Unexplained biological changes in the Lake Erie ecosystem will be the focus of the study, which began yesterday. EPA's Great Lakes National Program Office, Environment Canada and scientists from more than 20 universities and institutes will participate in the study, which launched from Cleveland aboard EPA's RV Lake Guardian research vessel.
The ship will serve as a base for the summer-long field season of this two-year project to solve the puzzle of trend changes in Lake Erie's central basin since 1990. Researchers are looking at three patterns that are inconsistent with the usual dynamics of lake functions. They will explore:
- Why chlorophyll is at historically low levels.
- Why phosphorus is increasing in Lake Erie water, when the amount of phosphorus going into the lake is not increasing.
- Why there is a "dead zone," an area essentially devoid of oxygen, in the summer.
"We have tracked Lake Erie for decades and thought we had a good historical understanding of what to expect now and in the future," said Thomas Skinner, Region 5 administrator and Great Lakes National Program Manager. "But the recent discovery of sudden biological changes, which could have long-term effects on the ecosystem, prompted this all-out investigation."
The study will bring together experts in the biology and chemistry of lakes to look at the possibility that zebra mussels or other invading species, an increase in ultraviolet light, or that a variety of chemicals may be changing the workings of the lake.