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2021 ◽  
Vol 66 (2) ◽  
pp. 141-154
Author(s):  
Małgorzata Mazur

The Sabina section is one of the three groups in the Juniperus genus and the most diverse. The variability of Mediterranean junipers from the Sabina section is related to their Tertiary and Pleistocene migrations and long-term isolations. Their contemporary taxonomic and geographic diversity was influenced by important events such as the migration of continents, the disappearance of Tethys, orogenic movements or the Messinian salinity crisis. The results of morphological measurements of seed cones, seeds and branchlets with leaves of 19 populations of Juniperus phoenicea complex, J. excelsa s.s., J. thurifera subsp. thurifera and subs. africana, J. foetidissima and J. sabina var. sabina and var. balkanensis were statistically compiled using univariate statistics and multivariate analysis. The most important characters differentiating the populations within the taxa were the thickness of the branchlet and the cone diameter, while between the taxa the ratio of cone diameter to the width of the seeds and the number of seeds per cone were used for speciation. J. phoenicea complex is distinguished from the other studied taxa by the greatest number of characters. J. foetidissima, J. sabina var. sabina and J. canariensis are characterized by the highest variability of morphological characters, while J. excelsa and J. sabina var. balkanensis – the lowest. The studies confirmed the ancient nature of the J. phoenicea complex in relation to other taxa from the Sabina section, as a result of an earlier detachment from the ancestor, and no loss of variability due to the effects of colonization and isolation in J. canariensis. In addition, the similarity of J. sabina and J. thurifera was demonstrated, which would confirm the descent from a common ancestor and similar migration routes from the center of Europe towards the Iberian Peninsula, as well as further differentiation of J. thurifera into subspecies caused by isolation due to the opening of the Strait of Gibraltar. The distinctiveness of J. foetidissima from all the other analyzed taxa was also confirmed, and some morphological similarity was shown, proving the original character of J. excelsa s.s. and its similarity to the J. phoenicea complex in this respect.


2021 ◽  
Vol 66 (2) ◽  
pp. 133-140
Author(s):  
Katarzyna Marcysiak

The morphological features of plants, which were the basis of taxonomic solutions in the past, are now sometimes less appreciated due to the intensive development of genetic methods. The present review looks at the results of the research on the taxonomy of plants carried out by the team led by A. Boratyński. The team characterized the taxonomic and geographical differentiation of some species of the genera Abies, Juniperus, Pinus, Cupressus, Cedrus, as well as several others. Many of these studies were carried out in the Mediterranean area due to its importance for biodiversity. The results allowed unravelling taxonomic ambiguities, emphasizing the importance of geographic barriers in shaping variability, e.g., the Strait of Gibraltar or the Aegean Sea, and highlighting the role of mountain ranges as refuges, e.g., the Taurus and Anti-Taurus Mountains. All of the results obtained with biometrics were confirmed by genetic methods by different authors. Detailed research allowed the publication of a new name, Juniperus thurifera subsp. africana (Maire) Romo & Boratyński, stat. nov., and restoration of species status for the dubious taxon Juniperus canariensis. The review shows that relying on the research of a large number of correctly sampled populations and correctly selected differentiated characteristics of plants allows the generation of reliable results.


2021 ◽  
Vol 8 ◽  
Author(s):  
David Curbelo-Hernández ◽  
J. Magdalena Santana-Casiano ◽  
Aridane González González ◽  
Melchor González-Dávila

The seasonal and spatial variability of the CO2 system and air-sea fluxes were studied in surface waters of the Strait of Gibraltar between February 2019 and March 2021. High-resolution data was collected by a surface ocean observation platform aboard a volunteer observing ship. The CO2 system was strongly influenced by temperature and salinity fluctuations forced by the seasonal and spatial variability in the depth of the Atlantic–Mediterranean Interface layer and by the tidal and wind-induced upwelling. The changes in seawater CO2 fugacity (fCO2,sw) and fluxes were mainly driven by temperature despite the significant influence of non-thermal processes in the southernmost part. The thermal to non-thermal effect ratio (T/B) reached maximum values in the northern section (>1.8) and minimum values in the southern section (<1.30). The fCO2,sw increased with temperature by 9.02 ± 1.99 μatm °C–1 (r2 = 0.86 and ρ = 0.93) and 4.51 ± 1.66 μatm °C–1 (r2 = 0.48 and ρ = 0.69) in the northern and southern sections, respectively. The annual cycle of total inorganic carbon normalized to a constant salinity of 36.7 (NCT) was assessed. Net community production processes described 93.5–95.6% of the total NCT change, while air-sea exchange and horizontal and vertical advection accounted for <4.6%. The fCO2,sw in the Strait of Gibraltar since 1999 has been fitted to an equation with an interannual trend of 2.35 ± 0.06 μatm year–1 and a standard error of estimate of ±12.8 μatm. The seasonality of the air-sea CO2 fluxes reported the behavior as a strong CO2 sink during the cold months and as a weak CO2 source during the warm months. Both the northern and the southern sections acted as a net CO2 sink of −0.82 and −1.01 mol C m–2 year–1, respectively. The calculated average CO2 flux for the entire area was −7.12 Gg CO2 year–1 (−1.94 Gg C year–1).


