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La presente etude, realisee dans le Parc National du W, vise a contribuer a la connaissance de l’ecologie, de la frequence et de la periode d’apparition de Amanita subviscosa, une espece de champignon ectomycorhizienne, mal connue dudit parc. Pour ce faire, des investigations ont ete menees dans trois types de formations vegetales, au cours de la periode de juillet-septembre 2008-2016. Ainsi, l’espece est infeodee a la savane arboree, a la foret claire et a la galerie forestiere, aux alentours des pieds de Afzelia africana et Isoberlinia doka. Dans le premier biotope, sa frequence d’apparition est de 40%, alors que dans la foret claire et la galerie forestiere, sa frequence d’apparition est respectivement 33,33% et 26,67%. Dans ces trois (3) biotopes, A. subviscosa est plus abondante a partir du 20 juillet jusqu’en fin aout, en periodes des pluies regulieres. The present study, carried out in the W National Park, aims to contribute to the knowledge of the ecology, the frequency and the period of appearance of Amanita subviscosa, an ectomycorrhizal fungus species which it is little known from the above-mentioned park. To achieve this task, some investigations were carried out in three types of plant formations, during the period from July-September 2008-2012. This species is linked to the tree savannah, the open forest and the forest gallery, around Afzelia africana and Isoberlinia doka trees. In the first biotope, its frequency of occurrence is 40%, while in the open forest and gallery forest, their frequency of occurrence are 33.33% and 26.67% respectively. In these three biotopes, A. subviscosa is most abundant from the July the 20th until the end of August, during regular rain periods.

Field investigations have been carried out in the forest landscapes of the Ngaoundéré cliff and its outskirts, in the Vina Department of Cameroon. To learn more about the floristic richness and the chorologic position of the site of interest, an analysis of the flora, the autoecological and phytogeographic spectra of species has been undertaken. This analysis is based on floristic material from different surveys carried out in seven villages. On an area of 8.4 hectares prospected, through 84 phytosociological surveys, a floristic matrix of 87 species distributed in 46 genera and in 39 families was retained. Some of these species are of high ecological importance to the instarTerminalia laxiflora(16.58%),Isoberlinia doka(15.26%),Terminalia glaucescens(13.55%),Vitellaria paradoxa(10.17%),Parkia biglobosa(8.78%),Sarcocephalus latifolius(8.30%),Pterocarpus lucens(8.22%),Daniellia oliveri(7.92%).The families of the Fabaceae (64.83%), Combretaceae (43.18%), Euphorbiaceae (22.98%), Moraceae (16.35%), Rubiaceae (16.34%), Anacardiaceae (16.02%), Sapotaceae (10.17%), Myrtaceae (9.89%), Meliaceae (8.85%) and Annonaceae (7.51%) are the most diversified in cash. The ecological spectra highlight the high representativeness of microphanerophytes and ballochorous. On the phytogeographic level, the preponderance of multiregional species detected indicates the instability of forest landscapes in the study area. Moreover, the high rate of species with limited distribution in the African continent is an indication of disturbance and shows that the flora loses its specificity. All in all, this vegetation is in gradual degradation because of human activities.

The Mandara Mountain eco-region is one of the most important mountain areas of Cameroon. It is often considered as a refuge for several plant and wildlife species. This area is fragile and vulnerable, and faces severe threats from land use change, unsustainable exploitation of natural resources, desertification and climate change. Recent studies in sacred groves portrayed these land use types as indigenous strategies which can help to address these environmental problems. Understanding the plant diversity and carbon storage of these land use types in Mandara Mountain can be a good step towards their sustainable management for the delivery of diverse ecosystem services. In this perspective, we established a total of 10 nested circular plots of 1257 m2 each, in the sacred grove of the Mouhour village in Mandara Mountain, and all trees and shrubs with average diameter at breast height (dbh) ≥ 2.5 cm were counted. Tree biomass was estimated on the basis of DBH and understory biomass using destructive method. A total of 182 woody plants were measured, belonging to 21 species, 18 genera and 12 families. The richest family is Combretaceae with 5 species, followed by Caesalpiniaceae and Mimosaceae (3 species each). The analysis of species diversity indexes shows a relative important biodiversity and the vegetation structure showed a high occurrence of small-diameter of plant species. Mean aboveground carbon stock of 31.13 ± 10.8 tC/ha was obtained in the study area. Isoberlinia doka showed the greatest carbon stock (5.7 tC/ha) followed by Boswellia dalzielii (3.9 tC/ha), Acacia senegal (3.5 tC/ha), Anogeissus leiocarpus (3.3 tC/ha) and Terminalia laxiflora (3.1 tC/ha). These results suggest that the sacred groves of Cameroon dry lands need to be taken into account in national environment protection policies as an alternative to respond to international agreements related to biodiversity conservation, combatting desertification and climate change. DOI: http://dx.doi.org/10.3126/ije.v4i2.12659 International Journal of Environment Vol.4(2) 2015: 308-318

