Is it possible to evaluate the ecological status of a reservoir using the phytoplankton community?

Author(s)

Aline Martins Vicentin ^[1] ; Eduardo Henrique Costa Rodrigues ^[2] ; Viviane Moschini-Carlos ^[3] ; Marcelo Luiz Martins Pompêo ^[4]

Affiliation

^[1] Universidade Estadual Paulista - Brasil

^[2] Universidade Estadual Paulista - Brasil

^[3] Universidade Estadual Paulista - Brasil

^[4] Universidade de São Paulo. Departamento de Ecologia, Instituto de Biociências - Brasil

• Document type: Journal article
• Source: Acta Limnol. Bras.; v. 30, 2018-11-14.

Abstract

Abstract Aim: The present study aims to evaluate the ecological status of the Broa reservoir through the application of the ecological index Evenness E2 on phytoplankton. Methods Phytoplankton samples from surface were obtained during the dry period (June/2015) in 9 points (P1 to P9), along a longitudinal transect in the reservoir. The qualitative analysis was performed using binocular optical microscope, and the quantitative analysis was performed using the sedimentation chamber method and inverted microscope analysis. The Uniformity Index was calculated on density and richness data. The reference values ​​used in this study were set according to the literature covering 5 classifications (High, Good, Moderate, Low and Bad) for the water quality from Evenness E2 index for phytoplankton, being 1 the maximum value. Results The values ​​observed ranged from 0.1142 in P1 to 0.1468 in P3, being both classified as “Bad”, since values were less than​0.21. Conclusions The result reinforces the sanitary problem of the reservoir, the occurrence of consecutive algae blooms because the amount of nutrients in the region. A massive occurrence of Cyanobacteria was observed, with emphasis on the species Aphanizomenon gracile, which may be related to the adaptive advantages that this class presents on the community in eutrophic environments. Activities in the basin can contribute effectively to the eutrophication process of the reservoir, such as agriculture, sand mining and livestock. The water quality is compromised due to the dense presence of potentially toxic species, reflects of the eutrophication process, pointing commitments for the multiple uses of the reservoir, as well as human and ecosystem health. These processes could be corroborated by the application of the index and indication of poor water quality. (AU)

• FAPESP's process: 16/17266-1 - The European Union Water Framework Directive: applications using the phytoplankton as an environmental discriminator in Brazilian reservoirs
• Grantee: Viviane Moschini Carlos
• Support Opportunities: Regular Research Grants
• FAPESP's process: 14/22581-8 - The European Union's Water Framework Directive: applications to Brazilian reservoirs reality
• Grantee: Marcelo Luiz Martins Pompêo
• Support Opportunities: Regular Research Grants