A potential beach monitoring based on integrated methods

This study focuses on the analysis of sandy beaches by integrating sedimentological, geomorphological, and geophysical investigations. The beach represents an extremely variable environment where different natural processes act simultaneously with human activities, leading to the gathering of different methodologies of the Earth Sciences to study its evolution in space and time. The aim of this research is to propose a potential procedure for monitoring the morpho-sedimentary processes of sandy beaches by analyzing the textural and compositional characteristics of the sands and quantifying the volumes involved in the coastal dynamics. The study area includes two Apulian sandy beaches (Torre Guaceto and Le Dune beach) that are representative of the coastal dynamics of a large sector of the central/northern Mediterranean Sea involving the southern Adriatic Sea and the northern Ionian Sea. Sedimentological and ecological investigations allowed to describe the textural and compositional characteristics of the beach sands by interpreting their sand provenance and the physical/biological interactions within the beach. The topographic surveys carried out with a Terrestrial Laser Scanner and an Optical Total Station, aimed to quantify the variations of sediment volume over time, whereas the Delft3d software was applied to analyze the effects of the dominant wave motion on the sedimentary dynamics. Lastly, the geophysical techniques which included Sub Bottom Profiler procedures, Ground Penetrating Radar investigation, and resistivity models enabled us to calculate the sand sediment thickness above the bedrock

The textural and mineralogical features of Riva degli Angeli beach sands (Salento Peninsula, Southern Italy).

Riva degli Angeli beach (literally, Angel’s Shore) is an impressive portion of the coastal littorals characterizing the city of Porto Cesareo: one of the most wonderful landscapes and touristic attractions located in the Apulia Region Ionian side. It extends for 2.2 km between Punta Prosciutto and Punta Grossa headlands. From a naturalistic point of view, Riva degli Angeli covers a significant role, as it is part of the protected marine area (AMP) of Porto Cesareo. It is characterized by fifteen different habitats on the seabed, with a very high degree of representativeness of the Mediterranean submerged populations and a significant percentage of Posidonia Oceanica coverage. By a sedimentological point of view, it is a pocket beach (Milli et al., 2017) with no significant supply of sediment from adjacent sedimentary systems and therefore, the sands have an almost entire bioclastic origin. In 2016, a naturalistic engineering intervention was carried out in order to protect the dunes and to restore the coastline. While the intent to safeguard the entire beach environment from touristic activities and coastal erosion, a backshore nourishment procedure was conducted with uncertain provenance sands and unknown grain size. Indeed, the sands were compacted with Posidonia Oceanica layers forming a significant sand relief in the supratidal environments. After two years, the dune protections have been destroyed. The current beach profile contains few portions with a perfect flat top and a continuous erosional scarp (1.5m – 2.0m high) that causes the accumulation of Posidonia Oceanica at its base (Fig. 1). In this study, we show the results of some image analysis carried out on multitemporal orthophotos trying to recognize the beach evolution during the last 10 years. Two detailed sampling campaigns (2016 and 2018) were carried out in the backshore-foreshore-shoreface-offshore transition environments. Textural and mineralogical features of the sands have been analyzed in order to establish their variation within the beach and during the considered period

The textural features of sandy beaches along the Apulian coast.

The Apulia Region (Southern Italy) contains about 900 km of coastal sectors, which corresponds to 12% of the Italian littorals. Most of the economic and social activities are related to the coastal areas (fishing, transports, etc.) and the tourist facilities are concentrated in the coastal localities. Among all the different coastal types, sandy beaches are the most common (more than 650 km in length) since cliffs and rocky shores only give ¼ of the littoral sectors. Therefore, the coastal erosion is one the most potential threats for the economic development of the Apulia Region. In addition, the Apulian sandy beaches show a large variability, which is characterised by different sedimentological and ecological parameters of the Ionian and Adriatic coastal areas. This variability mainly depends on both variables coastal dynamics and terrigenous/bioclastic supply. In this study, we try to describe some present-day Apulian sandy beaches by using a limited set of quantitative parameters. To purpose this aim, three different sandy beaches from Apulia coast have been chosen: Torre Canne (Brindisi) and Alimini (Lecce) on the Adriatic coast and Porto Cesareo (Lecce) along the Ionian coast. Sampling procedures were carried out through diving techniques from foreshore to lower shoreface environments (local wave base is about 6 m). The grain-size analysis allowed us to calculate the statistical parameters of sands with unimodal distribution. The beaches characterised by erosive phenomena were represented by well sorted sands with high kurtosis and negative skewness values, whereas stable beaches were related to poorly sorted sands with lower kurtosis and positive skewness values. The relationship between the main statistical parameters (mean versus kurtosis, kurtosis versus sorting, kurtosis versus skewness and mean versus skewness) was used to establish the erosive or stable-prograding tendency of the beach. The most frequently occurring size class of the statistical distribution was analysed with a binocular optical microscope to evaluate the sands composition in quantitative terms. Therefore, the classification of sands included quarts, feldspar, carbonate grains and other components (pyroxene, amphibole and opaque minerals). Within the carbonates class, the percentage of bioclasts was also evaluated. The shell fragments quantity was variable among the different beaches and a bioclasts percentage variability could be defined at different water depths. The grain-size distribution and the mineralogical compositional of the beach sands are significant data to obtain the evolutionary beach tendency and to establish quantitative textural parameters that can be used for comparative procedures in nourishment interventions

