Planktonic rotifer feeding in hypertrophic conditions
Por:
Miracle M.R., Vicente E., Sarma, SSS, Nandini S.
Publicada:
1 mar 2014
Resumen:
We studied the role of rotifers as grazers in hypertrophic waters, dominated by poorly edible filamentous and colonial cyanobacteria. Population growth of Anuraeopsis fissa and Brachionus angularis, from hypertrophic lake Albufera in Valencia, was followed for 15 days in three treatments of different food size fractions: (a) 0-15µm (lake water filtered through 15µm nytal sieve), (b) 0-3µm (15µm lake water filtrate filtered through 3µm nuclepore filter), and (c) 3-15µm (re-suspension, in absolute filtered lake water, of the seston collected on the 3µm filter, after passing lake water previously filtered through 15µm). None of the species grew when fed the food size fraction of 3-15µm that contained a large proportion of filamentous and colonial cyanobacteria. A. fissa showed highest growth parameters when fed the <3µm food size fraction, which was mainly composed of bacterioplankton, but much reduced growth on the whole <15µm seston fraction. On the other hand, B. angularis showed highest growth on the whole <15µm seston fraction and a moderate growth when fed only on the <3µm seston fraction. Clearance, ingestion, and assimilation rates were measured with 3H-thymidine plus 3H-leucine-labeled lake bacteria community, suspended in the 15 and 3µm lake water filtrates. B. angularis had higher rates than A. fissa, and both had higher rates when suspended in the <3µm seston fraction. Our results confirm that bacteria are the dominant food source for both species in this hypertrophic lake, but clear niche differences separate them. A. fissa is more dependent on smaller food particles and is more sensitive to dense blooms of colonial and filamentous cyanobacteria than B. angularis. The distinct feeding abilities of these species shape their differential distributions in space and time. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Filiaciones:
Miracle M.R.:
Departament de Microbiologia i Ecologia and ICBiBE, Universitat de València, Burjassot, Valencia, Spain
Vicente E.:
Departament de Microbiologia i Ecologia and ICBiBE, Universitat de València, Burjassot, Valencia, Spain
Sarma, SSS:
Univ Nacl Autonoma Mexico, Lab Aquat Zool, Tlalnepantla, Mexico
Nandini S.:
Univ Nacl Autonoma Mexico, Lab Aquat Zool, Tlalnepantla, Mexico
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