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Auteur Ahmed Menad |
Documents disponibles écrits par cet auteur (3)
Affiner la recherche Interroger des sources externesEvaluation des impacts de l’irrigation par les eaux du barrage de BENI HAROUN sur les plantes et les sols de la région de Mila. / Sara Bouaroudj
Titre : Evaluation des impacts de l’irrigation par les eaux du barrage de BENI HAROUN sur les plantes et les sols de la région de Mila. Type de document : texte imprimé Auteurs : Sara Bouaroudj, Auteur ; Ahmed Menad, Directeur de thèse Mention d'édition : 29 / 09 / 2021 Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2021 Importance : 231 f. Format : 30 cm. Note générale : 1 copies imprimées disponibles
Langues : Français (fre) Catégories : Français - Anglais
BiologieTags : Biologie et Ecologie Végétale: Ecologie et Environnement barrage Béni Haroun irrigation sol métaux lourds salinisation Beni Haroun dam soil heavy metals salinization سد بني هارون ري تربة معادن ثقيلة تملح Index. décimale : 570 Sciences de la vie. Biologie Résumé : The Beni Haroun dam is a vital source of water for drinking and irrigation in the city of Mila, Algeria. In this study, an assessment of the quality of irrigation water and its impacts on the properties of irrigated soils was carried out, as well as an assessment of the contamination by heavy metals (Cd, Cu, Zn, Pb, Cr and Fe) of edible vegetables, tomato (Solanum lycopersicum), Melon (cucumis melo) and Lettuce (Lactuca sativa). To this end, sampling was conducted at eight water stations between May 2014 and April 2015 on a monthly basis. Soil samples were collected at 14 stations. 12 on irrigated soils, and 2 on non-irrigated control soil, seasonally at four depth levels (0.10, 20 and 30 cm). The results revealed that the chemical facies of the waters are chlorinated calcium magnesium sulphate with a low content of heavy metals, a pH between (6.5 and 8.4), excess chloride and bicarbonate. A high conductivity where (38.53%) of the samples are not recommended for irrigation, the Richard diagram shows four classes, 1) C3S1 (61.45%) average to poor quality, 2) C4S1 (30.2%) poor to bad, 3) C4S2 (5.2%) very bad and 4) C5S3 (3.12%) of water unfit for irrigation ,while
the Wilcox diagram showed that (58.33%) of the samples are of good quality and (41.66%) are not suitable for irrigation. Water is safe for irrigation based on quality indices: MH, IP, KR and RSC. For soils irrigation has increased their pH, EC, MO and total CaCO3, which is leached and accumulated in the deep layers, the metal contents in the irrigated soils have been found to be higher than the control soil but still below the recommended international limits, Fe is the most bioavailable element in soil with levels ranging from
97.24 to 936.39 µg/mg, Zn (11.9 and 497.8 µg/mg), Pb (27.30 and 40.40 µg/mg). However, Cr (0.92-2.26 µg/mg), Cu (0.20-0.51 µg/mg) and Cd (0.11-0.25 µg/mg) have very low bioavailability. Whereas according to the Factor of enrichment they are classified as follows: Zn>Cu> Cd> Cr> Fe >Pb, Consequently, these soils present a risk
of contamination during a long period of irrigation. Plant metal concentrations do not exceed standards, but Cd and Pb levels are higher than normal. The organ type factor influences the accumulation of metals, and
the roots of Tomato and Melon, and lettuce leaves are the organs accumulating the most metals, the highest Transfer Factors are those of: Cd (1 , 61) in lettuce leaves, Cu (1.48) in tomato and melon fruits, Cr (0.89) in lettuce leaves, the study indicates a potential ecological risk to plants which could result in risks to human health. The study concludes that strict protection measures and guidelines are needed to
minimize the negative impacts of irrigation by these waters in the study area.
