Caracterização florística, fitossociológica e regeneração natural do sub-bosque da reserva genética florestal Tamanduá, D.F.

Abstract

This work was carried out in the Tamanduá Forest Genetic Reserve, in Brasília, Brazil, comprised mainly by gallery forest. It aimed to assess the floristic composition, natural regeneration and the spatial distribution of the main woody species in the undergrowth. The species were Cariniana estrellensis (Raddi) O. Kuntze, Apuleia leiocarpa (Vogel) J. F.Macbr., Copaifera langsdorffii Desf., Anadenanthera macrocarpa (Benth.) Brenan, Virola sebifera Aubl., Hymenaea courbaril var. stilbocarpa (Hayne) Lee & Lang., Aspidosperma discolor A. St. Hil., Astronium fraxinifolium Schott and Schefflera morototoni B. Maguire, Stey. & Frodin, all considered priorities for in situ conservation. Five transects were used, each 10 meters wide, laid perpendicular to the main watercourse in the studied area. A total of 21,482 regenerants per hectare were found in 69 species, 53 genera and 39 families. The families which had the largest numbers of species as seedlings were, in descending order, Leguminosae (Fabaceae), Rubiaceae, Sapindaceae and Meliaceae. Surveying of young individuals, the dominant families with higher importance value (IV) were as follows: Meliaceae (32.78 %), Rubiaceae (13.92 %), Burseraceae (13.76 %), Rutaceae (8.54 %) and Hippocrateaceae (6.36 %), accounting for 75.36 % of total IV and 78.56 % of cover. All target species studied were represented among regenerants, especially Cariniana estrelllensis. However, only Copaifera langsdorffii and Virola sebifera were found among young individuals. A mixture quotient of 1:3 was calculated and indicates a forest rich in species, when compared to other similar forest formations. The spatial distribution of the regenerant species showed different patterns.