitrogen oxides and volatile organic compounds 氮氧化物和挥发性有机化合物的不利减排比例导致 2022 年上海封锁期间地面臭氧上升

IF 4.2 2区环境科学与生态学 Q2 ENVIRONMENTAL SCIENCES

Atmospheric Environment

Pub Date : 2024-10-01 DOI: 10.1016/j.atmosenv.2024.120851

Qian Wang , Yuewu Li , Fangqian Zhong , Wanqi Wu , Hongliang Zhang , Rong Wang , Yusen Duan , Qingyan Fu , Qing Li , Lin Wang , Shaocai Yu , Abdewahid Mellouki , David C. Wong , Jianmin Chen

Ground-level ozone (O₃) pollution has shifted from a scientific issue to a key focus of governmental action in China. In recent years, the concentration of NO₂ in Shanghai has shown a decreasing trend of 3.7% annually, but ozone concentrations have exhibited significant interannual variability, particularly with a noticeable increase in 2022. This study focuses on investigating the mechanisms behind the increase in ozone concentration during the COVID-19 pandemic control period in 2022 in Shanghai, utilizing a combination of ground observation data, observation-based models, and chemical transport models for analysis. The results indicate that during the lockdown period, the mean values of daily maximum 8-h average O₃ concentrations (MDA8 O₃) in Shanghai increased by 17 μg/m³, with emission-related factors contributing 65.3%, primarily due to a blanket reduction in VOCs and NOx emissions during the lockdown, with a reduction ratio close to 1:1. However, this reduction ratio and intensity are not sufficiently reasonable to alleviate ozone pollution. Meanwhile, adverse meteorological conditions further exacerbated this effect, contributing 34.7%, with temperature rise having the greatest impact. Results from the chemical transport model show that with the total reduction in NOx and VOCs emissions unchanged, the greater the reduction in VOC emissions and the better the reduction effect on ozone pollution, reducing MDA8 O₃ by approximately 10 μg/m³, especially for the control of reactive compounds such as alkenes, aromatics, and OVOCs. However, if the reduction ratio of NOx is greater than that of VOCs, ozone concentrations may not decrease but instead increase. This indicates that ozone concentration is influenced not only by the intensity of emissions reduction but also by the ratio of emissions reduction between NOx and VOCs. Our study emphasizes the critical role of carefully designed strategies, focusing on controlling the ratio of VOCs to NOx and increasing the intensity of VOCs reduction, to effectively alleviate ozone pollution in urban areas.

在中国，地面臭氧（O3）污染已从一个科学问题转变为政府行动的重点。近年来，上海的二氧化氮浓度呈现出每年下降 3.7% 的趋势，但臭氧浓度却呈现出明显的年际变化，尤其是在 2022 年出现了明显的上升。本研究结合地面观测数据、基于观测的模型和化学传输模型进行分析，重点研究 2022 年 COVID-19 大流行控制期间上海臭氧浓度上升的机理。结果表明，在封锁期间，上海臭氧日最大 8 小时平均浓度（MDA8 O3）均值增加了 17 μg/m³，其中排放相关因素占 65.3%，主要原因是封锁期间 VOCs 和 NOx 排放全面减少，减少比例接近 1:1。然而，这一减排比例和强度对于缓解臭氧污染来说还不够合理。同时，不利的气象条件进一步加剧了这一影响，占 34.7%，其中气温升高的影响最大。化学传输模型的结果表明，在氮氧化物和挥发性有机物排放总量削减比例不变的情况下，挥发性有机物排放削减比例越大，对臭氧污染的削减效果越好，可使 MDA8 O3 降低约 10 μg/m³ ，尤其是对烯烃、芳烃和 OVOCs 等活性化合物的控制效果更好。但是，如果氮氧化物的还原率大于挥发性有机化合物的还原率，臭氧浓度可能不会降低，反而会升高。这表明，臭氧浓度不仅受减排强度的影响，还受氮氧化物和挥发性有机化合物减排比例的影响。我们的研究强调了精心设计的战略对于有效缓解城市地区臭氧污染的关键作用，这些战略的重点是控制挥发性有机化合物与氮氧化物的比例以及提高挥发性有机化合物的减排强度。

