Effets de lisière sur la productivité du teck (Tectona grandis L.f.): étude de cas des teckeraies privées du Sud-Bénin

The present study aims to improve the production of teak wood (Tectona grandis L.f.) in private
plantations in southern Benin through the application of a central concept in landscape ecology: the edge effect. As teak is an heliophilous species, the hypothesis of a higher wood production in edges was tested on the basis of the basal area. Sixty-two private teak plantations were investigated and 10,667 trees were measured. The stratified sampling scheme in three distinct parts for each plantation (the centre, the edge and the summits) permitted to highlight the edge effect on wood production. For each part, a plot was installed and the diameter at breast height (dbh) was measured for all trees. The leaf area between the edge and the centre of plantations was measured. Finally, the influence of the spatial configuration of plantations and the direction of each side of these plantations on the production of wood was tested. Results show that the edge effect on the production of teak wood affects four planting lines, the first presenting a production of 150% relative to the centre. We noticed a significant influence of the edge on the leaf area of about 218% relative to the centre. No influence of the direction of the sides of the plantation was observed. The shape of the plantations presents a significant influence on the
wood production. These results permitted to propose a planting model included in an agroforestry system that optimizes the production of wood per area and having a succession of two planting lines interrupted by fields.