Trees often better, cheaper than technology at mitigating air pollution

Nov. 6 (UPI) — Planting trees and shrubs around factories and power plants may be a better air pollution mitigation strategy than installing scrubbing technologies, according to a new study.

When researchers analyzed the potential of natural and technological mitigation strategies for dozens of pollution sources, including factories, roadways, power plants, oil and gas drilling sites and more, they found natural interventions were superior roughly 75 percent of the time.

The findings, published this week in the journal Environmental Science and Technology, showed natural remedies reduced air pollution by an average of 27 percent.

“The fact is that traditionally, especially as engineers, we don’t think about nature; we just focus on putting technology into everything,” lead study author Bhavik Bakshi, a professor of chemical and biomolecular engineering at Ohio State University, said in a news release. “And so, one key finding is that we need to start looking at nature and learning from it and respecting it. There are win-win opportunities if we do — opportunities that are potentially cheaper and better environmentally.”

Bakshi and his colleagues collected and analyzed public data on air pollution and vegetation in every county in the contiguous 48 states. In each county, researchers looked at the already existing vegetation, including trees, grasslands and shrubs, and calculated how much restorative planting would be necessary to return vegetation cover to county-average levels.

Scientists also calculated the impacts of restorative planting on county pollution levels, including levels of sulfur dioxide, particulate matter and nitrogen dioxide.

By restoring vegetation cover to each of the counties’ averages, air pollution could be reduced by an average of 27 percent across all of them. In 75 percent of counties, natural solutions were cheaper than using technology to achieve the same levels of air pollution reductions.

The study’s authors acknowledged that restorative vegetation is impossible in some counties, like in desert counties or in cities where there is not enough space. Ideally, natural and technological solutions to air pollution should be deployed together, researchers said.

“The thing that we are interested in is basically making sure that engineering contributes positively to sustainable development,” Bakshi said. “And one big reason why engineering has not done that is because engineering has kept nature outside of its system boundary.”