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Seagrass meadows are important benthic habitats contributing to many aspects of ecological community health, beach stability and sediment supply. Relationships between morpho-sedimentary features and distribution of seagrass meadows were investigated through an integrated analysis of geomorphology, sediments and benthic habitat structure in a temperate nearshore setting (Esperance Bay, Western Australia). The results demonstrate that seagrass distribution is related to gradients in sediment texture and composition, hydrodynamics and human impact. Dense seagrass meadows occurred in more sheltered regions of the bay, whereas sparser vegetation was found in areas of higher wave energy and artificial activities (like ship anchoring and dredging activities). A preferential retention of heavier siliciclastic sediments was recorded in the seagrass meadows especially in areas with high sediment supply resulting in elevated beds and formation of intermates. Sediment characteristics suggest that carbonate sediment is transported onshore from the seagrass meadow supplying the beach system. The combined analyses of geomorphological features and sediment characteristics at Esperance have allowed identification of a prevalent eastward oriented sediment transport current. Seagrass beds are confirmed to be a sediment source in terms of sediment budget contributing to beach stability. Integrated geomorphological data, sediment analyses and benthic habitat mapping provide useful information for the management of coastal environments characterized by the presence of seagrass meadows by providing new insights on coastal processes.

This paper investigates the combined role of hydrodynamic forcing, sediment transport processes and sea bottom features in determining the location of the meadow upper limit of the endemic Mediterranean seagrass Posidonia oceanica. For this purpose, an approach including extreme wave analysis and numerical modelling is applied to two sandy beach systems located in southern Sardinia (Italy). Information about bathymetry, P. oceanica meadow extension and bottom features has been made available by previous published studies. Based on the 30-year long NOAA hindcast dataset, a wave climate analysis is carried out to identify the incoming storm wave conditions (1 year return period) to be simulated with the Delft3D model package. The simulation results extend the current knowledge highlighting the importance of wave-induced hydrodynamic parameters as limiting factors for the survival of P. oceanica meadows. In particular, the results suggest that on sandy substrata the meadow upper limit lies well offshore of the surf zone, in areas with little morphological activity, where the wave orbital velocities associated to storms are on the order of 0.8 m/s and the mean current magnitude does not exceed 0.5 m/s. On rocky bottoms, the P. oceanica meadow can extend up to the outer surf zone of storms and is thus able to colonize shallow areas subject to stronger hydrodynamic forcings than those observed on sand. This difference in the plant tolerance to wave forcing depending on the substratum type shows how both hydrodynamic and geological factors play a key role in defining the environmental conditions for the development of seagrass meadows.

This paper presents a map describing the main geomorphological and sedimentological features, hydrodynamics, benthic habitat distributions and human impact on the coastal and marine areas of the Archipelago of La Maddalena (NE Sardinia, western Mediterranean). This cartography is based on an interdisciplinary sea-land approach, with the aim being to support sustainable and successful beach management in the face of a changing climate and environment, thereby contributing to the achievement of the Agenda 2030 Sustainable Development Goals (13, 14 and 15). In the Main Map (1:14,000 scale), the static and dynamic features of the beach systems and adjacent inner shelf are divided into thematic sections that include the geomorphological elements, hydrodynamics, sedimentological distributions, benthic habitat (mainly Posidonia oceanica meadow) and anthropogenic impacts. The map establishes a fundamental, multidisciplinary benchmark that is able to provide substantial scientific support to policymakers in relation to future vulnerability-assessment activities and the definition of land-management strategies.

