Atmospheric Pollution Research Articles

Salt Crystallization and Heritage Materials: Improving Durability by Understanding Porosity and Mineral Composition

ABSTRACT The current research examines the role of salt crystallization, a major factor in atmospheric pollution in coastal regions, on the degradation of biocalcarenite stones used in monuments in the Rabat-Salé area of Morocco. Focusing on Bouknadel and Bouskoura stones samples, the study conducted seven cycles of imbibition and desiccation with Na2SO4 and NaCl solutions (70 g/L and 100 g/L) to simulate marine aerosol effects. Additionally, capillary absorption was measured, and mass changes were documented after immersion in distilled water. X-ray diffraction and scanning electron microscopy were utilized to evaluate the chemical, mineralogical, and textural properties of the stones. The findings revealed that Bouknadel stone, despite its higher porosity (38 ± 9%), exhibited greater resistance to salt damage than Bouskoura stone (25 ± 5% porosity). This variation in response is attributed to differences in mineral composition, notably the presence of quartz in Bouknadel stone and sulfur in Bouskoura stone. Bouskoura stones faced significant deterioration, especially with Na2SO4, linked to the crystallization of thenardite. In contrast, Bouknadel stones maintained structural integrity despite halite crystal formation. These results underscore the importance of mineralogical composition and porosity in assessing stone susceptibility to salt degradation, offering critical insights for the conservation of cultural heritage in coastal ecosystems.

Source identification and characterization of water-insoluble single particulate matter in rainfall sequences

ABSTRACT Analysis of atmospheric pollutants in rainwater provides valuable information on the environmental impacts of both natural and anthropogenic pollution sources. Air pollution studies often show that particulate matter (PM) collection on filters is used for subsequent analysis. However, this approach can result in significant particle accumulation on filters and complicate their characterization by semi-quantitative analytical techniques. In this study, insoluble PM in sequentially collected rainwater samples was analyzed for particle size, morphology, and chemical composition. Scanning electron microscopy (SEM) coupled with energy-dispersive X-ray spectrometry (EDS) and a particle size analyzer were used for these analyses. By combining SEM–EDS data with particle size distribution analyses, chemical composition findings, and upper atmosphere back-orbit modeling, specific sources of insoluble particles in rainwater were identified. In addition, rainwater samples were analyzed for pH, electrical conductivity, and major anions and cations. The pH values varied from 6.19 to 7.04, while the electrical conductivity values varied from 5.35 to 83.53 μS/cm. Among the major ions, relatively high concentrations of Ca2+, SO42−, and NO3− were detected, while F−, Mg2+, Na+, and Cl− were observed in lower concentrations. The contributions of sea salt were evidenced by the presence of Cl− and Na+ ions.

Dilp2-Mediated Insulin Signaling Pathway Was Involved in O3-Induced Multigenerational Effects of Shortened Lifespan in Drosophila melanogasters.

As a long-standing atmospheric pollutant, ozone (O3) exerts enduring effects on biological health. However, experimental research on its impact on organism lifespan and generational effects is limited. This study exposed three generations of fruit flies (Drosophila melanogaster) to O3, revealing a shortened lifespan across generations. Specifically, after O3 exposure, the lifespan of the F2 generation was significantly reduced compared with F0 and F1 generations, indicating a cumulative multigenerational effect. Transcriptome analysis unveiled significant disruptions in metabolic pathways, notably the insulin signaling pathway. Subsequent qRT-PCR analysis showed elevated mRNA levels of insulin pathway-related genes (dilp2, dilp3, dilp5, InR, and TOR), alongside decreased expression levels of FOXO, 4E-BP, and Atg5 in flies exposed to O3. Notably, knocking down dilp2, rather than dilp3, dilp5, and InR, rescued the O3-induced lifespan shortening. Overall, O3 exposure triggered activation of the dilp2-mediated InR-FOXO/TOR-4E-BP-Atg5 signaling pathway, potentially contributing to shortened lifespan with cumulative effects. This study highlights the viability of employing fruit flies as a model to evaluate the multigenerational toxicity of environmental pollutants, particularly atmospheric pollutants.

