How does biochar influence soil nitrification and nitrification-induced N2O emissions?

Qi Liu; Yaxin Wu; Jing Ma; Jiang Jiang; Xinyi You; Runjin Lv; Sijing Zhou; Chang Pan; Benjuan Liu; Qiao Xu; Zubin Xie

doi:10.1016/j.scitotenv.2023.168530

How does biochar influence soil nitrification and nitrification-induced N₂O emissions?

Sci Total Environ. 2024 Jan 15:908:168530. doi: 10.1016/j.scitotenv.2023.168530. Epub 2023 Nov 13.

Authors

Qi Liu¹, Yaxin Wu², Jing Ma³, Jiang Jiang², Xinyi You², Runjin Lv², Sijing Zhou², Chang Pan², Benjuan Liu⁴, Qiao Xu⁵, Zubin Xie⁶

Affiliations

¹ Co-Innovation Center for Sustainable Forestry in Southern China, Nanjing Forestry University, No. 159, Longpan Road, Nanjing 210037, China. Electronic address: liuqihy@njfu.edu.cn.
² Co-Innovation Center for Sustainable Forestry in Southern China, Nanjing Forestry University, No. 159, Longpan Road, Nanjing 210037, China.
³ Department of Agronomy and Horticulture, Jiangsu Vocational College of Agriculture and Forestry, No. 19, East Wenchang Road, Jurong 212400, China. Electronic address: majing01@tyut.edu.cn.
⁴ Department of Environmental Engineering, Taizhou University, Taizhou, Zhejiang 318000, China.
⁵ College of Environmental Science and Engineering, Yangzhou University, No. 196 Huayang Xi Road, Yangzhou 225127, China.
⁶ State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, No.71 Beijing Dong Road, Nanjing 210008, China.

PMID: 37963541
DOI: 10.1016/j.scitotenv.2023.168530

Abstract

Nitrification is a major pathway of N₂O production, especially in aerobic soils. The amendment of soils with biochar has been suggested as a promising solution to regulate soil N cycle and reduce N₂O emissions. However, there is a lack of comprehensive and quantitative understanding of biochar impacts on soil nitrification and nitrification-induced N₂O emissions. In this study, a meta-analysis was conducted using data compiled across 95 peer-reviewed studies. Results showed that biochar in general significantly increased soil nitrification rate by 56 %, with overall no significant effect on nitrification-induced N₂O emissions, suggesting that biochar likely restricted the fraction of nitrified N emitted as N₂O emissions. The abundance of ammonia-oxidizing bacteria (AOB) was significantly increased by 37 % following biochar addition, but that of ammonia-oxidizing archaea (AOA) did not change significantly, indicating that the impact of biochar on AOB rather than AOA may play an important role in soil nitrification. The impacts of biochar on soil nitrification processes were heterogeneous depending on soil properties. Biochar increased soil nitrification rate and AOB abundance to a larger extent in poorly pH-buffered soils such as those with acidic pH (<5), low organic carbon (<10 g kg^-1), or poor texture (rich in either sand or clay), which may be attributed to the liming and structural effects of biochar that regulate soil pH and water-air status. The overall no significant effect of biochar on nitrification-induced N₂O emissions was due to a positive effect in acidic soils, a negative effect in alkaline soils, and little effect in neutral soils. This study provides a comprehensive insight into how different factors mediate the response of soil nitrification processes to biochar amendment, which contributes to a new understanding of biochar function in regulating soil N₂O emissions, and can assist in designing biochar projects that would benefit soil N cycle while minimizing undesirable side effects.

Keywords: Ammonia oxidizer; Biochar; Meta-analysis; N(2)O emissions; Nitrification.

Publication types

Meta-Analysis

MeSH terms

Ammonia / metabolism
Archaea / metabolism
Nitrification*
Nitrous Oxide / analysis
Soil Microbiology
Soil* / chemistry

Substances

Soil
biochar
Ammonia
Nitrous Oxide