In this particular scene there are 5 surface layers + the base layer. The last one in the stack is the sandy looking surface along the shore line (which is a fake stone shader). The rest are surface layers with a PF in the color function slot of each one. The bottom surface layer (first in stack) is at 1 on the coverage. The rest are various values of coverage constrained by altitude and slope. Each scene will be different depending on the terrain and what the artist is trying to convey.
