Elvire Hortense BIYE

Ecological Restoration of Degraded Concrete Waste Zones at the Nachtigal Dam Construction Site (Cameroon): A Methodological Approach for Plant Regeneration Dynamics

Elvire Hortense Biyé, CHRISTIAN DJIMARABEYE, ATHINA ARELA MADELEINE MENYE

Cameroon Journal of Biological and Biochemical Sciences

The construction of large hydroelectric infrastructure often leads to significant soil degradation, particularly through the disposal of inert waste. At the Nachtigal Dam construction site in Cameroon, two concrete waste disposal sites in zones A and B were identified for ecological rehabilitation. In this study, we assessed the effectiveness of a three-layered soil remediation technique on the growth of 1,046 plants, selected based on both a survey conducted at the local community on products most commonly used and on an ecological assessment of the surrounding area, across a total area of 24,657.72 m², i.e. 8924.72m2 in zone A and 15733m2 in zone B. A mixed planting strategy incorporating 40% species producing non-timber forest products (NTFPs) and 60% woody species has been implemented to promote ecological functionality and socio-economic benefits. Post-planting monitoring through observation and counting revealed an overall survival of approximately 85%, despite localized erosion and varying survival rates within and between species. Thus, the rehabilitated areas exhibit strong regeneration potential, indicating that engineered soil profiles combined with structured planting of mixed species can effectively restore degraded concrete waste areas. This study sheds light on assisted regeneration practices relevant to large infrastructure projects in tropical forest regions. Keywords: Assisted reforestation, conservation, inert waste, rehabilitation, soil types.

• #tree root and stability studies
• #seedling growth and survival studies
• #agroforestry and silvopastoral systems
• #restoration ecology

Baccilus amyloliquefacins Strains Isolated in a Wastewater Treatment Plant: Molecular Identification and Amylase/Protease Production Capacity

Jean Jules Nana Ndangang, Alain-Martial Sontsa-Donhoung, Elvire Hortense Biyé, Dumitra Răducanu, Narcis Bârsan, Anne Ayo et 8 autre(s)

Environments

This study centred on isolating and characterizing Bacillus amyloliquefaciens strains derived from wastewater sludge to assess their potential for sludge treatment. Samples were collected from the Etoa wastewater sludge treatment plant in Yaounde, Cameroon. The isolates were obtained on nutrient agar medium and were identified through morphological and biochemical characterization, followed by 16S rRNA gene sequencing analysis. The sequences showed 99–100% similarity with Bacillus amyloliquefaciens strains in the NCBI database. The isolates exhibited significant in vitro enzymatic activities, including catalase, amylase, and protease production, indicating their ability to degrade hydrogen peroxide starch and proteins, respectively. The results confirmed the in vitro potential of Bacillus amyloliquefaciens as a promising microbial agent for organic matter degradation in wastewater sludge. Although the findings were limited to laboratory conditions, they provided a foundation for future pilot-scale or in situ studies aimed at validating their practical efficiency. This research contributes to the development of microbial-based and eco-efficient strategies for sustainable sludge management.

• #enzyme production and characterization
• #wastewater treatment and nitrogen removal
• #biopolymer synthesis and applications
• #bacillus amyloliquefaciens

Contribution of corporate capital structure on compliance to forestry law in Cameroon

Charles Ndifon Nchacham, Elvire Hortense Biyé, Charly Tchapda, Kenneth Bah

International Journal of Biological and Chemical Sciences

The need to understand the persistence of unsustainable forest logging within existing titles can provide ample knowledge on this practice, hence setting a reference base required to design appropriate strategy to counter illegal logging practices. The main objective of this research was to model algorithms to determine the overall effect of corporate capital structure on the compliance to forestry law by quoted logging companies in Cameroon. Primary and secondary data used for the research was collected directly from 40 logging companies found in the Lom and Djerem, Ocean and Upper Sanaga Divisions. Data collected from secured documents on species logged and volume, corporate data on debt rates, equity, company age and size were all obtained during interviews with responsible personnel. Information on logging offenses and their frequency of occurrence was btained from both the centralized and decentralized services of the Ministry of Forestry and Wildlife. Other existing research documents from other stakeholders were exploited. Collected data was entered into an Excel spreadsheet and analyzed using R. Capital structure is observed to significantly influence sustainable forest management performance in the Cameroonian forest logging industry at a 0.01 level of significance.

