Reduce Air Pollution Research Articles

Towards Green and Low-Carbon Transformation via Optimized Polygeneration System: A Case Study of the Iron and Steel Industry

Polygeneration systems have significant potential for energy conservation and emission reduction and can effectively promote green and low-carbon development in energy-intensive industries, such as the iron and steel industry. However, its application faces the difficulty in technology selection under multiple objectives simultaneously, which is to determine the technology portfolio to achieve the synergy of energy conservation goals and air pollutant emission reduction goals, as well as ensure the economic benefits of the enterprises. This study investigated a case polygeneration system where the iron and steel plant are the core with four polygeneration paths and twenty polygeneration technologies. A multi-objective optimization model is developed to select the optimal technology combination of each polygeneration path under energy conservation, emission reduction, and cost control objectives, which is solved by the non-dominated sorting genetic algorithm-II (NSGA-II). The optimal results can reach significant energy conservation and emission reduction effects while obtaining economic benefits. However, synergistic and conflicting relationships among the objectives exist in both scales of iron and steel plants. The final decision scheme can achieve the mitigations equivalent to 15.9–27.1% and 16.3–42.6% of the energy consumption and air pollutant emissions of the steel enterprises with annual production of 3 Mt/a and 9 Mt/a, respectively. There are thirteen and twelve technologies that are selected as the final decision scheme in the polygeneration system in these two case enterprises. These findings demonstrate the significant roles the polygeneration system plays and provide critical insights and methodology in the technical selection of the polygeneration system.

Causal effects of air pollutants on lung function and chronic respiratory diseases: a Mendelian randomization study.

Our study aims to clarify the causality between air pollutants and lung function, chronic respiratory diseases, and the potential mediating effects of inflammatory proteins. We employed Mendelian Randomization (MR) analysis with comprehensive instrumental variables screening criteria to investigate the effects of air pollutants on lung function and chronic lung diseases. Our study incorporated genetic instruments for air pollutants, ensuring F-statistics above 20.86. A total of 18 MR analyses were conducted using the inverse-variance weighted approach, along with heterogeneity and pleiotropy tests to validate the results. Mediated MR analysis was utilized to evaluate the inflammatory proteins mediating the effects of air pollutants. MR analysis demonstrated significant causal interactions of particulate matter 2.5 (PM2.5), PM10, and Nitrogen dioxide (NO2) with lung function decline. Specifically, PM10 negatively affected forced expiratory volume in one second (FEV1) (OR: 0.934, 95% CI: 0.904-0.965, p = 4.27 × 10-5), forced vital capacity (FVC) (OR: 0.941, 95% CI: 0.910-0.972, p = 2.86 × 10-4), and FEV1/FVC (OR: 0.965, 95% CI: 0.934-0.998, p = 0.036). PM2.5 and NO2 were identified as potential risk factors for impairing FEV1 (OR: 0.936, 95% CI: 0.879-0.998, p = 0.042) and FEV1/FVC (OR: 0.943, 95% CI: 0.896-0.992, p = 0.024), respectively. For chronic respiratory diseases, PM2.5 and NO2 were associated with increased COPD incidence (OR: 1.273, 95% CI: 1.053-1.541, p = 0.013 for PM2.5; OR: 1.357, 95% CI: 1.165-1.581, p = 8.74 × 10-5 for NO2). Sensitivity analyses confirmed the robustness of these findings, with no significant heterogeneity or horizontal pleiotropy detected. Our study ascertained the causal correlations of air pollutants with lung function and COPD, emphasizing the importance of reducing air pollution. Interleukin-17A mediates the reduction of FEV1 and FVC by PM10, revealing potential therapeutic targets.

The Effect of Using Absorbent Carbon on Air Exposed to Air Fresheners on The Histology of The Cornea of The White Rat (Rattus Novergicus)

Air freshener contain hazardous chemical such as formaldehyde. Absorbent carbon is used as an adsorbent to reduce air pollution. The goal of this research is to know the use of absorbent carbon to cornea histology on Rattus novergicus that was induced with air freshener. This research was an experimental study with a post-test only control group. The subjects were 28 one-month old male Rattus novergicus Wistar strains divide into 4 groups: Control (K), air freshener (P1), absorbent carbon (P2) and air freshener plus absorbent carbon (P3).The treatment was performed 8 hours/day for 35 days. Data of anterior epithelial thickness were analyzed by One Way Anova test. Data of the overall thickness of the corneal layer and keratocyte number were analyzed by Kruskal Wallis test. The overall thickness of the corneal layer and anterior epithelial thickness showed that there were not significant difference between subject groups (p>0,05). Anterior epithelial thickness showed that there were not significant difference between subject groups (p>0,05). Keratocyte number showed significant difference between subject groups (p<0,05), Mann Whitney test for Keratocyte number showed results P1>P3>K>P2 Absorbent carbon gives postitive effect to reduce cornea damage on Rattus novergicus that induced by air freshener.

