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Cystoseira sensu lato marine forests, which are among the most productive and diverse systems in rocky intertidal and subtidal habitats of the Mediterranean Sea, are experiencing a widespread decline throughout the basin due to increasing human pressures. Yet it is still unclear whether Marine Protected Areas (MPAs) may represent effective tools for conservation of these important habitat formers and their associated assemblages. Here, we compared the biomass of intertidal stands of Ericaria amentacea (C. Agardh) Molinari and Guiry and their understory assemblages between the no-take zone and control sites in two Mediterranean MPAs. We did not find evidence supporting a significant effect of full protection in increasing the biomass of E. amentacea stands and associated assemblages, except for macroalgae of the understory in one of the investigated MPAs, raising concerns on the potential effectiveness of MPAs in mitigating human impacts on these marine forests. Such findings call for major efforts to implement long-term monitoring programs of protected Cystoseira s.l. forests in order to inform an adaptive management of conservation measures within MPAs and eventually to set active interventions of restoration.

Assessing the effects of pollution in groundwaters is recently considered among the most relevant aims for subterranean biology; with this perspective, we aim to provide examples of the most relevant effects that pollution may cause on stygofauna community and underline patterns deserving further investigations. We retrieved different cases in which pollution caused alteration of groundwater trophic webs, favored invasions by epigean mesopredators, damaged stygobiont keystone species, and promoted interspecific competition between stygobionts and epigean animals. The results and the remarks derived from our perspective review underline that pollution may play multifaceted effects on groundwaters communities, and the paucity of information that exists on community-level changes and threats underlines the necessity for further studies.

Alpine lakes are among the most remote aquatic environments in Europe. Although remote, their small size and the high turnover of surface waters render alpine catchments extremely receptive and vulnerable to anthropogenic impact on a local (i.e., water abstraction, tourism, introduction of alien species) and a global scale (long-range transport of pollutants, acid rain, global warming). Alpine lakes are indicators of global environmental change and “early warning systems” for the mountain environment. Many studies have considered single lakes or groups of lakes; however, because of the wide extent of the Italian Alpine area together with the difficulty of sampling, there have been few studies of the Alpine lakes as a whole. Since it was not possible to extend the research to all Italian Alpine lakes, two lakes (Balma Lake, Cottian Alps, 2100 m a.s.l. and Dimon Lake, Carnic Alps, 1872 m a.s.l.) were selected for this study according to the following criteria: a) the geographic location of the research groups involved in the project, Department of Life Sciences, University of Trieste and Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle d’Aosta; b) site geomorphology and accessibility; 3) presence of fish after introduction for recreational fishing. The main aims of this PhD project were: a) conduct ecological characterization based on biotic components (macrobenthic invertebrates, benthic diatoms, ostracods and fish); b) study the pressures and changes via analysis of biotic components; c) obtain background data for future research. The overarching objectives were: 1) obtain topographic and bathymetric maps of lakes using new technologies (drones); 2) characterize the hydrochemistry; 3) characterize macrobenthic invertebrates, benthic diatoms and ostracods since typical biological components of Alpine lakes and widely used to assess ecological status of surface freshwater; 4) investigate changes in chironomids, ostracods and benthic diatoms composition over time based on paleolimnological analysis. These biological components can yield information to different perturbations and, given a good time-control, it is possible to estimate phases and amplitudes of disturbance; 5) investigate environmental contamination through trace elements detection in macrobenthic invertebrates; 6) characterize fish communities, obtaining information about their biological and sanitary condition. Sampling was performed during the ice-free season (summer and autumn of 2017 and 2018) at both lakes. The physicochemical features of the lakes were in line with published literature but differed from each other due to the geo-lithological context of the two areas. The biodiversity of the littoral macrobenthic communities was comparable with other high-altitude environments, where Diptera Chironomidae and Oligochaeta generally predominate. Paleolimnological analysis of Balma Lake highlighted significant differences in subfossil chironomid communities before and after the introduction of fish and between modern and subfossil communities, with a significant reduction in diversity. Macrobenthic invertebrates from the two lakes were found to differ in trace element concentration, which was higher in Dimon Lake. Individuals of bullhead (Cottus gobio) and minnow (Phoxinus phoxinus) were captured from Dimon Lake, whereas only brook trout (Salvelinus fontinalis) were captured from Balma Lake, with individuals belonging to age classes 0+ to 4+. Health monitoring revealed hepatic steatosis in C. gobio from Dimon Lake, probably linked to an adaptation of the fish to the winter season. Finally, the analysis of benthic diatoms and ostracods is preliminary, and the results need to be further elaborated and developed in the future. This PhD thesis has produced new data about the ecology and conservation status of two Alpine lakes, which may guide local administrations in their decisions to implement conservation and monitoring plans.

