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bioRxiv · 10.1101/680660

What Determine the Distribution and Richness of Wild Spices in the Sudano-Guinean zone of Benin, West Africa?

Abstract

In Benin, most of the spices used for food, medicine and ceremony are gathered from the wild as little attempt has been made so far for their domestication and cultivation. Consequently, many wild spices are prone to overexploitation and threatened by habitat loss. Also, little information is available regarding their occurrence areas and the factor determining their geographical distribution and richness. This study aimed at i) mapping the distribution and the richness of 14 wild spices, and ii) assessing the drivers of their distribution and richness patterns in the Sudano-Guinean zone of Benin. Data were collected during field exploration and from the database of the Global Biodiversity Information Facility. Species distribution was mapped, and a grid of 10 x 10 km cells and a circular neighborhood option with a radius of 10 km was used to assign points to grid cells, then species richness was mapped. The species were unequally distributed across the study area. High species richness occurs in Bassila and Zou phytodistricts. Three spice-rich areas are needed to capture all the wild spices at once. Interaction of mean temperature of driest quarter, altitude, and precipitation seasonality significantly shaped the distributional range of three wild spices (Aframomum alboviolaceum, Uvaria chamae and Zanthoxylum zanthoxyloides), while the same factors in addition to clay content between 5-15 cm, contributed significantly to create appropriate conditions for the cooccurrence of several species.\n\nResumeAu Benin, la plupart des epices utilisees pour lalimentation, en medecine et pour les ceremonies sont collectees dans la nature car tres peu de tentatives ont ete faites pour leur domestication et leur culture. Par consequent, de nombreuses especes depices sauvages sont surexploitees et se retrouvent menacees par la destruction de leur habitat. Aussi, peu dinformations sont disponibles sur leurs zones doccurrence et les facteurs influencant leur distribution geographique et leur richesse. Cette etude visait a i) cartographier la distribution et la richesse de 14 epices sauvages, et a ii) evaluer les facteurs influencant leurs distribution et richesse dans la zone Soudano-Guineenne du Benin. Les donnees ont ete collectees au cours dexplorations sur le terrain et a partir de la base de donnees du Global Biodiversity Information Facility. La distribution des especes a ete cartographiee et une grille de 10x10 km a servi de base pour la cartographie de la richesse en especes. Les especes etaient inegalement distribuees dans la zone detude. Des zones de grande richesse en epices sont presentes dans les phytodistricts de Bassila et du Zou. Trois zones de forte diversite en epices sont necessaires pour capturer toute la diversite du groupe fonctionnel des epices sauvages. Linteraction de la temperature moyenne du trimestre le plus seche, laltitude, et la saisonnalite des precipitations ont significativement influence la distribution de trois epices sauvages (Aframomum alboviolaceum, Uvaria chamae et Zanthoxylum zanthoxyloides). Ces trois facteurs, ajoutes au taux dargile dans le sol, ont contribue a la creation des conditions favorables pour la cooccurrence de plusieurs especes depices sauvages.\n\nMots clesarbre dinference conditionnelle, epices sauvages, especes negligees et sousutilisee, SIG, systemes dinformation geographiques,

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BibTeXRIS

Kafoutchoni, K. M., Idohou, R., Salako, K. V., Agbangla, C., Assogbadjo, A. E.. 2019-06-28. What Determine the Distribution and Richness of Wild Spices in the Sudano-Guinean zone of Benin, West Africa?. https://doi.org/10.1101/680660

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