Nils Ericsson Terminal is the dirtiest, Angered’s City Park is the cleanest. Air pollution levels vary greatly between different places in Gothenburg. This is the finding of a new study led by researchers at the University of Gothenburg, which concludes that trees contribute to cleaner air in cities.

That green spaces can improve the quality of life and create a better climate in our cities is well known, but how important is vegetation for producing cleaner city air? This question is the focus of an extensive collaborative project led by researchers at University of Gothenburg.

In the project’s first study, the researchers measured pollutants in the air and compared them with pollutants on the leaves of deciduous (broadleaf) trees. The study looked at the pin oak (Quercus palustris), and sampling was made in June and September 2018. The study was conducted in seven urban settings in Gothenburg. The researchers chose to focus on PAHs, a group of air pollutants not yet studied closely but some of which are believed to be very harmful to human health.

Large differences between urban areas

At the same time, the researchers discovered that pollution levels varied greatly between different measurement sites. At the most polluted site – Nils Ericsson Terminal, the main bus station – the levels of PAHs were seven times higher than at Angered City Park on the periphery of the city.

“That the differences in pollution were so great between different parts of the city may seem surprising, and this is important information for the authorities to be aware of,” says Pleijel, who added that traffic is the primary source of air pollutants in the settings studied by the project.

Read the full article about trees and air quality by Ulrika Ernström at the University of Gothenburg.