title: Observational information on a temperate reef community helps understanding the marine climate and ecosystem shift of the 1980-90s.
abstract: The dearth of long-time series hampers the measurement of the ecosystem change that followed the global marine climate shift of the 1980-90s. The sessile communities of Portofino Promontory reefs (Ligurian Sea, NW Mediterranean) have been discontinuously studied since the 1950s. Collating information from various sources, three periods of investigations have been distinguished: 1) 1950-70s; 2) 1980-90s; 3) 2000-10s. A cooler phase in time 1 was followed by a rapid warming in time 2, to stabilize at about 0.5°C higher in time 3. Human pressure grew impressively, especially after the establishment of a MPA in 1999. Multivariate analyses evidenced a major change of community composition in time 2. Some species disappeared or got rarer, many found refuge at depth, and among the newcomers there were recently introduced alien species. This study demonstrated the importance of descriptive historical data to understand magnitude and pattern of change in the long term evolution of marine ecosystems.
authors.affiliation: Aix Marseille University, , Avignon University, CNRS, IRD, IMBE, Station Marine d'Endoume, Chemin de la Batterie des Lions, 13007 Marseille, France. Electronic address: gatti.giulia25@gmail.com.
authors.forename: Giulia
authors.initials: G
authors.lastname: Gatti
authors.affiliation: DiSTAV (Department of Earth, Environment and Life Sciences), University of Genoa, Corso Europa 26, 16132 Genoa, Italy.
authors.forename: Carlo Nike
authors.initials: CN
authors.lastname: Bianchi
authors.affiliation: DiSTAV (Department of Earth, Environment and Life Sciences), University of Genoa, Corso Europa 26, 16132 Genoa, Italy.
authors.forename: Monica
authors.initials: M
authors.lastname: Montefalcone
authors.affiliation: Marine Protected Area of Portofino, Viale Rainusso 1, 16038 Santa Margherita Ligure, Italy.
authors.forename: Sara
authors.initials: S
authors.lastname: Venturini
authors.affiliation: Regione Liguria, Settore Sviluppo Sostenibile, Parchi e Biodiversità, Via D'Annunzio 111, 16121 Genoa, Italy.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Diviacco
authors.affiliation: DiSTAV (Department of Earth, Environment and Life Sciences), University of Genoa, Corso Europa 26, 16132 Genoa, Italy.
authors.forename: Carla
authors.initials: C
authors.lastname: Morri
mesh_terms: D000818:Animals; D044822:Biodiversity; D057231:Climate Change; D057894:Coral Reefs; D017753:Ecosystem; D004777:Environment; D004784:Environmental Monitoring / Q000379:methods; D006801:Humans; D008522:Mediterranean Sea; D015999:Multivariate Analysis; D011157:Population Dynamics
keywords: Baselines; Ecosystem shifts; Historical data; Mediterranean Sea; Rocky reefs; Sessile macrobenthos