A team led by researchers at the University of Washington has discovered a major cause for a drop in nighttime pollinator activity — and people are largely to blame.
A team led by researchers at the University of Washington has discovered a major cause for a drop in nighttime pollinator activity — and people are largely to blame.
The researchers found that nitrate radicals (NO3) in the air degrade the scent chemicals released by a common wildflower, drastically reducing the scent-based cues that nighttime pollinators rely on to locate the flower. In the atmosphere, NO3 is produced by chemical reactions among other nitrogen oxides, which are themselves released by the combustion of gas and coal from cars, power plants and other sources. The findings, published Feb. 9 in the journal Science, are the first to show how nighttime pollution creates a chain of chemical reactions that degrades scent cues, leaving flowers undetectable by smell. The researchers also determined that pollution likely has worldwide impacts on pollination.
The team — co-led by Jeff Riffell, a UW professor of biology, and Joel Thornton, a UW professor of atmospheric sciences — studied the pale evening primrose (Oenothera pallida). This wildflower grows in arid environments across the western U.S. They chose this species because its white flowers emit a scent that attracts a diverse group of pollinators, including nocturnal moths, which are one of its most important pollinators.
Read more at University of Washington
Image: Image of a field site in eastern Washington showing pale evening primrose flowers. (Credit: Jeremy Chan/University of Washington)