L’objectif de cette etude etait de determiner l’influence des activites anthropiques incontrolees ainsi que du type de vegetation sur la structure des peuplements de Isoberlinia spp.. Les donnees ont ete collectees dans 43 placeaux installes dans les forets claires et les savanes arborees/boisees situees dans la foret classee et hors foret classee. Les parametres consideres ont ete le diametre, la hauteur, la densite, la surface terriere et la valeur d’importance ecologique. Le test non-parametrique de Kruskal-Wallis et la distribution de Weibull ont permis respectivement de comparer les moyennes et d’apprecier la dynamique. Dans la foret classee, les valeurs moyennes du diametre, de la hauteur et de la surface terriere etaient plus elevees et differaient (p 0,05) entre les deux entites. La densite de regeneration est importante, mais peu s’affranchissent. Suivant le type de formation vegetale, les forets claires sont dominees par des individus de gros diametres et de grande taille. La structure de Isoberlinia spp . presente une allure en cloche avec le parametre de weibull c = 2,32, traduisant une distribution asymetrique positive avec une predominance d’individus de gros diametre. Les peuplements de Isoberlinia spp . sont mieux conserves dans la foret classee, notamment dans les forets claires. Cependant, la faible capacite de l’espece a assurer la succession des classes menace la survie de ces peuplements. La prise de mesures de gestion appropriees alors s’impose. © 2019 International Formulae Group. All rights reserved Mots cles: Degradation, peuplements, structure, foret classee de Koulbi, forets claires English Title: Effects of anthropogenic pressure on stands of Isoberlinia doka Craib and Stapf and Isoberlinia tomentosa (Harms) Craib and Stapf in the Sudanian zone of Burkina Faso English Abstract The objective of this study was to determine the influence of uncontrolled human activities and vegetation type on the stand structure of Isoberlinia spp . Data were collected in 43 plots installed in woodland, tree and wood savannah stands located inside the protected and unprotected areas. Parameters considered were stem diameter, tree height, stand density, basal area and importance value index. The non-parametric Kruskal-Wallis test was used to compare averages. The Weibull distribution was used to assess the structure dynamic of stands inside and outside the protected area. In the protected area, the mean values of diameter, height and basal area were significantly higher (p 0.05) between the groups. The density of the regeneration is quite important. But most of them (75%) remain in the height class] 0 to 0.5 m]. According to vegetation types, woodland are dominated by large individuals. The structure of Isoberlinia spp . has a bell shaped curve with the weibull parameter c = 2.32, reflecting a positive asymmetric distribution with a predominance of large diameter individuals. The stands of Isoberlinia spp . are better conserved in the classified forest, especially in open forests. The low regeneration capacity threatens the survival of these stands in the long term. So better management measures are therefore needed to halt the degradation process. © 2019 International Formulae Group. All rights reserved Keywords: Degradation stands structure, classified forest of Koulbi, woodland

