AA.J1 Baltic photic sand characterized by macroscopic epibenthic biotic structures


HELCOM RED LIST Biotope Expert Team

Textual description

Baltic bottoms in the photic zone 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.  Coverage of macroscopic vegetation or sessile macroscopic epifauna is ≥10%.

Physical environment

Salinity range: all; Exposure range: all; Depth range: photic zone

Characteristic species

Phragmites australis, Zostera marina, Potamogeton perfoliatus, Stuckenia pectinata, Tolypella nidifica, Chara aspera, Mytilus spp., Hediste diversicolor

Mapping advise (habitat delineation, identification, similar types)

Photic zone areas with pure sand, often characterized by ripple marks. Sediment must contain less than 20 % of mud/silt/clay fraction (<63 µm), and more than 70 % of sand (grain size 0.063–2 mm ). Coverage of macroscopic vegetation or sessile macroscopic epifauna is ≥10%.

Quality descriptors

Soft sediment covering the sand will decrease the quality.

Geographic range

Whole Baltic Sea

Anthropogenic threats

Silting caused by eutrophication, dredging spoil deposition etc.

Correspondence with other classification systems

HELCOM 1998:

2.5 Sandy bottoms

2.5.2 Sublittoral photic zone

 HELCOM 2007:

Macrophyte meadows and beds

  • habitat under threat and/or in decline in all areas of occurrence: Bothnian Bay, The Quark, The Bothnian Sea, Åland Sea, Archipelago Sea, Gulf of Finland, Gulf of Riga, The Southern Baltic Proper, The Gulf of Gdansk, Bay of Mecklenburg, Kiel Bay, Little Belt, Great Belt, The Sound, Kattegat

 EUNIS 2012:

A5 Sublittoral sediment

A5.2 Sublittoral sand

A5.21 Sublittoral sand in low or reduced salinity