This is a sample of my Down Under P/Cs, & below is what I wrote on the back, as an explanation of my interpretation;
"My card represents my country...
The 'red' depicts the desert, in the centre. Next the dry farming areas & stations. The 'green' represents the rain forests & coastal areas. The 'blues' resemble the ocean that surrounds our wonderful country."
I really had a lot of fun putting these P/Cs together, even though I took a lot longer than I had first planned.