Functional traits of Cynodon dactylon leaves and their influencing factors in different regions of the Henan Province

The functional traits of leaves in response to environmental changes can reflect the adaptive strategies of plants towards their surroundings. Based on the investigation and sampling of 20 sampling points in the Henan Province, which were merged into 5 regions based on soil types, we measured 8 leaf functional traits of Cynodon dactylon leaves. These traits include organic carbon, nitrogen, phosphorus content, leaf dry matter content, specific leaf area, and leaf nutrient stoichiometric ratio. By considering soil nutrients, soil hydrothermal conditions, and climatic factors, we explored the characteristics of leaf functional traits of C. dactylon in different regions of Henan Province as well as their response to influencing factors. The results indicate that: 1) Significant differences in the functional traits of C. dactylon leaves were observed among the different regions of Henan Province. The leaf nutrient and leaf dry matter content of C. dactylon in the Xinyang plain area (0.215 g·kg⁻¹) were significantly higher than those in the Zhumadian (0.045 g·kg⁻¹), Nanyang (0.057 g·kg⁻¹), Xinyang depression (0.093 g·kg⁻¹), and western Henan (0.132 g·kg⁻¹) areas (P < 0.05). 2) The dry matter content of C. dactylon leaves exhibited significant positive correlations with leaf phosphorus content (P < 0.01). Additionally, leaf phosphorus content showed a significant positive correlation with leaf nitrogen content (P < 0.01). 3) Soil phosphorus content, soil moisture, soil pH, and climatic factors (average annual temperature and average annual precipitation) could explain 73.6% of the changes of leaf functional traits with environment, and soil phosphorus content contributed the most. Conclusively, regional variations were observed in the functional traits of C. dactylon leaves across different regions of Henan Province. These variations were primarily influenced by soil nutrient factors.