3 research outputs found

    Occurrence of three dominant epibenthic dinoflagellates (Ostreopsis spp., Coolia monotis and Prorocentrum lima) in relation to biotic substrates and environmental factors in a highly dynamic ecosystem, the Strait of Gibraltar (Southwestern Mediterranean)

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    No studies have been carried out on the benthic harmful algal blooms (BHABs) along the Strait of Gibraltar in the Mediterranean, and little is known about the diversity of blooming species. Here, epibenthic dinoflagellates were monitored at least biweekly over 18 months (May 2019–November 2020) in Oued Lihoud, Cap Malabata and Dalia on the thalli of five dominant macrophytes and in the water column. This is the first report on the seasonal distribution of BHAB species hosted by natural biotic substrates in the Strait of Gibraltar, which is known for high hydrodynamics, major entry of Atlantic waters and important maritime traffic. Three BHAB dinoflagellates were observed in the surveyed areas: Ostreopsis spp., Coolia monotis and Prorocentrum lima. The analysis of all data at the three sites showed that Dictyota dichotoma was the most favourable macroalgae host for these benthic dinoflagellates. The highest cell densities were observed in Cap Malabata for Ostreopsis spp. (2.7 × 105 cells/g fresh weight in September 2020), P. lima (4.57 × 104 cells/g FW in September 2020) and C. monotis (4.07 × 104 cells/g FW in June 2019). Phosphate and temperature were positively correlated to the abundances of the studied thermophilic BHAB species. In contrast, negative correlations were recorded with salinity, ammonium, nitrite, nitrate, DIN, nitrogen/phosphate ratio and suspended material, attesting of the complex relationships between environmental factors and BHAB species dynamic in each marine ecosystem. Toxin analyses of the natural phytoplankton assemblage during BHABs showed the presence of only lipophilic toxins, namely okadaic acid and dinophysistoxins produced by P. lima. These BHABs species have to be isolated to establish monoclonal cultures for ribotyping and ecophysiological investigations

    Development of harmful algal blooms species responsible for lipophilic and amnesic shellfish poisoning intoxications in southwestern Mediterranean coastal waters

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    Mediterranean waters have undergone environmental changes during the last decades leading to various modifications of the structure of phytoplankton populations, especially Harmful Algal Blooms (HABs) species. Monitoring of the potentially toxic phytoplankton species was carried out biweekly in the western Mediterranean coast of Morocco from March 2018 to March 2019. Lipophilic Shellfish Toxins (LSTs) using LC-MS/MS and Domoic Acid (DA) using HPLC-UV were measured in the exploited mollusks, the cockle Acanthocardia tuberculata and the smooth clam Callista chione. We also determined the prevailing environmental factors in four surveyed sites (M'diq bay, Martil, Kaa Asras, and Djawn) selected to cover a variety of coastal ecosystems. Results showed that Pseudo-nitzschia spp. A DA producer species, was abundant with a pick of 50 × 103 cells l−1 on October 2018 in Djawn. Dinophysis caudata was the dominate Dinophysis species and showed a maximum density of 2200 cells l−1 on July in Djawn. Prorocentrum lima, an epibenthic dinoflagellate, appeared rarely in the water column with densities <80 cells l−1. Gonyaulax spinifera and Protoceratium reticulatum were found occasionally with a maximum density of 160 cells l−1. Karenia selliformis was detected only five times (<80 cells l−1) throughout the survey period. LC-MS/MS analyses revealed the presence of OA/DTX3, PTX-2, PTX-2 sa, and PTX-2 sa epi in the cockle at concentrations of up to 44.81 (OA/DTX-3+PTXs) ng g−1 meat. GYM-A was detected in the clam at concentrations of up to 4.22 ng g−1 meat. For the first time, AZAs and YTXs were detected in the southwestern Mediterranean with maximum values of 2.49 and 10.93 ng g−1 meat of cockle, respectively. DA was detected in moderate concentrations not exceeding 5.65 μg g−1 in both mollusks. Results showed that the observed toxic algae in the water column were responsible from the analysed toxins in the mollusks. It is likely that the southwestern Mediterranean waters could see the development of emergent species producing potent toxins (YTXs, AZAs, GYM-A). These dinoflagellates have to be isolated, ribotyped, and their toxin profiles determined

    Modernizing Training on Renewable Energies in the Maghreb Transfer of experience (MOMATE)

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    Le projet vise à développer une formation de type DUT (Diplôme Universitaire de Technologie) en ingénierie des Energies Renouvelables et à soutenir l'émergence de technopoles spécialisées dans les Energies Renouvelables. L'objectif est de développer des compétences permettant d'acquérir des connaissances de base sur la production d'électricité à partir d'énergies renouvelables (éolienne, solaire, photovoltaïque, etc.). El proyecto pretende desarrollar un programa de formación como el DUT (Diplôme Universitaire de Technologie) en ingeniería de Energías Renovables y apoyar la aparición de tecnopolos especializados en Energías Renovables. Para ello se pretende desarrollar competencias que permitan adquirir conocimientos básicos sobre la producción de energía eléctrica a partir de energías renovables (eólica, solar, fotovoltaica, etc.)The project aims to develop a DUT (University Diploma of Technology) type training in Renewable Energies engineering and to support the emergence of technology parks specializing in Renewable Energies. The objective is to develop skills allowing to acquire basic knowledge on the production of electricity from renewable energies (wind, solar, photovoltaic, etc.). The project intends to launch a training program such as the DUT (University Diploma of Technology) in Renewable Energy Engineering and to support the appearance of engineers specializing in Renewable Energy. Para ello claims to desarrollar competences that allow to acquire basic knowledge sober the production of electrical energy from renewable energies (electrical, solar, photovoltaic, etc.)MOMAT
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