Composição, riqueza e índices ecológicos do fitoplâncton do lago Bolonha (Belém, Pará) / Composition, richness and ecological index of phytoplankton of lake Bolonha (Belém, Pará)

Abstract

Composição, riqueza e índices ecológicos do fitoplâncton do lago Bolonha (Belém, Pará) Composition, richness and ecological index of phytoplankton of lake Bolonha (Belém, Pará

Ecological indexes and phytoplankton structure of urban reservoirs supplied by estuarine waters and under the effects of seasonality (Belém, Pará, Brazil)

“…Although this study did not observe a significant temporal variation of phytoplankton, other studies [30,54,55] verify the existence of a variation in phytoplankton density, with the highest values occurring in the less rainy season, due to the interaction of factors that influence the phytoplankton development, such as the entry of light into the water column, which is greater in the dry months [14].…”

“…Spearman's correlation evidenced seasonality acting on the dynamics of the reservoirs, where precipitation was negatively related to temperature (rs = -0.64) and average wind speed (rs = -0.96), in addition to rains, winds are positively related to the temperature (rs = 0.67) and salinity (rs = 0.61), since the highest temperatures and strongest winds occur in the less rainy season (Table 2). Turbidity and transparency are inversely proportional (rs = -0.73) and are directly related to seasonality, as rainfall influences the suspension of solids in water [14]. While salinity is positively related to electrical conductivity (rs = 0.83), due to the greater availability of ions in water (Table 2).…”

“…In this scenario, sewage is discharged without prior treatment into rivers and the contaminated water is the main cause of several processes of ecological imbalance due to the loss of its quality and biodiversity [10]. The reservoirs of this supply system are dominated by aquatic macrophytes and their waters are eutrophic, with records of cyanobacteria blooms, which makes them unsafe for human consumption [11][12][13][14]. Due to the increasing scarcity of water, existing aquatic environments must be monitored in order to ensure safe water for supply and to predict processes that impact these environments and may endanger their ecological integrity.…”

Effect of seasonality and estuarine waters on the phytoplankton of the Guamá River (Belém, Amazon, Brazil)

“…The variation in phytoplankton density in the Guamá River followed a seasonal pattern, with the lowest values occurring in the rainier months. Several studies point to lower phytoplankton concentration in rivers (Paiva et al 2006, Sousa et al 2013, Rocha Neto et al 2017, Wang et al 2021 and reservoirs (Costa et al 2010, Rodrigues et al 2018 in the rainiest periods, since the interaction of rain and suspended solids in this period causes the attenuation of light in the aquatic environment (Sousa et al 2020), and therefore, interferes with the development of phytoplanktonic organisms, since they are entirely dependent on the availability of light (Stumpner et al 2020).…”