Can the co-application of biochar and different inorganic nitrogen fertilizers repress N2O emissions in acidic soil?

Yuxuan Li; Riaz Muhammad; Babar Saba; Hao Xia; Xiangling Wang; JiYuan Wang; Cuncang Jiang

doi:10.1016/j.envres.2023.116217

Can the co-application of biochar and different inorganic nitrogen fertilizers repress N₂O emissions in acidic soil?

Environ Res. 2023 Aug 15;231(Pt 3):116217. doi: 10.1016/j.envres.2023.116217. Epub 2023 May 26.

Authors

Yuxuan Li¹, Riaz Muhammad², Babar Saba¹, Hao Xia¹, Xiangling Wang³, JiYuan Wang¹, Cuncang Jiang⁴

Affiliations

¹ Microelement Research Center, College of Resources and Environment, Huazhong Agricultural University, Wuhan, Hubei, 430070, PR China.
² College of Resources and Environment, Zhongkai University of Agriculture and Engineering, Guangzhou, 510225, PR China.
³ Microelement Research Center, College of Resources and Environment, Huazhong Agricultural University, Wuhan, Hubei, 430070, PR China; The Key Laboratory of Oasis Ecoagriculture, Xinjiang Production and Construction Corps, Shihezi University, Shihezi, Xinjiang, 832000, PR China.
⁴ Microelement Research Center, College of Resources and Environment, Huazhong Agricultural University, Wuhan, Hubei, 430070, PR China; The Key Laboratory of Oasis Ecoagriculture, Xinjiang Production and Construction Corps, Shihezi University, Shihezi, Xinjiang, 832000, PR China. Electronic address: jcc2000@mail.hzau.edu.cn.

PMID: 37245574
DOI: 10.1016/j.envres.2023.116217

Abstract

The sole application of nitrogen (N) fertilizer with lower N₂O emission potential or combined with biochar may help for mitigating N₂O production. However, how biochar applied with various inorganic N fertilizers affected N₂O emission in acidic soil remains unclear. Thus, we examined N₂O emission, soil N dynamics and relating nitrifiers (i.e., ammonia-oxidizing archaea, AOA) in acidic soil. The study contained three N fertilizers (including NH₄Cl, NaNO₃, NH₄NO₃) and two biochar application rates (i.e., 0% and 0.5%). The results indicated that the alone application of NH₄Cl produced more N₂O. Meanwhile, the co-application of biochar and N fertilizers enhanced N₂O emission as well, especially in the combined treatment of biochar and NH₄NO₃. Soil pH was decreased with the application of various N fertilizers, especially with NH₄Cl, and the average decrease rate was 9.6%. Meanwhile, correlation analysis showed a negative relationship between N₂O and pH, dramatically, which might indicate that the alteration of pH was one factor relating to N₂O emission. However, there was no difference between the same N addition treatments with or without biochar on pH. Interestingly, in the combined treatment of biochar and NH₄NO₃, the lowest net nitrification rate and net mineralization rate appeared during days 16-23. Meanwhile, the highest emission rate of N₂O in the same treatment also appeared during days 16-23. The accordance might indicate that N transformation alteration was another factor relating to N₂O emissions. In addition, compared to NH₄NO₃ alone application, co-applied with biochar had a lower content of Nitrososphaera-AOA, which was a main contributor to nitrification. The study emphasizes the importance of using a suitable form of N fertilizers and further indicates that two factors, namely alteration of pH and N transformation rate, are related to N₂O emission. Moreover, in future studies, it is necessary to explore the soil N dynamics controlled by microorganisms.

Keywords: Acidic soil; Biochar; N(2)O emissions; Nitrogen fertilizers; Soil N dynamics.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Agriculture / methods
Archaea
Fertilizers* / analysis
Nitrogen
Nitrous Oxide
Soil* / chemistry

Substances

Soil
Fertilizers
Nitrogen
biochar
Nitrous Oxide