ST. PAUL, Minn. – Researchers are finding that a common stormwater contaminant — duckweed — is a serious threat to global warming. A University of Minnesota doctoral student, Joe Rabaey, said tests in the Metro area have found duckweed-infected ponds emitting three times more of the greenhouse gas methane as other ponds. Methane, Ravaey noted, is 30 times more potent in global warming than carbon dioxide. Duckweed, he said, thrives in stormwater ponds across Minnesota. Duckweed may look like blue-green algae, but it’s actually a small flowering plant that’s harmful, he said. What to do? Ravaey said fountains can break up the growth. Also, he said, the plant can be scooped out of ponds and left t0 dry out, wither and die. There is an upside: Ravaey said duckweed absorbs metal contaminants and stores them,. The metal can be purged by scooping the plant out of the water..
Duckweed. Not really algae but a gas-emitting flowering plant that over-generates methane and adds to global warming.