The removal of riparian vegetation, caused by human activities, has led to a series of changes in streams and may result in ecosystem functions losses. Increasing of structural complexity and trophic diversity of streams, provided by the introduction of wood fragments and leaves, is positively related to the abundance and taxonomic richness of aquatic macroinvertebrates, and cause important changes in functional groups. The main objective of this project is to verify if the trophic structure of aquatic macroinvertebrate is influenced by different types of habitats, by using an experimental approach in which three treatments (with the addition of woody structures; with addition of woody structures and leaves; control) installed in degraded streams will be evaluated. For this, three degraded streams in northwestern state of São Paulo were chosen, in which all needed samplings for the development of the present project were already conducted. At each stream three reaches with 5 m long, uniformly positioned each 20 m were selected for the application of three different treatments: "wood", which received a woody structure of 1m² attached to the substrate; "wood + litter", which received the wood structures with sachets of leaves attached to its bottom surface; and "control", whose channel did not have any change. The macroinvertebrates were sampled at the beginning of the test period, before the installation of the experimental structures, and after six months, at the end of the experiment, using electric fishing equipment and D net sampler. To perform the diet analysis, gut contents of ten individuals of each taxon will be examined in light microscope using a micrometer objective. The determination of trophic guilds in each treatment will be performed by using a cluster analysis with the Bray-Curtis coefficient and to evaluate the influence of wood and leaves in the trophic structure, a similarity analysis (ANOSIM) will be conducted.
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