2.0 Biophysical Interactions

The four spheres functioning together- The accretion cycle

• Coastal Dune Systems are formed by the interactions between the atmosphere, lithosphere, hydrosphere and biosphere.
• The predominant process that shows how the four spheres interact on Coastal Sand Dunes along the SE coast of Australia is called the ACCRETION CYCLE.
• Simply, the accretion cycle is a process that helps deposit, store and remove sand on Coastal Sand Dunes.
• The ACCRETION CYCLE plays a major role in the functioning of The Stockton Coastal Dune Ecosystem
• This cycle is a complex process where the lithosphere, hydrosphere, atmosphere and biosphere create, build up, store and remove of sand in the dune system in a constant cycle.
• This cycle often begins with sand that has been eroded and transported by rivers and along the coastline are deposited onto the shore by waves. The sand dries out and is blown to the back of the beach where it is stored with the help of the vegetation. Sand is then taken back into the sea via destructive waves and currents and stored offshore but it is deposited back slowly with constructive waves. And the cycle continues.

The Diagram Below Shows Some of the Biophysical Components interacting in a Coastal Sand Dune Ecosystem