Journal article

Authors list: Tang, Quan; Wang, Jing; Cao, Miaomiao; Chen, Zhaoxiong; Tu, Xiaoshun; Elrys, Ahmed S; Jing, Hang; Wang, Xiaozhi; Cai, Zucong; Müller, Christoph; Daniell, Tim J; Yan, Xiaoyuan; Cheng, Yi

Publication year: 2024

Journal: Agriculture, Ecosystems and Environment

Volume number: 362

ISSN: 0167-8809

eISSN: 1873-2305

DOI Link: https://doi.org/10.1016/j.agee.2023.108848

Publisher: Elsevier

Abstract: 
Soil microbial immobilization of nitrate (NO3--N, I-NO3) and its role in mitigating NO3--N pollution in agricultural ecosystems globally is often neglected because of the tenet that microbes preferentially use ammonium over NO3--N. Soil I-NO3 driven by heterotrophic microorganisms is often carbon (C)-limited, and may therefore be stimulated by C sources with high C/nitrogen (N) ratios. Here, using (NO3-)-N-15-N labelling coupled with acetylene inhibition, quantitative PCR and Illumina high-throughput sequencing approaches, we demonstrated that I-NO3 was stimulated from zero to a substantial level by crop residue amendment without any environmental risk; the degree of stimulation depending on residue quality and soil type. The stimulation was predicted well by C mineralization of the added residue. Soil with a lower initial nutrient status had reduced I-NO3 efficiency due to stronger C constraint and lower return on energy investment. Fast-growing bacterial r-strategists were identified as the key driver of I-NO3. We estimate that, globally, residue amendment could cause a total NO3--N loss reduction of about 33.6 Tg N yr(-1) through I-NO3 stimulation. We suggest that soil I-NO3 driven by addition of exogenous C is an overlooked process that can help curb NO3--N accumulation in soil and its subsequent release to the environment, the "nitrate time bomb".

Harvard Citation style: Tang, Q., Wang, J., Cao, M., Chen, Z., Tu, X., Elrys, A., et al. (2024) Awakening soil microbial utilization of nitrate by carbon regulation to lower nitrogen pollution, Agriculture, Ecosystems and Environment, 362, Article 108848. https://doi.org/10.1016/j.agee.2023.108848

APA Citation style: Tang, Q., Wang, J., Cao, M., Chen, Z., Tu, X., Elrys, A., Jing, H., Wang, X., Cai, Z., Müller, C., Daniell, T., Yan, X., & Cheng, Y. (2024). Awakening soil microbial utilization of nitrate by carbon regulation to lower nitrogen pollution. Agriculture, Ecosystems and Environment. 362, Article 108848. https://doi.org/10.1016/j.agee.2023.108848