Trophic organization and food web structure of southeastern Brazilian streams: a review.

UIEDA¹, V. S. & MOTTA¹, R. L.

¹ Departamento de Zoologia, Instituto de Biociências, C.P. 510, Universidade Estadual Paulista-UNESP, 18618-000, Botucatu, SP, Brasil.

vsuieda@ibb.unesp.br motta_rl@ig.com.br

ABSTRACT: The present study reviews some trophic patterns of southeastern Brazilian streams. The food resources availability, the relationship between production and importation, the establishment of feeding guilds, and the patterns of trophic structure of fish and macroinvertebrate communities, with a particular emphasis on food webs, are discussed. In the four food webs used as examples, the following aspects were emphasized: (1) the importance of allochthonous material input to the aquatic system, (2) the importance of detritus and algae as a link between the detritus and the grazing chain, (3) the spatial and temporal variation in the trophic structure, and (4) the high degree of omnivory.

Key-words: trophic structure, stream, macroinvertebrates, fish, food web.