Research Interests: Geography, Geomorphology, Chemistry, Hydrology, Environmental policy, and 15 moreMarine Protected Areas, Biodiversity, Mediterranean Sea, Environmental Sciences, Meta Analysis, Continental shelf, Introduced species, CHEMICAL SCIENCES, Marine Protected Area, Coastal waters, Economic Value, Marine ecosystem, Long Term Study, Benthic Communities, and Canyon
Research Interests:
Research Interests: Chemical Engineering, Environmental Science, Oceanography, Nanoindentation, Environmental Chemistry, and 13 moreInternational Marine Environmental Law, Medicine, Biological Sciences, SEM, Antarctica, Environmental Sciences, Ocean acidification, Ph, Pollution, CHEMICAL SCIENCES, Shell, Benthos, and Aquatic science
Research Interests:
Research Interests:
... Doyotte, A., Cossu, C., Jacquin, MC, Babut, M., and Vasseur (1997). Antioxidant enzymes, glutathione and lipid peroxidation as relevant biomarkers of experimental or field exposure in the gills and the digestive gland of the... more
... Doyotte, A., Cossu, C., Jacquin, MC, Babut, M., and Vasseur (1997). Antioxidant enzymes, glutathione and lipid peroxidation as relevant biomarkers of experimental or field exposure in the gills and the digestive gland of the freshwater bivalve Unio tumidus. ... Forshaw, PJ (1977). ...
Research Interests:
Research Interests:
Research Interests:
The Northwestern Mediterranean Sea is a microtidal system, where barometric pressure and local wave exposure play the paramount role in sea water level variation. Herein, Cystoseira amentacea var. stricta and Cystoseira compressa are... more
The Northwestern Mediterranean Sea is a microtidal system, where barometric pressure and local wave exposure play the paramount role in sea water level variation. Herein, Cystoseira amentacea var. stricta and Cystoseira compressa are common species, generally co-occurring on exposed shores where they form a fucoid belt that characterise a narrow area called the infralittoral fringe. To better understand the eventual zonation patterns and the interspecific relationships of Cystoseira species, a multi-response manipulative experiment based on cross-transplantation, was set up. The fitness of the two species was assessed in terms of survival, growth and reproductive conditions; the role of a given Cystoseira and of the presence of a hard to measure environmental gradient was assessed on the recruitment of the two species and on the composition of assemblages re-colonising the bare substrate. Our results highlight a different response to the manipulation of the two species: while C. com...
Research Interests:
Inflammation and oxidative stress are part of the complex biological responses of body tissues to harmful stimuli. In recent years, due to the increased understanding that oxidative stress is implicated in several diseases, pharmaceutical... more
Inflammation and oxidative stress are part of the complex biological responses of body tissues to harmful stimuli. In recent years, due to the increased understanding that oxidative stress is implicated in several diseases, pharmaceutical industries have invested in the research and development of new antioxidant compounds, especially from marine environment sources. Marine seaweeds have shown the presence of many bioactive secondary metabolites, with great potentialities from both the nutraceutical and the biomedical point of view. In this study, 50%-ethanolic and DMSO extracts from the species C. amentacea var. stricta were obtained for the first time from seaweeds collected in the Ligurian Sea (north-western Mediterranean). The bioactive properties of these extracts were then investigated, in terms of quantification of specific antioxidant activities by relevant ROS scavenging spectrophotometric tests, and of anti-inflammatory properties in LPS-stimulated macrophages by evaluatio...
Research Interests:
The pan-Mediterranean project M3-HABs regarding monitoring of harmful algal blooms, with particular reference to the benthic dinoflagellate Ostreopsis, started in 2014 in the framework of the ENPI-CBCMED Programme. The specific objective... more
The pan-Mediterranean project M3-HABs regarding monitoring of harmful algal blooms, with particular reference to the benthic dinoflagellate Ostreopsis, started in 2014 in the framework of the ENPI-CBCMED Programme. The specific objective of the project was to provide a common strategy for monitoring benthic toxic microalgae, through the development of new, more efficient and common procedures and protocols, making the process mostly cost and time effective, allowing for most efficient monitoring designs, increasing the knowledge on environmental drivers affecting Ostreopsis blooms and translate this into a forecasting tool, and improving the general awareness of the risks related to Ostreopsis. The following results were obtained: a larger awareness of the risks associated with the Ostreopsis blooms, an appropriate diffusion of cautionary measures set up, the production of common monitoring protocols, the development of new technologies for species-specific identification and counti...
