Estrutura Do Componente De Regeneração Natural E Arbóreo De Dois Manguezais No Estado Do Paraná

Abstract

RESUMOEsse estudo avaliou comparativamente os parâmetros fitossociológicos da regeneração natural e da vegetação arbórea em dois manguezais distintos no Estado do Paraná, um pertencente à Baía de Paranaguá (manguezal de Antonina) e outro à Baía de Guaratuba (manguezal de Guaratuba). Em cada área, três subáreas foram marcadas e amostradas cinco parcelas de 10 x 10 m para avaliação do componente arbóreo e quinze subparcelas de 1 x 1 m para avaliação da regeneração natural. Avicennia schaueriana, Rhizophora mangle e Laguncularia racemosa exibiram domínio e densidade relativa distintos entre as áreas. Manguezais de Antonina e Guaratuba diferiram tanto na estrutura da regeneração natural como no componente arbóreo. A Análise de Coordenadas Principais (PCoA) mostrou que as diferenças entre as áreas em relação às variáveis abióticas do solo estão fortemente relacionadas com os parâmetros estruturais do componente arbóreo dos manguezais. Os fatores edáficos dos manguezais têm grande importância na separação entre as áreas, já que reflete na capacidade de adaptação das plantas. Palavras-chave: fitossociologia; mangue; salinidade; solo. ABSTRACTWe analyzed the structures of two mangrove forests of Paraná (Brazil) (Antonina Bay and Guaratuba Bay), considering adult trees and regeneration component. In each area, we marked three sub-areas and sampled five plots of 10 x 10 m, equivalent to 0.05 ha to adults trees and fifteen 1 x 1m sub-plots to assess the regeneration component. Avicennia schaueriana, Rhizophora mangle and Laguncularia racemosa exhibited distinct dominance and relative density between the areas. Mangroves of Antonina and Guaratuba differed both in the structure of natural regeneration as the tree component. The Principal Coordinates Analysis (PCoA) show that differences between areas in relation to abiotic variables of soil are strongly related to the structural parameters of trees. The different types of mangrove soil are the most significant factor in the differentiation between the mangrove areas since influences the salinity values and consequent adaptability of plants.

Description of the soil and root biomass of two subtropical mangroves in Antonina and Guaratuba Bay, Paraná State, Brazil

“…Variation in the structure of mangroves, based on diametrical distribution, can also affect local root biomass, as observed in this study. In an earlier investigation, the variation in structure was attributed to differences in the salinity and organic matter content of the soil (Madi et al 2016). It is important to address that the locations of the bays related to open sea is also an important factor that influences the mangrove dynamics, especially tides and, consequently, the vegetation structure.…”

“…Previous studies have shown that these parameters varied between the two study areas, with Antonina Bay having a higher density of individuals than Guaratuba Bay, but with heterogeneous distribution patterns between sampled plots. However, in Guaratuba Bay, several individuals exhibited higher diameters (Madi et al 2016), which interfere in the total basal area. Variation in the structure of mangroves, based on diametrical distribution, can also affect local root biomass, as observed in this study.…”

“…Previous studies of mangrove structure in two areas on the coast of the state of Parana, Brazil, found differences in tree composition (Madi et al 2016). The density of Avicennia schaueriana and the density and dominance of Laguncularia racemosa and Rhizophora mangle were the main features that distinguished the tree structure of these two mangroves.…”

“…The density of Avicennia schaueriana and the density and dominance of Laguncularia racemosa and Rhizophora mangle were the main features that distinguished the tree structure of these two mangroves. Furthermore, these differences were found related to the higher salinity of Guaratuba Bay and the higher organic matter content of Antonina Bay (Madi et al 2016). Based on this information, this study evaluated the relationship between edaphic conditions and root biomass in the both mangrove areas to contribute with better understanding of relationships between soil and vegetation.…”

“…These soils include Gley and Organosoils (Embrapa 1978) and are predominately comprised of fine particles, such as silt and clay, high levels of organic matter and soluble salts due the presence of seawater (Cintron & Schaffer-Novelli 1983). The structural and chemical compositions of the soil are important factors in determining the density and abundance of mangrove tree species (Madi et al 2016).…”