Baron Opal wrote:
Those are salt ponds, and the colours are photosynthesising halobacteria — ones that use retinal and rhodopsin rather than chlorophyl. Let those rather than cyanobacteria become endosymbiotes or evolve multicellular forms and you would have just such orange and magenta leaves.
How novel, are they growing the bacteria specifically, or is having some salt containment the key part?
I gather that they are evaporating seawater to obtain salt and perhaps other minerals. The salinity of the ponds is too high for most forms of life; it kills algae and cyanobacteria. The salt-tolerating extremophiles that survive happen to photosynthesise using retinal, and the absence of green photosynthesisers (a) allows them to proliferate to an degree seldom seen elsewhere and (b) makes their colour obvious because is not mixed with green as usual.
I don't know, but I suspect that the orange colour of some of the ponds is the result of their still having a small proportion of chlorophyll-bearing and carotenoid-photosynthesising organisms in them.
I will have to research this; I've never heard of it except in some aboriginal societies where they gather salt from sea water for trade.
Salt is obtained commercially both from mineral deposits and by evaporation of seawater. There are some very large salt ponds in Western Australia — e.g. at Karratha, Onslow, and Useless Loop — where the product is scraped off the bed using large bulldozers. The evaporation ponds at Onslow are large enough to be visible from orbit
Start your researches with the Wikipedia article on "Salt evaporation pond"