scholarly journals Revision of the Genus Schizoretepora (Bryozoa, Cheilostomatida) from the Atlantic-Mediterranean region

Author(s):  
Teresa Madurell ◽  
Mary Spencer Jones ◽  
Mikel Zabala

We examined the type specimens and historical collections holding puzzling Atlantic and Mediterranean material belonging to the genus Schizoretepora Gregory, 1893. We performed a detailed study of the colonial characters and re-describe the resulting species and those that have rarely been found or have poor original descriptions. As a result of this revision, nine species are found in the northeast Atlantic and Mediterranean. Six of them are re-described and illustrated: S. aviculifera (Canu & Bassler, 1930), S. calveti d’Hondt, 1975, S. imperati (Busk, 1884), S. sp. nov.? (= S. imperati sensu O’Donoghue & de Watteville 1939) (in open nomenclature, specimen lacks ovicells), S. pungens (Canu & Bassler, 1928) and S. solanderia (Risso, 1826). For S. dentata (Calvet, 1931), no material remains; furthermore, S. hassi Harmelin, Bitar & Zibrowius, 2007 and S. serratimargo (Hincks, 1886) have recently been described and redescribed, respectively. This new arrangement attains a coherent geographical distribution: S. imperati seems restricted to the eastern Atlantic, S. dentata and S. calveti are deepwater species from Atlantic islands, S. pungens and S. aviculifera dwell on the African coasts of the Western Mediterranean, S. hassi and S. sp. nov.? (=S. imperati sensu O’Donogue & de Wateville 1939) are confined to the Eastern Mediterranean, and S. solanderia and S. serratimargo live on the European coasts of the Mediterranean.

1905 ◽  
Vol 2 (10) ◽  
pp. 462-467 ◽  
Author(s):  
C. I. Forsyth Major

In a former publication I have dealt with the anatomy of Prolagus sardus (Wagn.), from the Sardinian and Corsican Pleistocene, in comparison with that of its Tertiary relatives. The following pages deal with the geographical distribution of Pleistocene Prolagus and its bearing on more general questions.When Ouvier discovered, in the ossiferous breccia of Corsica, remains of a ‘Lagomys,’ which he believed to be closely related to the Siberian Lagomys alpinus, he also suggested other analogies between the faunas of the two regions—Siberia and Corsica (as well as Sardinia), and commented upon the supposed relationship between the insular Mouflon and the Siberian Argali. Similar views were expressed by B. Wagner.Pumpelly, Loeard, and Lortet sought to establish a connection between a supposed Corsioan ‘ice-age,’ as attested by the trace of ancient glaciers, and the former existence in the island of a supposed inhabitant of cold regions, the Lagomys corsicanus. Hensel had, however, shown before, in 1856, that the affinities of Lagomys sardus from the Sardinian bone breccia are not with the recent Lagomys (Ogotona), but with a Miocene type, for which he proposed the generic name Myolagus (antedated by Prolagus, Pormel). He was in consequence inclined to assume a Tertiary age for the breccias in which the Prolagus occurred (and, indeed, for the whole of the Mediterranean bone breccias). A similar view has again been brought forward of late years.I myself pointed out (1) that the Corsican Lagomys likewise belonged to the genus Prolagus, as indeed had already been suspected by Hensel from his inspection of Cuvier's figures; (2) that the Tertiary age of the Corsican and Sardinian breccias could not be upheld, above all, because the mollusca occurring in them, as Loeard bad shown to be the case in the ossiferous breccia of Toga, near Bastia, are still living in the neighbourhood.


2018 ◽  
Vol 46 (1) ◽  
pp. 261-289 ◽  
Author(s):  
Leigh Royden ◽  
Claudio Faccenna

The Late Cenozoic tectonic evolution of the Mediterranean region, which is sandwiched between the converging African and European continents, is dominated by the process of subduction orogeny. Subduction orogeny occurs where localized subduction, driven by negative slab buoyancy, is more rapid than the convergence rate of the bounding plates; it is commonly developed in zones of early or incomplete continental collision. Subduction orogens can be distinguished from collisional orogens on the basis of driving mechanism, tectonic setting, and geologic expression. Three distinct Late Cenozoic subduction orogens can be identified in the Mediterranean region, making up the Western Mediterranean (Apennine, external Betic, Maghebride, Rif), Central Mediterranean (Carpathian), and Eastern Mediterranean (southern Dinaride, external Hellenide, external Tauride) Arcs. The Late Cenozoic evolution of these orogens, described in this article, is best understood in light of the processes that govern subduction orogeny and depends strongly on the buoyancy of the locally subducting lithosphere; it is thus strongly related to paleogeography. Because the slow (4–10 mm/yr) convergence rate between Africa and Eurasia has preserved the early collisional environment, and associated tectonism, for tens of millions of years, the Mediterranean region provides an excellent opportunity to elucidate the dynamic and kinematic processes of subduction orogeny and to better understand how these processes operate in other orogenic systems.