Advancing Source Apportionment of Atmospheric Particles: Integrating Morphology, Size, and Chemistry Using Electron Microscopy Technology and Machine Learning.

To further reduce atmospheric particulate matter concentrations, there is a need for a more precise identification of their sources. The SEM-EDS technology (scanning electron microscopy and energy-dispersive X-ray spectroscopy) can provide high-resolution imaging and detailed compositional analysis for particles with relatively stable physical and chemical properties. This study introduces an advanced source apportionment pipeline (RX model) that uniquely combines computer-controlled scanning electron microscopy with computer vision and machine learning to trace particle sources by integrating single-particle morphology, size, and chemical information. In the evaluation using a virtual data set with known source contributions, the RX model demonstrated high accuracy, with average errors of 0.60% for particle number and 1.97% for mass contribution. Compared to the chemical mass balance model, the RX model's accuracy and stability improved by 75.6 and 73.4%, respectively, and proved effective in tracing Fe-containing particles in the atmosphere of a steel city in China. This study indicates that particle morphology can serve as an effective feature for determining its source. The findings highlight the potential of electron microscopy technology coupled with computer vision and machine learning techniques to enhance our understanding of atmospheric pollution sources, offering valuable insights for PM health risk assessment and evidence-based policy-making.

The evolution of food security in Japan-Based on an indicator evaluation system including climate change indicators.

As climate change intensifies, food security has received widespread attention. This study examines the development of Japan's food security index and its relationship with climate change. From these findings, a food security indicator system for Japan was established. The food security system has six dimensions: availability, nutrition, climate change, society, economics, and fertilizer. The factors affecting food security are complex and variable, and this paper adds the Fertilizer Security Index (FSI) to the previous studies. The overuse of fertilizers directly contributes to soil and atmospheric pollution, which can indirectly lead to issues of food quality insecurity. Including this factor within the food security system is fully justified. This enhances the precision of the food security index system to some degree. The results showed that Japan's overall food security index exhibited a slight downward trend from 0.113 in 1980 to 0.099 in 2022. Food security reached its lowest point of about 0.067 in 1993. In addition, all five indicators, except the fertilizer index, put pressure on the food security index. Due to the uncertainty inherent in climate change, specifically its ambiguous positive and negative impacts on food security, the Climate Change Security Index provides detailed evidence in this paper supporting whether climate change contributes to or undermines food security. Finally, the study put forward recommendations to ensure food security.

WOODY SPECIES CULTIVATED FOR ORNAMENTAL PURPOSES WITH INVASIVITY CAPACITIES IN OLTENIA, ROMANIA

Changes in climatic conditions influence the expansion on ever larger surfaces as well as the exacerbated development of populations of invasive species introduced in southern Romania initially for ornamental purposes. In the last decades, an increasing number of species that were cultivated for different purposes but also that accidentally entered Oltenia became successful invaders in different habitats. Many factors may contribute to the increased invasiveness of these species, including seed production, germination, and their relatively high growth rate. The impact of invasive species on native vegetation in a region can have different intensities, but they can increase with the accentuation of the drought and the aridification of the lands in the south of Oltenia, this may lead to the loss or irreversible degradation of habitats or species populations. In recent years in Oltenia, especially in the southern part, in the large hydrographic basins of the Danube, Jiu and Olt, the number of invasive species has increased considerably, their ability to spread and invasiveness being very high. Some of these species exert a high degree of aggression on wet, practical and forest habitats, influencing the structure and functionality of edifying phytocoenoses. Among the invasive species introduced for ornamental purposes in Oltenia, particularly important populations have developed: Acer negundo, Rhus typhina, Amorpha fruticosa, Ailanthus altissima, Eleagnus angustifolia, Fraxinus pensylvanica, F. americana, Parthenocissus inserta, P. quinquefolia, Robinia hispida. It should be noted that in recent years the species Albizia julibrissin was introduced for ornamental purposes in Romania, but also in Oltenia. This species is cultivated excessively, in gardens, green spaces, private yards and especially in the open spaces in front of private yards in most locations in Oltenia. Following the studies carried out regarding the invasive potential of this species, we can mention the fact that this species has a very high spreading power, quickly conquering new territories, each individual produces a very large number of seeds that have a very high germination power, is a species extremely resistant to drought, to various anthropogenic factors, including atmospheric pollution, to harmful mechanical factors, very high temperatures of over 400 during the summers in the south Oltenia, growing on the sides of roads, alleys, on several types of soil, including sandy. Around each individual, but also at distances between 2-80 m from it, vigorous saplings were identified, with increased vitality and accelerated growth, being able to reach up to 30-40 cm in height in one year of vegetation. Thus, we can specify that this species can be considered a new invasive species for Romania.