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
In the Mediterranean Sea, brown algae belonging to the Cystoseira genus play a valuable role as foundation species. Due to evidences of regression/loss of the habitats of these species caused by the interplay of human and climatic... more
In the Mediterranean Sea, brown algae belonging to the Cystoseira genus play a valuable role as foundation species. Due to evidences of regression/loss of the habitats of these species caused by the interplay of human and climatic disturbances, active restoration measures have been encouraged by EU regulations. In particular, nondestructive restoration techniques, which avoid the depletion of threatened species in donor populations, are strongly recommended. In the framework of the EU project ROCPOP-Life, the first ex situ outplanting experience of Cystoseira amentacea var. stricta has been implemented in the Cinque Terre Marine Protected Area (northwestern Mediterranean). A total of 400 clay tiles, hosting approximately three mm-long germlings of C. amentacea, were fixed to the rocky shore with screws: the tiles were monitored for the next 2 months by photographic sampling, and survival (presence/absence of juveniles on the tiles), cover and growth were assessed. Additional samplin...
Research Interests:
Abstract This study evaluated the growth of the purple sea urchin Paracentrotus lividus, fed with two diets, in sea- and land-based systems compared to wild populations. The experiments investigated the effects of the feeding regimes on... more
Abstract This study evaluated the growth of the purple sea urchin Paracentrotus lividus, fed with two diets, in sea- and land-based systems compared to wild populations. The experiments investigated the effects of the feeding regimes on gonad yield, nutritional traits and overall quality. Sea-based trials were performed by the CNR of Taranto (Trial S), whereas land-based trials were performed in the facilities of the University of Cagliari (Trial L). Urchins fed with a laboratory prepared pelletized diet (P), and a mix diet PU (50% of P-Diet and 50% of fresh Ulva sp.) were compared to wild urchins (W). In both trials the experimental diets supported a gonad growth when compared to wild population (p
Research Interests:
Research Interests:
Research Interests:
Due to multiple impacts, Cystoseira forests are experiencing a significant decline, which is affecting the ecosystem services they provide. Despite conservation efforts, there is an urgent need to develop best practices and large-scale... more
Due to multiple impacts, Cystoseira forests are experiencing a significant decline, which is affecting the ecosystem services they provide. Despite conservation efforts, there is an urgent need to develop best practices and large-scale restoration strategies. To implement restoration actions, we developed an ex situ protocol for the cultivation of Cystoseira. amentacea var. stricta, aimed at reducing the time needed for laboratory culture, thus avoiding prolonged maintenance and minimizing costs. Specifically, we tested the effects of temperature, light and substratum on settlement and growth of early life stages using a factorial experiment. Temperature (20 and 24°C) and photoperiod (15L:9D) were selected to reflect the conditions experienced in the field during the reproductive period. Two light intensities (125 and 250 μmol photons m-2s-1) were selected to mimic the condition experienced in the absence of canopy (i.e. barren-higher light intensity) or in the understory (lower lig...
Research Interests:
Research Interests:
Connectivity between populations influences both their dynamics and the genetic structuring of species. In this study, we explored connectivity patterns of a marine species with long-distance dispersal, the edible common sea urchin... more
Connectivity between populations influences both their dynamics and the genetic structuring of species. In this study, we explored connectivity patterns of a marine species with long-distance dispersal, the edible common sea urchin Paracentrotus lividus, focusing mainly on the Adriatic-Ionian basins (Central Mediterranean). We applied a multidisciplinary approach integrating population genomics, based on 1,122 single nucleotide polymorphisms (SNPs) obtained from 2b-RAD in 275 samples, with Lagrangian simulations performed with a biophysical model of larval dispersal. We detected genetic homogeneity among eight population samples collected in the focal Adriatic-Ionian area, whereas weak but significant differentiation was found with respect to two samples from the Western Mediterranean (France and Tunisia). This result was not affected by the few putative outlier loci identified in our dataset. Lagrangian simulations found a significant potential for larval exchange among the eight A...
