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There is a rising demand for natural fiber reinforced polystyrene composite materials because of the toxicity associated with mineral-based composites and the rising environmental problems associated with the proliferation of polystyrene waste. This study describes the development and characterization of wood dust (isoberlinia doka) reinforced polystyrene composites by hand lay–up method at moderate pressure and examining the influence of filler concentration (15, 30 and 45%), filler size (149, 250 and 841 µm) and NaOH concentration (2, 4 and 6%) on the mechanical behaviors of the composite. Also, the influence of filler concentration on the thermal properties of the composite was investigated. The composites produced were characterized to determine their mechanical, thermal and microstructural properties. Results from the study revealed that the mechanical properties were greatly improved at 30% filler concentration, 841 µm filler size and 4% NaOH concentration process condition. Also, there was a significant improvement in the thermal property of the composite at 30% filler, while the microstructural study gave a hint of good interaction between the filler and the polymer matrix.

In this study, the water absorption, thermal conductivity and microstructural properties of Isoberlinia doka wood sawdust polystyrene composite, synthesised by the hand layup method, were investigated as a function of filler content. It was observed that the thermal conductivity increased with increase in the fibre loading. The thermal conductivity value obtained for the synthesised composite samples was an average of 0.147 Wm−1 k−1. The composites absorbed water until equilibrium was achieved on the 9th day. The maximum water absorbed at equilibrium for the composite with filler concentration of 10, 20, 30 and 40 wt% was 36.46, 40.34, 57.53, 128.65 wt%, respectively. The mass transfer kinetics revealed that water sorption rate increased at higher filler composition due to the increased interstitial pores and gaps that are exacerbated by increased fibre loading. The mass transfer kinetic constants for the composite with filler concentration of 10, 20, 30 and 40 wt% were 0.738, 0.661, 0.996 and 1.155 day−1. Microstructural analysis revealed that the dispersion of wood sawdust particles improved as the fibre loading increased.

This study presents a development of strength classes for Vitex doniana, Diospyros mespliformis, Parkia biglobosa and Isoberlinia doka, northern Nigeria timber species in accordance with BS 5268-2 (2002) and NCP 2 (1973). The specimens for the experimental measurements were obtained from timber-sheds in Zaria, Kaduna - Northern part of Nigeria. The laboratory experiments were conducted to determine the physical and mechanical properties of the selected timber species. The specimens were prepared in accordance with BS 373 for small clear specimens for the determination of physical and mechanical properties. Flexural strength properties were determined using three point bending test. Adjustment was made on the mechanical properties at moisture content of 12% and 18% in conformity with BS 5268-2 (2002) and NCP2 (1973) respectively. The laboratory data were analyzed using data analysis tool pack in Microsoft excel 2019 to generate the mean, coefficients of variation and theoretical distribution models which form the uncertainty models. Basic and grade stresses were also computed using experimental failure stresses. The selected timber species were then classified using the grade bending stress, density and mean modulus of elasticity obtained. Vitex doniana, Diospyros mespliformis, Parkia biglobosa and Isoberlinia doka were assigned to strength classes D30, D40, C40 and D30 in accordance with BS 5268-2 (2002) respectively. Similarly, in accordance with the NCP 2 (1973), these species belong to N4, N3, N4 and N3 respectively. The results obtained show that Vitex doniana, Diospyros mespliformis and Isoberlinia doka are hardwoods whereas, only Parkia biglobosa is a softwood species.

