CAM Photosynthesis, Life History and Nitrogen Cycling in the Diverse Neotropical Bromeliads

Brad Oberle

Nitrogen is a critically important nutrient for plant growth. However, current understanding of how nitrogen availability influences plant form and function are based on plants with similar growth forms and means of photosynthesis. Tropical epiphytes, which grow on other plants and obtain water and nutrients from the canopy rather than soil, are very diverse but have been excluded from studies connecting nitrogen use to photosynthesis, growth and ecology. This project will investigate the tropical bromeliads (Bromeliaceae, 3500+ species), a family with many epiphytes and different means of photosynthesis, as a model for understanding how nitrogen scarcity influences physiology, growth and nitrogen cycling through ecosystems. Broadly, this work will use experiments and surveys to test how nitrogen availability influences how plants photosynthesize, invest in leaves versus flowers, and decompose in different habitats. Including tropical epiphytes will provide a more robust framework for understanding the evolution of plant diversity. The project will engage researchers from high school onward in an interdisciplinary team spanning botanical gardens, a liberal arts college and a research university to train a new generation of scientists in collaborative, greenhouse-based research, with conservation applications in Florida where many threatened bromeliads grow.