| Summary: | Benthic macroinvertebrates were collected from streams located in an urban area from regions featuring different environmental conditions. Physicochemical variables and land use types pertaining to sampling sites were analyzed concurrently. Multivariate analyses (cluster analysis and non-metric multidimensional scaling) and rank-abundance diagrams were used to characterize community patterns to assess ecological integrity in response to environmental conditions. Species composition patterns were mainly influenced by both the gradient of physicochemical variables (e.g., altitude, slope, conductivity) and the proportion of forest area. Community structure patterns were further correlated to the proportion of urbanization and to biological indices (e.g., diversity, number of species). Land use preferences of benthic species were identified based on the indicator values and weighted averaging regression models. Plecoptera species were representative of undisturbed streams in forest areas, whereas Tubificidae species and filtering collector caddis flies were indicator taxa in severely polluted and agricultural areas, respectively. The analyses of community structures and indicator species effectively characterized community properties and ecological integrity following natural and anthropogenic variability in urban stream ecosystems.
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