AA.M1B2 Baltic photic mixed substrate dominated by Zannichellia spp. and/or Ruppia spp. and/or Zostera noltii


HELCOM RED LIST Biotope Expert Team

Textual description 

Baltic bottoms in the photic zone with more than 10 %, but less than 90 % coverage of both hard and soft substrata. Submerged rooted plants cover least 10 % of the seabed and more than other perennial attached erect groups. Out of the submerged rooted plants, Zannichellia spp. and/or Ruppia spp. and/or Zostera noltii constitute at least 50 % of the biovolume.

Physical environment       

Salinity range: low to moderate; Exposure range: low to moderate; Depth range: photic zone from about 0.1 to 4 meters.

Characteristic species        

Zannichellia palustris, Ruppia maritime, Zostera noltii

Quality descriptors

Lower limit of vegetation, amount of epiphytic algae


Whole Baltic Sea



Correspondence with other classification systems               

HELCOM 1998:

2.8 Mixed sediment bottoms

2.8.2 Sublittoral photic zone Dominated by macrophyte vegetation

EUNIS 2012:

A5 Sublittoral sediment

A5.5 Sublittoral macrophyte-dominated sediment

A5.53 Sublittoral seagrass beds

A5.534 : [Ruppia] and [Zannichellia] communities