Different functional responses in populations of Polylepis quadrijuga (Rosaceae) as a consequence of anthropogenic disturbance

The monodominant forests of Polylepis quadrijuga, endemic to the páramos of the eastern cordillera in the Colombian Andes, are among the most threatened in South America due to fragmentation and anthropogenic degradation. Despite their role in regulating water flow and forming biodiverse, endemic biotic communities, there are few studies on their functional responses to stress caused by anthropogenic disturbance and climate change. In this study, we evaluate how six different populations of P. quadrijuga with distinct levels of anthropogenic disturbance (low and high) change 11 foliar, stem, and root functional traits. Also, the physicochemical properties of the soils were analyzed, and mycorrhizal colonization was quantified to evaluate how each population responds to the stress conditions in their vital ecosystem. The results indicated that populations with lower disturbance levels exhibit a conservative leaf trait configuration, whereas those with higher disturbance levels adopt an acquisitive strategy, potentially making them more vulnerable. Additionally, we found no functional coordination between above- and below-ground traits. The results also highlight the colonization by arbuscular mycorrhizal fungi (AMF). It is essential to develop strategies tailored to the specific needs of each population to effectively conserve this important ecosystem.