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Shingle - Summary of States
Shingle beaches
Shingle beaches and structures erode and accrete at their seaward margin. On
narrow fringing beaches, periodic movement occurs in response to tidal movement
and storms. The former help to move the beach material along the shore, the
latter may force major repositioning of the beach often in a landward direction.
Two states can be described for shingle beaches namely:
Whilst these state may exist in a dynamic equilibrium it is often the case
that erosion predominates in areas where shingle has been extracted from reserves
offshore or from the beach itself. This not only results in the loss of ephemeral
vegetated shingle communities, but can also have adverse consequences for the
sea defence capability of the beach.
Shingle structures
A very different situation arise where more substantial structures exist and
both ephemeral and stable shingle surfaces are present. Here the issues surrounding
restoration are largely concerned with restoring stable surface shingle, together
with its vegetation and associated animal interests. Although the issues surrounding
restoration of the surface shingle can be linked to the re-establishment of
shingle dynamics, the methods of restoration are considered separately. Thus
two states are identified:
Caveat: At the seaward edge of a shingle beach erosion and accretion
are the norm. They can exist in a dynamic equilibrium and develop with or without
ephemeral vegetation. This state is not considered as a separate type but is
included in the erosional and accretional forms of State 1 and State 2, respectively.
Comment: Links to the values of these states are provided via the
individual State descriptions.
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