Composition, species richness and patterns of nycthemeral vertical distribution of planktonic cladocereans in a black water Amazonian lake

The aim of this study was to identify patterns of vertical distribution of planktonic cladocerean populations throughout the diel cycle, during the low and high water periods, and its ecological implications for a black water Amazonian lake. Tupé Lake is a black water lake located near the Brazilian city of Manaus. A channel links the lake with the Negro River and its flood pulse. This study was performed in a low-water period (November 2005) and in a high-water period (June 2006). Samples were taken on a 24-hour cycle, every 4 hours and at each meter of the water column, using a Schindler-Pa...