Incorporation of zinc and copper by insects of different functional feeding groups in agricultural streams

Abstract

Metals from agricultural areas are responsible for soil contamination and are carried into aquatic ecosystems. In this context, we evaluated the incorporation of zinc and copper via three feeding strategies (shredding, herbivory and predators) in assemblages of stream insects. We collected aquatic insects in five agricultural streams and five natural streams in Atlantic forest biome to investigate the accumulation of copper and zinc in insects with different feeding strategies. We found no significant differences in the concentrations of copper and zinc between stream types among all insect-feeding groups compared. However, we observed that copper accumulate concentrations differed significantly among the shredders and predators in relation to their resource in streams, while zinc concentrations differed in the two feeding strategy. Therefore, the investigation of the transfer of copper and zinc by different feeding strategies in streams can contribute to the understanding of changes in aquatic insect assemblages related to agricultural activities around streams.

Keywords: Bioaccumulation; Feeding strategy; Herbivores; Predators; Scrapers; Shredders.