Straw-Increased C/N Ratio Mitigates Nitrate Leaching in Fluvial Soil by Enhancing Microbial N Pool and Reducing N Mineralization
Abstract
1. Introduction
2. Materials and Methods
2.1. Experimental Soil
2.2. Experimental Design
2.3. Soil and Leachate Properties Analysis
2.4. Soil Microbial Biomass
2.5. Soil Enzyme Activities
2.6. Soil C and N Transformation Rates
2.7. Soil 16S rRNA, 18S rRNA and N Functional Genes
2.8. Statistical Analysis
3. Results
3.1. NH4+-N and NO3−-N in Soil and Leachate
3.2. Soil Total N, Microbial Biomass N and Labeled Fertilizer 15N Distribution
3.3. Soil Dissolved Organic C and N and Their Related Transformation Rates
3.4. Soil Microbial Biomass C and Abundance of N-Functional Genes
3.5. Soil Enzyme Activities Related to C and N Transformations
3.6. Principal Component Analysis of Soil Indicators
3.7. Structural Equation Modeling of Key Factors Affecting NO3−-N Leaching
4. Discussion
4.1. Effects of Straw-Increased C/N Ratio on Enhancing Soil N Storage and Minimizing N Losses
4.2. Effects of Increasing C/N Ratio on C and N Transformation Enzymes
4.3. Effects of Increasing the C/N Ratio on N Transformation Rates
5. Conclusions
Supplementary Materials
Author Contributions
Funding
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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Hu, Y.; Zhao, C.; Zhang, W.; Zhao, P.; Qin, S.; Zhang, Y.; Sui, F. Straw-Increased C/N Ratio Mitigates Nitrate Leaching in Fluvial Soil by Enhancing Microbial N Pool and Reducing N Mineralization. Agronomy 2025, 15, 2371. https://doi.org/10.3390/agronomy15102371
Hu Y, Zhao C, Zhang W, Zhao P, Qin S, Zhang Y, Sui F. Straw-Increased C/N Ratio Mitigates Nitrate Leaching in Fluvial Soil by Enhancing Microbial N Pool and Reducing N Mineralization. Agronomy. 2025; 15(10):2371. https://doi.org/10.3390/agronomy15102371
Chicago/Turabian StyleHu, Yuhan, Chunyuan Zhao, Wenwen Zhang, Peng Zhao, Shiyu Qin, Yupeng Zhang, and Fuqing Sui. 2025. "Straw-Increased C/N Ratio Mitigates Nitrate Leaching in Fluvial Soil by Enhancing Microbial N Pool and Reducing N Mineralization" Agronomy 15, no. 10: 2371. https://doi.org/10.3390/agronomy15102371
APA StyleHu, Y., Zhao, C., Zhang, W., Zhao, P., Qin, S., Zhang, Y., & Sui, F. (2025). Straw-Increased C/N Ratio Mitigates Nitrate Leaching in Fluvial Soil by Enhancing Microbial N Pool and Reducing N Mineralization. Agronomy, 15(10), 2371. https://doi.org/10.3390/agronomy15102371
 
        


