AA.I2T Baltic photic coarse sediment characterized by sparse epibenthic macrocommunity


HELCOM RED LIST Biotope Expert Team

Textual description            

Baltic photic bottoms with at least 90 % coverage of coarse sediment. Coarse sediment has less than 20 % of mud/silt/clay fraction (<63 µm), and the proportion of gravel and pebbles (grain size 2–63 mm) exceeds 30% of the combined gravel and sand fraction. Sessile/semi-sessile epifauna and flora is present but below 10 % coverage.

Physical environment       

Substrate is coarse sediment. Appears in high energy exposure areas.

Characteristic species        

Mytilus spp, Hydroids, Amphibalanus improvisus

Quality descriptors             

Diversity, abundance and biomass of fauna.

Geographic range               

Whole Baltic Sea  

Correspondence with other classification systems               

HELCOM 1998:
2.4 Gravel bottoms

2.4.2 Sublittoral photic zone Level bottoms with little or no macrophytevegetation

EUNIS 2012:

A5 Sublittoral sediment

A5.1 Sublittoral coarse sediment

A5.11 Infralittoral coarse sediment in low or reduced salinity

A5.111 : Baltic level gravel bottoms of the infralittoral photic zone with little or no macrophyte vegetation