Academics from the University of Essex are among an international research team which has linked glacier-fed mountain rivers with the release of carbon dioxide into the air.
As mountain glaciers melt, water is channelled into rivers downstream. But with global warming accelerating the loss of glaciers, rivers have warmer water temperatures and provide a better habitat for fungi to establish and grow.
The fungi decompose organic matter, such as plant leaves and wood, eventually leading to the release of carbon dioxide into the air. The process has now been measured in 57 rivers in six mountain ranges in Austria, Ecuador, France, New Zealand, Norway and the United States.
The researchers say the retreat of mountain glaciers is accelerating at an unprecedented rate in many parts of the world, with climate change predicted to drive continued ice loss throughout the 21st century.