Research Interests:
Harmful algal blooms have been increasing in frequency in recent years, and attention has shifted from describing to modeling and trying to predict these phenomena, since in many cases they pose a risk to human health and coastal... more
Harmful algal blooms have been increasing in frequency in recent years, and attention has shifted from describing to modeling and trying to predict these phenomena, since in many cases they pose a risk to human health and coastal activities. Predicting ecological phenomena is often time and resource consuming, since a large number of field collected data are required. We propose a novel approach that involves the use of modeled meteorological data as input features to predict the concentration of the toxic benthic dinoflagellate Ostreopsis cf. ovata in seawater. Ten meteorological features were used to train a Quantile Random Forests model, which was then validated using field collected concentration data over the course of a summer sampling season. The proposed model was able to accurately describe Ostreopsis abundance in the water column in response to meteorological variables. Furthermore, the predictive power of this model appears good, as indicated by the validation results, especially when the quantile for predictions is tuned to match management requirements. The Quantile Random Forests method was selected, as it allows for greater flexibility in the generated predictions, thus making this model suitable as a tool for coastal management. The application of this approach is novel, as no other models or tools that are adaptable to this degree are currently available. The model presented here was developed for a single species over a limited geographical extension, but its methodological basis appears flexible enough to be applied to the prediction of HABs in general and it could also be extended to the case of other ecological phenomena that are strongly dependent on meteorological drivers, that can be independently modeled and potentially globally available.
Research Interests:
Abstract Coral reefs are threatened by multiple global and local disturbances. The Maldives, already heavily hit by the 1998 mass bleaching event, are currently affected also by growing tourism and coastal development that may add to... more
Abstract Coral reefs are threatened by multiple global and local disturbances. The Maldives, already heavily hit by the 1998 mass bleaching event, are currently affected also by growing tourism and coastal development that may add to global impacts. Most of the studies investigating effects of local disturbances on coral reefs assessed the response of communities along a horizontal distance from the impact source. This study investigated the status of a Maldivian coral reef around an island where an international touristic airport has been recently (2009–2011) built, at different depths along the reef profile (5–20 m depth) and considering the change in the percentage of cover of five different non-taxonomic descriptors assessed through underwater visual surveys: hard corals, soft corals, other invertebrates, macroalgae and abiotic attributes. Eight reefs in areas not affected by any coastal development were used as controls and showed a reduction of hard coral cover and an increase of abiotic attributes (i.e. sand, rock, coral rubble) at the impacted reef. However, hard coral cover, the most widely used descriptor of coral reef health, was not sufficient on its own to detect subtle indirect effects that occurred down the reef profile. Selecting an array of descriptors and considering different depths, where corals may find a refuge from climate impacts, could guide the efforts of minimising local human pressures on coral reefs.
Research Interests:
The new benthic toxic dinoflagellate Ostreopsis fattorussoi sp. nov. is described from eastern Mediterranean Sea Lebanon and Cyprus coasts, supported by morphological and molecular data. The plate formula, Po, 3',... more
The new benthic toxic dinoflagellate Ostreopsis fattorussoi sp. nov. is described from eastern Mediterranean Sea Lebanon and Cyprus coasts, supported by morphological and molecular data. The plate formula, Po, 3', 7'', 6c, 7s, 5''', 2'''', is typical for the Ostreopsis genus. It differs from all other Ostreopsis species in that i) the curved suture between plates 1' and 3' makes them approximately hexagonal, ii) the 1' plate lies in the left-half of the epitheca and is obliquely orientated leading to a characteristic shape of plate 6''. The round thecal pores are bigger than the other two Mediterranean species (O. cf. ovata and O. cf. siamensis). O. fattorussoi is among the smallest species of the genus (DV: 60.07±5.63 μm, AP: 25.66±2.97 μm, W: 39.81±5.05 μm) along with O. ovata. Phylogenetic analyses based on the LSU and ITS rDNA shows that O. fattorussoi belongs to the Atlantic/Mediterranean Ostreopsis spp. clade separated from the other Ostreopsis species. O. fattorussoi produces OVTX-a and structural isomers OVTX-d and -e, O. cf. ovata is the only other species of this genus known to produce these toxins. The Lebanese O. fattorussoi did not produce the new palytoxin-like compounds (ovatoxin-i, ovatoxin-j1 , ovatoxin-j2 , and ovatoxin-k) that were previously found in O. fattorussoi from Cyprus. The toxin content was in the range of 0.28-0.94 pg. cell(-1) . In Lebanon coast, O. fattorussoi was recorded throughout the year 2015 (temperature range 18-31.5 °C), with peaks in June and August. This article is protected by copyright. All rights reserved.
