Search results for "Mediterranean"
showing 10 items of 3196 documents
The author's reply to N.R. Haddaway.
2017
Abstract In this reply we respond to the commentary of Dr. Haddaway addressed in searching for pitfalls in our systematic mapping exercise “Collating science-based evidence to inform public opinion on the environmental effects of marine drilling platforms in the Mediterranean Sea” recently published in Journal of Environmental Management (Mangano, M.C. and Sara, G. 2017. Journal of Environmental Management 188: 195–202). We discussed each so called “pitfalls” and, in our opinion, the main cornerstones of systematic map – SM (repeatability, comprehensiveness, transparency, traceability, quality, generalizability) are safe guaranteeing the “gold standard” required by this technique. Where nee…
Effectiveness of Posidonia oceanica biotic indices for assessing the ecological status of coastal waters in the Saronikos Gulf (Aegean Sea, Eastern M…
2017
Biotic indices are considered key assessment tools in most national and European policies aimed at improving the quality of coastal waters. At present, several Water Framework Directive (WFD)-compliant biotic indices based on the marine angiosperm Posidonia oceanica have been developed and applied in the Mediterranean Sea. In this study, we investigated the effectiveness of four different P. oceanica indices (POMI, PREI, Valencian CS, and BiPo) in evaluating the ecological status of coastal waters in a case study area of Greece. The evaluation, comparison, and validation of the Ecological Status Class (ESC) assessments obtained by each index were based on a set of eight common sites that en…
Distribution of sea urchins living near shallow water CO2 vents is dependent upon species acid-base and ion-regulatory abilities.
2013
To reduce the negative effect of climate change on Biodiversity, the use of geological CO2 sequestration has been proposed; however leakage from underwater storages may represent a risk to marine life. As extracellular homeostasis is important in determining species' ability to cope with elevated CO2, we investigated the acid-base and ion regulatory responses, as well as the density, of sea urchins living around CO2 vents at Vulcano, Italy. We conducted in situ transplantation and field-based laboratory exposures to different pCO2/pH regimes. Our results confirm that sea urchins have some ability to regulate their extracellular fluid under elevated pCO2. Furthermore, we show that even in cl…
Seasonal variability of diet and trophic level of the gelatinous predator Pelagia noctiluca (Scyphozoa)
2018
13 pages, 5 figures, 2 tables, supplementary information https://doi.org/10.1038/s41598-018-30474-x
Long-term effects of elevated CO2 on the population dynamics of the seagrass Cymodocea nodosa: Evidence from volcanic seeps
2021
Population reconstruction techniques was used to assess for the first time the population dynamics of a seagrass, Cymodocea nodosa, exposed to long-term elevated CO2 near three volcanic seeps and compared them with reference sites away from the seeps. Under high CO2, the density of shoots and of individuals (apical shoots), and the vertical and horizontal elongation and production rates, were higher than at the reference sites. Nitrogen limitation effects on rhizome elongation and production rates and on biomass were more evident than CO2 as these were highest at the location where the limitation of nitrogen was highest. At the seep where the availability of CO2 was highest and nitrogen low…
Micropredation on sea urchins as a potential stabilizing process for rocky reefs
2012
Rocky reefs can shift from forest, a state dominated by erect algae with high biodiversity, to barren, an impoverished state dominated by encrusting algae. Sea urchins, abundant in barrens, are usually held responsible for the maintenance of this state. Predation by large fish can revert the barren state to forest by controlling sea urchin populations. However, the persistence of a community state sometimes seems to be independent from the presence of such large predators, suggesting the existence of other, unknown mechanisms ensuring their stability. Theoretical studies suggest that the settler stage of sea urchins is determinant for maintaining a given rocky reef state. In this study, we …
Preferential assimilation of seagrass detritus by two coexisting Mediterranean sea cucumbers: Holothuria polii and Holothuria tubulosa
2019
Abstract Holothuria polii and Holothuria tubulosa are two of the most commercially exploited sea cucumbers of the Mediterranean Sea. As deposit-feeders, they represent an important component of the benthic community. Hence, knowledge of their feeding behaviour is crucial for understanding their function in terms of benthic ecology and sediment dynamics. Using information obtained from stable isotope analysis, the food selectivity/assimilation, temporal variations in diet and trophic niche of H. polii and H. tubulosa were investigated. Analysis of carbon and nitrogen isotopic ratios in body wall tissue showed a preferential assimilation of seagrass detritus among multiple food sources, with …
Assessing the importance of nursery areas of European hake (Merluccius merluccius) using a body condition index
2017
Abstract In this study, we analysed the variability of reserve storage in juvenile European hake (Merluccius merluccius) off the western coasts of Italy (Central Mediterranean Sea). Reserve storage was measured by the hepatosomatic index (HSI), in relation to environmental and population covariates. HSI has been proved to be a consistent measure of energy storage in gadoids, thus reflecting quantity and quality of food availability for growth. Generalized Additive Models for Location, Scale and Shape (GAMLSS) were used to model the effect of depth, bottom temperature, bottom currents, fish density and fish body size on HSI of juvenile European hake. The results revealed that reserve storage…
Climate change exacerbates interspecific interactions in sympatric coastal fishes
2012
Summary 1. Biological responses to warming are presently based on the assumption that species will remain within their bioclimatic envelope as environmental conditions change. As a result, changes in the relative abundance of several marine species have been documented over the last decades. This suggests that warming may drive novel interspecific interactions to occur (i.e. invasive vs. native species) or may intensify the strength of pre-existing ones (i.e. warm vs. cold adapted). For mobile species, habitat relocation is a viable solution to track tolerable conditions and reduce competitive costs, resulting in ‘winner’ species dominating the best quality habitat at the expense of ‘loser’…
Social equity and marine protected areas: Perceptions of small-scale fishermen in the Mediterranean Sea
2020
Abstract Global conservation policy requires the scaling up of effectively and equitably managed networks of marine protected areas (MPAs). While progress has been made on spatial coverage, the fundamental aspects of effectiveness and equity are falling short. Past research has focused on management effectiveness in MPAs, but less attention has been given to social equity though it is an ethical imperative and instrumental to conservation. This study assessed the perceptions of SSF regarding recognitional, procedural and distributional dimensions of social equity using quantitative surveys in 11 MPAs across 6 countries on the Mediterranean Sea. To do so, we developed individual indicators f…