Phenotypic Variation of Oak Species (Quercus spp.) Reveals Adaptive Strategies Across Natural and Semi‐Artificial Oak Stands

TL;DR

This study explores how oak species adapt to different environments by analyzing leaf traits, revealing that some species are more flexible in changing conditions.

Contribution

The study reveals how hybridization and genetic coadaptation influence developmental stability and adaptive strategies in oak species.

Findings

Cerris group oaks show stable leaf morphology and higher fluctuating asymmetry in stable environments.

Q. fabri exhibits higher phenotypic plasticity and lower asymmetry, adapting better to dynamic environments.

Hybridization in Q. fabri increases morphological variability, affecting developmental stability.

Abstract

This study investigated leaf phenotypic variation in oak species to better understand how different groups of oaks adapt to diverse environmental conditions. We examined the leaf phenotypic traits of six oak populations in two mixed forests with differing species compositions: Zijin Mountain in Jiangsu Province, composed of
Quercus acutissima
,
Q. variabilis
, and Q. fabri; and Youhua Village in Anhui Province, consisting of
Q. acutissima
,
Q. chenii
, and Q. fabri. The results indicated that species in the Cerris group (
Q. acutissima
,
Q. chenii, and
Q. variabilis
) exhibited stable leaf morphology and higher fluctuating asymmetry (FA), suggesting adaptation to stable environments. In contrast, Q. fabri from the Quercus group showed higher phenotypic plasticity and lower FA, indicating a strategy for adapting to dynamic environments. The study also explored the relationship between FA and phenotypic plasticity, revealing that while both traits are influenced by environmental stress, phenotypic plasticity allowed for more flexible responses to environmental change. Additionally, our research highlighted the role of hybridization and genetic coadaptation in influencing developmental stability, with higher hybridization rates in Q. fabri leading to greater morphological variability. These findings underscore the importance of environmental factors, genetic variation, and hybridization in shaping the adaptive strategies and phenotypic traits of oak species, providing valuable insights into the complexities of adaptation and species identification.

Our findings highlight the significant impact of forest management on morphological traits, particularly the differences observed between the semi‐artificial forest at Zijin Mountain and the natural forest at Youhua Village. The study underscores the influence of both biotic and abiotic factors on phenotypic traits, with notable implications for forest management and conservation strategies. The observed relationship between FA and hybridization potential, especially in the context of the more variable natural forest environment, offers new insights into the adaptive strategies of oak species.

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