Algas perif赤ticas a montante e a jusante do local de instala o de tanques-rede em tribut芍rios do reservat車rio de Rosana, Estado do Paran芍, Brasil = Periphytic algae upstream and downstream from the installation of net cages in Rosana reservoir, Parana State, Brazil

作者：Irauza Arroteia Fonseca; Natalia Silveira Siqueira; Liliana Rodrigues

来源：Acta Scientiarum - Biological Sciences, 2009.

• perifiton
• monitoramento ambiental
• aquicultura
• estrutura de comunidade
• periphytic algae
• environmental monitoring
• reservoir
• net cage

Este trabalho objetivou analisar a riqueza e a abundancia de algas perif赤ticas nos rios do Corvo e Guairac芍, tribut芍rios do reservat車rio de Rosana, quando da instala o de tanques-rede. Acreditava-se que o ponto logo 角 frente dos tanques-rede apresentaria menor riqueza e abundancia de algas e que o reservat車rio influenciaria as esta es a jusante dos tanques. Para isso, coletas foram realizadas a montante, em frente e a jusante da instala o de tanques-rede. Independentemente do ambiente, a esta o que apresentou maior riquezafoi 1.000 m a montante. Diminui o na riqueza foi verificada nas esta es 500 m a montante e 500 m a jusante. Quanto 角 densidade, em frente aos tanques, observou-se maior abundancia, seguida pela esta o a 1.000 m a jusante. J芍, nas esta es de amostragem a 500m (a montante e jusante), o n迆mero de indiv赤duos foi inferior 角s demais. Assim, independentemente do ambiente l車tico, constatou-se menor riqueza e abundancia de algas perif赤ticas nas esta es a 500 m dos tanques, o que refor a a importancia de ser realizado obiomonitoramento em uma 芍rea de maior abrang那ncia. This study aimed to analyze the richness and abundance of periphytic algae in Corvo and Guairac芍 rivers, both tributaries of the Rosana reservoir. It was believed that the site just ahead of the installation of net cages presented less richness and abundance of algae. For this, samples were collected 500 and 1,000 m upstream, and downstream and in front of the net cage. Regardless the environment influence, the station that recorded the highest number of species was the 1,000 m upstream. And those that recorded the lowest richness were 500 m upstream and downstream. In front of the tanks was the most abundant, followed by the 1,000 m downstream. On the other hand, the abundance on the 500 m stations was the lowest. Thus, regardless of the lotic environment, less richness and abundance of periphytic algae was found in stations 500 m from the cages, which reinforces the importance of carrying out biomonitoring in an area of greater coverage.