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Alouache S.,University of Science and Technology Houari Boumediene | Alouache S.,National School of Marine Science and Coastal Planning | Kada M.,National School of Marine Science and Coastal Planning | Messai Y.,University of Science and Technology Houari Boumediene | And 3 more authors.
Microbes and Environments | Year: 2011

The aim of the study was to evaluate bacterial antibiotic resistance in seawater from four beaches in Algiers. The most significant resistance rates were observed for amoxicillin and ticarcillin, whereas they were relatively low for ceftazidime, cefotaxime and imipenem. According to sampling sites, the highest resistance rates were recorded for 2 sites subjected to chemical and microbiological inputs (amoxicillin, 43% and 52%; ticarcillin, 19.6% and 47.7%), and for 2 sites relatively preserved from anthropogenic influence, resistance rates were lowest (amoxicillin, 1.5% and 16%; ticarcillin, 0.8% and 2.6%). Thirty-four bacteria resistant to imipenem (n=14) or cefotaxime (n=20) were identified as Pseudomonas aeruginosa (n=15), Pseudomonas fluorescens (7), Stenotrophomonas maltophilia (4), Burkholderia cepacia (2), Bordetella sp. (1), Pantoea sp. (1), Acinetobacter baumannii (1), Chryseomonas luteola (1), Ochrobactrum anthropi (1) and Escherichia coli (1). Screening for extended spectrum β-lactamase showed the presence of CTX-M-15 β-lactamase in the E. coli isolate, and the encoding gene was transferable in association with the IncI1 plasmid of about 50 kbp. Insertion sequence ISEcp1B was located upstream of the CTX-M-15 gene. This work showed a significant level of resistance to antibiotics, mainly among environmental saprophytic bacteria. Transmissible CTX-M-15 was detected in E. coli; this may mean that contamination of the environment by resistant bacteria may cause the spread of resistance genes.

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.

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.

Guendouzi Y.,University of Mostaganem | Ghalmi R.,National School of Marine Science and Coastal Planning | Boudjellal M.,National School of Marine Science and Coastal Planning | El Morhit M.,Mohammed V University
Journal of Materials and Environmental Science | Year: 2015

This study is a contribution to the assessment of water quality of the Algiers Bay in terms of chemical pollution. Metallic trace elements (Mercury, Lead and Zinc) were identified using the atomic absorption spectrophotometry on samples taken in the Posidonia ecosystem (sediment, Posidonia oceanica and Paracentrotus lividus). Samples come from two stations located in the extreme East and West of the Algiers Bay (Algiers beach and Rais Hamidou). Results of atomic absorption spectrophotometry showed that the site Rais Hamidou is most contaminated by the MTE website Algiers beach. In addition, the zinc is the most bioaccumulated in three MTE studied, and species (P. lividus) is the most bioaccumulatrice of the three compartments of the ecosystem studied.

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.

Dauvin J.C.,University of Caen Lower Normandy | Alizier S.,Lille University of Science and Technology | Rolet C.,Lille University of Science and Technology | Bakalem A.,Montpellier SupAgro | And 5 more authors.
Ecological Indicators | Year: 2012

The interest in benthic indicators for soft-bottom marine communities has dramatically increased after a rather long period of relative stagnation due to the need for new tools to assess the status of marine waters, called for by the Clean Water Act and the Water Framework Directive. Our expertise on benthic communities has permitted us to gather a vast amount of data from diverse water bodies under unpolluted and polluted conditions (e.g.; accidental oil spill, sewage, long-term anthropogenic estuarine constraints) in tidal estuaries, harbours, and on the coastal shelf from Atlantic Ocean and Mediterranean Sea. We compared the results of four biotic indices on the various available datasets: Shannon-Wiener H′ diversity, AMBI and BO2A, which divide the species into Ecological Groups, and ITI, which divides the species into trophic groups, and the agreement of Best Professional Judgement (BPJ) on the assessment of ecological conditions. Benthic indicators as "sentinel species", which is a particular species that by its presence or its relative abundance warns of possible unbalances in the surrounding environment or distortions in community functions, was also tested. Indicators, BPJ and opportunist sentinel species gave similar ECoQS for the different sampling sites. We discuss the use of Biological Indicators as 'objective' or 'subjective' alternatives for assessing soft-bottom communities, and propose to employ simple methods such as BPJ and taxonomy sufficiency in such diagnostic approaches. © 2011 Elsevier Ltd.

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.

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.

Boumaza S.,National School of Marine Science and Coastal Planning | Boudefoua N.,National School of Marine Science and Coastal Planning | Boumaza R.,Agrocampus Ouest | Semroud R.,National School of Marine Science and Coastal Planning
Journal of Experimental Marine Biology and Ecology | Year: 2014

In the Mediterranean, the discharge of urban effluents in coastal areas adversely affects Posidonia oceanica, since it induces nutrient enrichment and a decrease of water clarity, but data from the southern Mediterranean are very sparse. In this paper we examine the differences in P. oceanica parameters from a disturbed site (Bou Ismaïl) and a reference site (Kouali), at meadow level (shoot density, meadow cover), at individual level (leaf biometry, A coefficient, epiphytic index) and at biochemical level (total phenols). The differences were examined at the upper limit (- 5. m) and the lower limit (- 20 m), during an annual cycle. Results indicated a significantly lower mean meadow cover at the upper limits of the disturbed site compared to the reference site. The leaf length and leaf area were also lower at the disturbed site, and this difference was recorded all year round at the upper limit. The epiphytic index and the A coefficient of adult leaves were higher only in July and October at the upper limits of the disturbed site. In contrast, total phenol concentration of the leaves did not show any response to disturbances related to urban effluents. However, the biosynthesis of phenolic substances at the two sites was significantly higher in the intermediate leaves, in winter, when growth slows down. The unexpected higher value of total phenol concentration recorded in the intermediate leaves and sheaths in spring at the reference site is discussed. © 2014 Elsevier B.V.

Amriche A.A.E.,Montpellier SupAgro | Guerfi M.,National School of Marine Science and Coastal Planning
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2012

Soil moisture (SM) is of fundamental importance to many agricultural, hydrological and climate studies. In this paper, a simple approach for mapping near-surface SM from Envisat ASAR data was developed. Four high-resolution images covering a semiarid region in Algeria were acquired with the same sensor configuration. We performed the pretreatment using the Basic Envisat SAR Toolbox of the European Space Agency. Then, we extracted the backscattering coefficient σ0 (dB) from the filtered and calibrated images. On the other hand, five training sites with different soil physical properties and vegetation cover were selected for monitoring SM. The field campaigns were conducted concurrent to satellite image acquisitions to measure soil water content in the top five centimeters using the gravimetric method. The study of linear regressions associated to the change detection approach allowed the expression of the backscattering coefficient as a function of volumetric soil moisture (σ0 = a*θ + b). The coefficients "a" and "b" of the equation slightly differ from one site to another and also from one season to the next. This difference is mainly due to the effects of surface roughness and vegetation biomass variations. Our study confirms a good agreement between the volumetric nearsurface SM and the radar backscattering coefficient for all the test fields. The comparison between measured and estimated SM proves the accuracy of the inversion models used here with a mean average error of less than 5%. At the end, high resolution maps of soil moisture distribution were obtained from the acquired radar images. © 2012 SPIE.

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