scholarly journals New Approaches for the Observation of Transient Phenomena in Critical Marine Environment

2021 ◽  
Vol 9 (6) ◽  
pp. 578
Author(s):  
Roberta Ferretti ◽  
Massimo Caccia ◽  
Massimo Coltorti ◽  
Roberta Ivaldi
Keyword(s):  
Mediterranean Sea ◽  
Marine Environment ◽  
Environmental Conditions ◽  
Marine Environments ◽  
Transient Phenomena ◽  
New Approaches ◽  
Marine Vehicles ◽  
New Methodologies ◽  
Biogeochemical Parameters ◽  
Very High

This paper focuses on the development of new approaches to observe transient phenomena in critical marine environments using autonomous marine vehicles (AMVs) for the acquisition of physical and biogeochemical parameters of water and seabed characterization. The connection with metrological principles, together with the adoption of observing methodologies adjustable according to the specific marine environment being studied, allows researchers to obtain results that are reliable, reproducible, and comparable with those obtained through the classic monitoring methodologies. Tests were executed in dramatically dynamic, sensitive, and fragile areas, where the study and application of new methodologies is required to observe phenomena strongly localized in space and requiring very high resolutions, in time. Moreover, the harsh environmental conditions may present risks not only for the quality and quantity of the acquired data but also for the instrumentation and the operators. This is the case, for instance, in polar marine environments in proximity of tidal glaciers and in the Mediterranean Sea in areas characterized by seabed degassing activities, where AMV-supported monitoring procedures can allow for the safe observation of not repeatable and not completely predictable events.

Transformation of PBDE mixtures during sediment transport and resuspension in marine environments (Gulf of Lion, NW Mediterranean Sea)

2012 ◽  
Vol 168 ◽  
pp. 87-95 ◽  
Author(s):  
Joan A. Salvadó ◽  
Joan O. Grimalt ◽  
Jordi F. López ◽  
Xavier Durrieu de Madron ◽  
Serge Heussner ◽  
...  
Keyword(s):  
Sediment Transport ◽  
Mediterranean Sea ◽  
Marine Environments ◽  
Gulf Of Lion ◽  
Nw Mediterranean ◽  
Nw Mediterranean Sea

scholarly journals Implementation and validation of a new operational wave forecasting system of the Mediterranean Monitoring and Forecasting Centre in the framework of the Copernicus Marine Environment Monitoring Service

2018 ◽  
Vol 18 (10) ◽  
pp. 2675-2695 ◽  
Author(s):  
Michalis Ravdas ◽  
Anna Zacharioudaki ◽  
Gerasimos Korres
Keyword(s):  
Mediterranean Sea ◽  
Marine Environment ◽  
Model Performance ◽  
Environment Monitoring ◽  
Marine Research ◽  
Forecasting System ◽  
The Mediterranean ◽  
Marine Environment Monitoring ◽  
Monitoring Service ◽  
Wave Forecasting

Abstract. Within the framework of the Copernicus Marine Environment Monitoring Service (CMEMS), an operational wave forecasting system for the Mediterranean Sea has been implemented by the Hellenic Centre for Marine Research (HCMR) and evaluated through a series of preoperational tests and subsequently for 1 full year of simulations (2014). The system is based on the WAM model and it has been developed as a nested sequence of two computational grids to ensure that occasional remote swell propagating from the North Atlantic correctly enters the Mediterranean Sea through the Strait of Gibraltar. The Mediterranean model has a grid spacing of 1∕24∘. It is driven with 6-hourly analysis and 5-day forecast 10 m ECMWF winds. It accounts for shoaling and refraction due to bathymetry and surface currents, which are provided in offline mode by CMEMS. Extensive statistics on the system performance have been calculated by comparing model results with in situ and satellite observations. Overall, the significant wave height is accurately simulated by the model while less accurate but reasonably good results are obtained for the mean wave period. In both cases, the model performs optimally at offshore wave buoy locations and well-exposed Mediterranean subregions. Within enclosed basins and near the coast, unresolved topography by the wind and wave models and fetch limitations cause the wave model performance to deteriorate. Model performance is better in winter when the wave conditions are well defined. On the whole, the new forecast system provides reliable forecasts. Future improvements include data assimilation and higher-resolution wind forcing.

