施肥措施对河套灌区土壤剖面N_2O的影响

Spatial and temporal distributions of soil profile N_2O as affected by different fertilization measures in Hetao Irrigation district

保证在不降低土壤肥力水平条件下,减缓农田N_2O排放,通过地下气体原位采集系统,于2016年5月~10月动态监测了河套灌区4种施肥措施(不施肥、常规施肥、常规施肥+生物炭、常规施肥+膨润土,分别标记为NF、CK、C、B)下0~80cm土层N_2O浓度变化。结果表明:各处理N_2O浓度峰值均出现于追肥、灌水后7~8天,施氮肥增加峰值,配施膨润土降低峰值;各处理不同土层N_2O浓度表现为80 cm>60 cm>40 cm>20 cm>10 cm。与CK相比,不施肥处理可显著降低各土层N_2O浓度,B处理可显著降低表层土壤N_2O浓度;C处理各土层N_2O浓度与CK无显著差异。综上所述,常规施肥基础上添加膨润土可显著降低表层土壤N_2O产生。

In order to reduce the N20 emission under the condition of not reducing soil fertility level, the N20 concentration in 0-80 cm soil layer of four kinds of fertilization measures （ no fertilization, conventional fertili- zation, conventional fertilization ＋ biochar, conventional fertilization ＋ bentonite, were marked as NF, CK, C, B） was dynamically monitored from underground gas in situ collection device from May to October in 2016. The results showed that the peak of each treated by N20 concentration appears after 7 to 8 days of top dressing or irrigation. Nitrogen fertilizer significantly increased the peak of N20 concentration, with bentonite can signifi- cantly reduce the peak N20 concentration. Foe each treatment the concentration of N20 in different soil layers was 80 cm 〉 60 cm 〉 40 cm 〉 20 cm 〉 10 cm. Compared with CK, N20 concentration could be significantly reduced by non - fertilization treatment, and the concentration of N20 in surface soil was significantly decreased by B treatment. The concentration of N20 in C treatment was not significantly the addition of bentonite on conventional fertilization could significantly reduce different from CK. In summary, N20 production in surface soil.