Note de contenu :
Annexes.Diplôme : Doctorat en sciences En ligne : ../theses/biologie/BOU7804.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=11636 Evaluation des impacts de l’irrigation par les eaux du barrage de BENI HAROUN sur les plantes et les sols de la région de Mila. [texte imprimé] / Sara Bouaroudj, Auteur ; Ahmed Menad, Directeur de thèse . - 29 / 09 / 2021 . - جامعة الإخوة منتوري قسنطينة, 2021 . - 231 f. ; 30 cm.
1 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
BiologieTags : Biologie et Ecologie Végétale: Ecologie et Environnement barrage Béni Haroun irrigation sol métaux lourds salinisation Beni Haroun dam soil heavy metals salinization سد بني هارون ري تربة معادن ثقيلة تملح Index. décimale : 570 Sciences de la vie. Biologie Résumé : The Beni Haroun dam is a vital source of water for drinking and irrigation in the city of Mila, Algeria. In this study, an assessment of the quality of irrigation water and its impacts on the properties of irrigated soils was carried out, as well as an assessment of the contamination by heavy metals (Cd, Cu, Zn, Pb, Cr and Fe) of edible vegetables, tomato (Solanum lycopersicum), Melon (cucumis melo) and Lettuce (Lactuca sativa). To this end, sampling was conducted at eight water stations between May 2014 and April 2015 on a monthly basis. Soil samples were collected at 14 stations. 12 on irrigated soils, and 2 on non-irrigated control soil, seasonally at four depth levels (0.10, 20 and 30 cm). The results revealed that the chemical facies of the waters are chlorinated calcium magnesium sulphate with a low content of heavy metals, a pH between (6.5 and 8.4), excess chloride and bicarbonate. A high conductivity where (38.53%) of the samples are not recommended for irrigation, the Richard diagram shows four classes, 1) C3S1 (61.45%) average to poor quality, 2) C4S1 (30.2%) poor to bad, 3) C4S2 (5.2%) very bad and 4) C5S3 (3.12%) of water unfit for irrigation ,while
the Wilcox diagram showed that (58.33%) of the samples are of good quality and (41.66%) are not suitable for irrigation. Water is safe for irrigation based on quality indices: MH, IP, KR and RSC. For soils irrigation has increased their pH, EC, MO and total CaCO3, which is leached and accumulated in the deep layers, the metal contents in the irrigated soils have been found to be higher than the control soil but still below the recommended international limits, Fe is the most bioavailable element in soil with levels ranging from
97.24 to 936.39 µg/mg, Zn (11.9 and 497.8 µg/mg), Pb (27.30 and 40.40 µg/mg). However, Cr (0.92-2.26 µg/mg), Cu (0.20-0.51 µg/mg) and Cd (0.11-0.25 µg/mg) have very low bioavailability. Whereas according to the Factor of enrichment they are classified as follows: Zn>Cu> Cd> Cr> Fe >Pb, Consequently, these soils present a risk
of contamination during a long period of irrigation. Plant metal concentrations do not exceed standards, but Cd and Pb levels are higher than normal. The organ type factor influences the accumulation of metals, and
the roots of Tomato and Melon, and lettuce leaves are the organs accumulating the most metals, the highest Transfer Factors are those of: Cd (1 , 61) in lettuce leaves, Cu (1.48) in tomato and melon fruits, Cr (0.89) in lettuce leaves, the study indicates a potential ecological risk to plants which could result in risks to human health. The study concludes that strict protection measures and guidelines are needed to
minimize the negative impacts of irrigation by these waters in the study area.
