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Bakalem A.,Montpellier SupAgro | Dauvin J.-C.,Normandie University | Dauvin J.-C.,Laboratoire Morphodynamique Continentale et COtiere | Dauvin J.-C.,French National Center for Scientific Research | Grimes S.,National School of Marine Science and Coastal Planning
Journal of the Marine Biological Association of the United Kingdom | Year: 2014

Recent sampling surveys (2011-2012) of the shallow (0-50 m) hard-bottom communities and re-examination of some soft-bottom communities (5-143 m) along the Algerian coast have allowed the collection of 33 species (five Caprelloidea, 27 Gammaridea and one Hyperiidea), which were not recorded before in the inventory of the marine amphipod fauna of Algeria (Bakalem & Dauvin, 1995; Grimes et al., 2009). This paper reports the number of specimens sampled for each of these 33 species and provides data on their geographical distribution and habitats. Fourteen of the species (43%) are considered to be endemic to the Mediterranean Sea; 15 others are north-eastern Atlantic and Mediterranean species, and the four last are cosmopolitan species. Twenty-nine of the new records are known for Italian waters and 19 in Greek waters where there is intensive amphipod inventory. The total number of marine amphipod fauna in Algeria is now 332. Copyright © Marine Biological Association of the United Kingdom 2014.

Grimes S.,National School of Marine Science and Coastal Planning | Ruellet T.,CNRS Laboratory of Oceanology and Geosciences | Dauvin J.-C.,CNRS Laboratory of Oceanology and Geosciences | Boutiba Z.,Oran University of Science and Technology - Mohamed Boudiaf
Marine Pollution Bulletin | Year: 2010

Between 1995 and 2001, the soft-bottom communities along the 1180. km of the Algerian coast were sampled in nine gulfs and 12 harbours, providing a total of 655 samples. Eight macrozoobenthos-based biotic indices (S, N, H′, BQI, AMBI, BENTIX, BO2A and ITI) were selected to describe the general patterns of the coastal water quality status and to establish a quality diagnosis for the different zones subjected to anthropogenic pressure (e.g., harbour construction, industrial and urban pollution). Reference values were determined for each of the eight indices selected by analyzing the indices' parameter distribution. The Ecological Quality Ratio (EQR) was estimated for each index, resulting in an EQR Mean Score and an EQR Bad Score. From these EQR, we defined an EQS for each sample. The agreement between these EQS was analysed using the Kappa method in order to propose a survey strategy for the Algerian coastal waters that would take into account the soft-bottom biological compartment. The results clearly indicate that high and good quality assessments are prevalent in the gulfs, while quality assessments in harbours vary greatly from bad to good. The effect of pollution observed in the harbours can be classified in two main groups, according to when they were constructed and their relative degree of openness to the sea, which permits better water circulation and probably dilutes the pollution. © 2010 Elsevier Ltd.

Benkacem T.,Blida University | Hamdi B.,National School of Marine Science and Coastal Planning | Hamdi B.,University of Science and Technology Houari Boumediene | Chamayou A.,French National Center for Scientific Research | And 2 more authors.
Powder Technology | Year: 2016

Natural diatomite from Sig/Algeria was treated with 0.5, 1.0, 3.0 and 5.0 M nitric acid solutions for 2 h under reflux at 333 K in order to improve its performance as support of catalyst. The purified silica powders obtained from frustules can also be used to reinforce composites. The solids obtained were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray fluorescence (XRF), Fourier transform infrared (FTIR) spectroscopy, thermal analyses, and nitrogen adsorption-desorption at 77 K. Treatment of diatomite earth with nitric acid reduced mineral impurities, such as Fe2O3 and alkali metal oxides (CaO, MgO), eliminated carbonates and increased SiO2 ratio from 88% to 98%. The SEM micrographs showed the original geometry of the pores to be preserved. The surface properties were also evaluated using inverse gas chromatography at infinite dilution (IGC-ID) and finite concentration (IGC-FC). The interest here was to establish whether the technique is sufficiently sensitive to detect variations in the surface properties of the diatomite due to this chemical treatment. The IGC analysis permitted to reach several surface energy components with organic probes. Between them, the distribution function of the adsorption energy sites obtained with the isopropanol probe revealed a silica structure after the 5 M nitric acid treatment. © 2016 Elsevier B.V.

Dauvin J.-C.,University of Caen Lower Normandy | Dauvin J.-C.,French National Center for Scientific Research | Grimes S.,National School of Marine Science and Coastal Planning | Bakalem A.,Montpellier SupAgro
Journal of Natural History | Year: 2013

The Mediterranean Sea is known as a biodiversity hot spot, with 16,848 species reported. Biodiversity is higher in coastal areas and decreases with depth. However, knowledge about the southwestern sector remains scarce. For the last three decades, sampling of soft-bottom communities along the 1180 km of the shallow Algerian coast (0-136 m) has recorded 1642 macrobenthic species. There is a decreasing west-east species-richness gradient, especially for the total species richness and the amphipods. In addition, quantitative sampling in Bou Ismail Bay in summer 1988 (98 sampling sites for a total of 841 species) shows that diversity indices (i.e. species richness, >100 species for 0.2 m-2; Shannon diversity, >6.0; and ES50, >34) are among the highest for similar sand and muddy-fine sand communities in the Mediterranean Sea and the northeastern Atlantic Ocean. Bou Ismail Bay appears to have the highest species richness among Algerian bays, probably because of its variety of benthic habitats and the absence of significant pollution in this area. Monitoring must be undertaken to survey this high biodiversity, and a national strategy should be proposed to preserve high diversity zones. © 2013 Copyright Taylor and Francis Group, LLC.

Brigolin D.,University of Venice | Lourguioui H.,National School of Marine Science and Coastal Planning | Lourguioui H.,University of Science and Technology Houari Boumediene | Taji M.A.,ACRI EC | And 3 more authors.
Ocean and Coastal Management | Year: 2015

This paper presents a methodology for the selection of coastal sites for finfish cage farming, based on both satellite remotely sensed data and mathematical models. Such methodology can be applied, at screening level, also in areas where field data are lacking, and consists in two steps. In the first one, candidate areas are ranked according to criteria which take into account the risk of cage breaking due to wave actions and fish welfare requirements. This step involves the post-processing of satellite data and results of operational oceanographic models by means a multi-criteria methodology implemented in a GIS environment. In the second step, an integrated aquaculture impact assessment model is applied to the most suitable areas in order to obtain a preliminary assessment of the potential interaction of a newly established cage with benthic habitats. The methodology was applied to an Algerian coastal area near the town of Bejaia where the central government is planning to develop aquaculture activities. Results show that the procedure allows to perform a site selection, which combines the quality of a site from the aquaculture use perspective with the conservation of endangered benthic habitats (Posidonia oceanica meadows) under the spatial restrictions imposed by existing activities. This result goes in the direction of defining site selection methodologies complying with the principles of the ecosystem approach to aquaculture and providing a science-based support in the framework of the implementation of the UNEP/MAP ecological approach. © 2015 Elsevier Ltd.

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