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(Uploaded by Plazi for the Bat Literature Project) The evolutionary history of plant and animal species has been deeply influenced by both climate changes and human actions. Human actions have been particularly heavy during the Anthropocene, when over 250 mammal species became extinct, mostly on islands. Here, we shortly review the existing literature, and test whether the various mammalian orders are all equally prone to extinction risks. We concluded that species belonging to the orders Rodentia, Primates, and Artiodactyla were more prone to become extinct, whereas those belonging to the orders Chiroptera and Carnivora were less. Surprisingly, apparently IUCN red list placed higher conservation concerns for the species belonging to the mammalian orders which are globally least prone to become extinct during the Holocene.

AbstractThis study had the objective of quantifying the variability in abundance, cell volume, morphology and C content of a natural bacterioplankton community in a coastal zone of the North Adriatic Sea during two periods (February and June) of two consequent years (1996 and 1997). We used epifluorescence microscopy with Acridine Orange staining procedures and a microphotographic technique. Low variability in bacterial abundance (range 0.3–3.1 × 105 cells ml−1) occurred between summer and winter periods. Conversely, the cell volume and the calculated carbon content changed greatly with warm and cold periods (ranges: 0.015–0.303 μm3 and 5.83–42.17 fg C cell−1, respectively). Elongated bacteria were dominant while coccoid cells prevailed only in February 1997. Biomass showed high variability (range 0.12–10.21 μg C l−1) whilst the abundance did not show noticeable differences among the sampling periods. As a consequence, quantification of bacterial biomass based solely on cell abundance must be considered with caution because the true biomass could depend on variability in cell volumes and morphotypes.

This paper presents energy and power evaluations on propulsion and generation systems related to a research vessel, named G. DALLAPORTA. This vessel is used by the National Research Council of Italy for oceanographic campaigns, which are generally carried out in the Mediterranean Sea. The analysis is based on measurements of the main electrical and mechanical parameters, related to on board propulsion, oleodynamic and electric auxiliary systems, with reference to the original thermal configuration of the ship. These preliminary results, obtained through theoretical methodology, make possible the identification of a designing procedure for the hybridization of this vessel, in order to respect the international marine standards, in terms of emissions and safety procedures.

Deep lakes south of the Alps (DSL: Maggiore, Lugano, Como, Iseo and Garda) are characterised by varying trophic states and dissolved oxygen (DO) concentrations. Some of these lakes experience anoxic conditions in deep waters. We hypothesised that the increase in temperature and water-column stability observed in these lakes during recent decades influenced the deep-water DO concentration. In particular, we tested whether the thermal regime of the lakes and the depth of mixing affect oxygen replenishment during winter-spring turnover. To this aim, we analysed long-term trends and seasonal variability of oxygen levels in the DSL during 1992-2016. We included in our analysis the effects of environmental variables, such as winter air temperature and atmospheric modes of variability. Our results showed a recent decrease in the deep-water oxygen content in lakes Maggiore, Como and Garda and an increase of the extent of anoxic conditions in lakes Lugano and Iseo. Our results suggest that, beside cultural eutrophication, rising environmental pressures, such as global warming, can influence the future trends of the oxygen levels and ecological states of deep lakes.

Concern for load analysis and structural design of offshore renewable energy devices. Attention shall be given to the interaction between the load and structural response of fixed and floating installations taking due consideration of the stochastic nature of the ocean environment. Aspects related to prototype testing and certification shall be considered

Due to the poor state of the fishery resources, trawlers are not profitable as they use to be. One way of improving their profitability is to reduce operational costs, especially by reducing fuel consumption. A number of fishing vessels is not efficient usually because of their outdated technology. Due to the European Commission restraints to new constructions, the major opportunities for reducing fuel consumption are chiefly related to an improvement of the vessel's propulsion systems. A technical feasibility of a new propulsion system architecture have been studied in 2008 through a research funded by the European Community (EC Regulation 2792/99, Article 17 - Innovative measures. n.27/IM/06 Project). In the propulsion system herein proposed, the overall power required by the vessel is subdivided in multiple power units, each one obtained by coupling a diesel engine with a permanent magnet brushless electric generator, while the propeller is coupled with an electric motor. Trough an electronic management system, it is possible to maintain one or more power units at different operating points to guarantee the minimum overall fuel consumption. In this study two power units have been considered. Many load tests have been done on a marine diesel engine, to evaluate its fuel consumption, torque and power delivered against the revolution speed. An algorithm to control the power units have been obtained from experimental data. The carried tests demonstrated the so conceived propulsion system as really reliable. A fuel saving of up to 15% was achieved with a power units equipped with a 257 kW @ 3800 rpm diesel engine. The proposed propulsion system could be useful both in new vessel and for a re-dumping of existing vessels. Further advantages are related to the possibility to avoid propeller shaft and reduction gear, then reducing weights, noise and pollution.

Farming of shellfish and seaweeds is a tested tool for mitigating eutrophication consequences in coastal environments, however as many other marine economic activities it should be a subject of marine spatial planning for designating suitable sites. The present study proposes site selection framework for provisional zebra mussel farming in a eutrophic lagoon ecosystem, aimed primarily at remediation purposes. GIS-based multi-criteria approach was applied, combining data from empirical maps, numerical models and remote sensing to estimate suitability parameters. Site selection and prioritisation of suitable areas considered 15 environmental and socio-economic criteria, which contributed to 4 optimisation models (settlement, growth and survival of mussels, environmental and socio-economic) and 3 predefined scenarios representing provisional goals of mussel cultivation: spat production, biomass production and bioremediation. The relative importance of each criterion was assessed utilizing the Analytical Hierarchy Process. Site suitability index was calculated and the final result of the site selection analysis was summarized for 3 scenarios and overall suitability map. Four suitability classes (unsuitable, least, moderately and most suitable) were applied, and 3 most suitable zones for provisional zebra mussel cultivation with 12 candidate sites were selected accordingly. The integrated approach presented in this study can be adjusted for designating zebra mussel farming sites in other estuarine lagoon ecosystems, or cultivation of other mussel species for bioremediation purposes. The analytical framework and the workflow designed in this study are also adoptable for addressing other aquaculture-related spatial planning issues.

Freshwater fish communities are impacted by multiple pressures, determining loss of functional diversity and redundancy. Our aim was to disentangle the roles and relevancies of different pressures in shaping fish communities in small streams of the Po plain (North Italy). Long term trend (1998-2018) of functional diversity of 31 fish communities was assessed and modeled in respect to three potential pressures: temperature increase, intensity of exotic fish invasion, and habitat quality degradation. Ecological traits mostly influenced by the pressures were also identified. Reduction of functional richness mostly due to local extinction or contraction of cold adapted predators, such as salmonids, was linked to increasing temperatures. Warming probably also led to a shift of generalist and dominant species, which became more abundant in streams hosting mixed communities of salmonids and cyprinids, and determined the increase of functional dispersion and uniqueness. Reduction of functional redundancy and increasing functional dispersion were both also related to the introduction of new ecological traits brought by expanding exotic species. Low functional overlap was found among native and exotic species, indicating that the invasion process was mainly controlled by competitive interactions and/or resource opportunism. Functional response to habitat quality was not clearly evident. In conclusion, the impact of temperature increase and exotic species on fish functional diversity was effective, idiosyncratic and mediated by the scale of analysis and by the intensity of pressures.