Will this green wall improve air quality in London?

I love the look of this green wall, installed last November to trap pollution at one on London’s busiest intersections  - the corner of Edgeware and Marylebone roads. It covers 200 square metres, is made up of 15 different evergreen and perennial plants (chosen to absorb pollution from exhaust fumes) and despite the gritty environment, seems to be thriving.

It's planted in an abstract pattern – unlike the green wall inspired by a Van Gogh painting which last year appeared outside the National Gallery in Trafalgar Square. The effectiveness is being monitored by scientists from Imperial College. It’s part of an initiative to promote cleaner air in the capital. Around 500 new trees and shrubs have appeared, including 200 lime trees along the A40 and 50 planted towers on Lower Thames St. With the Olympics coming up, London’s poor air quality is a hot topic, and this green initiative is seen as an attractive way of helping improve the situation.