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The coastal domain of central western Sicily is characterized by the presence of rocky coasts, which mainly consist of pocket beaches situated between bedrock headlands that constitute ecological niches of great touristic and economic value. In this peculiar morphodynamic system, the sedimentary contributions are mainly derived from the rockfall that affects the back of nearby cliffs or the sediment supply of small streams that flow into it. In this study, we investigated the geomorphological processes and related landforms that contribute to the evolution of a pocket beach area located in a coastal sector of NW Sicily Island. The cliffs in this are affected by several rockfalls, and deposits from these rockfalls also add to the rate of sedimentary contribution. The analysis was conducted through the application of traditional approaches and contemporary methods that have previously been used to forecast the collection of input data in the field, often under difficult conditions due to the accessibility of the sites, and which have been supported by UAV surveys. Through the analysis of the digital models of terrain and orthophotos, geometrical and multitemporal analyses of landforms were carried out. A dedicated software was utilized for the detection of rockfall runout zones and block trajectories and for defining the automatic extraction of rock mass discontinuities. The data were compared with those derived from traditional geomechanical surveys. The availability of the existing and acquired remote sensing data proved essential for this study for both defining the reference geological model and for performing the site-specific analysis of rockfall. [ABSTRACT FROM AUTHOR]

Within an E.U.-funded project, BESS (Pocket Beach Management and Remote Surveillance System), the notion of a geographic information system is an indispensable tool for managing the dynamics of georeferenced data and information for any form of territorial planning. This notion was further explored with the creation of a WebGIS portal that will allow local and regional stakeholders/authorities obtain an easy remote access tool to monitor the status of pocket beaches (PB) in the Maltese Archipelago and Sicily. In this paper, we provide a methodological approach for the implementation of a WebGIS necessary for very detailed dynamic mapping and visualization of geospatial coastal data; the description of the dataset necessary for the monitoring of coastal areas, especially the PBs; and a demonstration of a case study for the PBs of Sicily and Malta by using the methodology and the dataset used during the BESS project. Detailed steps involved in the creation of the WebGIS are presented. These include data preparation, data storage, and data publication and transformation into geo-services. With the help of different Open Geospatial Consortium protocols, the WebGIS displays different layers of information for 134 PBs including orthophotos, sedimentological/geomorphological beach characteristics, shoreline evolution, geometric and morphological parameters, shallow water bathymetry, and photographs of pocket beaches. The WebGIS allows not only for identifying, evaluating, and directing potential solutions to present and arising issues, but also enables public access and involvement. It reflects a platform for future local and regional coastal zone monitoring and management, by promoting public/private involvement in addressing coastal issues and providing local public administrations with an improved technology to monitor coastal changes and help better plan suitable interventions. [ABSTRACT FROM AUTHOR]

Within an E.U.-funded project, BESS (Pocket Beach Management and Remote Surveillance System), the notion of a geographic information system is an indispensable tool for managing the dynamics of georeferenced data and information for any form of territorial planning. This notion was further explored with the creation of a WebGIS portal that will allow local and regional stakeholders/authorities obtain an easy remote access tool to monitor the status of pocket beaches (PB) in the Maltese Archipelago and Sicily. In this paper, we provide a methodological approach for the implementation of a WebGIS necessary for very detailed dynamic mapping and visualization of geospatial coastal data; the description of the dataset necessary for the monitoring of coastal areas, especially the PBs; and a demonstration of a case study for the PBs of Sicily and Malta by using the methodology and the dataset used during the BESS project. Detailed steps involved in the creation of the WebGIS are presented. These include data preparation, data storage, and data publication and transformation into geo-services. With the help of different Open Geospatial Consortium protocols, the WebGIS displays different layers of information for 134 PBs including orthophotos, sedimentological/geomorphological beach characteristics, shoreline evolution, geometric and morphological parameters, shallow water bathymetry, and photographs of pocket beaches. The WebGIS allows not only for identifying, evaluating, and directing potential solutions to present and arising issues, but also enables public access and involvement. It reflects a platform for future local and regional coastal zone monitoring and management, by promoting public/private involvement in addressing coastal issues and providing local public administrations with an improved technology to monitor coastal changes and help better plan suitable interventions.

