LETTERS: Biologist expands on statement
To the Editor:
The Nov. 17 article, "Conservation may have caused outbreak, nature may correct it," summarized a public meeting concerning the blue-green algae problem at Marion Reservoir. While the article quoted me accurately, I would like to expand on my statement.
Conservation efforts of Marion Reservoir 319 Water Quality Project and Marion County Conservation District have increased lake clarity, and that is a good thing.
The work Peggy Blackman and the many buffer initiative cooperators do to reduce soil-borne nutrients washing into Marion Reservoir is critical to improve water quality at the lake.
Algae require food and sunlight to thrive. Their food is phosphorous and nitrogen released from lake sediments and water entering from Cottonwood Creek into Marion Reservoir. Clear lake water allows sunlight to penetrate deeper into the lake and existing phosphorous and nitrogen concentrations are so high that algae continues to grow resulting in bloom conditions. In the short term, it is very likely we will continue to see increased algae growth. In the long term however, conservation practices will reduce available nutrients, and algae populations will decline. Eventually, with the nutrient supply decreased, the algae will decline to the point where annual blooms do not occur.
It may take several years for Marion Reservoir to reach the point at which the blue-green algae is under control but conservation efforts of buffer initiative cooperators are the key to success and can be a model for others to follow.
Jim Harris
Environmental Biologist
