SPATIAL-DISTRIBUTION OF SEEDLINGS AND YOU NG PLANTS OF IRYANTHERA-HOSTMANNII (BENTH.) WARB. IN FRENCH-GUYANA TROPICAL RAIN-FOREST

The regeneration of a tropical rain-forest tree Iryanthera hostmannii was studied by analysing the occurrence of established seedlings and t heir densities. The study was performed in French Guyana, in an evergr een forest under a wet tropical climate. I. hostmannii is an endozooch orous species presenting the 'bird-monkey' syndrome. Every year from 1 986 to 1994, we measured and mapped recruitment, survival, the height of each individual and mortality on a 50 x 50-m plot. Twelve adult ind ividuals (six males and six females) were present on the plot. The dis tribution of the seedlings showed patches of high density unrelated to the locations of fruiting individuals. The effect of perches, however , was very marked. Dissemination in I. hostmannii is dose to the model 'small number of high quality dispersers for a high-investment plant species'. It is a species that tolerates shade at all stages of develo pment bur growth of the young plants is enhanced by patches of light. ((C) Academie des sciences/Elsevier, Paris.)