Digital finance policy and the challenge of air pollution in China

This study investigates the influence of digital finance tools on air quality in China from 1990 to 2020 using the cross-sectional augmented autoregressive distributed lag approach. The findings underscore the critical role of digital finance, especially internet banking, in reducing air pollution levels. The increased adoption of internet banking is linked to lower vehicular emissions and more efficient financial operations, aiding environmental preservation. Similarly, ATM banking is found to negatively correlate with air pollution, though to a lesser extent. In contrast, coal consumption, urban population growth, and inflation are positively associated with air pollution, highlighting the necessity for sustainable urban planning and energy transition policies. To combat air pollution, it is essential to utilize digital finance tools, broaden digitalization across various sectors, and employ AI and big data for precise interventions. Supporting green financial tools can help fund renewable energy projects, speeding up China’s shift to a low-carbon economy and mitigating the harmful effects of air pollution.

A real-time assessment of hazardous atmospheric pollutants across cities in China and India

China and India are two of the fastest-growing developing economies covering about 35 % of the world’s population. Due to the extensive prevalence of air pollution across cities in China and India, contemporary assessment of atmospheric pollution through real-time and remote sensing observations is inadequate. The study aims to determine the spatial distribution and temporal variation of hazardous atmospheric pollutants across cities in China (Shanghai, Nanjing, Jinan, Zhengzhou and Beijing) and India (Kolkata, Asansol, Patna, Kanpur and Delhi). Ground observation data on CO, O3, PM2.5, PM10, NO2 and SO2 along with remote sensing data on AOD, CO, O3, BC, NO2, SO2 and dust surface mass concentrations are used to assess atmospheric pollution. This study examines daily, zonal and longitudinal pollutant distributions using Sentinel-5 P data and surface mass concentrations over the vertical column evaluated from NASA satellite data. The Mann-Kendall test and relative change methods have been implemented to assess pollutant trends while Sen’s Slope identifies the magnitude of change. The similarity test and data validation methods including NRMSE, PC and MBias have been employed to ensure consistency in analysing annual trends for each air pollutant in the datasets. Additionally, multiple correlation matrix analysis has been used to examine the associations among different pollutants from both datasets based on their annual averages. Remote sensing data reveals that eastern China and north-eastern India have the highest aerosol, BC, CO, NO2 and SO2 while western China and southern India lowest. Dust peaks in the west while O3 levels are highest in the northern part of China and India. Ground observation data indicates that Chinese cities have higher annual mean SO2 and O3 concentrations with yearly declines in PM2.5, PM10, NO2, SO2 and CO notably SO2. Indian cities witnessed overall increases in PM2.5, PM10, NO2 and SO2 from 2012 to 2019 with a slight decline in 2020 followed by a resurgence in 2023. The findings provide insights for implementing regional policy measures to reduce air pollution based on changes in pollutant behaviour. The study suggests that addressing atmospheric pollutants, particularly NO2, CO, PM2.5, PM10, and SO2 requires a comprehensive environmental policy framework involving central and state governments and enforcing stringent environmental protection laws.

