WDNR News -- Staring down from space with an unsleeping eye, scientists are using satellites powerful lenses to peer into Wisconsin lakes and measure, on a grand scale, what human lake watchers and water scientists have been doing from a much lower vantage point, for decades.
"How many of us have stood on a lakeshore or a pier or been out on the water in a boat and stared into the water judging its quality by its clarity," said Karen von Huene, executive director of Wisconsin Lakes, a statewide organization working to protect and enhance water quality in Wisconsin lakes and a member of the Wisconsin Lakes Partnership. "Clear water is associated with health; cloudy, algae-choked or heavily colored water is usually thought of as dirty, unhealthy or downright toxic. And to a large extent, that is true."
Clarity is a fair measure of the amount of algae and plankton in a lake which in turn represent the amount of nutrients available. The suspended green particles or floating greenish or brownish mats that diminish clarity are usually plankton and algae. It's a fairly simple formula: the more nutrients, the more plankton and algae, leading to less clarity in the water.
Read on at: http://dnr.wi.gov/news/weekly/#art4