Early post-fire regeneration of a fire-prone subtropical mixed Yunnan pine forest in Southwest China: Effects of pre-fire vegetation, fire severity and topographic factors

• First post-fire regeneration study of Yunnan pine forests widespread in Southwest China.
• Partition effects of pre-fire vegetation, fire severity, topography on post-fire regeneration.
• Ample summer rainfall stimulated an active post-fire tree regeneration soon after the burning.
• Community, elevation, position, not fire severity dominate regeneration density and composition.
• The forests are resilient to fire via the facultative regeneration strategies of dominant species.

Early stages of post-fire regeneration are sensitive to various factors, and can provide critical information for understanding forest responses to fire disturbance and projecting subsequent forest dynamics. Yunnan pine forests are the most widespread conifer forest type in Southwest China, and are frequently threatened by fire disturbance. Post-fire regeneration of this forest type, however, has not been previously studied. In this study, we investigated the early post-fire regeneration in mixed Yunnan pine forests five months after a severe burn in 2013 on Mt. Qinglongling, Yunnan Province, China. We found very active post-fire regeneration in the burned area likely facilitated by ample summer rainfall, with an average regeneration density of ∼105 stems ha−1. Species composition of the post-fire regeneration was highly similar to the pre-fire community–the similarity between the pre- and post-fire communities was 0.530 ± 0.222. Elevation, pre-fire community type, and slope position were the three primary factors in the variations in regeneration density and species composition, while the impact of fire severity was low. The regeneration density of Pinus species and evergreen broadleaf species showed contrasting patterns across the environmental gradients, and the results implied that Yunnan forests are generally resilient to fire disturbance. The controlling impacts of the pre-fire community on post-fire regeneration are driven by the efficient regenerating strategies of dominant species, and are a comprehensive reflection of habitat conditions, which are primarily mediated by topographic features. Species regeneration strategies and the high resilience of the community to fire disturbance should be taken into account in fire prevention and management approaches for this forest type.