AA.B Baltic photic hard clay


HELCOM RED LIST Biotope Expert Team

Textual description

Baltic bottoms in the photic zone with at least 90 % coverage of hard clay.

Physical environment

Salinity range: All; Exposure range: All; Depth range: Photic zone

Characteristic species

Barnea candida, Mytilus spp.

Mapping advise (habitat delineation, identification, similar types)

Photic zone bottoms of hard clay

Quality descriptors

Loose sediment covering the seabed 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:
2.3 Hard clay bottoms

2.3.2 Sublittoral photic zone