Format: ORAL

Maribel Arenas-Navarro1,2, Ken Oyama3, Fernando Pineda-Garca3, Andrs Torres-Miranda3, Horacio Paz1, Felipe Garca Oliva1

1 Instituto de Investigaciones en Ecosistemas y Sustentabilidad (IIES), Universidad Nacional Autónoma de México (UNAM), Michoacán, México. 2 Facultad de Estudios Superiores Iztacala (FESI), Universidad Nacional Autónoma de México (UNAM), México, México. 3 Escuela Nacional de Estudios Superiores (ENES) Unidad Morelia, Universidad Nacional Autónoma de México (UNAM), Michoacán, México.

Ecological stoichiometry analyzes how the balance of multiple elements, such as carbon (C), nitrogen (N), and phosphorus (P), can be used to estimate the ecological strategies of organisms and, in turn, the role they play in the structure and function of ecosystems. Forest ecosystems rely on the emergence and establishment of tree seedlings. At the seedling stage, the ability of plants to compensate for survive, and succeed is critical. Success in the first phase of ontogeny depends on the development of their own resource-acquiring organs, and how well they respond to the environment. This study assessed interspecific variation in functional and stoichiometric traits in seedlings of six oak species from Mexico's tropical dry and temperate forests, corresponding to tropical and temperate environmental groups, respectively. Under controlled conditions, we examined the functional trade-offs and coordination between leaves, stems, and roots that drive differentiation in the ecological strategies of each species. We also analyzed the stoichiometric ratios to understand if the intraspecific variations reflect adaptations of their native climates. Subsequently, we quantified the overlap of functional space with the functional and stoichiometric traits of the species and environmental group levels. Our results showed that oak species from tropical environments allocated more biomass to roots, possibly to obtain water and nutrients to adapt to seasonal drought. Meanwhile, temperate species allocated more biomass to leaves, with higher concentrations of N and P to adjust to light availability and showed more water content in the stem. Finally, we found significant segregation of functional space between species from the same environmental group. Our results highlight the differences in functional traits and element concentrations between species in the same genera, which promote the separation of biogeochemical niches in coexisting species.