Ufr Environnement

Limited to the Atlantic and its surrounding basins, the expression of the Coniacian–Santonian oceanic anoxic event (OAE3) was discovered in the non-marine Cretaceous Songliao Basin, Eastern Asia not long ago. In this study, based on spectral gamma ray logs data recorded in three basins, the self-similarity of the OAE3 was studied through the analysis of the scaling properties of thorium–potassium and thorium–uranium distributions both in marine and terrestrial environments using the multifractal detrending fluctuation analysis. The results indicate that, in both marine and terrestrial systems, the OAE3 intervals are characterized by their multifractal nature due to long-range correlation. However, the multifractal features of the studied OAE3 intervals are different in the three basins, although some common trends were observed. By comparing the degree of multifractality of the OAE3 deposits with the clay minerals and the redox conditions, it appears that the changes of the multifra...

The Cretaceous interval is marked by several important geological changes whose prints are buried in both continental and marine sytems. Although significant paleoenvironmental details of this period have been inferred from biological and geochemical indicators, little is known about the physical proxies. Through scientific borehole data, petrophysical properties of Upper Cretaceous Songliao Basin (SB) in NE China and Goban Spur Basin (GSB) in NW Europe were intercorrelated to investigate the critical geological paleoenvironmental shifts and their petrophysical responses, through statistical, wavelet and spectral approaches. The results demonstrated that petrophysical features, particularly gamma-ray and resistivity reactivities, were responsive to past environmental changes in both terrestrial and marine systems. Shifts in organic-rich shale deposition and brine bearing shale showed a correlation to a probable period of seawater incursion in SB, while the gamma log, resistivity and...

This study aims to improve our knowledge of the subsurface geology, and to create a comprehensive geological framework to highlight potential opportunities in the region. It involved analyzing the electrical and magnetic parameters of the subsurface formations, comparing dipole-dipole electrical resistivity and Schlumberger borehole data with magnetic data, and then determining the level of alteration by means of conductive and resistant anomalies. The results reveal that the area is characterized by resistant anomalies and a high magnetic field of felsic formations, extending over a total area of 85.56 ha and covered by a thick layer of alteration averaging 15 m in depth. These formations span the entirety of the eastern portion of the study area, and isolated areas situated to the west and southwest. A major network of fractures running NE-SW and NNE-SSW was highlighted through the analysis of the conductive anomalies. Overall, this study has enabled us to use a geophysical approach to distinguish the spatial distribution of the sound lithological series in the area, the degree of alteration of the series and the related fracture and fault systems, which could serve as a valuable guide for any mineral resource and aggregate exploration activity in the region.

This work aims to understand the geological framework of the mineralization and to establish the relationship between the gold deposit and the geology of the area. It is based on the use of optical and radar images and supplemented by a field campaign. The study yielded structural or linear maps of the study area, covering an area of 471.38 Km². The detailed map of fractures obtained after validation includes more than 6,500 fractures. The remote sensing tools have thus made it possible to draw up an updated structural diagram of the study area. The area is marked by intense fracturing, with the main directions being N00-N010, NE-SW (N040-N080) and N090-N120. The central and northeastern sectors of the study area are the most interesting and correspond to the strongest geochemical anomalies in gold and lineament density over the entire study area. The structural study highlighted two shear zones, one N010-N025 sinister, the other N110-N120 dexter, within volcanic, metamorphic and plutonic formations, which are thought to be responsible for the gold mineralization of these formations. This work has enabled us to highlight the vector of mineralization in the area and the origin of the current architecture of the geological formations in the region.

L'objet de cet article est l'identification et la cartographie des zones à risque d'inondation de la région semi-montagneuse à l'ouest de la Côte d'Ivoire. Il est fondé sur l'intégration dans un système d'information géographique (SIG), de données interprétées à partir d'images TM de Landsat, de produits dérivés d'un modèle numérique d'altitude (MNA) et des données hydroclimatiques. Le traitement des données comporte différentes phases : 1) création d'un MNA à partir des courbes de niveau et de points cotés extraits d'une carte topographique, 2) calcul de variables morphométriques à partir du MNA, 3) traitement numérique des images TM et cartographie thématique, 4) intégration des données (cartes thématiques issues des traitements d'images, MNA et images dérivées, données exogènes) et analyse spatiale dans un SIG. Les principaux facteurs de risque d'inondation considérés sont : la pluviosité, la couverture du sol, le réseau hydrographique, la pente du terrain et les domaines litho-structuraux. L'analyse spatiale multicritère, réalisée dans un SIG a permis d'élaborer la carte des aléas ainsi que celle de la vulnérabilité à l'inondation. La combinaison de ces deux cartes permet la cartographie des zones à risque d'inondation. Cette carte comporte quatre classes allant du faible risque au très fort risque d'inondation. Les zones à moyen et fort risque couvrent 65 % du territoire. Elles sont situées dans la partie australe et dans les plaines alluviales attenantes aux principaux cours d'eau (Sassandra, à l'ouest et Bafing au nord). La carte obtenue peut être utilisée non seulement pour la prévention des risques d'inondation mais aussi pour la gestion des ressources naturelles dans la région de Man (ouest de la Côte d'Ivoire).

