Spatio-temporal Dynamics of bush fires in Mont Péko national Park (West-Côte d'Ivoire)

Following the 2016 break-out of illegally settled populations in Mont Péko national Park due to the political-military crises of 2002 to 2011, the phenomenon of uncontrolled wildfires reached alarming proportions. The purpose of this study was to determine, from the combined use of remote sensing and geographic information systems, the evolution of the intensity and the spaces traversed by the fires in this protected area between 2016 and 2018. For this purpose, two Landsat 8 satellite images from 2016 (before fires) and 2018 (after fires) were used. The results of this work reveal that 49.63% of the total area of the protected area, located in its North and South-East part, was covered by fires. Analysis of the distribution of fires across the different land use classes reveals a greater occurrence of fires in the crop and fallow class (10 519.38 ha) compared to the forest class (3 963.87 ha) and the class of bare soils and rocky outcrops (538.02 ha). Overall, the severity of fires in the park following the study period is moderate

Etat Actuel de la Diversité Floristique du Parc National du Mont Péko en Côte d’Ivoire

Suite aux évènements politiques survenus en 2002 en Côte d'Ivoire, le Parc national du Mont Péko a connu une forte anthropisation qui a impacté son intégrité écologique. La présente étude a pour objectif d’évaluer la diversité floristique du parc après cette décennie de crise afin de contribuer à l'élaboration des stratégies de conservation. La collecte des données sur la flore a combiné la méthode de relevé de surface et celle dite itinérante. 66 relevés floristiques ont été réalisés chacun sur une aire minimale de 400 m², équitablement répartis entre les forêts, les jachères et les parcelles aménagées par l’Office Ivoirien des Parcs et Réserves. Les données collectées ont permis de noter que malgré les perturbations constatées dans un passé récent, la flore du parc reste encore riche et très diversifiée. Un total de 470 espèces appartenant à 326 genres et 92 familles botaniques a été inventorié. Les familles les mieux représentées sont les Euphorbiaceae et les Rubiaceae. Le spectre biologique indique une prédominance des phanérophytes (89 %). Sur le plan chorologique, les espèces guinéo-congolaises (GC) dominent la flore du parc à 69 %. En outre, 105 espèces à statut particulier ont été identifiées d’où l’urgence de sauver cette aire protégée fragilisée et menacée de disparition. Following the political events in 2002 in Côte d'Ivoire, the Mont Péko national Park experienced a strong enthronization that impacted its ecological integrity. The objective of this study is to assess the park’s floristic diversity after this decade of crisis in order to contribute to the development of conservation strategies. The collection of data on flora combined the surface survey method and the so-called itinerant method. 66 floristic surveys were carried out each on a minimum area of 400 m², equitably distributed between forests, fallow land and plots managed by the Ivorian Office of Parks and Reserves. The data collected made it possible to note that despite the disturbances observed in the recent past, the park’s flora is still rich and very diversified. A total of 470 species belonging to 326 genera and 92 botanical families were inventoried. The best represented families are Euphorbiaceae and Rubiaceae. The biological spectrum indicates a predominance of phanerophytes (89%). In chorological terms, Guineo-Congolese species dominate the park’s flora at 69%. In addition, 105 species with special status have been identified from where the urgent need to save this fragile and threatened protected area of disappearance

Effet des durées de conservation et du traitement à l’eau sur la germination des graines de Tieghemella heckelii Pierre ex A. Chev. (Sapotaceae) en Côte d’Ivoire

