Application of biotic and taxonomic distinctness indices in assessing the Ecological Quality Status of two coastal lakes: Caprolace and Fogliano lakes (Central Italy)

Marine biotic indices (AMBI, BENTIX) and the statistical tool M-AMBI (Multivariate AMBI) were applied as a comparative approach in assessing the Ecological Quality Status (EcoQS) of two Mediterranean coastal lakes (Caprolace and Fogliano lakes) situated in the Circeo National Park (Central Italy). The macrobenthic community was analysed using univariate indices (community structure), correspondence analysis (CA) and taxonomic distinctness indices (Delta(+) and Lambda(+)). The community composition showed a dominance of lagoonal species in both coastal lakes, while in Caprolace lake marine taxa were also found. Diversity index (H') complies to ranges found in Mediterranean lagoons and taxonomic distinctness indices demonstrated that taxonomy structure is in accordance with natural variability ranges. Principal component analysis (PCA) on chemical parameters of water and sediment showed that both coastal lakes differ mainly in their organic matter composition. In fact, the protein fraction of bio-polymeric carbon prevails in Fogliano lake, while the 'refractory' component represented by carbohydrate fraction is predominant in Caprolace lake. The difference between the two coastal lakes was also demonstrated by co-inertia analysis (COIA) performed using abundance of species and concentrations of chemical parameters. The results from the application of the three biotic indices do not highlight a clear distinction between the two lagoons. However, the AMBI index provided a more suitable evaluation of EcoQS corresponding to 'slightly polluted' lagoons while M-AMBI and moreover BENTIX indices indicated a worsening situation. The biotic indices are widely used in assessing the EcoQS in marine environments, but their proper application in transitional waters would depend on a resettlement; thresholds established in the biotic index scale values need to be modified according to natural variability of transitional waters referring to abiotic conditions and abundance of tolerant species. (C) 2008 Elsevier Ltd. All rights reserved

Bathymetric and longitudinal distribution analyysis of the rockfish Helicolenus Dactylopterus (Delaroche, 1809) in the southern Tyrrhenian Sea (central Mediterranean)

This study provides information on bathymetric and longitudinal distribution heterogeneity of the rockfish Helicolenus dactylopterus in the southern Tyrrhenian Sea. Data were drawn from experimental bottom trawl (1996-2002) plus bottom trap (2001-02) surveys. The frequency of occurrence and mean relative density (N/km2) and biomass (kg/km2) indexes were calculated for two survey seasons (spring and autumn), four geographic sectors and three depth strata. MANOVA was used to test fish abundance among years, sectors and strata. Analysis of the length-frequency distributions was carried out by two-way (gears and depths) ANOVA, post hoc multiple comparisons for testing differences among depths and Student’s t test for testing differences between gears. Length-weight relationship was also estimated and the allometric coefficient was tested with the Student’s t test. The results showed a significant positive bathymetric gradient of sizes both for trawl and trap surveys; at same depths, fish caught by traps were significantly longer than those caught by trawl. In spring surveys, significant differences were found among strata for both abundance indexes; in autumn surveys, significant differences between depth strata were found only for density indices. The distribution and abundance patterns of H. dactylopterus along the southern Tyrrhenian Sea was homogeneous among sectors. Length-weight relationship showed a significant positive allometric growth

Crustacean fishery with bottom traps in an area of the southern Tyrrhenian Sea: species composition, abundance and biomass

The north-eastern coast of Sicily is characterized by deep, steep bottoms, not easily exploitable by trawl fishery. In this area few fishermen use bottom traps to catch shrimps and Norway lobsters. Our studies were aimed at identifying the species' composition, abundance and biomass of crustaceans exploitable by bottom traps in this area. Monthly samples over one year were obtained from two lines of 30 baited traps each, at depths between 100 and 500 m. One line was placed in an area usually exploited by this fishery; the other line was used in the unexploited deepest bottoms. Trapped specimens were counted and weighed. ANOVA test, post hoc multiple comparisons and Student's t test were applied on abundance and biomass data, for testing differences between areas, among seasons and species. During 22 fishing days, 23 species characteristic of the bathyal mud assemblage were caught, 8 of which were not considered commercial. Plesionika edwardsii was the most important species, recorded in the whole bathymetric range investigated; Nephrops norvegicus was significantly higher in terms of biomass in the unexploited area. The discard, of slight importance, was mostly represented by the crab Liocarcinus depurator. Spring season yielded the best catches in both areas, showing the highest values for both abundance and biomas

Metals in Molluscs and Algae: a North-South Tyrrhenian Sea Baseline.

