Quin, P R; Joseph, Stephen; Husson, O; Donne, S; Mitchell, D; Munroe, P; Phelan, D; Cowie, Annette; Van Zwieten, L

Author(s)

Quin, P R

Joseph, Stephen

Husson, O

Donne, S

Mitchell, D

Munroe, P

Phelan, D

Cowie, Annette

Van Zwieten, L

Publication Date

2015

Abstract

Agricultural soils are the primary anthropogenic source of atmospheric nitrous oxide (N₂O), contributing to global warming and depletion of stratospheric ozone. Biochar addition has shown potential to lower soil N₂O emission, with the mechanisms remaining unclear. We incubated eucalypt biochar (550°C) - 0, 1 and 5% (w/w) in Ferralsol at 3 water regimes (12, 39 and 54% WFPS) - in a soil column, following gamma irradiation. After N₂O was injected at the base of the soil column, in the 0% biochar control 100% of expected injected N₂O was released into headspace, declining to 67% in the 5% amendment. In a 100% biochar column at 6% WFPS, only 16% of the expected N₂O was observed. X-ray photoelectron spectroscopy identified changes in surface functional groups suggesting interactions between N₂O and the biochar surfaces. We have shown increases in -O-C = N /pyridine pyrrole/NH₃, suggesting reactions between N₂O and the carbon (C) matrix upon exposure to N₂O. With increasing rates of biochar application, higher pH adjusted redox potentials were observed at the lower water contents. Evidence suggests that biochar has taken part in redox reactions reducing N₂O to dinitrogen (N₂), in addition to adsorption of N₂O.

Citation

Scientific Reports, v.5, p. 1-14

ISSN

2045-2322

Link

https://hdl.handle.net/1959.11/21414

Publisher

Nature Publishing Group

Title

Lowering N2O emissions from soils using eucalypt biochar: the importance of redox reactions

Type of document

Journal Article

Entity Type

Publication

Author(s)	Quin, P R Joseph, Stephen Husson, O Donne, S Mitchell, D Munroe, P Phelan, D Cowie, Annette Van Zwieten, L
Publication Date	2015
Abstract	Agricultural soils are the primary anthropogenic source of atmospheric nitrous oxide (N₂O), contributing to global warming and depletion of stratospheric ozone. Biochar addition has shown potential to lower soil N₂O emission, with the mechanisms remaining unclear. We incubated eucalypt biochar (550°C) - 0, 1 and 5% (w/w) in Ferralsol at 3 water regimes (12, 39 and 54% WFPS) - in a soil column, following gamma irradiation. After N₂O was injected at the base of the soil column, in the 0% biochar control 100% of expected injected N₂O was released into headspace, declining to 67% in the 5% amendment. In a 100% biochar column at 6% WFPS, only 16% of the expected N₂O was observed. X-ray photoelectron spectroscopy identified changes in surface functional groups suggesting interactions between N₂O and the biochar surfaces. We have shown increases in -O-C = N /pyridine pyrrole/NH₃, suggesting reactions between N₂O and the carbon (C) matrix upon exposure to N₂O. With increasing rates of biochar application, higher pH adjusted redox potentials were observed at the lower water contents. Evidence suggests that biochar has taken part in redox reactions reducing N₂O to dinitrogen (N₂), in addition to adsorption of N₂O.
Citation	Scientific Reports, v.5, p. 1-14
ISSN	2045-2322
Link	https://hdl.handle.net/1959.11/21414
Publisher	Nature Publishing Group
Title	Lowering N2O emissions from soils using eucalypt biochar: the importance of redox reactions
Type of document	Journal Article
Entity Type	Publication

Lowering N2O emissions from soils using eucalypt biochar: the importance of redox reactions

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