AN OVERVIEW OF SOME ASPECTS OF RIVER ECOLOGY: A CASE STUDY ON FISH ASSEMBLAGES DISTRIBUTION IN AN EASTERN BRAZILIAN COASTAL RIVER

Abstract

An overview of studies and theories on river ecology is presented, given enphasis to the importance of longitudinal processes in defining the structure and function of river fish communities. Fish communities in 14 sites in Macacu River, RJ, Brazil, were investigated. A pattern of fish structure has been revealed and related to longitudinal changes of environmental data and trophic composition. The increase in fish diversity with river size, associated with the decrease in the variability of abiotic factors, support qualitative prediction of the River Continuum Concept: consistent shifts in community organization associated with spatial changes in channel morphology and resource availability.