Influência da chuva sobre a comunidade de cianobactérias fitoplanctônicas de uma represa subtropical

Abstract

Tropical and subtropical regions currently have a great diversity of organisms, due to their climate, availability of nutrients and favourable living conditions in which diferente species can live in mutual and symbiotic relationships. Cyanobacteria can adapt to many habitats, including terrestrial, marine, freshwater and ice environments. A serious problem we are currently seeing is the large-scale proliferation of this organismo in aquatic environments, especially in freshwater environments with little current. This environmental problem affects the environment through some species of cyanobacteria that can produce toxins. Based on this recurrent environmental concern, this study aimed to verify the influence of rainfall on the phytoplankton cyanobacteria community in the UTFPR-DV pound and to produce teaching material on the subject. Four collections were carried out (summer rain and dry; winter dry and spring rain) in 2023 and 2024. A qualitative and quantitative study of the community was carried out. Eight cyanobacterial taxa were identified, with Synechocaceae being the most numerous family. Synechococcus nidulans, Synechocystis aquatilis and Aphanocapsa delicatissima were the most abundant species in terms of number of individuals. The community varied mainly in response to seasonality, but the climatic factor rainfall influenced both the density of species and the richness of the community. Two potentially toxic taxa were recorded. The educational game Cyanogame was produced.