Abstract Tourism has many environmental impacts and particularly in marine Protected Areas, which are declared to protect biological and environmental values. The long-term objective of Protected Areas can be complex considering that preservation of a site should not be in conflict with the right of user's access and with the quality of visitors experiences. Consequently, solutions may be found to find a balance between preservation and recreational uses that can be sustained by the environmental resources of the area. In this study we propose a methodology to help park manager to develop attractive sustainable tourism. The method is based on tourist perception assessment using website reviews and specifically TripAdvisor. We analyzed 637 reviews containing overall satisfaction, environmental aspects, transport means, service and management aspects. On the other hand, the calculation of carrying capacity, based on the Cifuentes method, provided insights about the interaction of human activities with the environment, considering biophysical characteristics, social factors and management policies. Our results suggest that the tourist carrying capacity is in its lower level and that tourist experience is judged excellent. Finally, the analysis of the TripAdvisor reviews may represent a useful instrument for decision makers by identifying negative aspects and solutions. Highlights • We analyse the tourism perception through the comments inserted in TripAdvisor. • We adopt a methodology to assess the carrying capacity in a marine Protected Area. • The study focuses on the sustainable use of two pocket beaches. • The method we proposed can be used by the decision-maker for planning processes. [ABSTRACT FROM AUTHOR]

Vieira da Silva, G.; Muler, M.; Prado, M.F.V.; Short, A.D.; Klein, A.H.F., and Toldo, E.E., Jr., 2016. Shoreline change analysis and insight into the sediment transport path along Santa Catarina Island north shore, Brazil. This paper presents a shoreline change analysis applied to identify the sediment transport path involving nine adjoining beaches, including dunes and spits, located along the microtidal eastern and northern shores of Santa Catarina Island (Brazil) and extending 50 km from Barra-Moçambique to Daniela. A data set was comprised of aerial images from 1957, 1978, 1998, 2002, 2007, and 2010, and the 2012 shoreline position measured with real-time kinematic GPS, topobathymetric data set, and a 60-year water-level time series. The images were rectified and the shoreline position for each year was extracted. The average errors (ranging from 1 to 9.8 m) of the rectification process as well as the horizontal tide-related errors (varying from 8.3 ± 2.6 m to 14.9 ± 0.6 m) were calculated within a confidence level of 95%. Two complementary approaches were used: (1) general trends analysis using linear regression rate method and (2) shoreline behaviour statistically analysed by Euclidean distance and year-to-year analysis. The results indicate an anticlockwise longshore transport between a series of beaches with variable orientation and separated by headlands, including a dune overpassing from Santinho delivering ∼10,000 m3 y−1 to Ingleses, and headland bypassing leading to the development of three spits along the protected part of the study area that have possibly been nourished by subaqueous sand transport from the updrift beaches. During its development the Ponta das Canas spit grew ∼7000 m3 y−1, controlling the sediment availability downdrift. As the spit grows it traps sediment and the downdrift area retreats; on the other hand, when the spit merges to the coast the sand spreads and the downdrift beaches prograde. [ABSTRACT FROM AUTHOR]

