The rasters correspond to the prediction uncertainties associted with the production of Mediterranean bioregions of megabenthic communities

These rasters correspond to the environmental predictors used in the production of Mediterranean bioregions of megabenthic communities

The raster corresponds to the predicted Mediterranean bioregions of megabenthic communities.

The shapefile corresponds to areas where predicted bioregions were extrapolated for lack of benthic in-situ observations.

Sediment average grain size in the European North-East Atlantic and Mediterranean waters was generated from Euseamap 2023 sediment categories. This rough granulometry estimate may be used for habitat models at meso- and large scale.

Process-driven seafloor habitat sensitivity (PDS) has been defined from the method developed by Kostylev and Hannah (2007), which takes into account physical disturbances and food availability as structuring factors for benthic communities. It is a conceptual model, relating species’ life history traits to environmental properties. Physical environment maps have been converted into a map of benthic habitat types, each supporting species communities with specific sensitivity to human pressures. It is based on two axes of selected environmental forces. The "Disturbance" (Dist) axis reflects the magnitude of change (destruction) of habitats (i.e. the stability through time of habitats), only due to natural processes influencing the seabed and which are responsible for the selection of life history traits. The "Scope for Growth" (SfG) axis takes into account environmental stresses inducing a physiological cost to organisms and limiting their growth and reproduction potential. This axis estimates the remaining energy available for growth and reproduction of a species (the energy spent on adapting itself to the environment being already taken into account). It can be related to the metabolic theory of the ecology. The process-driven sensitivity (PDS) can be seen as a risk map that combines the two previous axes and reflects the main ecological characteristics of the benthic habitats regarding natural processes. Areas with low disturbance are areas with a naturally low reworking of the sediment, allowing the establishment of a rich sessile epifauna community, with K-strategy species. Areas with low SfG means that the environmental factors, even though there are not limiting, are in lower values, i.e. that it imposes a cost for species to live. In areas combining low disturbance and low SfG, big suspension-feeder species with long life and slow growth can often be found: these species are more vulnerable in case of added disturbance.

Sediment average grain size in French Mediterranean waters was generated from sediment categories. This rough granulometry estimate may be used for habitat models at meso- and large scale.

Sediment average grain size in the Mediterranean was generated from sediment categories. This rough granulometry estimate may be used for habitat models at meso- and large scale.

Process-driven seafloor habitat sensitivity (PDS) has been defined from the method developed by Kostylev and Hannah (2007), which takes into account physical disturbances and food availability as structuring factors for benthic communities. It is a conceptual model, relating species’ life history traits to environmental properties. Physical environment maps have been converted into a map of benthic habitat types, each supporting species communities with specific sensitivity to human pressures. It is based on two axes of selected environmental forces. The "Disturbance" (Dist) axis reflects the magnitude of change (destruction) of habitats (i.e. the stability through time of habitats), only due to natural processes influencing the seabed and which are responsible for the selection of life history traits. The "Scope for Growth" (SfG) axis takes into account environmental stresses inducing a physiological cost to organisms and limiting their growth and reproduction potential. This axis estimates the remaining energy available for growth and reproduction of a species (the energy spent on adapting itself to the environment being already taken into account). It can be related to the metabolic theory of the ecology. The process-driven sensitivity (PDS) can be seen as a risk map that combines the two previous axes and reflects the main ecological characteristics of the benthic habitats regarding natural processes. Areas with low disturbance are areas with a naturally low reworking of the sediment, allowing the establishment of a rich sessile epifauna community, with K-strategy species. Areas with low SfG means that the environmental factors, even though there are not limiting, are in lower values, i.e. that it imposes a cost for species to live. In areas combining low disturbance and low SfG, big suspension-feeder species with long life and slow growth can often be found: these species are more vulnerable in case of added disturbance.

Ten Random Forest models were fitted in order to characterise the environmental niche and to predict the potential spatial distribution of Zostera marina along the French western seaboard. 3 rasters are provided: 1) Habitat suitability index (values ranging from 0 to 1 when conditions are estimated to be optimal), 2) standard deviation around the mean habitat suitability index, and 3) binary suitability estimates (0= not suitable, 1=suitable). These model estimates indicate areas where the species may occur and are overall consistent with field observations but note that these maps are model-based and do not correspond to actual field observations.