Search results for " Marine"

La gestione delle aree marine protette, tra obiettivi, scopi e considerazioni metagiuridiche

2012

Subtropical streams harbour higher genus richness and lower abundance of insects compared to boreal streams, but scale matters

2018

Aim: Biological diversity typically varies between climatically different regions, and regions closer to the equator often support higher numbers of taxa than those closer to the poles. However, these trends have been assessed for a few organism groups, and the existing studies have rarely been based on extensive identical surveys in different climatic regions. Location: We conducted standardized surveys of wadeable streams in a boreal (western Finland) and a subtropical (south-eastern Brazil) region, sampling insects identically from 100 streams in each region and measuring the same environmental variables in both regions. Taxon: Aquatic insects. Methods: Comparisons were made at the scale…

Improving the Downwind Sail Design Process by Means of a Novel FSI Approach

2021

The process of designing a sail can be a challenging task because of the difficulties in predicting the real aerodynamic performance. This is especially true in the case of downwind sails, where the evaluation of the real shapes and aerodynamic forces can be very complex because of turbulent and detached flows and the high-deformable behavior of structures. Of course, numerical methods are very useful and reliable tools to investigate sail performances, and their use, also as a result of the exponential growth of computational resources at a very low cost, is spreading more and more, even in not highly competitive fields. This paper presents a new methodology to support sail designers in ev…

Dati preliminari sulla variabilità spazio-temporale di Paracentrotus lividus nell’ AMP “Capo Gallo Isola delle Femmine”

2009

First Evidence of Contourite Drifts in the North-Western Sicilian Active Continental Margin (Southern Tyrrhenian Sea)

2021

We present the results of an integrated geomorphological and seismo-stratigraphic study based on high resolution marine data acquired in the north-western Sicilian continental margin. We document for the first time five contourite drifts (marked as EM1a, EM2b, EM2, EM3a, and EM3b), located in the continental slope at depths between ca. 400 and 1500 m. EM1a,b have been interpreted as elongated mounded drifts. EM1a,b are ca. 3 km long, 1.3 km wide, and have a maximum thickness of 36 m in their center that thins northwards, while EM1b is smaller with a thickness up to 24 m. They are internally characterized by mounded seismic packages dominated by continuous and parallel reflectors. EM2 is loc…

Effets du bruit marin sur le changement des poissons sparidés juvéniles entre les espèces et les stades de développement

2023

International audience; Marine noise is an emerging pollutant inducing a variety of negative impacts on many animal taxa, including fish. Fish population persistence and dynamics rely on the supply of early life stages, which are often very sensitive to disturbance. Impacts of marine noise pollution (MNP) on juvenile fish have rarely been investigated in temperate regions. This is particularly true for the Mediterranean Sea, which is considered as an MNP hotspot due to intensive maritime traffic. In this study, we investigate the relationship between MNP related to boat traffic and (i) assemblage structure and (ii) the density of juvenile fishes (post-settlers at different stages) belonging…

The adaptations to tube-dwelling life of Propsilocerus akamusi (Diptera: Chironomidae) larvae and its eutrophication-tolerant mechanisms

2019

Propsilocerus akamusi (Diptera: Chironomidae) is a dominant macroinvertebrate species in many eutrophic lakes in subtropical and temperate zones. P. akamusi larvae can migrate deep into the sediment (>30 cm) during summer where is no oxygen. However, to our knowledge, the specific adaptive tactics of its tube-dwelling life (>30 cm) and underlying mechanisms why this species is favored by nutrient-rich lakes remain limited. With the understanding above-mentioned issues, we can provide important information for the development of sensitive biomonitoring. We examined monthly morphological dynamics and physiological adaptations of P. akamusi to anoxic conditions, and environmental relationships…

Marine Invertebrates as Bioindicators of Heavy Metal Pollution

2015

The marine environment presents a range of anthropogenic contaminants. According to the World Health Organization, more than 100,000 chemicals are released into the global environment every year as a consequence of their production, use and disposal. The fate of a chemical substance depends on physical-chemical properties, in combination with the characteristics of the environment where it is released. Among the substances that accumulate in the sea, for anthropogenic activities, metals/metalloids have a leading position. Some of these have a biological role but their bioaccumulation is injurious. Chemical pollutants can cause effects on organisms, biodiversity and human health. Various eff…

Analysis of the effects of co-exposure to antibiotics and cadmium on sea urchin embryos

2014

In order to understand the mechanisms of responses to changes in the physical and chemical environment, as well as the mechanisms of developmental pathways, we investigated by RT-qPCR assays and light microscopy observations the impact of antibiotics and cadmium in P. lividus sea urchin embryos. In particular we inspected development and biomarkers for free radical damage and apoptosis. During development embryos were exposed to an antibiotic mix (Ab mix, usually added to sea urchin cultures) or to sulfamethoxazole/trimethoprim mix (TMP/SMX, usually added to aquacultures) and/or levels of 10-5, 10-4, 10-3 M CdCl2. Even though treatment with TMP/SMX apparently did not affect development, it …

Changement climatique et suivi de la biodiversité marine côtière aux Iles Kerguelen

2018

Nearshore marine habitats of the French sub-Antarctic islands concentrate a rich and unique biodiversity that is currently facing climate change and its still not well-understood and multifaceted effects. Understanding the impact of these changes and predicting the potential response of ecosystems requires advanced knowledge of marine life and the achievement of uninterrupted and long-term observing programs. The Proteker program, no. 1044 of the French Polar Institute Paul-Émile Victor, has been developped in partnership with the National Nature Reserve of French Southern Territories in order to establish an observatory of coastal marine biodiversity in the Kerguelen Islands and evaluate t…