Date (Creation)

2025-01-17

Date (Publication)

2025-05-17

Identifier

https://sextant.ifremer.fr/record/50bc62bb-a226-445d-a2b9-b45c59eaaec1

Credit

Ifremer

Thèmes Sextant

• /Biological Environment/Habitats

GEMET - INSPIRE themes, version 1.0

• Habitats and biotopes

DCSMM : Descripteurs

• D1: Coastal benthic habitats

Thématiques - SIMM

• /Environmental Status/Habitats
• /Environmental Status/Species

Use limitation

CC-BY (Creative Commons - Attribution)

Access constraints

Other restrictions

Use constraints

Copyright

Other constraints

We do our best to ensure that the data is complete, accurate and useful. However, because the processing required to generate the data is complex, we cannot be liable for omissions or inaccuracies. The data and any related materials contained therein are provided “as is”, without warranty of any kind, either expressed or implied, including but not limited to, fitness for a particular purpose, non-interference, system integration, or non-infringement. The entire risk of use of the data shall be with the user.

Aggregate Datasetindentifier

e4521877-e3a0-4dbf-867e-6a339e1c957f

Association Type

Cross reference

Aggregate Datasetindentifier

b0a85bec-a8a7-40f8-ae83-b4302328c5f4

Association Type

Cross reference

Aggregate Datasetindentifier

0e50beb8-555d-43df-aac6-e23a7f7ffdb0

Association Type

Cross reference

Spatial representation type

grid Grid

Distance

0.04  degree

Metadata language

English

Character set

utf8 UTF8

Topic category

• Oceans
• Environment

Begin date

2016-01-01

End date

2023-12-31

Reference system identifier

EPSG / WGS 84 (EPSG:4326) / 8.6

Number of dimensions

2

Dimension name

Vertical

Dimension size

355200

Dimension name

Column

Cell geometry

Area

Transformation parameter availability

No

Distribution format

• ( )

OnLine resource

IFREMER SIH (2023).Sous-divisions GSA CGPM/GFCM (version SIH). IFREMER SIH ( WWW:LINK )

Protocol

COPYFILE

Name

merge_bioregion.tif

Description

Megabenthic bioregions in the Mediterranean

Function

Download

OnLine resource

merge_bioregion ( OGC:WMS )

Mediterranean bioregions of megabenthic communities

OnLine resource

Digital Object Identifier (DOI) ( DOI )

Hierarchy level

Dataset

Statement

This layer is linked to the following study: "Characterizing Soft-bottom Megabenthic Communities of the Mediterranean Continental Shelf: A Biogeographic Approach", 2025, Jade Millot, Sandrine Vaz, Tarek Hattab, Christopher J. Smith, Carlos Dominguez-Carrió, Beatriz Guijarro, Grégoire Certain, Vasilis Gerovasileiou, Vincent Georges, Caterina Stamouli, Michele Casini, Chiara Manfredi, Emanuela Fanelli, Germana Garofalo, Marie-Claire Fabri, Daniela Massi, Angélique Jadaud, Adriana Profeta, Pierluigi Carbonara, Evgenia Lefkaditou, Slavica Petović, Athanasios Evangelopoulos, Nikolaos Kamidis, Ioannis Thasitis, Jurgen Mifsud, Kelly Camilleri, Valentina Lauria. This study is submitted but not yet published.

Description

Records of megabenthic invertebrates were extracted from the MEDITS (MEDiterranean International Trawl Survey) database from 2016 to 2021 (2023 for the French data). Rare taxa were excluded by applying a taxonomic filter : taxa were grouped at a higher taxonomic level if they were recorded in less than 60% of the years per GSA (Geographical Sub-Areas), or if they accounted for less than 5% of all stations per GSA and year. Data were split per sub-basin (Western Mediterranean, Central Mediterranean, Adriatic Sea, Aegean Sea). Biomass data (g/km2) were log-transformed (log(x+1) and standardized applying an Hellinger-transformation. Then, a PCA was applied on each dataset to remove noise and only axes representing at least 2% of the total variance were retained.

Rationale

Prepare datasets of megabenthic records per sub-basin.

Description

K-means clustering was applied on PCA outputs, per sub-basin, to group similar MEDITS trawl stations based on their composition in megabenthic communities.

Rationale

Obtain clusters of MEDITS trawl stations per sub-basin.

Description

A Random Forest (RF) algorithm was used to predict the distribution of each cluster (factor-type variable) in function of environmental variables. RFs were calibrated on 80% of the dataset while the remaining 20% was used to evaluate its performance.

Predicted areas of each cluster defined by the RF models and characterized by distinct megabenthic invertebrate communities defined the bioregions of the study.

Rationale

Predict the distribution of the megabenthic bioregions per sub-basin.

Description

Bioregions identified in the four different sub-basins were finally merged in a final map.

Rationale

Obtain a map of the full bioregionalization of the Mediterranean soft-bottom above 1000m.

File identifier

50bc62bb-a226-445d-a2b9-b45c59eaaec1 XML

Metadata language

English

Character set

UTF8

Hierarchy level

Dataset

Date stamp

2025-05-16T14:40:36.226615Z

Metadata standard name

ISO 19115-3 - SEXTANT

Metadata standard version

1.0