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引用次数: 0

Provenance of mineral dust deposited on Antarctica over the last sixty years by strontium isotopic analysis of snow from Dome C 通过对穹顶 C 的雪进行锶同位素分析了解过去六十年沉积在南极洲的矿物尘埃的来源

IF 4.2 2区环境科学与生态学 Q2 ENVIRONMENTAL SCIENCES

Atmospheric Environment

Pub Date : 2024-09-29 DOI: 10.1016/j.atmosenv.2024.120850

Maria Alessia Vecchio , Marta Costas-Rodríguez , Laura Caiazzo , Federica Bruschi , Kasper Hobin , Frank Vanhaecke , Marco Grotti

The strontium (Sr) concentration and ⁸⁷Sr/⁸⁶Sr isotope ratio have been determined in 132 snow pit samples collected at Dome C, on the East Antarctic Plateau, corresponding to the period 1958–2019, and in 12 surface snow samples collected at the same site in 2016–2017. The average Sr concentration was 8.1 ± 5.7 pg g⁻¹ (mean ± SD) in snow pit samples and 10.1 ± 8.0 pg g⁻¹ (mean ± SD) in surface snow, without any significant temporal trend. The ⁸⁷Sr/⁸⁶Sr isotope ratio showed small variations (<0.15%), with an average ⁸⁷Sr/⁸⁶Sr value of 0.7094 ± 0.0010 (mean ± SD) in snow pit and 0.7103 ± 0.0004 (mean ± SD) in surface snow samples. These results seem to suggest that no change in the source(s) of mineral dust has occurred throughout the period investigated.

Comparison of the ⁸⁷Sr/⁸⁶Sr isotope ratio of the snow samples with those of potential source areas suggests that the mineral dust reaching the East Antarctic plateau over the last decades is of a mixed origin, with a contribution from Patagonia and one or more other source(s) having a more radiogenic Sr isotopic signature, with a major fraction coming from South Australia.

研究人员测定了1958-2019年期间在东南极高原圆顶C采集的132个雪坑样本和2016-2017年在同一地点采集的12个表层雪样本中的锶（Sr）浓度和87Sr/86Sr同位素比值。雪坑样品中的平均 Sr 浓度为 8.1 ± 5.7 pg g-1（平均值±标度），表层雪中的平均 Sr 浓度为 10.1 ± 8.0 pg g-1（平均值±标度），没有明显的时间趋势。87Sr/86Sr 同位素比值变化较小（<0.15%），雪坑样品中 87Sr/86Sr 的平均值为 0.7094 ± 0.0010（平均值 ± SD），表层雪样品中 87Sr/86Sr 的平均值为 0.7103 ± 0.0004（平均值 ± SD）。雪样的 87Sr/86Sr 同位素比值与潜在来源地区的 87Sr/86Sr 同位素比值的比较表明，过去几十年中到达南极东部高原的矿物尘埃是混合来源的，其中一部分来自巴塔哥尼亚，另一部分或更多的来源具有更具放射性的 Sr 同位素特征，其中主要部分来自南澳大利亚。

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引用次数: 0

Sources and formation of fine size-fractionated particulate matters during smoke haze episode in Northern Thailand in relation to polycyclic aromatic hydrocarbons and carbonaceous composition 泰国北部烟霾事件中细粒度分馏颗粒物的来源和形成与多环芳烃和碳质成分的关系

