Analyzing temporal changes in urban forest structure and the effect on air quality improvement

Older trees in good health are expected to provide more ecosystem services and equivalent economic values due to their large size. The relationship of tree dimensions, respective tree height, crown area, diameter at breast height (dbh), and total leaf area vis-a-vis age were studied for 790 heritage trees ≥ 100 years old in Macau; 50 genera and 63 species were represented. Seven out of ten common genera showed no significant increase for all tested parameters except increase of dbh with age. Other factors, such as condition and geometry of growing spaces, controlled the performance of heritage trees, as well as the realization of their biological potential size, with implications on the provision of ecosystem services. The effects of these heritage trees on air-quality improvement and gross carbon sequestration were quantified by the i-Tree Eco model. Overall, 806.8 kg of air pollutants were removed annually, with benefits valued at US $8,091. The heritage trees stored 3,041 t carbon in total and sequestered 842 kg carbon/yr, equivalent to US $601 in annual benefits. The values were much higher than ordinary urban forest trees. Ten common heritage tree genera were ranked by their capacities for air quality improvement, carbon storage, and sequestration. The findings can serve as a decision tool for heritage tree management and conservation and to estimate potential ecosystem services of established trees

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Optimization of Biodiesel, Methanol and Methane Production and Air Quality Improvement

10.3390/books978-3-03928-101-5 ◽

2020 ◽

Keyword(s):

Quality Improvement ◽

Air Quality ◽

Methane Production ◽

Air Quality Improvement

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City-level air quality improvement in the Beijing-Tianjin-Hebei region from 2016/17 to 2017/18 heating seasons: Attributions and process analysis

Environmental Pollution ◽

10.1016/j.envpol.2021.116523 ◽

2021 ◽

Vol 274 ◽

pp. 116523

Author(s):

Yibo Zhang ◽

Xue Chen ◽

Shaocai Yu ◽

Liqiang Wang ◽

Zhen Li ◽

...

Keyword(s):

Quality Improvement ◽

Air Quality ◽

Process Analysis ◽

Air Quality Improvement

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Air quality improvement in a megacity: implications from 2015 Beijing Parade Blue pollution control actions

Atmospheric Chemistry and Physics ◽

10.5194/acp-17-31-2017 ◽

2017 ◽

Vol 17 (1) ◽

pp. 31-46 ◽

Cited By ~ 41

Author(s):

Wen Xu ◽

Wei Song ◽

Yangyang Zhang ◽

Xuejun Liu ◽

Lin Zhang ◽

...

Keyword(s):

Quality Improvement ◽

Air Quality ◽

Control Period ◽

Emission Control ◽

Monitoring Network ◽

Control Measures ◽

Integrated Analysis ◽

Air Quality Improvement ◽

Emission Control Measures ◽

Control Regions

Abstract. The implementation of strict emission control measures in Beijing and surrounding regions during the 2015 China Victory Day Parade provided a valuable opportunity to investigate related air quality improvements in a megacity. We measured NH3, NO2 and PM2.5 at multiple sites in and outside Beijing and summarized concentrations of PM2.5, PM10, NO2, SO2 and CO in 291 cities across China from a national urban air quality monitoring network between August and September 2015. Consistently significant reductions of 12–35 % for NH3 and 33–59 % for NO2 in different areas of Beijing during the emission control period (referred to as the Parade Blue period) were observed compared with measurements in the pre- and post-Parade Blue periods without emission controls. Average NH3 and NO2 concentrations at sites near traffic were strongly correlated and showed positive and significant responses to traffic reduction measures, suggesting that traffic is an important source of both NH3 and NOx in urban Beijing. Daily concentrations of PM2.5 and secondary inorganic aerosol (sulfate, ammonium and nitrate) at the urban and rural sites both decreased during the Parade Blue period. During (after) the emission control period, concentrations of PM2.5, PM10, NO2, SO2 and CO from the national city-monitoring network showed the largest decrease (increase) of 34–72 % (50–214 %) in Beijing, a smaller decrease (a moderate increase) of 1–32 % (16–44 %) in emission control regions outside Beijing and an increase (decrease) of 6–16 % (−2–7 %) in non-emission-control regions of China. Integrated analysis of modelling and monitoring results demonstrated that emission control measures made a major contribution to air quality improvement in Beijing compared with a minor contribution from favourable meteorological conditions during the Parade Blue period. These results show that controls of secondary aerosol precursors (NH3, SO2 and NOx) locally and regionally are key to curbing air pollution in Beijing and probably in other mega cities worldwide.