West African Sudanian savanna ecosystems greatly contribute to local peoples’ livelihoods and climate change mitigation. Yet, the contribution of these ecosystems to carbon storage remains poorly documented due to the lack of accurate biomass predictive tools. Therefore, biomass allometric models developed at both the species-level and site-level may greatly improve carbon stock estimation. In this study, we developed allometric models for estimating aboveground biomass (AGB) at the tree component-, species- and site-levels in Burkina Faso. Five woody species with high socio-economic significance (Anogeissus leiocarpa, Combretum nigricans, Isoberlinia doka, Mitragyna inermis and Pterocarpus erinaceus) were selected at two forest sites based on their dominance in the savanna ecosystem. A total of 150 trees (30 trees per dominant species) spanning a wide range of diameter at breast height (DBH) were destructively sampled. Models to predict tree component biomass at the species-level were independently built with the Ordinary Least Squares (OLS) technique. Allometric models to predict tree total aboveground biomass (TAGB) for each species and all species were developed using both the OLS technique and the Seemingly Unrelated Regression (SUR) method. Biomass estimates were regressed with DBH as a single predictor, DBH and height (H) as interacted variables, and DBH, H and wood density (ρ) as three independent-input variables. The performance of the validated allometric models were compared with the generalized pantropical equation model for African tropical forests (Chave et al., 2014). The findings revealed that biomass predictors varied between the five species. The goodness-of-fit statistics revealed that both the OLS and SUR methods provide accurate biomass allometric equations, with the SUR method being the most accurate. The developed allometric models provide more accurate estimation of AGB than the pantropical model. Therefore, we recommend the use of these local models to improve the quantification of AGB and carbon stocks in Sudanian savanna ecosystems. Furthermore, the established species-specific and mixed-species allometric equations may constitute a useful tool for the monitoring, reporting and verification of carbon stocks within the REDD+ framework in Burkina Faso.

Burkina Faso has abundant wild mushrooms, but very few inventories have been carried out to record these species. The shortage of taxonomic studies in Burkina Faso on wild mushroom species limits their knowledge. Three species of the genus Amanita from Burkina Faso are reported and fully described in this paper. They are Amanita pulverulenta Beeli, Amanita citrina (Schaeffer) Persoon and Amanita odorata Beeli. All the three species were collected in the classified forest of Niangoloko, preciously in the mosaic gallery forests dominated by Berlinia grandiflora (Vahl) Hutch. & Dalziel and Isoberlinia doka Craib & Stapf (Caesalpiniaceae) and are assumed to be ectomycorrhizal. Key words: Fungi, gallery forest, Niangoloko, Burkina Faso.

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.

Isoberlinia dokais dominant specie in the savannah of West Africa belonging to the family Fabaceae. It is used in traditional medicine for treatment of muscular – skeletal system disorders, Jaundice scorpion bites, Convulsion, diabetes, ulcer, wounds and cough. The objectives of the study are to determine the pharmacognostic and antioxidant activity ofIsoberlinia dokaleaves. Three extracts ofIsoberlinia dokaleaves were obtained by sequential maceration using n-hexane, ethyl acetate and methanol The extracts were screened qualitatively for the presence of saponins, carbohydrates, tannins, flavonoids, cardiac glycosides, anthraquinones and alkaloids using standard procedures. Thin layer chromatography was carried out to determine the separation profile of various extracts. Antioxidant activity of the methanol leaves extract ofIsoberlinia dokawas determined using 1, 1-diphenyl-2-picrylhydrazyl radical (DPPH) Assay. The phytochemical screening of the methanol extract revealed the presence of alkaloids, flavonoids, tannins, cardiac glycosides and saponins. The methanol leaves extract ofIsoberlinia dokademonstrated strong radical scavenging activity and reducing power ability with concentration dependent responses. The results of this study suggest that the plant can serve as a good source of antioxidant which can aid in the management of diseases associated with oxidative stress.

The dynamic and productivity of natural reserves in Benin were assessed in the Mounts Kouffe and Wari Maro forest reserves on the basis of sixty circular permanents plots of 1000 m2 size each installed in 2006. The factorial correspondences analysis of the based on a matrix of 60 records and 81species. Four different plants community were discriminated: - dry woodland of Diospyros mespiliformis and Anogeissus leiocarpa - woodland of Pterocarpus erinaceus and Isoberlinia doka - Wooded savanna of Vitellaria paradoxa and Burkea africana - Shrub savanna of Vitellaria paradoxa ans Isoberlinia doka The specific richness of individualized plant communities varies between 42 and 75 species. The Shannon index values calculated (dbh≥10cm) ranged between 1.25 and 4.66 bits; those of Pielou evenness ranged between 0.24 and 0.87. The diameter size classes distribution is best adjusted to Weibul three parameter function and showed a left skewed distribution. Trees basal area decreased by 0.80 m²/ha/year for the dry woodland and 0.25 m²/ha/year for the woodland while the one of wooded and shrub savanna increased by 0.50 m²/ha/year. The density of trees decreased by 120 trees/ha for dry woodland and by 108 trees/ha for woodland over the last five years. The diameter of individuals of average basal area has increased by 2.1 cm for dry woodland. 3.95cm for woodland. 2.8cm for Wooded savanna and 3.09cm for shrub savanna. The minimum exploitable diameter (MED) of 45cm allowed for 50% of Anogeissus leiocarpa and Isoberlinia doka basal area reconstitution while this MED allowed for 75% of Diospyros mespiliformis reconstitution.

