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Beaches can serve as a valuable asset to any community, which can gain a massive source of income from them; in fact, beach tourism is ever more frequently the essential target of countries, aimed at attracting foreign investment or exchange. In this frame, prediction of coastal evolution at large scales is very important for coastal management and first conceptual design. Management strategies, almost at the early stages of the projects, may likely involve numerical simulations, but they can be extremely laborious, computing demanding and intensely time-consuming especially when involving either wider coastal domain or longer time scales that basically encompasses the majority of coastal projects by now. Analytical solutions of the Diffusion Shoreline Equation (DSE) can be a valid alternative. I n these frames, given the surprisingly good predictive capabilities, they can isolate essential features of the processes, making them more readily comprehended, and can avoid cumulative errors associated with the accuracy of computational time-stepping models. Nevertheless, the rather complex mathematical form makes their use extremely challenging and confines them in the realm of high mathematic s. Ciccaglione et al. (2023) provided analytical solutions of the DSE for finite beaches bounded by outcrops of whatever length (bypassing or non-bypassing groin compartments). Differently from the other studies, the authors checked the applicability range of the solutions through the comparison with reliable numerical models; furthermore, using curve fitting analysis simple design tools were suggested to aid engineers in the practical applications. In this paper, a deep focus is given on the case of a bypassing groin compartment, and easy-to-use formulae are given to assess the lifetime of beach fill projects. A simple semi-theoretical solution is also given for the case of a compartment bounded by a very short groin, by introducing a "convective term" modelled via a Heavy-side function, H (x). The practical usefulness of this solution is proved through an application to the evolution of a real beach along Italy's Adriatic coast. • Long-term shoreline evolution is important for coastal management and planning. • Analytical solutions are valid tools for estimating shoreline change in a bypassed cell. • Simple formulae are derived for the response of a beach fill into bypassing cells. • The applicability range is limited by the shortness of the bypass groin. • "convective" correction is checked against a coastal segment of the Adriatic coast. [ABSTRACT FROM AUTHOR]

Abstract: Sediments of the Marano and Grado Lagoon (Adriatic Sea, Italy) represent one of the world’s most major repositories of mercury (Hg). Its presence is a direct consequence of the historical mining activity in nearby Idrjia (Slovenia), as well as significant discharges from a chlor-alkali plant into the Aussa–Corno river system, which connects to the lagoon. Previous studies have shown that sediment acts as secondary source of Hg species to the overlying water column in natural conditions. However, evidence for the effects of resuspension on the dynamics of Hg species is still lacking. The work reported in this paper formed part of the multidisciplinary “MIRACLE” project, aimed at identifying areas at low risk of Hg bioaccumulation in commercial Manila Clams, an important part of the local economy in this region. The effect of resuspension on the cycling of inorganic mercury (IHg), reactive mercury (RHg) and methylmercury (MeHg) between the sediment and water column was investigated in a mesocosm study. Two experiments were conducted in October 2009 and September 2010 based on material collected from sites heavily impacted by Hg and periodically subjected to dredging activities. Designed to mimic the resuspension of particles, both experiments revealed that the release of Hg species from the solid to the dissolved phase became negligible quickly after the event. MeHg values did not change according to total mercury (THg), suggesting that the enhancement of methylation processes may occur. The findings reported in this paper may be useful for the local management of dredging and fishing activities, although mass balance calculations showed that the total flux of Hg species are trivial compared to lagoon-wide processes. [Copyright &y& Elsevier]

Abstract: This paper reports a study of the field measurements and monitoring of wastewater discharge in sea water at Bari East (Italy). A wastewater sea outfall system is an integral and fundamental part of each wastewater treatment with ultimate sink in the sea water. The design of a water treatment plant and wastewater outfall must take into account the use of the environmental water, the values of physicochemical parameters to be respected in order to safeguard the use itself and the quality of the environmental water where wastewater is issued. In the present study measurements of sea current velocity components were carried out with a VM-ADP (Vessel-Mounted Acoustic Doppler Profiler). Salinity, wind directions and velocities were assessed with, for one survey, the total faecal coliforms and other biochemical parameters. It was emphasized that the measurements necessary for monitoring cannot be concentrated in the wastewater outfall pipe zone only, but should be extended to a neighbouring area of the outfall pipe, with an extension depending on the wastewater discharge, the polluting charge and the magnitude of the sea currents and the winds typical of the zone of interest. The analyses presented in this paper confirm that the sea zones close to the wastewater outfall pipe are particularly sensitive and vulnerable. Such results must be considered in the planning of a wastewater outfall pipe. [Copyright &y& Elsevier]

