Search results for " Mediterranean Se"
showing 10 items of 247 documents
Factors affecting fish assemblages associated with gas platforms in the Mediterranean Sea
2013
Abstract Understanding the role played by offshore platforms in marine ecosystems is acquiring increasing importance worldwide. In this work, underwater visual census techniques were applied to describe spatial and temporal patterns of fish assemblages associated with extractive platforms. Data were collected during three seasons according to the following spatial factors: Location (Adriatic and Ionian Seas), Depth (0–6 m and 12–18 m) and Distance from the platform (external and internal). Both univariate and multivariate analyses showed highly significant differences for each factor assessed in this study, as well as for the interaction among said factors. Results indicated that artificial…
Particulate Organic Matter Composition in A Semi-Enclosed Marine System
2001
Spatial and temporal changes in the biochemical composition of particulate organic matter in a semi-enclosed marine system (Stagnone di Marsala, Mediterranean Sea) were studied, on a monthly basis, from January to December 1994, in order to assess nutritional value of suspended particles for benthic suspension feeders. According to previous findings, the study site displayed a strong oligotrophy. Chlorophyll-a accounted for a very low fraction of the total suspended matter pool (0.1%), whereas at least 75% of POC was of detrital/heterotrophic origin. POC: PON ratio values indicate that bacterioplankton biomass accounted for a significant fraction of the total POC pool, displaying values com…
Seasonal changes in size, sex-ratio and body condition of the damselfishChromis chromisin the central Mediterranean Sea
2014
Chromis chromisis one of the most abundant fish species on the Mediterranean rocky shores. Acting as a by-pass of nutrients from the pelagic to the rocky littoral system, it plays an important role as a resource provider and has a relevant function in the community assemblage.Chromis chromishas many of the characteristics required of an indicator species (e.g. it is easy to recognize in the field, small sized, widespread and abundant). In this study we focused on individual size, sex-ratio and body condition in a damselfish population occurring in a central Mediterranean marine protected area. Fishing trials on a monthly basis (April–November) allowed us to assess seasonal changes in popula…
Unmanned aerial vehicle technology to assess the state of threatened biogenic formations: The vermetid reefs of mediterranean intertidal rocky coasts
2021
Abstract Vermetid bioconstructions are biogenic formations, built by sessile gastropod molluscs belonging to the family Vermetidae worldwide distributed, occurring in the intertidal and upper subtidal in the rocky shores. In the Mediterranean basin, they occur in complex and tridimensional structures that enhance the local biodiversity, allowing to qualify the structuring species as ecosystem engineers. Due to their ecological relevance and considerable extension along the coasts, we assessed their structural complexity using unmanned aerial vehicle (UAV) technology, as tool of littoral cartography analysis of these bioconstructions, and plaster hemispheres dissolution as a descriptor index…
Impact of Heavy Metals in Eggs and Tissues of C. caretta along the Sicilian Coast (Mediterranean Sea)
2022
In this study we compared the heavy metal concentration found in different tissues and eggs of the loggerhead sea turtle and evaluated the potential ecotoxicological risk for this important species. Eighteen heavy metal elements were determined in different tissues (liver, gonads, fat, kidney, heart, brain, and spleen) of nine individuals of Caretta caretta found stranded along the coasts of Messina (Sicily, Italy) and in the shell and yolk of six eggs from the island of Linosa (Sicily, Italy). For the analysis of the heavy metals, we used the analytical procedures in accordance with the EPA 200.8 method supplemented by EPA 6020b with three replicates for each measurement. The elements anal…
METODOLOGIE DI ANALISI DEL PAESAGGIO NELLA VALUTAZIONE DELL’ETEROGENEITÁ STRUTTURALE NEI REEF A VERMETI
2012
Landscape ecology is a discipline that uses many indices to describe environmental dynamics as a function of structural patch organization. Application of landscape ecology methods can be a way to evaluate heterogeneity and fragmentation of a habitat. Landscape indices were applied to evaluate if the algal heterogeneity of a vermetid reef can be related to the reef structure. Results show that heterogeneity is independent from reef width, but algal patches are wider and less abundant in a large cuvette and less wide but in higher number in small cuvette.
Searching for the competitive ability of the alien seagrass Halophila stipulacea with the autochthonous species Cymodocea nodosa
2023
The tropical seagrass Halophila stipulacea (Forsskål) Ascherson, 1867 entered in the Mediterranean Sea through the Suez Canal more than 100 years ago. In coastal-marine ecosystems the spatial niche of H. stipulacea is often overlapped with that of native Mediterranean Sea seagrasses and therefore it might out-compete them. Aiming to better understand its invasiveness potential, we monitored a Southern Mediterranean shallow coastal-marine water habitat from August 2010 to August 2011, where H. stipulacea co-occurred with the native seagrass Cymodocea nodosa (Ucria) Ascherson, 1870. Besides, the year-round dynamics of H. stipulacea was also monitored in four periods. To test the hypothesis th…
LA DIMENSIONE FRATTALE DEI REEF A VERMETI
2012
Fractal geometry can be an useful tool to describe the structural complexity of a vermetid reef. Using fractal analysis of small surfaces, the fractal dimension for the outer rim of some vermetid reefs can be established. A positive correlation between fractal values and the density of Dendropoma petraeum is evident.
DISTRIBUTION AND CONSERVATION NEEDS OF A NEGLECTED ECOSYSTEM: THE MEDITERRANEAN VERMETID REEF
2014
Vermetid reefs are a key intertidal habitat in the Mediterranean. Despite recent evidence of local extinction in the Eastern Mediterranean, their role as habitat engineers and the high numbers of ecosystem services they provide, vermetid reefs are among the least known marine habitats of the Mediterranean. Here we present a literature-based study to assess for the first time their distribution inside the basin and provide evidence of a general lack of protection at Mediterranean scale.