• The coastal States of India may not suffer from the massive algal bloom that has been reported from the Arabian Sea.
• Ocean-watchers had earlier reported that a bloom of the size of Mexico, which originated in the Gulf of Oman, had reached the Arabian Sea and feared that it could reach Indian shores.
• Those at the Indian National Centre for Ocean Information Services, (INCOIS), Hyderabad, confirmed that the algal species green Noctiluca scintillans had bloomed.
• The presence of the green algae gives deep green colour to the ocean in the areas of spread.
• Researchers at INCOIS say that the current bloom was unlikely to impact the coastal States of the country.
• “When Noctiluca cells degrade, associated detritus in the form of particulate organic carbon sinks to deeper waters.
• During this process, decomposition occurs by the microbes and oxygen that is dissolved in water is consumed for their oxidation.”

Effect:

• The decomposition reduces dissolved oxygen from the water column and causes adverse effect on fish.
• Secondly, degrading Noctiluca cells release ammonia in the water increasing toxic level and it causes fish mortality, he explained.
• Cool dry continental air from the northeast causes an increase in surface density of the sea water due to evaporative cooling and increased salinity.”
• The “vertical mixing of the water masses causes recharge of water column with nutrients from the deep.
• The resulting nutrient enrichment increases the biological production” of the water.

Source: The Hindu