Abstract
Mixed-vegetation planting patterns are commonly seen in urban areas for specific reasons like aesthetic, cooling, and particle deposition effects of the vegetation. However, they may have a negative impact on human health by worsening the air quality inside the street canyon due to the decreased air exchange rate. From the view of precise control of pollutant concentration in the sensitive areas of people’s concern in the existed street canyons, thirty-four cases with different vegetation planting patterns and pressure loss coefficients (λ) are studied numerically to investigate the effects of vegetation on airflow and pollutant dispersion inside the canyon. The cases of treeless and 2 rows of tree planting patterns in wind-tunnel measurements were selected for the model validation. The results demonstrate that compared to the treeless case, the greenbelts can greatly change the airflow features and reduce the pollutant concentration at the leeward side, while the only-tree planting patterns have little impact on the flow and deteriorate dispersion within the street canyon. Moreover, rows of greenbelts planted under the corresponding trees can reduce the average pollutant concentrations on the leeward wall and the footpath of the street canyon by up to 22.6% and 33.2%, respectively. Besides, the pattern of 1 row of trees with 1 row of greenbelts planted in the street canyon center should be suggested as the optimal mixed vegetation configuration in this study. That is because compared to the treeless case the pollutant concentration on leeward wall, windward wall, leeward footpath, and windward footpath can be reduced by 14.2%, 10.0%, 24.6%, and 37%, respectively. It is helpful to the city planners to consider whether the disadvantages of planting vegetation inside the street canyon would overwhelm the advantages.
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The datasets used and/or analyzed during the current study are available from the corresponding author on reasonable request.
References
Abhijith KV, Gokhale S (2015) Passive control potentials of trees and on-street parked cars in reduction of air pollution exposure in urban street canyons. Environ Pollut (Barking, Essex : 1987) 204:99–108. https://doi.org/10.1016/j.envpol.2015.04.013
Abhijith KV, Kumar P, Gallagher J, McNabola A, Baldauf R, Pilla F, Broderick B, Di Sabatino S, Pulvirenti B (2017) Air pollution abatement performances of green infrastructure in open road and built-up street canyon environments – a review. Atmos Environ 162:71–86. https://doi.org/10.1016/j.atmosenv.2017.05.014
Ai ZT, Mak CM (2017) CFD simulation of flow in a long street canyon under a perpendicular wind direction: evaluation of three computational settings. Build Environ 114:293–306. https://doi.org/10.1016/j.buildenv.2016.12.032
Al-Dabbous AN, Kumar P (2014) The influence of roadside vegetation barriers on airborne nanoparticles and pedestrians exposure under varying wind conditions. Atmos Environ 90:113–124. https://doi.org/10.1016/j.atmosenv.2014.03.040
Allegrini J, Dorer V, Carmeliet J (2013) Wind tunnel measurements of buoyant flows in street canyons. Build Environ 59:315–326. https://doi.org/10.1016/j.buildenv.2012.08.029
Allegrini J, Dorer V, Carmeliet J (2015) Coupled CFD, radiation and building energy model for studying heat fluxes in an urban environment with generic building configurations. Sustain Cities Soc 19:385–394. https://doi.org/10.1016/j.scs.2015.07.009
Bengana Y, Loiseau J-C, Robinet J-C, Tuckerman LS (2019) Bifurcation analysis and frequency prediction in shear-driven cavity flow. J Fluid Mech 875:725–757. https://doi.org/10.1017/jfm.2019.422
Buccolieri R, Gromke C, Di Sabatino S, Ruck B (2009) Aerodynamic effects of trees on pollutant concentration in street canyons. Sci Total Environ 407(19):5247–5256. https://doi.org/10.1016/j.scitotenv.2009.06.016