• #private equity and venture capital
• #corporate finance and governance
• #mining and resource management
• #logging

Traditional knowledge of plants used in hunting and fishing practices among Baka hunter-gatherers of eastern Cameroon

Evariste Fongnzossie Fedoung, Marlène Tounkam Ngansop, Takanori Oishi, Achille Bernard Biwôlé, Elvire Hortense Biyé, Mitsuo Ichikawa

Journal of Ethnobiology and Ethnomedicine

BACKGROUND: Baka hunter-gatherers have a well-developed traditional knowledge of using plants for a variety of purposes including hunting and fishing. However, comprehensive documentation on the use of plants for hunting and fishing in eastern Cameroon is still lacking. METHOD: This study aimed at recording plants used for hunting and fishing practices, using focus group discussion, interviews and field surveys with 165 Baka members (90 men and 75 women) of different age groups in 6 villages. RESULTS: The most frequent techniques used for hunting and fishing are the use of animal traps, fishing lines, dam fishing, hunting with dogs and spear hunting. We recorded a total of 176 plant species used in various hunting practices, the most frequently cited one being Zanthoxylum gilletii (De Wild.) P.G.Waterman, Greenwayodendron suaveolens (Engl. & Diels) Verdc., Microcos coriacea (Mast.) Burret, Calamus deërratus G.Mann & H.Wendl. and Drypetes sp. These plants are used for a variety of purposes, most frequently as hunting luck, psychoactive for improving the dog's scent and capacity for hunting, materials for traps, and remedies for attracting animals and for making the hunter courageous. CONCLUSION: Plants used for hunting purposes here are embedded in a complex ecological and cultural context based on morphological characteristics, plant properties and local beliefs. This study provides a preliminary report and leaves room for further investigations to improve the documentation of the traditional knowledge systems of the studied community.

• #ethnobotanical and medicinal plants studies
• #primate behavior and ecology
• #african botany and ecology studies
• #fishing

Caractérisation de l’infestation de Tapinanthus dodonaeifolius (Loranthaceae) chez le karité (Vitellaria paradoxa) au Tchad

Idriss Tourgou Kanika, Christophe Djekota Ngarmari, Elvire Hortense Biyé

Flora et Vegetatio Sudano-Sambesica

Au Tchad, à cause de ses retombées financières une attention particulière est prêtée aux arbres à karité (Vitellaria paradoxa C.F.Gaertn.). Cependant, cette culture est menacée par les plantes vasculaires parasites de la famille des Loranthaceae. La présente étude a été effectuée dans 3 sites dans la région du Mandoul pour évaluer l’ampleur des attaques de Loranthaceae (gui africain) sur des arbres en fonction des classes de circonférence du tronc à 1,5 cm du sol. Elle a consisté à dénombrer sur une de surface, les arbres à karité infestés et les touffes de parasites rencontrées sur ces arbres, afin de déterminer leur taux et leur intensité d’infestation. Les résultats obtenus montrent que Tapinanthus dodonaeifolius (DC) Danser a été trouvée comme la seule espèce de Loranthaceae qui parasite les arbres karité étudiés dans la zone d’étude. Le taux moyen d’infestation estimé à 73% augmente avec l’âge des arbres karité. La moyenne d’intensité de l’infestation/arbre (2,75 touffes à Békôh, 2,27 à Yomi and 2,04 à Bébopen) montre que Tapinanthus dodonaeifolius constitue une réelle menace pour les peuplements de karité dans la zone d’étude. Il reste à rechercher le seuil d’infestation qui provoque une réduction significative de la fructification. Pour l’instant, bien que pénible à cause de la hauteur des arbres adultes, la lutte mécanique contre les Tapinanthus par la coupe systématique des branches infestées est urgente dans les parcs à karité dans cette zone d’étude.

• #african botany and ecology studies
• #plant parasitism and resistance
• #agriculture and rural development research
• #loranthaceae

Using transect sampling to determine the distribution of some key non-timber forest products across habitat types near Boumba-Bek National Park, South-east Cameroon