Study on rapid policy-based strategic environmental assessment-taking China's regional development policy of Zhejiang Pilot Free Trade Zone as an example

Strategic Environmental Assessment(SEA) is acknowledged to be an important decision support tool. SEA concerns potential environmental impacts of decisions made by policy, plan and programs. At present, policy-based SEA is still in the exploratory stage in China. The development of policy-based SEA is extremely slow due to institutional and technical difficulties. In practice, the time from policy proposals to policy implementation is relatively short. So the corresponding policy-based SEA should reflect the characteristics of rapidity, centre on the seriously negative impact that may be caused policy implementation, and provide early and initial warnings.A simple and rapid framework was designed for policy-based SEA in this study. The framework includes four parts, namely, policy analysis, eco-environmental impact identification, eco-environmental sensitivity assessment, policy recommendations. Following this framework, regional development policy of Zhejiang Pilot Free Trade Zone (FTZ) was assessed. Results reveal that: 1)seriously negative environment impacts may arise from petroleum refining and chemical industry, oil and gas storage and transportation, iron ore transportation, liquid bulk commodities transportation. 2) Central Daishan area, Shengsi archipelago, Taohua Island, Liuheng island in Zhejiang FTZ is relatively of high eco-sensitivity, thus the fore-mentioned activities should be environmentally friendly or restricted in these areas. 3)In the future, continuous efforts should be made to promote sealing and automation of petroleum refining, chemical industry. Green petrochemical manufacturing technology utilization is recommended to reduce pollution from the source. Further, accelerating the construction of transportation pipelines is suggested in order to reduce air pollutants emissions caused by vehicle transportation activities. Fishery stock enhancement and releasing is recommended to counteract negative impact on fishery caused by iron and liquid bulk commodity marine transportation.

Air Pollution and Parkinson Disease in a Population-Based Study

The role of air pollution in risk and progression of Parkinson disease (PD) is unclear. To assess whether air pollution is associated with increased risk of PD and clinical characteristics of PD. This population-based case-control study included patients with PD and matched controls from the Rochester Epidemiology Project from 1998 to 2015. Data were analyzed from January to June 2024. Mean annual exposure to particulate matter with a diameter of 2.5 µm or less (PM2.5) from 1998 to 2015 and mean annual exposure to nitrogen dioxide (NO2) from 2000 to 2014. Outcomes of interest were PD risk, all-cause mortality, presence of tremor-predominant vs akinetic rigid PD, and development of dyskinesia. Models were adjusted for age, sex, race and ethnicity, year of index, and urban vs rural residence. A total of 346 patients with PD (median [IQR] age 72 [65-80] years; 216 [62.4%] male) were identified and matched on age and sex with 4813 controls (median [IQR] age, 72 [65-79] years, 2946 [61.2%] male). Greater PM2.5 exposure was associated with increased PD risk, and this risk was greatest after restricting to populations within metropolitan cores (odds ratio [OR], 1.23; 95% CI, 1.11-1.35) for the top quintile of PM2.5 exposure compared with the bottom quintile. Greater NO2 exposure was also associated with increased PD risk when comparing the top quintile with the bottom quintile (OR, 1.13; 95% CI, 1.07-1.19). Air pollution was associated with a 36% increased risk of akinetic rigid presentation (OR per each 1-μg/m3 increase in PM2.5, 1.36; 95% CI, 1.02-1.80). In analyses among patients with PD only, higher PM2.5 exposure was associated with greater risk for developing dyskinesia (HR per 1-μg/m3 increase in PM2.5, 1.42; 95% CI, 1.17-1.73), as was increased NO2 exposure (HR per 1 μg/m3 increase in NO2, 1.13; 95% CI, 1.06-1.19). There was no association between PM2.5 and all-cause mortality among patients with PD. In this case-control study of air pollution and PD, higher levels of PM2.5 and NO2 exposure were associated with increased risk of PD; also, higher levels of PM2.5 exposure were associated with increased risk of developing akinetic rigid PD and dyskinesia compared with patients with PD exposed to lower levels. These findings suggest that reducing air pollution may reduce risk of PD, modify the PD phenotype, and reduce risk of dyskinesia.

Ecosystem Services and Public Perception of Green Infrastructure from the Perspective of Urban Parks: A Case Study of Luoyang City, China

As one form of urban green infrastructure, city parks provide essential ecosystem services and serve as a vital link connecting citizens with natural ecosystems. The public, as the primary beneficiaries of urban park ecosystem services, plays a crucial role in guiding the improvement and development trends of urban park planning. Most existing studies assess the comprehensive value of green spaces from a macro scale, with few focusing on the cultural and regulatory ecosystem services of urban parks and public perception of these services at the park level. This study targets 11 typical urban parks in Luoyang City, collecting 771 samples through field mapping and surveys. It analyzes users’ socio-demographic characteristics, perception abilities, usage preferences, and service satisfaction, linking these subjective factors with objective elements of the park environment, such as fitness and recreational facilities. The results indicate that respondents with knowledge of ecosystem services are better able to evaluate and understand services such as air pollution reduction and noise reduction in parks, while those without such knowledge tend to focus more on services that they can intuitively perceive, such as biodiversity conservation and microclimate regulation. Additionally, the middle-income group exhibits a higher level of awareness of park ecosystem services, which depends on their active social participation. The findings of this study suggest that enhancing public understanding of ecosystem services through environmental education is key to improving the quality of urban ecosystems.

