AA.I1A1 Baltic photic coarse sediment characterized by common reed (Phragmites australis)


Author                                     

HELCOM RED LIST Biotope Expert Team

Textual description            

Baltic bottoms in the photic 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 .Emergent vegetation covers least 10 % of the seabed and more than other perennial attached erect groups. Out of the emergent vegetation, common reed constitutes at least 50 % of the biovolume.

Physical environment       

Salinity range: <6 psu; Exposure range: moderately exposed; Depth range: photic zone down to about 2 meters.

Characteristic species        

Phragmites australis

GEOGRAPHIC RANGE

Whole Baltic Sea

Anthropogenic threats   

Decreased light penetration depth and increased sedimentation caused by eutrophication

Correspondence with other classification systems               

HELCOM 1998:

2.4 Gravel bottoms

2.4.2 Sublittoral photic zone

2.4.2.2 Level bottoms dominated by macrophyte vegetation

EUNIS 2012:

A5 Sublittoral sediment

A5.5 Sublittoral macrophyte-dominated sediment

A5.54 Angiosperm communities in reduced salinity

A5.541 Vegetation of brackish waters dominated by [Phragmites australis]

http://eunis.eea.europa.eu/habitats/1735


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