Urban Mediterranean beaches are often characterized by a fragile and unstable equilibrium that can be easily altered by ongoing climate change and by the increase in human pressure. This may pose serious threats to the survival of beach systems that cannot accommodate these modifications. In this paper, the spatio-temporal shift of the shoreline was investigated along two urban beaches in the Gulf of Cagliari (Poetto and Giorgino, southern Sardinia, western Mediterranean Sea) across a time frame of 62 years (1954&ndash, 2016). The Digital Shoreline Analysis System (DSAS) ArcGIS&trade, extension was used to extract different statistical parameters which allowed us to quantify the erosion and accretion rates. These data were further examined in relation to a number of anthropic and natural forcings in order to disentangle the factors controlling shoreline evolution. Eight sectors with interchanging net erosive and accretion trends were identified along the Poetto and Giorgino beaches. In six decades, some sectors of the two study sites appeared to have undergone great shoreline modification as a result of the intense anthropogenic activities impacting these coastal areas. The westernmost portions of both beaches were found to be the most vulnerable to erosion processes, such conditions were likely controlled by the interplaying of local hydrodynamics and by the intense coastal structures which affected these sectors. The highest retreat rates (mean end point rate (EPR) = &minus, 0.51/year) were recorded in the western limit of Giorgino beach. Along the western limit of Poetto beach, EPR erosion rates (mean EPR = &minus, 2.92/year) considerably increased in the years after the artificial beach nourishment carried out in 2002, suggesting that the majority of the nourished material was lost offshore or partly redistributed along the beach. Coastal structures, urban development, river catchment modification, industrial and port activities, beach cleaning and touristic and recreational activities have been identified as the ongoing causes of coastal alteration. If these factors remain constant, under projected climate change scenarios, these beaches are at risk of further increased flooding and erosion. In this context, the application of DSAS appeared as an essential tool, supporting a monitoring system able to provide understanding and, potentially, predictions of the short- to long-term evolution of these beach systems.

We produced a new suite of sea-level data which allowed assessing the Holocene evolution of the Bonifacio Strait, a key coastal sector of the Mediterranean Sea which experienced significant morphological changes since the Last Glacial Maximum. Squeezed between Corsica and Sardinia islands, this strait connects the two major basins of the western Mediterranean. Due to its peculiar geographic and morphological setting, the Bonifacio Strait is affected by extreme meteomarine conditions characterized by severe winds, waves, and currents. The millennial sea-level changes were reconstructed through multiproxy investigations made of sediment coring and underwater beachrock sampling carried out on both sides of the strait. These data provided fresh insights into the timing of the progressive opening of the Bonifacio Strait which followed the Last Glacial Maximum when Corsica and Sardinia were connected forming the largest Mediterranean island. Major palaeogeographic changes occurred before ~7 ka BP. Since that period, the significant decrease of the northern ice-sheet melting triggered a significant sea-level stabilization which induced only minor modifications in the palaeogeography of the strait. In the late Holocene, the isostatic-related subsidence became the dominant factor controlling the sea-level changes which rose with rates ≤0.35 mm a−1 in the last four millennia. Our data have also an important archaeological implication because they indicate that the Bonifacio Strait has not represented a significant geographical barrier along the early Neolithic migration path which connected mainland Italy to northern Corsica and finally to Sardinia. This further confirms the ability of early Neolithic communities to navigate not also across large sea stretches but also maritime areas characterized by extremely complex meteomarine conditions.

Using a comprehensive cartographic product, this paper aims to illustrate the evolution of the urban geomorphological setting of the urban coastal belt of Cagliari (southern Sardinia, Italy, western Mediterranean Sea). The geomorphological map (1:14,000) presented herein summarizes different data (e.g. urban development, anthropogenic features, geomorphological elements, recent deposits, sedimentological distribution, hydrodynamics and ecological components) acquired through an integrated sea-land approach and a multidisciplinary-multitemporal investigation. The main significant environmental changes are linked to urbanization, the development of port infrastructures (embankments along the shoreline and the construction of the canal harbour), remediation work and filling activities, and the hardening of dune and beach systems and cliffs. These man-made interventions have increased the vulnerability of the shore zones to flood hazards and risks, which are linked to sea-level rises and global warming.

