Menezes Vc, Bueno Nc, Rodrigues Lc
Programa de Pós-graduação em Conservação e Manejo de Recursos Naturais, Universidade Estadual do Oeste do Paraná - UNIOESTE, Rua Universitária, 2019, Jardim Universitário, CEP 85819-110, Cascavel, PR, Brazil.
Braz J Biol. 2013 May;73(2):279-90. doi: 10.1590/S1519-69842013000200008.
The work aimed to show variations in the composition and structure of the phytoplankton community at high water and low water in Iguaçu Falls, Iguaçu River and to examine the influence of these waterfalls and environmental variables on the community. Phytoplankton samples were taken monthly during a year from two sampling stations in the Iguaçu River. A total of 408 taxa were identified, with Bacillariophyceae being the most strongly represented group. A large differentiation in the composition of the phytoplankton was observed between the sampling stations. The total richness and density of the phytoplankton groups was very low in both sample locations, as well as the Shannon diversity index, but the evenness value was generally high. No significant seasonal and spatial difference in the studied features of the phytoplankton community was seen. But, significant seasonal differences were observed when the density and richness of the algae classes were assessed separately. The heterogeneity of the Iguaçu River's characteristics between the sampling sites caused no significant spatial differentiation in the features of the phytoplankton community. However, the seasonal variation of the climatic conditions has significantly influenced the composition and structure of the community in the Iguaçu River.
这项工作旨在展示伊瓜苏瀑布、伊瓜苏河涨水期和枯水期浮游植物群落的组成和结构变化，并研究这些瀑布和环境变量对群落的影响。在一年时间里，每月从伊瓜苏河的两个采样站采集浮游植物样本。共鉴定出408个分类单元，其中硅藻纲是占比最大的类群。在采样站之间观察到浮游植物组成存在很大差异。两个采样点浮游植物类群的总丰富度和密度都很低，香农多样性指数也很低，但均匀度值普遍较高。浮游植物群落的研究特征没有明显的季节和空间差异。但是，当分别评估藻类类群的密度和丰富度时，观察到了显著的季节差异。采样点之间伊瓜苏河特征的异质性并未导致浮游植物群落特征出现显著的空间分化。然而，气候条件的季节变化对伊瓜苏河群落的组成和结构产生了显著影响。