T. Marlène Ngansop, Elvire Hortense Biyé, F. Evariste Fongnzossie, Preasious F. Forbi, Cédric Djomo Chimi

BMC Ecology

BACKGROUND: Understanding the variation in distribution and abundance of non-timber forest products (NTFP) species is a crucial step in achieving their conservation and sustainable use. At the northern periphery of the Boumba-Bek National Park in Southeast Cameroon, little is known about which habitat type contain the highest abundance of NTFP species. In this study, we assessed habitat diversity and variation in the abundance of eight priority NTFP species comprising: Afrostyrax lepidophyllus, Baillonella toxisperma, Irvingia gabonensis, Panda oleosa, Pentaclethra macrophylla, Ricinodendron heudelotii, Scorodophloeus zenkeri and Tetrapleura tetraptera. The inventory was done along 16 linear transects of 5000 m × 20 m, and all the individuals, from juveniles (DBH < 5 cm) to mature trees (DBH > 5 cm) of the eight NTFPs were recorded. Habitat types were characterized along transects following basic forest classification system used in ecology and then measured. RESULTS: In total, 13 different habitat types were identified with young secondary forests and periodically flooded forests representing 32.70% and 26.31% respectively. The least represented habitat was young fallows with Chromolaena odorata (0.08%). Seven NTFPs (A. lepidophyllus, B. toxisperma, I. gabonensis, P. oleosa, P. macrophylla, R. heudelotii and T. tetraptera) were predominantly represented in young secondary forests whereas S. zenkeri was more abundant in young Marantaceae secondary forests. The different types of young secondary forests identified seem to be favourable for the growth of the eight NTFPs. CONCLUSIONS: This study demonstrated that habitat fragmentation driven by human activities such as industrial logging and shifting cultivation destroy the forest ecosystems and has a strong influence on the sustainability of the major NTFPs in the locality.

• #african botany and ecology studies
• #conservation, biodiversity, and resource management
• #cocoa and sweet potato agronomy
• #transect

Approche ethnobotanique et ethnopharmacologique des plantes utilisées dans le traitement traditionnel de l’ulcère de Buruli à Akonolinga (Cameroun)

Hervé Narcisse Bayaga, Nicole Marie Guedje, Elvire Hortense Biyé

International Journal of Biological and Chemical Sciences

Peu de données sont disponibles sur les plantes utilisées dans le traitement traditionnel de l’Ulcère de Buruli au Cameroun. Cette étude avait pour objectif l’identification des espèces et la caractérisation des recettes anti-ulcères de Buruli dans l’arrondissement d’Akonolinga. L’enquête ethnopharmacologique a permis d’identifier 25 plantes utilisées contre l’Ulcère de Buruli. L’écorce des tiges (41,1%), les tiges (26,8%) et les feuilles (25%) étaient les organes les plus utilisés. La décoction (64,3%) et le pilage (23,2%), étaient les modes de préparation prépondérants, s’administrant par voie externe, principalement par massage et désinfection de la lésion (64,3%) et en cataplasme (14,3%). L’analyse des citations d’usages, des similitudes d’emplois et convergence d’usage a montré que Musa parasidiaca, Mitracarpus villosus, Aframomum melegueta, Elaeis guineensis et Spathodea campanulata faisaient partie des espèces aux convergences d’usages remarquables entre différentes régions géographiques, tandis que sept autres, Petersianthus macrocarpus, Momordica cabraei, Cassia spectabilis, Citrus medica, Terminalia superba, Ceiba pentandra et Ipomoea aquatica, constituaient l’autre groupe d’espèces les plus significatives. En mettant en évidence ces douze espèces d’intérêt, cette étude a une applicabilité en innovation thérapeutique, par le raisonnement ethnopharmacologique, en concourant à la sélection des espèces et à l’orientation des évaluations chimiques, pharmacologiques ou cliniques prioritaires conduisant au développement de phytomédicaments dont l’Afrique a besoin pour ses pathologies endémiques.Mots clés : Ulcère de Buruli, recettes traditionnelles, espèces végétales d’intérêt, raisonnement ethnopharmacologiqueEnglish Title: Ethnopharmacological and ethnobotanical approach of medicinal plants used in the traditional treatment of Buruli ulcer in Akonolinga (Cameroon)English AbstractFew data are available concerning plants used in the traditional treatment of Buruli ulcer in Cameroon. This study aimed to identify species and characterize anti-Buruli ulcer recipes in the Akonolinga district. The ethnopharmacological survey has enabled to identify 25 plant species used against Buruli ulcer. The plant parts mostly used were stem bark (41.1%), stem (26.8%) and leaves (25%). Decoction (64.3%) and pounding (23.2%), the most dominant preparing method, were administrated externally, mostly by massage and disinfection (64.3%) and by local poultice application (14.3%). The analysis of relative frequency of citation, as well as the search of similarity and convergence of use, have shown that Musa parasidiaca, Mitracarpus villosus, Aframomum melegueta, Elaeis guineensis and Spathodea campanulata were among species exhibiting remarkable convergence of use between different geographical regions; while seven others, Petersianthus macrocarpus, Momordica cabraei, Cassia spectabilis, Citrus medica, Terminalia superba, Ceiba pentandra and Ipomoea aquatica, formed another most significant species group. In highlighting those 12 species of interest, this study has direct bearing in drug design and innovation by the ethnopharmacological reasoning, thereby contributing to species selection and direction for prior chemical, pharmacological and clinical assessments leading to plant-based drug development that Africa needed for its pandemic pathologies.© 2017 International Formulae Group. All rights reserved.Keywords: Buruli ulcer, traditional recipes, plant species of interest, ethnopharmacological reasoning

