When I first began my undergraduate degree at The University of Georgia I was majoring in Ecology and working on a research project in a lab that focused on the movement of carbon through ecosystems in the context of climate change. Although I eventually shifted to a minor in Ecology and majored in Environmental Economics and Management, I remained interested in natural processes that emitted or sequestered carbon dioxide. The Graduate Certificate in Sustainability gave me the chance to return to this earlier interest through Ecosystem Ecology, a course taught by Dr. Nina Wurzburger in the Odum School of Ecology (In my undergraduate research I worked in the Wurzburger research group on various projects related to the carbon cycle through ecosystems under stressors like heat and fire). This course focused on energetic and biochemical cycles and their interplay with the structure of ecosystems on local to global scales.

Ecosystem ecology gave me an advanced knowledge of how elements and molecules move through ecosystems and connect the world. The material was a fascinating marriage of the atomic and global scales, and hugely broadened my understanding of the connectivity of the world’s systems. I was especially interested in the chemical composition of soils and ocean water, because these are the two largest carbon sinks on our planet. We covered this material at a molecular level- drawing and understanding how the structure of soil and marine molecules made them more or less open to bonding with other molecules- like carbon dioxide. In particular, we discussed how different regions of the world tend to have chemically different soil and ocean water compositions that can either enhance or inhibit plant growth and carbon sequestration. Gaining this mico-level knowledge helped me to truly understand the movement of key elements such as carbon and phosphorus in our biosphere.

This course was also special for me because I worked with my now-husband on our first collaborative project. In this project, we attempted to use machine learning to predict carbon emissions from soils under differing levels of temperature increase (to model climate change) based on a novel variable: the dominance of either arbuscular- or ecto-mycorrhizal fungi (these are fungi that live in soil in/around tree roots). The dataset that we use for this project was one that I had created the previous summer as part of my fieldwork with the University of Georgia Odum School of Ecology in the Wurzburger research group. Ultimately, we were able to produce models that predicted intervals of temperature sensitivity of carbon loss from soils with accuracies, scored by percentage of correctly identified classes, ranging from 0.77 to 0.95 and which utilized mycorrhizal fungal dominance, Soil % Nitrogen, Carbon, and Water, and location information. From this project we have gone on to work together on several other sustainability initiatives, a field about which we are both passionate.

Overall, the biggest take-away from this course was connectivity, and the need for systems thinking. We covered some of the methods that humans have used in an attempt to promote carbon sequestration, like iron fertilization of oceans. Inevitably, these methods have far-reaching undesirable impacts because of the way that changes in the chemical makeup of an ecosystem cascade out across an infinite number of connected systems. I learned the importance of mapping out and considering impact pathways- both at  micro and macro scales, and this is a skill that I have carried through to my work as a sustainability professional.