"Spéciation" des trois éléments trace mercure, plomb et cadmium dans les sédiments marins des zones côtières libanaises

PARIS-AgroParisTech Centre Paris (751052302) / SudocSudocFranceF

La Terminologie arabe du génie génétique

LYON2/BRON-BU (690292101) / SudocSudocFranceF

PB, CD AND CU DISTRIBUTION AND MOBILITY IN MARINE SEDIMENTS FROM TWO PORTS IN LEBANON: BEIRUT ARMY NAVAL PORT AND TRIPOLI FISHING PORT

Abi-Ghanem Carine, Celine Mahfouz, Gaby Khalaf, Elie Najjar, Henri El-Zakhem and Rima Manneh. 2016. Pb, Cd and Cu distribution and mobility in marine sediments from two ports in Lebanon: Beirut army naval port and Tripoli fishing port. Lebanese Science Journal, 17(1): 59-75. Lead, cadmium and copper distribution and mobility in superficial sediments collected from the Beirut army navel port and Tripoli fishing port in Lebanon were studied. Results showed relatively high concentrations of Pb (181.4-518.9μg.g-1), Cd (1.33-6.7μg.g-1), and Cu (141-246.8μg.g-1) in sediments inside the port of Beirut. In Tripoli fishing port, Pb and Cd concentrations in sampled sediments were lower. However, higher Cu concentrations (up to 524.5 μg.g-1) were detected in Tripoli sediments. The extractability of Cd, Pb and Cu from the sediments of Beirut and Tripoli port were studied by applying EDTA 0.05M and CaCl2 0.01M extractions for two extraction times: 1h and 24h. These extractions showed that Cd and Pb were highly mobilized by EDTA. However, only Pb was mobilized by CaCl2 from sediments collected in Beirut military port

Multi-approach analysis to assess diet of harbour porpoises Phocoena phocoena in the southern North Sea

International audienceOver the past decade, the distribution of harbour porpoises Phocoena phocoena has undergone a southward shift in the North Sea, which has led to an increase in the number of stranded porpoises in its southern part. Since the changes in distribution and relative abundance of porpoises may be linked to the changes in prey availability, the aim of the present work was to investigate whether any changes in the feeding habits of harbour porpoises along the North Sea occurred in the past decade. The diet of harbour porpoises stranded along the southern North Sea (northern France and Belgian coast) was assessed through 3 complementary methods: stomach content analysis, stable isotopes (carbon and nitrogen) analysis determined from muscle samples, and fatty acids analysis determined from blubber samples. Fatty acid patterns and stable isotope values from 52 porpoises were compared to 14 potential prey species collected from the southern North Sea. Our results showed that the diet of porpoises along the southern North Sea comprises fish species that are among the most abundant and widely distributed in the area, except for the sardine Sardina pilchardus that appeared to be a new potential prey. Moreover, our results suggested that the decline in sandeel (Ammodytidae) in the northern parts of the North Sea along with the re-invasion of the southern North Sea by sardine species might affect the distribution of harbour porpoises

Distribution and diagenesis of trace metals in marine sediments of a coastal Mediterranean area: St-Georges Bay (Lebanon)

International audienceSt-Georges Bay (Lebanon) is an open bay, to the Mediterranean Sea and it is exposed to numerous anthropogenic activities such as industrial effluents, non-treated wastewater discharge and maritime activities leading an increasing chemical contamination especially with trace metals. Contamination with trace metals (Cu, Cd, Co, Pb, As, Ag and Hg) and the influence of early diagenesis on their distribution are studied on both sediments and waters transect. For this purpose, sediment cores were collected, then treated under inert atmosphere to retrieve pore waters and solid fraction. The area appeared to be seriously impacted by the transport through Beirut River and/or by direct inputs, and the recent landscaping done with dumpsite material. The sediments showed a significant level of contamination. Element mobility was studied by selective extraction on sediments. The mobility of the studied trace elements from solid fraction to pore waters is controlled by Fe/Mn cycle and organic matter