Effect of gradual increase of atmospheric CO2 concentration on nitrification potential and communities of ammonia oxidizers in paddy fields. (1st January 2023)

• Record Type: Journal Article
• Authors: Ren, Bing-jie; Shen, Li-dong; Liu, Xin; Jin, Jing-hao; Huang, He-chen; Tian, Mao-hui; Yang, Yu-ling; Yang, Wang-ting; Liu, Jia-qi; Geng, Cai-yu; Wu, Hong-sheng; Hu, Zheng-hua
• Is Part Of: Journal of environmental management. Volume 325:Part A(2023)
• Publication Date: 2023-01-01
• Subjects: Gradual increase -- Ammonia-oxidizers -- Positive influence -- Paddy ecosystem; Environmental policy -- Periodicals; Environmental management -- Periodicals; Environment -- Periodicals; Ecology -- Periodicals; 363.705
• DOI: 10.1016/j.jenvman.2022.116597
• Languages: English
• ISSNs: 0301-4797

Abstract

Abstract: Currently, the influence of elevated atmospheric CO2 concentration (eCO2 ) on ammonia oxidation to nitrite, the rate-limiting step of nitrification in paddy soil, is poorly known. Previous studies that simulate the effect of eCO2 on nitrification are primarily based on an abrupt increase of atmospheric CO2 concentration. However, paddy ecosystems are experiencing a gradual increase of CO2 concentration. To better understand how the nitrification potential, abundance and communities of ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB) respond to eCO2 in paddy ecosystems, a field experiment was conducted using the following two treatments: a gradual increase of CO2 (EC, increase of 40 ppm per year until 200 ppm above ambient) and ambient CO2 (CK). The results demonstrated that the EC treatment significantly ( P < 0.05) stimulated the soil potential nitrification rate (PNR) at the jointing and milky stages, which increased by 127.83% and 27.35%, respectively, compared with CK. Furthermore, the EC treatment significantly ( P < 0.05) stimulated the AOA and AOB abundance by 56.60% and 133.84%, respectively, at the jointing stage. Correlation analysis showed that the PNR correlated well with the abundance of AOB ( R 2 = 0.7389, P < 0.001). In addition, the EC treatment significantly ( P < 0.05) altered the community structure of AOB, while it had little effect on that of AOA. A significant difference in the proportion of Nitrosospira was observed between CO2 treatments. In conclusion, the gradual increase of CO2 positively influenced the PNR and abundance of ammonia oxidizers, and AOB could be more important than AOA in nitrification under eCO2 . Graphical abstract: Image 1 Highlights: Gradual CO2 increase significantly stimulated the overall PNR by 42.0%. Gradual CO2 increase increased AOA and AOB abundance by 20.5% and 70.5%, respectively. Gradual CO2 increase decreased the proportion of Nitrosospira by 21.1%. Gradual CO2 increase significantly altered the community structure of AOB. AOB could play a more important role than AOA in nitrification under rising CO2 .