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Luis Machado ◽  
D. James Harris ◽  
Daniele Salvi

Abstract Background The contribution of North Africa to the assembly of biodiversity within the Western Palaearctic is still poorly documented. Since the Miocene, multiple biotic exchanges occurred across the Strait of Gibraltar, underlying the high biogeographic affinity between the western European and African sides of the Mediterranean basin. We investigated the biogeographic and demographic dynamics of two large Mediterranean-adapted snakes across the Strait and assess their relevance to the origin and diversity patterns of current European and North African populations. Results We inferred phylogeographic patterns and demographic history of M. monspessulanus and H. hippocrepis, based on range-wide multilocus data, combined with fossil data and species distribution modelling, under present and past bioclimatic envelopes. For both species we identified endemic lineages in the High Atlas Mountains (Morocco) and in eastern Iberia, suggesting their persistence in Europe during the Pleistocene. One lineage is shared between North Africa and southern Iberia and likely spread from the former to the latter during the sea-level low stand of the last glacial stage. During this period M. monspessulanus shows a sudden demographic expansion, associated with increased habitat suitability in North Africa. Lower habitat suitability is predicted for both species during interglacial stages, with suitable areas restricted to coastal and mountain ranges of Iberia and Morocco. Compiled fossil data for M. monspessulanus show a continuous fossil record in Iberia at least since the Pliocene and throughout the Pleistocene. Conclusions The previously proposed hypothesis of Pleistocene glacial extinction of both species in Europe is not supported based on genetic data, bioclimatic envelopes models, and the available fossil record. A model of range retraction to mountain refugia during arid periods and of glacial expansion (demographic and spatial) associated to an increase of Mediterranean habitats during glacial epochs emerges as a general pattern for mesic vertebrates in North Africa. Moreover, the phylogeographic pattern of H. hippocrepis conforms to a well-established biogeographic partition between western and eastern Maghreb.


2021 ◽  
Vol 0 (0) ◽  
Author(s):  
João Faria ◽  
Afonso C.L. Prestes ◽  
Ignacio Moreu ◽  
Gustavo M. Martins ◽  
Ana I. Neto ◽  
...  

Abstract The present study reports the recent occurrence and expansion of Rugulopteryx okamurae in the Azores archipelago (NE Atlantic). Morphological and molecular characters confirmed the species identification. Quick surveys around the island of São Miguel showed that it has successfully colonized the island and is quickly expanding. In some locations, R. okamurae is currently the dominant organism smothering all other benthic biota and posing a serious threat to the benthic ecosystems across the region. The species first record dates from 2019 near the main harbour of the island, suggesting that its introduction was driven by human-assisted transport, via boat ballast waters or adhered to ship hulls and likely originating from the Mediterranean populations that have been proliferating in recent years across the Strait of Gibraltar.


Author(s):  
José Antonio Ponce-Blandón ◽  
Rocío Romero-Castillo ◽  
Nerea Jiménez-Picón ◽  
Juan Carlos Palomo-Lara ◽  
Aurora Castro-Méndez ◽  
...  

Background: The migratory flow from the African continent to Europe is intense and the European countries should apply a humanitarian, health and social response to this emerging problem. Migrants coming from Africa to Europe are a very vulnerable population. Healthcare professionals should be prepared for answering their needs from a transcultural approach, which requires a better understanding of this phenomenon. Thus, the aim of this study was to improve nursing and healthcare professionals’ awareness and better understanding of migrant life experiences during the migration journey. An exploratory descriptive qualitative research was conducted. In-depth interviews were conducted involving four key informants and content analysis were performed with the transcriptions. Results: Three themes merged: life situations in their countries of origin; motivations that led them to undertake the migratory journey; and experiences they lived during the migratory journey. The results described the dramatic experience and motivations for crossing the strait of Gibraltar from Africa to Europe, including feelings, fears, hopes and lived experiences. The determination of immigrants to fight for a better life opportunity and the physical damage and psychological consequences they suffer were revealed. Conclusions: This study would help healthcare professionals to better understand this complex reality and deliver culturally adapted care. Knowledge of the starting reality of these populations can help health professionals to incorporate a cross-cultural approach that improves the relational, ethical and affective competences to provide quality care to the migrant population, as well as the development of health measures to fight against inequalities suffered by these population groups.