IF 4.2 2区环境科学与生态学 Q2 ENVIRONMENTAL SCIENCES

Atmospheric Environment

Pub Date : 2024-09-28 DOI: 10.1016/j.atmosenv.2024.120845

Nuttipon Yabueng , Wittawat Insian , Somporn Chantara

Air pollution in upper Southeast Asia (SEA) has become critical particularly regarding atmospheric particles. This study aims to investigate the sources and formation of fine size-fractionated particulate matters (FSPMs), as well as their potential impact on climate. Particulate matter in three size ranges (2.1–1.1 μm, 1.1–0.65 μm, and 0.65–0.43 μm) was collected using cascade impactors in rural Chiang Dao (CD) and urban Chiang Mai (CM) during the smoke haze period (March–April 2019) in Chiang Mai, Thailand. The average concentration of FSPM was approximately 1.3 times higher in rural CD (88 ± 34 μg/m³) than in urban CM (66 ± 26 μg/m³). Both areas showed significantly higher concentrations of finer particles, with rural CD detecting 41 ± 17 μg/m³ (46% of FSPM) and urban CM presenting 27 ± 11 μg/m³ (41% of FSPM). Total carbon (TC) concentrations, including organic carbon (OC) and elemental carbon (EC), showed the same pattern as PMs. The most abundant fractions, including OC3 (32–45% of total OC) and EC1 (91–100% of total EC) in FSPM samples, particularly in fine particles (PM1), suggest that biomass burning was the primary source. Source classification based on diagnostic ratios of polycyclic aromatic hydrocarbons (PAHs), OC/EC ratios, combined with primary and secondary formations, revealed that PM_2.1-1.1 was influenced by biomass burning and secondary organic carbon (SOC), while PM_0.65-0.43 originated from both SOC and vehicular emissions. PM_1.1-0.65 in the rural area was probably caused by SOC and other mixed sources, whereas SOC and vehicular emissions were the main source in urban CM. With respect to the effective carbon ratio (ECR), lower values were observed in finer particles (0.37 ± 0.15 in rural CD and 0.36 ± 0.38 in urban CM), suggesting enhanced light-absorbing properties of fine particulate matter during the haze period in the upper SEA region.

东南亚（SEA）上游的空气污染已变得十分严重，尤其是大气颗粒物。本研究旨在调查细颗粒物（FSPMs）的来源和形成，以及它们对气候的潜在影响。在泰国清迈的烟霾期（2019 年 3 月至 4 月），使用级联冲击器在清道农村（CD）和清迈城市（CM）收集了三种粒径范围（2.1-1.1 μm、1.1-0.65 μm 和 0.65-0.43 μm）的颗粒物。清道农村地区的可吸入颗粒物平均浓度（88 ± 34 μg/m³）是清迈城市地区（66 ± 26 μg/m³）的约 1.3 倍。两个地区的细颗粒物浓度都明显较高，农村 CD 检测到的细颗粒物浓度为 41 ± 17 μg/m³（占可吸入颗粒物的 46%），城市 CM 检测到的细颗粒物浓度为 27 ± 11 μg/m³（占可吸入颗粒物的 41%）。总碳（TC）浓度，包括有机碳（OC）和元素碳（EC），显示出与可吸入颗粒物相同的模式。在可吸入颗粒物样本中，特别是在细颗粒物（PM1）中，含量最高的组分包括 OC3（占 OC 总量的 32-45%）和 EC1（占 EC 总量的 91-100%），这表明生物质燃烧是主要来源。根据多环芳烃（PAHs）的诊断比率、OC/EC 比率以及一次和二次形成进行的来源分类显示，PM2.1-1.1 受生物质燃烧和二次有机碳（SOC）的影响，而 PM0.65-0.43 则源自二次有机碳和车辆排放。农村地区的 PM1.1-0.65 可能是由 SOC 和其他混合源造成的，而 SOC 和车辆排放则是城市 CM 的主要来源。在有效碳比（ECR）方面，细颗粒物的有效碳比值较低（农村CD为0.37±0.15，城市CM为0.36±0.38），这表明在东南欧上游地区的雾霾期间，细颗粒物的光吸收特性增强。