Carbon Dioxide Recycling into Fuels and Valuable Chemicals

The present review proposes an approach for remediation of atmosphere pollution by carbon dioxide. The global economic growth nowadays requires extensive energy consumption. Energy is produced traditionally by combustion of carbon containing fuels, resulting in the release of large amounts of carbon dioxide in the atmosphere. These emissions of released CO2 lead to the greenhouse effect on the atmosphere with subsequent impact on the global climate. Remediation of this harmful effect requires reduction in CO2 emissions. In addition to improving the efficiency of energy consumption, this reduction can be also accomplished by the recycling of carbon dioxide into fuels and useful commodities. This conversion of CO2 into fuels and commercial products leads to multiple benefits such as reduction in carbon emissions and greenhouse gases, production of value-added goods, thus reducing oil consumption and associated pollutions of the environment. This review summarizes the efforts to remove, or at least to remediate, the release of carbon dioxide in the atmosphere by its conversion to value-added products prior to discharging. Some of these products are urea, methanol, formic acid, some polymers of practical importance, light hydrocarbons and methane. The recent achievements in chemical catalysis, electrochemistry, bioelectrochemistry and photocatalysis are considered. Discussion on the feasibility of the considered methods compared to the traditional technologies is made. It is concluded that although production of value-added chemicals by carbon dioxide recycling is not yet competitive, it seems promising in the future when its economic feasibility will become a reality.

Identification of particulate matter (PM10 and PM2.5) sources using bivariate polar plots and k-means clustering in a South American megacity: Metropolitan Area of Lima-Callao, Peru.

The identification of different air pollution sources is essential to effectively control atmospheric pollution, particularly in megacities of emerging countries with rapid economic development, such as the Metropolitan Area of Lima-Callao (MALC). The objective of this research was to identify the main sources of particulate matter pollution by applying bivariate polar plots and the k-means clustering algorithm. These statistical techniques were applied to hourly in situ data of four variables collected over a 5-year period (2015-2019) by the Automatic Air Quality Monitoring Network of the MALC: wind direction, wind speed, PM10, and PM2.5 concentrations. Average PM10 concentrations ranged from 34μgm-3 (CDM station) to 126.7μgm-3 (VMT station), while average PM2.5 concentrations ranged from 16.8μgm-3 (CDM station) to 41.2μgm-3 (ATE station). The diurnal variation of PM presented two peaks, one in the morning (from 0800 to 1000h) and the other at night (from 1900 to 2300h), with the highest concentrations of PM10 recorded at the ATE (0800h: 155.8μgm-3) and VMT (2100h: 154.6μgm-3) stations, and PM2.5 at the ATE station (0800h: 60.3μgm-3 and 2300h: 37.5μgm-3). The results showed that the contributions of PM10 are directly related to emissions from industrial activities, automotive fleet, construction, demolition, wind erosion, and the suspension and resuspension of particulates from unpaved roads. Meanwhile, high concentrations of PM2.5 are mainly attributed to vehicle exhaust emissions, industrial emissions, secondary particulate formation, and drag by the action of the winds. The major source of particulate matter contamination is the vehicle fleet, and within this, automobiles, station wagons, combi vans, and 2 and 3-wheel motorcycles are those that have the greatest contribution. These results were supported by non-parametric statistical tests such as Kruskal-Wallis and Mann-Whitney U and validated by the conditional bivariate probability function. The findings of this work may help to implement pollution prevention and control strategies in the future within this South American megacity.

