Feeding and filtration rates of zooplankton (rotifers and cladocerans) fed toxic cyanobacterium (Microcystis aeruginosa)
Por:
Perez-Morales, A, Sarma, SSS, Nandini, S
Publicada:
1 nov 2014
Resumen:
Microcystis aeruginosa is generally dominant in many Mexican freshwater
ecosystems interacting with zooplankton species. Hence, feeding and
filtration rates were quantified for three cladoceran (Daphnia pulex,
Moina micrura and Ceriodaphnia dubia) and three rotifer species
(Brachionus calycifiorus, Brachionus rubens and Plationus patulus) using
sonicated M. aeruginosa alone or mixed with Scenedesmus acutus in
different proportions (25, 50 and 75%, based on cell density), offering
a combined initial density of 100,000 cells.ml(-1). All the three
cladoceran species ingested M. aeruginosa (100-300 cells ind(-1)
min(-1)) when fed exclusively with cyanobacterium. When green alga
offered as exclusive diet, the number of cells ingested by the tested
cladocerans varied from 80 to 400 cells ind(-1) mind. Compared to
cladocerans, rotifers in general consumed much lower quantity (< 200
cells ind(-1) min(-1)) of M. aeruginosa and S. acutus. The filtration
rate for Daphnia pulex was inversely related to the proportion of green
alga in the diet. For other tested cladocerans, no such clear trend was
evident. In mixed treatments containing M. aeruginosa, the filtration
rate of Daphnia was highest (about 220 mu l ind(-1) min(-1)) when the
medium contained 75% of S. acutus. Among the rotifer species, P patulus
filtered highest volume (100 mu l ind(-1) min(-1) from mixed diets
containing higher proportions (50 or 75%) of M. aeruginosa. Thus, there
were species-specific differences in the filtration and feeding rates of
zooplankton when offered mixed diets of green algae and toxic
cyanobacteria. These probably explain the coexistence of different
zooplankton species in Microcystis-dominant waterbodies.
Filiaciones:
Perez-Morales, A:
Univ Nacl Autonoma Mexico, Div Invest & Estudios Posgrad, Lab Zool Acuat, Tlalnepantla 54090, Estado De Mexic, Mexico
Sarma, SSS:
Univ Nacl Autonoma Mexico, Div Invest & Estudios Posgrad, Lab Zool Acuat, Tlalnepantla 54090, Estado De Mexic, Mexico
Nandini, S:
Univ Nacl Autonoma Mexico, Div Invest & Estudios Posgrad, Lab Zool Acuat, Tlalnepantla 54090, Estado De Mexic, Mexico
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