Nitrogen-rich organic soils under warm well-drained conditions are global nitrous oxide emission hotspots

Jaan Parn (1, 2) , Jos T A Verhoeven (3) , Klaus Butterbach-Bahl (4) , Nancy B Dise (5) , Sami Ullah (2) , Anto Aasa (1) , Sergey Egorov (1) , Mikk Espenberg (1) , Järvi Järveoja (1) , Jyrki Jauhiainen (6) , Kuno Kasak (1) , Leif Klemedtsson (7) , Ain Kull (1) , Fatima Laggoun-Défarge (8, 9) , Elena D Lapshina (10) , Annalea Lohila (11) , Krista Lõhmus (12) , Martin Maddison (1) , William J Mitsch , Christoph Müller , Ülo Niinemets (13) , Bruce Osborne (14) , Taavi Pae (1) , Jüri-Ott Salm (15) , Fotis Sgouridis (16) , Kristina Sohar (1) , Kaido Soosaar (1) , Kathryn Storey (17) , Alar Teemusk (1) , Moses M Tenywa (18) , Julien Tournebize (19) , Jaak Truu (1) , Gert Veber (1) , Jorge A Villa (20) , Seint Sann Zaw (21) , Ülo Mander (1)

1 Department of Geography, Tartu
2 School of Geography, Geology and the Environment
3 Ecology and Biodiversity, Departement of Biology
4 Institute of Meteoroly and Climate Research
5 CEH - Centre for Ecology and Hydrology [Edinburgh]
6 LUKE - Natural Resources Institute Finland
7 Department of Earth Sciences [Gothenburg]
8 ISTO - Institut des Sciences de la Terre d'Orléans - UMR7327
9 Biogéosystèmes Continentaux - UMR7327
10 UNESCO Chair of Environnemental Dynamics and Climate Change
11 Atmospheric Composition Research [Helsinki]
12 Department of Botany [Tartu]
13 EMU - Estonian University of Life Sciences
14 UCD - University College Dublin [Dublin]
15 Estonian Fund for Nature
16 School of Geographical Sciences [Bristol]
17 Department of Primary Industries, Parks, Water and Environment
18 Department of Agricultural Production, College of Agricultural and Environmental Sciences
19 UR HYCAR - Hydrosystèmes continentaux anthropisés : ressources, risques, restauration
20 Grupo de Investigación Aplicada al Medio Ambiente
21 Forest Resource Environment Development and Conservation Association

Nitrous oxide (N 2 O) is a powerful greenhouse gas and the main driver of stratospheric ozone depletion. Since soils are the largest source of N 2 O, predicting soil response to changes in climate or land use is central to understanding and managing N 2 O. Here we find that N 2 O flux can be predicted by models incorporating soil nitrate concentration (NO 3 −), water content and temperature using a global field survey of N 2 O emissions and potential driving factors across a wide range of organic soils. N 2 O emissions increase with NO 3 − and follow a bell-shaped distribution with water content. Combining the two functions explains 72% of N 2 O emission from all organic soils. Above 5 mg NO 3 −-N kg −1 , either draining wet soils or irrigating well-drained soils increases N 2 O emission by orders of magnitude. As soil temperature together with NO 3 − explains 69% of N 2 O emission, tropical wetlands should be a priority for N 2 O management.

Domaines: Planète et Univers [physics]; Interfaces continentales, environnement

Jaan Parn, Jos T A Verhoeven, Klaus Butterbach-Bahl, Nancy B Dise, Sami Ullah, et al.. Nitrogen-rich organic soils under warm well-drained conditions are global nitrous oxide emission hotspots. Nature Communications, 2018, 9 (1), 8 p. ⟨10.1038/s41467-018-03540-1⟩. ⟨insu-01759495⟩