Effects of urbanization on streams of the Melbourne region, Victoria, Australia. I. Benthic macroinvertebrate communities

Abstract

1. Macroinvertebrate community composition was assessed in small streams of the Melbourne region to test the effects of (a) urban density (catchment imperviousness 0-51%) and (b) stormwater drainage intensity (comparing the intensively drained metropolitan area with urban areas of the hinterland, which had open drains and some localized stormwater drainage). 2. Hinterland communities separated into two groups of sites correlating strongly with patterns of electrical conductivity (EC), basalt geology and annual rainfall. Community composition varied little in the high-EC, western group (imperviousness 0.2-1.2%), but in the eastern group it was strongly correlated with catchment imperviousness..