2008 ◽  
Vol 17 ◽  
pp. 87-91 ◽  
Author(s):  
A. V. Mehta ◽  
S. Yang

Abstract. Climatological features of mesoscale rain activities over the Mediterranean region between 5° W–40° E and 28° N–48° N are examined using the Tropical Rainfall Measuring Mission (TRMM) 3B42 and 2A25 rain products. The 3B42 rainrates at 3-hourly, 0.25°×0.25° spatial resolution for the last 10 years (January 1998 to July 2007) are used to form and analyze the 5-day mean and monthly mean climatology of rainfall. Results show considerable regional and seasonal differences of rainfall over the Mediterranean Region. The maximum rainfall (3–5 mm day−1) occurs over the mountain regions of Europe, while the minimum rainfall is observed over North Africa (~0.5 mm day−1). The main rainy season over the Mediterranean Sea extends from October to March, with maximum rainfall occurring during November–December. Over the Mediterranean Sea, an average rainrate of ~1–2 mm day−1 is observed, but during the rainy season there is 20% larger rainfall over the western Mediterranean Sea than that over the eastern Mediterranean Sea. During the rainy season, mesoscale rain systems generally propagate from west to east and from north to south over the Mediterranean region, likely to be associated with Mediterranean cyclonic disturbances resulting from interactions among large-scale circulation, orography, and land-sea temperature contrast.


Author(s):  
Bernhard Hausdorf ◽  
Sonja Bamberger ◽  
Frank Walther

Abstract We report an unusual biogeographical disjunction between the western and the eastern Mediterranean region. Cornu (Gastropoda: Helicidae) is a western Mediterranean land snail genus. It includes Cornu (Cornu) aspersum, which originated in north-western Africa and was distributed by humans for food or accidentally, first throughout the Mediterranean region and, subsequently, to all continents except Antarctica. It also includes three species belonging to the subgenus Erctella, which are all endemic to Sicily. We discovered a new species of Cornu on the Greek island of Crete. The morphological and molecular genetic analyses showed that the species from Crete is a disjunct representative of the subgenus Erctella. We hypothesize that the disjunction originated by a long-distance dispersal event of the ancestors of the Cretan species from Sicily by birds or by sea currents, perhaps facilitated by a tsunami or a similar event. The Cretan lineage separated from the Sicilian species in the Late Miocene or Early Pliocene. This divergence time is compatible with the hypothesis that the ancestor of Cornu cretense sp. nov. was washed from Sicily to Crete by the Zanclean flood that refilled the Mediterranean basin after it had dried up during the Messinian salinity crisis.


Author(s):  
Andrew Harding ◽  
Jean Palutikof

The Mediterranean region has a highly distinctive climate due to its position between 30 and 45°N to the west of the Euro-Asian landmass. With respect to the global atmospheric system, it lies between subtropical high pressure systems to the south, and westerly wind belts to the north. In winter, as these systems move equatorward, the Mediterranean basin lies under the influence of, and is exposed to, the westerly wind belt, and the weather is wet and mild. In the summer, as shown in Figure 3.1, the Mediterranean lies under subtropical high pressure systems, and conditions are hot and dry, with an absolute drought that may persist for more than two or three months in drier regions. Climates such as this are relatively rare, and the Mediterranean shares its winter wet/summer dry conditions with locations as distant as central Chile, the southern tip of Cape Province in South Africa, southwest Australia in the Southern Hemisphere, and central California in the Northern Hemisphere. All have in common their mid-latitude position, between subtropical high pressure systems and westerly wind belts. They all lie on the westerly side of continents so that, in winter, when the westerly wind belts dominate over their locations, they are exposed to rain-bearing winds. In the Köppen classification (Köppen 1936), these climates are known as Mediterranean (Type Cs, which is subdivided in turn into maritime Csb and continental Csa). The influence of the Mediterranean Sea means that the Mediterranean-type climate of the region extends much further into the continental landmass than elsewhere, and is not restricted to a narrow ocean-facing strip. Nevertheless, within the Mediterranean region climate is modified by position and topographic influences can be important. The proximity of the western Mediterranean to the Atlantic Ocean gives its climate a maritime flavour, with higher rainfall and milder temperatures throughout the year. The eastern Mediterranean lies closer to the truly continental influences of central Europe and Asia. Its climate is drier, and temperatures are hotter in summer and colder in winter than in the west. Annual rainfall is typically around 750 mm in Rome, but only around 400 mm in Athens.


