Why are some lakes full of algae and thick plants?
Plants naturally grow in and around lakes, but sometimes lakes and ponds can get an overgrowth of plants, algae, or bacteria. In many cases, humans are responsible. Chemicals that are used on lawns and in agriculture (like nitrogen and potassium) wash into our water systems. Once there, plants and algae have a feast on this “food”.
Sometimes overgrowths of cyanobacteria (called “blooms”) can make the water scummy and turn it a blue-green color (or other colors). Cyanobacteria produce compounds that impact the taste and odor of water, make fish unpalatable, and even produce toxins that affect human health. Scientists are still studying the causes of these blooms.
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Microscopic view of blue green algae sample. Some algae produce toxins that threaten the health and safety of living things that come in direct contact. Cyanobacteria - Scytonema (blue green algae)
Cyanobacteria - Phormidium (blue green algae)
Microscopic view of blue green algae sample. Some algae produce toxins that threaten the health and safety of living things that come in direct contact. Cyanobacteria - Phormidium (blue green algae)
Landsat Image of Cyanobacteria
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Collecting a sample from a cyanobacterial bloom
USGS scientist collecting a sample from a cyanobacterial bloom from Milford Lake, KS; Sept. 2, 2011.
Algal Toxin Photo
Creek filled with Algal Toxins is surrounded by plant life on both banks. Trees line the background.
Cyanobacteria - Nostoc (blue green algae)
Microscopic view of blue green algae sample. Some algae produce toxins that threaten the health and safety of living things that come in direct contact. Cyanobacteria - Nostoc (blue green algae)
Cyanobacteria - Dolichospermum (blue green algae)
Microscopic view of blue green algae sample. Some algae produce toxins that threaten the health and safety of living things that come in direct contact. Cyanobacteria - Dolichospermum (blue green algae)
Harmful Algal Bloom (HAB) in a stream
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A view of an algal bloom in Upper Klamath Lake from field sampling boat.