Estrutura do bosque de manguezal do Rio Camaratuba, Paraíba, Brasil

Abstract

Mangroves are tropical and subtropical ecosystems found across 118 countries and territories, covering approximately 137,600 km². These environments mainly develop in estuaries, which can be divided into three zones: upper, middle, and lower estuary. They include characteristic features such as mudflats, salt flats, and mangrove forests, which contain fringe and interior areas. Salinity is a critical environmental factor, acting as a stress agent in this ecosystem, influencing the development, distribution, growth, and productivity of species. In Brazil, although mangrove species diversity is relatively low, with species like Rhizophora mangle L., Laguncularia racemosa (L.) C.F.Gaertn., Avicennia germinans (L.) L., and Avicennia schaueriana Stapf & Leechm. ex Moldenke standing out, the country exhibits a broad structural variation and species distribution along its coast. Phytosociological studies have been conducted to analyze the composition and dynamics of mangrove forests in relation to environmental factors. This study aimed to describe the structure of the mangrove forests in the Camaratuba River, Paraíba, comparing estuarine regions and forest zones, and testing the hypothesis that structural parameters are negatively related to salinity, using the plot method. The species found were R. mangle (89.16%), L. racemosa (6.40%), and A. schaueriana (4.43%). The recorded averages were: density (1,200-2,150 ind/ha); DBH (4.36-20.50 cm); basal area (3.62-42.75 m²/ha); height (4.05-7.65 m); and above-ground biomass (25.12-511.21 Mg/ha). No significant differences were observed between the estuarine regions due to the uniformity of the area associated with the small size of the estuary. However, the fringe forest presented significantly higher averages of DBH, basal area, height, and above-ground biomass, due to higher salinity. Therefore, this study, with results to be published in a scientific article in the journal Acta Botanica Brasilica, contributes to filling the information gap on mangrove structure in Paraíba, proving relevant for future phytosociological research as well as for conservation and sustainable management efforts.