Phosphorus Mitigation to Control River Eutrophication: Murky Waters, Inconvenient Truths, and “Postnormal” Science
Top Cited Papers
- 1 March 2013
- journal article
- Published by Wiley in Journal of Environmental Quality
- Vol. 42 (2), 295-304
- https://doi.org/10.2134/jeq2012.0085
Abstract
This commentary examines an "inconvenient truth" that phosphorus (P)-based nutrient mitigation, long regarded as the key tool in eutrophication management, in many cases has not yet yielded the desired reductions in water quality and nuisance algal growth in rivers and their associated downstream ecosystems. We examine why the water quality and aquatic ecology have not recovered, in some case aft er two decades or more of reduced P inputs, including (i) legacies of past land-use management, (ii) decoupling of algal growth responses to river P loading in eutrophically impaired rivers; and (iii) recovery trajectories, which may be nonlinear and characterized by thresholds and alternative stable states. It is possible that baselines have shifted and that some disturbed river environments may never return to predisturbance conditions or may require P reductions below those that originally triggered ecological degradation. We discuss the practical implications of setting P-based nutrient criteria to protect and improve river water quality and ecology, drawing on a case study from the Red River Basin in the United States. We conclude that the challenges facing nutrient management and eutrophication control bear the hallmarks of "postnormal" science, where uncertainties are large, management intervention is urgently required, and decision stakes are high. We argue a case for a more holistic approach to eutrophication management that includes more sophisticated regime-based nutrient criteria and considers other nutrient and pollutant controls and river restoration (e.g., physical habitat and functional food web interactions) to promote more resilient water quality and ecosystem functioning along the land-freshwater continuumKeywords
Funding Information
- Fulbright Scholarship
- OECD Co-operative Research Programme: Biological Resource Management for Sustainable Agricultural Systems
This publication has 113 references indexed in Scilit:
- The Heartbeat of EcosystemsScience, 2012
- Biodiversity loss and its impact on humanityNature, 2012
- Changes in water quality of the River Frome (UK) from 1965 to 2009: Is phosphorus mitigation finally working?Science of The Total Environment, 2011
- Influence of Environmental Factors on Biotic Responses to Nutrient Enrichment in Agricultural Streams1Jawra Journal of the American Water Resources Association, 2010
- The Influence of Nutrients and Physical Habitat in Regulating Algal Biomass in Agricultural StreamsEnvironmental Management, 2010
- Evaluating the Success of Phosphorus Management from Field to WatershedJournal of Environmental Quality, 2009
- Improved water quality in Ohio tributaries to Lake Erie: A consequence of conservation practicesJournal of Soil and Water Conservation, 2009
- Water pollution by agriculturePhilosophical Transactions Of The Royal Society B-Biological Sciences, 2007
- Within-river nutrient processing in Chalk streams: The Pang and Lambourn, UKJournal of Hydrology, 2006
- Nutrient pressures and ecological responses to nutrient loading reductions in Danish streams, lakes and coastal watersJournal of Hydrology, 2005