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引用次数: 0

Inversing NOx emissions based on an optimization model that combines a source-receptor relationship correction matrix and monitoring data: A case study in Linyi, China 基于结合源-受体关系修正矩阵和监测数据的优化模型，反演氮氧化物排放：中国临沂案例研究

IF 4.2 2区环境科学与生态学 Q2 ENVIRONMENTAL SCIENCES

Atmospheric Environment

Pub Date : 2024-09-28 DOI: 10.1016/j.atmosenv.2024.120848

Mengzhen Li , Jianlei Lang , Ying Zhou , Zeya Shen , Dongsheng Chen , Jia Li , Shuiyuan Cheng

Inversion based on observational data and the source-receptor relationship (SRR) simulated by an air quality model is an effective means to estimate NO_x emissions. However, the SRR bias induced by the inherent uncertainty of the simulated model leads to potential errors in the inversed emissions, but this is seldom considered in NO_x inversion. In this study, we constructed an inversion model based on the SRR correction (IMSC) by introducing a correction matrix, combined with joint regularization scheme and genetic algorithm. We innovated the dynamic acquisition method of center-restricted parameters for the correction matrix, combined this with other parts of the IMSC, attaining the multi-month and multi-region pollutant emission inversion. Hypothetical examples demonstrated that the IMSC effectively corrected the SRR and accurately estimated the NO_x emissions. The IMSC was used to estimate Linyi county-level NO_x emissions for January, April, July and October (typical months) during 2020 and 2021. An inversion model without SRR correction (IMWSC) was developed for comparison with the IMSC. Results showed that the IMSC more accurately, robustly, and reasonably estimated NO_x emissions. Compared to the IMWSC, the IMSC improved the mean correlation between NO_x emissions and NO₂ observational concentrations by 25.0%, enhancing the correlation between NO_x emissions and NO₂ column concentrations by 111.3%. The similar NO_x emission change ratios (σ_average = 5.1%) between the typical months in 2021 and 2020 among the different counties indicated a more robust performance of the IMSC than the IMWSC (σ_average = 55.2%). In addition, the NO_x emissions inversed by the IMSC also showed better consistency with social activity levels (i.e., electricity consumption). The typical monthly Linyi's county-level NO_x emission characterization was also studied. NO_x emissions were lower in April, July, and October 2021 than the same period in 2020 due to COVID-19 and pollution controls. This study provides strategies for swiftly and accurately estimating pollutant emissions.

基于观测数据和空气质量模型模拟的源-受体关系（SRR）进行反演是估算氮氧化物排放量的有效方法。然而，模拟模型固有的不确定性所引起的 SRR 偏差会导致反演排放的潜在误差，但这在氮氧化物反演中很少被考虑。在本研究中，我们通过引入修正矩阵，结合联合正则化方案和遗传算法，构建了基于 SRR 修正的反演模型（IMSC）。我们创新了修正矩阵中心限制参数的动态获取方法，并将其与 IMSC 的其他部分相结合，实现了多月、多区域污染物排放反演。假设实例表明，IMSC 有效修正了 SRR，并准确估算了氮氧化物排放量。利用 IMSC 估算了 2020 年和 2021 年 1 月、4 月、7 月和 10 月（典型月份）临邑县的氮氧化物排放量。为了与 IMSC 进行比较，还开发了不带 SRR 修正的反演模型（IMWSC）。结果表明，IMSC 更准确、稳健、合理地估计了氮氧化物排放量。与 IMWSC 相比，IMSC 将氮氧化物排放与二氧化氮观测浓度之间的平均相关性提高了 25.0%，将氮氧化物排放与二氧化氮柱浓度之间的相关性提高了 111.3%。在 2021 年和 2020 年的典型月份中，各县的氮氧化物排放量变化比（σ平均值 = 5.1%）相似，这表明综合监测中心比综合监测中心（σ平均值 = 55.2%）的性能更稳定。此外，IMSC 所逆转的氮氧化物排放量与社会活动水平（即用电量）也表现出更好的一致性。我们还研究了临沂县级氮氧化物典型月度排放特征。由于 COVID-19 和污染控制，2021 年 4 月、7 月和 10 月的氮氧化物排放量低于 2020 年同期。这项研究为快速准确地估算污染物排放量提供了策略。

