Exposure time-dependent cadmium toxicity to Moina macrocopa (Cladocera): A life table demographic study
Por:
Gama-Flores J.L., Sarma S.S.S., Nandini S.
Publicada:
1 ene 2007
Resumen:
In this work, we quantified the life table demographic responses of Moina macrocopa daily exposed to three concentrations, 0, 0.08, 0.16, and 0.32 mg l-1 of CdCl2 for 3, 6, 12, and 24 h. These cadmium levels represented 10-50% of the median lethal concentration known for M. macrocopa. In general, increase in CdCl2 concentration and increase in the exposure time had a negative impact on the both survivorship and reproduction variables of M. macrocopa. The survivorship curves showed drastic mortality of M. macrocopa exposed for 24 h per day at all three concentrations used. The survival of animals was distinctly lower than in controls for the 3-h exposure at 0.08 mg l-1 of CdCl2. The cladocerans ceased to reproduce when exposed to 0.32 mg l-1 CdCl2 for 6 h or longer. Depending on the heavy metal concentration and the duration of exposure, the average lifespan, net reproductive rate, generation time, and the rate of population increase varied from 3 to 10 days, 1 to 30 offspring female -1, 4 to 8 days, and -0.20 to +0.59 day-1, respectively. Even the lowest CdCl2 concentration for an exposure time of 3 h had an adverse effect on M. macrocopa, which suggested the importance of including pulsed exposure times in ecotoxicological evaluations. © 2007 Springer Science+Business Media B.V.
Filiaciones:
Gama-Flores J.L.:
Doctoral Programme, Autonomous Metropolitan University, Campus Xochimilco, Calzada del Hueso No. 1100, Villa Quietud, Mexico City CP 04960, Mexico
Division of Research and Postgraduate Studies, National Autonomous University of Mexico, Campus Iztacala, Av. de los Barrios no. 1, Los Reyes, Tlalnepantla, State of Mexico CP 54090, Mexico
Sarma S.S.S.:
Division of Research and Postgraduate Studies, National Autonomous University of Mexico, Campus Iztacala, Av. de los Barrios no. 1, Los Reyes, Tlalnepantla, State of Mexico CP 54090, Mexico
Nandini S.:
UIICSE, National Autonomous University of Mexico, Campus Iztacala, Av. de los Barrios no. 1, Los Reyes, Tlalnepantla, State of Mexico CP 54090, Mexico
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