Processes and factors controlling N₂O production in an intensively managed low carbon calcareous soil under sub-humid monsoon conditions.
An automated system for continuous measurement of N₂O fluxes on an hourly basis was employed to study N₂O emissions in an intensively managed low carbon calcareous soil under sub-humid temperate monsoon conditions. N₂O emissions occurred mainly within two weeks of application of NH₄(+) based fertilizer and total N₂O emissions in wheat (average 0.35 or 0.21 kg N ha⁻¹ season⁻¹) and maize (average 1.47 or 0.49 kg N ha⁻¹ season⁻¹) under conventional and optimum N fertilization (300 and 50-122 kg N ha⁻¹, respectively) were lower than previously reported from low frequency measurements. Results from closed static chamber showed that N₂O was produced mainly from nitrification of NH₄(+)-based fertilizer, with little denitrification occurring due to limited readily oxidizable carbon and low soil moisture despite consistently high soil nitrate-N concentrations. Significant reductions in N₂O emissions can be achieved by optimizing fertilizer N rates, using nitrification inhibitors, or changing from NH₄(+)- to NO₃(-)-based fertilizers.
Key Laboratory of Plant Nutrition, Chinese Ministry of Agriculture, and College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China.
Xiaotang
X
Ju
Xing
X
Lu
Zhiling
Z
Gao
Xinping
X
Chen
Fang
F
Su
Martin
M
Kogge
Volker
V
Römheld
Peter
P
Christie
Fusuo
F
Zhang
D000383:Agriculture / Q000379:methods; D000397:Air Pollution / Q000032:analysis / Q000517:prevention & control; D002244:Carbon / Q000378:metabolism; D002681:China; D058440:Denitrification; D004784:Environmental Monitoring; D005308:Fertilizers; D058465:Nitrification; D009609:Nitrous Oxide / Q000032:analysis*; D000644:Quaternary Ammonium Compounds / Q000378:metabolism*; D012987:Soil / Q000737:chemistry; D014908:Triticum / Q000378:metabolism*; D014887:Weather; D003313:Zea mays / Q000378:metabolism*
D005308:Fertilizers; D000644:Quaternary Ammonium Compounds; D012987:Soil; D002244:Carbon; D009609:Nitrous Oxide