PS 89-189 - Does precipitation drive community phenological patterns in tropical dry forest trees? An inter-site comparison says not necessarily

Friday, August 16, 2019
Exhibit Hall, Kentucky International Convention Center
Luna-Nieves Adriana L.1, Jorge A. Meave1, Guillermo Ibarra-Manríquez Sr.2, Edgar Gonzalez1 and Jorge Cortés-Flores Sr.3, (1)Ecología y Recursos Naturales, Universidad Nacional Autonoma de Mexico, Cuidad de México, DF, Mexico, (2)Instituto de Investigaciones en Ecosistemas y Sustentabilidad, Universidad Nacional Autónoma de México, Morelia, Mexico, (3)Laboratorio Nacional de Análisis y Síntesis Ecológica, Universidad Nacional Autonoma de Mexico, Morelia, Mexico
Background/Question/Methods

As water availability is the limiting factor for plant physiology in strongly seasonal ecosystems, changes in precipitation patterns are assumed to have strong influences on phenological patterns. To test this hypothesis, in this study we compared intraspecific variation in leaf, flower and fruit phenology of two populations of ten tree species located in distant geographic locations of the Mexican Tropical Dry Forest whose dry seasons vary in duration and intensity. We conducted monthly observations to evaluate the proportion of the canopy in each phenophase of 200 marked trees (10 tress per species), from March 2012 to February 2013, at two sites: Churumuco, Michoacán, and Nizanda, Oaxaca. We compare the intensity, duration, seasonality and synchrony of each species, and we related those phenological attributes to precipitation.

Results/Conclusions

In spite of environmental differences, phenophases of all the species did not differ significantly among the two sites analyzed. Foliation patterns were almost identical in both populations. Although in reproductive phenophases the intraspecific variation was greater, mainly due to the differences among individuals within populations, considerable synchrony was observed. These results suggest that phenological patterns are constrained not just for precipitation patterns but also for adaptive selective pressures and phylogenetic membership. Future studies should incorporate phylogenetic analyses in similar habitats but different regions to further test the results of this study.