Changes in dust concentration in a gas-dust cloud during blasting in an iron ore pit

In open-pit extraction of minerals emit large amounts of harmful dust fractions and gas into the atmosphere. This leads to atmospheric pollution in open pit and sanitary protection zones. The largest dust emissions are observed during blasting operations in open pits. This is especially the cases when unfavorable meteorological conditions occur, means of dust sup-pression are not sufficiently effective, blasting technology was violated. Dust particles are known to be able to propagate long distances from the source of the explosion. Dust fractions up to 10 µm diameter are the most dangerous, as they are the main risk factor for the devel-opment of chronic respiratory diseases. In particular, according to European standards, the average daily concentration of dust particles with a diameter between 2.5 and 10 µm should not exceed 0.05 mg/m3. The paper estimates mass concentrations of dust fractions in the gas-dust cloud at the dynamic stage of its formation after a mass explosion in an iron ore open pit. The following assumptions were made in the calculations: no influence of the temperature factor (ejected air flows); dust particles are spherical; flow of dust fractions by the gas flow follows the Stokes law. The ranges of variation of ascent height and mass concentrations of dust fractions at the dynamic stage of gas-dust cloud formation are established. In particular, the lift height of the dust fraction is directly proportional to the value of the dynamic impulse. The differ-ence in mass concentrations of dust fractions in the gas-dust cloud is due to the physical and mechanical properties of rocks destroyed by boreholes explosive substance charge. When de-termining the mass concentrations of dust fractions, the results of experimental studies were used, which were carried out in the open pit of Ingulec Mining and Processing Combine. The graphical dependence of average mass concentrations of dust fractions depending on the height of their ascent at the dynamic stage of gas-dust cloud formation is presented, the re-gression equation in the form of a degree function is obtained. The results of calculations have shown that the greatest intensity of mass concentration increase in the gas-dust cloud at the dynamic stage of its formation is characteristic of dust fractions with diameter up to 31 μm. The intensity of growth of mass concentrations of larger dust fractions decreases markedly.

Multilayer temperature inversion structures and their potential impact on atmospheric pollution in northwest China

Multilayer temperature inversion structures and their potential impact on atmospheric pollution in northwest China

Unveiling the seasonal transport and exposure risks of atmospheric microplastics in the southern area of the Yangtze River Delta, China.

This study investigates the prevalence and impacts of suspended atmospheric microplastics (SAMPs) in the coastal metropolitan city of Ningbo in the Yangtze River Delta Region, China. The sampling was conducted at both urban centre and urban-rural fringe areas, near the coast but distant from large urban populations. SAMP abundance ranged from 0.017 to 0.430 items m-³, with an average of 0.145±0.09 items m⁻³. The urban centre exhibited approximately 70% more SAMPs than the urban-rural fringe, highlighting the influence of population density and human activity on microplastic pollution. Fibres dominated SAMP composition at both sites, while urban samples featured a greater variety of microplastic forms, such as fragments, beads, and films. Rayon and Polyethylene terephthalate were the predominant polymers, which were found to be directly related to local industrial activities. SAMPs ranged in size from 20μm to 4984.4μm, with over 60% smaller than 1000μm. Seasonal variation followed a winter>autumn>spring>summer pattern. Correlation and principal component analyses identified atmospheric temperature, pressure, wind speed, and rainfall as key factors influencing SAMP abundance. Notably, backward trajectory analysis showed that oceanic air masses carried significantly fewer SAMPs compared to terrestrial air, diluting concentrations in coastal regions. Annually, an estimated 4.67×101³ microplastics are suspended over Ningbo. This is the first comprehensive study of SAMP pollution in this region, revealing interactions between local sources, environmental variations, air mass dynamics, and exposure. The findings underscore the need for targeted strategies to mitigate atmospheric microplastic pollution in coastal urban environments.

The influence of road vehicle tyre wear on microplastics in a high-traffic university for sustainable transportation.

