Environmental Law & Economics: Phosphates and Nitrogen. Not global warming.

Radovan Kazda
Environmental Policy Analyst
Conservative Institute of M. R. Stefanik

Friday, August 01, 2008

Phosphates and Nitrogen. Not global warming.

Ed Struzik, Canwest News Service, Published: Tuesday, July 22, 2008 (link)

EXCERPT: After a remarkable 37-year experiment, University of Alberta scientist David Schindler and his colleagues have finally nailed down the chemical triggers for a problem that plagues thousands of freshwater and coastal ecosystems around the world.

Fifty years ago, no one knew what exactly caused algae blooms to appear on lakes and rivers. There was some evidence to suggest that carbon, nitrogen and phosphorous, which are associated with agricultural runoff and waste water, were responsible. But small-scale experiments weren’t able to show which were more important.

Schindler seemed to solve the problem when he and his colleagues conducted a number of groundbreaking experiments in northern Ontario in the 1960s and early 1970s. In a famous 1974 aerial photograph published by the journal Science, two portions of their experimental Lake 226 were highlighted. One side was treated with carbon, nitrogen and phosphorous. The other was treated with just carbon and nitrogen.

The side receiving phosphorous rapidly developed a huge bloom of blue-green algae. The side not receiving phosphorous remained in near-pristine condition.

Schindler’s latest series of long-term experiments shows that nitrogen removal completely fails to control blue-green algae blooms. He proved this by manipulating nitrogen and phosphorus levels on Lake 227 for 37 years. Nitrogen control, he found, only encouraged algae blooms.

Read more…

Conclusion? Phosphates and Nitrogen. Not global warming. (link)

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