Research Interests:
Research Interests:
The frequency and geographic extension of microalgae and gelatinous zooplankton blooms seem to have been increasing worldwide over recent decades. In particular, the harmful dinoflagellate Ostreopsis cf. ovata and the Schyphozoan... more
The frequency and geographic extension of microalgae and gelatinous zooplankton blooms seem to have been increasing worldwide over recent decades. In particular, the harmful dinoflagellate Ostreopsis cf. ovata and the Schyphozoan jellyfish Aurelia sp. are two of the most frequent and long lasting species forming blooms in the Mediterranean Sea. A kind of interaction among any of their life cycle stages (i.e. planula-polyp-ephyrae vs Ostreopsis cells) can likely occur, although in this area there are no data available on the co-occurrence of these species. The aim of this study was to investigate, for the first time, the potential noxious effect of O. cf. ovata on different life stages of Aurelia sp. (polyps and ephyrae), testing several concentrations of whole algal culture. Rsults of toxicity bioassay highlighted that ephyrae, but not polyps, are affected by this harmful dinoflagellate and comparisons among other model organisms show that Aurelia sp. ephyrae are the most sensitive model organism tested so far (EC=10.5cells/mL). These findings suggest an interesting scenario on the interaction of these two bloom forming species in the natural marine environment.
Research Interests:
Blooms of benthic dinoflagellates of the genus Ostreopsis (mainly O. cf. ovata and occasionally O. cf. siamensis) represent a serious concern for humans in the Mediterranean area, due to production of palytoxin-like compounds listed among... more
Blooms of benthic dinoflagellates of the genus Ostreopsis (mainly O. cf. ovata and occasionally O. cf. siamensis) represent a serious concern for humans in the Mediterranean area, due to production of palytoxin-like compounds listed among the most potent marine toxins known. In this work, six strains of Ostreopsis sp. from Cyprus Island were analyzed through an integrated approach based on molecular, chemical, and eco-toxicological methods. Cypriot Ostreopsis sp. was found to be a species distinct from O. cf. ovata and O. cf. siamensis, belonging to the Atlantic/Mediterranean Ostreopsis spp. clade. Some variability in toxin profiles emerged: three strains produced ovatoxin-a (OVTX-a), OVTX-d, OVTX-e, and isobaric palytoxin, so far found only in O. cf. ovata; the other three strains produced only new palytoxin-like compounds, which we named ovatoxin-i, ovatoxin-j1, ovatoxin-j2, and ovatoxin-k. The new ovatoxins present the same carbon skeleton as ovatoxin-a, differing primarily in an...
Research Interests:
ABSTRACT Mariculture is a relatively new activity that is expanding globally and interacts with other coastal uses. Therefore, it is necessary to allocate suitable sites from environmental, economic and social points of view, involving... more
ABSTRACT Mariculture is a relatively new activity that is expanding globally and interacts with other coastal uses. Therefore, it is necessary to allocate suitable sites from environmental, economic and social points of view, involving different stakeholders in the decision-making process. In particular, in the Ligurian Sea (Italy), for its environmental characteristics and tradition, fish farming should be further boosted and an accurate marine spatial planning should be done. This paper presents a spatial multi-criteria evaluation (SMCE) addressed to identify suitable areas for siting offshore medium size fish farms in the Ligurian Sea at the regional scale. The SMCE procedure follows an integrated approach that can be potentially adapted and applied to any coastal system. The site selection is based on the definition of criteria that assess their suitability and on conditions related to the entire study area. Suitability values are ranked on a scale from 1 (suitable) to 10 (optimal). More than 9000 ha were identified and almost 40% of this area gets high suitability values, from 7 to 9, pointing out the untapped potential for Ligurian marine coastal zone. Results demonstrate that our SMCE, and in particular its procedure, allows identifying the most suitable areas in an easy and quick way and solving effectively the complex spatial problem of suitable site selection for fish farming.