This paper presents the results of an environmental geochemical investigation of the Gulfs of Naples and Salerno, near the Campania plain (Southern Italy). Surface marine sediment samples were collected during three field campaigns: 96 from the Gulfs of Naples and Salerno (NaSa); 123 from the Bagnoli site coastal area (BaSi); and 11 from the ports around the Gulf of Naples (PoNa). Elemental concentrations were determined and their interpolated distribution maps were compiled. Three geochemical sources (or processes) were determined associating elemental distribution with the results obtained from a R-mode factor analysis: 1) geogenic, 2) water kinetics and 3) anthropogenic. The results are presented as raw data single element distributions of eight potential toxic elements (PTEs) (As, Cd, Cr, Cu, Hg, Pb, Ni and Zn) in the forms of raw data and additive log-ratio transformed data. The latter showed advantages in revealing the actual distribution patterns. Geochemical background reference values of PTEs were determined from the median value of local background reference values. Based on these values, pollution impact analysis was carried out to both BaSi and PoNa samples, indicating most of BaSi and PoNa sediments were affected by moderate to strong Pb, Zn, Cd and Hg pollution. An ecological risk assessment was subsequently carried out on the entire database, pointing a toxic risk ranking in the order Pb > As > Ni > Cd > Hg > Cr. [ABSTRACT FROM AUTHOR]

Abstract: The significance of geometry in natural embayments has been at the center of attention in only a few coastal studies and needs to be analyzed in detail. The present paper focuses on 1) the significance of planform geometry and orientation of embayed beaches and headlands relative to incident wave energy; 2) Depth of closure, whether located inside or outside bays; 3) cross-shore sediment size variation in embayments. Studies were performed in 23 pocket beaches of Elba Island (Italy). The results indicate that exposure to incident wave energy does not determine the orientation of pocket beaches. Regardless of the angle of wave incidence, there is a strong correlation between the orientation of pocket beaches and the alignment of headlands, indicating a static equilibrium. The location of Depth of closure in the embayments shows that bed activity is fully captured inside seven bays, while nine bays are partially closed and seven are completely open. Sediment size data, available for five embayments, suggest an offshore-coarsening trend starting where the depth increase is counteracted by higher exposure to waves. A conceptual model is proposed for this process. [Copyright &y& Elsevier]

Abstract: In this paper, we show how the integration of monitoring data and mathematical model can generate valuable information by using a few examples taken from a well studied but complex ecosystem, namely the Lagoon of Venice. We will focus on three key issues, which are of concern also for many other coastal ecosystems, namely: (1) Nitrogen and Phosphorus annual budgets; (2) estimation of Net Ecosystem Metabolism and early warnings for anoxic events; (3) assessment of ecosystem status. The results highlight the importance of framing monitoring activities within the “DPSIR” conceptual model, thus going far beyond the monitoring of major biogeochemical variables and including: (1) the estimation of the fluxes of the main constituents at the boundaries; (2) the use of appropriate mathematical models. These tools can provide quantitative links among Pressures and State/Impacts, thus enabling decision makers and stakeholders to evaluate the effects of alternative management scenarios. [Copyright &y& Elsevier]

Abstract: Seagrass meadows are ecosystems of great ecological and economical value and their monitoring is an important task within coastal environmental management. In this paper, an acoustic mapping technique is presented using a profiling sonar. The method has been applied to three different sites with meadows of Zostera marina, Zostera noltii and Posidonia oceanica respectively, with the aim to test the method’s applicability. From the backscatter data the seabed could be identified as the strongest scatterer along an acoustic beam. The presented algorithm was used to compute water depth, seagrass canopy height and seagrass coverage and to produce maps of the survey areas. Canopy height was estimated as the distance between the bed and the point where backscatter values decrease to water column values. The algorithm was extended from previous methods to account for a variety of meadow types. Seagrass coverage was defined as the percentage of beams in a sweep where the backscatter 5–10 cm above the bed was higher than a threshold value. This threshold value is dynamic and depends on the average backscatter value throughout the water column. The method is therefore applicable in a range of turbidity conditions. Comparison with results from other survey techniques (i.e. dive surveys, underwater videos) yielded a high correlation which indicates that the method is suited to measure seagrass coverage and height. Analysis of the data showed that each seagrass species has a characteristic canopy height and spatial coverage distribution. These differences were used to undertake a preliminary species identification, as each species has a typical canopy height and preferred depth range. Furthermore, the results show that these differences can be used to track boundaries between species remotely. Finally, the application of the meadow distribution pattern to the health of a meadow is discussed. [Copyright &y& Elsevier]

