After witnessing tropical deforestation in Honduras and collaborating with farmers impacted by the degradation in these forests, Ph.D. candidate Rachel Ward knew what she wanted to study next–tropical forest regeneration. Ward’s passion to study the impact of tropical forests on both communities and the global carbon cycle led her to pursuing a Ph.D. with the NGEE-Tropics team. Equipped with a social science Master’s degree, she is now studying forest regeneration and how this relates to carbon dynamics.
Ward collecting litterfall on the Barro Colorado Island in Panama.
What led you to studying regeneration rates of tropical forests?
I lived in Honduras after college, and then did a Master’s program at UC Berkeley in Latin American studies. For my Master’s thesis, I returned to Honduras because of my interest in agroforestry, specifically coffee systems.
Coffee farmers were (and still are) dealing with a fungal disease called coffee rust that attacks the leaves of coffee plants. Because farmers lacked the resources to control this disease, they would literally abandon their coffee fields and cut down forests elsewhere to create new ones. They recognized all of the problems deforestation causes at the landscape scale, but didn’t see another option. Especially in light of climate change and how important the tropics are to the global carbon budget, the forest part of that was really interesting to me. It really pushed me back into grad school – and led me to drinking a lot of coffee!
A leaf experiencing coffee rust-a fungal disease affecting the leaves of coffee plants.
How are tree regeneration rates related to or influenced by climate change?
Forest regeneration is a key demographic rate, along with growth and mortality, that we need to understand in order to predict how forest structure and composition will be influenced by climate change. We expect that climate change will bring increasingly frequent and intense disturbances, like hurricanes, droughts, and fires. The rate of regeneration and types of species able to regenerate after disturbances will have a huge impact on future forests. On top of that, the tropics cycle more carbon, energy, and water than any other biome – which means that small changes in these demographic rates can have large consequences for the global carbon budget.
Has your Ph.D. thus far exposed you to new experiences or skills?
When I came back to school I knew I wanted to build quantitative skills, but I don’t think I ever envisioned my PhD would focus so much on modeling! NGEE-Tropics has been really motivating in terms of building computational skills, and I love that the community allows you to learn from so many people’s expertise. I’ve been learning how to run FATES, and I’m working on a project I hope will help improve the way FATES represents regeneration. It’s a steep learning curve, and I’ve had to put in a lot of time and effort, but it’s really rewarding.
Coffee farm in Honduras. Photo courtesy of Rachel Ward.
Has there been an experience that reinforced your scientific passion?
Visiting field sites has been really eye-opening. It’s humbling – how can we even pretend to model these super complex systems? When I visited the old growth forest at the NGEE-Tropics research site at Barro Colorado Island in Panama, I was in awe of the diversity, not just of the tree species, but everything – lianas, frogs, ants, fungi…there’s just so much going on. Being immersed in the ecosystem emphasizes how irreplaceable it is and how important it is to understand our forests so that we can protect all of the life they support.
Are you exploring ways to integrate your social science background into your Ph.D.?
Working with coffee farmers and agroforestry definitely motivated my interest in tropical forest vegetation dynamics, and I think it’s one of the reasons it’s been so interesting and rewarding to work on this project. I’m not sure yet whether the project on the social dimension of forest restoration will be one of my chapters, but it’s something I’m thinking about.