• #mycobacterium research and diagnosis
• #phytochemistry and bioactive compounds
• #infectious diseases and mycology
• #biology

Diversity of Edible and Medicinal Mushrooms Used in the Noun Division of the West Region of Cameroon

André Ledoux Njouonkou, Eske De Crop, Abdoulayi Mbouombouo Mbenmoun, Tonjock Rosemary Kinge, Elvire Hortense Biyé, Annemieke Verbeken

International journal of medicinal mushrooms

This article presents discussions of mushrooms as a source of food, income, as well as medicine among the Bamoun people of the highlands of West Cameroon, where the vegetation is mainly savannah mixed with forest galleries. Like most tribes in tropical Africa, the Bamoun people use a wide range of natural products as mushrooms. This study attempts to identify the various mushrooms exploited by the Bamoun. Ethnomycological surveys and field trips were conducted over 4 years in several villages in the Noun Division. Samples of wild mushrooms were collected from both the savannah and the forest galleries. These were described, preserved, and identified. The study shows that the Bamoun people use at least 40 species of mushrooms for either food or medicine. These species belong to 8 genera: Auricularia, Cantharellus, Ganoderma, Pleurotus, Lactarius, Lactifluus, Russula, and Termitomyces. Species of genera Lactarius, Lactifluus, Russula, and Termitomyces are most often used for food, whereas Ganoderma spp. and Pleurotus tuber-regium are mainly exploited for medicinal purposes. This survey provides an overview of the diversity of mushrooms and their importance to the local people of this area. Since some of the species mentioned by the local population were not fruiting at the time of our field trips, additional investigations are needed to further clarify the diversity and the usage of mushrooms in this region.

• #fungal biology and applications
• #phytochemistry and bioactivity studies
• #mycorrhizal fungi and plant interactions
• #russula

Allocation de carbone des peuplements de Cyperus papyrus L. (Cyperaceae) dans les zones humides forestières : cas de la zone urbaine et péri-urbaine de Yaoundé (Cameroun)

Léon Dieudonné Kono, Marie-Alain Mbarga Bindzi, Hyacinthe Angoni, Elvire Hortense Biyé, David Guy Hervé Endanga

Revue d Écologie (La Terre et La Vie)

Carbon allocation of stands of Cyperus papyrus L. (Cyperaceae) in forested wetlands : the case of urban and peri-urban areas in Yaoundé (Cameroon). Carbon allocation of various populations of C. papyrus was investigated in and around Yaoundé urban area, in order to recommend the sustainable management strategies for this species. The transect method was adopted for data collection in seven selected sites from two types of microhabitats : borders (BOR) and permanently wet (ZPH) areas where C. papyrus is found. The data collection focused on above-and below-ground biomass, litter and soil obtained from 0-30 and 30-60 cm depth. The dry matter (MS) obtained after drying the biomass and litter in an oven was converted to carbon. Most of the carbon was stored in the soil and underground compartment of the Retention Pond 1 and 2 in the urban area. In other sites, the soil is the only main compartment to sequester carbon ; with more than 96 % in both BOR and ZPH. The highest stock of carbon is obtained in the urban area (114.80 T. ha-1 to 341.50 T. ha-1) but reduces at its periphery (109.15 T. ha-1 to 227.90 T. ha-1) when C. papyrus populations is destroyed by man for agricultural activities. The main factors influencing carbon stocks in sequestering compartments include the density and stems diameter on one hand, then the weight of carbon content and pH on the other hand.

