State 3 - stable coastal vegetated shingle ridges

Definition: Shingle ridges removed from the influence of storms and where the build up of fine fractions between the pebbles helps support plant establishment

The natural process of beach ridge formation can result in the development of large structures as former beaches are piled against each other. These structures may take a variety of forms depending on strength and direction of the waves, storm conditions and availability of sediment in a suitable size range. Shingle structures may enclose estuaries and embayments as a result of material being moved by long shore drift and form spits, bars and barriers. Major accumulations of successive ridges piled on shore under storm conditions can develop into cuspate forelands. Nesses and recurved spits form where there is a convergence (or divergence) of littoral drift. Cheniers are a special form of shingle which is driven onshore as a series of low shell deposits.

In the absence of human interference these all provide essentially stable surfaces on which other factors come into play, which influence the development of vegetation. The action of the waves and storms that create the ridges help sort the pebbles. Subsequently material is washed into the spaces between the pebbles and can result in sufficient water retention to facilitate plant growth. Over long periods of time stable communities develop, which can range from lichens growing directly on the pebbles (as at Orfordness), to grassland, heath and scrub (State 3, see Picture below).

Caption: Stable shingle ridges on the Culbin shingle bar, north east Scotland. As can be seen from the picture this state includes a mosaic of open and closed (low-growing grassland and heath) and scrub vegetation.

The value of this state lies in the presence of undisturbed structures (ridges and lows) and the diversity of plant and animal communities which are associated with them. This state provides geographically the widest and most diverse expression of the vegetated shingle habitat in Great Britain.