Marcus Spiegel ’17
Civil and Environmental Engineering
Soils in Africa: Effects of Salinization on Vertisol Patterns in Central Kenya, Kenya
Desiccation cracking in the black cotton soils of Kenya influences both the flow of water into the ground and the drying of the soil. An understanding of these physical processes is integral to our knowledge of the water cycle and Earth-atmosphere greenhouse gas exchange. As a research assistant this summer in the Caylor Lab, I was investigating how biological factors—specifically vegetation, animal compaction, and the presence of termite mounds—influence the depth and extensiveness of these crack networks in the swelling soil. In order to characterize these crack networks, my research group poured resin, a two-part liquid substance that hardens when mixed, into cracks in areas of soil that had been affected by the biological factors we were studying. We excavated the resulting casts and generated digital representations of them using medical magnetic resonance imaging (MRI). Through this research, I gained insight into how different climate and environmental factors can affect land’s physical processes. Furthermore, I learned how to systematically conduct experiments in the field and how to use computer programming to perform image analysis. This project has kindled my interest in a career in which I can spend time conducting research outdoors.
Caylor Lab Princeton University, Princeton, NJ, Kenya
Kelly Caylor, Associate Professor, Civil and Environmental Engineering; Keita DeCarlo, Ph.D. Candidate, Civil and Environmental Engineering