Note de contenu :
Annexes.Diplôme : Doctorat en sciences En ligne : ../theses/biologie/BOU7804.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=11636 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité BOU/7804 BOU/7804 Thèse Bibliothèque principale Thèses Disponible
Titre : Evaluation des indicateurs de la désertification dans les écosystèmes steppiques : cas de la région du Hodna (Msila) Type de document : texte imprimé Auteurs : Saifi Merdas, Auteur ; Ahmed Menad, Auteur Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2017 Importance : 119 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles
Langues : Français (fre) Catégories : Français - Anglais
BiologieTags : Dégradation des terres steppe aride méditerranéenne l'activité de pâturage diversité de
la communauté végétale structure de la communauté végétale échelle spatiale diversité bêta la
détection des changements Land degradation arid Mediterranean steppe grazing activity plant community
diversity plant community structure spatial scale beta diversity change detection.Index. décimale : 570 Sciences de la vie. Biologie Résumé : This study examines the effects of livestock grazing on plant communities of arid steppe ecosystems,
in central steppe rangelands of Algeria, Hodna basin. In addition, how land use changes over the past
30 years.Desertification is a worldwide concern; in Algeria, land degradation threats more than 20
million hectares of steppe rangelands. Overgrazing can generate a regressive chain reaction leading to
degradation of vegetation cover and loss of biodiversity. The use of indicators to assess desertification
is suitable to detect the state of the health of rangeland ecosystems.
We conducted a comparative study of the plant community structure and diversity in grazed and
ungrazed areas. We compared alpha and beta diversities using the Hill Index between the two
treatments, and used the additive partitioning of beta diversity to test whether the difference in plant
species composition is due to species spatial turnover or nestedness. Besides, by using the
multiplicative diversity partitioning, we examined the effects of grazing on beta diversity at two
spatial scales (i.e. among-transects, and among-sites). In addition, we assessed soil surface conditions;
vegetation, litter, bare ground, biological soil crusts and Stipa tenacissima cover. For change detection,
we used diachronic study by comparing land cover of three years 1984, 2000 and 2014.
For alpha diversity, grazing reduced significantly the diversity of the annual species; however,
perennials were not affected significantly. The results revealed a significant compositional difference
between grazed and ungrazed areas. Essentially, the additive partitioning of beta diversity indicated
that ~74% of the overall beta diversity was due to species turnover and ~26% was due to nestedness.
The analysis of beta diversity at different spatial scales showed that grazing increased beta diversity at
small scales and decreased beta diversity at coarse scales (among-sites). In addition, grazing activities
have largely reduced values of the vegetation cover and diversity in grazed areas. The cover of the
most dominant species (Stipa tenacissima), was not affected by grazing. The high value of bare
ground cover indicated regressive trend, this can be interpreted as a process of desertification.
Nevertheless, the protection from grazing increased significantly the species diversity of annual
species and vegetation cover. Land cover changed regressively from 1984 to 2014.
These results suggest that grazing changes the composition of plant community and affects mainly the
annual plants. Furthermore, grazing increases both compositional variation at small spatial scales and
vegetation homogeneity at coarse spatial scales. This study highlights the importance of protection and
conservation as an effective management tool for maintaining the plant community structure and
diversity in threatened ecosystems. It is recommended to use controlled grazing and increase the
number of protected areas.
Diplôme : Doctorat en sciences En ligne : ../theses/biologie/MER7132.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=10470 Evaluation des indicateurs de la désertification dans les écosystèmes steppiques : cas de la région du Hodna (Msila) [texte imprimé] / Saifi Merdas, Auteur ; Ahmed Menad, Auteur . - جامعة الإخوة منتوري قسنطينة, 2017 . - 119 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
BiologieTags : Dégradation des terres steppe aride méditerranéenne l'activité de pâturage diversité de
la communauté végétale structure de la communauté végétale échelle spatiale diversité bêta la
détection des changements Land degradation arid Mediterranean steppe grazing activity plant community
diversity plant community structure spatial scale beta diversity change detection.Index. décimale : 570 Sciences de la vie. Biologie Résumé : This study examines the effects of livestock grazing on plant communities of arid steppe ecosystems,
in central steppe rangelands of Algeria, Hodna basin. In addition, how land use changes over the past
30 years.Desertification is a worldwide concern; in Algeria, land degradation threats more than 20
million hectares of steppe rangelands. Overgrazing can generate a regressive chain reaction leading to
degradation of vegetation cover and loss of biodiversity. The use of indicators to assess desertification
is suitable to detect the state of the health of rangeland ecosystems.
