This is covered by:
AQA 8035, Cambridge IGCSE, CEA, Edexcel A, Edexcel B, Eduqas A, OCR A, OCR B, WJEC
Sand Dune Regeneration
Sand dune regenation involves either repairing damaged dunes or creating new ones. The process usually involves planting more vegetation to bind the sand together, protecting the dunes behind fencing so humans don’t trample all over them, and placing ‘sand traps’ in the dune area to catch and retain wind-blown sand.
Where existing dunes are being eroded the reason why the dunes are being destroyed has to be established before anything can be done to protect them. Obviously if the dunes are being undercut by waves the regeneration plan will be different to the one employed where dunes are being eroded by too many people walking across them.
Once the cause of the problem has been identified, a rejuvination plan is created and put into practice.
Typcal solutions are as follows.
Too much human activity in the dunes
Fencing to keep people out of the dune area, and “official paths” through the dunes on wooden boardwalks so people’s feet don’t damage the sand and vegetation. Once the people have been removed from the dunes, they can be replanted with grasses , the roots of which will bind the sand together.
Wind breaks are positioned upwind of the dunes and at stages throughout the dunes to act like groynes on a beach. The wind break blocks the wind and allows sand to build up on the sheltered side of the barriers. The wind breaks may look like traditional fences,or be bundles of sticks, vegetation etc designed to trap sand articles as they are blown past. Additional vegetation is then planted on the deposited sand to stablise it and prevent further erosion.
This is a more difficult problem to solve because it’s very difficult to protect a soft dunes from high tide waves twice a day, every day of the year. Barriers fixed in the sand tend to be undercut and destroyed quickly by the waves, and unprotected extra planting is just washed away. Porous matting may be placed over the part of the dune suffering from erosion, made either from plastics or naturalmaterials such as hessian sacking or mats of heather stems bound together.
In more serious cases there is little that can be done other than reprofiling the beach or encouraging the growth of the dunes on the side furthest away from the waves.