The aim of the study is to provide a synthesis on the biodiversity of zoobenthic species and benthic habitat distribution of Site of National Interest (SNI) of Bagnoli-Coroglio (Gulf of Naples, Tyrrhenian Sea, Italy), which represents one of the priority areas selected at National level for habitat restoration, and is located within the Gulf of Pozzuoli (a large Bay at the northern part of the Gulf of Naples). The work provides a dataset, covering the entire Gulf of Pozzuoli, and obtained consulting several sources of information, from historical to recent publications, and grey literature, aimed at the production of a check-list of species, and reconstruction map of the main marine habitats, in order to achieve a synoptic overview of the historical and recent zoobenthic fauna, as well as distribution of habitats, in order to serve as reference point for any future restoration plan in the area. Relevant information regarding the study area was found in 67 out of more than 250 sources consulted. Overall, 813 species of benthic organisms were recorded, summing up a total of 1006 records. Among them, 148 species were reported in the pre-industrial period (prior to 1911), 361 species during the industrial period (from 1911 to 1991), and 381 species in the course of the post-industrial period (from 1992 up to the present day). No differences in biodiversity or distribution of individual species were directly attributable to the industrial activities in the study area. Such a finding is possibly due to different sampling effort among periods and lack of quantitative data for the majority of the recorded taxa. A mosaic of various habitat and biocoenoses were documented in the zones (shallow and deep hard bottoms, soft-bottoms with different sediment types, seagrass meadows). An overall reduction of the cover and a higher habitat fragmentation was documented for seagrass meadows (mainly Posidonia oceanica) over time. Given that regression of this seagrass species is common in a much wider extent than that covered by the study area, the trend here observed is probably due to multiple impacts from different human activities, including the industrial one at the Bagnoli SNI. The present study highlights that the SNI area is placed in a wider area representing a mosaic of different habitat types, which can provide donor populations of both habitat formers (sponges, gorgonians, scleractinians, bryozoans and mollusks), and seagrasses. These organisms are potentially relevant in implementing restoration measures aimed to improve the ecological status of this post–industrial area.

Understanding which drivers cause diversity patterns is a key issue in conservation. Here we applied a spatially explicit model to predict marine benthic diversity patterns according to environmental factors in the NW Mediterranean Sea. While most conservation-oriented diversity studies consider species richness only and neglect equitability, we measured separately species richness, equitability, and 'overall' diversity (i.e., the Shannon-Wiener H' function) on a dataset of 890 benthic species × 209 samples. Diversity values were predicted by means of Random Forest regression, on the basis of 10 factors: depth, distance from the coast, distance from the shelf break, latitude, sea-floor slope, sediment grain size, sediment sorting, distance from harbours and marinas, distance from rivers, and sampling gear. Predictions by Random Forests were accurate, the main predictors being latitude, sediment grain size, depth and distance from the coast. Based on predicted values, diversity hotspots were identified as those localities where indices were in the 15% top segment of ranked values. Only a minority of the diversity hotspots was included within the boundaries of the protection institutes established in the region. Marine protected areas are often created in sites harbouring important coastal habitats, which risks neglecting the diversity hidden in the sedimentary seafloor. We suggest that marine protected areas should accommodate portions of sedimentary habitat within their boundaries to improve diversity conservation.

Coastal power plants generally use seawater as cooling fluid, discharging heated waters into the sea after the cooling process. The ensuing increase in seawater temperature could affect the marine biota in the nearby areas, causing alterations at different level of biological organization, from individuals to populations and assemblages. In the Mediterranean Sea, few attempts have been made to assess the effects of this point sources of thermal pollution, especially on rocky habitats. Here, we investigated the putative impact of a thermal effluent from one of the largest European coal-fired coastal power plants on sessile assemblages of subtidal rocky reefs. Sessile assemblages on rocky substrates were photographically sampled at one location near the effluent ( I ), and at two control locations ( Cs ) virtually unaffected by thermal discharge. An asymmetrical after-control impact experimental design was employed to test the hypothesis that the thermal discharge significantly modified sessile assemblages at I if compared to Cs . We detected significant differences in assemblages at I versus Cs , indicating a clear effect of the effluent on assemblage structure. Such differences were mostly due to shift in dominance among macroalgae between I and Cs , which likely depended on different tolerance limits of species to increased seawater temperature and other sources of disturbance associated to the effluent, such as increased sedimentation rates and water turbidity. Our findings stressed the need for further investigations of the impact of thermal effluents on marine communities, considering the potential synergistic effects of climate change especially in the Mediterranean Sea.

