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Sand dune summary guidance for changing states
It is important to understand the sand dune dynamics before taking any decision
to intervene by way of management or restoration. There are many factors
influencing this dynamic all of which push the dune into a more,
or less stable state. Taking these factors into account three principle states
for the sand dune habitat have been identified, based on the degree of sand
mobility. These are shown below:
In order to help define the options when considering
moving between the three states an attempt has been made above to set a range
for the coverage of bare sand within the dune system. These figures* are only
meant to provide a very broad indication of the nature of dune mobility on a
whole site basis. Moving from Erosional (State
1) to Open/Semi-mobile (State
2) is approached in two ways:
- Preventing sand drift by the the introduction of physical
structures into the dune system;
- Helping to re-establish vegetation.
| Guidance: The methods appropriate to restoration can and are often
used in combination. However, it is helpful to consider their use separately
in the first instance. Returning over stable sand dune (State
3) to a more dynamic Open/Semi-mobile (State
2) forms requires the removal of overgrown vegetation including
scrub and by removing forestry plantations (State
3 - State 2). |
Caveat: At any one time all three states may exist on one dune system.
Movement between them (indicated by the blue arrows) can be achieved by influencing
the dynamic
of the sand dune surface. Maintaining
State 2 which can include a range of dynamic sand dune forms could
be considered to be the most advantageous from a nature conservation point of
view, and may be the preferred option.
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