Pinus yunnanensis var. pygmaea individuals are more ready to embrace wildfire in more fire‐prone areas

Plant functional traits play critical roles in responding to environmental heterogeneity and provide a theoretical basis for understanding species' adaptive strategies. Pinus yunnanensis var. pygmaea , a highly resilient species endemic to the fire‐prone regions of southwestern China, exhibits significant intraspecific variation in numerous functional traits, including serotiny. However, how these functional traits evolved to form an adaptive strategy in response to heterogeneous fire regimes has not been fully explored.

We investigated intraspecific variation in 25 functional traits across 14 P. yunnanensis var. pygmaea populations. The functional traits significantly associated with serotiny were identified, and a fire‐embracing index was developed based on the trade‐offs among them. Subsequently, the environmental factors potentially driving variation in the fire‐embracing index were explored.

Populations with higher serotiny levels exhibited a more pronounced fire‐embracing strategy, characterized by lower leaf nitrogen concentrations, a shorter stature and higher cone crude fat content. These populations tended to occur in areas characterized by larger burned areas and more nutrient‐poor soils.

Our results revealed clear trade‐offs between serotiny and other functional traits of P. yunnanensis var. pygmaea and provided new insights into the evolutionary mechanisms of its fire‐embracing strategy. These findings helped clarify how plants develop adaptive strategies in fire‐prone ecosystems.