Health equity and synergistic abatement strategies of carbon dioxide and air pollutant emissions reduction in China’s eastern coastal area

Abstract Quantifying regional health disparities linked to air pollution is essential for enhancing air quality and attaining carbon neutrality objectives. Nonetheless, the efficacy of proactive policies in ensuring equitable health protection in China’s Eastern Coastal Area (ECA) remains uncertain. Here, we employed an integrated assessment model to assess the combined reduction of carbon dioxide (CO2) and atmospheric pollutants and their health repercussions in the ECA of China. Our findings reveal that 273 000 premature deaths are attributable to air pollution in 2060 in the ECA in the absence of mitigation policies. Conversely, carbon reduction policies are poised to curtail 80% of CO2 emissions, alongside reductions of 76% for NOx, 79% for SO2, 80% for PM2.5, 72% for VOCs, and 66% for NH3 emissions. Air pollution control policies could mitigate premature deaths by 19 600, while carbon reduction policies could potentially lower them by 50 800. The health inequality coefficient among provinces stands at 0.19, primarily attributable to significantly higher mortality rates in Hebei and Shandong. These findings yield valuable insights for crafting synergistic abatement strategies in similarly imbalanced developmental regions grappling with comparable environmental challenges.

Air pollution: a latent key driving force of dementia

Many researchers have studied the role of air pollutants on cognitive function, changes in brain structure, and occurrence of dementia. Due to the wide range of studies and often contradictory results, the present systematic review was conducted to try and clarify the relationship between air pollutants and dementia. To identify studies for this review, a systematic search was conducted in Scopus, PubMed, and Web of Science databases (without historical restrictions) until May 22, 2023. The PECO statement was created to clarify the research question, and articles that did not meet the criteria of this statement were excluded. In this review, animal studies, laboratory studies, books, review articles, conference papers and letters to the editors were avoided. Also, studies focused on the effect of air pollutants on cellular and biochemical changes (without investigating dementia) were also excluded. A quality assessment was done according to the type of design of each article, using the checklist developed by the Joanna Briggs Institute (JBI). Finally, selected studies were reviewed and discussed in terms of Alzheimer's dementia and non-Alzheimer's dementia. We identified 14,924 articles through a systematic search in databases, and after comprehensive reviews, 53 articles were found to be eligible for inclusion in the current systematic review. The results showed that chronic exposure to higher levels of air pollutants was associated with adverse effects on cognitive abilities and the presence of dementia. Studies strongly supported the negative effects of PM2.5 and then NO2 on the brain and the development of neurodegenerative disorders in old age. Because the onset of brain structural changes due to dementia begins decades before the onset of disease symptoms, and that exposure to air pollution is considered a modifiable risk factor, taking preventive measures to reduce air pollution and introducing behavioral interventions to reduce people's exposure to pollutants is advisable.

Co-Benefits of Antimicrobial Resistance Mitigation from China’s PM2.5 Air Pollution Reduction Between 2014–2020

The One Health concept acknowledges the importance of multiple dimensions in controlling antimicrobial resistance (AMR). However, our understanding of how anthropological, socioeconomic, and environmental factors drive AMR at a national level remains limited. To explore associations between potential contributing factors and AMR, this study analyzed an extensive database comprising 13 major antibiotic-resistant bacteria and over 30 predictors (e.g., air pollution, antibiotic usage, economy, husbandry, public services, health services, education, diet, climate, and population) from 2014 to 2020 across China. The multivariate analysis results indicate that fine particulate matter with a diameter of 2.5 μm or less (PM2.5) is associated with AMR, accounting for 12% of the variation, followed by residents’ income (10.3%) and antibiotic usage density (5.1%). A reduction in PM2.5 of 1 µg·m−3 is linked to a 0.17% decrease in aggregate antibiotic resistance (p < 0.001, R2 = 0.74). Under different scenarios of China’s PM2.5 air-quality projections, we further estimated the premature death toll and economic burden derived from PM2.5-related antibiotic resistance in China until 2060. PM2.5-derived AMR is estimated to cause approximately 27 000 (95% confidence interval (CI): 6468–48 830) premature deaths and about 0.51 (0.12–0.92) million years of life lost annually in China, equivalent to an annual welfare loss of 8.4 (2.0–15.0) billion USD. Implementing the “Ambitious Pollution 1.5 ℃ Goals” scenario to reduce PM2.5 concentrations could prevent roughly 14 000 (3324–26 320) premature deaths—with a potential monetary value of 9.8 (2.2–17.6) billion USD—from AMR by 2060. These results suggest that reducing air pollution may offer co-benefits in the health and economic sectors by mitigating AMR.

