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The effect of oxidation on nascent soot particles is investigated in this work by means of Raman spectroscopy. Three different soot particle samples are produced in a lightly sooting ethylene/air laminar premixed flame and collected at different residence times. The samples are characterized by a different size of primary particles and a different degree of aging and hence graphitization, and they are representative of the early evolution of nascent soot in flames. Oxidation of particles is induced by exposing the samples to a high temperature oxidation treatment in air over a range of temperature 25–500°C. To this aim, a programmable heating microscope stage is used. Thermo-optical transmission (TOT) measurements are used to characterize the chemical composition of pristine particles in terms of organic and elemental carbon content, also providing the pyrolytic carbon fraction of the organic carbon. The TOT results show that the organic fraction is constant for the three conditions. On the other hand, the pyrolytic carbon fraction decreases and the elemental carbon increases when moving from the sample composed of just-nucleated particles to the sample mostly made of mature soot particles. Raman spectroscopy reveals that the thermal oxidation treatment performed on the sample of just-nucleated particles, with the highest organic carbon content, results in a reduction of the amorphous carbon component. Conversely, the sample of mature soot, with the highest elemental carbon content, shows an increase in the amorphous carbon phase after oxidation, which is attributed to fragmentation or the formation of point defects by O2 oxidation. Finally, the thermal oxidation procedure produces a strong reduction in the photoluminescence signal detected from Raman spectra.

Flame-formed just-nucleated carbon nanoparticles, with sizes of about 2-10 nanometers, have been the object of increasing interest over the last decades not only because of environmental concerns but also as new procedure for synthesis of engineered nanoparticles. In this work, we present an experimental study on synthesis and characterization of carbon nanoparticles generated in a laminar premixed ethylene/air flame. The production of carbon nanoparticles of different sizes and properties is achieved by changing the particle residence time in the flame, i.e., collecting the carbon nanoparticles at different heights above the burner. Particle size distributions, Raman, UV-visible and electron paramagnetic resonance (EPR) spectroscopies have been used to characterize the sampled particles. The size of the particles increases as the residence time in the flame increases, the particle size distributions changing from a unimodal to bimodal. Chemical and structural modifications are retrieved by Raman and EPR analysis. Raman spectra show the G and D bands, typical of disordered carbonaceous materials. Their relative intensity and band position changes during the growing process and are used as index of structural changes. EPR spectroscopy, a powerful tool to probe electronic properties of carbon-based materials, reveals the presence and superposition of multiple paramagnetic species. Persistent carbon-centered aromatic radicals are detected for all the sampled particles and an abrupt change in the EPR signal is observed as the particle distribution changes from monomodal to bimodal. EPR indicate a three-dimensional structural organization when larger particles are formed. Optical proprieties are retrieved by UV-visible spectroscopy which, combined to Raman and EPR spectroscopy, seems to be powerful diagnostics to monitor particle clustering and to control the process of engineered carbonaceous nanoparticle production.

Natural processes and human activities are strongly connected, and sometimes con icting, in the evolution of coastal and transitional environments. The strong anthropic pressure on coastal regions, together with the e ects of a changing climate, demands nowadays more pressingly for e cient tools to characterise and predict the behaviour of such systems in order to de ne appropriate response strategies. This requires a deep understanding of the connections among di erent drivers and di erent scales, a multidisciplinary challenge in which heterogeneous data, approaches and scales need to be framed within a consistent dynamical description. To this aim, a speci c research line was dedicated to “Coastal Vulnerability to Erosion and Sea Level Rise” within the RITMARE Project, supported by the Italian Ministry of University and Research with the purpose of integrating the Italian Marine community in shared research elds in the period 2012-2017. The activities carried out in this framework have been moving along interconnected branches tackling the themes related with sea level rise, ocean modelling, and geomorphological assessment in present conditions and in di erent climate change scenarios, with an eye on the exploitation of marine sand as a strategic resource. In this contribution we review the main outcomes of this multidisciplinary and coordinated research. Besides discussing the advances and the possibilities from state-of-the art technologies and methodologies, we point out that a coordinated use of the described tools should be promoted in the design of survey and monitoring activities, as well as in the exploitation of already collected data. Expected outcomes of this strategy include the implementation of improved policies and infrastructures for coastal protection, anked by reliable short-term forecasting systems and e cient rapid response protocols, in the framework of an integrated coastal planning at the multi-decadal scale.

We depict the relative sea-level rise scenarios for the year 2100 from eight areas of the Italian peninsula. Our estimates are based on the Rahmstorf (2007) and IPCC-AR5 reports 2013 for the RCP-8.5 scenarios (www.ipcc.ch) of climate change, adjusted for the rates of vertical land movements (isostasy and tectonics). These latter are inferred from the elevation of MIS 5.5 deposits and from late Holocene sea-level indicators, matched against sea-level predictions for the same periods using the glacio-hydro-isostatic model of Lambeck et al. (2011). We focus on a variety of tectonic settings: the subsiding North Adriatic coast (including the Venice lagoon), three tectonically stable in Sardinia coastal plains (Oristano, Colledonia and Cagliari coastal plain), Marche (Tronto), Abruzzo (Pescara and Sangro coastal areas), Apulia (Lesina), Granelli (Sicily), and Marina di Campo (Tuscany) and the slightly uplifting Taranto coastal plain. Maps of ooding scenarios are shown on high-resolution Digital Terrain Models mostly based on Lidar data. The expected relative sea-level rise by 2100 will change dramatically the present-day morphology, potentially ooding up to about 6000 km2 of coastal plains at elevations close to present-day sea level. The subsequent loss of land will impact the environment and local infrastructures, suggesting land planners and decision makers to take into account these scenarios for a cognizant coastal management. Our method developed for the Italian coast can be applied worldwide in other coastal areas expected to be a ected by marine ingression due to global climate change.