Rocky shorelines are commonly punctuated, with alternating high relief cliffs and incised embayments which host "pocket beaches". While multiple cases of ancient rocky shorelines associated with low relief ravinement surfaces have been documented in the geological record, deposits formed in pocket beaches and joint-cut coves are more rarely described. This poses the question "are high relief rocky coastlines and their associated deposits not preserved or have they been previously overlooked? Here we document exhumed examples of ancient granitic rocky shoreline systems of diverse morphologies from the Early Miocene of northern Austria, and compare them with modern systems in UK, Corsica, Spain and Norway. The preserved ancient examples offer a good opportunity to characterize these sedimentary systems, provide diagnostic criteria for their recognition and discuss the main controls on their occurrence and preservation in the rock record. From their stratigraphic and sedimentological analysis, and its comparison with modern examples, we interpret that these rocky shorelines form and get preserved during rapid rates of combined tectonic and eustatic sea-level rise, along lithological, structural and weathered "weakness" zones affected by normal low wave energy conditions interrupted by storms. These results provide a mechanism for predicting their potential occurrence and distribution during transgression of rocky coasts, with implications for exploration around structural highs and coastal management. • Miocene rocky shoreline deposits on top of granitic basement are described. • The deposits are interpreted to be formed in pocket beaches and joint-cut coves. • Deeply incised and shallow, scoop shaped, incisions are preserved. • The sedimentary infill is dominated by conglomerates and sandstones. • Their preservation potential and distribution can be predicted. [ABSTRACT FROM AUTHOR]

A new physical concept of relaxation time is introduced in this research as the time required for the beach to dissipate its initial perturbation. This concept is investigated using a simple beach-evolution model of shoreline rotation at pocket beaches, based on the assumption that the instantaneous change of the shoreline plan-view shape depends on the long-term equilibrium plan-view shape. The expression of relaxation time is developed function of the energy conditions and the physical characteristics of the beach; it increases at longer beaches having coarse sediments and experiencing low-energy conditions. The relaxation time, calculated by the developed model, is validated by the shoreline observations extracted from video images at two artificially embayed beaches of Barcelona (NW Mediterranean) suffering from perturbations of sand movement and a nourishment project. This finding is promising to estimate the shoreline response and useful to improve our understanding of the dynamic of pocket beaches and their stability. [ABSTRACT FROM AUTHOR]

We analyse the response of small embayed sandy beaches in marginal seas to various hydrometeorological drivers to isolate a specific mechanism that may stabilise beaches under bi-directional wind patterns. The focus is on the evolution of two sandy beaches (Pirita and Russalka) in Tallinn Bay, northeastern Baltic Sea, that are about 3 km apart and oriented at an angle of 35° with respect to each other. A large proportion of annual wave energy flux is packed into a very few days in the year. The wind direction, and thereby the direction of the wave fields, of the strongest storms in the year determines which coastal areas are most affected. We quantify the response of the beaches to hydrometeorological conditions over 12 years, 2008–2020 based on annual high-resolution measurements using airborne and terrestrial laser scanning technology. The fastest sediment removal from the subaerial beach occurs during time periods with elevated water level and strong wave energy flux. Even though annual variations in the sand volume of the subaerial beach are significant, both beaches are stable during the decade studied but respond differently. We outline specific mechanisms that maintain the beaches, best illustrated at Pirita beach where there is strong longshore sediment transport component driven by waves that often arrive the beach at a large angle. Sand that is removed from the higher subaerial segments of the northern part of Pirita beach and moved to the south by north-west storms during periods of elevated water levels, is deposited in the shallow nearshore (above about −0.5 m of the mean sea level). This sediment is then able to be transported back to the north during periods of lower water levels where even relatively small waves generated by moderate south-westerly winds can entrain and move the sediment. This mechanism, different from the classic cut and fill cycle, may implicitly stabilise beaches where there is a bi-directional wind regime and a small tidal range. Another, less explicit cross-shore mechanism, is found for the differently oriented Russalka beach where waves usually approach at a small angle with respect to the shore normal. This beach is maintained by a synchronisation of intense waves and water level that limits the depth of deposited sand with respect to mean sea level. The two mechanisms are thus fairly similar, however Pirita beach has extensive alongshore excursions of sand. • Laser scanning technique applied to quantify, in detail, the evolution of two beaches over 12 years. • The patterns of change generally do not match the course of hydrometeorological drivers. • The beaches are stabilised by specific mechanisms. • Sediment is moved in one direction under elevated water levels and back under low water levels. [ABSTRACT FROM AUTHOR]

