Lonar Lake

In News: A recent study has warned that Lonar Lake is facing ecological stress due to an unprecedented influx of fresh water, threatening its unique saline–alkaline ecosystem.

Reasons for Freshwater Influx

• Above-normal rainfall in the region
• Proliferation of borewells around the crater
• Borewell drilling has likely breached the impermeable basaltic rock layers, allowing freshwater to enter the lake basin

About Lonar Lake

Location

• Buldhana district, Maharashtra
• A closed-basin crater lake (lagoon-type)

Uniqueness

• World’s only known hyper-velocity impact crater formed entirely in basaltic rock
• Contains saline and alkaline water simultaneously
• Hosts extremophile microorganisms, making it valuable for astrobiological studies

Formation

• Formed about 52,000 years ago
• Caused by a meteorite impact on the Deccan basalt plateau
• The impact energy created a near-circular crater with raised rims

Ecological Significance

• Supports unique microbial life adapted to extreme salinity and alkalinity
• Acts as a natural laboratory for studying:
• Impact craters
• Extremophiles
• Climate–hydrology interactions

Conservation Status

• Ramsar Site (designated in 2020)
• Declared a National Geo-heritage Monument by the Geological Survey of India (GSI)

Environmental Concern

• Influx of freshwater can:
• Alter lake chemistry
• Disrupt microbial balance
• Threaten endemic biodiversity
• Highlights the impact of unsustainable groundwater extraction on fragile geo-ecosystems