Le Makoré est une espèce de bois d’oeuvre de grande valeur commerciale, en danger de disparition dans les forêts tropicales. Cependant, la germination des graines fraiches et celles séchées et conservées est peu connue par l’homme. C’est pourquoi, cette étude vise à maitriser les paramètres de germination des graines de Makoré, afin de l’utiliser dans les reboisements des forêts classées en Côte d’Ivoire, en vue de sa pérennisation. Spécifiquement, il a été question de déterminer le délai de germination, la durée de germination et le taux de germination des graines. Pour ce faire, 5 lots de graines ont été constitués en fonction des durées de conservation sur lesquels 4 traitements à l’eau de robinet ont été appliqués. Les résultats ont montré que le lot 1 ou témoin (graines fraiches), le lot 2 (graines conservées pendant 14 jours) et le lot 3 (graines conservées pendant 21 jours) ont présenté des taux de germination, respectivement, de l’ordre de 72, 22, 55,56 et 41,67%. Le trempage des graines dans l’eau de robinet a réduit considérablement le délai de germination des graines du lot 1 à 25 jours et a relevé le taux de germination du prétraitement 4 du lot 1 (graines ayant séjourné dans l’eau pendant 6 jours) à 100%. Il ressort de cette étude que pour produire des plants de Makoré, les graines fraiches et celles séchées et conservées pendant deux et trois semaines peuvent être utilisées.Mots clés: Makoré, espèce menacée, conservation des graines, prétraitement, paramètres de germination, Côte d’Ivoire.   English Title: Effect of storage times and water treatment on germination of the seeds of Tieghemella heckelii Pierre ex A. Chev. (Sapotaceae) in Côte d’Ivoire Makoré is a timber species of great commercial value, in danger of disappearing in tropical forests. However, the germination of fresh seeds and those dried and preserved is little known by man. That is why, this study aims to control the seeds germination parameters of Makoré, in order to use it in the reforestation of the classified forests in Côte d’Ivoire, with a view to its perpetuation. Specifically, there has been talk of determining germination time limit, germination duration and seed germination rate. To do this, 5 lots of seeds were constituted according to the storage periods on which 4 treatments with tap water were applied. The results showed that the lot 1 or control (fresh seeds), lot 2 (seeds stored for 14 days) and lot 3 (seeds stored for 21 days) showed germination rates, respectively, of the order of 72.22, 55.56 and 41.67%. Soaking of the seeds in the tap water significantly reduced the germination time limit of seeds from lot 1 to 25 days and increased the germination rate of pretreatment 4 of lot 1 (seeds having remained in water for 6 days) 100%. This study shows to produce seedlings, fresh seeds and those dried and stored for two and three weeks can be used.Keywords: Tieghemella heckelii, threatened species, storage seeds, pretreatment, germination parameters, Côte d’Ivoire

The geo-history of urban land governance in Côte d’Ivoire: An analysis of urban sprawl in Bouaké

African cities are characterized by urbanization, social and economic problems that very often favor crises in the development of their spaces. The city of Bouake, in the center of Côte d'Ivoire, has been experiencing urban sprawl since 1980. This urban sprawl is the result of shortcomings in urban land governance in Côte d'Ivoire following several land reforms. This study analyzes the successions of urban land reforms poorly suited to population growth and a difficult economic context in Bouake. The results obtained, from documentary research supported by field surveys, have revealed that the sprawl of the city of Bouake, as it appears today, is the result of a long process of land reforms rooted both in the history of the city, land planning and urbanization policies. The analysis of this spread territory from multifactorial analyzes has revealed that Bouake is characterized by a complex space, animated by dynamics of very marked socio-spatial differentiations. Several socio-economic factors and urban policies are very decisive in this phenomenon which continues to marginalize peri-urban households, increasingly subject to constraints of access to infrastructure, concentrated in the town center. This uncontrolled extension therefore leads to reconsider the evolution of the spatial occupation of Bouake

Le rôle des langues endogènes dans le processus de développement économique de la Côte d’Ivoire

Résumé : Le français est la langue officielle de la Côte d’Ivoire. C’est donc au moyen de cette langue que le pays élabore et diffuse sa politique et ses projets de développement. Toutefois, l’analyse de la situation économique, du profil sociolinguistique de la population ivoirienne, de son système de communication gouvernementale à la lumière de la théorie de la modernisation et de la communication pour le développement révèle que les langues endogènes jouent un rôle capital qui n’est pas suffisamment mis en avant. Au regard de l’important rôle qu’elles jouent en dépit de leur minoration, il apparaît nécessaire de les promouvoir pour en faire de véritables sources de développement pour faciliter l’accès à l’information et créer un environnement favorable à une gestion inclusive des affaires publiques et surtout créer un environnement favorable à un développement participatif

