Fish fauna associated to aquatic macrophytes Eichhornia azurea (SW.) Kunth. and Eichhornia crassipes (Mart.) Solms. at Camaleão lake, Central Amazonia, Brazil

Abstract

This research describes the influence of biotic and abiotic characteristics on fish fauna structure that inhabits the stands of aquatic macrophytes Eichhornia azurea and Eichhornia crassipes. 182 individuals were sampled belonging to 27 fish species in Camaleão lake, Central Amazonia. Values of dissolved oxygen and water temperature varied from 2.11 to 4.02mgL-1 and 29.17 to 30.93°C for the stands of E. crassipes, and from 1.29 to 2.59mgL-1 and 28.32 and 29.95°C for E. azurea. The highest number of fish species (24), individuals (134), biomass of roots (1572gm-2) belonged to E. azurea. Significantly differences among the stands were obtained to emerged portions (p<0.018; F=8.891) and to the number of individuals that do not support hypoxia (p<0.035; F=6.383). Diversity, evenness and similarity indexes show that fish assemblages associated to banks of E. azurea and E. crassipes have different structure and select the Eichhornia spp stand.