Composition of Microphytoplankton of an Estuarine Amazon River, Pará, Brazil

Abstract

This work aims to describe the composition, relative abundance and frequency of occurrence of microphytoplankton in the Arienga River, determined from the analysis of ten samples collected in the rainy and dry seasons (May and September 2009 respectively), during five stations, using a plankton net with a mesh size of 20m. In the period studied, the rainfall showed an atypical behavior, compared to the average of the last ten years for the region, as pH and temperature did not undergone changes. A total of 128 species were identified, belonging to divisions: Dinophyta (0.78%), Chrysophyta (0.78%), Cyanobacterium (12.50%), Chlorophyta (26.56%), and Bacillariophyta (59.38%). Of Genres found, 17 had 100% of representativeness at in both fenods. It was possible to confirm two large groups, suggesting that the rainfall regime was the main controller factor of phytoplankton composition and spatial variation of species along the Arienga River. The phytoplankton diversity was considered characteristic of the Amazon region; therefore, it is considered that the human action did not affect the phytoplankton community of the Arienga River to date.

Spatial and seasonal variation of microphytoplankton community and the correlation with environmental parameters in a hypereutrophic tropical estuary - Maranhão - Brazil

“…The dominance of diatoms is common in estuarine systems due to their euryhaline nature (SENA et al, 2015) and it is correlated directly with the silicate content, since the major source of silica is from the continent and the diatoms frustules have silica in their composition. In estuaries of Maranhão, the predominance of that group occurs in over 80% of the phytoplankton composition (FERREIRA-CORREIA et al, 2004;RODRIGUES;CUTRIM, 2010) and when eutrophication happens, blooms of diatoms become more frequent due to the wide availability of nutrients and high salinity (MATOS et al, 2011).…”

“…Under these conditions, the local phytoplankton community consists mostly of centric taxa classified as rare and occasional. That is due to the high hydrodynamic environment that can reach areas far from the mouth, that are considered lentic zones (PAIVA et al, 2006;SOUSA et al, 2008;REZENDE et al, 2015;SENA et al, 2015).…”

Saúde pública e saúde coletiva: contribuições para o bem-estar da comunidade 2

“…Embora os cursos d'agua de águas brancas amazônicas sejam pouco estudados se sabe que as diatomáceas dominam a composição, diversidade e abundância e, juntamente, com os fitoflagelados contribuem para as altas densidades de microalgas (PAIVA et al, 2006;SOUSA et al, 2015;SENA et al, 2015;MATOS et al, 2016a;ROCHA NETO et al, 2016;PIRES et al, 2024).…”

“…Por outro lado, P. coronalis é uma espécie típica das águas brancas de baixas salinidades, sendo encontrada desde a Baía do Vieira, Afuá-PA (SOUSA et al, 2015), Baía do Guajará-PA (PAIVA et al, 2006), Rio Arienga-PA (SENA et al, 2015), Foz do Rio Guamá-PA (MONTEIRO et al, 2011;PIRES et al, 2024)…”

Benthic macroinvertebrates as bioindicators of environmental quality of Pará River estuary, a wetland of Eastern Amazon

“…Effects of environmental impacts on aquatic biota at the Vila do Conde Industrial Pole were evaluated by some studies addressing plankton (phyto-and zooplankton) and ichthyofauna. Regarding plankton, changes in density of organisms, and a higher frequency of impacting species were observed in the areas closest to the port system (SENA et al, 2015;COSTA et al, 2016a;2016b;PINHEIRO et al, 2019). In the ichthyofauna, in places close to the IPC, there was a reduction in the diversity of species and food guilds (VIANA; FRÉDOU; FRÉDOU, 2012; VIANA; FRÉDOU, 2014), in addition to a higher incidence of individuals with histopathological damage (VI-ANA et al, 2013).…”