Land seen from above

Geometry is a giveaway. A perfect circle of green is an irrigation arm pivoting around a central well, which is why the square corners stay dry. Rows curving with the contour rather than straight down a slope are erosion control. Land that is flat, rectangular and thoroughly drained was not found in that state — it was made.

Colour is chemistry and biology. Ponds that shift from green to orange to red are seawater concentrating stage by stage, each stage taken over by a different salt-tolerant microbe. A hard line between green and desert is where irrigation stops. Parcels of different colours on one hillside at the same moment means separate owners, and that pattern is usually inheritance over centuries.