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1.
Braz J Biol ; 84: e273662, 2024.
Article de Anglais | MEDLINE | ID: mdl-38536974

RÉSUMÉ

Benthic macroinvertebrates are integral parts of inland waters, inhabiting a diversity of aquatic ecosystems where communities are spatially structured. Macroinvertebrates of some Mediterranean regions such as North Africa are still not well studied. Due this reason we proposed study the community structure in water bodies located in Northeastern Algeria. For this objective, we sampled 12 different kind of water bodies, two dams, three rivers, and seven streams during the period from October 2020 to September 2021. To biotic and abiotic data, a redundancy analysis (RDA) was applied with the aim of determine the role of both kind of variables for grouping the sites. Also, two types of Null models were considered: species co-occurrence and niche sharing for study the potential associations between species reported. Redundancy analysis showed that water velocity and conductivity were the main drivers of community structure of macroinvertebrates. The species co-occurrence results reveal that species associations are ramdom, except for two sites: El fadjoudj and Ain ben baida corresponding to Seybouse river. At the same time, there is no niche sharing and in consequence, there is no interspecific competition except in the two sites: Salah Salah Salah stream and Bouhamdane dam. The results revealed similarities with other similar studies for Algerian rivers and dams, and with other similar water bodies with Mediterranean climate.


Sujet(s)
Écosystème , Invertébrés , Animaux , Algérie , Rivières/composition chimique , Climat , Surveillance de l'environnement
2.
Braz J Biol ; 83: e273010, 2023.
Article de Anglais | MEDLINE | ID: mdl-37585930

RÉSUMÉ

Aquatic macroinvertebrates are integral parts of functioning wetlands, inhabiting a diversity of aquatic ecosystems where communities are spatially structured. Macroinvertebrates of some Mediterranean regions such as North Africa are still not well studied. Here, we study the community structure of benthic macroinvertebrates in four different types of lotic and lentic wetlands in the semiarid Haut Plateaux of Northeast Algeria. Macroinvertebrates and 06 physicochemical parameters were sampled in 12 sites belonging to four types of habitats (lotic river, lentic river, dams, and sebkha [saline lentic water body]) during January-December 2021. Eventually, the character lentic-lotic was the most important variable affecting the affecting invertebrate communities in the Mediterranean region. The results revealed that sebkha and dams had a lower Shannon index than lentic and lotic rivers. Non-metric multidimensional scaling analysis showed a strong overlap between the community composition in lotic and lentic sites . Howeverin the three types of aquatic groups lentic river, dam and lotic habitats showed a strong overlap between the community whereas sebkha was markedly separated. Redundancy analysis showed that water velocity and pH, were the main drivers of community structure of macroinvertebrates, revealed a strong effect with pH (F1,8=4.15, P = 0.001) and water velocity (F1,8= 3.22, P = 0.002) , separating lotic communities from those that inhabited dams, lentic rivers, and sebkhas. As conclusion, this study contributes to the better understanding of the community structure of macroinvertebrates in semiarid North Africa where wetlands have been experiencing high anthropogenic disturbance.


Sujet(s)
Écosystème , Invertébrés , Animaux , Algérie , Rivières/composition chimique , Eau , Surveillance de l'environnement
3.
Braz. j. biol ; 83: e273010, 2023. tab, graf, mapas
Article de Anglais | VETINDEX | ID: biblio-1505864

RÉSUMÉ

Aquatic macroinvertebrates are integral parts of functioning wetlands, inhabiting a diversity of aquatic ecosystems where communities are spatially structured. Macroinvertebrates of some Mediterranean regions such as North Africa are still not well studied. Here, we study the community structure of benthic macroinvertebrates in four different types of lotic and lentic wetlands in the semiarid Haut Plateaux of Northeast Algeria. Macroinvertebrates and 06 physicochemical parameters were sampled in 12 sites belonging to four types of habitats (lotic river, lentic river, dams, and sebkha [saline lentic water body]) during January-December 2021. Eventually, the character lentic-lotic was the most important variable affecting the affecting invertebrate communities in the Mediterranean region. The results revealed that sebkha and dams had a lower Shannon index than lentic and lotic rivers. Non-metric multidimensional scaling analysis showed a strong overlap between the community composition in lotic and lentic sites . Howeverin the three types of aquatic groups lentic river, dam and lotic habitats showed a strong overlap between the community whereas sebkha was markedly separated. Redundancy analysis showed that water velocity and pH, were the main drivers of community structure of macroinvertebrates, revealed a strong effect with pH (F1,8=4.15, P = 0.001) and water velocity (F1,8= 3.22, P = 0.002) , separating lotic communities from those that inhabited dams, lentic rivers, and sebkhas. As conclusion, this study contributes to the better understanding of the community structure of macroinvertebrates in semiarid North Africa where wetlands have been experiencing high anthropogenic disturbance.


