Prey (Brachionus calyciflorus and Brachionus havanaensis) exposed to heavy metals (Cu and Cd) for different durations and concentrations affect predator's (Asplanchna brightwellii) population growth
Por:
Gama-Flores J.L., Ferrara-Guerrero M.D.J., Sarma S.S.S., Nandini S.
Publicada:
1 ene 2007
Categoría:
Environmental Engineering
Resumen:
In this work, we evaluated the combined effects of heavy metal concentration (CuSO4 and CdCl2 separately, at 0.1, 0.2 and 0.4 mg/L) and exposure time (6 and 24 h) on the population growth of the predatory rotifer Asplanchna brightwellii (predator) via its prey (Brachionus calyciflorus or Brachionus havanaensis). At low Cu concentration, B. calyciflorus stimulated the population growth of its predator as compared to controls. However, under higher Cd concentration and longer exposure time, B. calyciflorus caused lower growth of A. brightwellii. B. havanaensis previously exposed to Cu led to reduced growth of its predator, especially under high metal concentration. Regardless of the treatments, the population growth rates (r) of A. brightwellii varied from 0.11 ± 0.02 to 0.45 ± 0.04 d- 1. The exposure time had significant influence on r of A. brightwellii via only the Cd-exposed prey B. havanaensis. However, regardless of the exposure time, B. calyciflorus exposed to Cu and B. havanaensis exposed to Cd stimulated the growth rate of the predator. In our study the predator was not directly exposed to heavy metals. Therefore, the toxicants acted in an indirect way on A. brightwellii, i. e., the predator's growth was affected through the ingestion of metal-contaminated prey. Copyright © Taylor & Francis Group, LLC.
Filiaciones:
Gama-Flores J.L.:
Doctoral Program, Autonomous Metropolitan University, Campus Xochimilco, Calzada de Hueso, No. 1100, CP 04960, Mexico City, Mexico
Ferrara-Guerrero M.D.J.:
Doctoral Program, Autonomous Metropolitan University, Campus Xochimilco, Calzada de Hueso, No. 1100, CP 04960, Mexico City, Mexico
Sarma S.S.S.:
Division of Research and Postgraduate Studies, National Autonomous University of Mexico, Campus Iztacala, AP 314, CP 54000, Los Reyes, Tlalnepantla, Mexico
Nandini S.:
Division of Research and Postgraduate Studies, National Autonomous University of Mexico, Campus Iztacala, AP 314, CP 54000, Los Reyes, Tlalnepantla, Mexico
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