Tree species identification on large-scale aerial photographs in a tropical rain forest, French Guiana—application for management and conservation

The French Guianan forest is an evergreen rain forest that contains approximately 100 deciduous tree species. The taxonomical distribution of the deciduous character is widely spread, and its presence or absence among some taxa, as well as its ancient origin, are arguments in favour of an endogenous origin. Leaf-fall periodicity was studied on a sample of 500 trees during a 2-year period. Periodicity is annual and seasonal. It is not correlated to rainfall and not linked to the occurrence of a dry season. It seems closely correlated to photoperiodical variations, even though those variations are weak (35 min at latitude 5°30′N). However, each tree has its own periodicity for leaves shedding. Therefore, there is a paradox between seasonality and individual periodicity of leaf fall. The existence of this paradox leads us to consider the hypothesis of an integration of endogenous and exogenous components in the determination of leaf-fall periodicity. Key words: deciduousness, French Guiana, phenology, photoperiodism, tree, tropical rain forest.

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Effect of endomycorrhizas and nematodes on the growth of seedlings of Dicorynia guianensis Amshoff, a tree species of the tropical rain forest in French Guiana

Annales des Sciences Forestières ◽

10.1051/forest:19970305 ◽

1997 ◽

Vol 54 (3) ◽

pp. 271-277 ◽

Cited By ~ 5

Author(s):

M Béreau ◽

E Louisanna ◽

J Garbaye

Keyword(s):

Tree Species ◽

Rain Forest ◽

Tropical Rain Forest ◽

French Guiana ◽

Dicorynia Guianensis ◽

Growth Of Seedlings

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Seed dispersal by red howling monkeys (Alouatta seniculus) in the tropical rain forest of French Guiana

International Journal of Primatology ◽

10.1007/bf02735451 ◽

1996 ◽

Vol 17 (2) ◽

pp. 239-258 ◽

Cited By ~ 81

Author(s):

C. Julliot

Keyword(s):

Seed Dispersal ◽

Rain Forest ◽

Tropical Rain Forest ◽

French Guiana ◽

Alouatta Seniculus ◽

Howling Monkeys

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Ecological processes maintaining differential tree species distributions in an Australian subtropical rain forest: implications for models of species coexistence

Journal of Tropical Ecology ◽

10.1017/s0266467400001474 ◽

2000 ◽

Vol 16 (3) ◽

pp. 387-415 ◽

Cited By ~ 20

Author(s):

Igor Debski ◽

David F. R. P. Burslem ◽

David Lamb

Keyword(s):

Species Composition ◽

Tree Species ◽

Rain Forest ◽

Large Scale ◽

Species Coexistence ◽

Common Species ◽

Size Class ◽

Differential Mortality ◽

Mixed Composition ◽

Large Scale Disturbance

All stems ≥ 1 cm dbh were measured, tagged, mapped and identified on a 1-ha plot of rain forest at Gambubal State Forest, south-east Queensland, Australia. The spatial patterns and size class distributions of 11 common tree species on the plot were assessed to search for mechanisms determining their distribution and abundance. The forest was species-poor in comparison to many lowland tropical forests and the common species are therefore present at relatively high densities. Despite this, only limited evidence was found for the operation of density-dependent processes at Gambubal. Daphnandra micrantha saplings were clumped towards randomly spaced adults, indicating a shift of distribution over time caused by differential mortality of saplings in these adult associated clumps. Ordination of the species composition in 25-m × 25-m subplots revealed vegetation gradients at that scale, which corresponded to slope across the plot. Adult basal area was dominated by a few large individuals of Sloanea woollsii but the comparative size class distributions and replacement probabilities of the 11 common species suggest that the forest will undergo a transition to a more mixed composition if current conditions persist. The current cohort of large S. woollsii individuals probably established after a large-scale disturbance event and the forest has not attained an equilibrium species composition.

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