• #african botany and ecology studies
• #botany and plant ecology studies
• #agriculture and rural development research
• #forestry

Sustaining Gnetum L. (Gnetaceae) in Africa through improved taxonomy and domestication

Elvire Hortense Biyé

Gnetum L. (Gnetales) plants are useful gymnosperms in Africa that alleviate poverty in the local community as they are widely sold and used as vegetable (‘eru’). The African species of this genus are however difficult to distinguish from one another, are threatened due to over-exploitation and therefore face the risk of disappearing before they are adequately known. This study aims to clarify the taxonomy of the vulnerable Gnetum species in Africa and to promote sustainable utilization and conservation of the species. Thus, sustainable strategies involve, on the one hand, the identification of various species suitable for conservation and, on the other hand, the supply of management guidelines for cultivation based on taste data. The specific objectives undertaken in the genus Gnetum in Africa are to:&#13;\n- investigate the various species to be recognized in the genus in Africa and the important features that distinguish them.&#13;\n- determine how the cultivated material relates to the naturally occurring&#13;\ntaxa.&#13;\n- elucidate species limits based on genetic patterns.&#13;\n- identify anatomical features useful to distinguish species in general and&#13;\nto match female plants to corresponding males in particular.&#13;\n- evaluate any variation in taste between Gnetum populations.&#13;\n- examine the mechanism involved in seed germination in order to&#13;\npromote their sustainable utilization in cultivation.&#13;\n&#13;\nTo address the taxonomic problems in the genus Gnetum in Africa, the types and the original descriptions were used to identify and help attribute names to the various forms; numerical analyses of morphological characters were carried out to illustrate the distribution of any variation among various specimens; molecular and anatomical tools were also used to reveal additional characters to differentiate and recognize species and to match male and female specimens. In an attempt to sustain Gnetum plants in Africa so that the lives of those who depend on it are not affected in the near future, several strategies are undertaken. Taste analysis was applied to explore species with the best taste for promotion and the type of leaves to harvest thus limiting mass destruction of the entire Gnetum plant. So variation in taste of the leaves of Gnetum (‘eru’ meal) with respect to species, provenance and age of leaf was investigated using both questionnaire survey and the gustatory approach. Seed germination trials were carried out as a possible means to selective cultivation that could result in the bulk production of Gnetum plants and so relieve pressure on natural populations.&#13;\n&#13;\nGnetum species in Africa present different morphological structures useful for taxonomic clarification. These species are better distinguished morphologically by their reproductive structures; the vegetative features vary within species and even on the same specimen. The original applications of the names Gnetum africanum Welw. and Gnetum buchholzianum Engl. have been clarified and two new African species have been identified: Gnetum interruptum E.H. Biye sp. nov. and Gnetum latispicum E.H. Biye sp. nov. A key to these species is provided and useful characters to recognize species in the genus Gnetum in Africa are discussed.&#13;\n&#13;\nTaste analysis permitted the identification of specific factors for horticulturalists to know which species to propagate for leaves of Gnetum. For example in the course of the investigation, it was found that the leaves of G. buchholzianum taste best in ‘eru’ meals, that good Gnetum leaves for ‘eru’ were collected from every region but only the young leaves were best for ‘eru’ meals. In addition, seeds of Gnetum species in Africa are orthodox i.e. they exhibit dormancy but nevertheless they germinate under artificial or nursery conditions when exposed to the appropriate treatments. The study clarified the taxonomic status of Gnetum species in Africa and also provided information to identify the forms with good agronomic traits and the conservation strategy to explore in order to sustain Gnetum in Africa for future uses.

• #plant diversity and evolution
• #african botany and ecology studies
• #plant and fungal species descriptions
• #taxonomy (biology)

A clarification of Gnetum L. (Gnetaceae) in Africa and the description of two new species

Elvire Hortense Biyé, K. Balkwill, G.V. Cron

Plant Systematics and Evolution

• #plant diversity and evolution
• #plant and fungal species descriptions
• #african botany and ecology studies
• #herbarium

Phénologie florale dans une jeune forêt secondaire hygrophile du Cameroun

Marie-Alain Mbarga Bindzi, Alain Lacoste, Amougou Akoa, Elvire Hortense Biyé

Acta Botanica Gallica

This work was carried out to study the flowering phenology in a young forest of about fifteen years old. For its location in the intrication zone of mixed forests, this forest was made up of both evergreen and deciduous species. Six strata and distinct sub-strata, with already defined biophysiognomic types and according to the stratification-type model, were observed to study flowering phenology through its rhythm, diversity and intensity. Generally, the floral diversity and intensity showed a parallel evolution, except during the long dry season and part of the short rainy season, in the course of which mass flowering were observed. At the level of some strata, seasonal expression greatly differed with that of the whole forest. The model of a unique annual flowering during the long rainy season or the long dry season, combined with an average anthesis duration, was observed in a good number of species in this forest. Nevertheless, when considering flowering duration, some variations in phenologic behaviour with respect to stratum were noted within certain species.

• #african botany and ecology studies
• #plant and animal studies
• #plant biochemistry and biosynthesis
• #evergreen