Infodoc : Sciences, Techniques et Culture

Secondary succession in a 19-v old tropical rainforest of French Guiana was investigated through the distribution pattern of primary forest species. The expérimental plot of 25 ha was logged to simulate conditions of a paper pulp cut. Enumeration of all plants of height 50 cm in 52 subplots 10 m x 10 m indicated the number of species and individuels in five species catégories; short-lived pioneer species, pioneer species that persist in mature forest, primary forest species capable of germinating in shade, primar-y forest species that indicate a preference for clearings (small gaps) in mature forest and understorey primary forest species. Change in proportion of the most abundant species (1 cm dbh) over the last 15 y indicated a decrease in short-lived pioncer species and an increa[...]

Secondary succession in a 19-v old tropical rainforest of French Guiana was investigated through the distribution pattern of primary forest species. The expérimental plot of 25 ha was logged to simulate conditions of a paper pulp cut. Enumeration of all plants of height 50 cm in 52 subplots 10 m x 10 m indicated the number of species and individuels in five species catégories; short-lived pioneer species, pioneer species that persist in mature forest, primary forest species capable of germinating in shade, primar-y forest species that indicate a preference for clearings (small gaps) in mature forest and understorey primary forest species. Change in proportion of the most abundant species (1 cm dbh) over the last 15 y indicated a decrease in short-lived pioncer species and an increase in pioneers that can persist in the mature forest. Proportion of species catégories per height class indicated that primary forest species were mainly round in the lower
height class in this forest which is largely dominated by secondary forest trec species forming a canopy that rarcly exceeds 20 m. Individuals of primary forest species were encountered on ARBOCEL as sprouts from large stumps, sprouts from juvéniles or as untraumatiscd saplings or juvéniles. The distribution pattern in a 4-ha area of 1 1 selected primary forest canopy tree species revealed an overall trend in recolonisation of this species category in the secondary forest.(...) (Résumé scannérisé)