Table 2 Communities based on the cluster analysis (labelled with roman numerals), location features (exposure of the shore; vertical zone) and communities based on the inverse analysis; these communities were named after characteristic and dominant species restricted to a specific community (short names of the communities are in bold)
From: Community composition of the rocky intertidal at Helgoland (German Bight, North Sea)
Communities based on cluster analysis | Location features | Communities based on inverse analysis | Biotope name according to Bartsch and Tittley (2004) | |
|---|---|---|---|---|
Exposure | Zone | |||
Community I | Semi-exposed | High intertidal | Ulva spp. | Enteromorpha spp. on freshwater-influenced and/or unstable upper eulittoral rock |
Community II | Semi-exposed | Mid intertidal | Mytilusedulis–Littorinalittorea–Ralfsia verrucosa | Mytilus edulis and Fucusvesiculosus on moderately exposed mid eulittoral rock |
Community III | Semi-exposed to exposed | Mid to low intertidal | Corallina officinalis– Fucus serratus | Corallina officinalis, coralline crusts and brown seaweeds in shallow eulittoral rockpools Dense Fucus serratus on moderately exposed to very sheltered full salinity lower eulittoral rock Fucus serratus and red seaweeds on moderately exposed lower eulittoral rock Mastocarpus stellatus and Chondrus crispus on very exposed to moderately exposed lower eulittoral rock |
Community IV | Sheltered | Mid to low intertidal (horizontal) | Cryptosula pallasiana–Dynamena pumila–Ascophyllumnodosum | Ascophyllum nodosum on very sheltered mid eulittoral rock |
Community V | Semi-exposed to exposed | Low intertidal | Rhodothamniellafloridula–tube-building polychaetes–Ulva lactuca | Rhodothamniellafloridula on sand-scoured lower eulittoral rock |
Community VI | Sheltered | High intertidal (vertical) | Balanus spp.–Fucus spiralis–Porphyra spp. | Semibalanus balanoides, Patella vulgata and Littorina spp. on exposed to moderately exposed or vertical sheltered eulittoral rock |