Isoberlinia doka Craib & Stapf et Isoberlinia tomentosa (Harms) Craib & Stapf sont deux arbres originaires d’Afrique. Autrefois peu convoités, ils revêtent actuellement une utilité avérée pour les populations locales. Au Moyen-Bénin, l’intégration des savoirs traditionnels relatifs au genre Isoberlinia dans les stratégies de développement local demeure importante mais peu documentée. L’objectif de cette étude était d’évaluer, d’une part, les connaissances endogènes relatives aux utilisations des deux essences et, d’autre part, l’effet de cinq facteurs socioculturels ainsi que leurs interactions sur la valeur d’usage des deux essences dans le Moyen-Bénin. Des enquêtes ethnobotaniques ont été conduites auprès de 480 informateurs répartis dans huit groupes socioculturels. La fréquence relative de citation (FRC) et la valeur d’usage (VU) ont été calculées et analysées en utilisant respectivement une analyse en composantes principales (ACP) et des modèles linéaires généralisés (GLM) basés sur la distribution de Poisson. Les Mahi et Nago utilisent plus I. doka comme bois de charpente ; les Dendi et Holli utilisent plus I. tomentosa comme bois d’œuvre. Les modèles simples à un facteur montrent que, parmi les facteurs testés, le groupe socioculturel détermine les variations de l’usage des deux essences, et l’activité professionnelle influence aussi l’usage de I. tomentosa. L’évaluation de l’effet simultané des cinq facteurs sociaux et de leur interaction dans un même modèle multiple montre que les différences de la valeur d’usage de I. tomentosa entre les groupes socioculturels peuvent être amplifiées par l’activité professionnelle. Par ailleurs, pour I. doka, le modèle incluant uniquement le groupe socioculturel est celui le plus parcimonieux. Les politiques de gestion durable des deux essences devraient intégrer au premier plan les considérations socioculturelles, auxquelles s’ajoutent les appartenances professionnelles et, dans une moindre mesure, la taille du ménage pour I. tomentosa.

The Dahomey gap is a savanna region separating the West African rainforests to two regions. We set two sites in this woody savanna, at north and south regions in purpose to examine the differences in tree community properties between sites and among canopy-closure types, and to reveal the factors affecting the differences. Two sites are ca. 225 km distant from each other and have different rainfall patterns. Six 1-ha plots in each site were studied, which cover three types of canopy-closure (closed, semi-open and open). We recorded 3,720 trees that are equal to or more than 5 cm diameter at the breast height, consisted of 70 species belonging to 34 families. Most abundant three species, Isoberlinia doka, Vitellaria paradoxa and Pericopsis laxiflora appeared in both sites. The detrended correspondence analysis (DCA) based on species abundance divided 12 plots into groups of north and south sites along the first axis, whereas canopy-closure types were not associated with DCA axes. At any given total tree height, trees in the north site had slenderer stems with narrower crowns than those in the south site. The specific leaf area was smaller in the north site. Between-site differences in species abundance and allometry are possibly driven by rainfall variation.

A floristic and dendrometric analysis was carried out using 15 square plots of 1 ha each in the Bellefoungou forest reserve, located in the Sudano-Guinean zone of Benin. Species and diameter at breast height of trees were recorded. Multidimensional scaling and importance value index of species were used to identify vegetation types in the reserve: (1) Isoberlinia tomentosa-dominated vegetation type, (2) Isoberlinia doka and Burkea africana-dominated vegetation type and (3) Vitellaria paradoxa and Isoberlinia doka-dominated vegetation type. Significant differences were noted between the three vegetation types with respect to the basal area of trees. This varied from 8.55 m2/ha (vegetation type 3) to 13.36 m2/ha (vegetation type 2). The overall woody species richness was 57 species. The stem diameter structures of all three vegetation types showed an inverse “J” shape, suggesting that the study reserve has stable natural vegetation with relatively more young stems than large stems. Setting and impl...

This study concerns characteristics of forest gallery of Kossi River in municipalities of Dassa-Zoumé and Glazoué in the Department of Hills. The study of structure and floristic diversity of gallery forest of Kossi River was done by phytoecological method in 41 plots of 2,500 m² (50 m × 50 m) for study of plants groups and plots of 25 m² (5 m × 5 m) for régénération. In total, 82 species left in 68 genders and 28 families were identified. The analysis of the 41 plots by the Detrended Canonical Analysis (DCA) shown 03 plant groups such as Anogeissus leiocarpa and Daniellia oliveri group plant, Anogeissus leiocarpa and Isoberlinia doka group, and Cynometra megalophylla and Ceiba pentandra group. Specie richness of these plant groups varies from 31 to 41 species (dbh ≥ 10 cm). Families diversity is between 21 and 22 with predominance of Moraceae, LeguminosaeCaesalpinoideae and Leguminosae-Mimosoideae. Shannon diversity index varies from 2.4 to 3.1 bits and Pielou equitability from 0.5 to 0.6. Density varies from 129 to 233 stems / ha, basal area from 7.9 to 17.2 m² / ha and regeneration rate by group plants varies from 21.60 % to 42.96 %.

