Combined effects of heavy metal (Hg) concentration and algal (Chlorella vulgaris) food density on the population growth of Brachionus calyciflorus (Rotifera : Brachionidae)
Por:
Perez, TR, Sarma, SSS
Publicada:
1 mar 2008
Resumen:
The combined effects of two food levels (0.5 X 10(8) and 1.5 X 10(6) cells ml(-1) of Chlorella vulgaris) and five concentrations (0, 0.000625, 0.00125, 0.0025, 0.005 mgl(-1) of HgCl2) of mercury on the population growth of the rotifer Brachionus calyciflorus was evaluated, The growth experiments were conducted for 18 days at 23 +/- 1 degrees C under continuous fluorescent illumination. For each food level - heavy metal combination, we maintained 3 replicates. Our data showed that regardless of food level, increase in the heavy metal concentration in the medium resulted in decreased population growth of B. calyciflorus. At any given heavy metal concentration, B. calyciflorus grown under higher food levels had higher population abundance. The rate of population increase was significantly influenced by both the heavy metal concentration and the algal level. The highest population growth rate (0.435 +/- 0.003 per day) was observed in controlsat 1.5 X 10(6) cells ml(-1). The results of this
Filiaciones:
Perez, TR:
Univ Nacl Autonoma Mexico, Lab Aquat Zool, Div Res & Postgrad Studies, Tlalnepantla 54090, State Mexico, Mexico
Sarma, SSS:
Univ Nacl Autonoma Mexico, Lab Aquat Zool, Div Res & Postgrad Studies, Tlalnepantla 54090, State Mexico, Mexico
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