Macroinvertebrados aquáticos são partes integrantes de zonas úmidas em funcionamento, habitando uma diversidade de ecossistemas aquáticos onde as comunidades são espacialmente estruturadas. Os macroinvertebrados de algumas regiões mediterrâneas, como o norte da África, ainda não foram especificamente analisados. Neste trabalho, almejou-se analisar a estrutura da comunidade de macroinvertebrados bentônicos em 4 tipos diferentes de pântanos lóticos e lênticos no semiárido Haut Plateaux do nordeste da Argélia. Os macroinvertebrados e 6 parâmetros físico-químicos foram amostrados mensalmente em 12 locais pertencentes a 4 categorias de habitats diferentes (rio lótico, rio lêntico, barragens e sebkha - corpo de água salina lêntica) de janeiro a dezembro de 2021. Os resultados revelaram que sebkha e barragens tiveram um pH mais baixo do que os rios lênticos e lóticos. A análise de escala multidimensional não-métrica mostrou uma forte sobreposição entre a composição da comunidade em sítios lóticos e lênticos, mas nos 3 tipos de sítios lênticos, barragem e rio lêntico mostraram uma forte sobreposição, enquanto sebkha foi marcadamente separado. A análise de redundância mostrou que a velocidade da água e o pH foram os principais impulsionadores da estrutura da comunidade de macroinvertebrados, separando as comunidades lóticas daquelas que habitavam barragens, rios lênticos e sebkhas. Assim, à guisa de conclusão, este estudo contribui para a melhor compreensão da estrutura da comunidade de macroinvertebrados no semiárido norte da África, onde as zonas úmidas têm sofrido alta perturbação antrópica.


Sujet(s)
Animaux , Faune Aquatique , Faune Benthique , Invertébrés , Algérie
4.
Genet Mol Res ; 15(1)2016 Mar 31.
Article de Anglais | MEDLINE | ID: mdl-27051021

RÉSUMÉ

Sequence-related amplified polymorphism (SRAP) markers were used to evaluate the intra- and interspecific variation among 40 Lathyrus genotypes (four species) (Fabaceae). Ten SRAP primer combinations resulted in a total of 94 bands, and they exhibited high interspecific variability. The genetic differentiation among Lathyrus, estimated using AMOVA, was highly significant. The results indicated that 58% of the total genetic variation existed among species, and 42% of the differentiation was within species. This was explained by the high level of genome conservation of these species as well as the recent and slow evolution of this genus. These results were confirmed by the topology of the neighbor-joining cladogram and the results of the principal coordinate analysis. Our data support previous results based on seed protein diversity. These results make SRAP markers choice markers for the study of functional polymorphism that is directly related to the transcriptomic data. The SRAP markers used in this study provide an accurate picture of the population structure within Lathyrus germplasm, which is critically important information for the design of genetic diversity and structure analyses. Moreover, further extensive studies are necessary to fully examine other Lathyrus species and tests that adopt the SRAP technique to enrich the Lathyrus library for next-generation sequencing, thus providing a potent protocol for the study of polymorphism.


Sujet(s)
Variation génétique/génétique , Lathyrus/génétique , Lathyrus/classification , Phylogenèse , Protéines végétales/génétique , Polymorphisme génétique/génétique
5.
Genet Mol Res ; 13(4): 8729-39, 2014 Oct 27.
Article de Anglais | MEDLINE | ID: mdl-25366764

RÉSUMÉ

Phylogenetic relationships in the Lathyrus genus were examined using cpDNA data, particularly data attributed to the "barcode" rbcL gene to construct a possible evolutionary scenario. Plant barcoding can be used to differentiate between species within a genus and to conserve DNA within the same species. We assessed the phylogeny of 29 species of Lathyrus using maximum parsimony, maximum likelihood and unweighted pair-group method and arithmetic mean. The classifications did not agree with current morphological and basic Lathyrus classification. Lathyrus belinensis is a new species that was not described by Kupicha; according to rbcL analysis, the species belongs in the Lathyrus genus. Additionally, the genus Lathyrus has undergone a rapid population expansion as indicated by neutral selection indices.


Sujet(s)
Évolution moléculaire , Lathyrus/génétique , Ribulose bisphosphate carboxylase/génétique , Classification/méthodes , Lathyrus/classification , Phylogenèse
6.
Genet Mol Res ; 13(1): 1548-62, 2014 Mar 12.
Article de Anglais | MEDLINE | ID: mdl-24668629

RÉSUMÉ

Six Medicago species were investigated to characterize and valorize plant genetic resources of pastoral interest in Morocco. Samples were obtained from the core collection of the South Australian Research and Development Institute (SARDI). The transferability of single sequence repeat markers of Medicago truncatula was successful with 97.6% efficiency across the five species. A total of 283 alleles and 243 genotypes were generated using seven SSR markers, confirming the high level of polymorphism that is characteristic of the Medicago genus, despite a heterozygosity deficit (HO = 0.378; HE = 0.705). In addition, a high level of gene flow was revealed among the species analyzed with significant intra-specific variation. The unweighted pair group method with arithmetic mean dendrogram generated by the dissimilarity matrix revealed that M. polymorpha and M. orbicularis are closely related, and that M. truncatula is likely the ancestral species. The Pearson correlation index revealed no significant correlations between the geographic distribution of the Moroccan species and genetic similarities, indicating local adaptation of these species to different ecological environments independent of their topographical proximities. The substantial genetic variation observed was likely due to the predominance of selfing species, the relative proximity of prospected sites, human impacts, and the nature of the SARDI core collections, which are selected for their high genetic diversity. The results of this first report on Moroccan Medicago species will be of great interest for establishing strategies aiming at reasonable management and selection programs for local and Mediterranean germplasm in the face of increasing environmental change.


Sujet(s)
Variation génétique , Medicago/génétique , Répétitions microsatellites/génétique , Phylogéographie , Allèles , Génome végétal , Humains , Polymorphisme génétique
7.
s.l; s.n; 1973. 9 p. ilus.
Non conventionel de Français | Sec. Est. Saúde SP, HANSEN, Hanseníase Leprosy, SESSP-ILSLACERVO, Sec. Est. Saúde SP | ID: biblio-1234559

Sujet(s)
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