Can phosphorus and nitrogen addition affect ammonia oxidizers in a high-phosphorus agricultural soil?

ABSTRACT

Ammonia-oxidizing archaea (AOA) and bacteria (AOB), which convert NH₃ to NO₂⁻ in soils, are important for agricultural production. It is well known that N addition can strongly affect soil ammonia oxidizers, but little is known about P addition. Based on microcosm experiments, this study assessed the responses of ammonia oxidizers to chemical P addition in a typically high P agricultural soil with or without N supply. Six treatments examined were neither N nor P, P alone (0.15, 0.45, and 0.75 g P₂O₅ kg⁻¹ soil, respectively), N alone (0.25 g N kg⁻¹ soil), and N plus P (0.25 g N and 0.15 g P₂O₅ kg⁻¹ soil). Quantitative real-time PCR for the abundance and high-throughput sequencing for community structure were applied. The results revealed that P addition did not affect the abundances and community structures of AOA and AOB, but N addition significantly increased AOB abundance and alter its community structure. Without N supply, continuously increasing soil P availability did not affect these two groups of ammonia oxidizers. This study highlights the relationship between soil P availability and ammonia oxidizers and suggests that soil P availability could be as a potential indicator for predicting N-related ecosystem functions in agricultural production.

KEYWORDS:

• Soil ammonia oxidizers
• amoA gene
• phosphorus
• nitrogen
• potential nitrification rate

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the National Natural Science Foundation of China (grant number 41601250).