Red List habitat classification > RL - Marine habitats > RLMED - Mediterranean > MEDA2.42 Communities of Mediterranean mediolittoral mixed sediment

Communities of Mediterranean mediolittoral mixed sediment

Quick facts

Red List habitat type code MEDA2.42
Threat status
Europe Data Deficient
EU Data Deficient
Relation to
Source European Red List habitat factsheet
European Red List of habitats reports
European Red List of habitats (Excel table)

Summary

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.

Indicators of quality:

Both biotic and abiotic indicators have been used to describe marine habitat quality. These include: the presence of characteristic species as well as those which are sensitive to the pressures the habitat may face; water quality parameters; levels of exposure to particular pressure, and more integrated indices which describe habitat structure and function, such as trophic index, or successional stages of development in habitats that have a natural cycle of change over time.

There are no commonly agreed indicators of quality for this habitat, although particular parameters may have been set in certain situations, e.g. protected features within Natura 2000 sites, where reference values have been determined and applied on a location-specific basis. 

Characteristic species
For full habitat description, please download the habitat factsheet.

Threat status

Synthesis of Red List assessment

Approximately two-thirds of the Mediterranean coastline is currently urbanized, and in the most industrial regions this increases to 75%. This pressure is predicted to continue and although it has resulted in declines in quantity and quality of this habitat, the decline cannot be quantified.
This habitat is widespread throughout the Mediterranean Sea, with a large EOO and AOO, and therefore it qualifies as Least Concern under Criterion B, however because of lack of information on trends it has been assessed as Data Deficient for both the EU 28 and EU 28+.
EU
Red List Category Red List Criteria
Data Deficient -
Europe
Red List Category Red List Criteria
Data Deficient -

Confidence in the assessment

low
Red List of habitat categories and criteria descriptions

Pressures and threats

  • Agriculture
    • Use of biocides, hormones and chemicals
    • Fertilisation
  • Urbanisation, residential and commercial development
    • Urbanised areas, human habitation
    • Industrial or commercial areas
    • Discharges
  • Pollution
    • Pollution to surface waters (limnic, terrestrial, marine & brackish)
    • Nutrient enrichment (N, P, organic matter)
    • Marine water pollution
    • Soil pollution and solid waste (excluding discharges)

Habitat restoration potential

Unknown.

Trends in extent

Average current trend in quantity

Decreasing Decreasing
EU28 EU28+

Trends in quality

Average current trend in quality

Decreasing Decreasing
EU28 EU28+

Conservation and management needs

There are various legal provisions and policies which relate to this habitat such as the ICZM Protocol of the Barcelona Convention. Beneficial measures include improving water quality and both direct and indirect effects of coastal development. Direct engagement of stakeholder in the planning of the management process, analysis of social and economic costs and benefits of different management options will be essential to the successful implementation of conservation actions.

List of conservation and management needs

  • Measures related to wetland, freshwater and coastal habitats
    • Restoring/Improving water quality
  • Measures related to spatial planning
    • Establish protected areas/sites
    • Legal protection of habitats and species
    • Manage landscape features
  • Measures related to urban areas, industry, energy and transport
    • Urban and industrial waste management
    • Specific management of traffic and energy transport systems
    • Managing marine traffic
  • Measures related to special resouce use
    • Regulating/Managing exploitation of natural resources on sea

Distribution

For each habitat a distribution map was produced from a wide variety of sources indicating known and potential occurrences of the habitat in 10x10 km grids within Europe. Occurrences in grid cells were given in two classes: actual distribution from relatively reliable sources (surveys, expert knowledge), and potential distribution based on models or less reliable indicators. Please download the fact sheet to see the map.

Geographic occurrence and trends

Seas Present or presence uncertain Current area of habitat (Km2) Recent trend in quantity (last 50 years) Recent trend in quality (last 50 years)
Adriatic Sea Present Unknown Decreasing Decreasing
Aegian-Levantine Sea
Ionian Sea and the Central Mediterranean Sea
Western Mediterranean Sea

Extent of Occurrence, Area of Occupancy and habitat area

Extent of Occurrence (EOO) (Km2) Area of Occupancy (AOO) Current estimated Total Area Comment
EU28 928,625 710 Unknown EOO and AOO have been calculated on the available data. Although this data set is known to be incomplete the figures exceed the thresholds for threatened status.
EU28+ >710 Unknown EOO and AOO have been calculated on the available data. Although this data set is known to be incomplete the figures exceed the thresholds for threatened status.
AOO = the area occupied by a habitat measured in number of 10x10 km grid cells.
EOO = the area (km2) of the envelope around all occurrences of a habitat (calculated by a minimum convex polygon).

Characteristic species

The full list of characteristic species and genus are available above from the Summary. The species available in the EUNIS database are shown here.
Invertebrates Abra nitida
Invertebrates Aora gracilis
Invertebrates Aphelochaeta marioni
Invertebrates Capitella capitata
Invertebrates Cerastoderma edule
Invertebrates Cirriformia tentaculata
Invertebrates Corophium volutator
Invertebrates Melita palmata
Invertebrates Microprotopus maculatus
Invertebrates Pygospio elegans
Invertebrates Sphaerosyllis taylori
Invertebrates Tubificoides pseudogaster
Species scientific name English common name Species group
Abra nitida Invertebrates
Aora gracilis Invertebrates
Aphelochaeta marioni Invertebrates
Capitella capitata Invertebrates
Cerastoderma edule Invertebrates
Cirriformia tentaculata Invertebrates
Corophium volutator Invertebrates
Melita palmata Invertebrates
Microprotopus maculatus Invertebrates
Pygospio elegans Invertebrates
Sphaerosyllis taylori Invertebrates
Tubificoides pseudogaster Invertebrates

Vegetation types

Relation to vegetation types (syntaxa)

Not available

Other classifications

Not available
European Environment Agency (EEA)
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