Research Interests:
Spatial distributions of bacterial and protozoan abundance and biomass were investigated in the sediments of Terra Nova Bay (Ross Sea) at depths ranging from 36 to 223m, during January-February 1994. Microbial parameters were compared to... more
Spatial distributions of bacterial and protozoan abundance and biomass were investigated in the sediments of Terra Nova Bay (Ross Sea) at depths ranging from 36 to 223m, during January-February 1994. Microbial parameters were compared to the distribution of several food indicators (such as phytopigments, lipids, proteins, total and soluble carbohydrates) in order to provide quantitative information about the different components of the benthic microbial loop and identify which factors are responsible for microbial distribution. As suggested by the high content of chloroplastic pigment equivalents (on average 29.0 µg g-1 dry wt), proteins (1.9 mg g-1 dry wt) and carbohydrates (5.3 mg g-1 dry wt), the sediments of Terra Nova Bay were characterized by large amounts of deposited primary organic material. These values are among the highest reported for coastal sediments. Sediment organic matter was mostly composed of labile compounds and 98% of the total carbohydrate content was composed of soluble carbohydrates. Benthic bacterial densities were 1 to 2 orders of magnitude lower than those previously reported in Antarctic sediments or at temperate latitudes (on average 1.7 × 107 cells g-1 dry wt). By contrast, microprotozoa showed high densities (on average 873 × 103 cells g-1) and accounted for 11% of the total microbial biomass. Such high protozoan densities are comparable to those reported for highly productive systems. Bacteria and protozoa were significantly correlated with phytopigment and protein concentrations indicating a response to the organic matter accumulation. Protozoan density was significantly correlated to bacterial number and biomass. Microbial communities in Terra Nova Bay sediments appeared to be mainly bottom-up controlled (i.e. dependent upon food source and substrate availability). However, the close relationship between protozoa and labile compounds and the high protozoan to bacterial biomass ratio stress the relevance of benthic protozoa that may represent, in coastal Antarctic sediments, the main vector for the direct transfer of detrital carbon and bacterial biomass to metazoan food web.
The Mediterranean Sea is a biodiversity hotspot containing between 15,000 and 20,000 marine species, nearly a quarter of which are endemic. The causes of the high Mediterranean biodiversity lie primarily in the turbulent geological... more
The Mediterranean Sea is a biodiversity hotspot containing between 15,000 and 20,000 marine species, nearly a quarter of which are endemic. The causes of the high Mediterranean biodiversity lie primarily in the turbulent geological history of the basin during the Tertiary and in the dramatic climatic fluctuations of the Quaternary. Both induced a rate of environmental change, and hence species occurrence, which acted as a 'biodiversity pump'. As a result, species with different biogeographic origins and affinities are found in the basin. A background of warm-temperate Atlantic-Mediterranean species, representing half of the biota, and the endemics are flanked by both boreal and subtropical species. Although the Mediterranean Sea as a whole constitutes a distinctive province of the Atlantic-Mediterranean biogeographic region, a great variety of climatic and hydrologic situations is found in its fairly isolated sub-basins. Thus, a dozen different biogeographic sectors can be r...
High Antarctic coastal marine environments are comparatively pristine with strong environmental gradients, which make them important places to investigate biodiversity relationships. Defining how different environmental features... more
High Antarctic coastal marine environments are comparatively pristine with strong environmental gradients, which make them important places to investigate biodiversity relationships. Defining how different environmental features contribute to shifts in beta-diversity is especially important as these shifts reflect both spatio-temporal variations in species richness and the degree of ecological separation between local and regional species pools. We used complementary techniques (species accumulation models, multivariate variance partitioning and generalized linear models) to assess how the roles of productivity, bio-physical habitat heterogeneity and connectivity change with spatial scales from metres to 100's of km. Our results demonstrated that the relative importance of specific processes influencing species accumulation and beta-diversity changed with increasing spatial scale, and that patterns were never driven by only one factor. Bio-physical habitat heterogeneity had a st...
Research Interests: Engineering, Geography, Physics, Chemistry, Biology, and 15 moreEcology, Biodiversity, Medicine, Multidisciplinary, Animals, Habitat Heterogeneity, Spatial Scale, Habitat loss, PLoS one, Environmental Gradient, Primary Production, Ecosystem, General Linear Model, Marine Protected Area, and Benthic Communities
Dynamics of Ostreopsis cf. ovata in the Mediterranean Sea, relations with environmental factors and consequences on shallow rocky ecosystems.
Mangialajo, L. ...et al.-- Oral presentation. 14th International Conference on Harmful Algae, 1-5 November 2010, Creta, Greece
Research Interests:
Recovery from disturbance is an important attribute of community dynamics. Temperate rocky shores will experience increases in both the type and intensity of impacts under future expected global change. To gauge the community response to... more
Recovery from disturbance is an important attribute of community dynamics. Temperate rocky shores will experience increases in both the type and intensity of impacts under future expected global change. To gauge the community response to these potential changes in the disturbance regime it is important to assess space occupancy and the temporal dynamics of key species over the recovery process. We experimentally disturbed replicated 1 m2 plots in the lower intertidal at 5 sites along the Ligurian rocky coast (North-western Mediterranean) and assessed early succession processes over 18 months. To identify colonisation processes and role of key species in affecting species richness on recovery trajectories, we monitored species composition at the cm-scale along fixed transects within the plots. Our results highlighted the role of a limited number of taxa in driving the recovery of species richness across sites, despite site variation in community composition. Settlement of new propagules and overgrowth were the principal pathway of space occupancy. We detected an important role for coralline algae, particularly the articulated Corallina elongata, in promoting the colonisation of a diverse range of colonists. The present study highlights the important role played by calcifying coralline macroalgae as substrate providers for later colonists, favouring recovery of biodiversity after disturbance. This pivotal role may be compromised in a future scenario of elevated cumulative disturbance, where ocean acidification will likely depress the role of coralline algae in recovery, leading to a general loss in biodiversity and community complexity.