Road-associated microplastics, originating from tire wear and fragmented litter, are significant contributors to microplastic pollution. This study examines the characteristics of these particles within a university, focusing on their size, shape, color, and polymer composition. Suspended microplastics were collected using portable active samplers for PM10 and results have shown that PM10 concentrations peaked on Thursdays and declined, reaching their lowest levels on Sundays, with overall weekend measurements indicating reduced concentrations compared to weekdays. Importantly, the presence of microplastics correlated with increased PM10 levels. These findings highlighted a dominance of irregularly fragmented black microplastics, primarily composed of polyethylene, polypropylene, and polybutadiene, influenced mainly by vehicular movement. Additionally, metal contaminants such as aluminum, iron, and zinc were identified through SEM-EDX analysis of selected microplastics, particularly concentrated at the university's main entrance, the area with the highest traffic. This research enhances understanding of atmospheric microplastic pollution in university environments with heavy vehicle traffic and supports efforts to promote sustainable transportation and climate-friendly initiatives.

Transforming sludge into energy: impact of blend percentage on energy recovery potential and environmental benefits of co-combustion of wastewater sludge and coal in Brazil.

Proper waste management and sustainable energy production are crucial for human development. For this purpose, this study evaluates the impact of blending percentage on energy recovery potential and environmental benefits of co-combustion of wastewater sludge and Brazilian low-rank coal. The sludge and coal were characterised in terms of their potential as fuel and co-combustion tests were carried out in a pilot-scale bubbling fluidised bed focused on the influence of the percentage of sludge mixture on the behaviour of co-combustion with coal in terms of flue gas composition and fluidised bed temperature stability. Sludge has a higher heating value (16.276MJ/kg) than coal (15.486MJ/kg) and a higher fuel ratio (8.48 vs. 0.21). The O2 and CO2 levels found in the co-combustion tests, together with a very low CO concentration, indicate good combustion. However, the NOx emission was considerable, varying from 825.2±94.5 to 1,320.5±33.8mg/m3 (O2ref=7%), pointing to the need for actions to reduce atmospheric pollution. Coal had higher ash content (52.64% vs. 25.00% d.b.). The temperatures in the bed region and in the combustion region showed similar behaviour for all the fuels. The addition of sewage sludge to mineral coal reduced the ash content without increasing the ash fusibility risk in the combustion temperature range evaluated. These findings suggest that sludge addition in co-combustion with coal offers promising results for both energy production and environmental sustainability.

Change in aerosol optical depth in Chinese urban agglomerations during the early phase of dual-carbon actions

Dual-carbon policies were implemented by Chinese government to mitigate climate warming; however, changes in aerosol optical depth (AOD) during early phases of these actions (2020-2022) remain unclear. Thus, AOD variations during this period were investigated compared to the baseline (2015-2019 mean) across seven urban agglomerations (UAs) using multi-source data. Significant temporal variations in AOD anomalies (ΔAOD) were observed at annual and seasonal scales, with varying magnitudes. On average, AOD decrease by -0.210, -0.225, -0.180, and -0.038 in Beijing-Tianjin-Hebei (BTH), Yangtze River Delta (YRD), Guanzhong Plain (GZP), and Liaozhongnan (LZN), respectively. In contrast, increases of 0.041 and 0.057 were observed in Pearl River Delta (PRD) and Tianshan Mountains northern foothills (TSBP), while Lhasa metropolitan area (LS) remain stable (0.0001). In 2021, the most significant decrease in AOD was recorded in YRD, whereas the greatest declines in other urban areas were noted in 2022. The largest ΔAOD in LZN, BTH, and YRD occurred in autumn, while the peak ΔAOD in GZP was observed in spring. In contrast, the highest ΔAOD in PRD, TSBP, and LS occurred in summer. These temporal variations in ΔAOD can be attributed to dual-carbon policies, natural and meteorological anomalies, along with the impacts of stringent lockdown policies and abrupt dust events. Path analysis indicated that the effects of various drivers on ΔAOD were interconnected. When interactions among these factors were considered, their influences on ΔAOD were found to be either amplified or altered, highlighting the importance of accounting for interactions within the human-nature-meteorological system in formulation of atmospheric pollution policies. These findings contribute to a deeper understanding of ΔAOD variation mechanisms and provide valuable insights for the development of air pollution reduction strategies at the UA scale.

Regulating (ecosystem) services of an urban natural area: A case study in the State of Rio de Janeiro, Brazil.

