AA.J1E Baltic photic sand characterized by epibenthic bivalves


HELCOM RED LIST Biotope Expert Team

Textual description            

Baltic photic bottoms with at least 90 % coverage of sand. Sand has less than 20 % of mud/silt/clay fraction (<63 µm), and the proportion of sand (grain size 0.063–2 mm) exceeds 70% of the combined gravel and sand fraction.  Sessile/semi-sessile epibenthic bivalves cover at least 10 % of the seabed  and more than other perennial attached erect groups.

Physical environment       

Substrate is sand. Appears in high energy exposure areas.

Characteristic species        

Mytilus spp.

Quality descriptors             

Diversity, abundance and biomass of fauna associated with the mussel beds.

Geographic range               

Whole Baltic Sea

Anthropogenic threats     

Eutrophication through increased siltation

Correspondence with other classification systems               

HELCOM 1998:
2.5 Sandy bottoms

2.5.2 Sublittoral photic zone Level bottoms with little or no macrophyte vegetation

EUNIS 2012:

A5 Sublittoral sediment

A5.2 Sublittoral sand

A5.21 Sublittoral sand in low or reduced salinity

A5.211 Baltic level sandy bottoms of the infralittoral photic zone with little or no macrophyte vegetation