References of "Sossey Alaoui, Khadija"
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See detailMacrophytes: Limitations of Using Them to Assess Reservoir Status According to the Water Framework Directive
Sossey Alaoui, Khadija ULg; Galoux, Daniel; Rosillon, Francis ULg

in International Journal of Water Sciences (2013)

Macrophytes are among the major groups of organisms that the Water Framework Directive (WFD) recommends should be used in assessing the status of natural lakes. The use of macrophytes in reservoir ... [more ▼]

Macrophytes are among the major groups of organisms that the Water Framework Directive (WFD) recommends should be used in assessing the status of natural lakes. The use of macrophytes in reservoir monitoring is still limited and further studies are needed on their inter-calibration and sources of variation. Many status assessment methods based on macrophyte <br />communities have been defined for lakes. Nevertheless, few of them have been tested for reservoirs. The purpose of the study is to highlight the limitations of using macrophytes to assess reservoir status according to the Water Framework Directive. <br />An assessment of macrophyte composition and abundance and of water quality was carried out in nine Walloon reservoirs between 2010 and 2012. The main limitations of the macrophyte approach for assessing these reservoirs were: i) geographical features; ii) physical variables; iii) lack of ecological information on the various macrophytic groups, such as helophytes, algae and mosses. We used two assessment methods to test the relevance of using macrophyte communities to assess reservoir status: the Flanders (Belgium) method (BE-FL method) and the United Kingdom method (UK method). The relationships between macrophyte metrics for both methods and nutrient enrichment were examined. Highly significant correlations were found between the chemical variables O-P [mg P/l]), Total P (µg P/l), Conductivity (µS/cm) and the trophic UK-metric (Lake Macrophyte Nutrient) (LMNI), as well as between such variables and the abundance of Bl-FL "disturbance indicators" metric(V). The UK "group of macrophyte species" metric provided limited information on the quality or degrees of degradation in the environment from which the sample was taken. [less ▲]

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Peer Reviewed
See detailMacrophytes : limitations of using them to assess reservoir status according to the water framework directive
Sossey Alaoui, Khadija ULg; Rosillon, Francis ULg

Conference (2013, July)

Macrophytes are among the major groups of organisms that the Water Framework Directive (WFD) recommends should be used in assessing the status of reservoirs. The use of macrophytes in reservoir monitoring ... [more ▼]

Macrophytes are among the major groups of organisms that the Water Framework Directive (WFD) recommends should be used in assessing the status of reservoirs. The use of macrophytes in reservoir monitoring is still fairly limited and studies are needed on their inter-calibration and sources of variation. Many status assessment methods based on macrophyte communities have been defined for lakes, Nevertheless few of them have been tested for reservoirs. The purpose of the study is to highlight the limitations of using macrophytes to assess reservoir status according to the Water Framework Directive. An assessment of macrophyte composition and abundance and of water quality was carried out in seven Walloon reservoirs between 2010 and 2012. The main limitations of the macrophyte approach for assessing these reservoirs were: i) geographical features, ii) physical variables, iii) water chemistry and iiii) lack of ecological information on the various macrophytic groups, such as helophytes, algae and mosses. Few of the taxa occurring in the Walloon reservoirs have an indicator score for status assessment based on macrophyte communities. We used two assessment methods to test the relevance of using macrophyte communities to assess reservoir status: the Flanders (Belgium) method (BE-FL method) and the United Kingdom method (UK-method). The relationships between macrophyte metrics for both methods and nutrient enrichment were examined. Highly significant correlations were found between the chemical variables (O-P [mg P/l]); P tot (μg P/l); total hardness (°F), conductivity (μS/cm) and the trophic UK-metric (LMNI); and between it and the abundance of ‘Bl-FL disturbance indicators’ metric (V). The ‘UK group of macrophyte species’ metric does not provide direct information on the quality or degree of degradation of the environment from which the sample was taken. [less ▲]

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See detailLes macrophytes dans les ruisseaux de référence wallons: caractérisation des sites et typologie floristique
Sossey Alaoui, Khadija ULg; Galoux, Daniel; Rosillon, Francis ULg

in Colloque international des Macrophytyes: IRSTEA, Bordeaux 28-30 mai 2013 (2013, May 30)

La Directive européenne cadre 2000/60/CE sur l’eau a pour objectif l’atteinte du bon état écologique et du bon état chimique au sein des bassins hydrographiques, d'ici 2015. Pour établir l’état écologique ... [more ▼]

