1. Eutrophication

2. What is eutrophication?  The addition of nutrients to an aquatic ecosystem which causes an increased growth of autotrophs.

3.  Eutrophication can be a natural process of an aging lake. It happens when the nutrients added are greater than the nutrients used.  To be eutrophic means to be full of nutrients.  It is not always a bad thing for a lake to be eutrophic. Natural Eutrophication takes centuries to occur! Why does it occur?

4. The Human Effect  When humans add nutrients to a lake, and its inhabitants eventually suffer, this is called Artificial/Cultural Eutrophication.  The input of nutrients increases far beyond what the natural capacity of the lake should be. Cootes Paradise Google Earth July 2009

5. Top 4 Artificial Nutrient Sources: 1.Partially treated and untreated sewage (phosphates) 2.Runoff from agricultural sites (nitrates) 3.Home lawn fertilizer use. (nitrates) 4.Home detergent use (phosphates) and chemical fertilizers has greatly increased the amount of nitrates and phosphates that are washed into our lakes and ponds.

6. The Eutrophication Process http://youtu.be/UGqZsSuG7aohttp://youtu.be/UGqZsSuG7ao 1.29min  When phosphates and nitrates are added, the plants begin to grow explosively and algae takes off, or “blooms”.  Plants and algae consume greater amounts of oxygen in the water, robbing fish and other species of necessary oxygen.  The algae dies and falls to the bottom of the lake, bacteria decompose the plants (which requires oxygen).  The lack of oxygen results in the death of biotic factors below the surface of the water.  The cycle continues until the lake dies and…

7.  The lake eventually fills in.

8. 1. Nutrients added 2. Plants fertilized, increased growth 3. Plants increase, causing decreased light 4. Plants die, then decompose, causing decreased oxygen 5. Low oxygen, animals die 6. More decomposing plants and animals, less oxygen – continues until… The lake is dead except for surface plants

9. What can we do?  Reducing eutrophication should be a key concern when considering future laws and regulations  Sustainable solutions for everyone, including farmers and ranchers  Use phosphate-free soaps  ??? Ideas ???

10. Canada moves to cut phosphates to fight algae problem Last Updated: Saturday, February 16, 2008 | 7:43 PM ET CBC News The federal government has announced it will further limit the use of phosphates in household detergents to help control harmful blue-green algae growth in Canadian lakes and waterways. By 2010, all laundry and dishwasher detergents, and "if warranted" in some general household cleaners sold in Canada, will contain no more than 0.5 per cent phosphates by weight, federal Environment Minister John Baird said Friday in Montreal. At the moment, the phosphorus limit in laundry detergent is 2.2 per cent.CBC News