Leisure Activities in Marine Environments

2020 ◽  
Author(s):  
Professor John Swarbrooke
Keyword(s):  
South Africa ◽  
Marine Environment ◽  
Leisure Activities ◽  
Risk Level ◽  
Marine Environments ◽  
Coastal Tourism ◽  
The Past ◽  
Made In

In recent years we have seen a veritable ‘explosion’ in the use of the sea for a growing variety of marine leisure activities. This is now a truly global phenomenon that can be seen from Iceland to South Africa, Australia to Florida. Activities in the sea have always been part of coastal tourism, from paddling and swimming to sailing and diving to angling and boat trips. However, in the past decade or two we have seen the invention of new activities and the developments of variations on traditional marine activities. We now have coasteering, wild swimming, paddle-boarding, RIB and banana boats and sea kayaking, all giving tourists further opportunities to get pleasure from the marine environment. Many of these activities also reflect a change in marine leisure with an increase in active rather than passive activities and an increase in adventure activities. This has, inevitably, increased the risk level of sea-based leisure activities in some ways. Several of the more adventurous new activities also involve travelling further from land or to less developed areas of coast, increasing the risk further. Interestingly, it appears that many tourists become ‘hooked’ on some sea-based leisure activities once they have experienced them on vacation. From that point onwards their desire to continue to participate in an activity will often influence their choice of vacation destination. The innovative developments we have seen in terms of sea-based leisure activities have led to a huge increase in participation in marine leisure activities. This has been stimulated by, and reflected in, the investment made in equipment and infrastructure for such activities by governments, commercial operators, and hotels and resorts.

scholarly journals Global variability in seawater Mg:Ca and Sr:Ca ratios in the modern ocean

2020 ◽  
Vol 117 (36) ◽  
pp. 22281-22292 ◽  
Author(s):  
Mario Lebrato ◽  
Dieter Garbe-Schönberg ◽  
Marius N. Müller ◽  
Sonia Blanco-Ameijeiras ◽  
Richard A. Feely ◽  
...  
Keyword(s):  
International Association ◽  
Open Ocean ◽  
Total Alkalinity ◽  
Polar Regions ◽  
Marine Environments ◽  
Physical Sciences ◽  
Seawater Chemistry ◽  
Sr:Ca Ratios ◽  
Biogeochemical Parameters ◽  
Dynamic Exchange

Seawater Mg:Ca and Sr:Ca ratios are biogeochemical parameters reflecting the Earth–ocean–atmosphere dynamic exchange of elements. The ratios’ dependence on the environment and organisms' biology facilitates their application in marine sciences. Here, we present a measured single-laboratory dataset, combined with previous data, to test the assumption of limited seawater Mg:Ca and Sr:Ca variability across marine environments globally. High variability was found in open-ocean upwelling and polar regions, shelves/neritic and river-influenced areas, where seawater Mg:Ca and Sr:Ca ratios range from ∼4.40 to 6.40 mmol:mol and ∼6.95 to 9.80 mmol:mol, respectively. Open-ocean seawater Mg:Ca is semiconservative (∼4.90 to 5.30 mol:mol), while Sr:Ca is more variable and nonconservative (∼7.70 to 8.80 mmol:mol); both ratios are nonconservative in coastal seas. Further, the Ca, Mg, and Sr elemental fluxes are connected to large total alkalinity deviations from International Association for the Physical Sciences of the Oceans (IAPSO) standard values. Because there is significant modern seawater Mg:Ca and Sr:Ca ratios variability across marine environments we cannot absolutely assume that fossil archives using taxa-specific proxies reflect true global seawater chemistry but rather taxa- and process-specific ecosystem variations, reflecting regional conditions. This variability could reconcile secular seawater Mg:Ca and Sr:Ca ratio reconstructions using different taxa and techniques by assuming an error of 1 to 1.50 mol:mol, and 1 to 1.90 mmol:mol, respectively. The modern ratios’ variability is similar to the reconstructed rise over 20 Ma (Neogene Period), nurturing the question of seminonconservative behavior of Ca, Mg, and Sr over modern Earth geological history with an overlooked environmental effect.

The seaweed resources of Israel in the Eastern Mediterranean Sea

2020 ◽  
Vol 63 (1) ◽  
pp. 85-95 ◽  
Author(s):  
Alvaro Israel ◽  
Alexander Golberg ◽  
Amir Neori
Keyword(s):  
Global Change ◽  
Mediterranean Sea ◽  
Eastern Mediterranean ◽  
Suez Canal ◽  
Cultural Tradition ◽  
Marine Environments ◽  
Seaweed Cultivation ◽  
Eastern Mediterranean Sea ◽  
Levant Basin ◽  
Marine Flora

