The ecology of rivers with contrasting flow regimes: identifying indicators for setting environmental flows

摘要: The scientific basis for setting environmental flows is still hampered by our incomplete understanding of flow–ecology relationships and how river ecology varies with flow regime. We conducted a study six rivers in Tasmania (Australia), three perennial intermittent, measuring range abiotic, biotic ecosystem process attributes over 2 years. Our intentions were to identify: (i) whether they had an characteristic their regime (ii) certain ecological more responsive than others, therefore represented candidate indicators (for or alteration) specific each Only few abiotic variables showed any relationship regime: banks higher, pools shallower sediments finer rivers, water temperature was generally lower rivers. Although rarely measured, we found that productivity net metabolism strongly related regime, whereas food chain length did not vary between intermittent Multivariate, rather univariate, metrics assemblages effective at distinguishing regimes, this consistent among riparian instream vegetation, biofilm macroinvertebrate assemblages. In contrast expectations from the literature, fish strong largely due relatively low diversity abundance Tasmanian fauna. findings demonstrate different regimes can support distinctive ecology, conventional character may be most sensitive provide set can: extrapolation across regional scales, benchmarks restoration objectives, (iii) indicate alterations natural existing (iv) used monitor evaluate management actions.