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Sand fencing
Reducing the velocity of the wind is a key element in encouraging the deposition
of sand grains and with it the establishment of vegetated sand dunes according
to a relatively well studied succession.
Where it becomes difficult for native vegetation to fulfill this role because
of excessive human activity and/or there is an urgent need for stabilisation
the role of the plants can be replaced by sand fences. These have been employed
at many sites and come in a variety of forms to accumulate sand and increase
the height and width of the dune. Porous fencing made of chestnut palings; brushwood
and other material are used. Typical configurations are shown below:
Sand fences are often used in conjunction with Ammophila
planting see for example:
Details of the type and orientation in relation to prevailing and dominant
winds (crucial to their success) are found in a number of practical guidance
notes and papers (e.g. Ranwell & Boar 1986;
Doody 1985 and for detailed discussion Scottish
Natural Heritage Beach
Erosion Management Guide.). A comparison between methods employed
in New Jersey (USA) and Holland has been made (Nordstrom
& Arens 1998) .
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Guidance: The geomorphological context for dune development is
an important issue in deciding on the appropriate orientation, frequency
and location of fences. This can only be obtained by reference to the
prevailing conditions on the sites itself though scientific studies texts
can provide important background information (e.g. Pye
& Psoar 1990).
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References
Doody, J.P.
1985.
Sand Dunes and their Management.
Focus on nature conservation, 13
NCC, Peterborough.
Nordstrom, K.F. & Arens, S.M.
1998.
The role of human actions in evolution and management of foredunes in the Netherlands and New Jersey, USA.
Journal of Coastal Conservation, 4/2., 169-180.
Pye, K. & Psoar, H.
1990.
Aeolian Sand and Sand Dunes. Unwin Hyman Ltd., London, 396 pp.
Ranwell, D.S. & Boar, R.
1986.
Coast Dune Management Guide. Institute of Terrestrial Ecology, NERC, 105 pp.
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