Institute at Brown for Environment and Society

Gaps in the canopies of tropical rainforests present interesting ecological dynamics by altering light levels, soil humidity, and a number of other biotic and abiotic factors. These temporary gaps, often created by disturbances such as storms, contribute to the heterogeneity of tropical rainforests, and understanding nutrient cycling in these gaps is crucial to understanding the biogeochemical dynamics of a forest as a whole.

My project, advised by Dr. Stephen Porder, is part of a larger manipulated field experiment being conducted by IBES PhD. candidate Lindsay McCulloch. I will examine mycorrhizal fungi (a symbiont of most vascular plant species that exchanges soil nutrients for plant-produced carbon) under different light and soil-nutrient conditions. Light may be a limiting factor in this exchange, as light limits how much carbon a plant can fix through photosynthesis and invest in nutrient-acquiring symbioses.

Understanding if, how, and to what degree light affects this relationship may have implications for our understanding of the carbon and phosphorus cycles in tropical canopy gaps, and observing if/how this relationship interacts with other symbioses, such as symbiotic nitrogen fixation, could enhance our understanding of nutrient cycling more generally.