BIOROCK- THE HINDU
• The Zoological Survey of India (ZSI), with help from Gujarat’s forest department, is attempting for the first time a process to restore coral reefs using biorock or mineral accretion technology.
• A biorock structure was installed one nautical mile off the Mithapur coast in the Gulf of Kachchh on January 19.
• Biorock is the name given to the substance formed by electro accumulation of minerals dissolved in seawater on steel structures that are lowered onto the sea bed and are connected to a power source, in this case solar panels that float on the surface.
• The technology works by passing a small amount of electrical current through electrodes in the water.
• When a positively charged anode and negatively charged cathode are placed on the sea floor, with an electric current flowing between them, calcium ions combine with carbonate ions and adhere to the structure (cathode).
• This results in calcium carbonate formation. Coral larvae adhere to the CaCO3 and grow quickly.
• The location for installing the biorock had been chosen keeping in mind the high tidal amplitude in the Gulf of Kachchh.
• The low tide depth where the biorock has been installed is four metres, and at high tide it is about eight metres.
A coral reef is an underwater ecosystem characterized by reef-building corals. Reefs are formed of colonies of coral polyps held together by calcium carbonate. Most coral reefs are built from stony corals, whose polyps cluster in groups.