摘要
选用田间开放式长期进行的夜间增温稻田(NW)、夜间常温+施加硅肥稻田(Si)、夜间增温+施硅稻田(NW+Si)以及夜间常温稻田(CK),分别采集耕层根际土和非根际土,设置4个氮添加处理,即NH^(+)_(4)-N、NO^(-)_(3)-N、酰胺态氮(尿素)和无氮,研究不同稻田土壤N_(2)O还原潜力对外源氮的响应特征。结果表明,4种稻田的根际土和非根际土在厌氧培养过程中N_(2)O浓度均随时间增长而下降,且变化趋势一致。在无氮添加条件下,NW处理稻田和Si处理稻田根际土的N_(2)O还原速率分别为19.2μg/(g·d)和16.6μg/(g·d),显著高于CK稻田(P<0.05),而对于非根际土而言三者之间无明显差异(P>0.05)。在添加NH^(+)_(4)-N或尿素条件下,Si处理稻田根际土的N_(2)O还原速率显著高于CK稻田(P<0.05),而对于非根际土则无明显差异(P>0.05)。在添加NO^(-)_(3)-N条件下,Si处理稻田非根际土的N_(2)O还原速率显著高于CK稻田(P<0.05)。综合来看,在施加氮肥条件下,特别在施加尿素条件下NW+Si处理稻田的N_(2)O还原速率显著高于NW处理稻田。因此,在未来气候变暖情景下,氮肥特别是尿素与硅肥配施可能是提高稻田土壤N_(2)O还原潜力的一条有效途径。
In this study,four types of paddy soils in long-term open field experiment,including night warming treatment(NW),normal temperature+silicon fertilizer treatment(Si),night warming+silicon fertilizer treatment(NW+Si)and normal temperature+no silicon fertilizer treatment(CK),were used to collect rhizosphere soil and non-rhizosphere soil.Four nitrogen addition treatments,namely NH^(+)_(4)-N,NO^(-)_(3)-N,amide nitrogen(urea)and no nitrogen,were set up to study the response characteristics of N_(2)O reduction potential in the four paddy soils to exogenous nitrogen addition.The results showed that the concentration of N_(2)O decreased with the increase of incubation time,and the change trends were consistent.Under the condition of no nitrogen addition,N_(2)O reduction rates of the rhizosphere soil in NW and Si paddy fields were 19.2μg/(g·d)and 16.6μg/(g·d),respectively,which were significantly higher than those in CK paddy field,whereas there was no significant difference in N_(2)O reduction rate of non-rhizosphere soil among the three paddy fields.Under the condition of NH^(+)_(4)-N or urea addition,the N_(2)O reduction rate of rhizosphere soil in Si paddy field was significantly higher than that in CK paddy field,but there was no significant difference for non-rhizosphere.Under the condition of NO^(-)_(3)-N addition,The N_(2)O reduction rate of non-rhizosphere soil in Si paddy field was significantly higher than that in CK paddy field.Comprehensively,N_(2)O reduction rate of NW+Si paddy field was significantly higher than that of NW paddy field under nitrogen application,especially under urea application.Therefore,in the future climate warming scenario,the combined application of nitrogen(especially urea)and silicon fertilizer may be an effective way to improve N_(2)O reduction potential in paddy soil.
作者
谢晴
饶旭东
周聪
薛梦琪
张耀鸿
XIE Qing;RAO Xu-dong;ZHOU Cong;XUE Meng-qi;ZHANG Yao-hong(Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters,Nanjing University of Information Science and Technology/Jiangsu Provincial Key Laboratory of Agricultural Meteorology,Nanjing 210044,China)
出处
《江苏农业学报》
CSCD
北大核心
2022年第1期87-93,共7页
Jiangsu Journal of Agricultural Sciences
基金
国家自然科学基金项目(41671247、41103039)
江苏省自然科学基金项目(BK20171455)
国家留学基金项目(201908320185)。
关键词
N_(2)O还原
夜间增温
硅肥
N_(2)O reduction
nighttime warming
silicon fertilizer