Onshore winds (winds blowing inland from the sea) cause the formation of sand dunes at the back of a beach. Sand is deposited by the wind around an object such as a rock, forming embryo dunes. Over time, vegetation such as marram grass stabilises the sand dunes forming foredunes. As the vegetation around the foredunes decomposes nutrients are released and soil begins to form. A wider range of plants are then able to colonise the dunes.
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