2015 ◽  
Vol 3 (6) ◽  
pp. 3687-3732 ◽  
Author(s):  
U. Dayan ◽  
K. M. Nissen ◽  
U. Ulbrich

Abstract. This review discusses published studies of heavy rainfall events over the Mediterranean Basin, combining them in a more general picture of the dynamic and thermodynamic factors and processes producing heavy rain storms. It distinguishes the Western and Eastern Mediterranean in order to point at specific regional peculiarities. The crucial moisture for developing intensive convection over these regions can be originated not only from the adjacent Mediterranean Sea but also from distant upwind sources. Transport from remote sources is usually in the mid-tropospheric layers and associated with specific features and patterns of the larger scale circulations. The synoptic systems (tropical and extra-tropical) accounting for most of the major extreme precipitation events and the coupling of circulation and extreme rainfall patterns are presented. Heavy rainfall over the Mediterranean Basin is caused at times in concert by several atmospheric processes working at different atmospheric scales, such as local convection, upper-level synoptic-scale troughs, and meso-scale convective systems. Under tropical air mass intrusions, convection generated by static instability seems to play a more important role than synoptic-scale vertical motions. Locally, the occurrence of torrential rains and their intensity is dependent on factors such as temperature profiles and implied instability, atmospheric moisture, and lower-level convergence.


2015 ◽  
Vol 12 (8) ◽  
pp. 8459-8504 ◽  
Author(s):  
M. Fader ◽  
S. Shi ◽  
W. von Bloh ◽  
A. Bondeau ◽  
W. Cramer

Abstract. Irrigation in the Mediterranean is of vital importance for food security, employment and economic development. This study systematically assesses how climate change and increases in atmospheric CO2 concentrations may affect irrigation requirements in the Mediterranean region by 2080–2090. Future demographic change and technological improvements in irrigation systems are accounted for, as is the spread of climate forcing, warming levels and potential realization of the CO2-fertilization effect. Vegetation growth, phenology, agricultural production and irrigation water requirements and withdrawal were simulated with the process-based ecohydrological and agro-ecosystem model LPJmL after a large development that comprised the improved representation of Mediterranean crops. At present the Mediterranean region could save 35 % of water by implementing more efficient irrigation and conveyance systems. Some countries like Syria, Egypt and Turkey have higher saving potentials than others. Currently some crops, especially sugar cane and agricultural trees, consume in average more irrigation water per hectare than annual crops. Different crops show different magnitude of changes in net irrigation requirements due to climate change, being the increases most pronounced in agricultural trees. The Mediterranean area as a whole might face an increase in gross irrigation requirements between 4 and 18 % from climate change alone if irrigation systems and conveyance are not improved (2 °C global warming combined with full CO2-fertilization effect, and 5 °C global warming combined with no CO2-fertilization effect, respectively). Population growth increases these numbers to 22 and 74 %, respectively, affecting mainly the Southern and Eastern Mediterranean. However, improved irrigation technologies and conveyance systems have large water saving potentials, especially in the Eastern Mediterranean, and may be able to compensate to some degree the increases due to climate change and population growth. Both subregions would need around 35 % more water than today if they could afford some degree of modernization of irrigation and conveyance systems and benefit from the CO2-fertilization effect. Nevertheless, water scarcity might pose further challenges to the agricultural sector: Algeria, Libya, Israel, Jordan, Lebanon, Syria, Serbia, Morocco, Tunisia and Spain have a high risk of not being able to sustainably meet future irrigation water requirements in some scenarios. The results presented in this study point to the necessity of performing further research on climate-friendly agro-ecosystems in order to assess, on the one side, their degree of resilience to climate shocks, and on the other side, their adaptation potential when confronted with higher temperatures and changes in water availability.


