The central goal of my lab is to understand the ecosystem consequences of land-use change in the tropics. My group studies how vegetation and soils respond to land-use change, focusing on feedbacks between vegetation dynamics and nutrient dynamics in (mostly) secondary tropical forests. In Mexico, Costa Rica, and Indonesia, we work at various spatial scales (within stands, across stands, across landscapes) to investigate relationships between the structure of the tree community and nutrient cycling. We explore the effects of disturbance type, disturbance intensity, and time since the last disturbance, spanning years to decades of forest change following shifting cultivation, pasture, and cash crops such as chile, rubber, or fruits. Given the trajectory of continued disturbance in tropical forests, we recognize the importance of studying more than one cycle of disturbance and recovery. Using novel approaches and collaboration with social scientists to determine patch histories, we investigate forest dynamics over periods from decades to centuries. In Indonesia and Mexico, we have shown that forest response to anthropogenic disturbance is contingent on the number of prior disturbance cycles, with important consequences for how we model and manage future forest development. My work in the dry forests of the Yucatan has influenced the direction of my research in the rainforests of Costa Rica. We are exploring interactions between water stress and nutrient cycling along a gradient from dry to very wet forests, trying to determine whether climate effects differ in mature and secondary forests.

In the tropics, the impact of disturbance on biodiversity, watershed management, and global carbon cycling are both immediate and great. The work in my lab contributes to understanding the biogeochemical and ecosystem-level processes controlling those responses.