Objective: The objective of this study is to identify the plant species and to characterize the vegetation of the Ouoghi forest reserve in the commune of Savè (Center-Benin). Method and results: Floristic and forest inventories were carried out through 144 relevés in according to the Braun-Blanquet method. A total of 246 plant species were identified. They belong to 178 genera and 63 families. Multivariate analyzes with the Community Analysis Package (CAP) software made it possible to individualize 3 vegetation formations comprising 8 plant groups. This is the shrub savannah with Prosopis africana and Pennisetum polystachion, the tree savannah with Hymenocardia acida and Pennisetum polystachion, the tree savannah to Vitellaria paradoxa and Pennisetum polystachion, the tree savannah to Pterocarpus erinaceus and Hyptis suaveolens, the woodland savannah with Daniellia Oliveri and Chromolaena odorata, the woodland savannah at Isoberlinia doka and Pennisetum polystachion, the woodland savannah at Daniellia oliveri and Andropogon tectorum and the tree flood savannah to Daniellia oliveri and Leersia hexandra. The floristic and structural parameters change from one group to another. Thus, the specific richness varies from 49 to 153 species and the diversity of families is between 22 and 49 with a predominance of Leguminosae. The density varies from 95 to 275 stems / ha, basal area from 2.35 to 8.44 m² / ha. Conclusion and application of results: The study evaluated the floristic diversity of the Ouoghi reserve. In addition, it indicated the need for its integral protection for its dynamics towards dry dense forest vegetation. Sustainable management of this site needs implication of local population.

Protected areas constitute strategy for biodiversity conservation. Unfortunately, these sanctuaries of biodiversity are submitted to a high human pressure in Togo. This study carried out in the Aledjo protected area, aimed to make an analysis of various forms of human footprints and their impact on its plant resources. Methodological approach was based on forest inventory completed by inquiries. Ninety-four wooded species belonging to 35 families were counted. Floristic data analysis showed that seven species: Isoberlinia doka Craib & Stapf, Daniellia oliveri (Rolfe) Hutch. & Dalz., Berlinia grandiflora (Vahl) Hutch. & Dalz., Pterocarpus erinaceus Poir., Zanha golungensis Hiern, Khaya senegalensis (Desv.) A. Juss., Pentadesma butyracea Sabine was prominent. Five vegetation types were identified: riparian forests, dry forests, open forests, savanna woodlands, tree/shrub savannas with variable structural characteristics. The diversity indices in these plant communities are well significant and indicate a good distribution of species in the area. Several human activities such as fuel wood, fruits and medicinal plants gathering, carbonization, pasture were found within the protected area. Local authorities and associations are involved in the management of the protected area, but the participation of local populations needs to be improved. Resume Les aires protegees constituent une strategie de conservation de la biodiversite. Malheureusement, au Togo, ces sanctuaires de biodiversite sont soumis a de fortes pressions humaines. Cette etude, realisee dans l'aire protegee d'Aledjo, visait a faire une analyse des diverses formes d'empreintes humaines et de leurs impacts sur ses ressources vegetales. L'approche methodologique s'est basee sur un inventaire forestier, complete par des enquetes. Nous avons denombre 94 especes ligneuses, appartenant a 35 familles. L'analyse des donnees floristiques a mis en evidence sept especes dominantes, a savoir Isoberlinia doka Craib & Stapf, Daniellia oliveri (Rolfe) Hutch. & Dalz., Berlinia grandiflora (Vahl) Hutch. & Dalz., Pterocarpus erinaceus Poir., Zanha golungensis Hiern, Khaya senegalensis (Desv.) A. Juss. et Pentadesma butyracea Sabine. Nous avons identifie cinq types de vegetation: les forets galeries, les foret seches, les forets claires, les savanes boisees et des savanes arborees/arbustives avec des caracteristiques structurales variables. Les indices de diversite dans les communautes vegetales sont eleves et indiquent une bonne distribution des especes dans l'aire. On a releve dans l'aire protegee plusieurs activites humaines, comme la collecte de bois de feu, de fruits et de plantes medicinales, la carbonisation et le pâturage. Des autorites et des associations locales sont impliquees dans la gestion de l'aire protegee, la participation des populations locales etre amelioree.

