Dissertation Research: Tropical Tree Fruiting Phenology and Patterns of Seed Dispersal and Seedling Establishment

Utah State University, Logan UT

Investigators

Abstract

Schupp 0072872 Tropical forests may remain species-rich due to the limited regenerative capacity of individual species. If, in general, tree seeds establish sparsely, or in locations unsuitable for long-term growth, such limited regeneration precludes individual species dominance. Studies of seed dispersal and survival patterns can identify factors that limit tree regeneration. In particular, this project will experimentally test how seed density and desirability affect seed eating by rodents. Most tropical tree seeds are dispersed in varying densities by animals, and seeds of different species differ strongly in desirability. Marked seeds of a test species will be placed in different densities and in seed mixes of two species differing in desirability. To determine the effect of density and desirability on seed fate, these marked seeds will be censused over time and compared to seeds protected from rodents. This project will contribute to an ecological understanding of seed plant diversity in general by testing a broad hypothesis in a diverse plant community. Results will help determine if limited individual regenerative capacities can explain the maintenance of species diversity in a variety of ecosystems. In addition, investigations of seed mortality can be applied to managing composition of tree species in remnant as well as natural forests.