LTREB Renewal: Woody seedling dynamics, climate, and species coexistence in a wet tropical forest

Michigan State University, East Lansing MI

Investigators

Abstract

Understanding the factors that govern the abundance and number of tree species in species-diverse wet tropical forests remains a major challenge in ecology. Complicating this challenge is the knowledge that tropical forests are expected to change as they become warmer and as rainfall patterns change. This long-term study of tropical forest biodiversity tackles this challenge by focusing on the important phases of a tree's life, including seed and seedling production by mature trees, the growth and survival of those seedlings, and the growth and survival of mature trees. The project extends a 13-year record of seedling and mature tree surveys in five forest stands in Costa Rica, with the goal of developing models of critical aspects of forest regeneration - seedling production, dispersal, growth, and survival - in response to light, soil nutrients, rainfall, and temperature. Tree life cycles are typically long, some species reproduce only once every 12 or more years, and many trees live for hundreds of years. The longer-term data collected as part of this study are therefore essential to capture a greater part of the tree life cycle and to span variation in weather conditions. The data and models resulting from the study will identify major mechanisms of species co-existence, helping to explain the unusually high diversity in tropical forests. Improved understanding of the factors that govern the abundance of tree species will aid in predicting forest responses to environmental changes, which is critical to timber production, wildlife habitat, and forest carbon storage. Results will also improve predictions of how some of the most diverse communities on the plant respond to warmer temperatures, reduced rainfall and increasing deposition of chemical pollutants. The project will educate and train students, make valuable long-term data publicly available, and promote science education of the general public through activities at Science Festivals and a website.