Context

• According to theAgharkar Research Institute, the colour of Lonar lake water in Maharashtra’s Buldhana district turned pink due to a large presence of the salt-loving ‘Haloarchaea’ microbes.

Key Findings:

• It has been assumed that the absence of rain, less human interference (owing to lockdown) and high temperature resulted in the evaporation of water which increased its salinity and pH.
• The increased salinity and pH facilitated the growth of halophilic microbes, mainly Haloarchaea.
• Haloarchaea or halophilic archaea is a bacteria culture which produces pink pigment and is found in water saturated with salt.
• Because of the biomass of Haloarchaea microbes, the surface of the water turned red or pink. As the biomass subsides, the colour will disappear.
• The colour of the lake is now returning to original as the rainy season has kicked in, allowing dilution of the water. The salinity and pH/alkalinity levels have also come down and green algae have started growing in the water body.
• Further, it was noted that Haloarchaea microbes were ingested by Flamingos.
• These microbes acted as carotenoid (pigment) rich food for the birds.
• Flamingos get their red-pink colour from special colouring chemicals called pigments found in the algae and invertebrates they eat.

Back to Basics:

Lonar Lake

• Also known as Lonar crater, is a saline and alkaline lake located at Lonar in Buldhana district, Maharashtra.
• It is situated inside the Deccan Plateau—a massive plain of volcanic basalt rock created by eruptions.
• It is an oval shaped and has a mean diameter of 1.2 km. It is a popular tourist hub.
• It is a notified National Geo-heritage Monument.
  • Geo-heritage refers to the geological features which are inherently or culturally significant offering insight to earth’s evolution or history to earth science or that can be utilized for education.
  • Geological Survey of India (GSI)is the parent body which is making efforts towards identification and protection of geo-heritage sites.
  • It is believed to have been created over 52,000 years ago when a meteorite hit the Earth.