De Muro, S.; Tecchiato, S.; Buosi, C.; Porta, M.; Bachis, M., and Ibba, A., 2018. Geomorphology, Sedimentology, Benthic Habitat as Tool For Supporting Coastal Management: Comparison Between Australian And Mediterranean Beach Systems. In: Shim, J.-S.; Chun, I., and Lim, H.S. (eds.), Proceedings from the International Coastal Symposium (ICS) 2018 (Busan, Republic of Korea). Journal of Coastal Research, Special Issue No. 85, pp. 1526–1530. Coconut Creek (Florida), ISSN 0749-0208.The characterization of a nearshore system using geomorphological, sedimentological and ecological data is regarded as baseline knowledge to effectively manage the coast and warrant coastal conservation. Particularly in areas where sediment nourishment is a regular practice, the differentiation between in-situ sediment production and artificial placement, revealed by detailed sediment analyses, is often an important task.In Esperance Bay (Western Australia) sediment nourishment and dumping are ongoing since the 1950s. The comparison with a Mediterranean site (Porto Pino, Sardinia, Italy) has improved the understanding of processes that regulate sediment distribution in the urbanized beach system of Esperance Bay. Porto Pino is a Mediterranean microtidal wave dominated embayment, characterized by environmental conditions similar to those of Esperance (i.e. climate, sediments, geology and benthic habitats), where sediment nourishment was not undertaken previously and the sediment facies can be considered as a natural analogue of the Esperance sediments. The results presented in this paper are useful for Esperance coastal managers as their provide further insights on the distribution of sediment derived from artificial placement.

Passarella, M.; De Muro, S.; Ruju, A., and Coco, G., 2018. An assessment of swash excursion predictors using field observations. In: Shim, J.-S.; Chun, I., and Lim, H.S. (eds.), Proceedings from the International Coastal Symposium (ICS) 2018 (Busan, Republic of Korea). Journal of Coastal Research, Special Issue No. 85, pp. 1036–1040. Coconut Creek (Florida), ISSN 0749-0208. Accurate predictions of swash excursion are fundamental for improving the understanding of swash zone dynamics and for coastal management and hazard applications. Researchers have provided several formulas for predicting the swash excursion on sandy beaches. However, the problem of the universality of these formulas is still open. In fact, it is not clear whether the existing formulations are applicable to a wide range of beaches and wave conditions. This study verifies 13 existing swash (total, incident and infragravity) formulations using 13 published experiments (636 swash measurements). The experiments were carried out on ...

In this study, we present a comprehensive map of a microtidal wave-dominated beach system based on an interdisciplinary sea–land approach and with the purpose of supporting a sustainable and successful beach management. The study area is located in a highly urbanized/industrialized coastal sector of the W side of Cagliari Gulf (S Sardinia, W Mediterranean). In the Main Map (1:15,000 scale), static and dynamic features of the beach system and adjacent inner shelf are divided into thematic sections, including geomorphological elements, bathymetry, sedimentological distribution, benthic habitat (mainly Posidonia oceanica meadow), hydrodynamics and anthropogenic features. The map constitutes an example of multidisciplinary benchmark to allow for long-term planning and management of this highly urbanized beach system. It is able to provide a substantial scientific support to policy-makers towards environmental restoration and sustainable development.

We use Genetic Programming (GP), a type of Machine Learning (ML) approach, to predict the total and infragravity swash excursion using previously published datasets that have been used extensively in swash prediction studies. Three previously published works with a range of new conditions are added to this dataset to extend the range of measured swash conditions. Using this newly compiled dataset we demonstrate that a ML approach can reduce the prediction errors compared to well-established parameterizations and therefore it contributes to the error in coastal hazards assessment (e.g. coastal inundation). Predictors obtained using GP can also be physically sound and replicate the functionality and dependencies of previous published formulas. Overall, we show that ML techniques are capable of both improving predictability (compared to classical regression approaches) and providing physical insight into coastal processes.

An integrated cartographic approach has been used to summarize different data (geomorphological, sedimentological, hydrodynamic, ecological and anthropic) from an urban microtidal, wave-dominated beach and adjacent inner shelf in a comprehensive and easily readable mapping output. The study area is located in S Sardinia (Italy, Mediterranean Sea) and focuses on Poetto beach. All the data in this study were processed to produce a Main Map (1:6400 scale) showing the key characteristics of the entire area and three detailed secondary maps (1:56,000 and 1:59,000 scale) that include topographic and eco-graphic profiles, the distribution of sedimentary facies and the main anthropic impact. This map, providing detailed information on the beach dynamics, human impact and the marine ecological status of the Poetto urban beach, represents a useful new tool to facilitate environmental conservation and beach management.

