Sun Hongyang, Yu Dong, Zhou Jun, Chen Yang
Sichuan Zoige Alpine Wetland Ecosystem National Observation and Research Station, Southwest Minzu University, Chengdu, China.
Sichuan Provincial Grassland Technology Research and Extension Center, Chengdu, China.
Nat Commun. 2025 Jul 31;16(1):7028. doi: 10.1038/s41467-025-62425-2.
Understanding N-P interactions is crucial for co-limitation in ecosystems but remains unclear due to oversimplified frameworks. Here, a large-scale N and P addition experiment in early soils revealed four key processes driving nutrient coupling, emphasizing carbon's central role. N addition significantly increases P availability. P availability drives biological N fixation. Both nutrients stimulate carbon fixation, with N having a stronger effect. N addition also intensifies ammonia nitrification, further reducing pH; P has no significant effect on nitrification. Based on these findings and prior research, we establish two models: one depicting P-driven N availability, the other N-driven P availability. These models highlight carbon-related processes as central to N-P coupling, enhancing nutrient availability in early soils. The results reveal a synergistic pathway where nutrient enrichment boosts co-availability rather than intensifying limitation. This framework clarifies the driving mechanisms of N-P bioavailability interactions that support positive ecosystem succession during soil development.
理解氮磷相互作用对于生态系统中的共同限制至关重要，但由于框架过于简化，目前仍不清楚。在此，一项针对早期土壤的大规模氮磷添加实验揭示了驱动养分耦合的四个关键过程，强调了碳的核心作用。添加氮显著提高了磷的有效性。磷的有效性驱动生物固氮。两种养分都刺激碳固定，其中氮的作用更强。添加氮还会加剧氨硝化作用，进一步降低pH值；磷对硝化作用没有显著影响。基于这些发现和先前的研究，我们建立了两个模型：一个描述磷驱动的氮有效性，另一个描述氮驱动的磷有效性。这些模型突出了与碳相关的过程是氮磷耦合的核心，提高了早期土壤中的养分有效性。结果揭示了一条协同途径，即养分富集促进了共同有效性，而不是加剧限制。该框架阐明了氮磷生物有效性相互作用的驱动机制，这些机制支持土壤发育过程中生态系统的正向演替。