AbstractIn spite of the natural harsh marine environments and continuous global change stressors affecting the Levant basin, the Israeli marine flora in the Eastern Mediterranean Sea is quite diverse, with about 300 recognized species. Such high seaweed biodiversity for a small maritime area is remarkable compared to the ca. 1200 species described for the entire Eastern Mediterranean Sea. Since about the year 1890, the Levant basin has been hosting over 115 seaweeds species that migrated from the Indo-Pacific through the Suez Canal. Indeed, approximately 16% of the marine flora is regarded as invasive or exotic to the Israeli shores, in a process that constantly reshapes seaweed populations and their biodiversity. In spite of significant contributions by Israeli scientists to the general biology and technologies for seaweed cultivation worldwide, Israel has little historical and cultural tradition of commercial seaweed cultivation, or use. At present, only two commercial companies are engaged in land-based seaweed cultivation (Ulva sp. and Gracilaria sp.) with a number of products marketed locally and abroad. Recently, offshore cultivation and biorefinery approaches have been explored, but not yet commercialized.

scholarly journals The culturable mycobiota associated with the Mediterranean sponges Aplysina cavernicola, Crambe crambe and Phorbas tenacior

2019 ◽  
Vol 366 (24) ◽  
Author(s):  
Elena Bovio ◽  
Estelle Sfecci ◽  
Anna Poli ◽  
Giorgio Gnavi ◽  
Valeria Prigione ◽  
...  
Keyword(s):  
Microbial Community ◽  
Mediterranean Sea ◽  
Marine Environment ◽  
Marine Fungi ◽  
Species Level ◽  
Fungal Communities ◽  
The Mediterranean ◽  
Satellite Analysis ◽  
First Time

ABSTRACT Marine fungi are part of the huge and understudied biodiversity hosted in the sea. To broaden the knowledge on fungi inhabiting the Mediterranean Sea and their role in sponge holobiont, three sponges namely Aplysina cavernicola, Crambe crambe and Phorbas tenacior were collected in Villefranche sur Mer, (France) at about 25 m depth. The fungal communities associated with the sponges were isolated using different techniques to increase the numbers of fungi isolated. All fungi were identified to species level giving rise to 19, 13 and 3 species for P. tenacior, A. cavernicola and C. crambe, respectively. Of note, 35.7% and 50.0% of the species detected were either reported for the first time in the marine environment or in association with sponges. The mini-satellite analysis confirmed the uniqueness of the mycobiota of each sponge, leading to think that the sponge, with its metabolome, may shape the microbial community.

Neoformation of halloysite on volcanic glass in a marine environment

Clay Minerals ◽  
1987 ◽  
Vol 22 (2) ◽  
pp. 179-185 ◽  
Author(s):  
T. Imbert ◽  
A. Desprairies
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Marine Environment ◽  
Experimental Studies ◽  
Volcanic Glass ◽  
Marine Environments ◽  
Thin Sections ◽  
Transmission Electron ◽  
Glass Shards

AbstractTransmission electron microscopy of ultramicrotomed thin-sections of Pleistocene and Eocene glass shards revealed the neoformation of (i) illite and (ii) halloysite at the glass periphery. According to previous experimental studies, halloysite neoformation in marine environments can occur on glass shards deposited in Si-rich sediments; an excess of Ca tends to inhibit the reaction.

Dim light vision of Squilla mantis L

1963 ◽  
Vol 205 (5) ◽  
pp. 927-940 ◽  
Author(s):  
H. Schiff
Keyword(s):  
Light Intensity ◽  
Mediterranean Sea ◽  
Environmental Conditions ◽  
Green Fluorescence ◽  
Fiber Analysis ◽  
Near Ultraviolet ◽  
Intensity Changes ◽  
Dim Light ◽  
Dim Light Vision ◽  
Shape And Size

The anatomy of the eye of Squilla mantis and the geometrical optics derived from it are briefly described. The shape and size of the electroretinogram (ERG) are dependent on a) position where it is picked up, b) the light intensity, and c) the change of intensity. Single-fiber analysis confirms the results obtained by the anatomy and the ERG of the eye. Frequency of response of a single secondary fiber to intensity changes of light is proportional to the derivate dI/dt ( I = intensity; t = time). The Squilla sees a moving object as the sum of the intensity changes caused by that object, varied in time and space. The eyes have a maximum of sensitivity for light of 535–555 mµ wavelength, and a second maximum in the near ultraviolet light, the latter partly seen as green fluorescence due to an eye pigment. Anatomy, physiology, and the environmental conditions have been combined to explain the vision of this animal, adapted to his life in the blue-violet twilight of the deeper Mediterranean sea.

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