Population dynamics of littoral rotifers (Lecane inermis and Lepadella rhomboides) in relation to algal (Chlorella vulgaris) food density
Por:
Sarma S.S.S., Ramírez Alonso M.-I., Nandini S.
Publicada:
1 ene 2006
Resumen:
We cultured two non-planktonic rotifers (L. inermis and L. patella) using four algal food densities (0.1 × 106, 0.2 × 106, 0.4 × 106 and 0.8 × 106 cells mL•1 of Chlorella vulgaris). Under the tested food levels, L. inermis had long (about 15 days) lag phase, while L. rhomboides started to increase its population abundance from the 3rd day onwards. At low food density (0.1 × 106 cells mL•1) L. inermis performed better, while at intermediate concentrations (0.2 × 106 and 0.4 × 106 cells mL•1), L. rhomhoides grew to higher densities. The highest algal density resulted in reduced population growth of both the rotifer species. The rates of population increase (r) of L. inermis and L. rhomboides varied from 0.18 to 0.31 day•1. For both the rotifer species the r was significantly affected by the algal concentration. When the daily rate of population increase was plotted as function of population density, a significant inverse relation was obtained for both the rotifer species. Results have been discussed to explain the differences in the relative abundances both the rotifer species in natural waterbodies with seasonally varying phytoplankton levels. © International Scientific Publications, New Delhi.
Filiaciones:
Sarma S.S.S.:
Laboratorio de Zoología Acuática, División de Investigación y Posgrado, Universidad Nacional Autónoma de México, Campus Iztacala, 54090 Tlalnepantla Edo. de Mexico, Mexico
Ramírez Alonso M.-I.:
Laboratorio de Zoología Acuática, División de Investigación y Posgrado, Universidad Nacional Autónoma de México, Campus Iztacala, 54090 Tlalnepantla Edo. de Mexico, Mexico
Nandini S.:
División de Investigación y Posgrado, UIICSE, Universidad Nacional Autónoma de México, Campus Iztacala, 54090 Tlalnepantla Edo. de Mexico, Mexico
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