Análise quali-quantitativa das populações algáceas de um trecho recifal na praia de Boa Viagem, PE

Abstract

This study analyzed the structure of seaweed populations of Boa Viagem beach (08o 05’26”S; 34o 52’55”W e 08o 08’52”S; 34o 54’23”W) in Recife, Pernambuco state, Brazil, through the phytosociologic relevé method. Two locations were selected from the reef plateau surface on the intertidal zone: location 1 was placed on the exposed side of the reef plateau and location 2 was placed on the sheltered side of the plateau. Samples were collected in a rainy period (April 2002) and in a dry period (November 2003). The following parameters were determined: number of taxa, coverage area of each species (Ri), total coverage area (Rt), diversity (H’), evenness (J), species reproductivity (Gi) and density of reproduc- tion for each “relevé” (dG). Forty-nine species were identified, being 33 Rhodophyta, five Ochrophyta and 11 Chlorophyta. The lowest total coverage area observed was 87.55% on location 1 during the dry season and the greatest was 345.35% on location 2 during the dry season. Diversity values varied 2.22–2.62 during the two periods and evenness varied 0.29–0.75. The results indicate the seaweed populations of Boa Viagem present intermediary diversity. The number of individuals among the different species was fairly balanced, except for the sheltered side of location 2 in the rainy season.