ABSTRACT
Marantaceae forests are tropical rainforests characterized by a continuous understory layer of perennial giant herbs and a near absence of tree regeneration. Although widespread in West-Central Africa, Marantaceae forests have rarely been considered in the international literature. Yet, they pose key challenges and opportunities for theoretical ecology that transcend the borders of the continent. Specifically, we ask in this review whether open Marantaceae forests and dense closed-canopy forests can be considered as one of the few documented examples of alternative stable states in tropical forests. First, we introduce the different ecological factors that have been posited to drive Marantaceae forests (climate, soil, historical and recent anthropogenic pressures, herbivores) and develop the different hypotheses that have been suggested to explain how Marantaceae forests establish in relation with other vegetation types (understory invasion, early succession after disturbance, and intermediate successional stage). Then, we review the underlying ecological mechanisms that can explain the stability of Marantaceae forests in the long term (tree recruitment inhibition, promotion of and resilience to fire, adaptive reproduction, maintenance by megaherbivores). Although some uncertainties remain and call for further empirical and theoretical research, we found converging evidence that Marantaceae forests are associated with an ecological succession that has been deflected or arrested. If verified, Marantaceae forests may provide a useful model to understand critical transitions in forest ecosystems, which is of particular relevance to achieve sustainable forest management and mitigate global climate change.
Subject(s)
Forests , Rainforest , Trees/physiology , AfricaABSTRACT
The ethnobotanical and phytotherapeutic study conducted in Mvouandzi (4°10'00â³ S, 13°25'00â³ E), sub-prefecture of Kayes (Bouenza - Congo), is based on the floristic inventory, the personalized interviews and focus groups. The target population, aged between 15 to 70 years or more, is divided into 3 age groups, and consists of 46 informants (12 men and 34 women) who possess the plant secrets. The floristic inventory lists 60 useful species, corresponding to 53 genera and 35 families. The medicinal cohort is associated with 109 recipes and 57 diseases and symptoms. Classified as a sphere of diseases and symptoms, infectious and parasitic diseases predominate (27.11%) and retain 30.27% of recipes. All organs (vegetative and generative) intervene in the daily satisfaction of the needs of the populations. Ethno-sociological analysis reveals that the level of endogenous knowledge is proportional to the subjects' age and in this matter, women by virtue of their role as manager and guardian of morals, excel in the exploitation of empirical knowledge. Data on the value of ethnobotanical use, the informant consensus factor and the level of fidelity show that these plants are strongly involved in the primary care of this society. Notwithstanding the inseparable link between man and his environment, the value associated with this biodiversity, the socio-cultural foundation of the Kouni ethnic-linguistic community, is inevitably eroded. The reasons for this are the rural exodus, the main corollary of which is the ageing of the population, and the effects inherent in the construction of physical communication infrastructures.