We develop a 800km long relative baseline of metal pollution for the Tyrrhenian Sea, from the north of Naples to south of Sicily (Italy), based on spatio-temporal (1997–2004) concentrations of trace metals in marine organisms and on the bioaccumulative properties of those organisms. The study concerns sites in the gulf of Gaeta-Formia, near Naples, and three islands north, west, and south of Sicily: Ustica, Favignana and Linosa. The five metals are: cadmium, chromium, copper, lead, and zinc; the species include: Monodonta turbinata (n = 161), Patella caerulea (n = 244) and the algae Padina pavonica (n = 84). We use Johnson’s (1949) [15] probabilistic method to determine the type of distribution that accounts for our data. It is a system of frequency curves that represents the transformation of the standard normal curves. We find an N–S pollution gradient in molluscs considered: the lowest metal pollution occurs around the Sicilian islands. Our method can accurately characterize marine pollution by contributing to: policy-making, coastal resources management, the assessments of environmental damages from marine accidents and other events. The method here presented is a useful tool for pollution comparisons purposes among ecosystems (i.e., risk monitoring) and it is an ideal starting point for its application on a global scale

Intra- and interspecific analysis of first instar larval morphology in the blister beetle genus Berberomeloe Bologna 1989 (Coleoptera: Meloidae)

The first instar larva of Berberomeloe insignis (Charpentier, 1818) is described and figured for the first time and compared to that of B. majalis (Linnaeus, 1758). Diagnostic larval characters of the genus and of both species are identified. Morphometric data from different populations are analyzed statistically. Results support species differentiation and characters definition. Additionally, analyses also suggest that whereas B. majalis is structured in the Iberian Peninsula, there is a lack of differentiation between Iberian and North African populations

Susceptibility assessment of shallow landslides in the Messina province (North-East Sicily, Italy)

A severe rainstorm struck part of the Messina province (NE Sicily, Italy) on October, 1st 2009 and triggered several flash floods and landslides, causing human losses and damages to infra- structures. Landslides, mainly consisting of debris/soil slide—debris flows, involved the thin regolith (thickness 0.3–2 m) which covers the metamorphic bedrock. A detailed landslide inventory map was produced through field surveys and analysis of high resolution aerial orthophotos taken immediately after the event. About 1600scar areas have been identified. The spatial hazard assessment has been focused on the detachment areas and took into account lithology; land cover; morphometric and hydrologic parameters. A preliminary analysis was performed by means of the Frequency Ratio approach. A more detailed analysis was then carried out by adopting a multivariate statistical approach. The two results were compared and the reciprocal similarities and differences were highlighted from both a qualitative and quantitative point of view

Sex and age sensitivity of Tigriopus fulvus (Copepoda, Harpacticoida) towards two heavy metals (Cd and Cu)

The paper reports the results of preliminary toxicity tests monitoring adult and larval stages of T. fulvus survival in presence of two heavy metals (Cu and Cd). Data indicate males as more senisitive than females to presence of both contaminants and nauplii as the most sensitive of all. The ease of culturing and the values of LC50 comparable to those of other test-species suggest the possible use of this meiobenthic crustacean in ecotoxicology studies

Monte Carlo simulations to assess the uncertainty of locating and quantifying CO2 leakage flux from deep geological or anthropogenic sources

Accurately locating and quantifying carbon dioxide (CO2) leakage to the atmosphere is important for diffuse degassing studies in volcanic / geothermal areas and for safety monitoring and/or carbon credit auditing of Carbon Capture and Storage (CCS) sites. This is typically conducted by measuring CO2 flux at numerous points over a large area and applying statistics or geostatistical interpolation. Accuracy of the results will depend on many factors related to survey/data-processing choices and site characteristics, and thus uncertainties can be difficult to quantify. To address this issue, we have developed a Monte Carlo-based program (MC-Flux) that repeatedly subsamples a high-resolution synthetic or real dataset using a choice of different sampling strategies (one random and four grid types) at multiple user-defined sample densities. The program keeps track of the anomalies found and estimates total flux using two statistical and two geostatistical approaches from the literature. This paper describes the use of MC-Flux to assess the potential impact of various sampling and interpretation decisions on the accuracy of the final results. Simulations show that an offset grid sample distribution yields the best results, however relatively dense sampling is required to obtain a high probability of an accurate flux estimate. For the test dataset used, ordinary kriging interpolation produces a range of flux estimates that are centered on the true value while sequential Gaussian simulation tends to slightly overestimate values at intermediate sample spacings and is sensitive to input parameters. These results point to the need for developing new approaches that decrease uncertainty, such as integration with high-resolution co-kriging datasets that complement the more accurate point flux measurements

Intra- and interspecific analysis of first instar larval morphology in the blister beetle genus Berberomeloe Bologna 1989 (Coleoptera: Meloidae)

The first instar larva of Berberomeloe insignis (Charpentier, 1818) is described and figured for the first time and compared to that of B. majalis (Linnaeus, 1758). Diagnostic larval characters of the genus and of both species are identified. Morphometric data from different populations are analyzed statistically. Results support species differentiation and characters definition. Additionally, analyses also suggest that whereas B. majalis is structured in the Iberian Peninsula, there is a lack of differentiation between Iberian and North African populations