La Directive européenne cadre 2000/60/CE sur l’eau a pour objectif l’atteinte du bon état écologique et du bon état chimique au sein des bassins hydrographiques, d'ici 2015. Pour établir l’état écologique, la Directive impose de mesurer l’écart à la référence pour les indicateurs de la qualité biologique des cours d’eau (macroinvertébrés, diatomées, poissons, macrophytes et phytoplancton). L’élaboration d’une typologie macrophytique des ruisseaux de référence du bassin hydrographique de la Meuse, en Wallonie est l’objectif de l’étude. Les 50 sites étudiés font l’objet d’une caractérisation physico-chimique et mésologique et ensuite de relevés de végétation. Ceux-ci sont effectués sur des segments de cours d’eau de 100m de long et le recouvrement de chaque espèce est estimé selon une échelle d’abondance. Les ruisseaux étudiés peuvent être considérés comme le résultat d’un inventaire quasi exhaustif pour la Wallonie. Les plantes supérieures (hydrophytes), les mousses, les hépatiques, les macroalgues sont identifiées sur le terrain et au laboratoire à l’aide du binoculaire et du microscope. Le degré de la pente, l’altitude de la source et du site, l’occupation du sol, la géologie et certaines caractéristiques physico-chimiques de l’eau (ph, conductivité, teneur en calcium, magnésium et alcalinité) permettent de caractériser les stations. Six ensembles de ruisseaux avec leurs espèces caractéristiques sont mis en évidence par le "Two-Way Clustering" et "l’Indicator Species". L'analyse du déterminisme de distribution de la végétation dans les différents ensembles montre que ces derniers sont étroitement liés aux régions naturelles et leur typologie s’inscrit dans la typologie physique choisie par le Service public de Wallonie. [less ▲]

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See detailMacrophytes: limitations of using them to assess reservoir status according to the Water Framework Directive
Sossey Alaoui, Khadija ULg; Galoux, Daniel; Rosillon, Francis ULg

in Peer Review (2013)

Macrophytes are among the major groups of organisms that the Water Framework Directive (WFD) recommends should be used in assessing the status of natural Lakes. The use of macrophytes in reservoir ... [more ▼]

Macrophytes are among the major groups of organisms that the Water Framework Directive (WFD) recommends should be used in assessing the status of natural Lakes. The use of macrophytes in reservoir monitoring is still fairly limited and studies are needed on their inter-calibration and sources of variation. Many status assessment methods based on macrophyte communities have been defined for lakes, Nevertheless few of them have been tested for reservoirs. The purpose of the study is to highlight the limitations of using macrophytes to assess reservoir status according to the Water Framework Directive. An assessment of macrophyte composition and abundance and of water quality was carried out in nine Walloon reservoirs between 2010 and 2012. The main limitations of the macrophyte approach for assessing these reservoirs were: i) geographical features, ii) physical variables and iii) lack of ecological information on the various macrophytic groups, such as helophytes, algae and mosses. We used two assessment methods to test the relevance of using macrophyte communities to assess reservoir status: the Flanders (Belgium) method (BE-FL method) and the United Kingdom method (UK-method). The relationships between macrophyte metrics for both methods and nutrient enrichment were examined. Highly significant correlations were found between the chemical variables (O-P [mg P/l]); Total P (µg P/l); Conductivity (µS/cm) and the trophic UK-metric (Lake Macrophyte Nutrient) (LMNI); and between it and the abundance of Bl-FL "disturbance indicators’ metric (V). The UK "group of macrophyte species’ metric provide a limited information's on the quality or degree of degradation of the environment from which the sample was taken. [less ▲]

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See detailMacrophytic Distribution and Trophic State of Some Natural and Impacted Watercourses - Belgium Wallonia
Sossey Alaoui, Khadija ULg; Rosillon, Francis ULg

in International Journal of Water Sciences (2013), 2(3), 1-11

In the present paper we investigated macrophyte community structure in 60 natural and impacted stream and river sites distributed throughout the Walloon river network. The objectives were to describe the ... [more ▼]

In the present paper we investigated macrophyte community structure in 60 natural and impacted stream and river sites distributed throughout the Walloon river network. The objectives were to describe the distribution of macrophyte assemblages in relation to physico‐chemical parameters of their environment and to assess the variability in ecological metrics within these watercourses. Two‐way clustering allowed us to simultaneously assign sample units and species to groups by performing two separate cluster analyses. Indicator species analysis allowed us to assess the degree to which a species indicated a group, based on its constancy and distribution of abundance. Six end‐groups were identified as a result of using twoway clustering and indicator species analysis techniques. Hygroamblystegium fluviatile, Chiloscyphus polyanthos and Lemanea fluviatilis were found to characterize acidic and low impacted streams and rivers (G1), while Ranunculus fluitans was found in all low impacted large streams (G2). Potamogeton pectinatus, proved to be more common in eutrophicated waters in the calcareous areas particularly in the ʺLoess low plateauxʺ region (G6). Cinclidotus riparius, Fissidens crassipes and Pellia endiviifolia, appeared in rivers situated in the Condroz region (G4), which was characterized by a high concentration of nitrogen. [less ▲]

