19 Winning Photos From Nat Geo's 2016 Nature Photographer Contest That Will Inspire Your Next Trip

"Eighty percent of the San Francisco Bay Area wetlands — 16,500 acres — has been developed for salt mining. Water is channeled into these large ponds, leaves through evaporation, and the salt is then collected. The tint of each pond is an indication of its salinity. Microorganisms inside the pond change color according to the salinity of its environment. This high-salinity salt pond is located right next to Facebook headquarters, where about 4,000 people work every day."