The contribution of wind-wave energy at sea bottom to the modelling of rhodolith beds distribution in an off-shore continental shelf

Abstract

The study aims to investigate the relationship between the presence of rhodolith beds and the effect on the shelf bottom boundary layer due to the action of surface wind waves. The study area is situated off-shore and north-west of Elba Island in the Western Mediterranean Sea, an area known to be characterized by rhodolith beds. A binomial logistic regression model is used in order to analyse the relationship between wind-wave energy at sea bottom, bathymetry and rhodolith bed occurrence. The results indicate a positive correlation between rhodolith bed occurrence and wave energy, while the relation with bathymetry is weaker in all the trials. The wave energy confidence interval associated to the rhodolith bed probability is also estimated, thereby informing on wind wave energy values required for the modelling of this particular benthic habitat in off-shore shelf areas.

Rhodolith Beds Heterogeneity along the Apulian Continental Shelf (Mediterranean Sea)

“…The clear separation of Armeleia shoal from the other two areas (Figure 6) suggested that a combination of environmental drivers (e.g., currents and sedimentation) possibly shaped a different rhodolith assemblage in this area in terms of species composition, rhodolith growth forms and cover. Besides temperature, wind waves, nutrients and irradiance levels as a function of photosynthesis, calcification and respiration process [86][87][88], bottom currents represent important variables governing rhodolith occurrence and development. In fact, different hydrodynamic regimes can influence RB composition and rhodolith morphotype [33,89].…”

Addressing ocean planning challenges in a highly crowded sea space: a case study for the regional sea of Catalonia (Western Mediterranean)

“…It is the framework mentioned in the Royal Decree 150/2023 approving the Spanish Maritime Spatial Plan in February 2023. To monitor the 30% protection target in the study area we apply the method developed by the European Environment Information and Observation Network (EIONET; Agnesi et al , 2020 ). EIONET performs three-annual monitoring of progress in MPA implementation in European seas and is therefore guiding instrument for the monitoring of the 30% protection target.…”

Cryptofaunal diversity in fringing reef rhodoliths

“…Similarly, sufficient energy may be needed to clear rhodoliths of sediment, while greater movement may transport rhodoliths into environments where they are subject to burial (Jeong et al 2020). As such, wave energy optima may reconcile the alternating attribution of rhodolith presence to both higher (e.g., Marrack 1999;Agnesi et al 2020) and lower wave energy settings (e.g., Bosence 1976;Piller and Rasser 1996).…”

“…However, only a limited number of images of sufficient quality were available to us. Larger waves pertinent to open ocean wave climate are easier to reconstruct (e.g., SAR: Jackson and Apel 2004); thus, studies at larger scales in deeper water settings (Italy: Agnesi et al 2020;Ireland: Joshi and Farrell 2020) provide more quantitative reconstructions of rhodolith environment.…”