Lonar Lake water changes colour
The water of the Lonar Lake in Buldana district in Maharashtra has reverted back to its original colour green. The lake had turned red causing much concern, and investigations were started to identify the cause. Lonar lake is one of the largest crater lakes in the world and was created by a meteorite impact in basalt rock over 52000 years ago. The lake is alkaline and has an average diameter of about 1.2 kilometres. This phenomenon has been seen in other parts of the world as well such as the Urmia lake in Iran in 2016. As per National Geographic, in late April 2016, NASA’s Aqua satellite captured Lake Urmia with a deep green hue, but by mid-July, water was filled with algae and bacteria and the colour turned to red. Mohammad Tourian, a scientist at the University of Stuttgart, was quoted as saying that in conditions of high salinity and light intensity, the micro-algae turns red due to the production of protective carotenoids in the cells. A family of bacteria called Halobacteriaceae could also be responsible as they use a red pigment to absorb sunlight and convert it into energy. So large quantities of them in the water may contribute to the change in colour.