Global soil nitrous oxide emissions since the pre-industrial era estimated by an ensemble of Terrestrial Biosphere Models: Magnitude, attribution and uncertainty

Tian H, Yang J, Xu R, Lu C, Canadell JG, Davidson EA, Jackson RB, Arneth A, et al. (2018). Global soil nitrous oxide emissions since the pre-industrial era estimated by an ensemble of Terrestrial Biosphere Models: Magnitude, attribution and uncertainty. Global Change Biology DOI:10.1111/gcb.14514. (In Press)

[img] Text
Tian_et_al-2018-Global_Change_Biology.pdf - Accepted Version
Restricted to Repository staff only until 10 November 2019.
Available under License Creative Commons Attribution Non-commercial.

Download (1MB)

Abstract

Our understanding and quantification of global soil nitrous oxide (N2 O) emissions and the underlying processes remain largely uncertain. Here we assessed the effects of multiple anthropogenic and natural factors, including nitrogen fertilizer (N) application, atmospheric N deposition, manure N application, land cover change, climate change and rising atmospheric CO2 concentration, on global soil N2 O emissions for the period 1861-2016 using a standard simulation protocol with seven process-based terrestrial biosphere models. Results suggest global soil N2 O emissions have increased from 6.3 ± 1.1 Tg N2 O-N yr-1 in the pre-industrial period (the 1860s) to 10.0 ± 2.0 Tg N2 O-N yr-1 in the recent decade (2007-2016). Cropland soil emissions increased from 0.3 Tg N2 O-N yr-1 to 3.3 Tg N2 O-N yr-1 over the same period, accounting for 82% of the total increase. Regionally, China, South Asia and Southeast Asia underwent rapid increases in cropland N2 O emissions since the 1970s. However, US cropland N2 O emissions had been relatively flat in magnitude since the 1980s, and EU cropland N2 O emissions appear to have decreased by 14%. Soil N2 O emissions from predominantly natural ecosystems accounted for 67% of the global soil emissions in the recent decade but showed only a relatively small increase of 0.7 ± 0.5 Tg N2 O-N yr-1 (11%) since the 1860s. In the recent decade, N fertilizer application, N deposition, manure N application and climate change contributed 54%, 26%, 15% and 24%, respectively, to the total increase. Rising atmospheric CO2 concentration reduced soil N2 O emissions by 10% through the enhanced plant N uptake, while land cover change played a minor role. Our estimation here does not account for indirect emissions from soils and the directed emissions from excreta of grazing livestock. To address uncertainties in estimating regional and global soil N2 O emissions, this study recommends several critical strategies for improving the process-based simulations.

Item Type: Article
Uncontrolled Keywords: Global nitrogen cycle; Greenhouse gas emission; Nitrous oxide; Process-based modeling; Soil N2O emission
Research Programs: Air Quality & Greenhouse Gases (AIR)
Depositing User: Luke Kirwan
Date Deposited: 12 Nov 2018 07:38
Last Modified: 12 Nov 2018 07:38
URI: http://pure.iiasa.ac.at/15570

Actions (login required)

View Item View Item

International Institute for Applied Systems Analysis (IIASA)
Schlossplatz 1, A-2361 Laxenburg, Austria
Phone: (+43 2236) 807 0 Fax:(+43 2236) 71 313