AA.J3L Baltic photic sand characterized by infaunal 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.  No macrovegetation or epibenthic macrofauna. Biomass of infaunal bivalves is at least 10 % and highest of the groups infaunal bivalves/polychaetes/crustaceans/insect larvae.

Physical environment       

Substrate is sand. Appears in high energy exposure areas.

Characteristic species        

Macoma balthica Arctica islandica,Cerastoderma spp., Mya arenaria, Astarte borealis, Macoma calcarea, Mya truncata, Astarte spp., Spisula spp., Chamelea gallina

Quality descriptors             

Diversity, abundance and biomass of fauna.

Geographic range               

Whole Baltic Sea

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