Many scientific studies confirmed that plants have an important ecological role maintaining the productivity of the environment and regulating the global climate. In order to valorize the wild phytogenetic resources for the efficient in situconservation and sustainable use in Sudano-zambezian region, a study was carried out in Sudanian domainprovidingquantitative informations on the community structure and natural regeneration status of woody plant species.The study site is the eastern part of National Park of Sena Oura in Chad. Adults plants (trees and shrubs) were systematically collected in 10 linear transects (20 m x 1000 m). Juvenile plants (saplings and seedlings) weresystematically collected within 40 plots (20 m × 20 m). These plots were randomly stablished in the transects, at a rate of four plots per transect.In total, 84 adults plants species grouped in 58 genera and 29 families and 66 juvenile plants species grouped in 45 genera and 27 families were inventoried. Bell andreverse J-shaped patterns of selected woody species were identified.The stand regeneration status wasgood.The stand regeneration rate were SRR = 52.29% and Hymenocardia acida (SIR = 17.95%), Combretum collinum (SIR = 14.12%), Annona Senegalensis (SIR = 6.67%) and Isoberlinia doka (SIR = 6.22%) had the most important specific index of regeneration. The specific structures showed that the structure of the total stand is the result of the dynamics of all species and their interactions.The global stand regeneration status was good.The obtained results provided quantitative informations on the community structure and natural regeneration status of woody plant species for the efficient conservation and sustainable use.

The key role of ectomycorrhizal (EcM) fungi in ecosystems functioning has been demonstrated worldwide. However, their diversity, spatial distribution, fruiting phenology and production as influenced by climatic parameters variability remain poorly understood in tropical African forests. Weekly surveys were conducted from April to early October 2014 at the Comoe National Park (CNP), Cote d’Ivoire (West Africa) in 09 permanent plots established in Isoberlinia doka (IW), Uapaca togoensis (UW) and Mixed (MW) woodlands. Non metric multidimensional scaling (NMDS) of EcM fungi abundance was run to assess the influence of environment tal parameters on fungi distribution using the package VEGAN. Hierarchical clustering based on dissimilarity and indicator species analysis were run to characterize fungi communities. Analyses were computed with the statistical program R. A total of 123 EcM fungi species belonging to 23 genera and 09 families were collected at CNP. Simpson diversity (1-D) and evenness were 0.97 and 0.54, 0.97 and 0.61, 0.96 and 0.52 for IW, MW and UW respectively. Yet, weekly-based species accumulation curves did not reach an asymptote. Stem density of U. togoensis Pax (UTDen) and I. doka Craib & Stapf were the most important tree parameters influencing EcM fungi distribution (respectively r2 = 0.92 / p-value = 0.002 and r2 = 0.83 / p-value = 0.018). Two sites groups were distinguished and four indicators species were identified. Key words: EcM fungi, fruit bodies, diversity, indicator species.

Isoberlinia doka sawdust; an abundant waste material was pre-treated using FeCl3, HCl, NaOH, sequential HCl and NaOH treatments at 121 °C for 15 min to mitigate the challenges of its utilisation as a carbon source for bioethanol production. The effects of these treatments on the biomass were evaluated using Fourier transform infrared (FTIR) spectroscopy and gravimetric methods. The capability of the pre-treated residue to produce fermentable sugars and bioethanol were also assessed. The treated biomass were saccharified using cellulase mix from Aspergillus niger and Trichoderma reesi and fermented using Saccharomyces cerevisiae. The result shows that the chemical treatments significantly (p

Studies on the performance of Cajanus cajan and Sesbania sesban as cooking fuel was carried out. The germination rate was monitored from outset of the cotyledon till maturity within six months and the biomass was compared with Isoberlinia doka. Seedlings were established in the field in the fourth week on a single row per ridge with an interval of 30 cm.The growth rate was monitored in the field and the length of the stem, length and width of the leaf was taken. The stalks of Cajanus cajan became wood, the biomass was checked with Isoberlinia doka which is a major fire wood used by the people in Samaru, Zaria. It was observed that Cajanus cajan boiled 5000 ml of water within 20 minutes, 16 seconds while it took Isoberlinia doka 17 minutes, 20 seconds to boil the same volume of water.