A study of the geomorphology and vegetation in Palmeras Beach was conducted from a digital elevation model, systematic measurements of beach profiles for 15 months, analysis of equilibrium shape and measurements of vegetation, electric conductivity of the floodwater and granulometry at 15 parcels established along the beach. The beach can be divided into two sectors. The NE is characterized by a concave shape, beach cusps, steeper slope, higher elevation, wider dry zone, greater variability of the shape in plan and profile, greater tendency for accretion and herbaceous vegetation dominated by Rhynchospora polystachys. The SW sector has a convex shape, lower elevation, minimal dry zone width, lower variability of the plan and profile, its shape tends to erosion. The herbaceous vegetation is dominated by Sphagneticola trilobata and it has a higher proportion of dead palms. Although the length of the observations limits the conclusions on the seasonal and interannual variability of the beach, in the wet season there is loss of sand and the sea level rises. Also during El Niño years increased wave energy, which could be associated with coastal erosion was evident. In the long term, there is evidence of a change in wave direction and a tilting of the beach with accretion to the NE and erosion to the SW. [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: We investigated the variability of shoreline position of three adjacent pocket beaches at Barcelona city (NW Mediterranean) over a period of two years. Daily measurements of shoreline position were extracted from high-resolution video images and used to determine shoreline variability. Using empirical orthogonal function analysis we determine two dominant modes of shoreline variability. For all beaches analysed the mode that explains most of the variability (around 70%) describes the beach plan-form rotation which primarily occurs at the seasonal scale. The cross-shore translation of the beach profile, is described by the 2nd mode which explains around 30%. Both types of shoreline movement have been related to the previous nearshore conditions. This relationship was explored standardizing the translation/rotation of the shoreline and comparing it with time-averages of the cross-shore energy flux (EF csh) and the energy flux direction (EF D). Averages over 7 to 12days of EF csh were significantly correlated to the translation movement. Plan-form rotation was well described by 28 to 40day-averaging of EF D. Comparing results from the three beaches we determined that the time required to average the previous wave conditions depends on the beach characteristics (beach length and sediment grain size) in such a way that the greater the length of the beach and its sediment grain size, the slower its response. [Copyright &y& Elsevier]

Understanding time scales of beach response (erosion and recovery) to extreme storms is particularly relevant for management of coastal land and risk. Observations show that rock-bounded platform beaches are generally remarkably stable and only occasionally respond to extreme storm wave forcing with abrupt morphological changes. The present work aims to understand the conditions leading to the disruption of beach stability (storm thresholds for morphological changes) and to comprehend the conditions of the subsequent recovery. Results obtained at two rock-bounded beaches of the western Portuguese coast over five years provided the foundations of a new conceptual morphodynamic model. This model explains abrupt beach disruption as a consequence of full inundation of the beach profile during extreme storms, together with strong wave reflection at the rigid landward boundary, causing major erosion of the subaerial beach. We argue that the timescale of post-storm recovery depends essentially on the fate of the sediment transported offshore during the storm event. If sediments remain within the beach sediment cell (underwater beach section) beach recovery to pre-storm conditions is very fast, while recovery is much slower if sediments exit the beach sediment cell. In the latter case, beach recovery depends on external sand sources, which can lead to recovery time scales of several years. • We investigate conditions leading to abrupt morphological changes in rock-bounded platform beaches. • Total water level adequately describes thresholds for significant erosion during major storms. • A conceptual model explaining patterns of erosion and recovery is proposed. • Abrupt erosion is triggered by wave reflection at the landward hard boundary of the beach. • Beach recovery depends on the geological framework, which controls sediment exchanges with adjacent sediment cells. [ABSTRACT FROM AUTHOR]

