Search results for "terra"
showing 10 items of 4214 documents
Recreational and small-scale fisheries may pose a threat to vulnerable species in coastal and offshore waters of the western Mediterranean
2019
10 pages, 3 figures, supplementary material https://doi.org/10.1093/icesjms/fsz071
Biodiversity in canopy-forming algae: Structure and spatial variability of the Mediterranean Cystoseira assemblages
2018
Abstract In the Mediterranean Sea, Cystoseira species are the most important canopy-forming algae in shallow rocky bottoms, hosting high biodiverse sessile and mobile communities. A large-scale study has been carried out to investigate the structure of the Cystoseira-dominated assemblages at different spatial scales and to test the hypotheses that alpha and beta diversity of the assemblages, the abundance and the structure of epiphytic macroalgae, epilithic macroalgae, sessile macroinvertebrates and mobile macroinvertebrates associated to Cystoseira beds changed among scales. A hierarchical sampling design in a total of five sites across the Mediterranean Sea (Croatia, Montenegro, Sardinia,…
Assessing global range expansion in a cryptic species complex: insights from the red seaweed genus Asparagopsis (Florideophyceae)
2017
The mitochondrial genetic diversity, distribution and invasive potential of multiple cryptic operational taxonomic units (OTUs) of the red invasive seaweed Asparagopsis were assessed by studying introduced Mediterranean and Hawaiian populations. Invasive behavior of each Asparagopsis OTU was inferred from phylogeographic reconstructions, past historical demographic dynamics, recent range expansion assessments and future distributional predictions obtained from demographic models. Genealogical networks resolved Asparagopsis gametophytes and tetrasporophytes into four A. taxiformis and one A. armata cryptic OTUs. Falkenbergia isolates of A. taxiformis L3 were recovered for the first time in t…
Fish Health and Fisheries, Implications for Stock Assessment and Management: The Mediterranean Example
2012
Although fish health may influence key population-level processes, particularly those dealing with natural mortality, reproduction and growth, which in turn affect stock productivity, there has been little emphasis on the links between fish health and management of marine fisheries. This paper addresses this gap and illustrates how knowledge of fish health provides insight to marine fisheries biologists, stock assessment modellers and managers. The study demonstrates ways in which the consideration of condition (energy reserves) indicators and parasitism adds to improved stock assessment and fisheries management, also in situations of data shortage when standard methods cannot be applied, a…
Genetic and morphometric variations of Mediterranean hake,Merluccius merluccius,in the Strait of Sicily (central Mediterranean): Implications for sto…
2004
Allozyme, morphometric and growth analyses were applied to samples collected in the Strait of Sicily (central Mediterranean Sea) to test the hypothesis of the existence of a unique hake stock (Merluccius merluccius) in the study area. The level of genetic variation was detected from five polymorphic loci (ADH*, PGI-1; PGI-2*, PGM', SOD-1*). The average observed heterozygosity amounted to 0.421, while the average expected was 0.353. Weir & Cockerham statistics showed no heterogeneity, except for the single PGP locus (9 = 0.011; P 0.05). Morphometric analyses revealed some differentiation. Females showed different relationships in six out of eight morphometric indices with total length, while…
Properties of New Strawberry Lines Compared with Well-Known Cultivars in Winter Planting System Conditions
2017
In Southern Italy and Sicily, strawberry cultivation is dominated by international cultivars such as ‘Candonga Sabrosa’, ‘Florida Fortuna’, ‘Sabrina’ and ‘Sant Andreas’. The primary objective of our study was to compare the field performance of two experimental lines and four established cultivars in a Sicilian representative strawberry production area. The second objective was to compare the fruits physic-chemical nutraceutical characteristics of these genotypes in response to different postharvest fruit storage temperatures. A supporting genetic analysis, via SSR markers, was also performed in order to establish genotype correlations. Our study confirmed the high result of ‘Florida Fortun…
Parhyale plumicornis (Crustacea: Amphipoda: Hyalidae): is this an anti-lessepsian Mediterranean species? Morphological remarks, molecular markers and…
2016
Hyalid amphipods living in coastal marine habitats are frequently included in ecological studies. The systematics of this taxon has been subject to profound changes, with an emphasis on the North Pacific fauna. Since a proper species delimitation is a prerequisite in taxonomic and ecological studies, Parhyale plumicornis (Heller, 1866) has been herein re-described, showing the criticisms and mismatches of various characters, which were previously used in dichotomous keys. This species was collected for the first time off the western coast of Sicily Island (Italy: central Mediterranean Sea). The male is peculiar, due to the second antennae heavily setose posteriorly and bearing long tufts of…
Measuring the effects of temperature rise on Mediterranean shellfish aquaculture
2018
Abstract Shellfish aquaculture represents a worldwide valuable segment of the aquaculture market, spreading along the Mediterranean coasts, and is sensitive to the still unforeseen, poorly-known effects of climate change. Threats due to temperature rise can threaten the deployment and development of this sector, up until now recognised as the best candidate to mitigate the effects of fishery overexploitation. Here, we investigate the effects of temperature increase on the model species, Mytilus galloprovincialis, measuring outcomes from valve fragility (thickness) and condition index. Evidence of a reduction in the thickness of valves and the modulation condition of the mussels along with t…
Trophic relationships between two gurnards Trigla lucerna and Aspitrigla obscura from the western Mediterranean
1997
The feeding habits of Trigla lucerna L. (1758) and Aspitrigla obscura L. (1764) (Pisces: Triglidae), off the coast of the Gulf of Valencia (Spain), were investigated between October 1989 and January 1991. The two species examined in this study appear to have distinct feeding types, based on the species composition of prey and the frequency of occurrence of major food items. Tub gurnard had a more diverse diet and fed mainly on crustaceans (mysids and decapods), teleosts and molluscs, whilst long fin gurnard were less piscivorous and fed mainly on mysids and natantids. No significant differences were found in the annual variation of vacuity coefficient for either species. Diet composition in…
Phylogenetic relationships among tetraploid species of Bellevalia (Asparagaceae) endemic to south-central Mediterranean
2017
AbstractIn the south-central Mediterranean four tetraploid species of Bellevalia occur: B. dolichophylla, B. galitensis, B. mauritanica, and B. pelagica. Another group of plants, morphologically similar to B. dolichophylla, has been recently recovered in Zembra Island (Tunisia). A phylogenetic reconstruction involving all these tetraploid taxa was performed using both plastidial and nuclear markers (trnL-trnF and ITS, respectively). For all these taxa, an allopolyploid origin involving B. romana and B. dubia is supported. Regarding plants from Zembra, they may fall within the variability of B. dolichophylla.