Problems and Solutions of the Aviation Industry in the Post-epidemic Era

Three years after the outbreak, the year 2023 has officially entered the post-epidemic era. The aviation industry, which was severely hit by the epidemic, is gradually recovering. This article describes the current situation of the aviation industry after the epidemic, taking the Civil Aviation of China (CAAC) as the subject of the study, and analyses the problems it faces: the number of international flights has been slow to recover and unable to meet market demand; the financial crisis has been highlighted due to severe losses; supply chain shortages have prevented the timely delivery of aircraft; and the rapid increase in environmental pollution has led to a serious decarbonization situation. Potential solutions were also proposed for these four problems. These include increasing the number of flights through government consultation and communication, increasing revenue streams and reducing unnecessary spending to tide over the financial crisis, achieving supply chain resilience to avoid the obstacles posed by supply chain shortages, and developing new sustainable technologies for aviation to reduce air pollution.

Air Quality Awareness—Empirical Evidence from a Comparative Perspective between Two European Cities

This research, conducted as part of the European project PA-MAP (Participatory Approach to Monitoring Air Quality in Urban Environments), investigates citizens’ perceptions of air pollution in two European cities: Turin (Italy) and Dublin (Ireland). We systematically collected social data through semi-structured surveys distributed via online platforms. Our aim was to gather comprehensive information on the perception of pollution sources and the effectiveness of control systems. We examined citizens’ habits and their suggestions to improve air quality. The results revealed the following: (1) In Turin, the perception of air pollution significantly influences individuals’ self-assessments of health. Consequently, increased vigilance is required to mitigate environmental health risks and to disseminate information on air quality and effective practices for reducing air pollution. (2) The use of sustainable transportation in Turin is hindered due to the inadequate maintenance of cycling infrastructure. Citizens prefer to use cars or trains, which facilitate rapid travel. (3) In Dublin, greater sensitivity to the problem of air pollution has emerged, and the use of sustainable means of transport is facilitated via ad hoc infrastructure. These results provide empirical evidence to policymakers to support the promotion of concrete local actions through which to improve air quality.

"Smart Parking Systems: Enhancing Efficiency and Sustainability in Urban Areas"

Abstract: Smart Parking systems are innovative solutions designed to address the challenges faced by drivers when searching for parking spaces, especially in busy urban areas during peak hours. These systems utilize IoT technology deployed on-site to monitor and indicate the availability status of individual parking spaces. Additionally, a mobile application is provided to enable users to conveniently check the availability of parking spaces and easily locate vacant slots. By implementing a Smart Parking system, drivers can save valuable time and avoid the frustrations associated with the daunting task of finding suitable parking spots. Moreover, these systems play a crucial role in alleviating traffic congestion and reducing air pollution in densely populated urban areas.

Human or robot? Exploring different avatar appearances to increase perceived security in shared automated vehicles

Shared Automated Vehicles (SAVs) promise to make automated mobility accessible to a wide range of people while reducing air pollution and improving traffic flow. In the future, these vehicles will operate with no human driver on board, which poses several challenges that might differ depending on the cultural context and make one-fits-all solutions demanding. A promising substitute for the driver could be Digital Companions (DCs), i.e. conversational agents presented on a screen inside the vehicles. We conducted interviews with Colombian participants and workshops with German and Korean participants and derived two design concepts of DCs as an alternative for the human driver on SAVs: a human-like and a robot-like. We compared these two concepts to a baseline without companion using a scenario-based online questionnaire with participants from Colombia (N = 57), Germany (N = 50), and Korea (N = 29) measuring anxiety, security, trust, risk, control, threat, and user experience. In comparison with the baseline, both DCs are statistically significantly perceived as more positively. While we found a preference for the human-like DC among all participants, this preference is higher among Colombians while Koreans show the highest openness towards the robot-like DC.

