Latest news from the IMPACT network #19

@ Andromède Océanologie

Human activities induce significant pressures on the marine environment, and coastal ecosystems in particular. The IMPACT network, operated since 2013 by Andromède océanologie with the support of the Rhône Méditerranée et Corse Water Agency, models and maps the main anthropogenic pressures on French Mediterranean coastal water bodies.

Destruction d’un herbier de posidonie avec une ancre de bateau. @Andromède Océanologie.

–> In 2015, ten anthropogenic pressures were modeled according to distance from the source of pressure and its intensity:

  • Urbanization
  • Fishing
  • Boat mooring
  • Aquaculture
  • Agriculture
  • Population
  • Industrial effluents
  • Coastal development
  • Urban discharges
  • Erosion/Coastal degradation

This work led to a first scientific publication (Holon et al. 2015).

–> In 2018, three pressures were added:

  • Small yacht anchorage
  • Seaside tourism
  • River pollution

And the effect of each pressure on the Posidonia meadow was analyzed (Holon et al. 2018).
Decline index: % alive / % alive + % dead

–> In 2019, a detailed analysis of anchoring pressure from pleasure boating was published in the cahier de la surveillance n°15. This study provided input for the discussions that led to the publication of decree n°123/2019 banning the anchoring of large units (+ 24 m) in the Posidonia meadow.

Wishing to go even further in understanding the links between anthropogenic pressures and the status of coastal ecosystems, Andromède océanologie has committed itself in 2021 to a thesis project entitled: “An innovative approach to the study and management of anthropogenic pressures and their impacts on French Mediterranean coastal marine ecosystems using Big data”.

More specifically, this thesis studies pressures from anchoring and urban discharges, and has already led to the publication of an initial work assessing the effectiveness of regulations banning anchoring in the seagrass beds for large vessels (Bockel et al. 2023). Several studies on the impact of anchoring small vessels (< 24 m) and urban discharges are currently underway.

Mapping of anthropogenic pressures from the IMPACT project is now available for free download on the SEANOE platform.


Thomas Bockel, Andromède Océanologie