Opportunities to re-establish Coastal vegetated shingle are very limited. It is a rare community that is restricted to a few coastal areas where marine processes have produced stable shingle banks. These banks develop characteristic vegetation communities over a long time period.
General Principles
The processes involved in developing coastal vegetated shingle are poorly understood, and attempts to re-establish it are very much experimental.
Each site should be treated separately, and generic advice must be reviewed in light of local circumstances. The process of shingle bank formation and geological origin of the shingle will influence the vegetation community type that develops and its distribution. Much of the coastal shingle deposits were deposited by tidal processes that drag eroded material along the coast in a process known as long-shore drift. No two locations will have had precisely the same process.
Following minerals winning, the opportunities for re-establishing vegetated shingle are relatively slight as the water table is often breached. Opportunities may however exist on the edges of pits, and where built structures have been removed.
The simplest and most recommended means of encouraging shingle vegetation to re-establish will be to remove all plant structures and bases, particularly concrete as this is lime rich, and grade the shingle into stable forms; then leave it to its own devices. Colonisation is likely to be very slow, potentially over hundreds of years, but this should not be a deterrent. The natural development of and changes in the community during colonisation will be particularly valuable.
Long-shore drift often creates a natural land form of long shallow ridges interspersed with shallow depressions. Replicating this, related to the local land form, would provide the best topography for natural processes to colonise.
Where there is a pressing need to achieve vegetation cover, active management may be necessary, but it is here that techniques are no more than experimental, and there is no guarantee of success.
Experimental techniques for establishing vegetated shingle
Establishing broom, which is an early coloniser of shingle and the leaf litter that develops acts as a bed for other species, including important lichen communities to establish. Turfing and seeding have been used to assist the process.
Turf was moved to restore areas. Turfs of long established vegetation include substantial amounts of humus, allowing whole sections to be lifted.
Laying the turfs in a chequerboard pattern facilitates colonisation of bare shingle in between. Experiments with this have had some, albeit slow success.
Seeding of broom: seeds were planted in sand packets – 4 seeds to a packet - at around 1m spacings. In experiments at Dungeness, survival has been low – 6% after four years – but some plants are now quite substantial and lichen communities have begun to establish among them.
In general container-grown plants appear to have an advantage in establishing perennial vegetation, where a sand based medium is used with small amounts of organic matter.
Fertilising and artificial organic matter incorporation have little advantage and can be expensive. Meanwhile, control of rabbits may be necessary as some characteristic species, eg sea kale, are highly palatable. The use of the shrub Tamarisk is not recommended as it is non-native and could be invasive.
Selected experiments that have had some success include:
- Seeding with sea campion onto shingle that had been enhanced with peat free compost: plants have successfully established
- Wood sage and false oat grass vegetation translocation into shingle during the winter: although some has established there has been no spread to date.
- Planting of broom pot grown plants: this was successful where conditions stayed moist after planting.
The following was not successful
- Spreading dock seeds - failed.
The conditions on exposed shingle are hostile for plant establishment. Water availability is crucial, yet drought events are frequent on shingle ridges. Heat and cold extremes are relatively dramatic and wind exposure will readily desiccate seedlings. Therefore, restoration will always be complex.
Further reading
English Nature (2003) Living With The Sea Project; coastal vegetated shingle chapter. English Nature website (www.english-nature.org.uk)
Packham JR, Randall RE, Barnes RSK and Neal A (eds) (2001). Ecology And Geomorphology Of Coastal Shingle. Westbury Publishing Otley
Sneddon, P.E. & Randall, R.E., (1993), Coastal vegetated shingle structures of Great Britain. JNCC Peterborough.
Relevant case study
The information set out within this advisory sheet in no way constitutes legal or regulatory advice and is based on circumstances and facts as they existed at the time Nature After Minerals compiled this document. Should there be a change in circumstances or facts, then this may adversely affect any recommendations, opinions or findings contained within this document