N 2 O emissions from decomposing crop residues are strongly linked to their initial soluble fraction and early C mineralization.

Autor: Lashermes G; Université de Reims Champagne Ardenne, INRAE, FARE, UMR A 614, 51097 Reims, France. Electronic address: gwenaelle.lashermes@inrae.fr., Recous S; Université de Reims Champagne Ardenne, INRAE, FARE, UMR A 614, 51097 Reims, France., Alavoine G; Université de Reims Champagne Ardenne, INRAE, FARE, UMR A 614, 51097 Reims, France., Janz B; Karlsruhe Institute of Technology, Institute of Meteorology and Climate Research-Atmospheric Environmental Research, Garmisch-Partenkirchen, Germany., Butterbach-Bahl K; Karlsruhe Institute of Technology, Institute of Meteorology and Climate Research-Atmospheric Environmental Research, Garmisch-Partenkirchen, Germany., Ernfors M; Swedish University of Agricultural Sciences, Department of Biosystems and Technology, P.O. Box 103, SE-230 53 Alnarp, Sweden., Laville P; Paris-Saclay, INRAE, AgroParisTech, UMR ECOSYS, 78850 Thiverval-Grignon, France.
Jazyk: angličtina
Zdroj: The Science of the total environment [Sci Total Environ] 2022 Feb 01; Vol. 806 (Pt 4), pp. 150883. Date of Electronic Publication: 2021 Oct 12.
DOI: 10.1016/j.scitotenv.2021.150883
Abstrakt: The emission of nitrous oxide (N 2 O), a strong greenhouse gas, during crop residue decomposition in the soil can offset the benefits of residue recycling. The IPCC inventory considers agricultural N 2 O emissions proportional to the amount of nitrogen (N) added by residues to soils. However, N 2 O involves several emission pathways driven directly by the form of N returned and indirectly by changes in the soil induced by decomposition. We investigated the decomposition factors related to N 2 O emissions under controlled conditions. Residues of sugar beet (SUB), wheat (WHT), rape seed (RAS), potato (POT), pea (PEA), mustard (MUS), red clover (RC), alfalfa (ALF), and miscanthus (MIS), varying by maturity at the time of collection, were incubated in two soils (GRI and SLU) at 15 °C with a water-filled pore space of 60%. The residues contained a wide proportion range of water-soluble components, components soluble in neutral detergent (SOL-NDS), hemicellulose, cellulose, and lignin. Their composition drastically influenced the dynamics of C mineralization and soil ammonium and nitrate and was correlated with N 2 O flux dynamics. The net cumulative N 2 O emitted after 60 days originated mostly from MUS (4828 ± 892 g N-N 2 O ha -1 ), SUB (2818 ± 314 g N-N 2 O ha -1 ) and RC (2567 ± 1245 g N-N 2 O ha -1 ); the other residue treatments had much lower emissions (<200 g N-N 2 O ha -1 ). For the first time N 2 O emissions could be explained only by the residue content in the SOL-NDS, according to an exponential relationship. Residues with a high SOL-NDS (>25% DM) were also non-senescent and promoted high N 2 O emissions (representing 1-5% of applied N), likely directly by nitrification and indirectly by denitrification in microbial hotspots. Crop residue quality appears to be valuable information for accurately predicting N 2 O emissions and objectively weighing their other potential benefits to agriculture and the environment.
Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
(Copyright © 2021 Elsevier B.V. All rights reserved.)
Databáze: MEDLINE
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