The concept of environmental flows has been developed to manage human alteration of river flow regimes, as effective management requires an understanding of the ecological consequences of flow alteration. This study explores the concept of macroinvertebrate sensitivity to river flow alteration to establish robust quantitative relationships between biological indicators and hydrological pressures. Existing environmental flow classifications used by the environmental regulator for English rivers were tested using multilevel regression modelling. Results showed a weak relationship between the current abstraction sensitivity classification and macroinvertebrate response to flow pressure. An alternative approach, based on physically derived river types, was a better predictor of macroinvertebrate response. Intermediate sized lowland streams displayed the best model fit, while upland rivers exhibited poor model performance. A better understanding of the ecological response to flow variation in different river types could help water resource managers develop improved ecologically appropriate flow regimes, which support the integrity of river ecosystems.
Bibliographical noteFunding Information:
The views expressed in this paper reflect those of the authors and are not necessarily indicative of the position held by the Environment Agency. The authors thank numerous colleagues in the Environment Agency who have contributed to the data collection, collation and advice on the analysis and early drafts of the manuscript, especially Sarah Peet, Judith Bennett, Mark Warren and Alison Futter. This project was jointly funded by a research grant awarded to the University of Birmingham by the Environment Agency and the Irish Environmental Protection Agency, Office of Evidence and Assessment.
- abstraction sensitivity
- flow–ecology relationships
- LIFE index
- mixed effects modelling
ASJC Scopus subject areas
- Environmental Engineering
- Water Science and Technology
- Management, Monitoring, Policy and Law