RESTINGA FOREST IN CARAVELAS, BAHIA: COMPOSITION, STRUCTURE, AND SIMILARITY
Name: GABRIEL AZEVEDO CARVALHO
Publication date: 24/07/2025
Examining board:
Name |
Role |
|---|---|
| HENRIQUE MACHADO DIAS | Presidente |
| JORGE ANTONIO SILVA COSTA | Examinador Externo |
| LUIS FERNANDO TAVARES DE MENEZES | Examinador Externo |
Summary: This study describes the floristic composition, phytosociological structure, and similarity patterns of arboreal communities on sandy costal ‘restinga’ forests in Caravelas, southern Bahia, with emphasis on comparison with other restinga remnants along the Brazilian coast. Structural sampling was conducted in two forest fragments (areas A and B), using Gentry’s transect method and including all arboreal individuals with DBH 2.5 cm. Data were analyzed using classical phytosociological metrics, diversity indices (Shannon, Simpson, Pielou), and multivariate analyses (NMDS, PCA, UPGMA, HCPC, heatmaps). Additionally, 32 restinga localities across Brazil were evaluated, with strict growth form filtering, taxonomic standardization, and both classical and network-based clustering methods (Louvain), plus Mantel tests with environmental variables. The areas showed high floristic richness (114 species, 76 genera, 35 families) and strong structural heterogeneity, dominated by Protium heptaphyllum, Allagoptera caudescens, and representatives of Myrtaceae and Fabaceae. Comparison revealed approximately 34% shared species but high local exclusivity, reinforcing high beta-diversity typical of restinga. Floristic similarity analyses among localities identified coherent regional groupings, with biogeographic modularity better captured by network approaches. Widespread species acted as connectors between modules, while others were restricted to specific regional blocks. Environmental gradients, especially temperature and precipitation seasonality, explained much of the floristic dissimilarity among sites. The results highlight the oligarchic and heterogeneous nature of restinga forests, the value of combining strict filtering and analytical methods, and the central role of environmental filters and regional connectivity in structuring the flora of these coastal formations.
Keywords: restinga; phytosociology; similarity; biogeography