Cetin M (2019) The effect of urban planning on urban formations determining bioclimatic comfort area’s effect using satellitia imagines on air quality: a case study of Bursa city. Air Qual Atmos Hlth 12(10):1237–1249. https://doi.org/10.1007/s11869-019-00742-4
Cetin M, Jawed AA (2022) Variation of Ba concentrations in some plants grown in Pakistan depending on traffic density. Biomass Convers Bior. https://doi.org/10.1007/s13399-022-02334-2
Chen G, Wang D, Wang Q, Li Y, Wang X, Hang J, Gao P, Ou C, Wang K (2020) Scaled outdoor experimental studies of urban thermal environment in street canyon models with various aspect ratios and thermal storage. Sci Total Environ 726:138147. https://doi.org/10.1016/j.scitotenv.2020.138147
Chen Q (2009) Ventilation performance prediction for buildings: a method overview and recent applications. Build Environ 44(4):848–858. https://doi.org/10.1016/j.buildenv.2008.05.025
Chen X, Wang X, Wu X, Guo J, Zhou Z (2021) Influence of roadside vegetation barriers on air quality inside urban street canyons. Urban For Urban Gree 63:127219. https://doi.org/10.1016/j.ufug.2021.127219
Chew LW, Aliabadi AA, Norford LK (2018) Flows across high aspect ratio street canyons: Reynolds number independence revisited. Environ Fluid Mech 18(5):1275–1291. https://doi.org/10.1007/s10652-018-9601-0
Cui P, Li Z, Tao W-Q (2016) Wind-tunnel measurements for thermal effects on the air flow and pollutant dispersion through different scale urban areas. Build Environ 97:137–151. https://doi.org/10.1016/j.buildenv.2015.12.010
Dallman A, Magnusson S, Britter R, Norford L, Entekhabi D, Fernando H (2014) Conditions for thermal circulation in urban street canyons. Build Environ 80:184–191. https://doi.org/10.1016/j.buildenv.2014.05.014
Edussuriya P, Chan A, Ye A (2011) Urban morphology and air quality in dense residential environments in Hong Kong Part I: District-level analysis. Atmos Environ 45(27):4789–4803. https://doi.org/10.1016/j.atmosenv.2009.07.061
Gousseau P, Blocken B, van Heijst GJF (2011) CFD simulation of pollutant dispersion around isolated buildings: on the role of convective and turbulent mass fluxes in the prediction accuracy. J Hazard Mater 194:422–434. https://doi.org/10.1016/j.jhazmat.2011.08.008
Gromke C, Blocken B (2015) Influence of avenue-trees on air quality at the urban neighborhood scale. Part I: quality assurance studies and turbulent Schmidt number analysis for RANS CFD simulations. Environ Pollut (Barking, Essex : 1987) 196:214–223. https://doi.org/10.1016/j.envpol.2014.10.016
Gromke C, Buccolieri R, Di Sabatino S, Ruck B (2008) Dispersion study in a street canyon with tree planting by means of wind tunnel and numerical investigations – evaluation of CFD data with experimental data. Atmos Environ 42(37):8640–8650. https://doi.org/10.1016/j.atmosenv.2008.08.019
Gromke C, Jamarkattel N, Ruck B (2016) Influence of roadside hedgerows on air quality in urban street canyons. Atmos Environ 139:75–86. https://doi.org/10.1016/j.atmosenv.2016.05.014
Gromke C, Ruck B (2007) Influence of trees on the dispersion of pollutants in an urban street canyon—experimental investigation of the flow and concentration field. Atmos Environ 41(16):3287–3302. https://doi.org/10.1016/j.atmosenv.2006.12.043
Gromke C, Ruck B (2009) On the impact of trees on dispersion processes of traffic emissions in street canyons. Bound-Lay Meteorol 131(1):19–34. https://doi.org/10.1007/s10546-008-9301-2
Gromke C, Ruck B (2012) Pollutant concentrations in street canyons of different aspect ratio with avenues of trees for various wind directions. Bound-Lay Meteorol 144(1):41–64. https://doi.org/10.1007/s10546-012-9703-z
Hanna S, Chang J (2012) Acceptance criteria for urban dispersion model evaluation. Meteorol Atmos Phys 116(3–4):133–146. https://doi.org/10.1007/s00703-011-0177-1