The increasing awareness of the potential threats acting on the coastal regions, combined with the intense anthropic pressure and the broad variety of socio-economic drivers acting on these systems, bestowed progressively stronger emphasis to the development of sound planning and management policies. The assessment and the formulation of plans for the response to coastal morphological vulnerability is a multidisciplinary challenge, in which different typology of information, approaches and scales need to be integrated and framed within a consistent dynamical description. To this aim, within the RITMARE National Flagship Project, a specific research line on “Coastal Vulnerability to Erosion and Relative Sea level rise in climate change scenarios” was activated with reference to the Adriatic-Ionian region (Eastern Mediterranean Sea). The activities, supported by the Italian Ministry of University and Research 2016-18, move along three interconnected branches, namely: 1) Assessment of vulnerability to relative sea level rise in the Adriatic-Ionian region, in present conditions and in different climate change scenarios; 2) Development of high-resolution oceanographic modelling tools for the description of meteo-marine climate and sediment transport at different scales and rapid response intervention protocols for the evaluation of the impact of erosive events on sandy sediments; 3) Identification of possible geomorphological setting scenarios and definition of intervention strategies, with special care to the exploitment of marine sand as a strategic resource. The work provides an overview of the strategy underlying the Research Line and present preliminary results and main achievements. Next steps will be aiming to pave the way towards a road map for an integrated observational and modelling approach for monitoring and managing the erosion and marine ingression risk throughout Italian coasts, striving to bridge the cultural and methodological gaps between the scientific and administrative sectors active in the coastal management field.

The Spatial Data Infrastructures (SDI) are a critical component of Maritime Spatial Planning to provide a means to preserve and share geospatial data. Objective of the work is to create a geospatial database to data repository and integration of abiotic/biotic variables, anthropogenic pressures, habitat and species distribution patterns by means of the software suite Geoinformation Enabling Toolkit StarterKit (GET-IT), developed by researchers of the National Research Council for RITMARE project. GET-IT facilitates the creation of distributed nodes of an interoperable SDI and enables unskilled researchers from various scientific domains to create their own Open Geospatial Consortium (OGC) standard services for distributing geospatial data, observations and metadata of sensors and datasets. Specifically, this work focuses on the case study of sea urchin fishery management in the "Penisola del Sinis - Isola di Mal di Ventre" Marine Protected Area (herein after "Sinis MPA"). This topic was a key example considering that: (1) Paracentrotus lividus is one of the most intensively exploited invertebrates in Sardinia and a key grazer able in shaping the structure of sublittoral assemblages; (2) there are more restrictive rules governing its exploitation inside the reserve even if the MPA is characterized by low levels of legal compliance and enforcement (3) there is wide availability of spatial and temporal data coming from three different institutions (i.e. Sinis MPA, IAMC-CNR, IMC). The products of the present work are the creation of an information system on the sea urchin resource through interoperable tools allowing the data storage in several levels of information, their sharing integrated management and analysis. This tool, facilitating the understanding of the ecological processes and offers an means to discuss with local stakeholders ways to increase the management effectiveness of biological resources and the individuation of possible policy solutions.

A critical component of Maritime Spatial Planning is the establishment of well-curated, federated Spatial Data Infrastructures (SDI) to provide a means to preserve and share geospatial data while promoting attribution and acknowledgement of its use. Objective of the work is to create a geospatial database of geomorphology, seismic and sedimentology data of Western Sardinian (Italy) marine sector, to share them and to promote planning actions in relation to the management of submerged sand deposits situated in the continental shelf, which can be used for beach nourishment. The work was realized through the integration of data and information collected during several projects. The available data consist of morphobatimetric data (multibeam) associated with the morphoacustic data between -50 and -700 m and singlebeam surveys in low-depth coastal areas. Extensive coverage of high-resolution seismic profiles (Chirp 3.5 kHz) and hundreds of kilometres of sparker profiles were acquired along the continental shelf. Surface sediment sampling (Van Veen grab and box corer) and vibrocorer survey were performed. These data allowed the mapping, determination of the thickness and volumes of the submerged sand deposits and their sedimentological characterization. All data were organized by means of the software suite Geoinformation Enabling Toolkit StarterKit ® (GET-IT), developed by researchers of the National Research Council for RITMARE project. GET-IT facilitates the creation of distributed nodes of an interoperable SDI and enables unskilled researchers from various scientific domains to create their own Open Geospatial Consortium (OGC) standard services for distributing geospatial data, observations and metadata of sensors and datasets. The products of the work are the creation of an information system of the sand reservoir along the Western Sardinian continental shelf through interoperable tools allowing the data storage in several levels of information, their sharing, and integrated management and analysis.