Aeolian dune morphology is controlled by three interacting factors classically shown on a ternary (ratio) diagram: sand supply, wind strength/energy, and vegetation cover. High sand supply combined with strong, effective winds and minimal vegetation favors transverse dunes (dune ridges oriented perpendicular to wind); limited sand supply combined with strong winds and minimal vegetation favors longitudinal dunes (ridges aligned parallel to the dominant wind); moderate sand supply with some vegetation cover favors parabolic dunes (vegetation anchors the dune arms while the center migrates); and high vegetation cover, regardless of sand supply or wind strength, suppresses dune development entirely (no dunes).
Reading the triangular diagram, whose three corners/axes represent sand supply, wind strength, and vegetation cover: point A, positioned toward the vertex associated with strong wind...
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