Floristic and phytogeographycal analysis of coastal and subcoastal vegetation in the Kouilou Department (Republic of Congo)

The zone of study is located north of Pointe noire town, in the Department of Kouilou, in Republic of Congo. In order to better understand the floristic richness and chorology of the study site of interest, an analysis on a flora, of the autoecological and phytogeographycal spectra of species was undertaken. This analysis is based on the floristic material from different botanical surveys carried out in 2012, and deposited at the National Herbarium of the Congo (IEC). Over a study area of 202’700 ha investigated through 243 phytosociological plots, a matrix of 580 specific and subspecific taxa, distributed in 386 genus and 119 families, were inventoried. Seven species, of which one for the science, were new for the flora of Republic of Congo. The families of Fabaceae, Poaceae, Rubiaceae, Euphorbiaceae, of Malavaceae and Annonaceae and are the most diversified in species. The ecological spectrum highlights the strong preponderance of the phanerophytes, sarcochores and mesophiles, thereby confirming the dominance of the forest biodiversity compared to grasslands. From a phytogeographical perspective, the preponderance of the base element identified as well as three families and eleven genus of endemic nature integrate the flora within the Guineo-Congolian centre of endemism.La zone d’étude est située au nord de Pointe noire, dans le Département du Kouilou, en République du Congo. Pour mieux connaître la richesse floristique et la position chorologique du site d’intérêt, une analyse sur la flore, des spectres autoécologiques et phytogéographiques des espèces a été entreprise. Cette analyse est basée sur le matériel floristique issu de différentes prospections botaniques effectuées en 2012, et déposé à l’Herbier National du Congo (IEC). Sur une superficie de 202.700 hectares prospectée, au travers de 243 relevés phytosociologiques, une matrice floristique de 580 espèces et taxons infra spécifiques réparties en 386 genres et en 119 familles, a été retenue. Sept nouvelles espèces, dont une nouvelle pour la science, sont des ajouts à la flore du Congo. Les familles des Fabaceae, des Poaceae, des Rubiaceae, des Euphorbiaceae, des Malavaceae et des Annonaceae et sont les plus diversifiées en espèces. Les spectres écologiques mettent en relief la forte représentativité des phanérophytes, des sarcochores et des mésophylles, confirmant de facto la prépondérance de la biodiversité forestière par rapport aux formations herbacées. Sur le plan phytogéographique, la prépondérance de l’élément base décelé ainsi que la présence de trois familles et de onze genres endémiques, intègrent bien cette flore au Centre d’endémisme guinéo-congolais.http://www.ijias.issr-journals.org/am2017Centre for Wildlife Managemen

Floristic composition, diversity and structure of the forest communities in the Kouilou Département, Republic of Congo

The objectives of the study were to classify, describe and map the forest communities in the study area and to investigate possible gradients in plant diversity. The study area comprised approximately 166 000 ha in the Kouilou Département, Republic of Congo, a section of land targeted for extensive future development. In total 156 forest sample sites were surveyed using the Braun-Blanquet method of phytosociology. Diversity of each plant community was expressed in terms of species richness; Shannon-Wiener index; exponent of Shannon-Wiener index; evenness; Fisher's alpha; Simpson’s index; and inverse Simpson index. Eleven plant communities were described and mapped at a much finer scale than has been done previously. The communities were arranged along two gradients: a degraded – relatively intact gradient and a wet – dry gradient. The least degraded communities, and consequently those with the highest conservation value, were the swamp forests and the okoumé forest. Overall, the values reported for the diversity parameters in the current study were within the range reported for other tropical forests in Central Africa. The study revealed a gradient between the coast (west) and the Mayombe mountain range (east) in plant diversity linked to topography and climate with plant diversity lowest at the coast. Furthermore, plant diversity was negatively related to the distance to human infrastructure. The forest communities appear to be fairly resilient to past anthropogenic disturbances, however, there is no historical analogue to the more severe types of forest destruction associated with some of the future developments anticipated, such as mechanized logging or mining.http://journals.cambridge.org/action/displayJournal?jid=TRO2017-06-30hb2017Centre for Wildlife ManagementPlant Scienc

Aspects de l’évolution du cadre décisionnel présidentiel sous Reagan

L’article examine la contribution de Ronald Reagan à l’évolution du cadre décisionnel présidentiel. Se fondant sur une analyse historique comparative, plus particulièrement depuis F. D. Roosevelt, de la présidence moderne et de ses rouages, on y décrit l’action d’un chef de l’exécutif contrôlant le processus décisionnel grâce à l’idéologie. Cette façon de faire ne lui épargnera cependant pas les crises et les conflits qui révèlent le fossé entre discours et réalité dans la politique américaine.The paper presents an evaluation of Ronald Reagan's contribution to the evolution of the presidential decision-marking process in the U.S. The action of a chief-executive controling the decision-making process through an ideological discourse is described. It is based on a comparative historical analysis of the modern presidency and its functions, particularly since F. D. Roosevelt. While president Reagan's way of operating this process did not save him from crises and conflicts revealing the gap between ideological discourse and reality which constitutes American politics