Caracterização das formações vegetais da restinga da Princesa, Ilha de Algodoal - Pará

Abstract

The vegetation communities of a sandy coast (restinga) of Pará state, Brazil, were studied at Princesa Beach, Algodoal Island, locatede at 00o35’03’’- 00o38’29’’S and 47o31’54’’-47o34’57’’ W.Gr., with the objective of characterizing the vegetation formations. Along transects in the direction offshore-mainland, the vegetation communities were identified and their allied geomorphologic series observed. The floristic composition of each vegetation type was evaluated using random walk collection of the flowering and/or fruiting species. The number of species found in all vegetation communities was 241. The structure of the vegetation was evaluated using the phytosociological method of quadrats. The floristic composition of the predominant herbaceous associations varied between the dry and rainy seasons, but the species with the highest importance value were the same in both seasons. For these communities Cyperaceae and Gramineae were the most important families in both seasons, while for communities which are predominated by trees and shrubs, Myrtaceae was dominant. The vegetation communities with trees and shrubs showed a low index of floristic diversity and equitability, owing to low species richness and the concentration of many specimens within a restricted group of botanical species. The studied vegetation associations showed a structure and constitution that justifies considering them distinct. The floristic similarity varied from 15 to 45%.