Abstract
Remnants of the highly fragmented Atlantic Coastal Forest on the alluvial plains of Rio de Janeiro State, Brazil, have been little studied. Sample plots, totaling one hectare, were inventoried using a DBH ≥ 5 cm exclusion criterion. Allometric relationships were used to define the canopy as having a DBH ≥ 10 cm and height ≥ 10 m. A total of 486 individuals were sampled, comprising 97 species belonging to 31 families. The Shannon diversity index (H´) was 3.98 nats/ind, and the equitability (J) was 0.87. These were considered significant values for an area of Atlantic Coastal Forest in that state. Among the families with the highest species richness (73% of the total number of species) were: Fabaceae, Euphorbiaceae, Lauraceae, Moraceae, Myrtaceae, Annonaceae, Bignoniaceae, Melastomataceae, Clusiaceae, Meliaceae, and Sapotaceae. Among the species with the highest VIs were: Eriotheca pentaphylla, Symphonia globulifera, Tabebuia umbellata, Xylopia brasiliensis, Calophyllum brasiliense, Euterpe edulis, Tabebuia cassinoides, Platymiscium floribundum, and Guarea kunthiana. The indicator species for alluvial lowland ombrophilous forests were: Eriotheca pentaphylla, Calophyllum brasiliense, and Eugenia expansa. The results of this survey pointed out high richness and diversity to the Atlantic Ombrophilous Dense Forest submontane alluvial, in spite the high human interference in the landscape, during a long scale the time, where, on the other hand, it's expected a greater number of species, in different kinds of habitats resulted, will provide a heterogeneity spatial distribution in area of ecological temporal transition.
Key words:
Atlantic Coastal Forest; floristics; community structure; canopy; lowland forest; alluvial forest