10.9 Sand dunes

Question 1

Describe the processes responsible for the formation of beaches and sand dunes

Answer 1

• sand deposited by constructive waves to form a beach
• sand blown inland (by onshore winds) form dunes
• embryo dunes form around rocks and over time become stabilised by vegetation (such as marram grass, which has long roots to find water and hold the sand together)
• the fore dunes and yellow dunes become back dunes due to rotting vegetation making it more fertile (and more plants growing)

Question 2

Embryo dune def

Answer 2

Newly formed sand dune closest to the sea

Question 3

Marram grass def

Answer 3

Plant found in sand dunes that has long, binding roots

Question 4

Saltation def

Answer 4

Sand bounced along by the wind

Question 5

Crest def

Answer 5

Top of a sand dune

Question 6

Water table def

Answer 6

Upper horizontal limit of wet sand

Question 7

Dune slack def

Answer 7

Trough or low point in the line of dunes

Question 8

Leeward slopes def

Answer 8

Slope faces away from the wind

Question 9

Windward slope def

Answer 9

Slope faces the wind