Effect of Dissolved Oxygen on Redox Potential and Nitrate Removal in Flooded Swamp and Marsh Soils1
- R. M. Engler,
- D. A. Antie and
- W. H. Patrick2
The O2 depletion rates, NO3− loss, and the effects of added O2 on NO3− disappearance and redox potential in four flooded or intermittently flooded soils from the swamp and coastal marshes of Louisiana were quantitatively characterized in a laboratory study. The NO3− added either to the shallow floodwater or mixed with the soil in a suspension rapidly disappeared. Eighty to ninety parts per million NO3− was lost from the soil suspensions in 1 to 4 days and from the floodwater over a soil in 10 to 20 days. No NO3− was lost from floodwater separated from the soils. Oxygen depletion in the soil suspensions occurred in 15 minutes to 4 hours. Redox potential curves exhibited a characteristic inflection after O2 disappearance in all soils studied. Nitrate disappearance did not appear to be inhibited by as much as 16 ppm O2 dissolved in the soil suspensions because the O2 was rapidly consumed.Please view the pdf by using the Full Text (PDF) link under 'View' to the left.
Copyright © . .