Keeping Wetlands Wet-
Wetlands can store huge amounts of a greenhouse gas, but
only as long as they stay wet.
By Kathleen Schmitt
Article courtesy of Great Lakes Radio Consortium
August 21, 2001
Wetlands around the world provide homes to all kinds
of fish and waterfowl, and they're also important because
of what they lock up within their boggy borders. It's
a whole load of carbon - so much that it's measured in
billions of tons. Researchers have now found that only
one chemical reaction keeps all that carbon from entering
the atmosphere and adding to global warming.
Chris Freeman wrote a paper on this subject that appeared
in the journal Nature. Freeman is a biologist at the University
of Wales. He says all plants absorb the greenhouse gas
carbon dioxide, and they usually release that carbon once
they die and decompose. But Freeman says dead waterlogged
plants in wetlands don't decompose much. As a result,
wetlands are storing a huge amount of carbon - as much
as what is already in the atmosphere.
Freeman says natural chemicals inhibit decomposition
in wetlands. But he recently discovered that these inhibitors
could be destroyed by a single type of enzyme. These enzymes
are found in all wetlands, but Freeman says they're usually
"What could happen in the future, though, is
that something could actually trigger these enzymes to
come back into action. If that did happen, it would actually
remove all of the inhibitors, and it would allow all of
the other enzymes in the system to start breaking down
this vast accumulation of stored up carbon dioxide and
release it back into the atmosphere."
Freeman says this could happen if global warming dries
out the wetlands and exposes them to air. Oxygen would
activate the enzyme, and that would release the stored
carbon into the atmosphere and probably make global warming
worse. To prevent this, Freeman says wetlands need to
be protected and global warming needs to be controlled.