Biodiversity & Conservation

To assess the sensitivity of the biotope, the sensitivity of component species is reviewed. Those species that are considered to be particularly indicative of the sensitivity of the biotope, and for which research has been undertaken in detail are shown below (see selection criteria). The biology of other component species of the biotope is also taken into account wherever information is known to the researcher.

The bivalves Macoma balthica and Abra alba are particularly characteristic of the biotope but owing to their deposit feeding activity and the densities at which they may occur (> 1000 per m²) these species have been given key functional status. The manner in which such bivalves intensively rework the uppermost few centimetres of the sediment produces a fluid faecal-rich layer, the physical instability of which tends to inhibit the development of a benthic suspension feeding community or relatively sessile epifauna (see review by Rhoads & Young, 1970). Consequently, the feeding activity of the bivalves maintains community structure and function. Other infaunal burrowing species such as Echinocardium cordatum are considered to be important functional species because their deeper burrows enhance the oxygenation of the substratum and enhance the survival of a variety of small species (Pearson & Rosenberg, 1978). The presence of the polychaete Lagis koreni is considered important for the classification of the biotope. The brown shrimp, Crangon crangon is an important other species, whilst it may not be highly faithful to the biotope, its presence does however affect the sensitivity of the biotope as it is the target of a commercial fishery.

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