Aspectos ecológicos de um trecho de floresta de brejo em Itatinga, SP: florística, fitossociologia e seletividade de espécies

Abstract

(recebido em 11/10/95; aceito em 26/12/96) ABSTRACT -(Ecological aspects of a swamp forest at Itatinga, SP: floristics, phytosociology and species selectivity). On present work, it was studied a swamp forest with 2 ha area, at the EUCATEX Ltda.'s Santa Irene farm, at Itatinga (48 o 38'53.2 " W and 23 o 17'41.6 " S), São Paulo state. Phytosociological survey was executed through census method in 1 ha of forest remaining, where all individuals with PBH (perimeter at breast height) > 15 cm were recorded. 1310 individuals were sampled, belonging to 28 families, 34 genera and 39 species of shruby-tree layer. The most important families in IVC were Clusiaceae (53.49), Burseraceae (41.30), Euphorbiaceae (31.42), Podocarpaceae (9.04), Caesalpiniaceae (6.99), Myrsinaceae (6.38), Melastomataceae (5.75), Anacardiaceae (5.70), Arecaceae (4.51) and Styracaceae (4.44). These 10 families accounted for 74.50% of total IVC. The most important species in IVC were Calophyllum brasiliense (53.49), Protium almecega (41.30), Pera obovata (14.46), Podocarpus sellowii (9.04), Hyeronima alchorneoides (8.68), Copaifera langsdorffii (6.99), Rapanea guianensis (5.72), Tapirira guianensis (5.70), Miconia ligustroides (5.62) e Sebastiania serrata (4.71), wich accounted for 77.84% of total IVC. The Shannon's diversity index (H') was 2.751 nats/individuals. Based on floristic and phytosociological criterious, the species sampled was divided in two groups: a) peculiar species, with the subgroups of exclusive and no exclusive e b) complemental, with the subgroups of dry areas and indifferents.