One Health Ecological Approach to Sustainable Wireless Energy Transfer Aboard Electric Vehicles for Smart Cities

This investigation is part of a topical situation where wireless equipment is gradually being used for energy transfer, particularly for autonomous systems and the use of decarbonized energies. A characteristic example of decarbonized autonomous use is linked to the substitution of thermal engine vehicles for electric vehicles (EVs) equipped with energy storage batteries. This response was considered in an ecological context of reducing air pollution and defending planetary biodiversity, which are currently vital. These EVs ultimately operate thanks to the wireless charging of their batteries when stationary or running. By changing long-established means of transport that have become a threat to biodiversity, it is necessary to ensure that innovative replacement solutions protect this biodiversity. In addition, the construction of wireless power transfer (WPT) battery chargers for these EVs must offer an optimal ecology of clean energy saving. In such a context, the two concepts of One Health (OH) and Responsible Attitude (RA) will find their place in the design and control of WPT tools in EVs. This contribution aims to illustrate and analyze the roles of the green and non-wasteful OH and RA approaches in the design and control of WPT embedded in EVs for the smart city (SC) environment. In the paper, WPT tools are first introduced. The design and control of EV battery charging tools are then examined. The biological effects on living tissues due to the electromagnetic field (EMF) radiation of WPT are analyzed. The phenomena and equations governing the design of WPT and the effects of EMF radiation are then exposed. The OH and RA approaches in the SC context are afterward analyzed. The protection against the unsafe effects of WPT tools in the SC environment is consequently explored. The analyses followed in the paper are supported by examples from the literature. The explorations proposed in this contribution have made it possible to highlight certain notions, allowing a more in-depth understanding of the use of EVs with WPT rechargeable batteries for SCs. Thus, the analysis and fusion of these topics are at the heart of this contribution.

Empowering London Primary School Communities to Know and Tackle Air Pollution Exposure

This study tested the effectiveness of participatory methods to engage primary school communities in London with air pollution issues to help them identify, understand, and reduce their air pollution exposure. Three primary schools with high pollution levels participated in environmental educational activities, including air quality workshops and field campaigns involving different methods, time schedules, and project scopes. Participants completed surveys before and after these activities to measure their understanding, perceptions, and behavior. After the workshops, students admitted feeling more skillful in monitoring air quality and confident in incorporating this education into daily life and teaching others. They shared their results with peers, school leadership, and the community and led campaigns to help design experiments, choose measurement locations, and reduce air pollution exposure in schools. The results showed increased concern about air pollution, a better understanding of its causes and impacts, and more reported reduction behaviors. An Air Pollution Exposure Index (APEI) was combined with participatory monitoring data to raise awareness and understanding among students on typical school-day exposure. Feedback indicates that the tool was useful in defining air pollution exposure status and identifying exposure risks. Overall, this study contributes to the evidence of the feasibility and impact of student-led environmental education interventions These interventions involve collecting personalized exposure data, co-planning mitigations with school community groups, and employing methods to raise awareness of air pollution and empower pupils to identify potential solutions and change behaviors.

A Review of Urban Planning Approaches to Reduce Air Pollution Exposures.

With only 12% of the human population living in cities meeting the air quality standards set by the WHO guidelines, there is a critical need for coordinated strategies to meet the requirements of a healthy society. One pivotal mechanism for addressing societal expectations on air pollution and human health is to employ strategic modeling within the urban planning process. This review synthesizes research to inform coordinated strategies for a healthy society. Through strategic modeling in urban planning, we seek to uncover integrated solutions that mitigate air pollution, enhance public health, and create sustainable urban environments. Successful urban planning can help reduce air pollution by optimizing city design with regard to transportation systems. As one specific example, ventilation corridors i.e. aim to introduce natural wind into urban areas to improve thermal comfort and air quality, and they can be effective if well-designed and managed. However, physical barriers such as sound walls and vegetation must be carefully selected following design criteria with significant trade-offs that must be modeled quantitatively. These tradeoffs often involve balancing effectiveness, cost, aesthetics, and environmental impact. For instance, sound walls are highly effective at reducing noise, provide immediate impact, and are long-lasting. However, they are expensive to construct, visually unappealing, and may block views and sunlight. To address the costly issue of sound walls, a potential solution is implementing vegetation with a high leaf area index or leaf area density. This alternative is also an effective method for air pollution reduction with varying land-use potential. Ultimately, emission regulations are a key aspect of all such considerations. Given the broad range of developments, concerns, and considerations spanning city management, ventilation corridors, physical barriers, and transportation planning, this review aims to summarize the effect of a range of urban planning methods on air pollution considerations.

