Effects of urbanization on stream benthic invertebrate communitiesin Central Amazon
Carregando...
Data
2017
Título da Revista
ISSN da Revista
Título de Volume
Editor
Resumo
Urbanization and its physical and chemical effects on aquatic environments influence invertebrate com-munities negatively. Yet, it is not clear how urbanization affects inter-annual variation of invertebrateassemblages in streams. We 1) evaluated urbanization effects on the ecological conditions (biotic and abi-otic) of streams in Manaus and 2) analyzed invertebrate community variation over time (between 2003and 2010). Data on abiotic variables and invertebrates from 2003 were obtained from a previous study. In2010 we sampled abiotic variables and invertebrate communities in the same low-order urban streamssampled in 2003 (n = 40). We recorded high values of total nitrogen, total phosphorous, deforestation,total impervious area (TIA), water temperature, pH, and electrical conductivity in the most urbanizedstreams, as compared to the least-impacted ones. In contrast, the least-impacted streams had high dis-solved oxygen concentrations. Water quality was poorer in 2010 than in 2003: oxygen concentrationwas lower and total nitrogen, total phosphorous, deforestation, and TIA significantly higher in 2010. Werecorded higher inter-annual variation of abiotic variables in the most-impacted streams as compared tothe least-impacted streams. EPT (%, Ephemeroptera, Plecoptera, and Trichoptera) and richness metricsdecreased with urbanization. On the other hand, % OP (percent of Oligochaeta and Psychodidae) increasedwith urbanization. Observed and EPT richness and% OP increased between 2003 and 2010. On the otherhand, rarefied richness decreased between years. Increases of observed and EPT richness between 2003and 2010 were related to low inter-annual variability in streams conditions; however, differences of% OPand rarefied richness were not related to inter-annual variability in environmental conditions. The degreeof urbanization did not explain the magnitude of the within-stream difference of invertebrate commu-nities between 2003 and 2010. The increased effects of urbanization represented by the abiotic variablessampled and the reduction of invertebrate richness and increased dominance of tolerant taxa indicatethat public policy is not enough to protect or mitigate human impacts on the urban water systems understudy.
Descrição
Palavras-chave
Abiotic variables, Aquatic insects, Inter annual variation, Urbanization
Citação
MARTINS, Renato T.; COUCEIRO, Sheyla R. M.; MELO, Adriano S.; MOREIRA, Marcelo P.; HAMADA, Neusa. Effects of urbanization on stream benthic invertebrate communities in Central Amazon. Ecological Indicators, London, v. 73, p. 480-491, 2017.