Why is it in the News?

Scientists have discovered a lake that could be a good match for Darwin's "warm little ponds" where life got started on the primordial Earth.

What is a Soda Lake?

• A soda lake is a lake with a pH value of more than the usual measure of 6 or 7, usually between 9 and 11.
• High carbonate concentration, especially sodium carbonate, is responsible for the alkalinity of the water.
  • A soda lake may also contain a high concentration of sodium chloride and other salts making it saline or hypersaline Lake.
• Soda lakes are highly productive ecosystems compared to freshwater lakes with a global primary production rate of over 10 grams of carbon per square meter per day.
• Therefore Soda lakes are the most productive aquatic environment on Earth because of the availability of dissolved carbon dioxide.
• Soda lakes occur naturally in both arid and semi-arid areas.

Geology And Genesis Of Soda Lakes:

• A topography that limits the outflow of water from the lake is needed.
• An endorheic basin is formed when the water is confined without the outflow.
• The pH of the water in the depression rises through the evaporation of the lake which requires a suitable climate like the desert climate to balance between the inflow and evaporation.
  •  The rate at which carbonate salt dissolves in the lake water depends on the ecology of the surrounding area.
• The relative absence of magnesium and calcium is critical in the formation of the soda lake since magnesium or calcium is likely to dissolve quickly and displace the carbonate ion thus neutralizing the PH of the lake water.

Biodiversity Of Soda Lakes:

• Soda lakes are inhabited by a rich diversity of microbial life making them a productive ecosystem.
• They are permanent and seasonal habitats for algae which are visible in many of the lakes.
• Soda lakes are dominated by prokaryotes like bacteria and archaea, especially in lakes with higher levels of alkalinity.
• Multicellular organisms such as brine shrimp and fish are found in plenty if not most of the soda lakes.
• Soda lakes also harbour unique species which are adapted to the alkali conditions.
  • These organisms which are adapted to the high alkalinity are called haloalkaliphiles.

Examples Of Soda Lakes:

• Africa and Asia have the highest number of soda lakes since the two continents have vast desert conditions which are perfect for the formation of soda lakes.
  • Most of the soda lakes in Africa are located in Eastern Africa, especially in Kenya, Tanzania, and Ethiopia.
• Lake Natron in Tanzania is one of the most outstanding soda lakes in Africa because of the high PH of water which is always about 12.
• India and China have the highest number of soda lakes in Asia.
  • Some of the soda lakes in India include Tso Kar Salt Lake, Pangong Salt Lake, and Lonar Lake.