Plankton,
Base Of Food Supply, In Big Decline
Despite their tiny size, plant plankton found
in the world's oceans are crucial to much of
life on Earth. They are the foundation of the
bountiful marine food web, produce half the
world's oxygen and suck up harmful carbon
dioxide. And they are declining sharply.
Worldwide phytoplankton levels are down 40
percent since the 1950s, according to a study
published Wednesday in the journal Nature. The
likely cause is global warming, which makes it
hard for the plant plankton to get vital
nutrients, researchers say. The numbers are
both staggering and disturbing, say the
Canadian scientists who did the study and a
top U.S. government scientist. "It's
concerning because phytoplankton is the basic
currency for everything going on in the
ocean," said Dalhousie University biology
professor Boris Worm, a study co-author.
"It's almost like a recession ... that
has been going on for decades." Half a
million datapoints dating to 1899 show that
plant plankton levels in nearly all of the
world's oceans started to drop in the 1950s.
The biggest changes are in the Arctic,
southern and equatorial Atlantic and
equatorial Pacific oceans. Only the Indian
Ocean is not showing a decline. The study's
authors said it's too early to say that plant
plankton is on the verge of vanishing.