Grain-size analysis has long been used as a descriptor of transport and depositional processes. This paper presents the possibility of using image-based granulometries, not yet widely used in the earth sciences, to characterize granulometric composition of unconsolidated estuarine and marine sediments. To test the method, conventional sediment analysis of siliceous and calcareous sediments are compared to image-based analysis of sediments obtained along the O¨re estuary (Northern Sweden) and the Adriatic Sea (Croatia and Italy). These grains have different textural characteristics, composition, roundness and specific surface area. Granulometric parameters are calculated using both a graphical method and the mathematical method of moments. Grains have been imaged using a microscope and mathematical granulometries have been applied to the digital data. Image-based granulometric moment descriptors are compared with sieve + Coulter counter-derived moments. Although it is not claimed that digital-imaging should be the only method used in sedimentology, the results show the potential of applying digital electronic imaging to granulometric analysis of sediments. In this way, sampling for granulometric analysis and sieving processes combined with Coulter counter analysis of fraction <32 μm could be eliminated and a large area of sediment surface could be covered in a short time. [Copyright &y& Elsevier]

The paper shows the results of a geochemical - geophysical survey on the decommissioned industrial area of Bagnoli (Naples, southern Italy). Analyses of 15 priority congeners of Polycyclic Aromatic Hydrocarbons (PAHs) were carried out on 21 sediment cores, collected on the beaches surrounding the old iron and steel industrial plant that was active over the last century. Anomalous high concentrations of PAHs were detected in this area, up to 87,000 μg g−1 d.w. In particular, most congeners were embedded inside a mainly sandy layer, characterized by a dark colour and high resistivity values. The joined use of Electrical Resistivity Tomography, chemical data and direct observation of cores allowed a volumetric estimation of the polluted layer corresponding to 20,200 m3. A total of 24,100 m3 of less polluted materials cover the dark, highly polluted layer. In addition, the geophysical-environmental approach helped to disentangle the deep interactions between the beach area, coastal changes and fluid vents. The actual coastal morphology is the result of historical, anthropic-driven rapid evolution that we reconstructed by using available historical images. The achieved results underline a crucial role played by combining geophysical and geochemical methodologies for a deeper and systematic understanding of anthropogenic impacts in coastal systems affected by multiple and combined stressors. Image 1 • Huge anthropic modification were introduced in the coastline at the Bagnoli brownfield site, Naples, Italy, during the past Century. • The Bagnoli Coat is affected by high level of pollution, consisting in high concentrations (up to 87,000 μg g-1 d.w) of PAH and an oil liquid phase.Geophysical and chemical constrains were combined to reconstruct the historical evolution of environmental impact in this area. • Coastal changes have ruled the emplacement of polluted sediments. • A potential time and space reconstruction is proposed. [ABSTRACT FROM AUTHOR]

Storm surge and wave runup are key determinants of the potential for beach overwashing during storm events. However, the prediction and quantification of wave runup on embayed beaches is strongly influenced by particular characteristics (e.g., irregular morphology, low tides, absence of swell, etc.) which differ from those on open beaches, and have rarely been investigated in literature. In the present paper, a model framework aimed at predicting wave-induced runup on an embayed sandy beach is validated by means of measurements derived from a video-monitoring station, recently installed in South Italy, during two storm events in 2016. The numerical approach employs MeteOcean forecasted waves within SWAN and SWASH models (in both 2-d and 1-d mode). The combination of multibeam and d-RTK surveys with Unmanned Aerial Vehicle (UAV) imagery provides high resolution depth grid (0.015 m), particularly required in shallow waters, where wave hydrodynamics is highly influenced by the bottom. The results show and discuss the agreement between video measurements and 2-d predictions of runup. A sensitivity analysis of the Manningfls roughness factor is needed in 1-d simulations. The accuracy of the empirical formulas in predicting wave runup in an embayed beach is also investigated, showing mainly an overestimation of the observations. [ABSTRACT FROM AUTHOR]