A heterogeneidade de bancos de macrófitas aquáticas e a diversidade de peixes em uma ria fluvial amazônica

Abstract

In freshwater ecosystems, macrophyte species can provide habitat heterogeneity with different structural forms, ranging from free submerged species to rooted species, which serve as a substrate for spawning, food and refuge against predation to fish and other organism. In the 49 present work we tested the effect of the heterogeneity of aquatic macrophyte banks on the richness and abundance and functional traits of the fish in flooded rivers of the Amazon. To investigate the relationship between the heterogeneity of the macrophyte banks and the richness, abundance, and functional characteristics of the fish, we used them CWM analysis and simple linear regressions. We identified 16 species of aquatic macrophytes and 21 species of fish in the 34 sampling points. The macrophyte banks were dominated by the species Eichhornia azurea and. E. crassipes. The most abundant fish species were Hemigrammus ocellifer and Laimosemion strigatus. The linear regression result was only significant between the heterogeneity of the macrophyte banks on two functional attributes, both linked to the locomotion of the fish. Our results show that the association between the heterogeneity provided by the macrophyte banks is an environmental filter for fish species that have high maneuverability, since these species can swim between macrophyte structures. Thus, we can observe that the heterogeneity provided by aquatic macrophytes, although not affecting the richness and abundance of fish, is important for different species of fish, but for those that use and depend on these banks as a refuge.