Bai Jin-Ze, Liu Zhen-Yuan, Song Jia-Jie, Li Na, Yu Qi, Hao Jia-Qi, Xu Hong-Wei, Cheng Bo-Hao, Wang Xing, Feng Yong-Zhong
College of Agronomy, North A&F University, Yangling 712100, China.
Research Center of Recycle Agricultural Engineering and Technology of Shaanxi Province, Yangling 712100, China.
Huan Jing Ke Xue. 2022 Aug 8;43(8):4379-4386. doi: 10.13227/j.hjkx.202112061.
Here, we investigated the effects of straw returning combined with biochar application on summer maize yield and soil nitrous oxide (NO) emissions, based on a field location trial in the Guanzhong Plain from 2019 to 2020. The soil NO emission rates were monitored using the static chamber-chromatography method. A comprehensive analysis of summer maize yields, soil NO emissions, and soil labile nitrogen components was conducted to clarify the effects of straw returning combined with biochar application on improving soil fertility, increasing summer maize yield, and reducing greenhouse gas emissions. The three treatments were no straw returning (S), straw returning (S), and straw returning combined with biochar application (SB). The results showed that the peak of NO emissions from each treatment occurred 10 d after the straw return, and the rate of soil NO emissions remained at a low level after 30 d of straw return. The rate of soil NO emissions showed highly significant positive correlations (<0.05) with ammonium nitrogen (NH-N), inorganic nitrogen (SIN), microbial nitrogen (MBN), and dissolved organic nitrogen (DON) contents. S significantly increased summer maize yield, cumulative NO emissions, yield-scaled NO intensity, and total nitrogen (TN) content by 7.4%-13%, 65.8%-132.2%, 54.6%-103%, and 27.8%-33%, respectively, compared to those in S. Although the trend for SB to increase summer maize yield (2.5%-3.3%) compared to that in S was not significant (>0.05), SB significantly reduced cumulative NO emissions and yield-scaled NO intensity by 24.0%-27.3% and 26.4%-29.2%, respectively, compared to that in S. SB significantly reduced the rate of soil NO emissions by 45.1%-69.6% at the peak of NO emissions compared to that in S. Biochar application mitigated soil NO emissions induced by straw return and had a peak-shaving effect. SB significantly increased soil total N by 9.1%-12.2% compared to that in S. Combining summer maize yield, soil NO emissions, and TN content, SB not only improved soil fertility and summer maize yield but also reduced yield-scaled NO intensity, making it a suitable management practice that can be replicated to balance crop yield and environmental friendliness.
在此，基于2019年至2020年在关中平原进行的田间定位试验，我们研究了秸秆还田结合施用生物炭对夏玉米产量和土壤一氧化二氮（N₂O）排放的影响。采用静态箱-色谱法监测土壤N₂O排放速率。对夏玉米产量、土壤N₂O排放和土壤活性氮组分进行综合分析，以阐明秸秆还田结合施用生物炭对提高土壤肥力、增加夏玉米产量和减少温室气体排放的影响。三种处理分别为不秸秆还田（S）、秸秆还田（R）和秸秆还田结合施用生物炭（SB）。结果表明，各处理的N₂O排放峰值出现在秸秆还田后10天，秸秆还田30天后土壤N₂O排放速率保持在较低水平。土壤N₂O排放速率与铵态氮（NH₄⁺-N）、无机氮（SIN）、微生物氮（MBN）和溶解有机氮（DON）含量呈极显著正相关（P<0.05）。与S相比，R显著提高了夏玉米产量、累积N₂O排放量、产量尺度N₂O强度和全氮（TN）含量，分别提高了7.4%-13%、65.8%-132.2%、54.6%-103%和27.8%-33%。虽然与R相比，SB提高夏玉米产量（2.5%-3.3%）的趋势不显著（P>0.05），但与R相比，SB显著降低了累积N₂O排放量和产量尺度N₂O强度，分别降低了24.0%-27.3%和26.4%-29.2%。在N₂O排放峰值时，与R相比，SB显著降低了土壤N₂O排放速率45.1%-69.6%。施用生物炭减轻了秸秆还田引起的土壤N₂O排放，并具有削峰效应。与R相比，SB显著提高了土壤全氮9.1%-12.2%。综合夏玉米产量、土壤N₂O排放和TN含量来看，SB不仅提高了土壤肥力和夏玉米产量，还降低了产量尺度N₂O强度，是一种可推广应用以平衡作物产量和环境友好性的适宜管理措施。
