Michigander
06-11-2001, 02:25 AM
TOXIC ALGAE RETURNS TO LAKE ERIE
A thick layer of vibrant blue-green sludge on a lake is a sign of trouble. The sludge is a bloom of toxic algae that can sicken people and kill animals if they drink it. This blue-green algae used to be a big problem on Lake Erie during the 1970s. Tight pollution laws helped bring it under control, but now the algae is back in western Lake Erie. A scientist says part of the problem has to do with another pest -- the zebra mussel.
David Culver is a zoologist with the Sea Grant program at The Ohio State University. He says zebra mussels eat almost anything that''s floating in the water, but they draw the line at toxic blue-green algae.
"If you give them big lumps of it, they will spit it out, sort of like a baby the first time it runs into creamed spinach."
The problem is that any of this stuff that goes into a zebra mussel comes out in concentrated form, and that makes it especially poisonous to any fish that eat it.
Culver says zebra mussels might not eat much of the toxic algae but they are helping to feed it. There are billions of the tiny clam-like critters in Lake Erie, and they''re speeding up the natural cycle of nutrients in the lake. Without the mussels, organic matter in the water would settle to the bottom and be eaten and digested by bacteria, insects, and worms. Their digestion would gradually release nitrogen and phosphorus back into the water. The zebra mussels do the same thing, but they do it faster, and that produces more of the nutrients that feed the toxic algae at the surface.
Culver says this effect of the zebra mussels might require even tighter pollution restrictions.
"We'll have to work all the harder to decrease the loading of phosphorus and nitrogen from outside the lake if we want to discourage the growth of toxic algae."
Culver says better farm management and sewage treatment will help curb the blooms.
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Is this BS or another problem ?
A thick layer of vibrant blue-green sludge on a lake is a sign of trouble. The sludge is a bloom of toxic algae that can sicken people and kill animals if they drink it. This blue-green algae used to be a big problem on Lake Erie during the 1970s. Tight pollution laws helped bring it under control, but now the algae is back in western Lake Erie. A scientist says part of the problem has to do with another pest -- the zebra mussel.
David Culver is a zoologist with the Sea Grant program at The Ohio State University. He says zebra mussels eat almost anything that''s floating in the water, but they draw the line at toxic blue-green algae.
"If you give them big lumps of it, they will spit it out, sort of like a baby the first time it runs into creamed spinach."
The problem is that any of this stuff that goes into a zebra mussel comes out in concentrated form, and that makes it especially poisonous to any fish that eat it.
Culver says zebra mussels might not eat much of the toxic algae but they are helping to feed it. There are billions of the tiny clam-like critters in Lake Erie, and they''re speeding up the natural cycle of nutrients in the lake. Without the mussels, organic matter in the water would settle to the bottom and be eaten and digested by bacteria, insects, and worms. Their digestion would gradually release nitrogen and phosphorus back into the water. The zebra mussels do the same thing, but they do it faster, and that produces more of the nutrients that feed the toxic algae at the surface.
Culver says this effect of the zebra mussels might require even tighter pollution restrictions.
"We'll have to work all the harder to decrease the loading of phosphorus and nitrogen from outside the lake if we want to discourage the growth of toxic algae."
Culver says better farm management and sewage treatment will help curb the blooms.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Is this BS or another problem ?