Journal
GEODERMA
Volume 384, Issue -, Pages -Publisher
ELSEVIER
DOI: 10.1016/j.geoderma.2020.114805
Keywords
Soil-derived organic matter; Adsorption; Goethite; Reactive oxygen species; Fenton reaction
Categories
Funding
- Maine Agricultural and Forest Experiment Station (MAFES) Hatch Project [ME-02163]
- U.S. Department of Energy, Office of Science, Biological and Environmental Research as part of the Terrestrial Ecosystem Sciences Program
- National Science Foundation [DEB-1119709]
- [USDA-NIFA-2018-67019-27801]
Ask authors/readers for more resources
Reactive oxygen species (ROS) oxidized soil organic matter (SOM) through the Fenton reaction, leading to a shift in the adsorption pattern onto mineral surfaces to a more oxidized pool.
Reactive oxygen species (ROS), formed during redox fluctuations in iron-rich soils, have been known to stimulate lignin degradation, although not much is known about how they alter soil organic matter (SOM) composition and interaction with mineral surfaces. We conducted a laboratory experiment to see how ROS altered SOM composition and adsorptive fractionation onto Fe-mineral surfaces. We reacted water extracts of SOM with center dot OH, produced by the Fenton reaction, and then conducted a sorption experiment of the extracts with goethite to analyze the amount and quality of SOM adsorbed. The Fenton reaction preferentially consumed low-O, mostly aromatic molecules, and new high-O molecules were detected post-Fenton, nearly half of which were carbohydrate-like. Although the amount of C adsorbed did not change after oxidation, the post-Fenton adsorbed molecules were more oxidized. Pre-Fenton adsorption was dominated by aromatic molecules (90%), but post-Fenton, the adsorbed molecules were 75% aromatic and 25% carbohydrate-like. We show that the center dot OH radical oxidized SOM and shifted patterns of adsorption to a more oxidized pool. Because adsorption to minerals is thought to stabilize SOM, our results suggest that ROS may alter the availability and stabilization patterns of SOM.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available