Should you ever fly over San Francisco Bay, be sure to peer out of the window in order to catch a glimpse of one of the world's most incredibly coloured landscapes. It's hard to believe that the cause of such a vibrant display is plain old salt.These beautifully coloured patches are in fact salt evaporation ponds; wetlands now dedicated to salt production. The Kite Aerial Photography website explains the colouring brilliantly;
'The palette of colors that makes the salt ponds such a vibrant sight reflects a complex ecosystem. Colors in salt ponds range from pale green to deep coral pink, and indicate the salinity of the ponds. Microorganisms create these spectacular colors, changing their own hues in response to increasing salinity. In low-to mid-salinity ponds, green algae proliferate, lending the water a green cast. As the salinity increases, an algae called Dunaliella out-competes the other microorganisms in the pond, and the color shifts to an even lighter shade of green. In mid-to high-salinity ponds, high salt concentrations actually cause the Dunaliella to produce a red pigment. Millions of tiny brine shrimp in mid-salinity ponds contribute an orange cast to the water. Halophilic (salt-loving) bacteria such as Stichococcus also contribute red tints to high-salinity brine. Weather can affect the colors of the ponds. When wind creates choppy conditions, the colors appear murkier. Heavy rain can dilute the brine, causing the colors to shift toward the hues found in lower-salinity ponds or even turn the water clear.'
So hey, sometimes algae isn't all that bad :-). Check it out: