Forty-five ostracod species were identified for the first time in the Tahadart estuary (NW Morocc... more Forty-five ostracod species were identified for the first time in the Tahadart estuary (NW Morocco). They can be grouped into five different ecological assemblages, which characterise four estuarine ecozones. A first ecozone occurs in temporary waters located ...
Ostracodes populations have been studied in 19 samples from the upper Neogene of the Atlantic coa... more Ostracodes populations have been studied in 19 samples from the upper Neogene of the Atlantic coast of NW of Morocco, between Tangier and Asilah. One hundred and two species belonging to 53 genera have been indentified. Analysis of the species assemblages allowed to reconstruct the palaeoenvironmental evolution of these deposits. This begins with the transgression of the upper Tortonian which
In the recent years, the frequency and the geographic distribution of jellyfish blooms have been ... more In the recent years, the frequency and the geographic distribution of jellyfish blooms have been increased in the Mediterranean northwest coastline of Morocco. Since 2011 this area has been subjected to successive blooms and stranding of Pelagia noctiluca. Our research was aimed to study the reasons of jellyfish blooms and to predict their stranding in our coastline. We have evaluated three parameters that we are suspecting to be responsible of Jellyfish blooms and stranding on the northern coast of the Mediterranean Sea in Morocco. The evaluation of the relations between sea surface temperature, waves height and the wind direction causing the stranding of Jellyfish, demonstrated that the correlation scores were found to be statistically significant with r(33) =0.445, p < 0.01, for sea surface temperature (°C) and r(33) =0. 694, p < 0.001 for waves height (m). Moreover a one-way analysis of variance (ANOVA) was calculated on wind direction causing stranding of jellyfish; the analysis was found to be very significant, F (1, 31) = 25.823, p = 0.001.
An overview of the Neogene euryhaline leptocytherids from Italian and Spanish basins is reported,... more An overview of the Neogene euryhaline leptocytherids from Italian and Spanish basins is reported, together with their chronological and geographical distributions. Eight genera (or subgenera) have been considered: Mediocytherideis s.s., M. (Sylvestra), Chartocythere, Leptocythere, Tavanicythere, Amnicythere, Euxinocythere s.s. and E. (Maeotocythere). The study has shown that these leptocytherids could be a valuable biochronological tool in both marginal marine and the athalassic saline environments, since, even at generic level, they show separate temporal distributions. For example, the presence of Chartocythere and Euxinocythere s.s. in the Mediterranean seems to be limited to the Late Serravallian; Tavanicythere seems to have been exclusively distributed during the Late Miocene, with different species spanning the Late Tortonian and Early Messinian; M. (Sylvestra) seems to attain its maximum diversity in the same time-interval; the widespreading of Amnicythere and E. (Maeotocythere) in the Mediterranean marks the Latest Messinian lago-mare event (about 5.5-5.3 Ma); the important radiation of Leptocythere characterises the Pliocene. Moreover, a comparative analysis between Neogene Mediterranean and Paratethyan leptocytherids has shown that the geographical and stratigraphical distribution of the eight genera analysed matches the palaeogeographic events that affected the Peri-Tethyan realm during Neogene.
L'étude de l'ostracofaune dans les sédiments de surface permet d'obtenir des informations sur les... more L'étude de l'ostracofaune dans les sédiments de surface permet d'obtenir des informations sur les processus sédimentaires récents à actuels de la marge méditerranéenne marocaine (partie occidentale de la Mer d'Alboran). A l'exception des embouchures deltaïques, où les ostracodes sont très rares et d'origine continentale, les 43 espèces et 35 genres récoltés et déterminés caractérisent les différents étages bathymétriques de la zone d'étude. La distribution quantitative et qualitative de la microfaune est principalement contrôlée par l'influence des apports par les oueds, le régime hydrodynamique (échanges entre l'Atlantique et la Méditerranée), la bathymétrie et le contexte morphologique.
Jellyfish stranding one of the most important, and complicated topics that scientists all over th... more Jellyfish stranding one of the most important, and complicated topics that scientists all over the world are try to understand. Obviously, Jellyfish spatiotemporal dynamics are highly variable, as well blooms occur irregularly are difficult to predict [1,2]. Pelagia noctiluca (Forsskål 1775) most common jellyfish species in the Mediterranean waters, it is widely distributed from the warm subtropical waters of the Gulf of Mexico and the Mediterranean Sea to the temperate waters of the North Sea [3-6] and up to 4°C of latitude [7,8].
En este trabajo se realiza el primer estudio detallado de la litologia y la ostracofauna del Plio... more En este trabajo se realiza el primer estudio detallado de la litologia y la ostracofauna del Plioceno inferior de la cuenca de Tetuan (Marruecos, norte-oocidental). Se identifico un total de ciento treinta especies, reagrupados en cuarenta y nueve generos. Se describe y figura una especie nueva, Cytherelloidea tetuanienses n. Sp., junto con varias que se han quedado en nomenclatura abierta. El reconocimiento de cinco asociaciones de Ostracodos, y el estudio de sus caracteristicas cuantitativas, han permitido la discusion del significado paleobatimetrico y paleoecologico de la microfauna investigada y el ambiente de deposicion de los sedimentos estudiados.
Foraminifer assemblages from several surface samples of the Tahadart estuary, in the Atlantic coa... more Foraminifer assemblages from several surface samples of the Tahadart estuary, in the Atlantic coast of Northwestern Morocco, have been analysed for the first time. A total of seventy seven species have been taxonomically identified, fortytwo of which contained live specimens in the time of sampling. Dominant assemblage is composed of the species Ammonia tepida and Haynesina germanica, which are accompanied by Lobatula lobatula and Bolivina pseudoplicata in the mouth of the estuary and by Jadammina macrescens in the middle and higher marsh areas. The high diversity index and the great number of species coming from the marine shelf are indicative of the strong energy of this estuary, with an open connection to the sea, even in channels far from the coastal area.
Ostracodes populations have been studied in 19 samples from the upper Neogene of the Atlantic coa... more Ostracodes populations have been studied in 19 samples from the upper Neogene of the Atlantic coast of NW of Morocco, between Tangier and Asilah. One hundred and two species belonging to 53 genera have been indentified. Analysis of the species assemblages allowed to reconstruct the palaeoenvironmental evolution of these deposits. This begins with the transgression of the upper Tortonian which
Forty-five ostracod species were identified for the first time in the Tahadart estuary (NW Morocc... more Forty-five ostracod species were identified for the first time in the Tahadart estuary (NW Morocco). They can be grouped into five different ecological assemblages, which characterise four estuarine ecozones. A first ecozone occurs in temporary waters located ...
En este trabajo se realiza el primer estudio detallado de la litologia y la ostracofauna del Plio... more En este trabajo se realiza el primer estudio detallado de la litologia y la ostracofauna del Plioceno inferior de la cuenca de Tetuan (Marruecos, norte-oocidental). Se identifico un total de ciento treinta especies, reagrupados en cuarenta y nueve generos. Se describe y figura una especie nueva, Cytherelloidea tetuanienses n. Sp., junto con varias que se han quedado en nomenclatura abierta. El reconocimiento de cinco asociaciones de Ostracodos, y el estudio de sus caracteristicas cuantitativas, han permitido la discusion del significado paleobatimetrico y paleoecologico de la microfauna investigada y el ambiente de deposicion de los sedimentos estudiados.
Forty-five ostracod species were identified for the first time in the Tahadart estuary (NW Morocc... more Forty-five ostracod species were identified for the first time in the Tahadart estuary (NW Morocco). They can be grouped into five different ecological assemblages, which characterise four estuarine ecozones. A first ecozone occurs in temporary waters located ...
Ostracodes populations have been studied in 19 samples from the upper Neogene of the Atlantic coa... more Ostracodes populations have been studied in 19 samples from the upper Neogene of the Atlantic coast of NW of Morocco, between Tangier and Asilah. One hundred and two species belonging to 53 genera have been indentified. Analysis of the species assemblages allowed to reconstruct the palaeoenvironmental evolution of these deposits. This begins with the transgression of the upper Tortonian which
In the recent years, the frequency and the geographic distribution of jellyfish blooms have been ... more In the recent years, the frequency and the geographic distribution of jellyfish blooms have been increased in the Mediterranean northwest coastline of Morocco. Since 2011 this area has been subjected to successive blooms and stranding of Pelagia noctiluca. Our research was aimed to study the reasons of jellyfish blooms and to predict their stranding in our coastline. We have evaluated three parameters that we are suspecting to be responsible of Jellyfish blooms and stranding on the northern coast of the Mediterranean Sea in Morocco. The evaluation of the relations between sea surface temperature, waves height and the wind direction causing the stranding of Jellyfish, demonstrated that the correlation scores were found to be statistically significant with r(33) =0.445, p < 0.01, for sea surface temperature (°C) and r(33) =0. 694, p < 0.001 for waves height (m). Moreover a one-way analysis of variance (ANOVA) was calculated on wind direction causing stranding of jellyfish; the analysis was found to be very significant, F (1, 31) = 25.823, p = 0.001.
An overview of the Neogene euryhaline leptocytherids from Italian and Spanish basins is reported,... more An overview of the Neogene euryhaline leptocytherids from Italian and Spanish basins is reported, together with their chronological and geographical distributions. Eight genera (or subgenera) have been considered: Mediocytherideis s.s., M. (Sylvestra), Chartocythere, Leptocythere, Tavanicythere, Amnicythere, Euxinocythere s.s. and E. (Maeotocythere). The study has shown that these leptocytherids could be a valuable biochronological tool in both marginal marine and the athalassic saline environments, since, even at generic level, they show separate temporal distributions. For example, the presence of Chartocythere and Euxinocythere s.s. in the Mediterranean seems to be limited to the Late Serravallian; Tavanicythere seems to have been exclusively distributed during the Late Miocene, with different species spanning the Late Tortonian and Early Messinian; M. (Sylvestra) seems to attain its maximum diversity in the same time-interval; the widespreading of Amnicythere and E. (Maeotocythere) in the Mediterranean marks the Latest Messinian lago-mare event (about 5.5-5.3 Ma); the important radiation of Leptocythere characterises the Pliocene. Moreover, a comparative analysis between Neogene Mediterranean and Paratethyan leptocytherids has shown that the geographical and stratigraphical distribution of the eight genera analysed matches the palaeogeographic events that affected the Peri-Tethyan realm during Neogene.
L'étude de l'ostracofaune dans les sédiments de surface permet d'obtenir des informations sur les... more L'étude de l'ostracofaune dans les sédiments de surface permet d'obtenir des informations sur les processus sédimentaires récents à actuels de la marge méditerranéenne marocaine (partie occidentale de la Mer d'Alboran). A l'exception des embouchures deltaïques, où les ostracodes sont très rares et d'origine continentale, les 43 espèces et 35 genres récoltés et déterminés caractérisent les différents étages bathymétriques de la zone d'étude. La distribution quantitative et qualitative de la microfaune est principalement contrôlée par l'influence des apports par les oueds, le régime hydrodynamique (échanges entre l'Atlantique et la Méditerranée), la bathymétrie et le contexte morphologique.
Jellyfish stranding one of the most important, and complicated topics that scientists all over th... more Jellyfish stranding one of the most important, and complicated topics that scientists all over the world are try to understand. Obviously, Jellyfish spatiotemporal dynamics are highly variable, as well blooms occur irregularly are difficult to predict [1,2]. Pelagia noctiluca (Forsskål 1775) most common jellyfish species in the Mediterranean waters, it is widely distributed from the warm subtropical waters of the Gulf of Mexico and the Mediterranean Sea to the temperate waters of the North Sea [3-6] and up to 4°C of latitude [7,8].
En este trabajo se realiza el primer estudio detallado de la litologia y la ostracofauna del Plio... more En este trabajo se realiza el primer estudio detallado de la litologia y la ostracofauna del Plioceno inferior de la cuenca de Tetuan (Marruecos, norte-oocidental). Se identifico un total de ciento treinta especies, reagrupados en cuarenta y nueve generos. Se describe y figura una especie nueva, Cytherelloidea tetuanienses n. Sp., junto con varias que se han quedado en nomenclatura abierta. El reconocimiento de cinco asociaciones de Ostracodos, y el estudio de sus caracteristicas cuantitativas, han permitido la discusion del significado paleobatimetrico y paleoecologico de la microfauna investigada y el ambiente de deposicion de los sedimentos estudiados.
Foraminifer assemblages from several surface samples of the Tahadart estuary, in the Atlantic coa... more Foraminifer assemblages from several surface samples of the Tahadart estuary, in the Atlantic coast of Northwestern Morocco, have been analysed for the first time. A total of seventy seven species have been taxonomically identified, fortytwo of which contained live specimens in the time of sampling. Dominant assemblage is composed of the species Ammonia tepida and Haynesina germanica, which are accompanied by Lobatula lobatula and Bolivina pseudoplicata in the mouth of the estuary and by Jadammina macrescens in the middle and higher marsh areas. The high diversity index and the great number of species coming from the marine shelf are indicative of the strong energy of this estuary, with an open connection to the sea, even in channels far from the coastal area.
Ostracodes populations have been studied in 19 samples from the upper Neogene of the Atlantic coa... more Ostracodes populations have been studied in 19 samples from the upper Neogene of the Atlantic coast of NW of Morocco, between Tangier and Asilah. One hundred and two species belonging to 53 genera have been indentified. Analysis of the species assemblages allowed to reconstruct the palaeoenvironmental evolution of these deposits. This begins with the transgression of the upper Tortonian which
Forty-five ostracod species were identified for the first time in the Tahadart estuary (NW Morocc... more Forty-five ostracod species were identified for the first time in the Tahadart estuary (NW Morocco). They can be grouped into five different ecological assemblages, which characterise four estuarine ecozones. A first ecozone occurs in temporary waters located ...
En este trabajo se realiza el primer estudio detallado de la litologia y la ostracofauna del Plio... more En este trabajo se realiza el primer estudio detallado de la litologia y la ostracofauna del Plioceno inferior de la cuenca de Tetuan (Marruecos, norte-oocidental). Se identifico un total de ciento treinta especies, reagrupados en cuarenta y nueve generos. Se describe y figura una especie nueva, Cytherelloidea tetuanienses n. Sp., junto con varias que se han quedado en nomenclatura abierta. El reconocimiento de cinco asociaciones de Ostracodos, y el estudio de sus caracteristicas cuantitativas, han permitido la discusion del significado paleobatimetrico y paleoecologico de la microfauna investigada y el ambiente de deposicion de los sedimentos estudiados.
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