A dramatic change in the way oxygen is produced and used in inland waterways is ‘suffocating” lakes and rivers, new research has concluded.
The research, led by Utrecht University in the Netherlands, was published this week in Science Advances.
It found that human activity since 1900 had altered the ability of inland waterways to “breathe” oxygen.
“Oxygen, the most critical resource for life on Earth, plays an important role in other nutrient cycles such as carbon and nitrogen,” the research report said.
“Oxygen depletion in water, called hypoxia, is causing problems. They are piling up in various coastal and freshwater systems. This study shows it’s not just a local problem -it’s a planetary one.”
The report said that the suffocation was leading to poor water quality, dying fish and disrupted food webs.
This impact on rivers, streams, lakes, and reservoirs was a concern because they were “vital engines” for life on Earth.
Researcher Jack Middelburg said it was hoped that by developing a complex understanding of oxygen on a large scale, problems could be predicted and mitigated.
He said inland waters had become “busier” places with greater “oxygen turnover”.
The increased oxygen turnover is due to increased farming, wastewater, dams, and a warmer climate.
“But here’s the twist: these waters are consuming more oxygen than they produce, making them a growing sink of atmospheric oxygen,” Professor Middelburg said.
“Even though these waters cover just a tiny fraction of Earth’s surface, they now remove nearly one billion tonnes of oxygen from the atmosphere each year—overall half of what the entire ocean emits back.”
The full report is on the University of Utrecht website.
