Researchers have grown a farm of rooftop vegetables bathed in the CO2-rich exhaust air from city buildings—a somewhat dystopian idea which nevertheless boosted plant growth by an incredible 400%.
Their research turns building vents into an unlikely companion to food production. Many people will recognize these silver, mushroom-shaped structures that are visible on urban roofs: they form part of HVAC systems that pump out stale air and ventilate buildings with fresh air from outside. In buildings where lots of people live and work, the CO2 emissions from human respiration can reach surprisingly high levels, which is why these systems are needed to keep the air fresh and unpolluted.
But for the researchers on the new study, the thinking was, why let all that pent-up CO2 vanish into thin air when it’s a key ingredient in fertilizing plants and promoting their growth?
The majority of urban dwellers spend their time indoors—and so cities have a potentially huge and steady supply of CO2 that’s going untapped. These wasted emissions “can be used as a resource to create better-growing conditions for plants,” says Sarabeth Buckley, a plant scientist at the University of Cambridge and lead author on the study.
So between 2018 and 2019, Buckley and colleagues started their experiment on the roof of the Boston University campus in the United States, a building heavily populated by students during term time.
Read the complete article at www.anthropocenemagazine.org.