We conducted a comparative study of the plant community structure and diversity in grazed and
ungrazed areas. We compared alpha and beta diversities using the Hill Index between the two
treatments, and used the additive partitioning of beta diversity to test whether the difference in plant
species composition is due to species spatial turnover or nestedness. Besides, by using the
multiplicative diversity partitioning, we examined the effects of grazing on beta diversity at two
spatial scales (i.e. among-transects, and among-sites). In addition, we assessed soil surface conditions;
vegetation, litter, bare ground, biological soil crusts and Stipa tenacissima cover. For change detection,
we used diachronic study by comparing land cover of three years 1984, 2000 and 2014.
For alpha diversity, grazing reduced significantly the diversity of the annual species; however,
perennials were not affected significantly. The results revealed a significant compositional difference
between grazed and ungrazed areas. Essentially, the additive partitioning of beta diversity indicated
that ~74% of the overall beta diversity was due to species turnover and ~26% was due to nestedness.
The analysis of beta diversity at different spatial scales showed that grazing increased beta diversity at
small scales and decreased beta diversity at coarse scales (among-sites). In addition, grazing activities
have largely reduced values of the vegetation cover and diversity in grazed areas. The cover of the
most dominant species (Stipa tenacissima), was not affected by grazing. The high value of bare
ground cover indicated regressive trend, this can be interpreted as a process of desertification.
Nevertheless, the protection from grazing increased significantly the species diversity of annual
species and vegetation cover. Land cover changed regressively from 1984 to 2014.
These results suggest that grazing changes the composition of plant community and affects mainly the
annual plants. Furthermore, grazing increases both compositional variation at small spatial scales and
vegetation homogeneity at coarse spatial scales. This study highlights the importance of protection and
conservation as an effective management tool for maintaining the plant community structure and
diversity in threatened ecosystems. It is recommended to use controlled grazing and increase the
number of protected areas.
Diplôme : Doctorat en sciences En ligne : ../theses/biologie/MER7132.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=10470 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité MER/7132 MER/7132 Thèse Bibliothèque principale Thèses Disponible
Titre : Potentiel antioxydant des algues des côtes de l’est Algérien. Type de document : texte imprimé Auteurs : Hichem Mezdour, Auteur ; Ahmed Menad, Directeur de thèse Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2018 Importance : 119 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles
Langues : Français (fre) Catégories : Français - Anglais
BiologieTags : U. lactuca polysaccharides lectins anti-inflammatoire immune-modulatoire antioxydant anti-inflammatory immuno-modulatory antioxidant أولفا لاكتوكا عديد السكاريد اللكتينات عديد الفينول مضاد الأكسدة مضاد الالتهاب Index. décimale : 570 Sciences de la vie. Biologie Résumé : The number of studies of marine algae extracts from the Algerian species Ulva lactuca is so little. This study aims to examine the biological potential of polyphenoles, polysaccharide and lectins fractions of the species U. lactuca collected from eastern Algeria (Jijel). The polyphenoles fractions was evaluated by testing the antioxidant activity in vitro, the carrageenin-induced anti-inflammatory activity in the Albino wistar rat, and the immunomodulatory effect in vivo by assessing the index of phagocytosis. U. lactuca metabolites (polysaccharide and lectins) are also investigated for their ability to inhibit TNF-α synthesis and NO release in LPS-stimulated RAW 264.7 macrophages. The gastroprotective effect of the polysaccharide phase on inflammatory and ulcerative lesions of the gastric mucosa was estimated by the animal model of gastric alterations induced by intra- gastric
administration of the gastric mucosa of absolute ethanol. All of these studies was supported by minute
