Résumé
Agricultural practices in cocoa cropping systems have been studied worldwide with a strong focus on production. Most of the attempts to improve cocoa production have been made through technical practice improvement only focused on the cocoa tree itself or the cocoa tree population within the plot. However, few approaches actually consider the cocoa field as it is most often cultivated worldwide, i.e. a complex association of species that include cocoa trees at different ages, but also fruit and timber trees as well as different species of lianas, mosses, orchids, bromeliads and shrubs. Moreover, most studies barely consider the existing interactions between one given cocoa cropping system and the other neighbouring systems, whether they are cocoa or non cocoa based, cultivated or non cultivated. As a result, the role of biodiversity in cocoa orchards and the role of cocoa orchards in environmental services such as biodiversity conservation are often unknown or not considered. We propose here a methodology for the study of biodiversity in cocoa production landscapes that takes into account three integration levels : (i) the plot (ii) the agroecological patterns, and (iii) the landscape. At the plot level, we studied i) physical characteristics of the vegetation structure including plant population density, strata location and light penetration, ii) local knowledge regarding uses of plants and animals, and iii) agricultural practices. Agroecological patterns are geographical structures composed of spatial patches characterized by specific ecological and social factors. We offer to build a typology of cocoa fields spatially localised taking into account their immediate neighbouring cropping systems. The patterns include a description of i) the nature of the systems (with or without cocoa) which have a common border with the cocoa field, and ii) the nature and intensity of biological interactions between the systems in the pattern. Finally, the territory level allows to integrate the functional and structural effects of the agroecological patterns and their interactions in the landscape. We suggest the need for an analysis of the interactions between these three integration levels to assess the environmental services provided by cocoa and other agroforestry systems in tropical landscapes. (Résumé d'auteur)