Acute toxicity of Microcystis spp. (Cyanobacteria) bloom on Moina minuta (Cladocera) in a tropical reservoir, Northeastern Brazil

Authors

  • Mauro Cesar Palmeira Vilar Bacharel em Ciências Biológicas (UFRPE) Mestrando em Ecologia (UFRPE)
  • Cristiane Maria Varela de Araújo-Castro Professor Adjunto I Universidade Federal Rural de Pernambuco
  • Ariadne do Nascimento Moura Professor Associado IV Universidade Federal Rural de Pernambuco

DOI:

https://doi.org/10.5132/eec.2014.01.012

Abstract

Worldwide cyanobacterial blooms have been registered, where harmful species dominance is associated to producing of toxic compounds (cyanotoxins) with adverse effects on several organisms. Acute toxicity of crude extracts from Microcystis bloom occurring in Mundaú reservoir was evaluated by bioassays with the neotropical Cladocera Moina minuta. Samples were taken in the reservoir during the rainy (April/2012) and dry season (September/2012). Cyanobacterial analyses were performed by identification on optical microscopy and direct counting using an inverted microscope. Bloom samples were frozen, lyophilized and re-suspended in deionized water for preparation of extracts. Tests with the cladoceran were carried out in test tubes with different concentrations of the crude extract, diluted in 10 mL reconstituted water. In both rainy and dry periods, densities of Microcystis spp. were above 15x103 ind mL-1. Microcystin concentrations in the extracts were 0.70 (+ 0,009) (rainy season) and 0.69 (+ 0,005) (dry season) μg g-1. The LC50 (48h) of crude extract for both rainy and dry periods was 160 (100 – 255) and 72 (4 – 1113) mg L-1, respectively. These results indicated that extracts of Microcystis spp. were acutely toxic to M. minuta population with suggesting that such events represent potential toxicity to zooplankton.

Author Biographies

Mauro Cesar Palmeira Vilar, Bacharel em Ciências Biológicas (UFRPE) Mestrando em Ecologia (UFRPE)

Universidade Federal Rural de Pernambuco

Departamento de Biologia

Discente do Programa de Pós-graduação em Ecologia/UFRPE 

Cristiane Maria Varela de Araújo-Castro, Professor Adjunto I Universidade Federal Rural de Pernambuco

Professor Adjunto I

Laboratório de Ecofisiologia e Comportamento Animal

Departamento de Morfologia e Fisiologia Animal

Universidade Federal Rural de Pernambuco

 

Ariadne do Nascimento Moura, Professor Associado IV Universidade Federal Rural de Pernambuco

Professor Associado IV

Laboratório de Ficologia

Área de Botânica

Departamento de Biologia

Universidade Federal Rural de Pernambuco

Downloads

Published

17-11-2014

How to Cite

Vilar, M. C. P., Araújo-Castro, C. M. V. de, & Moura, A. do N. (2014). Acute toxicity of Microcystis spp. (Cyanobacteria) bloom on Moina minuta (Cladocera) in a tropical reservoir, Northeastern Brazil. Ecotoxicology and Environmental Contamination, 9(1), 93–98. https://doi.org/10.5132/eec.2014.01.012

Issue

Section

Original Articles