AB.J4U1 Baltic aphotic sand dominated by meiofauna


Author                                     

HELCOM RED LIST Biotope Expert Team

Textual description 

Baltic aphotic zone bottoms 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. No macrocommunity present. Meiofauna constitutes at least 50% of the present biomass.

PHYSICAL ENVIRONMENT

Substrate is sand. Appears in all wave exposure classes.

Characteristic species        

Oligochaeta, Ostracoda, Nematoda, Copepoda

MAPPING ADVISE

In the Gulf of Bothnia nectobenthic Mysidae can be associated with the biotope, Mysidae can also appear in benthic grab-samples.

Quality descriptors

Diversity, abundance and biomass of fauna

Anthropogenic threats

Eutrophication

Correspondence with other classification systems               

HELCOM 1998:

2.5 Sandy bottoms

2.5.1 Aphotic zone

EUNIS 2012:

A5 Sublittoral sediment

A5.2 Sublittoral sand

A5.27 Deep circalittoral sand

A5.273 Baltic sandy bottoms of the aphotic zone

http://eunis.eea.europa.eu/habitats/2620

 Publications

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