Use of Hydroacoustic Methods for the Identification of Potential Seabed Habitats for Small Pelagic Fish Schools in the Strait of Sicily

Study of benthic foraminifera in the Continental Shelf of the Gulf of Gela (Sicilian Channel) and their possible use as bioindicators

Genetic and morphometric variation of Mediterranean hake, Merluccius merluccius, in the Strait of Sicily (Central Mediterranean)

Allozyme, morphometric and growth analyses were applied to samples collected in the Strait of Sicily (central Mediterranean Sea) to test the hypothesis of the existence of a unique hake stock (Merluccius merluccius) in the study area. The level of genetic variation was detected from five polymorphic loci (ADH*, PGI-1*, PGI-2*, PGM*, SOD-1*). The average observed heterozygosity amounted to 0.421, while the average expected was 0.353. Weir & Cockerham statistics showed no heterogeneity, except for the single PGI? locus (theta = 0.011; P 0.05). Morphometric analyses revealed some differentiation. Females showed different relationships in six out of eight morphometric indices with total length,…

Primary productivity variability on the Atlantic Iberian Margin over the last 70,000 years: evidence from coccolithophores and fossil organic compounds

This study analyzes coccolithophore abundance fluctuations (e.g., Emiliania huxleyi, Gephyrocapsa specimens, and Florisphaera profunda) in core MD01-2444 sediment strata retrieved at the Iberian Margin, northeastern Atlantic Ocean. Coccolithophores are calcareous nannofossils, a major component of the oceanic phytoplankton, which provide information about past ecological and climatological variability. Results are supported by data on fossil organic compounds (sea surface temperatures, alkenones, and n-hexacosan-1-ol index) and geochemical analyses (benthic δ13Ccc and planktonic δ18Occ isotopes). Three scenarios are taken into account for this location at centennial-scale resolution over th…

Calcareous Nannofossil Assemblages from the Central Mediterranean over the last Four Centuries.

Studio delle tanatocenosi a foraminiferi bentonici nel Golfo di Gela

THE EFFECT OF HEAVY METALS ON BENTHIC FORAMINIFERA IN THE GULF OF GELA (SICILIAN CHANNEL)

Benthic foraminifera are very sensitive to oceanographic parameter variations, to which they rapidly response through changes in the abundance and/or richness of their associations and in morphological variations of their shell. Many studies have used benthic foraminifera as bioindicators. We investigated recent benthic foraminiferal assemblages in the Gulf of Gela (Sicilian Channel, Mediterranean Sea), examining their relative abundance, specific richness and morphological abnormalities, to highlight a possible correlation with oceanographic features and the concentration of heavy metals in sediments. Sediment was sampled in summer 2006 using box corers in four stations at increasing dista…

Holocene millennial-scale productivity variations in the Sicily Channel (Mediterranean Sea)

This study analyzes coccolithophore abundance fluctuations (e.g., Emiliania huxleyi, Gephyrocapsa specimens, and Florisphaera profunda) in core MD01-2444 sediment strata retrieved at the Iberian Margin, northeastern Atlantic Ocean. Coccolithophores are calcareous nannofossils, a major component of the oceanic phytoplankton, which provide information about past ecological and climatological variability. Results are supported by data on fossil organic compounds (sea surface temperatures, alkenones, and n-hexacosan-1-ol index) and geochemical analyses (benthic ?13Ccc and planktonic ?18Occ isotopes). Three scenarios are taken into account for this location at centennial-scale resolution over th…

Lo stato dell’ambiente marino nell’area del Canale di Sicilia in prossimità del SIN di Gela.

Viene illustrata in questa nota l’attuale condizione in cui si trova lo stato dell’ambiente marino nell’area del Canale di Sicilia immediatamente a ridosso della costa merdionale delle Sicilia dal Golfo di Gela alla costa iblea. Lo stato dell’ambiente in oggetto viene valutato in base alla distribuzione di alcuni metalli in tracce normalmente ritenuti fra i più significativi per gli scopi prefissati, esaminati lungo la colonna d’acqua e nei sedimenti superficiali di fondale. I risultati ottenuti, illustrati anche attraverso un’indagine statistica multivariata, indicano un arricchimento superficiale della colonna d’acqua in lantanio che può essere ascritto tanto ad un’origine litogenica, qua…

Linking air–sea energy fluxes and European anchovy potential spawning ground.

The physical and chemical processes of the sea greatly affect the reproductive biology of fishes, mainly influencing both the numbers of spawned eggs and the survivorship of early stages up to the recruitment period. In the central Mediterranean, the European anchovy constitutes one of the most important fishery resource. Because of its short living nature and of its recruitment variability, associated to high environmental variability, this small pelagic species undergo high interannual fluctuation in the biomass levels. Despite several efforts were addressed to characterize fishes spawning habitat from the oceanographic point of view, very few studies analyze the air-sea exchanges effects…