By Doris Prado, Property Manager
Runoff from fertilizers, contaminated soil and other products can pollute your pond or lake and deposit high levels of nitrogen and phosphorus. Blue green algae feed on these deposits—so as more of these nutrients become available, more algae will form.
What is the brown stuff floating in our lake?
Algae are everywhere, in oceans, in freshwater lakes and rivers, on land, and even in the air we breathe. Sometimes called pond scum or seaweed, they are a natural part of any aquatic environment. Algae and fungi can live together in a form called lichens on rocks, walls, and trees.
There are many factors that influence the growth of algae within a lake. Most algae growth is caused by a combination of the following factors; rainfall, fertilizer run-off (nutrients), water clarity, temperature, depth and bottom sediment composition.
Algae bloom growth is most common in the summer when rainfall and lake temperatures increase.
Summer rains cause fertilizer run-off to enter a lake directly through drainage pipes. This fertilizer run-off carries nutrients (lawn fertilizers and decaying plant material such as grass clippings) in the form of nitrogen and phosphorous into the lake. Because algae is a plant, it absorbs these nutrients just like your lawns and landscaping. Populations increase rapidly. Within 3-5 days an algae bloom can occur. This growth will occur anywhere sunlight reaches the bottom sediments (composition – high nutrient source). If a lake is shallow (depth) or has a shallow area and is clear (high water clarity), algae growth can be higher.
Most algae growth is caused by a combination of the following factors; rainfall, fertilizer run-off (nutrients), water clarity, temperature, depth and bottom sediment composition.