Fitoplâncton de uma Lagoa de Estabilização no Nordeste do Brasil

Abstract

The study of phytoplanktonic organisms has grown in recent times, as a consequence of its importance in several aquatic ecosystems, both in continental and marine environments. In stabilization ponds, for example, they act in the biological treatment of sewage. These ponds are an eutrophic environment, characterized by a considerable growth of phytoplankton. To study the phytoplankton composition in such ponds, samples were collected in a facultative pond in a sewage treatment station, located in Barbalha (Ceará State, Brasil), from March/2006 to January/2007. The samples were analyzed in vivo and fixed, then indexes of abundancy, frequency, diversity and equitability were calculated. Cyanophyta, Euglenophyta, Bacillariophyta and Chlorophyta species were identified. The most abundant species and present in all samples were Planktothrix isothrix (Skuja) Komárek et Komárková. and Microcystis aeruginosa (Kütz) Kütz., which are both toxic species. In both dry and rainy seasons, variation of the phytoplankton composition wasn't observed and the high presence of P. isothrix resulted in a low diversity. The phytoplankton groups observed are typical of eutrophic environments.

Cyanobacteria Occurrence in Photosynthetic Stabilization Ponds

“…The genera of cyanobacteria found in the present study differ little from those recorded by Aquino (2010) and Aquino (2011) Six species of cyanobacteria were common in the ten studied ponds: M. tenuissima, Aphanocapsa sp, Lyngbya sp, Pseudanabaena sp, Microcystis sp e Spirulina sp. On average, M. tenuissima appeared more, suggesting that this species best adapts to the hypereutrophic environment of the ponds.…”

Spatial and temporal variation of phytoplankton in subtropical stabilization ponds

“…), c-strategist, in both ponds, as observed by Aquino et al (2011). These organisms are abundant in shallow water bodies with higher concentration of nutrients (Padisák et al, 2009).…”

“…However, it should be considered that lower biodiversity may decrease the magnitude and stability of the ecosystem processes, such as the use of resources and productivity (Cottingham et al, 2001;Ptacnik et al, 2008). Delazari-Barroso et al (2009) had reported such event in Brazil, with 38 taxa in the polishing ponds; Aquino et al (2011) also identified 22 phytoplankton taxa in the facultative pond. Cyanobacteria had a major contribution regarding both richness (mean of 9 taxa per sample) and phytoplankton abundance (high contribution of Pseudanabaena mucicola in February 2012), which may be common in this type of environment, where it prevails over other phytoplankton groups (Furtado et al, 2009).…”

“…Palmer (1969), Mara et al (1983) and Pearson et al (1987) were pioneers at studying phytoplankton community in stabilization ponds with focus on the ponds operation and maintenance. In Brazil, other researchers have developed studies with this type of environment, including the northeastern region, with Ceballos et al (1998), Paraíba State; Cavalcanti et al (2010), Pernambuco State; Aquino et al (2010) and Aquino et al (2011), Ceará State. Still, the southeast region counts with a research by Barroso et al (1997) and…”

Variação Temporal Do Fitoplâncton Em Um Rio Tropical Pré-Amazônico (Rio Pindaré, Maranhão, Brasil).

“…Além disso, a comunidade fitoplanctônica é amplamente utilizada em estudos de biomonitoramento de corpos hídricos (CARVALHO, 2003) em função da sua capacidade ecológica em responder rapidamente a qualquer estímulo externo, como por exemplo, aos processos de poluição e contaminação do meio aquático. Estes organismos são muito utilizados como bioindicadores da qualidade ambiental (AQUINO et al, 2011;LOPES, 2007;PEREIRA, 2007).…”