Ethnobotanical indicator values of Non-Timber Forest Products from the Djoumouna peri-urban forest in Brazzaville, Republic of Congo

Abstract

A study of the relationship between man and his environment was carried out in Brazzaville, Republic of Congo in the peri-urban forest of Djoumouna. Socio-economic and ethnobotanical surveys conducted among the human populations in riparian areas were supported by direct field observations and a review of the literature. Data were collected from a 2 km zone of influence around the Djoumouna forest. The group of survey participants, organized into four age groups, included all socio-professional categories and was made up of 143 heads of household. The survey participants were of both genders and ranged in age from 15 to over 45 years old. Ethnobotanical indicators were used as data analysis tools, specifically, ethnobotanical use-value, survey participant consensus factor, and level of fidelity. This study identified 13 plant species and more than 14 animal taxa as Non-Timber Forest Products (NTFPs) of animal and plant origin. Most of the taxa listed are used in traditional foods and/or phytotherapy. The low values of some ethnobotanical indicators show that these NTFPs, which are not highly sought after and valued by the population, are also rare in this peri-urban ecosystem. This observation is also valid when considering the involvement of survey participants by age group. However, the survey participant consensus factor reflects a unanimity of traditional exploitation of these NTFPs within the society. The analysis of the ethnobotanical data clearly show a difference in the level of exploitation of NTFPs between genders with men having more interest in finding and using NTFPs. Finally, the study indicates (i) gender specialization is associated with NTFP activities and exploitation, and (ii) a progressive erosion of traditional knowledge is occurring between age groups.

Trees Supplies and the Relevance of Ecosystem Services in Brazzaville Urban Environment

“…This accomplishment involves, in unequal proportions, all ecosystem services. The contributions associated with direct necessities (food, phytotherapeutic and wood-energy) are less favored by the group of informants than indirect related to regulatory services and socio-cultural services (income generation) [50,59,61]. The source of this observation would be the trivialization of direct aspects by the populations.…”

“…The index that shows the local importance of each species is the ratio of the frequency of citation (FC) by the total number of respondents (N) [47]. RFC = 𝐹𝐶 / 𝑁 (equation 7) (iii) Use value The use value of ecosystem services [48][49][50] is given by the formula Where Np = number of people who cited a type of ecosystem service or use; and N = total number of people who benefit from any ecosystem service.…”

“…The floristic composition of the urban woodland formation is characterized by a strong heterogeneity. Arboriculture, the basis of urban forestry, is a system marked by a high degree of specific richness associated with a floristic poverty [8,9,42,43,50,[53][54][55]. These characteristics are the markers of the corollaries of urbanization, which is carried out to the detriment of the spontaneous flora.…”

“…In the case of this study, the introduced taxa meet precise criteria based mainly on the daily satisfaction of the needs of the populations [58,59]. In relation to the impoverishment that the majority of citizen's experience, this daily satisfaction is, most often summarized in the provision of food, medicinal products, and wood-energy and finally constitute a source of income [50,55,59,60]. This dependence of populations on non-timber forest products (NTFPs) alone would explain the low species richness noted in urban forestry south of the Sahara and the pronounced dominance of taxa providing the most prized organs such as the fruits of Carica papaya, Dacryodes edulis, Persea americana, Mangifera indica.…”

“…The Informant Consensus Factor (ICF) emphasizes the synoptic view of the diversity of ecosystem services and the assessment of the relative importance of different categories of ecosystem services [50,59,67]. The high degree of value of this index for the three categories of ecosystem services marks a strong consensus of informants for each.…”