Journal article

Publication year: 2021

Journal: Soil Biology and Biochemistry

Volume number: 155

ISSN: 0038-0717

DOI Link: https://doi.org/10.1016/j.soilbio.2021.108158

Publisher: Elsevier

Abstract: 
Our understanding of how plants influence the gross rates of specific soil N transformations in plant-soil systems is still rudimentary, providing the incentive for our current study. A 15N tracing study was carried out with plants known for their NH4+-preference to quantify the gross soil N transformation and gross plant N uptake rates. Significant interactions between plants and gross rates of soil N transformations were observed. The rates of NH(4)(+ )uptake by sugarcane (3.74 mg N kg(-1)-d(-1)) and tea (3.34 mg N kg(-1)-d(-1)) were much higher than microbial NH(4)(+ )immobilization rates (0.01, and 0.27 mg N kg(-1)-d(-1), respectively), suggesting that NH(4)(+)preferring plants outcompeted microbial NH(4)(+ )acquisition. The gross rates of NO3 immobilization increased with decreasing gross NH4+ immobilization rates, indicating a switch towards microbial NO3 uptake under high plant NH(4)(+ )demand. Moreover, the gross rates of autotrophic nitrification, the classical NO3 production pathway, was generally low in the studied acidic soil (average 0.40 mg N kg(-1)-d(-1) in plant treatments), and was insufficient to meet the total NO3 demand (average 2.37 mg N kg(-1)-d(-1)). Gross rates of heterotrophic nitrification, ranging from 0.31 to 0.57 mg N kg(-1)-d(-1), were stimulated by the presence of plants and were generally responsible for 49-69% of total NO3 production in the plant treatments, while this rate was negligible in the absence of plant. Heterotrophic nitrification might provide additional NO3 to meet N requirements of plants and microorganisms. This is supported by the positive correlation of gross heterotrophic nitrification coupled with gross NO3 immobilization and plant N uptake rates. Interactions between plant N acquisition and soil N transformations exist and plant-soil studies are key to identify feedbacks between plants and soil microbes.

Harvard Citation style: He, X., Chi, Q., Zhao, C., Cheng, Y., Huang, X., Zhao, J., et al. (2021) Plants with an ammonium preference affect soil N transformations to optimize their N acquisition, Soil Biology and Biochemistry, 155, Article 108158. https://doi.org/10.1016/j.soilbio.2021.108158

APA Citation style: He, X., Chi, Q., Zhao, C., Cheng, Y., Huang, X., Zhao, J., Cai, Z., Zhang, J., & Müller, C. (2021). Plants with an ammonium preference affect soil N transformations to optimize their N acquisition. Soil Biology and Biochemistry. 155, Article 108158. https://doi.org/10.1016/j.soilbio.2021.108158