Plant functional traits in 42 paramo species in Colombia

Páramos are exceptionally species-rich tropical alpine ecosystems that
provide several important ecosystem services, including carbon storage and
water provision. The responses of páramo plant species
to climatic change are largely unknown, but classifying
species by functional type and ecological strategy can help reduce
complexity for modeling and conservation efforts. We measured 22 traits in
42 plant species with various growth forms in the Colombian Andes. We
classified plant ecological strategies using CSR (C: competitor, S: stress
tolerator, R: ruderal) analysis and identified plant functional types
(PFTs) using hierarchical clustering of principal components.
Additionally, we calculated the functional originality of each species to
identify species with unique trait combinations. We identified a high
degree of convergence among traits and strategies, with most species
characterized by the S and SC strategies. Considering the full
set of traits, only three PFTs were identified: one composed of forbs and
shrubs with tender leaves (PFT1), another composed only of species with
rosettes form (PFT2), and a third composed of shrubs with tough leaves
(PFT3). Values of functional originality were generally low, suggesting
high redundancy in plant traits. PFT2 species, mostly
rosettes, exhibited the highest functional originality of all the
groups. Our results imply the existence of a limited set
of ecophysiological strategies in the páramos,
likely driven by the extremely stressful conditions in these systems. This
functional redundancy may indicate heightened vulnerability to
environmental changes; however, the presence of multiple species with
shared functional traits could provide some resilience to
disturbance.