Dynamics ofnitrate production and removal as a function of residence time in the hyporheiczone: a 15N tracer studyJournal of Geophysical Research - Biogeosciences (2011)
AbstractBiogeochemical reactions associated with stream nitrogen cycling, such as nitrification and denitrification, can be strongly controlled by water and solute residence times in the hyporheic zone (HZ). We used a whole-stream steady state 15N-labeled nitrate (15NO3−) and conservative tracer (Cl−) addition to investigate the spatial and temporal physiochemical conditions controlling the denitrification dynamics in the HZ of an upland agricultural stream. We measured solute concentrations (15NO3−, 15N2 (g), as well as NO3−, NH3, DOC, DO, Cl−), and hydraulic transport parameters (head, flow rates, flow paths, and residence time distributions) of the reach and along HZ flow paths of an instrumented gravel bar. HZ exchange was observed across the entire gravel bar (i.e., in all wells) with flow path lengths up to 4.2 m and corresponding median residence times greater than 28.5 h...
- hyporheic zone
Citation InformationZarnetske, J.P.*, R.D. Haggerty, S.M. Wondzell, and M.A. Baker. 2011. Dynamics of nitrate production and removal as a function of residence time in the hyporheic zone: a 15N tracer study. Journal of Geophysical Research- Biogeosciences. 116, G01025doi:10.1029/2010JG001356.