STRUCTURE AND TREE DIVERSITY IN TRADITIONAL POPOLUCA COFFEE AGROECOSYSTEMS IN THE LOS TUXTLAS BIOSPHERE RESERVE, MEXICO

Résumé 0

"The structure and tree diversity of traditional coffee agroecosystems was studied in a Popoluca community within the Biological Reserve of Los Tuxtlas, Veracruz, Mexico, along an altitudinal gradient from 450 to 1000masl. The coffee agroecosystems were established in three physiognomic units: tropical semi-deciduous forest, tropical rain forest and deciduous forest. To understand the structure of the coffee agroecosystems, 30 plots of 400m2 were established. Sixty-four tree species and 23 herbs from 44 families were recorded. The most numerous families were Mimosaceae, Asteraceae, Fabaceae and Myrtaceae. The coffee agroecosystems had four layers: herbs, shrubs, lower trees, and upper trees. The shrub layer was dominated by four varieties of Coffea arabica. The species with the highest importance values were Apeiba tibourbou, Cordia alliadora and Inga vera. The species with the highest economic value were Acosmium panamense, Calophyllum brasiliense, Terminalia amazonia, and Vochysia guatemalensis. Coffee agroecosystems established in tropical semi-deciduous forest have higher diversity values, which has the lowest floristic similarity and the highest dissimilarity values. The complementarity index indicated a high rate of replacement and confirmed the fundamental role of peasant’s knowledge and management in the selection of species and the structure of the agroecosystem, but also in increasing and in some cases improving diversity without reaching the original diversity of the vegetation."