Listening to air–water gas exchange in running waters

• DOI: 10.1002/lom3.10321
• Publication Date: 2019-06-12T09:42:18Z
• Authors: Marcus Klaus; Erik Geibrink; Erin R. Hotchkiss; Jan Karlsson
• Keywords: Biogeochemical Cycle

Abstract Air–water gas exchange velocities ( k ) are critical components of many biogeochemical and ecological process studies in aquatic systems. However, their high spatiotemporal variability is difficult to capture with traditional methods, especially turbulent flow. Here, we investigate the potential sound spectral analysis infer running waters, based on rationale that both turbulence entrained bubbles drive cause a characteristic sound. We explored relationship between properties using laboratory experiments field observations under wide range bubble conditions. estimated flux chamber measurements CO 2 recorded above below water surface by microphones hydrophones, respectively. found strong influence pressure levels (SPLs) at octave bands 31.5 Hz 1000 Hz, The difference SPLs these background noise showed linear correlation R = 0.93–0.99) (median 0.42–0.90). Underwater indices outperformed aerial general, hydraulic parameters particular, bubbly results highlight unique acoustic techniques predict , isolate mechanisms, improve coverage estimates