2021 ◽  
pp. 1-9
Author(s):  
Bernard M. Landau ◽  
Carlos Marques da Silva

Abstract The cancellarid genus Sveltia Jousseaume, 1887, is widespread in western European and North African Neogene marine fossil assemblages. In Pliocene deposits it is commonly represented by Sveltia varicosa (Brocchi, 1814), which until recently was considered a widely distributed taxon in the Mediterranean Sea and adjacent Atlantic faunas. A recent review of the species from the Pliocene of Italy and Spain (Guadalquivir Basin), leading to the erection of S. confusa, prompted the reassessment of the Sveltia material from the Atlantic Pliocene of the Portuguese Mondego Basin and the subsequent description of Sveltia sofiae n. sp. Consequently, a mosaic of species has emerged from what was previously viewed as the broad Atlanto-Mediterranean range of the widespread and quite variable S. varicosa. From a biogeographic standpoint, it is now clear that S. varicosa was a Mediterranean species, occurring east of the Alboran Sea. Sveltia confusa had a mainly Atlantic distribution, from the French Pliocene Ligerian Gulf to the Gulf of Cadiz, at least, and straddling the Strait of Gibraltar into the Alboran Sea. Sveltia sofiae n. sp. was endemic to western Iberia, represented today only in the western Portuguese Mondego Basin. Sveltia is a thermophilic genus. Since early Pliocene times, because of northeastern Atlantic sea surface temperature decline, it underwent a southward range contraction, occurring today—in the eastern Atlantic—from Cape Blanc, Mauritania, south. This range reduction was coupled with the post mid-Piacenzian southward contraction of the Pliocene Mediterranean-West African tropical molluscan province and the consequent rise of the present-day Mediterranean-Moroccan subtropical province. UUID: http://zoobank.org/0cf3c73a-8d57-472e-87e4-f1ad065e5fb6.


2021 ◽  
Vol 19 ◽  
pp. 1-11
Author(s):  
Mark Baum

The Messinian Salinity Crisis (5.97-5.33Ma) may be one of the most significant periods of sea-level change in recent geologic history. During this period, evaporite deposition throughout the Mediterranean basin records a series of dramatic environmental changes as flow through the Strait of Gibraltar was restricted. In the first stage of evaporite deposition, cycles of gypsum appear in shallow basins on the margins of the Mediterranean. The complex environmental history giving rise to these cycles has been investigated for decades but remains controversial. Notably, whether the evaporites are connected to significant changes in Mediterranean sea level is an open question. In one proposed model, competition between tectonic uplift and erosion at the Strait of Gibraltar gives rise to selfsustaining sea-level oscillations—limit cycles—which trigger evaporite deposition. Here I show that limit cycles are not a robust result of the proposed model and discuss how any oscillations produced by this model depend on an unrealistic formulation of a key model equation. First, I simplify the model equations and test whether limit cycles are produced in 64 million unique combinations of model parameters, finding oscillations in only 0.2% of all simulations. Next, I examine the formulation of a critical model equation representing stream channel slope over the Strait of Gibraltar, concluding that a more realistic formulation would render sea-level limit cycles improbable, if not impossible, in the proposed model.


Water ◽  
2021 ◽  
Vol 13 (16) ◽  
pp. 2306
Author(s):  
Sandrine Ruitton ◽  
Aurélie Blanfuné ◽  
Charles-François Boudouresque ◽  
Dorian Guillemain ◽  
Valérie Michotey ◽  
...  

The temperate Northwest Pacific brown alga Rugulopteryx okamurae (Dictyotales, Phaeophyceae) was first discovered in 2002 in the Mediterranean Sea in the Thau coastal lagoon (Occitania, France) and then again in 2015 along the southern side of the Strait of Gibraltar, where it was assigned with invasive status. We report here on the first occurrence of the species in the Northwest Mediterranean Sea in Calanques National Park (Marseille, France) in 2018. By 2020, a large population had developed, extending over 9.5 km of coastline, including highly protected no-take zones. The seafood trade, with R. okamurae used as packing material for sea urchin Paracentrotus lividus shipments from Thau Lagoon, could be the vector of its introduction into the Marseille area. As observed in the Strait of Gibraltar, R. okamurae is spreading rapidly along the Marseille coasts, suggesting an invasive pathway. The subtidal reefs are densely carpeted with R. okamurae, which overgrows most native algal species. Fragments of the alga are continuously detached by wave actions and currents, sedimenting on the seabed and potentially clogging fishing nets, and thus, impacting artisanal fishing or washing up on the beaches, where they rot and raise concern among local populations.


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