The Lake Book

OUR IMPACT ON ECOSYSTEMS
For many thousands of years, from the time the ice sheets receded
until European colonization, our lakes were protected by the forested
watersheds draining into them. Vegetation intercepted rain so less fell
to the forest floor. Loose soils and duff (accumulated leaves on the
forest floor) absorbed excess rain. The little remaining runoff carried
minimal nutrients to lakes. Lakes were in balance.
After colonists arrived, land was cleared for farming, and forests were
cut on an unprecedented scale. More recently, roads, bridges, parking
lots, and homes have reduced the amount of forests in many lake
watersheds. Instead of absorbing rain, these impervious surfaces
prevent water from soaking in and increase the
amount of stormwater runoff. Runoff then gathers
Graphics by L. Diemer, FBE. Crayfish,
Daphnia, and Copepod images by IAN
symbols. Excavator from OpenClipArt.
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