Sand dunes occur when sediment-carrying wind drops its load where obstructions block its path and in this manner, sand accumulates. This creates sand mounds or ridges. Obstructions include vegetation or rocks. For most dunes, the profile is non-symmetrical where the wind-sheltered slope is steeper than the windward slope, which is more gently inclined.

There are several types of dune, which form consistent patterns. Wind

direction and velocity, sand availability and vegetation present influence the form and size of dunes.

Research explains different threats faced by dunal ecosystems including the following:

Anthropogenic Pressures such as trampling (on a local scale) to sea-level rise (global scale). For the latter, when combined with storms and adverse weather conditions would result in erosion and severe habitat loss.

Population growth and human settlements close to the coast. Other anthropogenic activities such as pollution, mining and

sand transport increases the subjectivity of sandy shores to erosion.

Structures or activities which inhibit/alter natural transport of sand or alter the budget of sand also lead to erosion.

Positive activities, such as beach cleaning or ecotourism can also influence coastal ecosystems negatively.

20.5m

14.8m 26.5m

3.65m

25.3m

31.4m