MA4-5 - Sédiment hétérogène du supra- et du médiolittoral en Méditerranée (EUNIS 2022)

MA4-5 - Sédiment hétérogène du supra- et du médiolittoral en Méditerranée

Mediterranean littoral mixed sediment

MA4-2 - Sédiment hétérogène du supra- et du médiolittoral en Atlantique

Classification des habitats EUNIS 2022

Descriptif de l'habitat

Mediterranean shores of mixed sediments range from muds with gravel and sand components to mixed sediments with pebbles, gravels, sands and mud in more even proportions. By definition, mixed sediments are poorly sorted. It is likely that there are broad transition areas between areas of mudflat or sandy mudflat, and mixed sediment biotopes where the sediment consists mainly of mud but has significant proportions of gravel and sand mixed in. Gravel mud may occur in patches on mudflats. Similarly, there is no easily defined boundary between areas of mixed sediment with stable cobbles and boulders, and boulder fields which fall into the rocky shore category. Stable large cobbles or boulders may be present which support epibiota such as fucoids and green seaweeds which are more commonly found on rocky and boulder
shores.
Mixed sediments which are predominantly muddy tend to support infaunal communities which are similar to those of mud and sandy mud shores. Habitats with sheltered gravel sandy mud, which are subject to reduced salinity, mainly on the mid and lower shore, may have abundant communities of polychaetes.
Characteristic species: Polychaetes: Aphelochaeta marioni, Capitella capitata, Cirriformia tentaculata ,Sphaerosyllis taylori, Pygospio elegans; bivalves: Cerastoderma edule, Abra nitida; oligochaetes:Tubificoides pseudogaster; crustaceans: Aora gracilis, Melita palmata, Microprotopus maculatus, Corophium volutator.

Bibliographie

European Topic Centre on Biological Diversity 2022. EUNIS marine habitat classification 2022 including crosswalks. Table Excel. (Source)