Two woody species of different origins were subjected to Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis, and analytical pyrolysis gas chromatography/mass spectrometry (Py-GC/MS). Flynn-Wall-Ozawa, a model-free technique, was adopted for the decomposition kinetic study of Isoberlinia doka (ID) and Pinus ponderosa (PP). FTIR spectroscopy was employed to determine the level of cellulose crystallinity in the samples under investigation using the total crystallinity and lateral order indices methods. The apparent activation energy appeared as a function of conversion with significant influence from biomass diversity. The apparent activation energy recorded values of 202 to 365 kJ mol−1 for ID and 205 to 583 kJ mol−1 for PP. Thus, biomass decomposition kinetics is better modeled as a multi-step reaction mechanism. The analytical Py-GC/MS showed the presence of acids, sugars, and phenolic compounds in significant proportions for the two biomass samples. There were marked distinctions in both the quantity and the individual compounds detected in the biomass samples that were investigated.

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

Average population growth in the African Sudanian belt is 3 % per year. This leads to a significant increase in cultivated areas at the expense of fallows and forests. For centuries, rural populations have been practicing agroforestry dominated by Vitellaria paradoxa parklands. We wanted to know whether agroforestry can improve local rainfall recycling as well as forest. We compared transpiration and its seasonal variations between Vitellaria paradoxa, the dominant species in fallows, and Isoberlinia doka, the dominant species in dry forests in the Sudanian belt. The fallow and dry forest we studied are located in northwestern Benin, where average annual rainfall is 1200 mm. Sap flow density (SFD) was measured by transient thermal dissipation, from which tree transpiration was deduced. Transpiration of five trees per species was estimated by taking into account the radial profile of SFD. The effect of the species and of the season on transpiration was tested with a generalized linear mixed model. Over the three-year study period, daily transpiration of the agroforestry trees, V. paradoxa (diameters 8-38 cm) ranged between 4.4 and 26.8 L day(-1) while that of the forest trees, I. doka, (diameters 20-38 cm) ranged from 9.8 to 92.6 L day(-1). Daily transpiration of V. paradoxa was significantly lower (15 %) in the dry season than in the rainy season, whereas daily transpiration by I. doka was significantly higher (13 %) in the dry season than in the rainy season. Our results indicate that the woody cover of agroforestry systems is less efficient in recycling local rainfall than forest cover, not only due to lower tree density but also to species composition.

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...

Abstract The diet of the critically endangered Western giant eland (Tragelaphus derbianus derbianus Gray, 1847) has never been studied. We studied the food preferences of a Western giant eland group translocated from its native Sudanian habitat to a wildlife reserve in a Sahelian area in relation to the abundance of food in the new habitat. The study generated the first qualitative and quantitative data on this eland subspecies' diet. The translocated group fed only on 33 different plant species available in its new habitat. Isoberlinia doka, and Julbernadia sp., two species eaten by the other eland subspecies did not occur here. The food preference for most ligneous species did correspond to their high availability in the translocation area (like Acacia seyal, 32.56% versus 28.26% abundance in the new habitat, Acacia ataxacantha, 19.7% versus 17.03%, and Azadirachta indica, 7.11% versus 4.71%; only Grewia bicolor, 7.48% versus 10.14% did not). In contrast, the food preference for many herbaceous species did not, as some were preferred (like Merremia pentaphylla, 35.41% versus 11.01%, and Peristrophe bicalyculata, 2.58% versus 0.00%), and others avoided (like Corchorus tridens, 1.72% versus 2.20%, Cucumis melo, 0.43% versus 5.73%, and Abutilon ramosum, 0.21% versus 7.05%). The most eaten Cassia tora (42.7%) was also the most abundant (36.56%). Our data will provide conservation managers with information on how to protect the species' natural environment and to make appropriate management decisions with respect to the proclamation of protected areas or the identification of core zones, mainly for future (re)introduction of satellite populations.