Peri-urban conserved natural or semi-natural areas provide several ecosystem services and assist in reducing air pollution in cities. The aim of this study is to assess the contribution to the improvement of air quality of a small area (<1km2) adjacent to a city in the Metropolitan Region of Rio de Janeiro (Brazil), which is seriously affected by vehicular and industrial emissions of pollutants. Hydrocarbon (HC) and carbonyl compounds (CC) levels were determined, by employing TO-15 and TO-11A US EPA Methods, respectively, in both the urban and green areas. The results showed that the concentrations of anthropogenic HC were approximately 1.7-2.1 times higher in the urban area which confirms that the natural park assists in the dispersion and reduction of pollutants. In the case of the CC compounds, for samples that were collected in the morning, the total mean and median values were 1.3-1.6 times higher in the urbanized zone, while during the afternoon the green area showed values that were 1.5-1.9 times higher. These results suggest that in the green area, the emission or formation of CC compounds through photochemical processes is significant, particularly in the afternoon. Anyway, the ozone forming potential was found to be lower within the natural park in both periods, which confirms the positive role played by conserved natural areas outside or surrounding extensive metropolitan areas in the reduction of atmospheric pollution, in spite of the negative impact of anthropogenic emissions.

Nitrogen Dioxide Detection with Ambipolar Silicon Nanowire Transistor Sensors.

Si nanowire transistors are ideal for the sensitive detection of atmospheric species due to their enhanced sensitivity to changes in the electrostatic potential at the channel surface. In this study, we present unique ambipolar Si junctionless nanowire transistors (Si-JNTs) that incorporate both n- and p-type conduction within a single device. These transistors enable scalable detection of nitrogen dioxide (NO2), a critical atmospheric oxidative pollutant, across a broad concentration range, from high levels (25-50 ppm) to low levels (250 ppb-2 ppm). Acting as an electron acceptor, NO2 generates holes and functions as a pseudodopant for Si-JNTs, altering the conductance and other device parameters. Consequently, ambipolar Si-JNTs exhibit a dual response at room temperature, reacting on both p- and n-conduction channels when exposed to gaseous NO2, thereby offering a larger parameter space compared to a unipolar device. Key characteristics of the Si-JNTs, including on-current (Ion), threshold voltage (Vth) and mobility (μ), were observed to dynamically change on both the p- and n-channels when exposed to NO2. The p-conduction channel showed superior performance across all parameters when compared to the device's n-channel. For example, within the NO2 concentration range of 250 ppb to 2 ppm, the p-channel achieved a responsivity of 37%, significantly surpassing the n-channel's 12.5%. Additionally, the simultaneous evolution of multiple parameters in this dual response space enhances the selectivity of Si-JNTs toward NO2 and improves their ability to distinguish between different pollutant gases, such as NO2, ammonia, sulfur dioxide and methane.

Atmospheric pollution affects the morphoanatomical and physiological responses of plants in urban Atlantic Forest remnants.

The Metropolitan Area of São Paulo (MASP) in southern Brazil is impacted by high ozone levels posing significant threats to its urban forests and the Atlantic Forest remnants. These green areas, covering 540 km2 and constituting 30% of MASP's territory, necessitate an urgent assessment of air pollution impacts on their flora. Our study investigates the effects of atmospheric pollution on the morphoanatomical and physiological responses of four native tree species (Alchornea sidifolia, Casearia sylvestris, Guarea macrophylla, and Machaerium nyctitans) across two Atlantic Forest remnants in MASP. We examined visual and morphoanatomical changes in leaves, gas exchange, photosynthetic pigments, and plant volatile organic compounds to identify markers for biomonitoring urban environments. Our results reveal that MASP vegetation is adversely affected by tropospheric ozone. Species with porous mesophyll structures, such as M. nyctitans and G. macrophylla, exhibited greater visual and structural damage. In contrast, species with compact mesophyll, such as A. sidifolia and C. sylvestris, demonstrated higher tolerance. This suggests that anatomical architecture critically influences species' responses to atmospheric pollutants, such as tropospheric ozone. Additionally, we propose that ozone influx occurs through both stomatal pathways and as a result of direct and indirect injuries to the plant tissues. Additionally, our study identifies non-visual markers, including anatomical and physiological parameters and plant volatile organic compounds (e.g., presence of salicylates), as effective tools for monitoring plant species in urban environments. These insights highlight key anatomical and metabolic markers that help distinguish ozone-tolerant species from sensitive species, providing valuable information for monitoring air pollution in urban forests.