Pocket beaches bounded by coastal structures are widely used as coastal systems that are in equilibrium for shoreline stabilization. Throughout the literature, several equations can be found to obtain the static equilibrium planform (SEP) of these embayed beaches, such as the parabolic bay shape equation (PBSE). The literature has already addressed some methodologies used to determine the location of the down-coast control point from which the parabolic shoreline is applicable for pocket beaches to the leeward side of a single headland structure. However, a methodology for locating this down-drift limit for double-curvature pocket beaches behind breakwater gaps is still lacking. This paper explores a methodology for locating this down-drift limit, hereafter called the intersection point (P i), and investigates the role of the breakwater gap configuration as well as the directional wave climate close to the gap by employing 32 prototype beach cases along the Spanish coast. Moreover, an extensive series of numerical simulations using a spectral wave model was carried out to model the wave refraction-diffraction conditions on the leeward side of a breakwater gap under different wave conditions and various gap configurations. The results show the importance of the gap width and its orientation (θ gap) with relation to the direction of the mean wave energy flux (θ EF) at the gap as well as the ratio of the widths of the two parts of the bay beach that are affected by the breakwaters, denoted as the breakwater influence ratio (BIR), on the location of the intersection point (P i). The results also indicated that a symmetrical pocket beach with a gap orientation (θ gap) parallel to the θ EF direction has an intersection point (P i) around the mid-width point of the breakwater gap. On the other hand, the larger the difference angle (Δ θ gap) between θ gap and θ EF is, resulting in asymmetrical beach cases, the wider the eccentricity of the location of the intersection point (P i) from the gap centerline towards the shallower landward breakwater of the gap is. New formulae were derived for calculating the angles used to locate the intersection point (P i) from the two diffraction points of the gap as a function of the gap width, BIR and the offshore distances of the diffraction points. The model showed good results, with R2 = 0.9571 and an RMSE value of 0.9731° in estimating the location of the intersection point (P i) in various prototype beach cases, confirming its utility for coastal engineering practices. Accordingly, a design procedure was proposed for the design of new equilibrium pocket beaches behind breakwater gaps. • Wave refraction-diffraction behind breakwater gaps is simulated with a spectral model. • The Best fit static equilibrium planform (SEP) is obtained for pocket beaches behind gaps. • Gap's configuration affects the SEP of double-curvature bay beaches. • The location of the intersection point (P i) point depends on the breakwater influence ratio. • Presence of eccentricity of (P i)'s location from the gap centerline for asymmetrical bays. [ABSTRACT FROM AUTHOR]

The distinctiveness of macrofaunal assemblages on different sandy beaches in the Maltese Islands was previously suggested by different single-season studies. A multi-seasonal sampling programme using pitfall trapping was implemented on four Maltese beaches to test the occurrence of this phenomenon. A total of 29,302 individuals belonging to 191 species were collected over a 2-year period, during which the beaches were sampled once per calendar season. A total of 77 species were recorded from single Maltese beaches only, of which nine were psammophiles. Non-metric multidimensional scaling analyses of pitfall trap species-abundance data resulted in a weak separation pattern, with samples grouping mainly in terms of beach and island rather than in terms of season or year of sampling, No physical variable could conclusively explain these patterns. It is concluded that although operating on Maltese beaches, macrofaunal assemblage distinctiveness is weaker than originally thought and can be attributed to the presence/absence or abundance of just a few psammophilic species. It is postulated that this phenomenon may be related to the ‘pocket beach’ nature of Maltese beaches, where headlands on either side of the beach to a large extent prevent the occurrence of longshore currents, resulting in semi-isolation of the populations of psammophilic species. A large number of single-beach records reported in this study highlight the high degree of beta diversity and spatial heterogeneity of Maltese beaches, and the conservation importance of the individual beach macrofaunal assemblages. [ABSTRACT FROM AUTHOR]