SUCCESSIONAL DYNAMICS OF TREE SPECIES DURING FOREST RECOVERY IN THE SOUTHEAST OF COTE D’IVOIRE

Résumé

Secondary forests constitute currently a large and growing component of forest cover, and can be found to be very important for a wide range of goods and services. A synchronic study has been achieved about successional stages in the forest recovery in the Southeast of Côte d’Ivoire. The objectives were to determinate trees species diversity at different sucessional stages and the auto-ecological characters of the most abundant species following abandonment of agricultural areas. Tree species with dbh ≥ 2.5 cm were counted in 85 plots from fallows gradient and 20 plots from two old-growth forests as control. Five successionnal stages were identified based on patch occupancy of the 10 best competitor / colonizer advantages. Tree species richness and diversity were significantly higher in the oldest forests. During the first 30 years of secondary regrowth, richness and diversity profile have not been influenced by age since abandonment. At least 14 % of forest tree sepcies were surveyed in young fallows. From two to five pioneer, non pioneer light demanding and shade-tolerant species have the most abundant accoding to successionnal stages. Sixty percent of these species were confined to the Guineo-Congolian region and at least 80 % of diaspores were sarcochory and sclerochory types. This study shown that farmers practices in the rural area, were favorable to forest recovery in terms of faster regeneration after agricultural abandonment. This rapid forest recovery can provide the availability of farmlands and can be a good opportunity for human pressures reduction on protected forests.