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See detailAre ecological indices based on macrophytes communities pertinent tools to monitor ecological potential of Walloon reservoirs?
Sossey Alaoui, Khadija ULg; Galoux Daniel, SPW; Rosillon, Francis ULg

Poster (2012, June 19)

Diversity and trophic metrics based on macrophyte communities were calculated to test their pertinence to assess the ecological potential of Walloon reservoirs (Belgium). The BE-FL method (four ... [more ▼]

Diversity and trophic metrics based on macrophyte communities were calculated to test their pertinence to assess the ecological potential of Walloon reservoirs (Belgium). The BE-FL method (four complementary metrics) and the United Kingdom method (five metrics calculated using information on taxonomic composition and abundance of macrophyte species and groups of such species) were tested. Highly significant correlations were found between the chemical variables (o-P (mg P/l); P tot (µg P/l); NH4+ (mg N/l) DCO (mg/l) Cond (µS/cm), the phytoplankton assemblage index, Q (Padisak et al., 2006) applied for the same reservoirs (Descy et al., 2010). and trophic metric LMNI and between them and the abundance of disturbance indicators (V). Groupe of macrfophyte species metrics do not necessarily provide any direct information on the quality or degree of degradation of the environment from which the sample was taken, whereas trophic indices do. [less ▲]

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See detailThe contribution of macroalgae to the assessment of the ecological quality of the rivers in Wallonia based on macrophytes indicator values in the British and French approaches
Sossey Alaoui, Khadija ULg; Galoux, Daniel; Rosillon, Francis ULg

Poster (2009, November 26)

In accordance with the water Framework Directive (WFD, European Parliament & The Council of the European Union, 2000) defining the overall ecological status of rivers, many hundred sites were analysed in ... [more ▼]

In accordance with the water Framework Directive (WFD, European Parliament & The Council of the European Union, 2000) defining the overall ecological status of rivers, many hundred sites were analysed in the Walloon network. Within each sample, macroalgae data were gathered at species/or at genus level and the main water quality parameters were collected several times per year from 2005 to 2009. <br />Seventeen species and genera cited in the French and English lists of macrophyte methods used to assess the ecological quality of rivers were considered. Within these sites, the ratio of the macroalgae among the contributory species was examined and the impact of these on the final scores of the River Macrophytes Nutrient index (United Kingdom, Wilby et al.,2006) and the biological macrophytic index in rivers (France, Haury et al., 2006) was analysed.At the same time, a ranking of these macroalgae along a trophy gradient has been established thanks to a principal component analysis of the physico-chemical parameters and a weighting of the species presence in a given waterbody by its abundance.The relationships between macroalgae scores and those found in France and in United Kingdom were studied using the Spearman rank correlation coefficient. <br />Literature: <br />European Parliament & The Council of the European Union, 2000. Directive 2000/60/EC of the European Parliament and of the Council establishing a framework for the Community action in the field of water policy. Official Journal of the European Communities 327: 1-72.Haury, J., M.-C. Peltre, M. Trémolières, J. Barbe, G. Thiébaut, I. Bernez, H. Daniel, P. Chatenet, G. Haan-Archipof, S. Muller, A. Dutartre, C. Laplace-Treyture, A. Cazaubon & E. Lambert-Servien, 2006. A new method to assess water trophy and organic pollution – the Macrophyte Biological Index for Rivers (IBMR): its application to different types of river and pollution. Hydrobiologia 570: 153-158. Willby, N., J. Pitt & G. Phillips, 2006. Summary of approach used in LEAFPACS for defining ecological quality of rivers and lakes using macrophyte composition. Draft Report January 2006. [less ▲]

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See detailMacrophyte biological index for rivers (MBIR) application for an ecological assessment of walloon rivers, prelilminary investigations.
Sossey Alaoui, Khadija ULg; Galoux, D.; Rosillon, Françis ULg

Conference (2009)

Samples were collected from 45 sites along the Walloon river network in 2007, in accordance with the Water Framework Directive (WFD, European Union, 2000), used to define the overall ecological status of ... [more ▼]

