Objective The study aimed to explore the impact of geographical differentiation on the stoichiometric characteristics of Pleioblastus amarus leaves and identify their primary environmental drivers.

Method The C, N, P content, and stoichiometric ratio of P. amarus leaves from three different regions: Qianshan County, Anhui Province; Longyou County, Zhejiang Province; and Shaxian District, Fujian Province were explored. Pearson correlation analysis, LSD difference analysis, and structural equation modeling were employed to investigate the correlation between these characteristics and environmental factors.

Result The results indicated that the contents of C, N, and P in P. amarus leaves decreased with increasing latitude, while the ratios of C∶N, C∶P, and N∶P showed an overall upward trend. Notably, P. amarus leaves from Qianshan County exhibited significantly lower concentrations of C, N, and P than those from Longyou County and Shaxian District. Moreover, the ratios of C∶N, C∶P, and N∶P were significantly smaller in Qianshan County than those in the other two regions. Additionally, the study found that as the age of the culms increased, the concentrations of C, N, and P decreased, while the ratios of C∶N and C∶P increased. There was no significant change observed in the N to P ratio with different ages. Pearson correlation analysis revealed that the annual mean temperature and soil chemical properties (such as total nitrogen, total phosphorus, total potassium, hydrolyzed nitrogen, available phosphorus, available potassium, organic matter, etc. ) significantly influenced the stoichiometric characteristics of P. amarus leaves. On the other hand, mean annual precipitation and soil physical properties had little effect on the stoichiometric characteristics of P. amarus leaves. The results of the structural equation model indicated a significant positive correlation between climatic factors, soil factors, and leaf stoichiometry characteristics, with similar effects.

Conclusion This suggests that the variation in leaf stoichiometry due to geographical differentiation may be attributed to the combined effect of climate and soil factors. Among these factors, the annual average temperature, soil hydrolyzable nitrogen, soil total phosphorus, and soil available potassium are the main indicators affecting the stoichiometric variation of leaves.