CEE Seminar: Plant Roots - The Other Leaky Pipe Network Beneath our Feet

Engineering Lecture Hall (ELH) 110
Teamrat Ghezzehei, Ph.D.

Associate Professor
School of Natural Sciences
UC Merced

Abstract: Essential soil-derived resources of terrestrial plants, including water and nutrients, are often scarce and patchy. Therefore, plants often rely on evolutionary adaptive traits that allow them to optimally exploit these scare resources. One such trait is the leakiness of the root network, which allows plants to transfer water between wet and dry patches of the soil system. This phenomenon is commonly referred to as hydraulic lift or hydraulic redistribution. The bulk of hydraulic lift research has been driven by ecology of natural vegetation, and it has been observed in several semi-arid environments worldwide. Whether hydraulic lift is an unavoidable accident that plants have learned to exploit or a biologically controlled mechanism has not been fully answered yet. This presentation will explore the biotic and abiotic prerequisites for hydraulic lift and how roots engineer their immediate environment to enable this phenomenon. Finally, we will discuss examples of how plants' ability to perform hydraulic conductivity can be leveraged in both subsistence and intensive agricultural practices for boosting sustainability of food production systems.

Bio: Teamrat Ghezzehei’s research interest broadly covers movement and transformation of mass and energy in porous media across scales and interfaces, with focus on evolution of soil physical characteristics by biogenic (e.g., plant roots) and abiogenic (e.g., wetting-drying and low-intensity burns) means. His recent studies include transformations of rhizosphere soil that benefit water and nutrient uptake efficiencies in resource limited environments. His research approach integrates laboratory and field observations with mathematical modeling and computer simulations. He is currently an associate professor of environmental soil physics in the Department of Life and Environmental Sciences at UC Merced. Ghezzehei was a postdoctoral fellow (2001-2004) and geological scientist (2004-2008) at the Earth Sciences Division, Lawrence Berkeley National Lab. Prior to that Ghezzehei earned a doctorate in soil science from Utah State University and bachelor's degree in soil and water conservation from University of Asmara, Eritrea.