Samples were collected from 45 sites along the Walloon river network in 2007, in accordance with the Water Framework Directive (WFD, European Union, 2000), used to define the overall ecological status of rivers. Within each collected sample, macrophyte data were gathered at species level and the main water quality parameters were analyzed. This involved the use of two approaches: firstly, methods of ordination and classification (Principal Component Analysis and Multiple Factorial Analysis) and secondly, aquatic macrophyte community indexes. The Macrophyte Biological Index for Rivers (MBIR) was used to define the ecological status of the macrophyte community in response to eutrophication pressure. Four trophic qualities were detected in all the monitored stations: 56% of the sites showed a good trophic quality, with the Ardennes region in the leading position and only 2% of the sites showed a poor trophic quality. A Multiple Factorial Analysis (MFA) made it possible to regroup the species according to their ecological affinities and to specify their indicator values in relation to some abiotic parameters. As a result, a rivers typology was outlined based on this analysis. The dendrogram of the Hierarchical Cluster Analysis (HCA) gave three clusters determined by active variables of each compartment that defined functional parts of the Walloon network: Chiloscyphus polyanthos (L.) Corda, Rhynchostegium riparioides(Hedw.)C.Jens., Fontinalis squamosa(Hedw) and Ranunculus penicillatus (Dum.)Bb. showed an oligotrophic status and low mineralization in the Ardennes (GI), while P. pectinatus(Linne), Cladophora glomerata(Linnaeus)proved to be found more often in eutrophicated waters in the Region limoneuse (GIII). Pellia endvifolia (Dicks.)Dum, Fissidens crassipes(Br.Eur);Cinclidotus riparius (Web. & Mohr.) appeared in the Condroz and Famenne, rivers characterized by a high concentration of nitrogen (N-35. NO3-) (GII). [less ▲]

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See detailContribution méthodologique à l'évaluation de la qualité des eaux des revières à l'aide des macrophytes aquatiques(spermatophytes et bryophytes) - Application au réseau hydrographique luxembourgeois-
Sossey Alaoui, Khadija ULg

Doctoral thesis (2006)

La répartition des Macrophytes aquatiques (Phanérogames et Bryophytes) a été étudiée sur l’ensemble des cours d’eau luxembourgeois. Des prospections macrophytiques ont été réalisées pour 340 stations ... [more ▼]

La répartition des Macrophytes aquatiques (Phanérogames et Bryophytes) a été étudiée sur l’ensemble des cours d’eau luxembourgeois. Des prospections macrophytiques ont été réalisées pour 340 stations entre 2000 et 2003. Dans chacune d’entre elles, des paramètres mésologiques ont été mesurés et des analyses physico-chimiques des eaux ont été effectuées dans 63% des stations. La relation macrophytes-habitat a été envisagée selon deux approches : multidimensionnelle d’une part et par des profils écologiques d’autre part. Les principales espèces aquatiques et semi-aquatiques des rivières luxembourgeoises ont été classées en différents groupes par une Analyse Factorielle Multiple (AFM) sur base des descripteurs physico-chimiques et morpho-métriques impliqués dans la dispersion, l’établissement et la persistance des espèces aquatiques. Basée sur l’abondance de ces groupements, une typologie floristique des cours d’eau a conduit à l’individualisation de différents groupes de stations : 1 les têtes de bassins ardennais caractérisées par Chiloscyphus pallescens et C. polyanthos ainsi que par un éclairement faible et un substrat grossier ; 2 les cours principaux de l’Oesling à Ranunculus penicillatus, R. peltatus ; 3 Berula erecta et Veronica beccabunga caractérisent les zones amonts du Gutland dont les eaux montrent des teneurs élevées en nitrates ; 4 les cours principaux lorrains dont les eaux sont plus minéralisés et riches en SO42- sont caractérisés par P. crispus, E. canadensis, P. natans et Z. palustris ; 5 et finalement les zones fortement eutrophisées (rithrons) caractérisées par un grand nombre d’espèces (Potamogeton pectinatus, P. perfoliatus, Sparganium emersum….) et par des critères morpho-métriques très importants (profondeur, éclairement, largeur et température). Des profils écologiques et des cartes de distributions des principales espèces rencontrées (Phanérogames et Bryophytes) nous ont permis de délimiter leurs comportements vis a vis de l’eutrophisation et de la minéralisation. Les différences observées par rapport à la littérature témoignent d’une prolifération des espèces polluo-tolérantes d’une part et d’une pression anthropique importante le long du réseau hydrographique luxembourgeois d’autre part. Une méthode indicielle a été appliquée afin d’évaluer la qualité des rivières sur base des espèces inventoriées. Néanmoins, la faible occurrence des espèces et la non prise en compte des algues ont diminué l’acuité de la méthode. L’importance des formations végétales riveraines au seins des écosystèmes aquatiques et plus particulièrement dans le domaine de la bioindication a été étudiée également. Le pouvoir bioindicateur pour les facteurs acidité, azote, humidité, et lumière (ELLENBERG et al., 1992) a été précisé pour 220 espèces rivulaires inventoriées le long des sites de l’Oesling et du Gutland. Une typologie des biotopes riverains a été dégagée sur base de ces valeurs bioindicatrices. Le déterminisme de la richesse des sols riverains a été envisagé dans sa composante naturelle Oesling-Gutland, ainsi que dans sa composante anthropique. [less ▲]

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