A new study has warned that climate change could fuel a rise in algal blooms in the River Thames, even though phosphorus levels an essential nutrient for algae have significantly decreased over the past four decades.
Led by Helen Jarvie, a professor at the University of Waterloo, the research found that phosphorus loads in the Thames have dropped by 80% due to improved wastewater treatment and agricultural practices. Despite this progress, rising river temperatures driven by climate change are increasing the risk of both spring diatom blooms and summer cyanobacterial blooms. These algal blooms can harm aquatic ecosystems by suffocating marine life, depleting oxygen levels, and releasing potentially toxic cyanobacteria.
Water Quality Management at Risk
Jarvie emphasized that while phosphorus reduction has been a major success, climate change is undermining these efforts by creating conditions more favorable for algal growth. The blooms not only threaten biodiversity but also raise drinking water treatment costs and restrict recreational activities like swimming, fishing, and sailing.
Her research, which spans 150 years of river water quality data, highlights the urgent need for adaptive water management strategies in a warming climate. The study, titled A 150-year river water quality record shows reductions in phosphorus loads but not in algal growth potential, was published in Communications Earth & Environment.