Blue green algae is a type of bacteria that can produce their own food through photosynthesis, just like plants do. This is why they are green in color. This alga is typically known as cyanobacteria and lives in lakes, ponds, marine water, or even brackish water. Blue green algae in lakes can form what are known as Blooms. This phenomenon looks like green scum, foam, or a mat across the top of the water.
Not only is this floating muck often unsightly, but it also tends to smell as the cyanobacteria die. Some forms of this algae are more toxic than others and most cause irritation when they come into contact with skin. Despite having negative effects, these algae might be responsible for the air on Earth today. Three billion year old fossils have been found and the algae are thought to have been the main producers of oxygen long ago.
A lot of the algae attach themselves to rocks or submerged plants in the lake. The more nutrient rich a freshwater lake is, the more prevalent algal blooms are. Other than the amount of nutrients, additional factors that determine how much of this algae is present in a lake are; pH, light, and temperature. Most blooms are seen during the summer or early autumn, since this time period is perfect weather for the spread of this green algae.
Algae blooms are often thought of to be a nuisance when they occur in a lake that is used for recreational enjoyment. Swimming areas are closed off when the blooms are present and boating isn’t as desired in these areas either. An abundance of this type of algae can definitely put a damper on the tourist industry for some areas.
Some benefits of blue green algae include being used as a fertilizer, food source, and in medical products. This type of algae is added to rice paddies and soil for fertilization. The algae add organic matter and nitrogen to the soil, which increases the productivity of land and crops can be grown in otherwise barren soils. Erosion of the land is also slowed down by the addition of blue green algae taken off of lakes, since it binds to the soil particles.
Spirulina is a type of this algae that can be grown in fresh water and consumed by humans. It is high in protein and amino acids. All the amino acids a human being needs are contained in Spirulina and the protein content is around 60%.
Poisonous varieties of blue green algae also occur in lakes. These are the type responsible for the death of cows and other farm animals. Some dogs have even been poisoned by blue green algae in lakes. They are often drinking out of the same lakes as many other wild animals and aren’t immune to the effects of the algae.
Humans who have come into contact with the poisonous variety of blue green algae get a variety of unpleasant symptoms; red or sore throat, vomiting, diarrhea, itching eyes, red skin around the eyes, nausea, and headache. Be very aware of the water quality of any lake you enter, in order to avoid this unpleasantness.