For the first time, an EPFL-led team of scientists has measured the total amount of CO2 emissions from mountain streams worldwide.
For the first time, an EPFL-led team of scientists has measured the total amount of CO2 emissions from mountain streams worldwide. This research builds on findings issued in February 2019 and shows how important it is to include mountain streams in assessments of the global carbon cycle.
Mountains cover 25% of the Earth's surface, and the streams draining these mountains account for more than a third of the global runoff. But the role that mountain streams play in global carbon fluxes has not yet been evaluated; until now scientists have focused mainly on streams and rivers in low-altitude tropical and boreal regions.
Åsa Horgby, a PhD student at EPFL's Stream Biofilm and Ecosystem Research Laboratory (SBER), along with a team of international scientists has performed the first large-scale study of the CO2 emissions of mountain streams and their role in global carbon fluxes. They found that these streams have a higher average CO2 emission rate per square meter than streams at lower altitudes, due in part to the additional turbulence caused as water flows down mountain slopes. So even though these streams make up just 5% of the global surface area of the fluvial networks, they likely account for 10% to 30% of CO2 emissions from these networks. The scientists' findings were published today in Nature Communications.
Read more at Ecole Polytechnique Fédérale de Lausanne
Image: This is an overview of the Alps. (Credit: NASA.GOV)
