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Zeng Q, Zhang Q, Fan Y, Gao Y, Yuan X, Zhou J, Dai H, Chen Y. Phosphorus availability regulates nitrogen fixation rate through a key diazotrophic assembly: Evidence from a subtropical Moso bamboo forest subjected to nitrogen application. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 912:169740. [PMID: 38160820 DOI: 10.1016/j.scitotenv.2023.169740] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Revised: 12/08/2023] [Accepted: 12/26/2023] [Indexed: 01/03/2024]
Abstract
Biological N fixation (BNF) is an important N input process for terrestrial ecosystems. Long-term N application increases the availability of N, but may also lead to phosphorus (P) deficiency or an imbalance between N and P. Here, we performed a 5-year N application experiment in a subtropical Phyllostachys heterocycla forest in site and a P application experiment in vitro to investigate the effect of N application on the BNF rate and its regulatory factor. The BNF rate, nifH gene, free-living diazotrophic community composition and plant properties were measured. We found that N application suppressed the BNF rate and nifH gene abundance, whereas the BNF rate in soils with added P was significantly higher overall than that in soils without added P. Moreover, we identified a key diazotrophic assembly (Mod#2), primarily comprising Bradyrhizobium, Geobacter, Desulfovibrio, Anaeromyxobacter, and Pseudodesulfovibrio, which explained 77 % of the BNF rate variation. There was a significant positive correlation between the Mod#2 abundance and soil available P, and the random forest results showed that soil available P is the most important factor affecting the Mod#2 abundance. Our findings highlight the importance of soil P availability in regulating the activities of key diazotrophs, and thus increasing P supply may help to promote N accumulation and primary productivity through facilitating the BNF process in forest ecosystems.
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Affiliation(s)
- Quanxin Zeng
- School of Geographical Sciences, Fujian Normal University, Fuzhou 350007, China; State Key Laboratory of Subtropical Mountain Ecology (Funded by the Ministry of Science and Technology and Fujian Province), Fujian Normal University, Fuzhou 350007, China
| | - Qiufang Zhang
- School of Geographical Sciences, Fujian Normal University, Fuzhou 350007, China; State Key Laboratory of Subtropical Mountain Ecology (Funded by the Ministry of Science and Technology and Fujian Province), Fujian Normal University, Fuzhou 350007, China.
| | - Yuexin Fan
- School of Geographical Sciences, Fujian Normal University, Fuzhou 350007, China; State Key Laboratory of Subtropical Mountain Ecology (Funded by the Ministry of Science and Technology and Fujian Province), Fujian Normal University, Fuzhou 350007, China
| | - Yanli Gao
- School of Geographical Sciences, Fujian Normal University, Fuzhou 350007, China; State Key Laboratory of Subtropical Mountain Ecology (Funded by the Ministry of Science and Technology and Fujian Province), Fujian Normal University, Fuzhou 350007, China
| | - Xiaochun Yuan
- College of Tourism, Wuyi University, Wuyishan 354300, China
| | - Jiacong Zhou
- State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710061, China
| | - Hui Dai
- School of Geographical Sciences, Fujian Normal University, Fuzhou 350007, China; State Key Laboratory of Subtropical Mountain Ecology (Funded by the Ministry of Science and Technology and Fujian Province), Fujian Normal University, Fuzhou 350007, China
| | - Yuehmin Chen
- School of Geographical Sciences, Fujian Normal University, Fuzhou 350007, China; State Key Laboratory of Subtropical Mountain Ecology (Funded by the Ministry of Science and Technology and Fujian Province), Fujian Normal University, Fuzhou 350007, China.
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