Endogenous knowledge and uniqueness of traditional communities in Northern Léfini Reserve (Republic of Congo)

Background: This study was carried out in three traditional communities in the northern sector of the Léfini reserve (Banga, Edzouala and Mpoh). The aim of this research is to capitalise on the secular achievements of the socio-cultural foundations of traditional communities, with a view to preserving the societal values associated with herbal medicine. The study was prompted by the observation that traditional knowledge of medicinal plants is dying out in Africa, particularly in the Congo. Methods: In addition to bibliographic compilation, the methodological approach is based on a floristic inventory using walk-in-the-woods and show-and-tell methods, as well as an ethnobotanical survey. Informants were at least 15 years old and divided according to gender and socio-professional group. The sample was selected using a stratified probabilistic method. Prior to the fieldwork, a literature review provided information on the phytogeographical distribution and known uses of the species in their area of distribution. Depending on the circumstances, the ethnobotanical survey consisted of individual or group interviews. Results: The floristic inventory revealed 64 species from 35 families. The Asteraceae and Fabaceae are the most represented in the medicinal flora. The most widely used species, to varying degrees, are Nauclea latifolia Sm., Dysphania ambrosioides (L.) Mosyakin & Clemants, Chromolaena odorata (L.) R.M.King & H.Rob., Costus afer Ker Gawl., Garcinia kola Heckel, Psidium guajava L., Uraria picta (Jacq.) Desv. ex DC., Gymnanthemum amygdalinum (Delile) Sch.Bip., Senna occidentalis (L.) Link and Cissus aralioides (Baker) Planch.. Of the taxa surveyed, 39.06% are at risk due to non-ecological logging (felling, uprooting and debarking). The high values of the ethnobotanical indices (ethnobotanical use value (UV), informant consensus factor (ICF) and fidelity level (FL)) show a strong involvement of the taxa and parts used in recipe preparation, within these traditional societies. The study highlights fourteen therapeutic indications that vary according to locality and socio-professional category. Infectious and parasitic diseases, as well as ill-defined symptoms, signs and morbid states, are the most frequent ailments in the communities. The groups with the most diversified knowledge are women, individuals aged 15 to 25 years and over 45 years, and the Tékés. Conclusions: The use of flora for medicinal purposes is unique among the communities surveyed. Despite modernization, endogenous values have been preserved, and empirical knowledge has been passed down from generation to generation. However, given the vulnerability of prized taxa and ecosystems, endogenous knowledge is under serious threat. The domestication of certain taxa can be seen as a way of perpetuating them and preserving endogenous knowledge. However, this domestication mainly concerns non-native taxa. Keywords: Ethnobotany, endogenous knowledge, medicinal plants, Léfini reserve, traditional communities, Traditional use.