Dunes Lecture 12

Question 1

what are the aeolian sediment transport processes?

Answer 1

Saltation
Threshold wind speed required to entrain sediment
Very fine sediment more cohesive
Wet sand = more cohesive therefore requires higher wind speed

Question 2

How is an offshore wind important for coastal dune development?

Answer 2

Recirculating wind within recirculation zone, or deflected from crest may be strong enough to transport sed. from beach onto dune

Question 3

What are the main coastal dune types and where do they occur?

Answer 3

(In order of + sand and - veg)
Foredunes
Blowouts 
Parabolic 
Transgressive

Question 4

Vegetation differences?

Answer 4

Marram grass - buried

Seabuckthorn - stable environment

Question 5

What is a CA model to look at dune development and impact of climate drivers?

Answer 5

DECAL - discrete ecogeomorphic aeolian landscape model

Question 6

What is an artificial dune construction

Answer 6

Sand fences- trap sand, create new dunes, inexpensive and easy to construct