Original paper
Zooplankton community structure in two Chilean reservoirs
Schmid-Araya, J. M.; Zuñiga, L. R.
Archiv für Hydrobiologie Volume 123 Number 3 (1992), p. 305 - 335
52 references
published: Jan 17, 1992
DOI: 10.1127/archiv-hydrobiol/123/1992/305
ArtNo. ESP141012303002, Price: 29.00 €
Abstract
The zooplankton communities of two Chilean reservoirs were investigated during a year-cycle from September 1983 to November 1984, particularly with regard to the seasonal distribution of species as well as the effect of some environmental factors. Average temperature and oxygen values over the year were similar between the two reservoirs, while high average values of conductivity and chlorophyll-a, together with lower water transparency and extreme changes on the water levels were characteristic to Rungue. A great difference could be seen in the total number of species recorded in both reservoirs, 41 species in Peñuelas (70.7 % rotifers, 22.0 % cladocerans and 4.9 % copepods) compared to 21 species in Rungue (81.0 % rotifers, 9.5 % cladocerans and 9.5 % copepods). Moreover, fluctuating patterns on the average abundance of some zooplanktonic groups, diversity values and species richness, and a massive development of rotifers within a short time were detected in the latter reservoir. This pattern suggests a "disturbance" of the zooplankton community, caused probably by the unstable conditions on the water environment created by the annual water renewal. On the contrary, in Peñuelas average zooplankton abundances and community parameters (species richness and diversity), varied much less and followed the seasonal changes of the year cycle. The predominance of rotifers (few species with high abundances) and low zooplankton diversity values characteristic in Rungue, reflect that this reservoir is either at an early phase on the evolution of its zooplankton community, or reflects a disturbed community when compared to the other reservoir.
Keywords
environment • zooplanktonic • rotifers • Peñuelas • Chile