Lake Urmia (or Ormiyeh) is one of the largest hypersaline lakes in …

• Abstract
• Background
• Geology
• Sediments
• Hydrology
• The basin
• Morphometry
• Causeway project
• Hydrochemistry
• Main ions
• Exploitation
• Artemia biology
• Bisexual vs. parthenogenetic Artemia
• Ecology
• Phytoplankton
• Bacteriology
• Conservation and management
• Acknowledgements
• References
• Figures

The seasonal biologic cycle in Urmia Lake leads to the precipitation of aragonite in surface waters [1] induced by shifts in CO₂ levels, due largely to biological activity [21]. Remarkably, the second most important component in the lake sediments consists of small rod-shaped fecal pellets of the brine shrimp Artemia. X-ray analyses show that the pellets are composed of 80 % aragonite along with small amounts of quartz and calcite, and rarely dolomite; true oolites have been found in only one locality in shoals along the western margin, north of Gulman Khaneh [1].