Abstract

Several forms of degradation reduce the size and the ecological value of forest ecosystems such as the introduction of alien species. In other to study the level of the exotic plant species Azadirachta indica invasion in forest fragments of Southern Togo, data collection was carried out in thirteen forests where 65 rectangular plots of 500 m² were set up to record the plant species diversity and other 52 plots of 625 m² to count the tree and to measure their height and diameter. The data analysis was carried out by determining the relative density, the relative dominance and the relative frequency of the plants species. The results show that 414 plant species including 19 identified as alien have been identified in the forest fragments. They are divided into 15 families with an invasion rate of 4.58% and a frequency of 53.85% for A. indica. These data reveal the importance of the invasion phenomenon of the local forest flora, especially inside the juvenile population.

Key words: Forest fragments, Southern Togo, alien species, invasion, Azadirachta indica.