Synergistic effects of nitrogen deposition and phosphorus distribution patterns on root morphological and chemical traits, and nutrient efficiency in Chinese fir

作者：Yajing Zhang, Yu Si, Shaoqing Ju, Wanying Jiang, Mingzhen Zhao, Jing Liu, Mulualem Tigabu, Xiangqing Ma, Ming Li · 发表于：Journal of Plant Ecology · 年份：2025 · DOI：10.1093/jpe/rtaf062 · 被引用次数：7 · 研究领域：Soil Carbon and Nitrogen Dynamics、Agronomic Practices and Intercropping Systems、Polymer-Based Agricultural Enhancements

Abstract Increasing nitrogen (N) deposition exacerbates phosphorus (P) limitations in subtropical Chinese fir plantations, yet clonal mechanisms mediating root adaptation to heterogeneous P environments remain unclear. This study investigates the growth and metabolic responses of three clones (Y061/Y020: P-efficient; Y2C: P-sensitive) under N deposition and contrasting P distributions. Elevated N deposition enhanced aboveground and belowground biomass under heterogeneous P conditions, particularly enhancing Y061’s root length and surface area. Elevated N deposition significantly increased APase activity while decreasing organic acid secretion, particularly under homogeneous P-deficient conditions. Heterogeneous P supply amplified clonal divergence: P-efficient clones exhibited higher phosphorus absorption efficiency (PAE) than Y2C through root morphological plasticity, while N deposition upregulated APase activity but reduced total organic acids secretion. Metabolomic revealed N-driven shifts in exudate profiles, with lactic, malonic, succinic and oxalic acid increasing while shikimic, quinic and malic acids decreased. Notably, nitrogen absorption efficiency synergistically enhanced PAE under high N conditions. Clones Y061 and Y020 demonstrated superior N and P absorption capabilities, while clone Y2C prioritized enzymatic P mobilization in homogeneous deficiency but showed compromised growth. We demonstrate that N deposition restructures root foraging strategies along a “mor...