This study has been designed to contribute to search alternative solutions based on plant extracts against phytopatogenic fungi. It aims to test the efficacy of ethanolic extract (70%) of Isoberlinia doka trunk bark on the mycelial growth of eight phytopagenic fungi species and on maize and cowpea seedlings germination and growth. The results showed that the ethanolic extract inhibits mycelial growth. This extract has showed an interesting efficiency on three fungi such as Colletotrichum dematium, Curvularia lunata and Fusarium verticilloides. Among these fungi, Curvularia lunata was the most sensitive with a rate of inhibition of mycelial growth of 52.35% after four days incubation at 10 mg / ml. After seven days incubation, the extract was more effective in reducing Fusarium verticilloides mycelial growth with 50,70% inhibition rate at the same concentration. After the phytotoxicity tests, it was found that this extract had no phytotoxic effect on the germination and growth of maize seedlings while it reduced significantly seed germination and cowpea seedling growth. The ethanolic extract of I. doka bark has antifungal properties and did not inhibited maize growth parameters. It could be used in maize seed treatment. Investigations could also be made into the herbicidal properties of some invasive legumes close to cowpea.

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 %.

In Africa, little is known about how the vascular anatomy of medicinal tree species is influenced by bark harvesting, and the ability of species to react against debarking needs to be better understood. This study aims to evaluate the temporal and spatial impact of bark harvesting on wood anatomy and to determine the extent to which a tree’s ability to close the wound after bark harvesting is affected by anatomical changes in the wood. We harvested bark from ten medicinal tree species located in an Isoberlinia doka woodland in Central Benin. Two years after debarking, the wound closure was measured and one tree per species was cut at the wound level to collect a stem disc. On the cross section of each disc, vessel features (area, density and specific conductive area) were measured in the radial direction (before and after wounding) and on three locations around the disc surface. We found that during early wound healing, all species produced vessels with a smaller area than in unaffected wood and this significantly decreased the specific conductive area in eight of the investigated species. However, after 2 years, only six trees had restored their specific conductive area. In addition, a significant positive correlation (r = 0.64, P < 0.005) confirmed the relationship between the specific conductive area and tissue production to close the wound and delineated the study group into two groups of trees. Therefore, we concluded that vessels appeared to be very good anatomical indicators of the tree’s reactions to debarking.

The inhibitory effect of water extract of seed, leaf and bark of five plants, viz., Tamarindus indica, Cassia siamea, Isoberlinia doka, Dolnix regia and Cassia sieberiana was evaluated on larval hatch of Meloidogyne incognita in the laboratory. All the plant parts inhibited larval hatch of M. incoginta Percentage inhibition was higher in the seeds followed by the leaves and bark. Degree of inhibition observed, was directly related to the concentration of the extract. The standard suspensions inhibited hatching by about 97% while dilutions of S/100 inhibited larval hatch by 3%. Nematicidal activity of the plant parts of the five plants showed that C. siamea was the most effective followed by C. sieberiana, I. doka, T. indica and D. regia.

The Sb, Cr, Ni, As, Pb and Cu contents in leaves of Dichrostachys cinerea, Ficus platyphylla, Isoberlinia doka and Securiniga virosa growing around the Kaduna Refinery and Petrochemical Complex (KRPC) were compared with heavy metal contents of the same species growing in a relatively “clean” environment, during the rainy and dry seasons of 2001. Concentrations of Cr, Ni, As and Pb in the leaves of the plant species monitored were significantly lower during the dry season than during the rainy season, particularly in the polluted site (P < 0.05). The concentrations Sb and Cu were lower only in F. platyphylla and S. virosa. Patterns of accumulation of individual heavy metals were variable. All four species of plants accumulated Pb to a higher degree (P < 0.05), than Cr and Ni, which had accumulation patterns similar, and higher than that of As. Arsenic was the least (P < 0.05) accumulated. Accumulation of Cu was different to other metals, being higher than Pb, Cr, Ni, and As (P < 0.05), and second only to Sb, which was hyper-accumulated in all four plants species. Heavy metal contents of the four species varied between rainy and dry seasons. The differences in metal contents observed between seasons, could be linked to relative availability of cations to plants as influenced by soil moisture content. Variations in pattern of accumulation of individual metals, could be related to the genetically induced capacity of plants to alleviate the toxic effects of heavy metals through mechanisms, which include binding metals to peptides and organic acids, formation of phytochelatins, cellular adaptations, efflux pumping systems and other mechanisms.