Population of Ptychadena mascareniensis from Daloa city wetlands (Ivory Coast) were investigated for understand helminth infection pattern regarding to hosts' age and sex. A total of 115 specimens of this species were examined. From this population, 67 specimens were infected. We encountered 10 acanthocephalan, 157 nematoda and 231 trematoda. These helminth parasites were identified as Centrorhynchus sp. (acanthocephala), Cosmocercoides variabilis (nematoda) and Haplometroides eburnense (trematoda). The overall prevalence rates were high except for infections with acanthocephala. Adult hosts prevalence of nematoda and trematoda infections were higher than juveniles. No acanthocephalan was found from juveniles. The prevalence of each helminth in both sexes were almost the same values. The mean intensity of trematoda infection were higher than acanthocephala and nematoda infections. Thus, the highest values of intensity of acanthocephala and nematoda infections were obtained in females. In addition, the correlations between the age or the sex of frogs and the parasitic load were generally low and not significant (r ≤ 0.257; p ≥ 0.337). Only in juveniles, the number of trematodes increases with the size of host (r = 0.631; p = 0.016). Thus, helminth infection pattern was influenced by host diet behavior.

The objective of this study is to confirm the presence of four (4) Ophidian species (Atractaspis aterrina, Hapsidrophys smaragdina, Leptotyphlops albiventer, and Lycophidion irroratum) in the Taï National Park and to collect additional data on their morphological characteristics and habitats. The habitats prospected are secondary forests, characterized by the presence of herbaceous plants, shrubs and dwellings, and primary forests, marked by the presence of large trees with a canopy more than 80% closed and a ground covered with more than 90% dead leaves. Ophidian sampling in the park took place throughout twenty-five (25) days (May 15 to October 25, 2018). The presence of these species in the primary and secondary forests of Taï National Park would be related to their ecological plasticity.

Infections parasitaires deHoplobatrachus occipital(Günther, 1858) depuis Étang et Peu profond à Daloa Ville (Côte D'ivoire) Mots clés: Prévalence, Intensité de l'infection, ville de Daloa Parasites, Hoplobatrachus occipital, ABSTRAIT 1*N'guessan Emmanuel ASSEMIAN,1Konan Hervé OUSSOU,1Gaoussou KEITA,1Païbo Yannick POPE Les infections parasitaires deHoplobatrachus occipital provenant d'étangs et de bas-fonds de la ville de Daloa (Côte d'Ivoire) ont été étudiés. Un total de 55 spécimens deH. occipitalont été examinés et les parasites récupérés comprenaientClinostomum complanatum,Enterobius vermicularisetRhabditesp. Les résultats obtenus montrent une prévalence élevée et une intensité moyenne d'infection de Clinostomum complanatumauH. occipitaldans les étangs. A noter que plusieurs paramètres pourraient expliquer ces observations, à savoir la variation de température à laquelle les amphibiens sont sensibles, l'acidité de l'eau des étangs. De plus, les parasites ont été trouvés dans le gros intestin, l'intestin grêle et l'estomac des individus capturés.

This study aimed to confirm the presence of Amnirana galamensis in the Taï National Park (a west Africa evergreen forest), and to collect additional data on ecology and morphology of these frogs. The study was carried out over a period from March 26 to April 14 2020. A population of 33 specimens of A. galamensis was found in the North of Taï National Park: six females and three males were captured; four frogs were observed and 20 calls were recorded. The snout-urostyle-lengths of A. galamensis 's males ranged between 45-52 mm, those of females ranged between 53-57 mm. The survey area was characterized by the presence of bamboos, grasses, household garbage, damaged canoes, houses, potato fields. The presence of A. galamensis in this area of this park brings a clear indication of the advanced degradation of some habitats of this protected area located in forest block in southwestern Ivory coast.

