Angelo Ibba

Interpretation of coastal sediment quality based on trace metal and PAH analysis, benthic foraminifera, and toxicity tests (Sardinia, Western Mediterranean)

An integrated approach for the assessment of coastal sediment quality was utilised in three areas of Sardinia (Western Mediterranean, Italy). Sediments were analysed for trace metals and polycyclic aromatic hydrocarbons (PAHs), while benthic foraminifera were used as bioindicators. Furthermore, the embryo-toxicity test was used to provide ecologically relevant information using rapid and cost-effective screening tools. The aim was to evaluate the usefulness of coupling different analytical tools. The results revealed the presence of polluted sediments in areas exposed to petrochemical industries, smelters or military settlements. However, while foraminifera have presented similar indications for chemical analysis of contamination levels in the different areas, the toxicity test exhibited a poor relationship with the contaminants measured individually. The results raise questions concerning the bioavailability of contaminants released by sediments in the water column. Overall, the toxicity rate was significant in many samples in comparison with other sites studied in other Mediterranean regions.

Heavy metal accumulation in surface sediments at the port of Cagliari (Sardinia, western Mediterranean): Environmental assessment using sequential extractions and benthic foraminifera

Superficial sediments were taken at the port of Cagliari (Sardinia, Italy), which includes the oil terminal of one of the largest oil refineries in the Mediterranean. Significant trace metal concentrations were found in the whole port area. Sequential extraction of metals from the different sediment fractions (BCR method) showed a higher risk of remobilisation for Cd, which is mostly bound to the exchangeable fraction. Foraminiferal density and richness of species were variable across the study area. The living assemblages were characterized by low diversity in samples collected close to the port areas. Ammonia tepida and bolivinids, which were positively correlated with concentrations of heavy metals and organic matter content, appeared to show tolerance to the environmental disturbance. The sampling sites characterized by the highest values of biotic indices were located far from the port areas and present an epiphytic and epifaunal biocoenosis.

Morpho-sedimentology of a Mediterranean microtidal embayed wave dominated beach system and related inner shelf with Posidonia oceanica meadows: the SE Sardinian coast

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.

Morphodynamics of a Mediterranean microtidal wave-dominated beach: forms, processes and insights for coastal management

ABSTRACT The aim of this study is to present a new morphodynamic map (1:10,000 scale) of a wave-dominated sector of a Mediterranean ria-type coast (NE Sardinia, Italy). The area has been studied since 1995 with respect to its geomorphological and sedimentological processes. Our map is produced using topographic-bathymetric, textural and compositional data collected during different surveys conducted from 1995 to 2014. The Main Map shows forms, processes and deposits of the coastal belt, as well as the main geological outcrops, structural elements and the areal distribution of seagrass, mainly Posidonia oceanica (L.) Delile and Caulerpa prolifera (Forsskaal) Lamouroux. The map is useful for beach management purposes. It is noteworthy that the role of P. oceanica in the littoral area is twofold: (1) acts as a barrier to siliciclastic material from the backshore; and (2) a producer of biogenic/bioclastic sediment. Based on side-scan sonar images, the P. oceanica meadow appears to be threatened by direct mechanical damage caused by boat anchoring and mooring activities. The human impact on dune habitats has also been recognized and is related to pedestrian and vehicular transit, boat storage and infrastructure for bathing.

Field Observations, Video Monitoring and Numerical Modeling at Poetto Beach, Italy

ABSTRACT Brambilla, W.; van Rooijen, A.; Simeone, S.; Ibba, a.; DeMuro, S., 2016. Field observations, coastal video monitoring and numerical modeling of coastal processes at Poetto Beach, Italy. In: Vila-Concejo, A.; Bruce, E.; Kennedy, D.M., and McCarroll, R.J. (eds.), Proceedings of the 14th International Coastal Symposium (Sydney, Australia). Journal of Coastal Research, Special Issue, No. 75, pp. 825–829. Coconut Creek (Florida), ISSN 0749-0208. This work presents an analysis of hydrodynamics and morphological evolution during one year at Poetto Beach (South Sardinia, Gulf of Cagliari - Italy). The results, in the form of a numerical model, Delft3D, were validated using data obtained from a very reproducible low-cost video monitoring system. Subsequently, the model was used to study local hydrodynamics (Delft3D) during wave events. Poetto Beach is a wave-dominated urban beach system characterized by an inner shelf with Posidonia oceanica meadows. Bathymetric and topographic surveys were carried out every three months in order to understand the beach morphology. Sediment grain samples were taken alongshore/cross-shore in correspondence with the main morphologies. The Delft3D model was used to simulate waves and hydrodynamics. The numerical simulation (Delft3D) showed good agreement with the field data and video image analyses for the distribution and direction of the rip and longshore currents. This approach, which can be easily replicated on other urban beaches, could provide beach managers with useful information on how to prevent and minimize the effects of storms and flooding.