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引用次数: 0

Source apportionment of Volatile Organic Compounds (VOCs) in the South Coast Air Basin (SoCAB) During RECAP-CA RECAP-CA 期间南海岸空气盆地 (SoCAB) 挥发性有机化合物 (VOC) 的来源分配

IF 4.2 2区环境科学与生态学 Q2 ENVIRONMENTAL SCIENCES

Atmospheric Environment

Pub Date : 2024-09-28 DOI: 10.1016/j.atmosenv.2024.120847

Shenglun Wu , Christopher P. Alaimo , Peter G. Green , Thomas M. Young , Yusheng Zhao , Shang Liu , Toshihiro Kuwayama , Michael J. Kleeman

Ozone (O₃) concentrations in the South Coast Air Basin (SoCAB) surrounding Los Angeles remain at unhealthy levels despite multiple decades of control programs designed to reduce emissions of precursor Volatile Organic Compounds (VOCs). Here we report on comprehensive VOC measurements made at Redlands, which has the highest measured O₃ concentrations in SoCAB, as part of the Re-Evaluating the Chemistry of Air Pollutants in California (RECAP-CA) field campaign (July–October 2021). Positive matrix factorization (PMF) analysis was applied to identify nine VOC factors. A photochemical chamber model initialized by field measurements was configured with a tagging technique to quantify the VOC factor contributions to O₃ formation in Redlands. Biogenic VOCs (BVOCs) made the largest contribution (26.6%) to O₃ formation, followed by traffic VOCs (21.2%), volatile chemical products (VCPs) (19%), and plant decomposition (14.9%). High O₃ episodes were not driven by increased VOC emissions from any single source, but rather were associated with stagnation events that concentrated VOCs from all sources and high temperature days that enhanced O₃ formation efficiency. This implies that VOC controls optimized to reduce O₃ concentrations would look similar in both the NO_x-limited and VOC-limited regimes that can occur at Redlands. These results suggest that control strategies that reduce VOC and NO_x emissions from the on-road vehicle fleet, such as increasing electrification, may yield O₃ reductions on days in both the NO_x-limited and VOC-limited chemical regimes at Redlands.

尽管数十年来一直在实施旨在减少前体挥发性有机化合物 (VOC) 排放的控制计划，但洛杉矶周围的南海岸空气盆地 (SoCAB) 的臭氧 (O3) 浓度仍然处于不健康的水平。作为重新评估加利福尼亚空气污染物化学（RECAP-CA）实地考察活动（2021 年 7 月至 10 月）的一部分，我们在此报告了在雷德兰兹（SoCAB 中测得的臭氧浓度最高的地方）进行的挥发性有机化合物综合测量结果。应用正矩阵因式分解（PMF）分析确定了九个挥发性有机化合物因子。利用标记技术配置了由实地测量结果初始化的光化学室模型，以量化 VOC 因子对红地 O3 形成的贡献。生物源挥发性有机化合物（BVOCs）对臭氧形成的贡献最大（26.6%），其次是交通挥发性有机化合物（21.2%）、挥发性化学产品（VCPs）（19%）和植物分解（14.9%）。高臭氧事件并非由任何单一来源的挥发性有机化合物排放增加所导致，而是与集中了所有来源的挥发性有机化合物的停滞事件和提高了臭氧形成效率的高温天有关。这意味着，在雷德兰兹可能出现的氮氧化物受限和挥发性有机化合物受限的情况下，为降低臭氧浓度而优化的挥发性有机化合物控制措施看起来是相似的。这些结果表明，减少道路车辆排放的挥发性有机化合物和氮氧化物的控制策略（如提高电气化程度）可能会在雷德兰兹的氮氧化物受限和挥发性有机化合物受限化学环境下降低臭氧浓度。

