Salton Sea and Extremophiles Study Notes

National Wildlife Refuge: A Salty Dilemma

Overview of the Salton Sea

• The Salton Sea is referred to as a terminal lake, meaning it has no outlet.
• Primarily affected by agricultural runoff, the lake's salinity increases over time.
• Annually, approximately 1.6 million acre-feet of water are added, concentrating salts within the lake.

Salinity Levels

• The salinity level of the Salton Sea is currently 25% saltier than the Pacific Ocean.
• As salinity levels continue to rise, there is concern that the lake may eventually become too salty to support any fish life.
• This could have devastating implications for the local ecosystem, particularly affecting the food web that supports birds and other wildlife.

Bacterial Species

• A halophile is defined as a bacterium that thrives in high-salinity environments.
• Statistics illustrating salinity comparisons:
  • Salinity of the Salton Sea: 34 parts per thousand (ppt)
  • For perspective:
  • Pacific Ocean: 3.4% salinity (calculated as: 34 = 0.034 x 100)
  • Lake Tahoe: Estimated salinity of 0.5%, classifying its bacteria as non-halophile.

Extremophiles

• There are frequently asked questions regarding the physical and chemical boundaries for life, particularly under extreme conditions.
• These conditions can include:
  • High sodium salt concentration
  • Alkaline pH or acidic pH
  • Elevated temperature
• Organisms that thrive in such conditions are referred to as poly-extremophiles (as noted in Bowers et al., 2009).

Locations of Poly-extremophiles

• The Dead Sea (located between Israel and Jordan) is known for extreme salinity.
• The Great Salt Lake in Utah serves as another example of high salinity levels.
• Lake Magadi in Kenya also hosts organisms adapted to extremely saline environments.