Biodiversity is a multidimensional concept encompassing many scales of variation, originally partitioned into three components: alpha, the number of species in a single sampling unit, beta, the variation in species identities from site to site, and gamma, the overall number of species within a defined geographical area. Investigations on macrobenthic assemblages in transitional waters have been traditionally focused on alpha- and gamma-diversity, largely neglecting beta-diversity. The aim of the work was to identify patterns of variation of macrobenthic invertebrates in transitional waters from 18 different Italian lagoons (central Mediterranean) at three different scales (site, lagoon and region), combining classical and multivariate measures for partitioning diversity. Classical alpha, beta and gamma diversity were calculated, together with measures considering also relative species abundances. The highest variability of macrobenthic assemblages was observed at the intermediate scale (among lagoons), with significant variations in terms of both alpha and beta diversity. At the smallest analysed scale (among sites) the variability was mainly in terms of beta diversity, whereas at the biggest scale (among regions), the variability was mainly in terms of alpha diversity. At the intermediate scale (among lagoons) alpha diversity was influenced by the regional species pool, with one exception (Grado-Marano lagoon) where the habitat heterogeneity and beta diversity played a major role. Beta diversity, measured as variability of dispersion with Jaccard resemble measure, was consistent with results obtained with the original formulation of Whittaker. Considering alpha diversity, a different pattern of variability was observed considering relative abundances, whereas considering beta diversity, no significant differences were observed in terms of relative species abundances. The patterns of macrobenthic assemblages among lagoons in terms of both alpha and beta diversity resulted from the complex interaction of different drivers acting in a framework of geographical variability. Alpha diversity was mainly influenced by salinity, but other factors (size, confinement, trophic status and sediment composition) were likely to contribute. Beta diversity was mainly influenced by habitat heterogeneity, deriving from different environmental parameters, such as trophic condition and water confinement. Our results support the usefulness of portioning diversity in alpha, beta and gamma components, and of combining different univariate and multivariate measures of dispersion, to consider patterns of richness and relative abundances separately.

Wrecks play an important role in enhancing marine biodiversity. SCUBA diving video-samplings were performed on eight wrecks, including seven shipwrecks and a sunken airplane, scattered over 180 km along the Ligurian coastline in the northwestern Mediterranean Sea, in water depths of 30‐65 m. Differences in composition of macrobenthic communities were found to be related to the bottom sedimentology and the composition and geometry of the investigated structures. The iron, flat, and even substrata of shipwrecks were dominated by Bivalvia (Ostrea edulis) and Anthozoa (Corynactis viridis), whereas the aluminum, cage-like structure of the airplane was dominated by massive sponges and bryozoans. Furthermore, abundances of some macrobenthic invertebrates were greater on the wrecks than those observed on natural, rocky substrates. Because of the increasing popularity of use of video and photo digital apparatuses among recreational divers, combined with wreck resistance to corrosion, artificial geometries and available surfaces that facilitate species’ settlement and growth, data from wrecks consisting of images and related metadata (depth, date, water temperature, etc.) could provide a new opportunity for monitoring Mediterranean marine biodiversity.

12 pages, 4 figures, 5 tables, The long-term benthic disturbance experiment (BENDEX) was started on the eastern Weddell Sea shelf off Austasen (Antarctica) during ‘Polarstern’ cruise ANT XXI/2 in December 2003 to simulate the impact of grounding icebergs on the seabed and follow the steps and timescales of recovery of disturbed benthos and demersal fish communities. Here, we report the basic approach and first results for this experimental field study. By means of 11 densely-placed hauls with a modified bottom trawl, a seabed area of approximately 100 × 1000 m was artificially scoured to inflict a similar damage to the benthic habitats as a grounding iceberg. Before the disturbance event and 11 days after it, the seafloor communities were sampled (invertebrate assemblages by multibox corers, the fish fauna by trawl hauls) and comparatively analyzed. Sediment texture and chemistry was not significantly altered by the heavy disturbance inflicted by repeated trawling, whereas the fauna was negatively affected. Invertebrate benthic biomass was drastically reduced by a factor of 10, while mean abundances were only slightly reduced. Demersal fish biomass and abundance were slightly but not significantly smaller after the disturbance. Effects of disturbance became more evident in the composition of the fish fauna, with Trematomus pennelli and T. hansoni being dominant at disturbed sites, whereas Chionodraco myersi was the dominant species in trawl catches from undisturbed stations

The impact of pesticides on macrobenthos communities was studied on two aquatic environments in Northern Italy; River Meolo, a site exposed to agricultural pollution, and River Upper Livenza a low pollution reference site. Colonisation of artificial substrates was compared throughout the productive season. The relevance of multiple environmental stressors other than pesticides (e.g. oxygen depletion) was also assessed. Biochemical indicators (enzyme and metabolite biomarkers) were measured on selected organisms. Biomarker results (acetylcholinesterase, glutathione S-transferase, and napthylacetate esterase), as well as community structure patterns, revealed a significant difference between the two rivers. Cause-effect relationships between results and multiple stress factors were discussed. © 2008.