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Great Lakes National Program Office Environmental Indicators |
Water Indicators
Clean water is fundamental to a healthy Great Lakes ecosystem.
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Trophic State
The trophic state of lakes is indicative of their biological productivity,
that is, the amount of living material supported within them, primarily in
the form of algae.
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Lake Erie
Phosphorus
Phosphorus is an essential element for all organisms and is found naturally
in tributaries and run-off waters. Excessive phosphorus can lead to
over-enrichment with algae and aquatic weeds and depletion of dissolved
oxygen as the excess plant and animal matter decay.
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Dissolved Oxygen
Depletion in Lake Erie Oxygen is essential for all plants and animals
to survive, whether they live on the land or in the water. The Central Basin
of Lake Erie is susceptible to low dissolved oxygen concentrations
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Beach Closings When bacteria standards are exceeded, local
authorities may close swimming at a beach or issue an advisory that water is
unhealthful for swimming.
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