Developmental plasticity drives converge nt shifts in phosphorus acquisition strategies towards root phosphatase activity in Moso bamboo under nitrogen addition

Abstract Anthropogenic nitrogen (N) deposition is a major driver of global change. However, its effects on the developmental plasticity of plant nutrient strategies remain poorly understood. This is particularly critical in phosphorus (P)‐limited subtropical forests, where N‐induced shifts in biogeochemical cycles may intensify P constraints. Using Moso bamboo ( Phyllostachys edulis ) as a model system, we investigated the response of root P acquisition strategies and leaf P fractions to different N addition (0, 30 and 60 kg N ha −1 year −1 ) at different developmental stages (young vs. mature). We identified a convergent shift in P acquisition pathways in response to N addition. Young bamboos transitioned from morphological strategies (specific root length and area) to exudation‐based strategies, whereas mature bamboos shifted from carboxylate‐dominated to phosphatase‐enhanced pathways. Ultimately, both stages converged on root phosphatase‐mediated organic P mobilization. This strategic unification was also observed in the leaves. N addition significantly reduced leaf inorganic P pools without altering lipid‐P, residual‐P and nucleic‐P, indicating a prioritization of P for growth under intensified limitation. Key drivers, including soil acidification, depletion of available P, accumulation of microbial biomass P, and increased root phosphatase activity, collectively influenced this root–leaf recalibration. Furthermore, responses in root P acquisition strategies and leaf P fractions saturated at the low N addition level, indicating a non‐linear threshold effect rather than a proportional dose–response. By integrating specific root pathways and internal P fraction dynamics, our study advances the conventional ‘Get–Save–Return’ framework and underscores developmental plasticity as a central mechanism in clonal plant responses to N deposition. These findings provide a new mechanistic insight into nutrient cycling in subtropical forests under global climate change. Read the free Plain Language Summary for this article on the Journal blog.