Details

Autor(en) / Beteiligte

• Harris, E
• Diaz-Pines, E
• Stoll, E
• Schloter, M
• Schulz, S
• Duffner, C
• Li, K
• Moore, K L
• Ingrisch, J
• Reinthaler, D
• Zechmeister-Boltenstern, S
• Glatzel, S
• Brüggemann, N
• Bahn, M

Titel

Denitrifying pathways dominate nitrous oxide emissions from managed grassland during drought and rewetting

Ist Teil von

• Science advances, 2021-02, Vol.7 (6)

Ort / Verlag

United States: American Association for the Advancement of Science

Erscheinungsjahr

2021

Quelle

EZB Free E-Journals

Beschreibungen/Notizen

• Nitrous oxide is a powerful greenhouse gas whose atmospheric growth rate has accelerated over the past decade. Most anthropogenic N O emissions result from soil N fertilization, which is converted to N O via oxic nitrification and anoxic denitrification pathways. Drought-affected soils are expected to be well oxygenated; however, using high-resolution isotopic measurements, we found that denitrifying pathways dominated N O emissions during a severe drought applied to managed grassland. This was due to a reversible, drought-induced enrichment in nitrogen-bearing organic matter on soil microaggregates and suggested a strong role for chemo- or codenitrification. Throughout rewetting, denitrification dominated emissions, despite high variability in fluxes. Total N O flux and denitrification contribution were significantly higher during rewetting than for control plots at the same soil moisture range. The observed feedbacks between precipitation changes induced by climate change and N O emission pathways are sufficient to account for the accelerating N O growth rate observed over the past decade.