INVESTIGADORES
IZAGUIRRE Irina
artículos
Título:
Comparative study of the planktonic communities of three lakes of contrasting trophic status at Hope Bay (Antarctic Peninsula).
Autor/es:
IZAGUIRRE, I.; ALLENDE, L.; MARINONE, M.C.
Revista:
JOURNAL OF PLANKTON RESEARCH
Editorial:
Oxford University Press
Referencias:
Año: 2003 vol. 25 p. 1079 - 1097
ISSN:
0142-7873
Resumen:
Three water bodies of contrasting trophic status located at Hope Bay (Antarctic Peninsula) were
studied during the summer of 1999, analysing all of their planktonic communities (zooplankton,
phytoplankton and bacterioplankton) and their main limnological features. Important differences
associated with their trophic conditions were found among lakes. At one extreme of the gradient, in
the most oligotrophic lake (Lake Chico), the nektobenthic copepod Boeckella poppei and the rotifer
Philodina gregaria were dominant in the open waters, and copepods presented a single reproductive
event (univoltine life cycle); phytoplankton exhibited the lowest densities, dominated by nanoplanktonic
Chrysophyceae and picocyanobacteria. In the meso-eutrophic Lake Boeckella, B. poppei, the
dominant zooplankter, exhibited a multivoltine life cycle; phytoplankton were mainly represented by
nanoplanktonic species of Volvocales, alternating with flagellate Chrysophyceae, and a great abundance
of picocyanobacteria. In the hypertrophic Pingüi Pond, zooplankters were exclusively
represented by bdelloid rotifers and ciliates; phytoplankton samples included some strictly planktonic
species (Volvocales), a great proportion of picocyanobacteria and many typically benthic species (oscillatorians
and diatoms) due to the shallowness of the water body. Bacterioplankton densities did not
show important differences among lakes, but fluctuations, probably associated with a top-down
control, were observed in the hypertrophic pond. This paper constitutes the first survey concerning all
the planktonic compartments of water bodies of different trophic status at Hope Bay, describing the
relative contributions of autotrophic and heterotrophic components to their food webs