Harmful algal blooms – HABs – occur when colonies of algae grow out of control and produce toxic or harmful effects on people, marine life, and birds. HABs occur naturally but their frequency and intensity are often associated with increased nutrient loading (mainly phosphorous and nitrogen) in bodies of water that is the result of runoff from sources like lawncare and agriculture.
Researchers at Florida Atlantic University have developed a technique for transforming cyanobacteria – also known as blue-green algae and a prime HAB material – into an effective material for removing phosphorous from water.
Their process converts blue-green algal biomass – essentially hazardous waste – into a custom-made adsorbent material that can pull harmful phosphorous from water. The algae is first quickly heated up using microwaves and then it is modified by adding lanthanum chloride.
The study took blue-green algae from Florida’s Lake Okeechobee, synthesized the adsorbent material in minutes, and using only small amounts of it could remove 90% of the phosphorous present in only half an hour. It worked perfectly well in the presence of natural organic matter. Using the harmful algae itself to prevent algal growth in bodies of water is an innovative way to reduce its further occurrence.
Phosphorous is a major contributor to the occurrence of harmful algal blooms, which can lead to toxic water conditions, loss of aquatic life, and significant economic losses for the fishing and tourism industries. This technique could prove to be an essential tool for managing the growing problem of nutrient pollution.
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FAU Engineering Develops New Weapon Against Harmful Algal Blooms
Photo, posted October 27, 2010, courtesy of Jennifer L. Graham / U.S. Geological Survey via Flickr.
Earth Wise is a production of WAMC Northeast Public Radio