Оцінка якості атмосферного повітря Житомира за показниками ушкодженості пилку Spiraea x vanhouttei

An assessment of the state of Spiraea x vanhouttei pollen in the green areas of Zhytomyr under the influence of various factors of urbotechnogenic origin was carried out. A species of perennial plants of the shrub layer was selected for bioindicative studies. The generative part of these plant species is exposed to the main components of air pollution for a long time, as is the human respiratory system. Assessment of the state of atmospheric air in the surface layer is important for determining potential consequences for the ecosystem and assessing the risk to public health. Atmospheric air pollution by emissions of pollutants from industrial enterprises and motor vehicles is one of the main environmental problems of Zhytomyr and the region. Although in general, according to the data of the CGO named after B. Sreznevskyi, Zhytomyr belongs to the cities with a low level of atmospheric air pollution. It occupies the 23rd position among other cities of Ukraine. The article describes the characteristics of the main components of air pollution and their sources. To monitor the state of the gametophyte S. x vanhouttei, 6 locations were selected in different districts of the city, which differ in terms of anthropogenic load and the presence of green spaces. The sensitivity of pollen was studied by qualitative (fertility) and quantitative indicators. In most of the studied territories, plants have retained a high reproductive potential. A significant loss (by 2.1–2.25 times) of pollen fertility was noted only in plants in the territory with increased influence of emissions from mobile sources. The depressive effect of exogenous factors is more evidenced by the variability of morphometric characteristics. In particular, the production of morphologically diverse pollen grains and the reduction of their average size. In particular, the production of a larger share of morphologically diverse pollen grains and a decrease in their average size was noted. This is also due mainly to the impact of emissions from motor vehicles, as this is the area where the city’s largest transport hubs are located – the railway station and the central bus station. Thus, the conclusions of the Central Geophysical Observatory named after B. Sreznevsky regarding the dominant influence of mobile sources in the total amount of pollutants in the urban ecosystem of Zhytomyr. The established manifestations of the sensitivity of S. vanhouttei pollen to a complex of exogenous factors of the growing environment confirm the prospects of its use as a medium-resistant species for bioindicative assessment of the state of the environment.

Effects of atmospheric pollution and vegetation on nitrogen and phosphorus content in agri-forest watersheds under climate

Effects of atmospheric pollution and vegetation on nitrogen and phosphorus content in agri-forest watersheds under climate

Determining an Optimal Combination of Meteorological Factors to Reduce the Intensity of Atmospheric Pollution During Prescribed Straw Burning

Currently, large-scale burning is an important straw disposal method in most developing countries. To execute prescribed burning while mitigating air pollution, it is crucial to explore the maximum possible range of meteorological changes. This study conducted a three-year monitoring program in Changchun, a core agricultural area in Northeast China severely affected by straw burning. The data included ground-level pollutant monitoring, ground-based polarized LiDAR observations, and ground meteorological factors such as planetary boundary layer height (PBLH), relative humidity (RH), and wind speed (WS). Using response surface methodology (RSM), this study analyzed key weather parameters to predict the optimal range for emission reduction effects. The results revealed that PM2.5 was the primary pollutant during the study period, particularly in the lower atmosphere from March to April, with PM2.5 rising sharply in April due to the exponential increase in fire points. Furthermore, during this phase, the average WS and PBLH increased, whereas the RH decreased. Univariate analysis confirmed that these three factors significantly impacted the PM2.5 concentration. The RSM relevance prediction model (MET-PM2.5) established a correlation equation between meteorological factors and PM2.5 levels and identified the optimal combination of meteorological indices: WS (3.00–5.03 m/s), RH (30.00–38.30%), and PBLH (0.90–1.45 km). Notably, RH (33.1%) emerged as the most significant influencing factor, while the PM2.5 value remained below 75 μg/m3 when all weather indicators varied by less than 20%. In conclusion, these findings could provide valuable meteorological screening schemes to improve planned agricultural residue burning policies, with the aim of minimizing pollution from such activities.