microscopic and macroscopic examinations. The results show that the polyphenol phase has proved an antioxidant potential in vitro. The polysaccharide and lectin phases showed a significant antiedema effect. Decreases in MPO activity and MDA levels in inflammatory rat foot tissues were significant in the case polysaccharide phase compared to lectins. Both phases increased the phagocytic activity of macrophages in vivo, although this increase was more pronounced in groups treated with the lectin phase. Both phases exerted a protective effect against LPS-induced inflammation in RAW264 cells and revealed a significant dependent dose down regulating the production of NO by macrophages, TNF-α release; these effects were more obvious in the case of the polysaccharide phase. The results
of this study showed that Algerian U. lactuca has an important immunomodulatory activity due specifically to the lectin fraction and an anti- inflammatory effect due specifically to the polysaccharide fraction. The pre-treatment of mice with polysaccharide extract preserves biomarkers of altered gastric mucosa and compensate the deficiency of antioxidant defense mechanisms, GSH, CAT, SOD and GST, and eliminates lipid peroxidation. The histological study similarly confirmed an important restoration of the architecture of the gastric mucosa. Thus, the Algerian U. lactuca is endowed with an antioxidant, anti-inflammatory and gastroprotective potential, these properties could
be due to the synergistic effects of its constituents including specifically lectins and polysaccharides
Diplôme : Doctorat En ligne : ../theses/biologie/MEZ7286.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=10901 Potentiel antioxydant des algues des côtes de l’est Algérien. [texte imprimé] / Hichem Mezdour, Auteur ; Ahmed Menad, Directeur de thèse . - جامعة الإخوة منتوري قسنطينة, 2018 . - 119 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
BiologieTags : U. lactuca polysaccharides lectins anti-inflammatoire immune-modulatoire antioxydant anti-inflammatory immuno-modulatory antioxidant أولفا لاكتوكا عديد السكاريد اللكتينات عديد الفينول مضاد الأكسدة مضاد الالتهاب Index. décimale : 570 Sciences de la vie. Biologie Résumé : The number of studies of marine algae extracts from the Algerian species Ulva lactuca is so little. This study aims to examine the biological potential of polyphenoles, polysaccharide and lectins fractions of the species U. lactuca collected from eastern Algeria (Jijel). The polyphenoles fractions was evaluated by testing the antioxidant activity in vitro, the carrageenin-induced anti-inflammatory activity in the Albino wistar rat, and the immunomodulatory effect in vivo by assessing the index of phagocytosis. U. lactuca metabolites (polysaccharide and lectins) are also investigated for their ability to inhibit TNF-α synthesis and NO release in LPS-stimulated RAW 264.7 macrophages. The gastroprotective effect of the polysaccharide phase on inflammatory and ulcerative lesions of the gastric mucosa was estimated by the animal model of gastric alterations induced by intra- gastric
administration of the gastric mucosa of absolute ethanol. All of these studies was supported by minute
microscopic and macroscopic examinations. The results show that the polyphenol phase has proved an antioxidant potential in vitro. The polysaccharide and lectin phases showed a significant antiedema effect. Decreases in MPO activity and MDA levels in inflammatory rat foot tissues were significant in the case polysaccharide phase compared to lectins. Both phases increased the phagocytic activity of macrophages in vivo, although this increase was more pronounced in groups treated with the lectin phase. Both phases exerted a protective effect against LPS-induced inflammation in RAW264 cells and revealed a significant dependent dose down regulating the production of NO by macrophages, TNF-α release; these effects were more obvious in the case of the polysaccharide phase. The results
of this study showed that Algerian U. lactuca has an important immunomodulatory activity due specifically to the lectin fraction and an anti- inflammatory effect due specifically to the polysaccharide fraction. The pre-treatment of mice with polysaccharide extract preserves biomarkers of altered gastric mucosa and compensate the deficiency of antioxidant defense mechanisms, GSH, CAT, SOD and GST, and eliminates lipid peroxidation. The histological study similarly confirmed an important restoration of the architecture of the gastric mucosa. Thus, the Algerian U. lactuca is endowed with an antioxidant, anti-inflammatory and gastroprotective potential, these properties could
be due to the synergistic effects of its constituents including specifically lectins and polysaccharides
Diplôme : Doctorat En ligne : ../theses/biologie/MEZ7286.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=10901 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité MEZ/7286 MEZ/7286 Thèse Bibliothèque principale Thèses Disponible
