Data from: leaf functional diversity and environmental filtering in a tropical dry forest: comparison between two geological substrates

The role of geological substrate in shaping plant community functional
diversity remains poorly understood. Considering the involvement of leaves
in the energy, water and nutrient economics of plants, we hypothesized
that leaves experience geology-related filtering, impacting functional
attributes and functional leaf community diversity on different
substrates. We studied tropical dry forest communities on limestone and
siliciclastic phyllite-derived soils, comparing their functional diversity
and soil physico-chemical properties. We predicted the most benign habitat
(less severe filter) to be associated with higher leaf functional
diversity and an acquisitive strategy prevalence, while the more stressful
habitat should show conservative leaf traits and lower leaf functional
diversity. We measured six traits in 31 common tree species (representing
~80% of community crown cover): leaf area, specific leaf area, leaf
thickness, leaf dry matter content, petiole length, and leaf blade
narrowness. Leaf functional diversity was assessed through the functional
trait dispersion metric. Intraspecific functional variation was examined
in 25 species shared between substrates. The limestone substrate was more
fertile (higher phosphorous) with higher water retention, while phyllite
had higher nitrogen and lower humidity. Principal component analysis
segregated plots by substrate, with limestone plots being more clustered.
Community leaf functional diversity was higher in the limestone forest.
Most species examined showed inter-substrate trait differences in at least
one leaf functional trait. The two substrates constituted distinct growth
environments, with the more benign substrate associated to higher
community functional leaf diversity. The intraspecific analysis revealed
the prevalence of acquisitive traits in the more benign and more
conservative traits in the more stressful habitat. This study advances our
understanding of the role of geological substrate as an environmental
filter in tropical dry forest, influencing leaf functional responses and
emphasizing the importance of intraspecific functional variation.