MC6: Atriplex prostrata-Beta vulgaris ssp. maritima sea-bird cliff community: Atriplici-Betetum maritimae J.-M. & J. Géhu 1969

Summary

Synonymy

Atriplicetum Gillham 1953; Ornithocoprophilous vegetation Gillham 1956b p.p.; Lavateretum arboreae J.-M. & J. Géhu 1961; Beta maritima – sociatie Beeftink 1962; Atriplici-Betetum perennis J.-M. & J. Géhu 1969; Beto-Tripleurospermetum maritimi Malloch 1970; Herring gull colony vegetation Sobey & Ken worthy 1979 p.p.

Constant species

Atriplex prostrata agg., Beta vulgaris ssp. maritima, Festuca rubra, Matricaria maritima.

Physiognomy

The Atriplici-Betetum is very variable in its floristics and appearance. Usually one or more of Atriplex prostata agg. (including A. glabriuscula and A. babingtonii: Aellen 1964), Beta vulgar is ssp. maritima and Lavatera arborea dominate in an open or closed, often scruffy, cover with sometimes abundant Matricaria maritima. Festuca rubra, Spergularia rupicola, Armeria maritima and Dactylis glomerata occur frequently in isolated but often vigorous fragments of crevice vegetation or maritime sward. Various species characteristic of open disturbed places, such as Polygonum aviculare agg. and Rumex crispus, may be prominent on the sometimes extensive areas of bare ground. There may be a marked seasonal variation in the vegetation with a dramatic spring growth of overwintered Cochlearia officinalis (or C. danica: Gillham 1953) being succeeded by A. prostrata.

Habitat

The community is most characteristic of rocky coastal sites where there is a combination of high maritime influence and intense disturbance by sea-birds, notably gulls (Larus spp.), razorbill (Alca torda) and guillemot (Uria aalge). Essentially similar mixtures of Atriplex spp. and Beta can also be found on strandline debris in sandy and shingle foreshores.