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Shingle structures - State 4, Disturbed/Excavated to State
3, Vegetated
This change in states is principally concerned with the restoration of 'natural'
vegetation and is thus related to conservation needs. Restoring vegetated shingle
can be broken down into two elements, which depend on:
- whether the surface is dry, i.e. excavation is above the water table;
- the shingle surface is at or near the water table.
Restoring the physical shingle structure (ridges and lows) is a precursor
to re-establishing vegetation, but is difficult, especially on dry well drained
shingle. The Figure below gives a summary view of the direction of the main
restoration opportunities. 
Caption:
The methods of restoring vegetation on excavated shingle surfaces that lie
above the water table depends on the amount of moisture near the disturbed shingle
surface. Hence two 'routes to restoration' for vegetation on shingle surfaces
have been identified one for 'dry'
shingle and one for 'damp'
shingle.
| General guidance: Such information as exists from a small number
of sites suggests that left to their own devices vegetation can recolonise
shallow excavations/disturbance of shingle. Time, and freedom from disturbance
are key factors. The greater the moisture retaining properties of the surface
layer the more rapid and complete is the development of vegetation. |
Comment: Shallow excavations of dry shingle can result in an overall
increase in biodiversity within a site. For a discussion of this, and other
biodiversity issues pertaining to gravel extraction from shingle structures,
see the example of Dungeness (Doody 2001
chapter 9.4.1 and Ferry 2001).The restoration
of gravel pits
on shingle structures is not a subject for this guide, but for guidance on management
see (Andrews & Kinsman 1991).
References
Andrews, J. & Kinsman, D.
1991.
Gravel Pit Restoration: Site Managers' Guide.
Royal Society for the Protection of Birds.
Doody, J.P.
2001.
Coastal Conservation and Management: an Ecological Perspective. Kluwer, Academic Publishers, Boston, USA, 306 pp.
Conservation Biology Series, 13
Ferry, B.
2001.
Vegetation of the Dungeness shingle: aspects of biodiversity.
In: Ecology & Geomorphology of Coastal Shingle, eds.Packham, J.R., Randall, R.E., Barnes, R.S.K. & Neal, A.Westbury Academic and Scientific Publishing, 224-241.
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