Effect of crude extracts from cyanobacterial blooms in Lake Texcoco (Mexico) on the population growth of Brachionus calyciflorus (Rotifera)
Por:
Zamora Barrios, Cesar Alejandro, Nandini, S., Sarma, S. S. S.
Publicada:
1 dic 2017
Categoría:
Toxicology
Resumen:
Unlike temperate regions, tropical ecosystems are characterized by high
temperatures (>18 degrees C) all year, promoting blooms of cyanobacteria
which often produce secondary metabolites toxic to zooplankton. Nabor
Carillo and the Recreational Lake are part of the saline, Lake Texcoco,
in Central Mexico which is filled nowadays with treated waste water.
Both water bodies are dominated by Planktothrix, Anabaenopsis, Spirulina
and Microcystis. In this study we present the concentration of
microcystins in these waterbodies over an annual cycle. We also
evaluated the chronic effects of cyanobacterial crude extracts from both
lakes on two clones of the rotifer Brachionus calyciflorus, one from
Nabor Carrillo Lake and the other from a canal in the shallow, Lake
Xochimilco. The experiments on population growth were performed,
beginning with 10 individuals per container for each of the following
treatments: control (no crude extract), concentrated crude extract, and
diluted crude extract (50:50) with moderately hard water and Chlorella
vulgaris in a concentration of 0.5 x 10(6) cells ml(-1). The cyanotoxin
levels were measured using an ELISA test and ranged between 0.20 and 2.4
mu gL(-1) in the lake water. The results showed that the Recreational
Lake extracts were more toxic, killing the rotifers in less than five
days. The r values ranged from -1.74 to 0.48 in the presence of the
crude extracts and 0.16 and 0.24 in the controls. The results have been
discussed with emphasis on the importance of conducting regular studies
to test ecotoxico-logical impacts of cyanobacterial blooms in tropical
waters. (C) 2017 Elsevier Ltd. All rights reserved.
Filiaciones:
Zamora Barrios, Cesar Alejandro:
Univ Nacl Autonoma Mexico, Div Res & Postgrad Studies, Lab Aquat Zool, Campus Iztacala,Av Los Barrios 1, Tlalnepantla 54090, State Of Mexico, Mexico
Nandini, S.:
Univ Nacl Autonoma Mexico, Div Res & Postgrad Studies, Lab Aquat Zool, Campus Iztacala,Av Los Barrios 1, Tlalnepantla 54090, State Of Mexico, Mexico
Sarma, S. S. S.:
Univ Nacl Autonoma Mexico, Div Res & Postgrad Studies, Lab Aquat Zool, Campus Iztacala,Av Los Barrios 1, Tlalnepantla 54090, State Of Mexico, Mexico
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