ESTRUCTURA DE MACROINVERTEBRADOS ACUÁTICOS EN UN RÍO ALTOANDINO DE LA CORDILLERA REAL, BOLIVIA: VARIACIÓN ANUAL Y LONGITUDINAL EN RELACIÓN A FACTORES AMBIENTALES

Abstract

In this work the available information from scientifi c and technical studies is compiled and analyzed, to determine the taxonomic composition and trophic structure of river communities belonging to fi ve hydrological basins of Chile, located within an arid-Mediterranean environmental gradient. The basins were: Loa, Huasco, Limarí, Cachapoal y Mataquito. The four most important taxonomic groups were considered: fi sh, benthic macroinvertebrates, macrofi tes and benthic diatoms. The taxonomic and trophic structures of 10 communities from the studied basins were determined. The analyses indicated that: (a) each basin shows a characteristic taxonomic structure; (b) no patterns were found of increase or decrease in diversity along the arid-Mediterranean gradient, only fi nding a pattern along the upstream-downstream gradient within a system; (c) benthic macroinvertebrates shows a taxonomic particular and differentiable composition for the zones arid, semiarid and Mediterranean; (d) the taxonomic composition of each group was found to be signifi cantly nested between rivers, and (e) fi ve types of food webs were identifi ed for the total of studied community systems, represented by functional groups and their feeding relationships. Future research should be oriented towards increasing the taxonomic resolution of the food webs and incorporate other relevant functional features.