# Climatic Adaptability Changes in Leaf Functional Traits of Old Pinus tabulaeformis in Loess Plateau

## TL;DR

This study explores how old Pinus tabuliformis trees in the Loess Plateau adapt to climate through changes in leaf traits, revealing key strategies for drought resilience.

## Contribution

The study introduces a novel integration of phylogenetic and environmental analyses to understand adaptive strategies in old P. tabuliformis.

## Key findings

- Leaf chemical and physiological traits show significant spatial differentiation, indicating strong environmental plasticity.
- Old trees in Taibai predominantly use the Stress-tolerators strategy (S strategy), with S% = 92.32.
- Environmental factors drive 33.56% of leaf trait diversity, while phylogenetic effects account for only 8.91%.

## Abstract

A systematic examination of leaf functional traits, environmental determinants, and adaptive regulation strategies in old Pinus tabuliformis was conducted in the Loess Plateau region. During the peak growth period (July) of P. tabuliformis in 2023 and 2024, integrating phylogenetic comparative methods with environmental gradient analysis, we quantified 28 functional traits (7 morphological, 8 anatomical, 5 chemical, and 8 physiological traits) of old P. tabuliformis. The result shows significant spatial differentiation in leaf chemical and physiological traits, demonstrating exceptional environmental plasticity. Old trees in the Huanglong area of central China tend to be of the resource acquisition type, while the proportion of the Stress-tolerators strategy (S strategy) is higher in the Taibai (S% = 92.32). The combined effect of environmental factors is the main driving factor for the diversity of leaf functional traits (33.56%), while the independent effect of phylogenetic accounts for only 8.91%. And regression modeling identified several traits, such as Malondialdehyde (MDA), Peroxidase (POD), and Superoxide dismutase (SOD), as sensitive indicators of geographical and climatic adaptation. In conclusion, this study elucidates drought adaptation mechanisms in old P. tabuliformis through leaf functional trait analysis, establishing a scientific framework for conserving old trees in Loess Plateau under climate change.