title: Towards a predictive model to assess the natural position of the Posidonia oceanica seagrass meadows upper limit.
abstract: The upper portion of the meadows of the protected Mediterranean seagrass Posidonia oceanica occurs in the region of the seafloor mostly affected by surf-related effects. Evaluation of its status is part of monitoring programs, but proper conclusions are difficult to draw due to the lack of definite reference conditions. Comparing the position of the meadow upper limit with the beach morphodynamics (i.e. the distinctive type of beach produced by topography and wave climate) provided evidence that the natural landwards extension of meadows can be predicted. An innovative model was therefore developed in order to locate the region of the seafloor where the meadow upper limit should lie in natural conditions (i.e. those governed only by hydrodynamics, in absence of significant anthropogenic impact). This predictive model was validated in additional sites, which showed perfect agreement between predictions and observations. This makes the model a valuable tool for coastal management.
authors.affiliation: Aix-Marseille Université, CEREGE CNRS-IRD UMR 34, Aix en Provence, France; SEAMap Ltd., Environmental Consulting, Borghetto Santo Spirito, Italy. Electronic address: vacchi@cerege.fr.
authors.forename: Matteo
authors.initials: M
authors.lastname: Vacchi
authors.affiliation: Department of Earth, Environmental and Life Sciences, University of Genoa, Italy.
authors.forename: Monica
authors.initials: M
authors.lastname: Montefalcone
authors.affiliation: Department of Earth, Environmental and Life Sciences, University of Genoa, Italy; SEAMap Ltd., Environmental Consulting, Borghetto Santo Spirito, Italy.
authors.forename: Chiara F
authors.initials: CF
authors.lastname: Schiaffino
authors.affiliation: UR 227 - "CoReUs2" IRD - Institut de Recherche pour le Développement, Laboratoire Arago, Banyuls-sur-Mer, France; SEAMap Ltd., Environmental Consulting, Borghetto Santo Spirito, Italy.
authors.forename: Valeriano
authors.initials: V
authors.lastname: Parravicini
authors.affiliation: Department of Earth, Environmental and Life Sciences, University of Genoa, Italy.
authors.forename: Carlo Nike
authors.initials: CN
authors.lastname: Bianchi
authors.affiliation: Department of Earth, Environmental and Life Sciences, University of Genoa, Italy.
authors.forename: Carla
authors.initials: C
authors.lastname: Morri
authors.affiliation: Department of Earth, Environmental and Life Sciences, University of Genoa, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Ferrari
mesh_terms: D035961:Alismatales / Q000502:physiology*; D002980:Climate; D004777:Environment; D008962:Models, Theoretical; D009792:Oceans and Seas
keywords: Ecological modelling; Mediterranean Sea; Nearshore hydrodynamics; Posidonia oceanica; Reference conditions; Seagrass