The conversion of tropical rain forests to agricultural systems is a major threat to tropical biodiversity. In West Africa, studies investigating the effects of this habitat conversion on biodiversity are scarce. In this study, we investigated which forest amphibians survive in the agroforestry systems surrounding West Africa's largest area of protected rainforest, the Taï National Park (TNP) in southwestern Côte d'Ivoire. Species richness was assessed in different habitats types, i.e., a mosaic of coffee and cocoa plantations, rubber plantations, and rice fields, and compared to data from primary and degraded forests in TNP. The anuran assemblage composition differed considerably between forest and agroforestry systems, with the latter comprising only a small subset of generalist forest species and species which usually occur in highly degraded forest habitats or even savanna. Thus, the agroforestry systems in western Côte d'Ivoire seem to be unsuitable for the maintenance of the rich local and regional diversity of forest amphibians.

The parasitic infections of Hoplobatrachus occipitalis from ponds and shallows in Daloa city (Côte D'Ivoire) were investigated. A total of 55 specimens of H. occipitalis were examined and parasites recovered included Clinostomum complanatum, Enterobius vermicularis and Rhabditis sp. Results obtained show a high prevalence and mean infection intensity of Clinostomum complanatum at the H. occipitalis in the ponds. It should be noted that several parameters could explain these observations, namely the variation of the temperature to which the amphibians are sensitive, the acidity of the water in the ponds. Furthermore, the parasites were found in the large intestine, small intestine and stomach of the captured individuals.

This study reports the amphibian's fauna sampled from the Biodiversity Conservation Area of the hydroelectric dam of Soubré city (southwestern Côte d'Ivoire). This study aims to provide a better understanding of the diversity of amphibians in this relict forest of 200 ha, in order to assess the ecological health of this ecosystem for conservation and sustainable management perspectives. During dry season (from 26 February to 4 March 2018) and rainy season (from 17 to 23 June 2018), we recorded 14 species of anurans grouped into eight genera and six families. The study sites comprise an amphibian fauna consisting mainly of savannah specialists and degraded forest (64.28% of total species richness). Based on the IUCN Red List, all species recorded are of least concern. Also, these species are well distributed in the different regions of Côte d'Ivoire and Africa. Thus, it is necessary to monitor the ecology of the species and to protect subsequently the different habitats of this area.

The turtle population of Taï National Park (TNP), located in southwest Côte d'Ivoire, was surveyed to determine the diversity of turtles in this Park and to identify their preferred habitats. Data collection was carried out from April to October 2021 in different habitats of the park using the unmarked observation method. This method involved opportunistic sampling during reconnaissance walks for terrestrial species and baited traps were used for aquatic species. A total of four turtle species were recorded: two terrestrial species (Kinixys erosa and Kinixys homeana) and two aquatic species (Pelusios cupulatta and Trionyx triunguis). The turtle fauna study sites were composed of open undergrowth, closed undergrowth and swamp habitats for terrestrial turtles. Aquatic turtles were observed in the Meno River. According to the IUCN Red List, the species Kinixys homeana and Trionyx triunguis are classified as critically endangered and vulnerable respectively. As for the other two species, there is insufficient data to assess their international conservation status.

The turtle population of Taï National Park (TNP), located in southwest Côte d'Ivoire, was surveyed to determine the diversity of turtles in this Park and to identify their preferred habitats. Data collection was carried out from April to October 2021 in different habitats of the park using the unmarked observation method. This method involved opportunistic sampling during reconnaissance walks for terrestrial species and baited traps were used for aquatic species. A total of four turtle species were recorded: two terrestrial species (Kinixys erosa and Kinixys homeana) and two aquatic species (Pelusios cupulatta and Trionyx triunguis). The turtle fauna study sites were composed of open undergrowth, closed undergrowth and swamp habitats for terrestrial turtles. Aquatic turtles were observed in the Meno River. According to the IUCN Red List, the species Kinixys homeana and Trionyx triunguis are classified as critically endangered and vulnerable respectively. As for the other two species, there is insufficient data to assess their international conservation status.

