【中国蔬菜种植的N2O年排放通量】Qiaohui Liu Yanmei Qin Jianwen Zou Yanqin Guo Zhiliang Gao. Annual nitrous oxide emissions from open-air and greenhouse vegetable cropping systems in China. Plant and Soil
Abstract
Aims
A field experiment was conducted to quantify annual nitrous oxide (N2O) fluxes from control and fertilized plots under open-air and greenhouse vegetable cropping systems in southeast China. We compiled the reported global field annual N2O flux measurements to estimate the emission factor of N fertilizer for N2O and its background emissions from vegetable fields.
Methods
Fluxes of N2O were measured using static chamber-GC techniques over the 2010–2011 annual cycle with multiple cropping seasons.
Results
The mean annual N2O fluxes from the controls were 46.1 ± 2.3 μg N2O-N m−2 hr−1 and 68.3 ± 4.1 μg N2O-N m−2 hr−1 in the open-air and greenhouse vegetable systems respectively. For the plots receiving 900 kg N ha−1 annual N2O emissions averaged 90.6 ± 8.9 μg N2O-N m−2 hr−1 and 106.4 ± 6.6 μg N2O-N m−2 hr−1 in the open-air and greenhouse vegetable systems respectively. By pooling published field N2O flux measurements taken over or close to a full year the N2O emission factor for N fertilizer averaged 0.63 ± 0.09 % with a background emission of 2.67 ± 0.80 kg N2O-N ha−1 in Chinese vegetable fields. Annual N2O emissions from Chinese vegetable systems were estimated to be 84.7 Gg N2O-N yr−1 consisting of 72.5 Gg N2O-N yr−1 and 12.2 Gg N2O-N yr−1 in the open-air and greenhouse vegetable systems respectively.
Conclusions
While N2O emissions from the greenhouse vegetable cropping system tended to be slightly higher compared to the open-air system in our
