Diversity, biomass and new records of macroalgae and benthic cyanobacteria in mangroves of the Paranaguá Estuarine Complex - Paraná Fernanda Ribeiro Freitas, João M. Miragaia Schmiegelow, Franciane Pellizzari

Abstract

Mangrove ecosystems are present in sheltered coastal regions of the country, concentrated in estuaries, bays and lagoons. Mangrove forests are subject to the tidal regime and metoceanographic conditions that govern this estuarine system. This work aims to evaluate the diversity, biomass and spatio-temporal distribution of macroalgae and benthic cyanobacteria in different mangroves of the Paranaguá Estuarine Complex. The macrophycological material was collected at four sampling points in Paranaguá Bay. The material was collected during the summer of 2016, sorted and fixed with 4% formalin and in silica gel for subsequent taxonomic analysis, using optical and stereoscopic microscopy of histological sections and analysis of vegetative and reproductive structures. Cryptic specimens will also be analyzed in due course using molecular biology. Biomass was evaluated by percentage of coverage in 0.5m ² squares (n=10). 27 species of macroalgae were recorded, including 16 Rhodophyta, 13 Chlorophyta and 9 species of cyanobacteria. The greater salinity recorded in two of the sampling points seemed to guide the greater diversity observed in them. This taxonomic update of “Bostrychietum” and other associated species can serve as a database and an efficient tool for monitoring sensitive mangrove areas in the face of impacts from port areas and climate change.