Huang Y, Lei C, Liu C-H, Perez P, Forehead H, Kong S, Zhou JL (2021) A review of strategies for mitigating roadside air pollution in urban street canyons. Environ Pollut (Barking, Essex : 1987) 280:116971. https://doi.org/10.1016/j.envpol.2021.116971
Huang Y, Li M, Ren S, Wang M, Cui P (2019) Impacts of tree-planting pattern and trunk height on the airflow and pollutant dispersion inside a street canyon. Build Environ 165:106385. https://doi.org/10.1016/j.buildenv.2019.106385
Hunter LJ, Watson ID, Johnson GT (1990) Modelling air flow regimes in urban canyons. Energ Buildings 15(3):315–324. https://doi.org/10.1016/0378-7788(90)90004-3
Jin S, Guo J, Wheeler S, Kan L, Che S (2014) Evaluation of impacts of trees on PM2.5 dispersion in urban streets. Atmos Environ 99:277–287. https://doi.org/10.1016/j.atmosenv.2014.10.002
Kubilay A, Derome D, Carmeliet J (2019) Impact of evaporative cooling due to wetting of urban materials on local thermal comfort in a street canyon. Sustain Cities Soc 49:101574. https://doi.org/10.1016/j.scs.2019.101574
Li Z, Ming T, Liu S, Peng C, de Richter R, Li W, Zhang H, Wen C-Y (2021) Review on pollutant dispersion in urban areas-part A: effects of mechanical factors and urban morphology. Build Environ 190:107534. https://doi.org/10.1016/j.buildenv.2020.107534
Li Z, Zhang H, Wen C-Y, Yang A-S, Juan Y-H (2021) The effects of lateral entrainment on pollutant dispersion inside a street canyon and the corresponding optimal urban design strategies. Build Environ 195:107740. https://doi.org/10.1016/j.buildenv.2021.107740
Li X, Liu C, Leung D (2005) Development of a model for the determination of air exchange rates for street canyons. Atmos Environ 39(38):7285–7296. https://doi.org/10.1016/j.atmosenv.2005.09.007
Li X, Liu C, Leung D, Lam K (2006) Recent progress in CFD modelling of wind field and pollutant transport in street canyons. Atmos Environ 40(29):5640–5658. https://doi.org/10.1016/j.atmosenv.2006.04.055
Liu Y, Huang Y, Zhang Z, Wang K, Luo Y, Cui P (2022) Impacts of green walls on the characteristics of thermo-flow and photochemical reaction kinetics within street canyons. Urban For Urban Gree 72:127568. https://doi.org/10.1016/j.ufug.2022.127568
Liu C, Leung D, Barth M (2005) On the prediction of air and pollutant exchange rates in street canyons of different aspect ratios using large-eddy simulation. Atmos Environ. https://doi.org/10.1016/j.atmosenv.2004.08.036
Lozano R, Fullman N, Abate D, Abay SM, Abbafati C, Abbasi N et al (2018) Measuring progress from 1990 to 2017 and projecting attainment to 2030 of the health-related Sustainable Development Goals for 195 countries and territories: a systematic analysis for the Global Burden of Disease Study 2017. Lancet 392(10159):2091–2138. https://doi.org/10.1016/S0140-6736(18)32281-5
Moradpour M, Afshin H, Farhanieh B (2017) A numerical investigation of reactive air pollutant dispersion in urban street canyons with tree planting. Atmos Pollut Res 8(2):253–266. https://doi.org/10.1016/j.apr.2016.09.002
Nosek Š, Kukačka L, Jurčáková K, Kellnerová R, Jaňour Z (2017) Impact of roof height non-uniformity on pollutant transport between a street canyon and intersections. Environ Pollut (Barking, Essex : 1987) 227:125–138. https://doi.org/10.1016/j.envpol.2017.03.073
Peng Y, Buccolieri R, Gao Z, Ding W (2020) Indices employed for the assessment of “urban outdoor ventilation” - a review. Atmos Environ 223:117211. https://doi.org/10.1016/j.atmosenv.2019.117211
Salim SM, Buccolieri R, Chan A, Di Sabatino S (2011a) Numerical simulation of atmospheric pollutant dispersion in an urban street canyon: comparison between RANS and LES. J Wind Eng Ind Aerod 99(2–3):103–113. https://doi.org/10.1016/j.jweia.2010.12.002
