title: Impact of a harbour construction on the benthic community of two shallow marine caves.
abstract: Marine caves are unique and vulnerable habitats, threatened by multiple global and local disturbances. Whilst the effects of climate change on marine caves have already been investigated, no information exists about the effects of local human impacts, such as coastal development, on these habitats. This study investigated the impact of the construction of a touristic harbour on two shallow underwater marine caves in the Ligurian Sea (NW Mediterranean). As a standard methodology for monitoring marine caves does not exist yet, changes over time on the benthic community were assessed adopting two different non-taxonomic descriptors: trophic guilds and growth forms. Harbour construction caused an increase of sediment load within the caves, with a consequent decline of filter feeder organisms. Abundance of small organisms, such as encrusting and flattened sponges, was greatly reduced in comparison to organisms with larger and erect growth forms, such as domed mounds and pedunculated sponges. Our study indicated that growth forms and trophic guilds are effective descriptors for evaluating changes over time in marine caves, and could be easily standardised and applied in monitoring plans. In addition, as the harbour construction impacted differently according to the cave topography, the use of a systematic sampling in different zones of an underwater cave is recommended.
authors.affiliation: DiSTAV, Department of Earth, Environment and Life Sciences, University of Genoa, Corso Europa 26, 16132 Genoa, Italy.
authors.forename: Ettore
authors.initials: E
authors.lastname: Nepote
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: Carla
authors.initials: C
authors.lastname: Morri
authors.affiliation: DiSTAV, Department of Earth, Environment and Life Sciences, University of Genoa, Corso Europa 26, 16132 Genoa, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Ferrari
authors.affiliation: DiSTAV, Department of Earth, Environment and Life Sciences, University of Genoa, Corso Europa 26, 16132 Genoa, Italy. Electronic address: montefalcone@dipteris.unige.it.
authors.forename: Monica
authors.initials: M
authors.lastname: Montefalcone
mesh_terms: D000818:Animals; D059001:Aquatic Organisms / Q000502:physiology*; D059552:Caves; D057231:Climate Change; D060389:Construction Industry; D017753:Ecosystem; D004784:Environmental Monitoring; D011161:Porifera; D018570:Risk Assessment; D014876:Water Pollution / Q000032:analysis / Q000706:statistics & numerical data
keywords: Growth forms; Local disturbance; Marine caves; Mediterranean Sea; Non-taxonomic descriptors; Sediment load; Trophic guilds