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Abstract: Sandy beaches along the Ligurian coast (NW Mediterranean Sea) are here studied through thermodynamic and network analyses aiming at the identification of typical ecological features of transitional environments. A general model of sandy Ligurian beaches microbenthic loop subsystems is here proposed taking into consideration the across beach gradient spatial variation. Results revealed highest values of activity, complexity, diversity and organization in the swash zone. This makes the swash zone a peculiar and fragile sub-system in the context of sandy beach ecosystems highly adapted to severe environmental constraints. Swash zone is thus here considered as a specific sub-system where the low resource availability and the oscillating environmental parameters (e.g. temperature, dryness, wave physical action) allow only the highly evolved and adapted organisms to survive. [Copyright &y& Elsevier]

A methodology based on emergy analysis for the calculation of the biophysical value of the stocked biomass (natural capital) was applied to the Marine Protected Areas (MPAs) of Portofino (PF) and Cinque Terre (CT). The resources exploited, on a yearly base, to maintain the natural capital itself alive (environmental flows) were accounted too. Emergy analysis is an accounting method useful to identify and convert in a single unit of measure all resources feeding a system. This allows the implementation of a system overall assessment and then the conversion of the obtained value in money terms. The studied MPAs are located in the northwestern part of Italy, are both tourism oriented and subdivided in zones with different protection degree. The habitats occupying both the MPAs bottoms have been identified together with the biomass stored on their surface, identifying units named FBHA (fishes and benthos habitat assemblage). The calculation of biomass stocked in the benthic organisms and in the fishes associated to each FBHA represents the basis for the assessment of MPA natural capital value and of environmental flows. From these values, the trophic network of each habitat was modeled allowing calculating the inputs to emergy analysis. The value of PF natural capital, expressed as resources employed through space and time to store the existing biomass, is equal to over 10 million Euros while the CT natural capital amounts to over 30 million. The high value habitats, where biomass is concentrated and stored, represent hot spots that are restricted in a limited surface and that can be maintained only if the resources they need are provided by adjacent lower value habitats. Through the applied methodology, a balance is performed to understand if an MPA is self-sufficient or dependent on external areas. Therefore, if an MPA is correctly planned, as CT is, the wider low value areas are able to provide resources to the deficit FBHAs and even to export resources to other systems. In this case, the MPA lies in a surplus condition. On the contrary, the MPA is not able to maintain itself and depends on external systems not subjected to protection and then potentially posed at risk. If information about natural capital, flows and balance is synthesized in a Geographical Information System, it represents an effective tool to MPAs managers to measure the efficacy of protection established. [ABSTRACT FROM AUTHOR]

The recent invasion of Callinectes sapidus in the Lesina Lagoon has raised great concern about its potential impacts on the ecosystem and on local fisheries. The effects of the blue crab presence on the receiving ecosystem were evaluated from both a donor-side perspective, through the application of emergy analysis, and a user-side perspective, by means of interviews to the local fishermen. While emergy analysis showed that C. sapidus brings to an increase of both natural capital and ecosystem functions values, results from interviews highlighted that the major problem caused by the presence of the blue crab in the lagoon concerned the local economy. As the first quantitative assessment of the ecological and economic impact of C. sapidus in invaded habitats, the present investigation provided original and useful information for a comprehensive risk assessment of the species in European waters and in Mediterranean Sea., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier Ltd.)

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., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Habitat modeling is an important tool to investigate the quality of the habitat for a species within a certain area, to predict species distribution and to understand the ecological processes behind it. Many species have been investigated by means of habitat modeling techniques mainly to address effective management and protection policies and cetaceans play an important role in this context. The bottlenose dolphin (Tursiops truncatus) has been investigated with habitat modeling techniques since 1997. The objectives of this work were to predict the distribution of bottlenose dolphin in a coastal area through the use of static morphological features and to compare the prediction performances of three different modeling techniques: Generalized Linear Model (GLM), Generalized Additive Model (GAM) and Random Forest (RF). Four static variables were tested: depth, bottom slope, distance from 100 m bathymetric contour and distance from coast. RF revealed itself both the most accurate and the most precise modeling technique with very high distribution probabilities predicted in presence cells (90.4% of mean predicted probabilities) and with 66.7% of presence cells with a predicted probability comprised between 90% and 100%. The bottlenose distribution obtained with RF allowed the identification of specific areas with particularly high presence probability along the coastal zone; the recognition of these core areas may be the starting point to develop effective management practices to improve T. truncatus protection., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

The environmental sustainability of a fish farm rearing process was examined by means of emergy analysis. Many emergy analyses integrate data for a whole year smoothing short term variations and sometimes losing meaningful information (aliasing). For this reason we developed a model for an instantaneous emergy evaluation in an aquacultural system so that transformities, efficiency and effort spent at each moment during the fish rearing activity could be calculated. By means of the model and dynamic emergy calculations it is possible to recognize step by step the importance of the various emergy contributions and verify where and when to modify the system to move toward optimum production of a sustainable product. By the application of the model we confirmed that the emergy trends in a fish farm installation follow wide oscillations during a year due to variations in both internal and external emergy contributions. Among the fluxes considered, those due to the introduction of fingerlings represented the highest contributions to the total emergy budget. Thus, to improve the sustainability of the analyzed system the amount, frequency and timing of these fluxes must be carefully considered. For this purpose, a comparison between two different fry introduction schedules was performed to evaluate differences in the efficiency of the rearing process.