Research Interests:
Ostreopsis sp. is a toxic marine benthic dinoflagellate that causes high biomass blooms, posing a threat to human health, marine biota and aquaculture activities, and negatively impacting coastal seawater quality. Species-specific... more
Ostreopsis sp. is a toxic marine benthic dinoflagellate that causes high biomass blooms, posing a threat to human health, marine biota and aquaculture activities, and negatively impacting coastal seawater quality. Species-specific identification and enumeration is fundamental because it can allow the implementation of all the necessary preventive measures to properly manage Ostreopsis spp. bloom events in recreational waters and aquaculture farms. The aim of this study was to apply a rapid and sensitive qPCR method to quantify Ostreopsis cf. ovata abundance in environmental samples collected from Mediterranean coastal sites and to develop site-specific environmental standard curves. Similar PCR efficiencies of plasmid and environmental standard curves allowed us to estimate the LSU rDNA copy number per cell. Moreover, we assessed the effectiveness of mitochondrial COI and cob genes as alternative molecular markers to ribosomal genes in qPCR assays for Ostreopsis spp. quantification.
Research Interests: Water quality, Biology, Environmental Monitoring, Medicine, Multidisciplinary, and 14 moreHumans, qPCR, RECREATION, Seawater, Plasmids, Gene Dosage, Marine Toxins, Harmful Algal bloom, Mediterranean region, Water Quality, Protozoan Proteins, Ribosomal DNA, real time polymerase chain reaction, and limit of detection
In Terra Nova Bay, the scallop Adamussium colbecki (Mollusca Bivalvia) constitutes large beds up to 70–80m in depth, reaching high values of density (50–60 ind m−2) and biomass (120 g m−2 DW soft tissues). Its population structure and... more
In Terra Nova Bay, the scallop Adamussium colbecki (Mollusca Bivalvia) constitutes large beds up to 70–80m in depth, reaching high values of density (50–60 ind m−2) and biomass (120 g m−2 DW soft tissues). Its population structure and biometrics have been studied during the summer of 1989/90, 1993/94, 1994/95 and 1995/96. The population of A. colbecki was studied in terms of abundance values and of size frequency distribution (modal length class: 70–75 mm). The growth rate of this species was assessed by X-ray methods and averaged 8 mm year−1. Biometrical measures were performed in order to assess the influence of the summer increase in food supply on the life cycle of the scallop, showing a strong coupling between food supply and gonad development. On the basis of the gonadosomatic index values (GSI) and of the occurrence of planktonic larvae some speculations are made on the reproductive behaviour of this scallop.
Research Interests:
The structure of a Mediterranean bathyal community living between 400 and 700 m depth in front of Portofino Promontory (Ligurian Sea) has been investigated, using sets of data collected in 1981 and 1996 respectively. Percent community... more
The structure of a Mediterranean bathyal community living between 400 and 700 m depth in front of Portofino Promontory (Ligurian Sea) has been investigated, using sets of data collected in 1981 and 1996 respectively. Percent community composition, total density and biomass don’t show any significant change, at least on the whole. Although total species number found in the two considered years is comparable, as well as diversity and evenness values, the specific composition shows an almost complete substitution. In particular, the disappearance of epifaunal species, mainly of large size, is outstanding. A real biocoenotical change did not occur, as evidenced by the qualitative (species dominance) and quantitative (numerical dominance) analyses of biocoenotical stocks, which show only a light increase in abundance of limicolous species and species linked to deep muds (VP) versus coastal terrigenous muds (VTC). Conversely, multivariate analysis evidences a clear clustering of 1996 and 1981 data due to presence/absence or different abundance of some key species: Amphilepis norvegica, Spiophanes kroyeri rejssi and Amphiura filiformis are present only in 1981, Aricidea quadrilobata and Paradoneis lyra appear in 1996. The analysis of community trophic structure highlights a significant increase of carnivorous species (mainly scavengers), mostly in terms of numerical dominance, opposed to a strong decrease of deposit-feeders.