Title:	Contrasting land uses affect Chironomidae communities in two Brazilian rivers.
Authors:	SONODA, K. C. MATTHAEI, C. D. TRIVINHO-STRIXINO, S.
Affiliation:	KATHIA CRISTHINA SONODA, CPAC; CHRISTOPH D. MATTHEI, UNIVERSITY OF OTAGO; SUSANA TRIVINHO-STRIXINO, UNIVERSIDADE FEDERAL DE SÃO CARLOS.
Date Issued:	2009
Citation:	Archiv für Hydrobiologie, Fundamental and Applied Limnology, v. 174, n. 2, p. 173-184, 2009.
Description:	ABSTRACT: We investigated whether the conversion of riparian land use from indigenous forest to pasture influences Chironomidae (midge) community in two Brazilian rivers. Our study was conducted in the main rivers (São José do Dourados 6th order, Aguapéi 7th order) of two large catchments in the State of São Paulo. Both are dominated by agricultural ecosystems but retain substancial patches of native riparian forest. Replicated artificial substrates (baskets filled with coarse clay gravel) were exposed at one forested reach and one pasture reach in each river. Each respective land use had to be present for at least 500m along both river banks above and alongside the study reach, and the riparian forest at the forested reaches had to be at least 50m wide. Colonisation baskets were sampled after 44 days and all midge larvae sorted and identified to the lowest level possible (a total of 5,286 individuals belonging to 27 taxa). Land use affected midge communities, but not as expected. Densities of three dominant midge genera were significantly higher in pasture reaches than in forested reaches, possibly in response to moderate nutrient enrichment at the pasture reaches. Total density and taxon richness were similar across land uses. These results imply that land-use related changes in habitat conditions were not severe enough to represent a stressor (with negative effects) for the midge communities in the investigated large rivers, but rather acted as a subsidy, with mainly positive effects.
Thesagro:	Díptera Rio Uso da Terra
NAL Thesaurus:	Chironomidae
Keywords:	Inseto aquático
Type of Material:	Artigo de periódico
Access:	openAccess
Appears in Collections:	Artigo em periódico indexado (CPAC)