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The polychaete assemblages from an escarpment area in the western Ionian Sea are characterised in terms of species richness, evenness and trophic composition. Moreover, the first occurrence of the genus Barantolla in the Mediterranean Sea, and of Lumbrinerides carpinei and Exogone (Parexogone) campoyi in Italian waters, is reported. Aricidea trilobata Laubier and Ramos, 1974 is redescribed on the basis of new material with the new name Aricidea (Acmira) jeaneteae, together with a brief description of two deep-water species belonging to the genus Levinsenia. [ABSTRACT FROM AUTHOR]

The Ligurian Sea is a deep basin in the northernmost sector of the western Mediterranean which shows peculiar hydrodynamic and meteo-oceanographic features. The coasts of the Ligurian Sea are among the most urbanised and industrialised along the Italian coastline: the main causes of disturbance being littoral urban development and harbour activities, the building of littoral rail- and highways, and the presence of several polluted discharges. This review, by evaluating the huge scientific output published in the last three decades, describes and discusses the most important geological, hydrological and biological characteristics of the Ligurian Sea. We show that this regional sea has largely been investigated in terms of its geological and structural evolution, as well as in terms of the sedimentation dynamics of the littoral and deep bottoms, with particular attention to the sedimentation balance of the beaches and their erosive processes. We report that the prevalent hydrodynamic and meteo-oceanographic conditions favour a continuous exchange of coastal water masses, and that the seasonal and interannual dynamics of water masses can effects the local climate, with direct and indirect consequences on fish and benthic communities documented in the last decade. We stress that although recent studies offer good knowledge of the distribution of coastal benthic communities, only scant information is available for the whole continental shelf, the submarine canyons and the rocky bathyal bottoms. Our meta-analysis reveals that significant fishing activities are monitored, but also that certain sectors of the biological resource are suffering, and suggests the set up of appropriate management measures. The Ligurian Sea hosts a number of Marine Protected Areas (MPAs) of high relevance, while the institution of the Whale Sanctuary completes the protection policy of the Regione Liguria. Our meta-analysis points out the need for long-term studies, based primarily on the analysis of those areas of the Ligurian Sea that have been little investigated to date. Finally, only properly addressed studies, using experimental approaches and along appropriate spatial and temporal scales, might allow us to understand the functioning of the Ligurian marine ecosystems, evaluate their health conditions and the dynamics of the main variables that affect the distribution of the single species (including species of high economic value) and benthic communities. [ABSTRACT FROM AUTHOR]

An external genetic input of Posidonia oceanica fruits dispersed by currents in the Ligurian Sea (Western Mediterranean) was investigated. During 2003-2004, when a massive fruiting event occurred, fruits were collected from plants at Monterosso al Mare (meadow) and compared with stranded fruits sampled in front of the meadow and downcurrent in Tuscany along 80 km of the coast. After their growth in culture, the plants were analysed using 10 random amplified polymorphic DNA (RAPD) molecular markers. Cluster analysis of similarity showed four distinct genetic populations. One group included parental plants from Monterosso and stranded fruits with the same genetic traits. The second group was formed by fruits stranded in the southern sector (Tuscany), and the third and the fourth groups were samples taken onshore, in front of the meadow, which appeared very different from the other two groups. Results evidenced the probability of the arrival of a new genetic population of nearly 40%, and it seems likely that the stranded fruits of external provenance did not come from the nearest P. oceanica meadows of Tuscany but were probably carried ashore by the Corsica current, as supported by an oceanographic analysis. [ABSTRACT FROM AUTHOR]

The processes occurring in the marine environment at the interface between sea and glaciers in Arctic fiords are often poorly investigated, mainly due to logistical reasons. Two multidisciplinary campaigns have been carried out in September 2000 and 2001 in the inner part of Kongsfiord to collect late-summer data on oceanographic processes at the peculiar environment close to glaciers front. Warmer oceanic waters enter the inner Kongsfiord across the southern passage of the moraine 20–25 m deep. Surface waters get colder and fresher flowing northward along the glaciers' front and exit across the recently opened passage of Blømstrand. The water column is well stratified with cold lenses of freshwater outflowing from the glaciers at the surface. Sedimentation sharply decreases with distance from the glaciers' front. The inter-moraine depression is the area where preferential sediment accumulation occurs (up to 1.8 g cm-2 yr-1), with a residence time of particles in the water column at around 5 days. [ABSTRACT FROM AUTHOR]

A quantitative study of sessile macroepibenthos was carried out in Palaeochori Bay (Milos Island, Aegean Sea) using underwater, framed, still photographs. Images of sessile epibenthos were collected from four different rocky shoals at 10–35 m depth: shoal CR, where continuous vent activity was evident, and shoals E, ST and S, without evident vent activity. At each site images were taken from four stations with different slopes. Three replicate photo-samples were collected at each station. Correspondence analysis showed that the distribution of epibenthic communities was mainly related to `normal' environmental gradients such as slope, distance from the shore and depth. No clear, univocal effect of venting was recognized. However, small differences between the vent and non-vent sites were detected under overhangs, where vent effects could be locally amplified due to the entrapment of venting fluids. [ABSTRACT FROM AUTHOR]