A study was carried out in the Mount Mandara area to assess the populations and renewal status of Parkia biglobosa, a multipurpose species. The study was aimed at contributing to the sustainable management of this resource. Transect methods were used to count individuals of P. biglobosa in fields. Results showed that the density of P. biglobosa was 7 individuals ha-1. The basal area of P. biglobosa individuals varied as follows: Mokolo area (21.41 m 2 ha-1) and Roua-plateaux Zoulgo (20.06 m 2 ha-1). In these zones, big trees of P. biglobosa with large diameters were quite numerous. The average diameters were 79.14 ± 5.04 cm, and the average height was 13.60 ± 0.96 m. The structure of the distribution among the diameters generally was bell shaped, but the distributions varied in each zone. The greatest number of individuals was observed in the [50-70 cm] and [70-90 cm] diameter classes, with a remarkable increased presence of individuals in class [130-150 cm]. The scarcity of the individuals in the diameter range of 10 to 30 cm was noted in the various zones, with their entire absence in the Roua-Plateaux Zoulgo and Méri zones. The rate of regeneration of P. biglobosa was 13 %. This rate was very weak compared to the socioeconomic importance of this species. This regeneration rate will not ensure continued population strength of this multipurpose species. This species is proven of importance, but its capacity of regeneration was too low to ensure its sustainability. It becomes imperative to develop effective strategies for its regeneration and conservation.

Published online at www.m.elewa.org on 31 st October 2018 https://dx.doi.org/10.4314/jab.v130i1.10 RESUME Objectif : évaluer la structure écologique et la production de fruits de Haematostaphis barteri pour fournir les informations nécessaires à une meilleure gestion et conservation de l'espèce au Cameroun. Méthodologie et Résultats : Dans quatre sites, 48 parcelles d'un hectare ont servi pour des inventaires forestiers de Haematostaphis barteri et 120 arbres l'ont été pour quantifier la production. La distribution de diamètre montre une courbe en J renversé, caractéristique des populations jeunes. La densité varie de 13 à 17 individus/ha. La surface terrière varie de 0,28 à 0,49 m²/ha, le diamètre varie de 17,31 à 20,57 cm. Le nombre de fruits par panicule et par arbre varie de 15 à 28 et de 2346 à 7877 respectivement. L'analyse des paramètres dendrométriques et de production montre une différence significative (P < 0,001) entre populations. Conclusion et Application des résultats : L'environnement est le facteur qui distingue le mieux les différentes populations et explique mieux les variations observées entre elles en ce qui concerne leurs caractéristiques structurelles et de production. Cependant il serait nécessaire de ressortir l'impact de la surexploitation sur la distribution et la production dans les différents sites.

Prosopis africana is an important species with hard wood. Because of reason, this resource is very exploited by the local population for their daily survival threatening his durability. In order to know the importance of this plant in the peasant level, the present study was carried out in the Far-North, Cameroon, precisely in Holom soil. The objective of this study was to check off the different usages of P. Africana and to characterize the population of this species. The methodological approaches adopted to achieved this objective were the socio-economical investigation realized randomly close to 245 persons; the floristic inventory made on one area of 6.5 ha. The results show that, all parts of P. africana are important for the population. Branches (31 %) are used for fabrication of mortar, confection of shed, attic etc…leaves (16 %) are useful for cattle nutrition. Roots intervene in traditional pharmacopoeia at 5 % only. The wood of this species is very used as firewood (62 %). Globally, 38.46% of interviewee affirmed that the frequency of exploitation of this tree is very raised. According to dendrometrics parameters of P. africana, the results show a dominance of individuals with 5 to 10 m (45.56 %) of height, 20 to 60 cm (58.22%) of Diameter of the breast height, presenting bell distribution and a natural regeneration with height inferior or equal to 0,5 m (54,87 %) less represented. In front of the overexploitation of P. africana, the awareness of the population in the mode of effective management and the setup of rapid way of regeneration of this one are necessary to save the species for the interest of futures generations.