A comparison of geomorphic settings, sediment facies and benthic habitats of two carbonate systems of Western Mediterranean Sea and South Western Australia: Implications for coastal management

ABSTRACT Tecchiato, S., Buosi C., Ibba, A., Ryan, D.A., and De Muro, S., 2016. A Comparison of Geomorphic Settings, Sediment Facies and Benthic Habitats of Two Carbonate Systems of Western Mediterranean Sea and South Western Australia: Implications for Coastal Management. In: Vila-Concejo, A.; Bruce, E.; Kennedy, D.M., and McCarroll, R.J. (eds.), Proceedings of the 14th International Coastal Symposium (Sydney, Australia). Journal of Coastal Research, Special Issue, No. 75, pp. 562–566. Coconut Creek (Florida), ISSN 0749-0208. A similarity exists between the coastal areas of South Western Australia and South Sardinia (Italy-Western Mediterranean Sea), as temperate water carbonate sedimentation dominates the inner shelf at these locations. The seagrass carbonate factory regulates the deposition of modern bioclasts, and the distribution of seagrass meadows and accumulation of bioclasts is controlled by similar processes at the study sites. These biogenic components are mixed to quartz-feldspar sands producing significantly comparable sediment facies, which have been previously documented for Esperance Bay (South Western Australia) and off Porto Pino beaches (Sardinia). Whilst the geological settings of these areas show similar outcropping lithologies, the clastic component of these mixed biogenic and quartz-feldpar sand facies is transported by different agents in the Australian and Sardinian site. In this paper, the similarity between sediment facies is highlighted and their comparison has produced new insights into the processes regulating sediment accumulation in two hydrodynamically different embayments. The characteristics of seagrass beds and their link to the beach system are also compared and set within the context of Mediterranean and South Australian bioregions. These outcomes are relevant for beach management, as European and Australian environmental regulations are compared herein.

Geomorphology of four wave-dominated microtidal Mediterranean beach systems with Posidonia oceanica meadow: a case study of the Northern Sardinia coast

ABSTRACT 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.

Bars/troughs dynamics and evolution trend of the La Cinta beach (San Teodoro OT) - NE Sardinia

This work describes the dynamics and evolution trend in La Cinta beach located in San Teodoro, it is 4 km long and composed of fine quartz rich sand, backed by well-developed dune ridge and San Teodoros lagoon. The study began a few days after the flood on the 24th of September 09, which caused the breach of 25 openings on dry-beach.Sedimentary and hydrodynamic characteristics were studied. Short-term variations have been periodically monitored since the flood and tested using topo-bathymetric digital models, derived from data acquired in 4 different fi eld surveys. Models of wave motion and hydrodynamics were created using Delft3D software. The results obtained from these models (wave ray direction, deep current distribution, structure and surfzone dynamics) allowed to visualize the response of beach to wind/waves stress, forced from NE, E, SE (wind intensity 18m/s, 10m/s). Data acquired demonstrate the hight resilence of this beach, with tendency to re-establishment of steady state with short relaxation times.

Geomorphology and sedimentology of Porto Pino, SW Sardinia, western Mediterranean

ABSTRACT This paper presents a detailed (1:4000) geomorphological, sedimentological and ecological map of a Mediterranean microtidal wave-dominated beach system and adjacent inner shelf. This map is an innovative cartographic product that integrates a range of processes of present and past timeframes. It is part of a larger cartography on the coastal geomorphology of Sardinia (Italy) aiming to facilitate coastal management practices and future scientific research. The study area is located in SW Sardinia (Italy), and focuses on Porto Pino beach, an important tourist destination of semi-pristine nature, facing environmental pressures common to many coastal Mediterranean settings. In this context, the main human impact on coastal dune habitats is described and a full environmental characterization of the beach system is presented.

Geomorphology map of the marine and transitional terraces and raised shorelines of the Península Juan Mazía, Tierra Del Fuego. Straits of Magellan – Chile

This manuscript presents a detailed map (1:50,000) of the geomorphology of the marine and transitional terraces and raised shorelines linked to Holocene-Pleistocene (?) glacio-eustatic variations in Península Juan Mazía situated on the Segunda Angostura in the western area of the Straits of Magellan. The Main Map, centered on approximately 52° 40’ and 52°60’, was compiled through geomorphological survey in the field integrated with interpretation of aerial photographs and remote-sensing imagery. The survey has allowed mapping of a regular sequence of terraces and raised shorelines represented mainly by marine, and partially by transitional terraced deposits, located in four orders at the respective elevations of 18÷25 m, 6÷11 m, 3÷5 m and 1÷2 m above mean sea level. The Main Map also provides other features such as landforms and deposits, due to littoral, running water, glacial and wind processes.