This article contains data about the values of the Dune Vulnerability Index (DVI) and the Partial Index Vulnerability (IVp) of eleven coastal dune systems located in Sardinia (Italy, western Mediterranean). Specifically, we present the values of 59 variables that summarize the condition of the studied dune systems, clustered in five groups: Geomorphological Condition (GCD), Marine Influence (MI), Aeolian Influence (AI), Vegetation Condition (VC), and Human Effects (HE). Data were collected during numerous field surveys and using aerial-photos. This dataset can be useful to evaluate the coastal dune vulnerability of several Sardinian beaches in order to drive local coastal managers towards an efficient management. Keywords: Coastal dunes, Coastal dune vulnerability index, Geomorphology, Beach management, Sardinia, Mediterranean sea

This paper presents an innovative multi-thematic map (1:2500) that integrates morpho-sedimentological data, hydrodynamic processes, seasonal morphodynamic transitions and the distribution of the benthic habitat of a Mediterranean microtidal, wave-dominated gravel beach system. It is part of a larger cartography of coastal areas, and is based on an interdisciplinary sea-land approach that is applicable worldwide and aims to facilitate coastal management practices and future scientific research. The applications to coastal management include: the facilitation of coastal vulnerability assessments; easy-to-access, up-to-date digital geospatial data; and baseline studies for the future assessment and monitoring of environmental changes. The main environmental features that control the marine processes of this gravel beach appear to be linked to geological and morphological contexts such as the presence of the river mouth, the outcropping of a beach-rock along the coastline, the deposition of gravelly sediment in the beachface and the seagrass cover.

In this paper, we present the results of a detailed geomorphological and sedimentological study of a coastal sector of southern Italy, the Pineta della foce del Garigliano SCI (i.e. Site of Community Importance), which is largely affected by shoreline retreat and the degradation of dune habitat. The analysis of shoreline evolution demonstrates that severe erosion processes have occurred over the last 50 years. They caused the complete dismantling of the foredune, whereas the anomalous and advanced position of the secondary dune promoted a progressive loss of vegetation habitat of high environmental value such as juniper (Juniperus oxycedrus ssp. macrocarpa). Morpho-sedimentary data and hydrodynamic models suggest that the main climate events promoted a net longshore transport toward the South. Our analyses confirm that erosion processes are linked to natural factors but several negative human practices have contributed to the acceleration of shoreline retreat and degradation of the dune habitat. In addition to its scientific value, the map and data here presented represent an important tool for beach management purposes.

The Great Australian Bight is a large carbonate cold water environment located on the central and western portions of the southern Australia. Seagrasses (Posidonia sp.) and macroalgae benthic habitats are widely distributed in the shallow water environment of southern Australia, contributing to the carbonate factory. This study investigated the distribution of modern benthic foraminiferal assemblages in the microtidal wave-dominated inner-shelf of Esperance Bay (southwestern Australia), that lies on the western margin of the Great Australian Bight. Benthic foraminifera were taxonomically identified and biotic parameters (species richness, density, Fisher-α index, Shannon–Weaver index, dominance) were calculated. Multivariate analyses (Hierarchical Cluster Analysis, Principal Component Analysis) were performed to understand foraminiferal distribution in the context of environmental conditions. Four main Foraminiferal assemblages have been recognized: (I) a nearshore assemblage of dense seagrass meadow, dominated by Lamellodiscorbis dimidiatus, Elphidium craticulatum, Elphidium crispum, Cibicidoides lobatulus, II) a second assemblage associated with unvegetated seabed (approximately 30 m depth) with Lamellodiscorbis dimidiatus, Elphidium crispum, Quinqueloculina disparilis, III) a third assemblage in the central sector of the bay, characterized by a discontinuous and mixed seagrass-algae coverage with Lamellodiscorbis dimidiatus, Elphidium crispum, Elphidium macellum, Cibicides refulgens, and Quinqueloculina poeyana, and IV) an epiphytic assemblage of transitional zone from the coastline to the upper limit of a mixed seagrass-algae meadow, dominated by Elphidium crispum, Chrysalidinella dimorpha, Planulinoides biconcava, Planoglabratella opercularis, Rugobolivinella elegans. The spatial distribution of the four assemblages appears closely related to sediment texture, seagrass cover and depth, but it is also influenced by the shoreface morphology and the hydrodynamic energy. The understanding of the ecological parameters that influence benthic foraminiferal distribution, composition and assemblage structure within seagrass meadows is useful for paleoecological and paleoenvironmental interpretations.

