农业环境科学学报2012，Vol.31Issue(8)：1639-1646,8.
冬小麦/大葱轮作体系N2O排放特征及影响因素研究
Analysis of the Characteristics of Nitrous Oxide Emissions from a Winter Wheat-Green Onion Rotation System and the Influencing Factors
摘要
Abstract
Quantifying greenhouse gas< GHG ) emissions and searching for appropriate mitigation measures have become a relatively hot issue in international global climate change studies. Therefore, understanding the impacts of human activities on greenhouse gas emissions from productive soils is vital for mitigating negative effects on climate change. In this paper, N2O emissions in winter wheat-green onion rotation system were observed using static opaque chamber/gas chromatography(GC) method. The effects of relative environmental factors such as soil moisture and temperature etc. on N20 emissions were also discussed. The results indicated that the observed N20 emissions peaks followed each time of fertilizer application and irrigation or heavy rainfall. The frequency of the peaks in green onion growing season was higher than that in winter wheat. The highest N2O emission flux was observed in green onion growing season with 507.11 μg N·m‐2·h‐1. Annual cumulative N2O emissions in the 5 treatments of Control (CK), farmer's practice(FP), optimized fertilization (OPT), optimized fertilization +re-ducing fertilizer(OPT-N), and straw returned(C/N) were 1.71, 4.6, 3.62, 3.24 kg N·hm‐2and 3.02 kg N·hm‐2, respectively. The annual emission factor( EF) of N fertilizer ranged from 0.31% to 0.48%, with an average of 0.43%. The OPT-N and C/N treatments could reduce N2O emissions by 10% and 17%, respectively, comparing with OPT treatment. But the C/N treatment was regarded as the best management practice because it not only had significantly effect on reducing N2O emissions, but also maintaining crop yield. Multiple regression analysis revealed that soil temperature and soil moisture(WFPS) were also the factors affecting N2O emissions besides nitrogen fertilizer. When soil temperature changed in the range of 10-20 ℃, N2O emissions increased greatly with temperature rise, but soil temperature changed in the range of 20~30 ℃, soil moisture( WFPS ) became a limiting factor and there was a significant positive correlation between N2O emissions and soil moisture( WFPS). We expect these efforts will provide basic data for accurately predicting N2O emissions at regional scales that are attracting more attention across China.关键词
N2O排放/冬小麦/大葱轮作/影响因素Key words
nitrous oxide emissions/ winter wheat-green onion rotation/ influencing factors分类
资源环境引用本文复制引用
张静,李虎,王立刚,邱建军..冬小麦/大葱轮作体系N2O排放特征及影响因素研究[J].农业环境科学学报,2012,31(8):1639-1646,8.基金项目
公益性行业(农业)科研专项经费项目“农业源温室气体监测与控制技术研究”(201103039) （农业）