Balance point concentration: An indicator for classroom performance against outdoor PM2.5

Indoor air quality significantly affects occupants' health, making it crucial to evaluate a building's vulnerability to air pollution. In this study, 17 classrooms in urban areas of Seoul, Korea were monitored to determine how long a clean air environment can be maintained. We propose the balance point concentration (BPC) as the threshold value of outdoor PM2.5 concentration that can maintain PM2.5 in classrooms at the target value of 15 μg/m3. Based on the mass-balance equation, BPC is a comprehensive indicator that considers PM2.5 that can penetrate through building envelope, be generated from indoor activities, and be removed by an air purification system. For non-occupied classrooms, the BPC ranged from 20.6 to 34.3 μg/m3. We find that better airtightness reduced air pollution in buildings. However, due to students' activities, BPC decreased to 7.6–12.0 μg/m3. Lastly, in classrooms with mechanical ventilation systems in operation, the BPC ranged from 24.3 to 34.2 μg/m3, showing improved performance. Under such conditions, students can spend more than 88 % of the year in a classroom environment with clean air. In areas with low outdoor pollution levels, satisfaction can be even higher. Evaluating buildings performance using BPC allows for a more intuitive and clear assessment compared to existing indicators. When outdoor concentrations exceed BPC, additional air quality management in the classroom is necessary. This can be widely utilized when planning improvements to the environment or the operation of air purification system.

Fodder trees: Identification, leaf biomass yield, nutritional quality and socioeconomic importance in Essera district, Dawuro zone, southwest Ethiopia

The scarcity of feed in terms of quantity and quality tremendously impacts livestock productivity in Ethiopia. Using fodder trees (FTs) as livestock feed could partially overcome this gap. Thus, the present study aimed to identify species, estimate leaf biomass yield (LBY), evaluate nutritional quality and assess the socioeconomic importance of FTs in the Essera district. The study sites and households (HHs) were selected using a multistage sampling procedure. Data on the socioeconomic importance of FTs were collected from 134 randomly selected HHs. Ten FT species were evaluated for LBY determination, and 15 FTs (including nine FT species) were evaluated for nutritional quality across three agroecologies (AEs). In total, 34 FTs were identified at the species level. The overall mean of LBY of the FTs ranged from 14.32 to 370.94 kg/tree, with the lowest and highest values of 10.85 and 430.27 kg/tree at mid- and low-altitudes, respectively. A significant difference (p < 0.05) in the chemical composition of the selected FTs was observed between AEs. The overall mean of dry matter (DM), ash, crude protein (CP), neutral detergent fibre (NDF), acid detergent fibre (ADF), and acid detergent lignin (ADL) contents of the FTs ranged from 90.03 to 93.55 %, 6.26–16.52 %, 13.05–25.50 %, 33.06–50.42 %, 25.58–34.52 %, and 4.19–8.38 %, respectively. Moreover, the in vitro dry matter digestibility (IVDMD) of the FTs ranged from 37.80 to 67.89 %. The results indicated that the overall mean tannin, phytate, and oxalate contents were 2.84 ± 0.12 %, 0.60 ± 0.05 %, and 1.66 ± 0.21 %, respectively. Antinutritional factors (ANFs) were significantly (p < 0.05) influenced by FT species. In addition to feed sources, FTs were used for air pollution reduction (52.2 %), income generation (44.0 %), and soil erosion prevention (34.3 %) in the studied areas. In conclusion, due to the high CP content, high digestibility potential, low to moderate fibre and lignin contents, and tolerable levels of ANFs in FTs, the use of FTs as supplementary feed to livestock in the study area is recommended. Further experimental studies should be conducted on the impact of FTs on livestock performance.