Ezra's Round Table / Systems Seminar: Jinfeng Liu (Alberta)

Description

Towards Agricultural Water Sustainability through closed-loop Irrigation

The challenge of ensuring water and food security has been consistently recognized as one of the most significant global risks by the World Economic Forum. Agriculture accounts for approximately 70% of the world’s freshwater consumption. However, the average irrigation water use efficiency is low, estimated to be around 50% to 60%. This inefficiency is primarily due to the open-loop nature of the current irrigation strategy, which does not consider real-time field conditions, such as soil moisture when determining the amount and timing of irrigation. From a systems engineering perspective, improving water use efficiency requires closing the decision-support loop and forming a closed-loop system for precision irrigation. This involves using sensors to collect real-time field information, which is then fed back to a control algorithm to calculate the best irrigation commands. Closed-loop irrigation has been shown to bring significant water conservation and economic benefits in greenhouses and nurseries under controlled environments. However, it is unclear whether closed-loop irrigation can achieve the same benefits in large-scale irrigated agriculture, which is subject to significant uncertainties such as weather and sensing conditions.

To implement a closed-loop irrigation system, various sensing instruments such as soil moisture sensors, evapotranspiration gauges, and thermal cameras are used to collect real-time field information on soil moisture, temperature, and other factors. This information is then fused together to estimate the entire field’s conditions, which is fed back to a control system. The control system calculates the best irrigation commands for the next few hours or days based on a field model, estimated field conditions, local weather forecast, and other pre-specified irrigation requirements. However, implementing such a system for large-scale agricultural fields presents significant challenges due to nonlinearities, uncertainties, and the large size of fields. We have been working towards realizing a closed-loop irrigation system for large-scale fields by developing technologies in field modeling, soil moisture estimation, irrigation scheduling, and control. In this talk, I will share our achievements and lessons learned on this journey.
 

Bio:
Dr. Jinfeng Liu is a Professor in the Department of Chemical and Materials Engineering at the University of Alberta. He received his Ph.D. in chemical engineering from the University of California, Los Angeles (UCLA) and his M.Sc. and B.Sc. from Zhejiang University. Dr. Liu’s research interests lie in process systems and control engineering, focusing on developing innovative modeling, estimation, and control methods to tackle the pressing challenges in closed-loop smart agricultural irrigation for water sustainability. Dr. Liu has published 3 books, over 200 journal and conference papers, and edited a few special issues. Dr. Liu currently serves as the editor-in-chief for the IChemE journal Digital Chemical Engineering. He also holds roles as an associate editor for several other journals, including the IFAC Journal of Process Control, Control Engineering Practice, International Journal of Systems Science, and MDPI Journal of Mathematics.