The gas exchange through the turbulent surface of mountain streams is critical to numerous ecosystem processes. It regulates ecosystem metabolism and vents climate-relevant gases from the streamwater into the atmosphere. Most of our current understanding on gas exchange in streams rests on streams with low channel slopes and often swiftly flowing water; it is therefore not well suited for mountain streams with steep channel slopes and elevated turbulence. We are using argon injections in our mountain streams to determine gas exchange velocity, which we then relate to predictors informing on the turbulence in these streams. Our work on this topic is relevant for several projects at SBER, including those on ecosystem metabolism and CO2 evasion fluxes.
EPFL Scientist: Lluis Gómez Gener, Amber Ulseth (now at Sam Houston State University, USA); Research Technician: Nicola Deluigi; MSc student: Kate Schuler