The goal of this study was to evaluate the structural plasticity and distribution of mangrove species in the Estuarine System of Greater Vitória (ESGV). Four areas distributed along the estuary were analyzed. Fringe and basin forests were sampled in each station. Concomitantly to the forest sampling, interstitial salinity was measured in the field, and sediment was collected for analysis of organic matter (OM) content. There was variation in species distribution along the ESGV. Regarding the structural variables, comparative analysis between physiographic types indicated that basin forests were more mature than fringe forests. OM content values were higher in basin forests. There was an inverse relationship between values of mean DBH (Diameter at Breast Height) and live trunk density (R2 = 0.8795, p <0.0001), and a positive relationship between OM content in the sediment and mean DBH (R2 = 0.3215, p = 0.00593). Multivariate analysis evidenced the formation of three groups: the first with higher structural development and dominated by Rhizophora mangle, in areas with higher OM content; the second dominated by Laguncularia racemosa with more impoverished soils; and third group, which aggregated plots subjected to environmental and anthropic stress (like tree cutting), restricted to more urbanized areas.

Keywords: Forest maturity, organic matter, multivariate analysis