Interaction between physical and biological process of a carbonate pocket beach - Le Dune (Ionian Sea, Southern Italy)

This study focuses on the analysis of a carbonate pocket beach located along a coastal sector of the Apulia Ionian-Sea (Le Dune beach). The beach develops for about 800 m and it is exposed to the south-westerly and southerly seas. Coastal sediments range from very coarse to medium-fine and they are mainly composed of bioclasts (more than 90%). The study area is part of a marine protected reserve characterised by 15 different habitats of the typical Mediterranean submerged populations and the presence of Posidonia Oceanica meadows.The absence of sediment-delivering rivers coupled with the significant anthropic pressure in the last decades, have led the Ionian littorals to be affected by erosional processes. Therefore, the aim of our research is to highlight the correlation between physical and biological processes by analysing the textural and compositional characteristics of beach sands, fundamental for pocket beach conservation.This research is part of a multidisciplinary project devoted to the analysis of beaches by integrating sedimentological, geomorphological and geophysical investigations to obtain reliable models for their evolution in space and time

Interaction between physical and biological process of a carbonate pocket beach – Le Dune (Ionian Sea, Southern Italy)

This study focuses on the analysis of a carbonate pocket beach located along a coastal sector of the Apulia Ionian-Sea (Le Dune beach). The beach develops for about 800 m and it is exposed to the south-westerly and southerly seas. Coastal sediments range from very coarse to medium-fine and they are mainly composed of bioclasts (more than 90%). The study area is part of a marine protected reserve characterised by 15 different habitats of the typical Mediterranean submerged populations and the presence of Posidonia Oceanica meadows. The absence of sediment-delivering rivers coupled with the significant anthropic pressure in the last decades, have led the Ionian littorals to be affected by erosional processes. Therefore, the aim of our research is to highlight the correlation between physical and biological processes by analysing the textural and compositional characteristics of beach sands, fundamental for pocket beach conservation. This research is part of a multidisciplinary project devoted to the analysis of beaches by integrating sedimentological, geomorphological and geophysical investigations to obtain reliable models for their evolution in space and time

Sediment provenance of a carbonate bioclastic pocket beach d Le Dune (Ionian Sea, South Italy)

This study focuses on the analysis of a carbonate bioclastic pocket beach located along a coastal sector of the Apulia Ionian Sea, Le Dune beach, South Italy. The beach develops for about 800 m and it is exposed to the south-westerly and southerly seas. Coastal sediments range from very coarse to mediumefine sands and they are mainly composed of bioclasts (more than 90%) which include molluscs, foraminifers, echinoderms, algae branched, bryozoans, spicules of sponges and arthropods. The study area is one part of a marine protected reserve characterised by 15 different habitats of the typical Mediterranean submerged populations and the presence of Posidonia oceanica meadows. The aim of our research is to highlight the correlation between physical and biological processes influencing Le Dune beach dynamics and its sediment provenance by analysing the textural and compositional characteristics of beach sands, which is fundamental for pocket beach conservation. The beach sand analysis, deriving from textural, compositional and bioclast investigations, underlines that one of the main indicators of the beach dynamics is the bioclast component, which provides relevant information about sand provenance and sediment transport. The beach constitutes a semi-close system only nourished by the shells of organisms and by the erosion of headlands and dunes without important sediment interchange with adjacent littoral sectors

A multidisciplinary study of sandy beaches along the Apulian coast (Southern Italy).

