AA.J1S3 Baltic muddy sediment dominated by Vaucheria spp.


HELCOM RED LIST Biotope Expert Team

Textual description            

Baltic bottoms in the photic zone with at least 90 % coverage of muddy sediment. The sediment must contain at least 20 % of mud, silt or clay (grain size less than 63 ┬Ám). Annual algae cover at least 10 % of the seabed, while all other vegetation covers less than 10 %. Of the annual algae, Vaucheria spp. constitutes at least 50 % of the biovolume.

Physical environment       

Salinity range: <7 psu; Exposure range: sheltered; Depth range: photic zone down to about 7 meters.

Characteristic species        

Vaucheria spp.

Geographic range               

From southern Baltic Sea to northern Bothnian Bay and eastern Gulf of Finland

Correspondence with other classification systems               

HELCOM 1998:

2.7 Muddy bottoms

2.7.2 Sublittoral photic zone Dominated by macrophyte vegetation


EUNIS 2012:

A5 Sublittoral sediment

A5.5 Sublittoral macrophyte-dominated sediment