利用静态箱-气相色谱法对长江流域稻麦轮作系统下稻田N2O排放进行田间原位观测,研究了配施腐秆剂(瑞莱特催腐剂和金葵子腐秆剂)对水稻生长季N2O排放的影响,旨在为腐秆剂与秸秆配施条件下稻田N2O排放规律的研究提供科学依据.结果表明:配施腐秆剂对稻田N2O排放的季节变化趋势无明显影响,但腐秆剂与秸秆配施可降低水稻生育期N2O排放总量;与单施秸秆相比,配施瑞莱特和金葵子腐秆剂处理N2O排放总量分别下降12.7%和8.9%(p〉0.05);水稻全生育期内,仅施秸秆、秸秆与瑞莱特配施和秸秆与金葵子配施处理N2O平均排放通量依次为63.35、55.30和57.68 μg·m-2 h-1(以N计).N2O排放主要集中在烤田期与复水后干湿交替阶段.全生育期内,N2O排放通量与土壤温度间无显著相关性(p〉0.05).
A field experiment was conducted to investigate the effects of straw-decomposing microbial inoculants on the N2O flux from paddy fields under a rice-wheat rotation system during the rice growing season in the Yangtze River Valley. Seasonal variation of N2O flux was monitored using the method of static chamber-gas chromatography. Three treatments, i.e. even incorporation of wheat straw (S), incorporation of wheat straw treated with Ruilaite inoculant (SR), and incorporation of wheat straw treated with Jinkuizi inoculant (SJ), were tested in the experiment. Results show that the microbial inoculants did not show significant effect on seasonal variation of N2O flux, but did decrease the total N2O emission during the rice growing season by 12.7% in Treatment SR and 8.9% in Treatment SJ as compared with Treatment S. The mean N2O flux was 63.35, 57.68 and 55.30 μg m-2 h-1 for Treatment S, SJ and SR, respectively. N2O emissions mainly occurred during the midseason aeration period and the dry-wet alternation stage after re-flooding. No significant correlation was observed between N2O flux and soil temperature at depth of 5, 10, and 15 cm (p〉0.05).