The study by the UK Green Wall Centre in Staffordshire looked at this green wall at New Street station, Birmingham.
It found ‘promising potential for removal of atmospheric PM (PM1, PM2.5 and PM10). The researchers noted that careful species selection is crucial to optimize living walls as PM filters. ‘Smaller-leaved species, hairy leaf surfaces and [waxy leaves] enhance the PM capture potential of living wall-plants.’
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