The open Isoberlinia spp. woodlands found on slopes and valley floors in Togo's Sudanian region are subject to various pressures including clearance for crop-fields, cutting for timber or fuelwood and gathering of non-timber forest products. The resulting degradation is worsening poverty among the local people who depend on these forests. To support their sustainable management for the benefit of these local populations, the impacts of human pressures on the forest structure first need to be analysed. The forest inventories conducted covered 4 783 trees in 225 study plots. More than one hundred woody species were listed, belonging to 79 genera and 32 families. The most frequent were Isoberlinia doka, Pterocarpus erinaceus, Lannea acida, Isoberlinia tomentosa, Vitellaria paradoxa, Daniellia oliveri and Parkia biglobosa. The surveys identified four main parameters determining ecological gradients: moisture, topography, soil substrate and human influence. Nine woodland fades were identified: four open woodland types, three tree savannah types and two in fallow areas. Three structural components were determined by analysing tree diameter structure for the nine facies. Finally, relatively undisturbed natural forest areas with stable and continuously regenerating flora and regular forest structure were easily distinguished from degraded forest areas characterised by a lack of large trees and low regeneration potential. The human pressures exerted on these fragile woodland areas clearly suggest replanting in the degraded areas, using low-cost multiplication techniques, although raising awareness among the neighbouring populations about the need for conservation remains essential to ensure participatory management., Les forêts claires à Isoberlinia spp. du domaine soudanien du Togo, rencontrées aussi bien sur les versants que dans les plaines, subissent diverses pressions telles que les défrichements agricoles, l’exploitation du bois de service et de feu ou encore la collecte des produits forestiers non ligneux. Ces forêts ainsi dégradées accentuent la paupérisation des populations riveraines qui en dépendent. Afin de contribuer à leur gestion durable au profit de ces populations locales, il s’avère nécessaire d’analyser l’impact des pressions anthropiques sur la structure de ces forêts. Des inventaires forestiers y ont été conduits. Les travaux ont porté sur 4 783 arbres au sein de 225 placeaux de mesures. Plus de cent espèces ligneuses ont été inventoriées comprenant 79 genres et 32 familles, les plus fréquentes étant Isoberlinia doka, Pterocarpus erinaceus, Lannea acida, Isoberlinia tomentosa, Vitellaria paradoxa, Daniellia oliveri et Parkia biglobosa. Les relevés ont permis de déterminer quatre gradients écologiques majeurs : l’humidité, la topographie, le substrat édaphique et l’anthropisation. La classification a identifié neuf faciès forestiers dont quatre en forêts claires, trois en savanes boisées et deux au sein de jachères. En outre, trois composantes structurales ont été définies en analysant la structure diamétrique des neuf faciès. Enfin, il a été aisé de distinguer, d’une part, les forêts naturelles peu perturbées, présentant une stabilité floristique bénéficiant d’un flux de régénération continu, ainsi qu’une régularité de structure, et, d’autre part, les forêts dégradées qui se caractérisent par l’absence de tiges de grande taille et le faible potentiel de régénération. La pression humaine qui s’exerce sur ces forêts fragiles ne peut qu’inciter à reboiser les espaces dégradés, en mettant à profit les techniques de multiplication végétative à faible coût. Reste surtout à atteindre une prise de conscience de la part des populations riveraines pour ce qui a trait à la conservation de ces milieux, et aboutir à une gestion participative., Los bosques abiertos de Isoberlinia spp . del dominio climático sudanés de Togo, ubica- dos tanto en pendientes como en llanuras, sufren diversas presiones como desmontes para uso agrícola, extracción de madera o leña y también la recolección de productos forestales no maderables. Estos bosques así degradados acentúan la pauperización de las poblaciones colindantes que depen- den de ellos. Para contribuir a un manejo sostenible que beneficie a la población local, es necesario analizar el impacto de las presiones antrópicas en la estructura de dichos bosques. Se realizaron inventarios forestales y los estudios se centraron en 4 783 árboles en 225 parcelas de medición. Se han inventariado más de 100 especies leñosas que incluyen 79 géneros y 32 fami- lias, las más frecuentes son Isoberlinia doka, Pterocarpus erinaceus, Lannea acida, Isoberlinia tomentosa, Vitellaria paradoxa, Daniellia oliveri y Parkia biglobosa . Las observaciones permitieron determinar cua- tro gradientes ecológicos principales: humedad, topografía, sustrato edáfico y antropización. La clasificación ha identifi- cado nueve facies forestales: cuatro en bos- ques abiertos, tres en sabanas arboladas y dos en barbechos. Además, al analizar la estructura diamétrica de las nueve facies, se definieron tres componentes estructurales. Por último, fue fácil distinguir, por un lado, los bosques naturales poco alterados y que presentan una estabilidad florística que se beneficia de un flujo de regeneración conti- nuo y de regularidad estructural y, por otro lado, los bosques degradados que se carac- terizan por ausencia de tallos de gran tamaño y su bajo potencial de regeneración. La presión humana a la que se ven someti- dos estos bosques frágiles sólo puede servir de estímulo para la reforestación de los espacios degradados aprovechando las técnicas de multiplicación vegetativa de bajo costo. Sobre todo hace falta lograr la concienciación por parte de las poblaciones colindantes en todo lo referido a la conser- vación de estos entornos y conseguir un manejo participativo.

