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Vol. 53, 2014
Rainfall influence on species composition of the ciliate
community inhabiting bromeliad phytotelmata
Paulo
Roberto Bressan Buosi1*, Laura Roberta Pinto Utz2,
Bianca Ramos de Meira1, Bianca Trevizan Segóvia da Silva1,
Fernando Miranda Lansac-Tôha1, Fabio Amodeo Lansac-Tôha1
and Luiz Felipe Machado Velho1
1Graduate
Program in Ecology of Continental Aquatic Environments, Universidade
Estadual de Maringá, Av. Colombo, 5790, Maringá, Paraná 87020-900,
Brazil
2Graduate Program in Zoology, Pontificia Universidade
Católica do Rio Grande do Sul, Av. Ipiranga 6681, Porto Alegre, Rio
Grande do Sul 90619-900, Brazil
Abstract
Background: In this paper, we
verified the changes in species composition of the ciliate community
inhabiting phytotelmata of tank bromeliads in response to seasonality
(rainfall). Plants were located at several heights of a great rocky
wall on the left bank of the Parana River, southern Brazil. We also
assessed if the heights of the plants in relation to the river
influence the ciliate species composition. Thus, samplings were
performed in the dry and rainy seasons, in three layers of the rock
walls (lower, middle, and upper), with a total of 72 samples in both
periods.
Results: A relative high number of species and a
predominance of hymenostomatids were observed in the sampled plants.
Among the recorded species, about 35% occurred exclusively in the dry
season. The detrended correspondence analysis demonstrated that the
ciliate community changed substantially due to rainfall. However, there
was no distinctness in species composition among the strata. In
contrast to expectations, the number of species recorded in the dry
season was greater than that recorded in the rainy season, refuting the
hypothesis that the precipitation volume favors an increase in the
number of species.
Conclusions: The rainfall is,
undoubtedly, the main factor structuring the community and determining
the ciliate species composition in the phytotelmata of the bromeliads.
We found that the closeness of the plants with the river is also an
important factor for the structuration of the community, due to the
dispersion of organisms from the river to the tanks. The occurrence and
predominance of planktonic species in the plants at the lower stratum
and soil species at the higher stratum indicates a great influence of
the neighboring environments on the ciliate community inhabiting the
phytotelmata.
Key words: Ciliates; Protozoa; Seasonality;
Species composition; Tank bromeliads.
*Correspondence: E-mail: paulobuosi@hotmail.com
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