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Marine, Lebanon

El Samad O.,National Council for Scientific Research | Aoun M.,National Council for Scientific Research | Nsouli B.,National Council for Scientific Research | Khalaf G.,Marine Research Center | Hamze M.,National Council for Scientific Research CNRS
Journal of Environmental Radioactivity

This investigation was carried out in order to assess the marine environmental radioactive pollution and the radiological impact caused by a large production plant of phosphate fertilizer, located in the Lebanese coastal zone. Natural radionuclides (238U, 235U, 232Th, 226Ra, 210Po, 210Pb, 40K) and anthropogenic 137Cs were measured by alpha and gamma spectrometry in seawater, sediment, biota and coastal soil samples collected from the area impacted by this industry. The limited environmental monitoring program within 2km of the plant indicates localized contamination with radionuclides of the uranium decay chain mainly due to the transport, the storage of raw materials and the free release of phosphogypsum waste. © 2013 Elsevier Ltd. Source

Andrefouet S.,Institute Of Recherche Pour Le Developpement | Menou J.-L.,Institute Of Recherche Pour Le Developpement | Naeem S.,Marine Research Center
Atoll Research Bulletin

In order to guide conservation efforts in Baa Atoll in the Republic of Maldives, macro-invertebrate species (principally sponges, sea stars, urchins, holothurians, crinoids, ophiuroids, ascidians, bivalves, gastropods, anemones, zooanthids, anthipatharian, gorgonians, alcyonaceans, and flatworms) were inventoried on 21 sites to provide an index of benthic species richness (number of species). A total of 182 species were recorded and identified. Richness ranged between 6 to 40 species per sampling sites. The richest sites were hard-bottom submerged lagoonal patch reefs experiencing high currents. Ecological rarity dominates the macro-invertebrate community pattern with 95 species found in only one sampling site. This new data set brings fresh knowledge on Baa Atoll and Maldives in order to identify biodiversity hot-spots. Further work will investigate the sensitivity of biodiversity conservation planning and sitting algorithms to this data set. Source

Puttonen I.,Abo Akademi University | Mattila J.,Abo Akademi University | Jonsson P.,University of Stockholm | Karlsson O.M.,IVL Swedish Environmental Reserach Institute Ltd | And 5 more authors.
Estuarine, Coastal and Shelf Science

Phosphorus contents in the sediments were determined in archipelago areas of the northern Baltic Sea (Svealand in Sweden and Åland, SW Finland and W Uusimaa in Finland) during 2008-2012. Spatial and vertical distribution of phosphorus was studied by analysing sediment samples from 345 stations of different seabed substrate types. A sequential extraction method was applied to evaluate the pool of the potentially mobile phosphorus, i.e., the amount of phosphorus that can be expected to be released from sediments to water with time, and possibly support primary production. In addition, vertical distribution of immobile phosphorus forms in the sediments was used as a tool to assess phosphorus burial. The uppermost 2cm of sediments were calculated to contain 126,000tonnes of phosphorus in the study area covering 19,200km2 of the seafloor. Subtracting the assumed average background content (i.e. that assumed to be buried) of this total phosphorus content gave an estimation of 31,000-37,000tonnes of potentially mobile phosphorus at the sediment surface. Redox sensitive iron-bound phosphorus accounts for two thirds of this pool. Compared with the total phosphorus input from the catchment of the entire Baltic Sea - 29,000 tonnes in 2009 - it can be concluded that the store of phosphorus that can be released with time from the sediments is large, and that internal phosphorus recycling processes thus may play a key role in phosphorus fluxes in the coastal zone. Spreading of hypoxia in the future, as recent modelling and sediment proxy results suggest, is likely to severely deteriorate the water quality, particularly in the archipelago areas where the water exchange is slow. © 2014 Elsevier Ltd. Source

Bigot L.,University of Reunion Island | Amir H.,Marine Research Center
Atoll Research Bulletin

A survey of scleractinian corals for 21 stations in Baa Atoll (Republic of Maldives) was conducted in June 2009. The goal of the survey was to i) compile for the first time for this atoll a scleractinian coral check-list, ii) estimate the atoll total richness, iii) estimate intra-atoll richness variation and iv) describe preliminary patterns of community structure according to geomorphology and location criteria. The survey was stratified by the main reef geomorphological units. A total of 173 species of scleractinia belonging to 49 genera were recorded, including several species new to Maldives. Conversely, a number of species of genera quite common in the Indian Ocean were absent of the list of Pocilloporidae. Average richness per station was nearly 60 species. Richness ratio between slopes and flats/tops were between 3 and 1.3, with an average of 2.1, highlighting richer slopes than flats and tops. Differences of community composition between geomorphologic strata and between oceanic/lagoonal reefs were significant. Central lagoonal reefs provided highest richness, and highest coral cover as well. These findings are critical to plan for the conservation of Baa Atoll biodiversity. Source

Barnes R.S.K.,University of Cambridge | Barnes R.S.K.,Marine Research Center

A preliminary attempt was made to quantify the alpha diversity of fiddler crabs (Uca spp.) along a short transect across the interface between an intertidal mudflat and a largely Avicennia mangrove at Ambeua on the Indonesian island of Kaledupa in Sulawesi Tenggara, by means of visual counts within 2 m2 quadrats. An astounding diversity of up to six seemingly coexisting species per quadrat-and a total of seven such species within an area of 4 m2-was revealed. Four species of the ecologically equivalent sentinel crabs (Macrophthalmus) were also present in the quadrats. Seven fiddler crab species equates to more than half those known from Wallacea, more than one-third of all those known from Indonesia, and almost one-fifth of the entire Uca fauna of the Indo-West-Pacific. © Springer Science+Business Media B.V. 2009. Source

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