2009 ◽  
Vol 3 (09) ◽  
pp. 654-659 ◽  
Author(s):  
Michael A. Borg ◽  
Barry D. Cookson ◽  
Peter Zarb ◽  
Elizabeth A. Scicluna ◽  
ARMed Steering Group & Collaborators *

Antimicrobial resistance has become a global threat to effective health care delivery. This is particularly the case within the Mediterranean region, where data from recent studies suggests the situation to be particularly acute. A better knowledge base, as well as a collaborative effort, is therefore required to address this ever increasing challenge to effective patient care. Over its four-year period, the Antibiotic Resistance Surveillance and Control in the Mediterranean Region (ARMed) project investigated the epidemiology of antimicrobial resistance, as well as its contributory factors, in a number of countries in the southern and eastern Mediterranean region through the collection of comparable and validated data. The project culminated in a consensus conference held in Malta in November 2006. The conference provided a forum for expert delegates to agree on a number of priority strategic recommendations that would be relevant to resistance containment efforts in the region. There was general agreement on the need for surveillance and audit to underpin any intervention to tackle antimicrobial resistance, both to monitor changing epidemiological trends in critical pathogens as well as to identify antibiotic consumption practices and effectiveness of prevention and control of health care associated infections. In addition, the importance to convey these data to key users was also stressed in all workshops, as was better education and training of health care workers. The recommendations also made it clear that ownership of the problem needs to be improved throughout the region and that resources, both financial as well as human, must be allocated by the respective policy makers in order to combat it.


2019 ◽  
Author(s):  
Piero Lionello ◽  
Dario Conte ◽  
Marco Reale

Abstract. Large positive and negative sea level anomalies at the coast of the Mediterranean Sea are linked to intensity and position of cyclones moving along the Mediterranean storm track, with dynamics involving different factors. This analysis is based on a model hindcast and considers nine coastal stations, which are representative of sea level anomalies with different magnitude and characteristics. When a shallow water fetch is present, the wind around the cyclone center is the main cause of sea level positive and negative anomalies, depending on its onshore or offshore direction. The inverse barometer effect produces a positive anomaly at the coast near the cyclone pressure minimum and a negative anomaly at the opposite side of the Mediterranean Sea, because a cross-basin mean sea level pressure gradient is associated to the presence of a cyclone. Further, at some stations, negative sea level anomalies are reinforced by a residual water mass redistribution within the basin, which is associated with a transient response to the atmospheric pressure forcing. Though the link between presence of a cyclone in the Mediterranean has comparable importance for positive and negative anomalies, the relation between cyclone position and intensity is stronger for the magnitude of positive events. Area of cyclogenesis, track of the central minimum and position at the time of the event differ depending on the location where the sea level anomaly occurs and on its sign. The western Mediterranean is the main cyclogenesis area for both positive and negative anomalies, overall. Atlantic cyclones mainly produce positive sea level anomalies in the western basin. At the easternmost stations, positive anomalies are caused by Cyclogenesis in the Eastern Mediterranean. North Africa cyclogeneses are a major source of positive anomalies at the central African coast and negative anomalies at the eastern Mediterranean and North Aegean coast.


2021 ◽  
Author(s):  
Johannes Vogel

<p>The ecosystems of the Mediterranean Basin are particularly prone to climate change and related alterations in climatic anomalies. The seasonal timing of climatic anomalies is crucial for the assessment of the corresponding ecosystem impacts; however, the incorporation of seasonality is neglected in many studies. We quantify ecosystem vulnerability by investigating deviations of the climatic drivers temperature and soil moisture during phases of low ecosystem productivity for each month of the year over the period 1999 – 2019. The fraction of absorbed photosynthetically active radiation (FAPAR) is used as a proxy for ecosystem productivity. Air temperature is obtained from the reanalysis data set ERA5 Land and soil moisture and FAPAR satellite products are retrieved from ESA CCI and Copernicus Global Land Service, respectively. Our results show that Mediterranean ecosystems are vulnerable to three soil moisture regimes during the course of the year. A phase of vulnerability to hot and dry conditions during late spring to midsummer is followed by a period of vulnerability to cold and dry conditions in autumn. The third phase is characterized by cold and wet conditions coinciding with low ecosystem productivity in winter and early spring. These phases illustrate well the shift between a soil moisture-limited regime in summer and an energy-limited regime in winter in the Mediterranean Basin. Notably, the vulnerability to hot and dry conditions during the course of the year is prolonged by several months in the Eastern Mediterranean compared to the Western Mediterranean. Our approach facilitates a better understanding of ecosystem vulnerability at certain stages during the year and is easily transferable to other study areas and ecoclimatological variables.</p>


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