Details

Autor(en) / Beteiligte

• Zhou, Minghua
• Zhu, Bo
• Wang, Shijie
• Zhu, Xinyu
• Vereecken, Harry
• Brüggemann, Nicolas

Titel

Stimulation of N2O emission by manure application to agricultural soils may largely offset carbon benefits: a global meta‐analysis

Ist Teil von

• Global change biology, 2017-10, Vol.23 (10), p.4068-4083

Ort / Verlag

Oxford: Blackwell Publishing Ltd

Erscheinungsjahr

2017

Link zum Volltext

Quelle

Wiley Online Library

Beschreibungen/Notizen

• Animal manure application as organic fertilizer does not only sustain agricultural productivity and increase soil organic carbon (SOC) stocks, but also affects soil nitrogen cycling and nitrous oxide (N2O) emissions. However, given that the sign and magnitude of manure effects on soil N2O emissions is uncertain, the net climatic impact of manure application in arable land is unknown. Here, we performed a global meta‐analysis using field experimental data published in peer‐reviewed journals prior to December 2015. In this meta‐analysis, we quantified the responses of N2O emissions to manure application relative to synthetic N fertilizer application from individual studies and analyzed manure characteristics, experimental duration, climate, and soil properties as explanatory factors. Manure application significantly increased N2O emissions by an average 32.7% (95% confidence interval: 5.1–58.2%) compared to application of synthetic N fertilizer alone. The significant stimulation of N2O emissions occurred following cattle and poultry manure applications, subsurface manure application, and raw manure application. Furthermore, the significant stimulatory effects on N2O emissions were also observed for warm temperate climate, acid soils (pH < 6.5), and soil texture classes of sandy loam and clay loam. Average direct N2O emission factors (EFs) of 1.87% and 0.24% were estimated for upland soils and rice paddy soils receiving manure application, respectively. Although manure application increased SOC stocks, our study suggested that the benefit of increasing SOC stocks as GHG sinks could be largely offset by stimulation of soil N2O emissions and aggravated by CH4 emissions if, particularly for rice paddy soils, the stimulation of CH4 emissions by manure application was taken into account. The uncertain manure effects on N2O emissions constrain evaluation of the net climatic impact of manure application in arable lands. A global meta‐analysis was performed to quantify the overall responses of N2O emissions to manure application relative to synthetic N fertilizer in agricultural soils. Manure application on average significantly increased N2O emissions by 32.7% as compared to synthetic N fertilizer alone, and the sign and magnitude of N2O emissions were dependent on manure characteristics, climate, and soil properties. The benefit of C sequestration could be largely offset by stimulation of soil N2O emissions and aggravated by CH4 emissions if, particularly for rice paddy soils, the stimulation of CH4 emissions by manure application was taken into account.