The results of this geomorphological study, which focuses on four Mediterranean embayed microtidal wave-dominated beach systems and the related inner shelf, are reported on a detailed geomorphological map (1:12,000 scale). The study area is located between Punta di Li Francesi and Lu Poltiddolu in NW Sardinia, W of the Strait of Bonifacio. The Main Map presents geomorphological, sedimentological, hydrodynamical and ecological (underwater vegetation) features indicated in nine sections of the map legend. Integrative maps (1:40,000 scale) of side-scan sonar surveys, sedimentary facies, survey routes and sampling point locations are also represented on the Main Map. This work summarizes 25 years of historical geomorphological datasets and can be considered as a reference for future comparisons of the study area as indicated by current European legislation. In addition to the scientific value of this study, the proposed map can be an important tool for coastal, beach and inner shelf management.

A high-resolution Chirp acoustic survey of 250 nautical miles performed in the La Maddalena Archipelago provided a scheme of the acoustic facies of the recentmost sediments and a frame of the large-scale bedforms linked to the last eustatic cycle that charac - terize its channels. Five main acoustic facies have been recognized and mapped. Due to the good coherence with the sediment texture map of the area, an interpretation of the acoustic facies in sedimentary terms is presented. The archipelago is characterized by a complex system of inlets, promontories, bays and channels ruled by the main tectonic trends of the region. A main, 20 km-long channel (Bucinara Channel) with numerous straits and some shoals divides the northern Sardinia coast from the main islands of Spargi, La Maddalena, Santo Stefano and Caprera. A shorter and larger channel occurs in the northern part of the Archipelago. Two minor sea branches connect these channels. The bathymetry of the area reveals that the channels generally have a flat bottom and steep flanks, with water depth mostly ranging between –35 and –60 m, with the exception of saddles and shoals. The sedimentary regime of the area is controlled by storm-induced currents and by a high carbonate production associated to the widespread presence of the Posidonia Oceanica seagrass, a marine Phanerogama that populates the flanks of the channels of the Archipelago. A multitude of morphologic forms can be attributed to the phases of falling, lowstanding, rising and high-standing of the last Pleistocene-Holocene eustatic cycle. Angular unconformities, gullies and sediment-incised palaeo channels along with abrasion platforms in the granitic basement witness the last sea level fall and low-stand. These forms now lie at water depths ranging between –33 m and –60 m and are covered by a thin veneer of sediments of the Holocene transgression. They have all been formed when the sea-level was about –110 m below the present datum and the Archipelago was a landscape of rocky hills separated by large, flat valleys scoured by torrent-like rivers. The Holocene rise of sea-level (Versilian transgression) caused the flooding of the landscape and the deposition of the thin sedimentary cover imaged by the acoustic profiles. The rising was punctuated by some sea-level still stands evidenced by terraced surfaces lying at depths between –33 m and –47 m which are coherent with the mapped and dated beach-rocks of the Bocche di Bonifacio strait. The decrease of sea level rise at 5000-6000 years B.P. and the following stabilization of sea level have triggered the present sedimentary and hydrodynamic conditions which, in turn, favoured the formation and maintenance of the bedforms. The Archipelago is dominated by an eastward directed sea current, and subordinately by a westward current. In the two main WNW-ESE and W-E trending channels of the Archipelago, the current flows have formed some longitudinal sand ridges up to 3 km long and 5 m high, while in the N-S oriented channels, transversal sand banks up to 10 m thick occur. Sea floor undulations, interpreted as sand waves, are present in some restricted areas close to the Sardinia coast in downflow position with respect to the headlands. Their wavelength (L) ranges between 10 to 40 m and the height (H) is up to 1,5 m, the ratio H/L

This article presents a morpho-sedimentological map of a Mediterranean embayed microtidal wave-dominated beach system and related inner shelf. The study area is located between Capo Boi and the Torre de su Fenugu sector, and focuses on Solanas beach in SE Sardinia. All of the collected data were processed to draw a main 1:7,000 scale map, which shows the general characteristics of the entire area, including its hydrodynamic, morphological, and sedimentological features (distribution of siliciclastic and biogenic/bioclastic sediments), rocky outcrops, beach rocks, and marine phanerogam meadow coverage (mainly Posidonia oceanica). Several secondary maps such as routes and paths, side-scan sonar photomosaic interpretations, and sedimentary facies have also been included. In addition to its scientific value, the map can be an important tool for beach management purposes.

