What drives a harmful algae bloom? They occur in freshwater and saltwater. Blooms (HABs) are not just inconvenient, but actually can be dangerous. Besides killing fish and other aquatic life, blooms of cyanobacteria can result in water that’s toxic to animals and humans. What is the root cause of such blooms, and what can we reasonably do about them?
In the 2018 event in Longboat Key, Florida that led to tons of dead fish, a smell so awful people would gag with one inhale, empty beaches, empty roads, and empty restaurants, they blamed red tide. Another algae problem also plagues Florida's waterways: Blue-green algae, which has a direct correlation to agricultural and urban runoff.
Non-point nutrient loading is a technical term that describes agricultural fertilizers that flush into water. When soil scientists develop fertilizer blends, they typically do not consider nature’s nutrient balance. All living cells are comprised of a similar ratio of carbon, nitrogen and phosphorus. When this ratio is skewed, lifeforms like algae can develop in volumes that starve out other creatures and create a mono-culture.
Phosphorus in water is a big problem, because algae can pull whatever nitrogen it needs from the atmosphere, and carbon is almost always readily available. Bottom line, if you feel you need to fertilize, then do so organically. Organics provide nature’s natural ratio of nutrients. These cycle into the microbes that form biofilm. Biofilm in turn is the base material for periphyton, which launches the freshwater food web, and also figures strongly in the marine food web, particularly near shorelines. Periphyton is the most basic food source for aquatic life.
What can you do personally beyond going organic? Employ nature’s wetland effect around any water you are associated with. The two big factors that define nature’s wetland effect are “surface area” and “circulation.” Certainly, there are many other factors, like temperature, residence time, and many more. But surface area and circulation will help water. When you do this, you can steer nutrients into fish and other beneficial life forms. Essentially, grow fish instead of algae. BIoHavens are a form of constructed wetland. They concentrate nature’s wetland effect. They may be part of a solution for your waterway.
Today Floating Island International’s network of professional water stewards is designing island archipelagos that scale up to fix large waterways. Best of all, these massive projects are projected to pay for themselves, on a practical basis. Check out our Solar BioHaven page for details.
Here is an HAB story associated with this summer’s massive Red Tide event off of Florida’s coast.