Inter-ring variations in stable-carbon isotope composition of cellulose in Daniella oliveri , Isoberlinia doka , and Tamarindus indica stumps were analyzed for nine trees in the Soudan-Sahel zone of West Africa. This pioneer isotopic study is a contribution to on-going efforts to evaluate the feasibility of extracting proxy climatic records from tree-rings in this area. Our aim is to investigate trends in individual floating δ 13 C time series to assess if patterns in variability within and between rings are consistent with those in other climatically sensitive tree-ring δ 13 C series. Samples were collected primarily from tree stumps but kill dates were unknown. Tree age was estimated from stump condition and shoot regrowth. This approach, combined with low sample replication, hindered the establishment of absolute dates. Nevertheless, δ 13 C and discrimination (Δ 13 C), absolute values and variability in the time series are similar to those often seen in tree-rings. Average δ 13 C values for individual series range from −25.90‰ to −23.72‰ and average Δ 13 C values from 16.56‰ to 18.99‰. It is well known that seasonal rainfall is inversely related to the δ 13 C in growth-season-dry environments and positively covaries with Δ. We investigate the possibility of using this relationship to temporally anchor the time series and to identify missing and false rings in wood segments with indistinct growth. The variability in these time series is consistent with expected patterns and shows promise for facilitating the development of stable carbon isotope tree-ring chronologies for West Africa.

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.

Au cours de prospections dans les formations forestieres du Sud et de l’Est du Burkina Faso, des champignons ectomycorhiziens du genre Scleroderma ont ete recoltes sous quatre Caesalpinioideae, Afzelia africana Sm., Isoberlinia doka Craib. & St apf., I. dalziellii Craib. & Stapf, et Berlinia grandiflora (Vahl) Hutch.; un Dipterocarpaceae, Monotes kerstingii Gilg. et deux Phyllanthaceae, Uapaca guineensis Mull. & Arg. et U. somon Aubr. & Lean. La description morphologique des carpophores et des spores de ces champignons a permis d’identifier deux especes definies (Scleroderma dictyosporum Pat et S. verrucosum Pers.) et quatre especes morphologiques non determinees (Scleroderma sp1, Scleroderma sp2, Scleroderma sp3 et Scleroderma sp4). Cependant, le sequencage de l’ITS (Espacer Interne Transcrit) et l’analyse phylogenetique de certains isolats (donnees non presentees) revelent plutot trois groupes d’especes morphologiques, S. verrucosum, S. dictyosporum, et Scleroderma sp2, suggerant que les especes du genre Scleroderma peuvent presenter diverses morphologies. Des isolements ont permis de mettre en culture 22 isolats, dont au moins un isolat par espece. L’etude de l’aptitude mycorhizogene de quelques isolats a montre que les Sclerodermes sont peu specifiques avec un large spectre d’hote, et seraient donc des candidats indiques pour la mise en place de programme de mycorhization controlee en Afrique tropicale seche. Mots-cles : Ectomycorhizes, Scleroderma, Morphologie, Burkina Faso. During prospectings in the forests vegetation of the South and East of Burkina Faso, the ectomycorrhizal fungi of the genus S cleroderma were collected under four Caesalpinioideae, Afzelia africana Sm ., Isoberlinia doka Craib. and Stapf ., I. dalziellii Craib. and Stapf, and Berlinia grandiflora (Vahl) Hutch.; one Dipterocarpaceae, Monotes kerstingii Gilg. and two Phyllanthaceae, Uapaca guineensis Mull. and Arg. and U. somon Aubr. and Lean. The morphological description of sporocarps and spores of these fungi allowed identifying two defined species ( Scleroderma dictyosporum Pat. and S. verrucosum Pers.) and four morphological species not described (Scleroderma sp1, Scleroderma sp2, Scleroderma sp3 and Scleroderma sp4). However, the sequencing of the ITS (Internal Transcribed Spacer) region of some isolates (data not presented) reveal rather 3 groups of morphological species; S. verrucosum, S. dictyosporum and Scleroderma sp2 , suggesting that the species of the genus Scleroderma can present diverse morphologies. Twenty-two (22) isolates are maintained in pur culture with at least an isolate by specie. Survey of ectomycorrhizal status of some isolates showed that Scleroderma are less specific with a broad host range and would thus be candidates indicated for the implementation of controlled mycorhization program in dry tropical Africa.

