Keyi Zhang, Wangying Ding, Xiran Zhao, Jun Li, Guixin Chu, Rui Tao
{"title":"The cooperative interaction of AOB and comammox clade A drives nitrification and N2O emissions in a long-term organic fertilized paddy soil","authors":"Keyi Zhang, Wangying Ding, Xiran Zhao, Jun Li, Guixin Chu, Rui Tao","doi":"10.1016/j.apsoil.2024.105451","DOIUrl":null,"url":null,"abstract":"<div><p>The newly discovered complete ammonia oxidizer (comammox <em>Nitrospira</em>) is able to single-step nitrification capability, and increased our understanding of soil nitrogen cycling. However, the response of comammox and ammonia-oxidizing bacteria (AOB) and archaea (AOA) to long-term fertilization and rhizosphere effects in paddy soils and their relative contribution to the nitrification-derived N<sub>2</sub>O emissions is still unclear. Here, we collected rhizosphere and bulk soils with thirty years of different fertilization strategies, i.e., non-fertilization (CK), chemical N, P, and K application (NPK), and NPK plus pig manure application (NPKM), respectively, to test changes in nitrification potential rate (PNR), N<sub>2</sub>O emission fluxes, abundance of ammonia oxidizers and their significant drivers. The result showed that NPKM significantly increased soil C and N levels, the proportion of soil middle-size particles (40.35–148.00 μm class), and soil PNR, but decreased soil N<sub>2</sub>O emissions, especially in the drying time of paddy (<em>P</em> < 0.05), compared to NPK fertilization. NPKM had the highest values of AOA, AOB, and comammox clade A <em>amoA</em> gene copy numbers (<em>P</em> < 0.05), but clade B was increased by the NPK in the rhizosphere soil. Furthermore, fertilization showed greater effects on ammonia oxidizers (except for clade B) than the rhizosphere effect. Mantel test showed that SOM, TP, pH, NH<sub>4</sub><sup>+</sup>, and NO<sub>3</sub><sup>−</sup> were main abiotic factors causing the niche separation among ammonia oxidizers. Linear regression analysis and structural equation model (SEM) showed that both PNR and N<sub>2</sub>O emission fluxes were significantly associated with the abundance of AOB and comammox clade A (<em>P</em> < 0.05). Therefore, our results underline the importance of AOB together with comammox clade A in nitrification and N<sub>2</sub>O production in long-term organic fertilized paddy fields, which could provide new ideas for the mitigation of N<sub>2</sub>O emission by adopting organic fertilization scenarios in Chinese paddy fields.</p></div>","PeriodicalId":8099,"journal":{"name":"Applied Soil Ecology","volume":null,"pages":null},"PeriodicalIF":4.8000,"publicationDate":"2024-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Applied Soil Ecology","FirstCategoryId":"97","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0929139324001823","RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"SOIL SCIENCE","Score":null,"Total":0}
引用次数: 0
Abstract
The newly discovered complete ammonia oxidizer (comammox Nitrospira) is able to single-step nitrification capability, and increased our understanding of soil nitrogen cycling. However, the response of comammox and ammonia-oxidizing bacteria (AOB) and archaea (AOA) to long-term fertilization and rhizosphere effects in paddy soils and their relative contribution to the nitrification-derived N2O emissions is still unclear. Here, we collected rhizosphere and bulk soils with thirty years of different fertilization strategies, i.e., non-fertilization (CK), chemical N, P, and K application (NPK), and NPK plus pig manure application (NPKM), respectively, to test changes in nitrification potential rate (PNR), N2O emission fluxes, abundance of ammonia oxidizers and their significant drivers. The result showed that NPKM significantly increased soil C and N levels, the proportion of soil middle-size particles (40.35–148.00 μm class), and soil PNR, but decreased soil N2O emissions, especially in the drying time of paddy (P < 0.05), compared to NPK fertilization. NPKM had the highest values of AOA, AOB, and comammox clade A amoA gene copy numbers (P < 0.05), but clade B was increased by the NPK in the rhizosphere soil. Furthermore, fertilization showed greater effects on ammonia oxidizers (except for clade B) than the rhizosphere effect. Mantel test showed that SOM, TP, pH, NH4+, and NO3− were main abiotic factors causing the niche separation among ammonia oxidizers. Linear regression analysis and structural equation model (SEM) showed that both PNR and N2O emission fluxes were significantly associated with the abundance of AOB and comammox clade A (P < 0.05). Therefore, our results underline the importance of AOB together with comammox clade A in nitrification and N2O production in long-term organic fertilized paddy fields, which could provide new ideas for the mitigation of N2O emission by adopting organic fertilization scenarios in Chinese paddy fields.
期刊介绍:
Applied Soil Ecology addresses the role of soil organisms and their interactions in relation to: sustainability and productivity, nutrient cycling and other soil processes, the maintenance of soil functions, the impact of human activities on soil ecosystems and bio(techno)logical control of soil-inhabiting pests, diseases and weeds.