The biological contents of the March 2010 hazy dust in Nigeria deserve verification due to the attendant panic it brought to the public. 3 g of dust deposited on the car bonnet of one of the authors was treated chemo-palynologically and microscopic study of the residue was carried out. The study reveals that the dust was rich in pollen grains, fungal spores and hyphae. No pteridophyte spore was recovered. High proportion of diatoms almost doubling that of the sporomorphs was recorded. Savanna and derived savanna pollen grains and the Sahara desert freshwater diatoms recovered indicate that the dust was still the harmattan borne by the Northeast Trade winds though coming heavily and lately in March instead of the traditional January. This indicates a delay in the northward movement of the Inter Tropical Discontinuity (ITD) with the consequential abnormal hazy atmosphere. Some typical Sudan and Sahel vegetations’ pollen were not recovered inspite of the dust crossing over them, perhaps due to being dropped along the way or March not being their flowering periods. Pollen of Vitex cf. doniana dominates the palynoflora along with Isoberlinia doka which might be candidate culprits for clinical conditions in the experimental area. Key words: Saharan dust, palynoflora, diatoms, intertropical discontinuity.

This study was carried out to examine fuelwood sellers' perception of environmental issues in Borgu Local Government Area of Niger State, Nigeria. A total of 120 fuelwood sellers supplied primary data on their socio-economic characteristics, sources of information on environmental issues, tree species commanding high patronage and perception of environmental issues. More than half of the respondents fall within the age of 31-40 years (53%), 63.3% were females, 87.5% were married and 61% had no formal education while 51% obtained information on environmental issues from radio and television. The results further indicated that Detarium microcarpum, Vitellaria paradoxa, Crossopteryx febrifuga, Pterocarpus erinaceus, Combretum nigricans and Isoberlinia doka were the tree species commanding high patronage in the study area. Also, the fuelwood sellers have adequate information on environmental issues not only in their locality but globally. The study concluded that since they are fully aware of the consequences of their activities on the environment, they should be involved in the design of policies aimed at reducing the rate of extraction of fuelwood in the area. Keywords : Perception, fuelwood, fuelwood sellers, environmental issues, tree species Journal of Environmental Extension Vol. 7 2008: pp. 43-47