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引用次数: 0

Human health impacts and indoor chemical reactions of VOCs from cleaning products and occupants 清洁产品和居住者产生的挥发性有机化合物对人体健康的影响和室内化学反应

IF 4.2 2区环境科学与生态学 Q2 ENVIRONMENTAL SCIENCES

Atmospheric Environment

Pub Date : 2024-09-27 DOI: 10.1016/j.atmosenv.2024.120846

Rachna Bhoonah , Maxence Mendez , Alice Maury-Micolier

Occupants and indoor activities are sources of volatile organic compounds (VOCs). We propose a framework to simulate the pollutant pathway using the INCA-Indoor© model and VOC emission rates to derive dynamic concentrations, and the USEtox model to evaluate health impacts in DALYs (Disability-Adjusted Life Years). The applicability of the framework is tested on a case study, and the effect of indoor chemical reactions on health impacts is assessed. In this case study, health impacts were of 0.3 μDALY/day without and 0.4 μDALY/day (13 s/day) with indoor air chemistry (+28 %) out of which 12 % were linked to occupant breath and skin emissions. Cleaning activities led to the highest impacts without chemical reactions (terpinolene, responsible for 0.14 μDALY/day), but indoor air chemistry led to high impacts linked to formaldehyde formation (0.18 μDALY/day). These reactions led to the formation of more formaldehyde, hence leading to 20% more impacts, in summer than in winter. Occupants’ contribution to CO₂ concentrations exceeded recommended limits under the given occupancy and ventilation scenario. Secondary organic aerosol (SOA) formation affected indoor particulate matter mass concentrations by up to a factor 1.2 and their number concentrations by up to a factor 25,000 in the presence of VOC emissions. Results of this study indicate that chemical reactions and SOA formation are important factors to consider in indoor air quality impact assessment. A larger number of activities and scenarios can be tested to improve the robustness of the conclusions, since, under different scenarios (for e.g. activities with lower emission rates) and with more complete toxicity data, these conclusions are likely to change.

居住者和室内活动是挥发性有机化合物 (VOC) 的来源。我们提出了一个模拟污染物路径的框架，利用 INCA-Indoor© 模型和挥发性有机化合物排放率得出动态浓度，并利用 USEtox 模型以 DALY（残疾调整生命年）为单位评估健康影响。该框架的适用性在一项案例研究中进行了测试，并评估了室内化学反应对健康影响的影响。在该案例研究中，无室内空气化学反应的健康影响为 0.3 μDALY/天，有室内空气化学反应的健康影响为 0.4 μDALY/天（13 秒/天）（+28%），其中 12% 与居住者的呼吸和皮肤排放有关。清洁活动导致的无化学反应影响最高（萜品烯，导致 0.14 μDALY/ 天），但室内空气化学导致的与甲醛形成有关的影响较高（0.18 μDALY/ 天）。这些反应导致了更多甲醛的形成，因此夏季的影响比冬季高出 20%。在特定的居住和通风情况下，居住者造成的二氧化碳浓度超过了建议限值。在有挥发性有机化合物排放的情况下，二次有机气溶胶（SOA）的形成对室内颗粒物质量浓度的影响高达 1.2 倍，对其数量浓度的影响高达 25,000 倍。研究结果表明，化学反应和 SOA 的形成是室内空气质量影响评估中需要考虑的重要因素。可以对更多的活动和情景进行测试，以提高结论的稳健性，因为在不同的情景下（例如排放率较低的活动），以及在毒性数据更加完整的情况下，这些结论很可能会发生变化。

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引用次数: 0