Sand dune succession on calcareous and salacious sands

Caption: Sand dunes composed of calcareous sands often derived from the remains of marine animals will have extensive grassland. Dune heath only occurs in the older dunes where leaching has removed the calcium carbonate from the surface soils to create a more acidic environment.

Caption: Where the original sand is deficient in shell fragments the development of dune heath occurs much earlier in the succession.