Florística de uma Floresta Estacional Semidecidual, localizada em ecótono savânico-florestal, no município de Bauru, SP, Brasil
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Data
2008-10-01
Autores
Ongaro Pinheiro, Marcelo Henrique
Monteiro, Reinaldo [UNESP]
Título da Revista
ISSN da Revista
Título de Volume
Editor
Soc Botanica Brasil
Resumo
Informações florísticas escassas, referentes ao município de Bauru, e a elaboração de hipóteses sobre mecanismos de ocupação de fitocenoses florestais por espécies savânicas, representaram as principais questões motivadoras do presente estudo, desenvolvido em dois fragmentos de floresta estacional semidecidual (5 ha e 7 ha) mantidos pelo Jardim Botânico de Bauru, que abriga também savana florestada. O material botânico foi coletado a partir de caminhadas ao acaso e em parcelas implantadas durante estudo fitossociológico. Foram encontradas 264 espécies arbustivo-arbóreas, pertencentes a 58 famílias. Dessas espécies 126 foram coletadas apenas na fitocenose florestal, e 66 espécies foram coletadas em ambas as fitocenoses. As duas famílias com o maior número de espécies foram Rubiaceae (25 espécies) e Myrtaceae (21 espécies). Foi realizada análise de similaridade florística, a partir do índice de Jaccard (SJ), entre a floresta do JBMB e outros 11 remanescentes florestais, alguns dos quais, sob influência florística savânica. A riqueza florística dos fragmentos florestais do JBMB sofreu incremento, pela ocupação de espécies savânicas, oriundas da savana florestada contígua. Incêndios pretéritos, além da ocorrência de microambientes distintos, representaram prováveis fatores de facilitação para a invasão dessas espécies savânicas.
Scarce floristic information for Bauru Municipality and the formulation of hypotheses oil occupation mechanisms of forest communities by savanna species represent the main questions that motivated this Study. The research was carried out in two seasonal-semideciduous-forest fragments (5 ha and 7 ha) maintained by Jardim Botanico de Bauru - JBMB (Bauru Botanic Garden), which includes forested savanna as well. The plant material was collected during random walks and in plots installed for a phytosociological study. We found 264 arboreal-shrubby species belonging to 58 families. of these, 126 species were collected exclusively in the forest community, while 66 species were collected in both plant communities. The families Rubiaceae (25 species) and Myrtaceae (21 species) had the highest number of species. A floristic similarity analysis was performed, based on Jaccard's index (S(1)), between the JBMB forest and 11 other forest remnants, some of which showed savanna floristic influence. The floristic richness of the JBMB forest fragments increased due to occupation by savanna species which came from the adjoining forested savanna. Previous fires plus the occurrence of distinct microenvironments were possibly the factors that facilitated the invasion by savanna species.
Scarce floristic information for Bauru Municipality and the formulation of hypotheses oil occupation mechanisms of forest communities by savanna species represent the main questions that motivated this Study. The research was carried out in two seasonal-semideciduous-forest fragments (5 ha and 7 ha) maintained by Jardim Botanico de Bauru - JBMB (Bauru Botanic Garden), which includes forested savanna as well. The plant material was collected during random walks and in plots installed for a phytosociological study. We found 264 arboreal-shrubby species belonging to 58 families. of these, 126 species were collected exclusively in the forest community, while 66 species were collected in both plant communities. The families Rubiaceae (25 species) and Myrtaceae (21 species) had the highest number of species. A floristic similarity analysis was performed, based on Jaccard's index (S(1)), between the JBMB forest and 11 other forest remnants, some of which showed savanna floristic influence. The floristic richness of the JBMB forest fragments increased due to occupation by savanna species which came from the adjoining forested savanna. Previous fires plus the occurrence of distinct microenvironments were possibly the factors that facilitated the invasion by savanna species.
Descrição
Palavras-chave
tension area, savanna species, microclimate, western plateau
Como citar
Acta Botanica Brasilica. São Paulo Sp: Soc Botanica Brasil, v. 22, n. 4, p. 1085-1094, 2008.