Salim SM, Cheah SC, Chan A (2011b) Numerical simulation of dispersion in urban street canyons with avenue-like tree plantings: comparison between RANS and LES. Build Environ 46(9):1735–1746. https://doi.org/10.1016/j.buildenv.2011.01.032
Sanz C (2003) A note on k - ε modelling of vegetation canopy air-flows. Bound-Lay Meteorol 108(1):191–197. https://doi.org/10.1023/A:1023066012766
Sha C, Wang X, Lin Y, Fan Y, Chen X, Hang J (2018) The impact of urban open space and “lift-up” building design on building intake fraction and daily pollutant exposure in idealized urban models. Sci Total Environ 633:1314–1328. https://doi.org/10.1016/j.scitotenv.2018.03.194
Shen J-W, Cui P, Huang Y, Luo Y, Guan J (2022) New insights into quantifying deposition and aerodynamic characteristics of PM2.5 removal by different tree leaves. Air Qual Atmos Hlth 15(8):1341–1356. https://doi.org/10.1007/s11869-022-01157-4
Thom AS (1971) Momentum absorption by vegetation. Q J Roy Meteor Soc 97(414):414–428
Tominaga Y, Mochida A, Yoshie R, Kataoka H, Nozu T, Yoshikawa M, Shirasawa T (2008) AIJ guidelines for practical applications of CFD to pedestrian wind environment around buildings. J Wind Eng Ind Aerod 96(10–11):1749–1761. https://doi.org/10.1016/j.jweia.2008.02.058
United Nations, Department of Economic and Social Affairs, Population Division (2018) World Urbanization Prospects The 2018 Revision. https://www.un.org/development/desa/en/news/population/2018-revision-of-world-urbanization-prospects.html
Xue F, Li X (2017) The impact of roadside trees on traffic released PM 10 in urban street canyon: aerodynamic and deposition effects. Sustain Cities Soc 30:195–204. https://doi.org/10.1016/j.scs.2017.02.001
Yang H, Lam CKC, Lin Y, Chen L, Mattsson M, Sandberg M, Hayati A, Claesson L, Hang J (2021) Numerical investigations of re-independence and influence of wall heating on flow characteristics and ventilation in full-scale 2D street canyons. Build Environ 189:107510. https://doi.org/10.1016/j.buildenv.2020.107510
Zhang K, Chen G, Zhang Y, Liu S, Wang X, Wang B, Hang J (2020) Integrated impacts of turbulent mixing and NOX-O3 photochemistry on reactive pollutant dispersion and intake fraction in shallow and deep street canyons. Sci Total Environ 712:135553. https://doi.org/10.1016/j.scitotenv.2019.135553
Zhao Y, Chew LW, Kubilay A, Carmeliet J (2020) Isothermal and non-isothermal flow in street canyons: a review from theoretical, experimental and numerical perspectives. Build Environ 184:107163. https://doi.org/10.1016/j.buildenv.2020.107163
Funding
This work was supported by National Natural Science Foundation of China (Grant No. 42277477, 52106102, and 52070127) and Scientific and Innovative Action Plan of Shanghai (No. 20dz1204000).
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Jiaowen Shen is the lead author of this paper, and has contributed to design and carry out the numerical simulation study and originally drafted this paper.
Pengyi Cui, as the second author, has contributed to guide the simulation method and the paper revision.
Yuandong Huang, as the corresponding author, has mainly contributed to supervise the research direction and the paper revision and provide resources.
Yiping Wu and Yang Luo have carefully edited the grammar, spelling, and sentence structures of this paper.
Chung Hyok Sin has mainly contributed to check and edit the figures.
Jie Guan has provided resources and funding for this paper.
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Shen, J., Cui, P., Huang, Y. et al. New insights on precise regulation of pollutant distribution inside a street canyon by different vegetation planting patterns. Environ Sci Pollut Res 30, 63148–63174 (2023). https://doi.org/10.1007/s11356-023-26370-1
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DOI: https://doi.org/10.1007/s11356-023-26370-1