Biologie De La Reproduction Du Sciaenidae Pseudotolithus Elongatus Dans La Lagune Ebrie (Cote d’Ivoire)

The study of reproduction of Pseudotolithus elongatus in the Ebrie lagoon was investigated between July 2013 and June 2015 on a whole of individuals of 550 specimens. the total length ranges from 14.5 to 42.7 cm. The monthly evolution of the gonado-somatic index (GSI), the liver-somatic index (LSI), the condition factor (K), the Sex-ratio, the fecundity, the diameter of eggs revealed that this species spawns throughout the year but the main breeding period was in raining season. Sex-ratio observed was in favour of females (1: 1. 14; X2 = 2.26; p > 0.05). The percentage of mature specimens by sexes was calculated for each size class. Total length at first maturity was 21.06 cm for females and 20.21cm for males. The ripe ovaries contained 39883-814757 eggs. The relative fecundity was 216-1979 eggs per g of body weight of females. And the mean diameter of eggs is 336 ±138 microns

Feeding Habits of Polynemids: Polydactylus Quadrifilis, Galeoides Decadactylus, and Pentanemus Quinquarius of the Continental Shelf of Grand-Lahou, Côte d’Ivoire

This paper focuses on the threadfins Polydactylus quadrifilis, Galeoides decadactylus, and Pentanemus quinquarius captured by the maritime traditional fishing of Grand-Lahou in Côte d'Ivoire. It aims to determine their feeding habits based on weighing, measuring of body, and intestine height and identification of prey. The specimens of Polydactylus quadrifilis with height lower than 55 cm have an average of 12±1 intestinal filaments, whereas those of height higher than 100 cm have an average of 20±2 of them. This average is constant concerning Galeoides decadactylus (12±2) and Pentanemus quinquarius (11±2), for all height. The specimens of Polydactylus quadrifilis consume mainly fish (74.45%), followed by shrimps (10.06%). The juvenile ones of less than one year prefer shrimps (80.28%), whereas fish are preferred (87.07) by the older individuals. Whatever their age, Galeoides decadactylus and Pentanemus quinquarius mainly consume shrimps in the ratio of 83.11% and 68.75% respectively. The relative yearly food consumption reveals for Polydactylus quadrifilis a quantity of 0.124 T/Km2 /year, whereas that of Galeoides decadactylus is 0.02 T/Km2 /year. As for the specimens of Pentanemus quinquarius, they consume 0.013 T/Km2 /year. Threadfins have very short intestine (IC < 1) relatively to the intestinal coefficient. Their food habit is relating to stomach and intestine capabilities

Lead concentrations in sediments and mollusc gastropod from Vridi Canal, Côte d’Ivoire

Lead (Pb) is one of the most frequent and toxic contaminant in the environment. It can be bioaccumulated by marine organisms through contaminated sediments as well as their food chains. The current study aimed at investigating Pb occurrence in the sediments and gastropod P. haemastostoma from Vridi Canal. Sediment samples were taken using a Van Veen steel grab of 0.02 m2 area, sealed in plastic bags and transported to the laboratory at 4 °C. Gastropod P. haemastostoma species were collected manually using gloves, and then placed in polyethylene plastic bags. The different concentrations were determined using atomic absorption spectrometer Varian AA 20. The results showed seasonal variability of Pb concentrations in sediments and P. haemastostoma. In the both matrices, Pb exhibited the same trend in the distribution between the seasons. This study also mentioned that sediments were highly  contaminated by Pb (54.27-134.71 mg/kg). Vridi Canal was found to be one of the most contaminated seaport area. Pb levels  (49.55-104.19 mg/kg) in P. haemastostoma exceeding the maximum permitted levels according to the United Nations Food and Agriculture Organization (FAO). This research demonstrated that sediments having lower ecological risk may be resulting in lower tissue Pb of P. haemastostoma. Keywords: Metal Pb, sediment, P. haemastostoma, seasonal variatio