Concentrations of Four Major Air Pollutants among Ecological Functional Zones in Shenyang, Northeast China

Abstract

Air pollution is a critical urban environmental issue in China; however, the relationships between air pollutants and ecological functional zones in urban areas are poorly understood. Therefore, we analyzed the spatiotemporal characteristics of four major air pollutants (particulate matter less than or equal to 2.5 µm (PM2.5) and 10 µm (PM10) in diameter, SO2, and NO2) concentrations over five ecological functional zones in Shenyang, Liaoning Province, at hourly, seasonal, and annual scales using data collected from 11 monitoring stations over 2 years. We further assessed the relationships between these pollutants and meteorological conditions and land-use types at the local scale. Peaks in PM, SO2, and NO2 concentrations occurred at 08:00–09:00 and 23:00 in all five zones. Daytime PM concentrations were highest in the industrial zone, and those of SO2 and NO2 were highest in residential areas. All four air pollutants reached their highest concentrations in winter and lowest in summer. The highest mean seasonal PM concentrations were found in the industrial zone, and the highest SO2 and NO2 concentrations were found in residential areas. The mean annual PM and SO2 concentrations decreased in 2017 in all zones, while that of NO2 increased in all zones excluding the cultural zone. The natural reserve zone had the lowest concentrations of all pollutants at all temporal scales. Pollutant concentrations of PM2.5, PM10, SO2, and NO2 were correlated with visibility, and their correlation coefficients are 0.675, 0.579, 0.475, and 0.477. Land coverage with buildings and natural vegetation negatively and positively influence air pollutant concentrations, respectively.

Effects of COVID-19 pandemic on the air quality of three megacities in India

“…Like higher air temperature, higher wind speed also facilitates the dispersal of pollutants ( Li et al, 2020 ), except for some pollutants like PM 10 , which gets resuspended at the ground level due to higher wind speed ( Zhang et al, 2018 ). Mumbai did not exhibit any significant difference in wind speed between the pre-lockdown and lockdown phase; however, the difference was noticeable in the case of Kolkata and Delhi.…”

Visibility Prediction over South Korea Based on Random Forest

“…The urban region has populations exceeding 1 million and are located away from the coast, namely Seoul (#108), Suwon (#119), Cheongju (#131), Daegu (#143), and Gwangju (#156); the island region has populations less than 500,000, namely Ulleungdo (#115), Heuksando (#169), Gosan (#185), Seongsan (#188), and Jindogun (#268). Notably, the urban region experienced similar temperatures to the island region due to urban heat island effects but experienced fewer precipitation days, lower wind speeds, and higher concentrations of air pollutants [8,22,78].…”

“…Visibility is often measured using networks of visibility sensors, such as Vaisala or Biral sensors, and can reach 300 km when only Rayleigh scattering and gas absorption are taken into account [4]; however, distances of 145-225 km are typical for unpolluted atmospheric conditions, and distances of 10-100 km are commonly recorded [5]. Importantly, precipitation and air pollution can have significant impacts on visibility, with low-visibility conditions of a few kilometers not uncommon [6], and such effects have impacts on weather and climate change [7,8]. In addition, low visibility is linked to socioeconomic losses, including road and air traffic accidents and public health risks [9][10][11].…”

Background Concentrations of Cultivable, Mesophilic Bacteria and Dust Particles in the Air in Urban, Rural and Mountain Regions

“…Buchunde et al (2019) detected a diurnal variation of fine and coarse particles with an increase in the morning and evening hours [ 47 ] most likely due to rush hour. In the study of Li et al (2020) the highest mean of seasonal particle concentrations was found in the industrial zone with peaks during morning rush hour [ 48 ]. High levels of particulate matter, observed in large cities around the world, give cause for concern about their short and long-term effects on public health.…”