Abstract

Dryland regions of the southwestern United States are rapidly warming, and rainfall is becoming less frequent and more intense, with major yet poorly understood implications for ecosystem structure/function. Thermography-based estimates of canopy temperature can be used to infer changes in gross primary productivity (GPP), and evapotranspiration (ET). In the Ecosystem Climate Dynamics (ECD) lab at the University of Arizona, we utilize novel applications of high spatiotemporal thermography implemented at the plot to ecosystem level to evaluate its potential to track key plant hydraulic traits. We leveraged two long-term experiments: 1) The Rainfall Manipulation experiment at the Santa Rita Experimental Range in Southern Arizona (RainManSR), which includes treatments designed to test the impacts of temporal repackaging of a fixed total seasonal precipitation amount on key plant function groups of the Sonoran desert; and 2) A long-term climate manipulation experiment designed to evaluate the sensitivity of key plant and soil functional groups of the Colorado Plateau, including biocrusts in Southern Utah. We also leveraged two active thermal infrared cameras on eddy covariance flux towers in a semiarid mixed conifer forest site and a grassland site in Arizona. Overall, our cross-site findings imply shifts in climate, including a change in the timing of precipitation, will have major implications for dryland community composition and function.

Biography

Mostafa Javadian is a postdoctoral research associate in the Ecosystem Climate Dynamics lab in the School of Natural Resources and the Environment at the University of Arizona. Mostafa does research in remote sensing of drylands, with an emphasis on detecting vegetation water stress using thermal remote sensing from tower, drone, and satellite platforms. Mostafa earned his undergraduate in civil engineering, wherein an environmental course he discovered that he might be able to combine his love of the environment into a viable career. He went on to earn a Master’s degree in water resources management and engineering from the Sharif University of Technology in Tehran, Iran with a focus on estimating agricultural water consumption using satellite remote sensing observations. Then, he moved to the United States in 2019 and he earned his Ph.D. in hydrology and remote sensing from the University of Arizona in May 2022 with a focus on vegetation water stress.

Venue

Room: 
In-person: Global Change Institute - 275. This seminar will be held using the video conferencing software Zoom.