Unravelling the Contribution of Turbulence and Bubbles to Air-Water Gas Exchange in Running Waters
Aquatic ecosystems exchange gases with the atmosphere and this exchange is critical for many ecosystem processes and the global greenhouse gas cycle. However, it is difficult to determine how fast gases exchange with the atmosphere, especially in running waters where bubbles can speed up the exchange of certain gases. Here, we provide a data set on air-water gas exchange velocities, collected during an outdoor flume experiment. We used experimental stream channels to create a wide range of flow conditions, and tested how these conditions effect the rate at which different gases in the water exchange with the atmosphere. Besides gas exchange velocities for direct air-water exchange and exchange mediated by bubbles, the data set also contains data on, among others, flow conditions, turbulent kinetic energy dissipation rate, bubble flux rate and ambient underwater sound pressure signatures. The experimental design and data are described in articles by Vingiani et al. (2021) and Klaus et al. (2022). main data contributions: (1) Gas exchange velocity estimates based on mass balance of various gases in flume water Concentrations of helium, xenon, argon och methane were measured in the in- and outlet water of the flumes using mass-spectrometry . A mass balance of the gases yielded air-water gas exchange velocities. (2) turbulent kinetic energy dissipation estimates based on Acoustic Doppler Velocimetry Three-dimensional flow velocities were measured at 24 locations per flume using an Acoustic Doppler Velocity meter. Spectral analysis was applied to derives turbulent kinetic energy dissipation rates. (3) sound pressure signatures derived from Hydrophone and microphone recordings Ambient sound was recorded at 12 locations per flume using a hydrophone and a microphone. Spectral analysis was used to derive sound signatures associated with water flow / turbulence and air bubbles.
Vingiani, F., Durighetto, N., Klaus, M., Schelker, J., Labasque, T., & Botter, G. (2021). Evaluating stream CO2 outgassing via drifting and anchored flux chambers in a controlled flume experiment. Biogeosciences, 18, 1223–1240.
Klaus, M., Labasque, T., Botter, G., Durighetto, N., & Schelker, J. (2022). Unraveling the contribution of turbulence and bubbles to air-water gas exchange in running waters. Journal of Geophysical Research: Biogeosciences, 127, e2021JG006520.
Swedish University of Agricultural Sciences
Department of Forest Ecology and Management
Department of Civil Architectural and Environmental Engineering
Department of Functional and Evolutionary Ecology
European Commission's Horizon 2020 Excellent Science Programme
European Commission EU H2020-INFRAIA-project AQUACOSM
Earth and Related Environmental Sciences
Oceanography, Hydrology and Water Resources
Information pertaining to earth sciences.
Inland water features, drainage systems and their characteristics.
A wide inlet of the sea or ocean that is parallel to the coastline; it often separates a coastline from a nearby island.
In hydrology, discharge is the volume rate of water flow that is transported through a given cross-sectional area.(Buchanan, T.J. and Somers, W.P., 1969, Discharge Measurements at Gaging Stations: U.S. Geological Survey Techniques of Water-Resources Investigations, Book 3, Chapter A8, p. 1.) It includes any suspended solids (e.g. sediment), dissolved chemicals (e.g. CaCO3(aq)), or biologic material (e.g. diatoms) in addition to the water itself.
A substance that continues to occupy in a continuous manner the whole of the space in which it is placed, however large or small this place is mad, the temperature remaining constant.
1) A representation, usually on a smaller scale, of a device, structure, etc. \n2) A quantitative or mathematical representation or computer simulation which attempts to describe the characteristics or relationships of physical events.
A natural stream arising in a given drainage basin but not wholly dependent for its flow on surface drainage in its immediate area, flowing in a channel with a well-defined bed between visible banks or through a definite depression in the land, having a definite and permanent or periodic supply of water, and usually, but not necessarily, having a perceptible current in a particular direction and discharging at a fixed point into another body of water.