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Natural restoration of shingle vegetation
Regeneration of shingle beach vegetation following disturbance is a naturally
slow process. Because of the exposure to waves and storms the vegetation which
develops is ephemeral.
A few species such as Crambe maritima (a
perennial) and Glaucium flavum (a biennial)
can withstand some disturbance and other species such as Honckenya
peploides are tolerant of seawater or salt spray. Once the level of the
shingle surface is moved above the direct influence of storm waves more stable
communities occur. These depend not only on having a stable substrate, but also
on the development of water retaining properties in the shingle matrix. This
builds up over time as organic and other material is brought into the system.
An important requirement for restoring vegetation on shingle beaches is a natural
beach profile. The main features are shown in the Table below:
| Feature |
Size/range |
Comment |
| Slope |
1:100 - 1:15 |
Natural range |
| Sediment size |
2mm - 200mm |
Range for shingle (Randall 1977a) |
| Sand content |
10 - 20% sand content |
Best for vegetation establishment (Walmsley
& Davy 2001) |
| Guidance: Robust species such as Suaeda
vera, a shrubby species because of its "power of rejuvenation"
and ability to arrest the movement of shingle was considered to be potentially
valuable in helping to restore stability to shingle shores (Oliver
& Salisbury 1913). The same species together with Crambe
maritima, with its deep tap-root were both also considered suitable
as an aid to stabilisation (Carey & Oliver
1918). However despite these early reports little interest has developed
over the intervening years. In effect given the forces involved when shingle
which lies at the upper limits of size is moved it seems unlikely that significant
and lasting stabilising effects can be achieved by plant species alone.
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References
Carey, A.E. & Oliver, F.W.
1918.
Tidal Lands: a Study in Shoreline Problems. Blackie and Son Limited, London, 284 pp.
Oliver, F.W. & Salisbury, E.J.
1913.
Vegetation and Mobile Ground as Illustrated by Suaeda Fruticosa on Shingle.
Journal of Applied Ecology, 1/4., 249-272.
Abstract...
Randall, R.E.
1977a.
Shingle foreshore.
In: The Coastline, ed.Barnes, R.S.K.John Wiley & Sons, Chichester, 49-61.
Walmsley, C.A. & Davy, A.J.
2001.
Habitat creation and restoration of damaged shingle communities.
In: Ecology & Geomorphology of Coastal Shingle, eds.Packham, J.R., Randall, R.E., Barnes, R.S.K. & Neal, A.Westbury Academic and Scientific Publishing, 409-420.
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