The turtle population of Taï National Park (TNP), located in southwest Côte d'Ivoire, was surveyed to determine the diversity of turtles in this Park and to identify their preferred habitats. Data collection was carried out from April to October 2021 in different habitats of the park using the unmarked observation method. This method involved opportunistic sampling during reconnaissance walks for terrestrial species and baited traps were used for aquatic species. A total of four turtle species were recorded: two terrestrial species (Kinixys erosa and Kinixys homeana) and two aquatic species (Pelusios cupulatta and Trionyx triunguis). The turtle fauna study sites were composed of open undergrowth, closed undergrowth and swamp habitats for terrestrial turtles. Aquatic turtles were observed in the Meno River. According to the IUCN Red List, the species Kinixys homeana and Trionyx triunguis are classified as critically endangered and vulnerable respectively. As for the other two species, there is insufficient data to assess their international conservation status.

The bushmeat trade in tropical Africa represents illegal, unsustainable off-takes of millions of tons of wild game-mostly mammals-per year. We sequenced four mitochondrial gene fragments (cyt b, COI, 12S, 16S) in >300 bush-meat items representing nine mammalian orders and 59 morphological species from five western and central African countries (Guinea, Ghana, Nigeria, Cameroon and Equatorial Guinea). Our objectives were to assess the efficiency of cross-species PCR amplification and to evaluate the usefulness of our multilocus approach for reliable bushmeat species identification. We provide a straightforward amplification protocol using a single 'universal' primer pair per gene that generally yielded >90% PCR success rates across orders and was robust to different types of meat prepro-cessing and DNA extraction protocols. For taxonomic identification, we set up a decision pipeline combining similarity and tree-based approaches with an assessment of taxonomic expertise and coverage of the GENBANK database. Our multilocus approach permitted us to: (i) adjust for existing taxonomic gaps in GENBANK databases, (ii) assign to the species level 67% of the morphological species hypotheses and (iii) successfully identify samples with uncertain taxonomic attribution (preprocessed carcasses and cryptic lineages). High levels of genetic polymorphism across genes and taxa, together with the excellent resolution observed among species-level clusters (neighbour-joining trees and Klee diagrams) advocate the usefulness of our markers for bushmeat DNA typing. We formalize our DNA typing decision pipeline through an expert-curated query database-DNABUSHMEAT-that shall permit the automated identification of African forest bushmeat items.

The bushmeat trade in tropical Africa represents illegal, unsustainable off-takes of millions of tons of wild game - mostly mammals - per year. We sequenced four mitochondrial gene fragments (cyt b, COI, 12S, 16S) in >300 bushmeat items representing nine mammalian orders and 59 morphological species from five western and central African countries (Guinea, Ghana, Nigeria, Cameroon and Equatorial Guinea). Our objectives were to assess the efficiency of cross-species PCR amplification and to evaluate the usefulness of our multilocus approach for reliable bushmeat species identification. We provide a straightforward amplification protocol using a single 'universal' primer pair per gene that generally yielded >90% PCR success rates across orders and was robust to different types of meat preprocessing and DNA extraction protocols. For taxonomic identification, we set up a decision pipeline combining similarity- and tree-based approaches with an assessment of taxonomic expert...

Strauss, R. E., and F. L. Bookstein (Museum of Zoology, The University of Michigan, Ann
Arbor, Michigan 48109) 1982. The truss: body form reconstruction in morphometrics. Syst.
Zool., 31:113-135.-In principle, any measured distances between landmarks of a form may
serve as characters for morphometric analyses. Systematic studies typically are based on a
highly biased and repetitious sample of these. But collections of landmarks and the distances
among them must be homologous from form to form for comparisons to be meaningful, and
an adequate character set should at least permit the full reconstruction of the original configuration of landmarks.
We describe a geometric protocol for character selection, the truss network, which enforces
systematic coverage of the form and which exhaustively and redundantly archives the landmark configuration. Reconstruction of the form from truss measures provides Cartesian coordinates for landmarks and allows estimation of, and compensation for, measurement error.
Samples of forms may be averaged and standardized to one or more common reference sizes
by regression of measured distances on a composite measure of body size, followed by reconstruction of the form using distance values predicted by the regression functions at some
standard body size.
Principal component loadings of distance measures may be indicated directly on the truss
network to display patterns of within-group allometry or between-group shape differences.
Because the truss enforces use of cross measurements, discrimination among groups may be
enhanced. Composite mapped forms are useful in biorthogonal analyses of differences in
shape because they allow the comparison of averaged forms among samples. Certain patterns
of principal component loadings are concordant with, and provide an initial sampling of, the
biorthogonal grids for these deformations. [Allometry; biorthogonal analysis; discriminant
analysis; fishes; morphometrics; multivariate analysis; principal components; triangulation;
truss.]