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The Economic Benefits of Air Quality Improvement in Arctic Council Countries

10.1787/9c46037d-en ◽

2021 ◽

Author(s):

Keyword(s):

Quality Improvement ◽

Air Quality ◽

Economic Benefits ◽

Arctic Council ◽

Air Quality Improvement

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Effects of the emergency control measures in Beijing on air quality improvement

Atmospheric Pollution Research ◽

10.1016/j.apr.2018.10.005 ◽

2019 ◽

Vol 10 (2) ◽

pp. 580-586 ◽

Cited By ~ 1

Author(s):

Jingyu Tian ◽

Tianqi Cai ◽

Jing Shang ◽

James J. Schauer ◽

Shujian Yang ◽

...

Keyword(s):

Quality Improvement ◽

Air Quality ◽

Control Measures ◽

Emergency Control ◽

Air Quality Improvement

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Assessment of on-road emissions of four Euro V diesel and CNG waste collection trucks for supporting air-quality improvement initiatives in the city of Milan

The Science of The Total Environment ◽

10.1016/j.scitotenv.2012.03.038 ◽

2012 ◽

Vol 426 ◽

pp. 65-72 ◽

Cited By ~ 52

Author(s):

Georgios Fontaras ◽

Giorgio Martini ◽

Urbano Manfredi ◽

Alessandro Marotta ◽

Alois Krasenbrink ◽

...

Keyword(s):

Quality Improvement ◽

Air Quality ◽

Waste Collection ◽

Air Quality Improvement ◽

The City

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Air Quality Improvement in a Megacity: Implications from 2015 Beijing Parade Blue Pollution-Control Actions

10.5194/acp-2016-591 ◽

2016 ◽

Author(s):

Wen Xu ◽

Wei Song ◽

Yangyang Zhang ◽

Xuejun Liu ◽

Lin Zhang ◽

...

Keyword(s):

Quality Improvement ◽

Air Quality ◽

Control Period ◽

Emission Control ◽

Monitoring Network ◽

Control Measures ◽

Integrated Analysis ◽

Beijing City ◽

Air Quality Improvement ◽

Emission Control Measures

Abstract. The implementation of strict emission control measures in Beijing and surrounding regions during the 2015 China Victory Day Parade provided a valuable opportunity to investigate related air quality improvements in a megacity. We measured NH3, NO2 and PM2.5 at multiple sites in and outside Beijing and summarized concentrations of PM2.5, PM10, NO2, SO2 and CO in 291 cities across China from a national urban air quality monitoring network between August and September 2015. Consistently significant reductions of 12–35 % for NH3 and 33–59 % for NO2 in different areas of Beijing city during the emission control period (referred to as the Parade Blue period) were observed compared with measurements in the pre- and post-Parade Blue periods without emission controls. Average NH3 and NO2 concentrations at sites near traffic were strongly correlated and showed positive and significant responses to traffic reduction measures, suggesting that traffic is an important source of both NH3 and NOx in urban Beijing. Daily concentrations of PM2.5 and secondary inorganic aerosol (sulfate, ammonium, and nitrate) at the urban and rural sites both decreased during the Parade Blue period. Concentrations of PM2.5, PM10, NO2, SO2 and CO from the national city-monitoring network showed the largest decrease (34–72 %) in Beijing, a smaller decrease (1–32 %) in North China (excluding Beijing), and an increase (6–16 %) in other regions of China during the emission control period. Integrated analysis of modeling and monitoring results demonstrated that emission control measures made a major contribution to air quality improvement in Beijing compared with a minor contribution from favorable meteorological conditions during the Parade Blue period. These results show that controls of secondary aerosol precursors (NH3, SO2 and NOx) locally and regionally are key to curbing air pollution in Beijing and probably in other mega cities worldwide.

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