Salt ponds in the San Francisco Bay Area. Salt Ponds range from blue green to deep magenta, they are colored naturally by the microorganisms that thrive as salinity levels increase. Fremont, Alameda County, California, USA

Roughly 8,000 acres along the South San Francisco Bay are devoted to salt evaporation ponds. The salt ponds range from blue green to deep magenta, three microorganisms in particular, Synechococcus, Halobacteria, and Dunaliella, influence the color of salt ponds. Fremont, Alameda County, California, USA. © march. 10 2008 Marco van Middelkoop/Aerophoto-Schiphol