The knowledge of the infralittoral ostracodes presents an increasing interest since it is an essential tool for several fields of research such as human impact of the coastal environments, including environmental monitoring, geoarchaeology and reconstruction of ancient shorelines. The study of the infralittoral ostracode fauna of a small bay of northern Sardinia may represent an useful piece of this knowledge. This bay near Porto Puddu is characterized by shallow seafloors presenting wide vegetated areas, progression of the shoreline and seasonal strem (southern sector). Moreover, its water column is conditioned by winds along the year (Astraldi et al., 1980).

Seagrass leaf litter is commonly found along shores all around the world. The Mediterranean Sea is not an exception, and along the sandy shore wide and thick deposits of leaf litter can be found. The deposition of these structures has not yet been studied, our aim is to clarify the depositional-erosive process of seagrass leaf litter on a Mediterranean beach. A video image system, consisting of a camera and a video camera, was used to investigate the dynamics of the deposition of seagrass litter on beaches. Time-exposure images proved useful in investigating the seagrass berm deposition over the monitored period by using the EOF analysis, while videos are used to describe every deposition and erosion cycle. The deposition of seagrass berms occurred from late October to early April, while during the rest of the year, the beach was free of litter. The first deposition occurred in October, when seagrass litter was available on the submerged bay domain, the seagrass berm erosion occurred after several peaks of wind speed, while the deposition started when the wind speed increases and the waves start to break near to the shoreline. The deposition of the leaf litter on the beach starts as a strandline at the landward edge of the wave action and proceeds seaward up to the shoreline. Litter residue, eroded away by the waves and floating in the inner surf zone can be redeposited in little patches at the end of an erosion cycle. In conclusion, leaf litter may be relevant to berm formation and litter floating in the inner surf zone and in the lower swash zone is part of the materials exchanged between submerged and emerged beach. © 2013 Elsevier Ltd.

The sedimentary features of the inner-middle shelf of the strait of Bonifacio (western Mediterranean) were analyzed to evaluate the relationship between the production and transport of biogenic carbonate sediments and the basin morphology and hydrodynamics. A three-dimensional hydrodynamic modeling was performed in order to simulate the influence of waves and currents at seabed level. Superficial sediments were collected at depths ranging from 5 to 80 m and were analyzed for grain size, mineralogical composition and skeletal carbonate composition. Posidonia oceanica seagrass meadows border the coasts in a narrow strip on both sides of the strait down to a depth of 40 m. At greater depths, the seabed is characterized by the presence of plateaus and ridges which are controlled by outcropping bedrock morphology. Waves and seabed currents are driven by the prevailing northwest and northeast winds. For both wind directions, higher values for the seabed current velocity, associated with wind-storm events, were detected in shallower sectors and along an east–west-oriented belt that connects the western Mediterranean and the Tyrrhenian Seas. The sediments range from sand to gravel and show a mixed biogenic carbonate/siliciclastic composition. This is due to the carbonate production associated with benthic ecosystems and the mixing of modern carbonate with relict sediments. Biogenic gravelly sands were found in association with Posidonia oceanica seagrass meadows and extended down to the circalittoral zone outside the deeper boundary of the meadows. This sedimentary facies was derived from the modern carbonate production associated with the P. oceanica ecosystem. Sediments collected outside the deeper limit of the meadows were identified as sediments deposited during the stand of the meadows at a deeper level during lower sea level conditions. Maerl (free-living calcareous red algae) beds are the main carbonate factory and are mainly located at the top of the rocky plateaus (at ∼50–55 m) formed by the outcropping of the bedrock. Downward, the increased currents at the seabed level in the east–west-oriented belt, which connects the western Mediterranean and the Tyrrhenian Seas, limit the extension of this carbonate factory. This results in a mixed sedimentary facies composed of biogenic carbonate and relict siliciclastic sandy gravel. Compared to other Mediterranean shelves, the strait of Bonifacio is characterized by a distinct oceanographic setting. This is due to the connection between two basins. The currents at the seabed play a crucial role in controlling the distribution of the carbonate factories.