The Apulian coasts are leader in the seaside tourism sector, by offering a great variability of coastal landscapes with a widely acclaimed concentration of tourism on sandy beaches. The Apulia Region contains about 900 km of coastal sectors, which corresponds to 12% of the Italian littorals. During the last fifty years, a significant economic development of many maritime localities is seriously threaten by pervasive coastline retreats, which are one of the most current issues of the region. This study focuses on the processes influencing the mechanisms of erosion, transport and sedimentation in coastal areas characterized by sandy beaches in order to analyse the sedimentary dynamic with a multidisciplinary approach. To achieve this objective, two beaches have been chosen as representative examples of Ionian (Porto Cesareo, Lecce) and Adriatic (Torre Guaceto, Brindisi) sandy coastal sectors of the Apulia region. Both areas are part of Protected Marine Reserves with stunning emerged and submerged landscapes. In terms of sand compositional features, these beaches represent also end-members of the Apulian beaches: Porto Cesareo sands are mainly bioclastic, while Torre Guaceto sands have a predominant siliciclastic (lithoclastic) content. The application of a multidisciplinary approach consists of gathering and testing different techniques. Firstly, the use of the Terrestrial Laser Scanner (LST) will allow analysing the emerged beach environment in superficial and geomorphological terms by constructing three-dimensional terrain models and evaluating beach slopes. The thickness of the emerged beach will be quantified with georadar investigations, whereas a Multibeam procedure will determine different relief forms and the bathymetry of the sea floor. Lastly, the Sub Bottom Profiler technique will be applied to measure the thickness and the sediment volumes that are involved in the coastal dynamic. By a sedimentological point of view, the beaches have been monitored by measuring all possible physical data, using classical and modern techniques. Seasonal sedimentological sampling procedures were carried out through diving techniques from foreshore to lower shoreface environments (local wave base is about 6 m). The grain-size analysis allowed us to calculate the statistical parameters of sands with unimodal distribution. The variation of these parameters along the emerged and submerged subenvironments have been analysed across the entire beach profile. In addition, the relationship between the main statistical parameters (mean versus kurtosis, kurtosis versus sorting, kurtosis versus skewness and mean versus skewness) will be used to investigate the erosive or stable-prograding tendency of the beaches. The most frequent size class of the statistical distribution was investigated with a binocular optical microscope to evaluate the sands composition in quantitative terms. Therefore, the classification of sands included quarts, feldspar, carbonate grains and other components (pyroxene, amphibole and opaque minerals). Within the carbonates class, the percentage of bioclasts was also evaluated. In the end, the sedimentological study of current beach sands with those relicts of platform will allow their reliable use in sandy coast nourishments for future technical interventions

Analisi e monitoraggio della dinamica morfo-sedimentaria della spiaggia Le Dune – Porto Cesareo (LE).

Il presente studio riguarda i meccanismi di erosione, trasporto e sedimentazione nei settori costieri della Puglia. Lo scopo della ricerca è testare delle procedure di analisi, monitoraggio e salvaguardia di un tratto di litorale sabbioso, investigando i processi di modificazione morfo-sedimentaria della spiaggia, analizzando i caratteri tessiturali e composizionali delle sabbie e quantificando i volumi coinvolti nella dinamica costiera. L’applicazione di un approccio multidisciplinare permetterà, in un triennio, di analizzare e monitorare la spiaggia Le Dune, una pocket beach situata tra l’Isola della Malva e la cittadina di Porto Cesareo (LE). Il campionamento sedimentologico e le indagini ecologiche permetteranno di interpretare le interazioni fisico / biologiche della spiaggia. Indagini LST e georadar saranno adottate per lo studio del settore emerso. L’attuazione di profili batimetrici e del Sub Bottom Profiler consentiranno l’investigazione della spiaggia sommersa

Sedimentological features of asbestos cement fragments in coastal environments (Taranto, Southern Italy)

Asbestos cement materials (ACMs) are widespread in coastal environments as result of illegal dumping activities. This study focuses on the Taranto area (Italy) in the Mar Grande basin within the northern sector of the Ionian Sea. The complex history of dumping building materials containing high amounts of ACM into the coastal zone, and the erosion, transport and deposition in Marechiaro Bay is a serious environmental hazard. An interdisciplinary research methodology defines the temporal dumping succession, and the erosional processes and phases, the diffusion of ACM, the mineralogical characteristics, and existing physical status of the ACM. A multiscale investigation was conducted. Results show that from 1992 to 2000 a significant increment of dumping operations have occurred. The current cliff has been subject to erosion and redeposition phases, developing a new beach composed of these polluted man-made sediments. The findings persuade the local authorities to close the beach requiring remediation interventions