HELCOM RED LIST Biotope Expert Team
Baltic bottoms in the aphotic zone 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. Macroscopic infauna present, no epibenthic macrofauna.
Salinity range: all; Exposure range: moderate to high; Depth range: aphotic zone
Aphotic zone areas with coarse sediment such as gravel. Coarse sediment has less than 20 % of mud/silt/clay fraction (<63 µm), and at least 30 % of grain size 2–63 mm. Macroscopic infauna present, no epibenthic macrofauna.
Soft sediment covering the coarse sediment will decrease the quality.
Whole Baltic Sea
Silting caused by eutrophication, dredging spoil deposition etc.
2.4 Gravel bottoms
2.4.1 Aphotic zone
A5 Sublittoral sediment
A5.1 Sublittoral coarse sediment
A5.11 Infralittoral coarse sediment in low or reduced salinity
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