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

The inhibitory effects of Momordica charantia linn, Isoberlinia doka, Terminalia avicennioides, Tamarindus indica and Crotalaria retusa L aqueous leaves extracts on Opisthacanthus capensis (Black creeping scorpion) venom phospholipase A2 (PLA2 ) activity was investigated. The enzyme from O. capensis venom had a pH and temperature optima of 5 and 60˚C respectively with an activation energy of 5.20 Kcal/mol. Different concentrations (4mg, 6mg and 8mg/ml) of Isoberlinia doka and Momordica charantia Linn inhibited the activity of O capensis venom PLA2 in vitro displaying an uncompetitive inhibition pattern with a decrease in the computed index of efficiency (Kcat). Different concentrations (4mg, 6mg and 8mg/ml) of Terminalia avicennioides, Tamarindus indica and Crotalaria retusa L also inhibited O. capensis venom PLA2 activity in vitro but the inhibition pattern was competitive inhibition with Kcat remaining unchanged. This study reveals that the use of these plants by herbalists in northern Nigeria in the treatment of scorpion bites could be justifiable.

1. Primary fly-belts round Makongo consisted of three different vegetational communities: a Cynometra-Vitex association along the main length of the Makongo river, on a clay soil; a Ficus congensis association along the river close to the town, on a sandy soil; and Isoberlinia doka woodland on moist sandy soil north-west and south of Makongo.2. Secondary fly-belts of less dense vegetation occur in the orchard bush savannah round Makongo, and these are not colonised until the commencement of the rainy season.3. Glossina tachinoides and G. palpalis both occurred in the riverside communities, and G. palpalis alone in the Isoberlinia woodland.4. Along the river G. palpalis outnumbered G. tachinoides by 3:1 in the dry season. At the commencement of the rains G. tachinoides increased more quickly than G. palpalis, bringing their numbers very nearly equal, but at the end of the rains there was a decrease in G. tachinoides which restored the original proportion.5. G. morsitans had been found at Makongo formerly but was not met with at the time of this investigation, its absence being due to the disappearance of the larger antelope from the neighbourhood.6. Smaller game animals, small mammals and reptiles afforded an adequate food supply for tsetse in the fly-belts, and also passing herds of cattle, as well as natives from the village and travellers.7. The distribution of G. palpalis within the fly-belts was markedly influenced by the proximity of a cattle road along which herds of cattle passed almost daily, and by village water-holes.8. During the dry season the primary foci were always found to be the places of greatest relative humidity, and the fly does not tend to move out of these until the general atmospheric humidity has reached a certain fairly high degree.9. In clearing the fly-belts the removal of all primary foci within a quarter of a mile of the town and of thick bush within 100 yards of water-holes was undertaken. The work lasted from the beginning of February to the end of March 1931.10. The effect of clearing the Isoberlinia doka woodland was to banish G. palpalis completely, and it never returned to these clearings.11. On clearing the riverside Ficus congensis fly-belt, G. tachinoides was practically eliminated for the first three months, but reappeared in the clearings in June when there was a general increase and up-stream migration of this fly. G. palpalis remained in this clearing in fluctuating numbers up to June, when observations were suspended.12. 565 marked tsetse were liberated in the fly-belts immediately previous to clearing. Of G. palpalis 12·7% were recaptured in the clearings and 11% outside the clearings. Of G. tachinoides 5·5% were recaptured in the clearings and 6·8% outside.