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1.
Sensors (Basel) ; 24(14)2024 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-39065942

RESUMO

CORAL (Catamaran fOr UndeRwAter expLoration) is a compact, unmanned catamaran-type vehicle designed and developed to assist the scientific community in exploring marine areas such as inshore regions that are not easily accessible by traditional vessels. This vehicle can operate in different modalities: completely autonomous, semi-autonomous, or remotely assisted by the operator, thus accommodating various investigative scenarios. CORAL is characterized by compact dimensions, a very low draft and a total electric propulsion system. The vehicle is equipped with a single echo-sounder, a 450 kHz Side Scan Sonar, an Inertial Navigation System assisted by a GPS receiver and a pair of high-definition cameras for recording both above and below the water surface. Here, we present results from two investigations: the first conducted in the tourist harbour in Pozzuoli Gulf and the second in the Riomaggiore-Manarola marine area within the Cinque Terre territory (Italy). Both surveys yielded promising results regarding the potentiality of CORAL to collect fine-scale submarine elements such as anthropic objects, sedimentary features, and seagrass meadow spots. These capabilities characterize the CORAL system as a highly efficient investigation tool for depicting shallow bedforms, reconstructing coastal dynamics and erosion processes and monitoring the evolution of biological habitats.

2.
Sensors (Basel) ; 23(2)2023 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-36679731

RESUMO

It is well established that most of the plastic pollution found in the oceans is transported via rivers. Unfortunately, the main processes contributing to plastic and debris displacement through riparian systems is still poorly understood. The Marine Litter Drifter project from the Arno River aims at using modern consumer software and hardware technologies to track the movements of real anthropogenic marine debris (AMD) from rivers. The innovative "Marine Litter Trackers" (MLT) were utilized as they are reliable, robust, self-powered and they present almost no maintenance costs. Furthermore, they can be built not only by those trained in the field but also by those with no specific expertise, including high school students, simply by following the instructions. Five dispersion experiments were successfully conducted from April 2021 to December 2021, using different types of trackers in different seasons and weather conditions. The maximum distance tracked was 2845 km for a period of 94 days. The activity at sea was integrated by use of Lagrangian numerical models that also assisted in planning the deployments and the recovery of drifters. The observed tracking data in turn were used for calibration and validation, recursively improving their quality. The dynamics of marine litter (ML) dispersion in the Tyrrhenian Sea is also discussed, along with the potential for open-source approaches including the "citizen science" perspective for both improving big data collection and educating/awareness-raising on AMD issues.


Assuntos
Ciência do Cidadão , Resíduos , Humanos , Resíduos/análise , Monitoramento Ambiental , Poluição Ambiental , Plásticos
3.
Sensors (Basel) ; 22(18)2022 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-36146270

RESUMO

The rapid identification of beached marine micro-plastics is essential for the determination of the source of pollution and for planning the most effective strategies for remediation. In this paper, we present the results obtained by applying the laser-induced breakdown spectroscopy (LIBS) technique on a large sample of different kinds of plastics that can be found in a marine environment. The use of chemometric analytical tools allowed a rapid classification of the pellets with an accuracy greater than 80%. The LIBS spectrum and statistical tests proved their worth to quickly identify polymers, and in particular, to distinguish C-O from C-C backbone pellets, and PE from PP ones. In addition, the PCA analysis revealed a correlation between appearance (surface pellets roughness) and color (yellowing), as reported by other recent studies. The preliminary results on the analysis of metals accumulated on the surface of the pellets are also reported. The implication of these results is discussed in view of the possibility of frequent monitoring of the marine plastic pollution on the seacoast.


Assuntos
Microplásticos , Plásticos , Monitoramento Ambiental/métodos , Poluição Ambiental/análise , Lasers , Plásticos/química , Análise Espectral
4.
Polymers (Basel) ; 14(6)2022 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-35335441

RESUMO

In this paper, we present two novel experimental setups specifically designed to perform in situ long-term monitoring of the aging behaviour of commercial plastic granules (HDPE, PP, PLA and PBAT). The results of the first six months of a three year monitoring campaign are presented. The two experimental setups consist of: (i) special cages positioned close to the sea floor at a depth of about 10 m, and (ii) a box containing sand exposed to atmospheric agents to simulate the surface of a beach. Starting from March 2020, plastic granules were put into the cages and plunged in seawater and in a sandboxe. Chemical spectroscopic and thermal analyses (GPC, SEM, FTIR-ATR, DSC, TGA) were performed on the granules before and after exposure to natural elements for six months, in order to identify the physical-chemical modifications occurring in marine environmental conditions (both in seawater and in sandy coastal conditions). Changes in colour, surface morphology, chemical composition, thermal properties, molecular weight and polydispersity, showed the different influences of the environmental conditions. Photooxidative reaction pathways were prevalent in the sandbox. Abrasive phenomena acted specially in the sea environment. PLA and PBAT did not show significant degradation after six months, making the possible reduction of marine pollution due to this process negligible.

5.
Mar Pollut Bull ; 130: 140-152, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29866540

RESUMO

Our paper will show data on quantity, typology, distribution of beach litter (Anthropogenic Marine Debris - AMD) within a coastal macroarea surrounding the Pelagos Sanctuary, an International Protected Area in the NW Mediterranean Sea. AMD Monitoring and characterisation have been performed by using SEACleaner Protocol: an adapted version of UNEP/IOC, OSPAR and EU guidelines. 11 beaches located in 5 different areas, have been monitored with a total amount of thirty three surveys, from January 2014 to December 2015, during different seasons. Three kinds of beaches have been considered: Natural (belonging to MPAs), Urbanized and Urban. A total of 34,027 items on a total area of 32,154 m2 have been removed and classified. Spatial difference in abundance and composition of AMDs - as well as beach environmental quality - has been detected. Natural sites, and particularly protected areas close to river mouths show a major density compared to other areas.


Assuntos
Praias/estatística & dados numéricos , Resíduos/estatística & dados numéricos , Análise por Conglomerados , Monitoramento Ambiental , Itália , Mar Mediterrâneo , Plásticos , Análise de Componente Principal , Rios , Estações do Ano , Urbanização
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