Assessing Different Plant-Centric Water Stress Metrics for Irrigation Efficacy Using Soil-Plant-Atmosphere-Continuum Simulation

Authors

Jingwen Zhang, University of Illinois at Urbana ChampaignFollow
Kaiyu Guan, University of Illinois at Urbana-ChampaignFollow
Bin Peng, University of Illinois at Urbana ChampaignFollow
Ming Pan, Princeton UniversityFollow
Wang Zhou, University of Illinois at Urbana ChampaignFollow
Robert F. Grant, University of AlbertaFollow
Trenton E. Franz, University of Nebraska-LincolnFollow
Daran Rudnick, University of Nebraska - LincolnFollow
Derek M. Heeren, University of Nebraska-LincolnFollow
Andrew Suyker, University of Nebraska - LincolnFollow
Yi Yang, University of Illinois at Urbana ChampaignFollow
Genghong Wu, University of Illinois at Urbana ChampaignFollow

ORCID IDs

Jingwen Zhang https://orcid.org/0000-0002-3264-3014

Bin Peng https://orcid.org/0000-0002-7284-3010

Robert F. Grant https://orcid.org/0000-0003-2947-0906

Trenton E. Franz https://orcid.org/0000-0003-2947-0906

Yi Yang https://orcid.org/0000-0002-4736-5491

Genghong Wu https://orcid.org/0000-0002-6227-6390

Document Type

Article

Date of this Version

2021

Citation

Zhang, J., Guan, K., Peng, B., Pan, M., Zhou, W., Grant, R. F., et al. (2021). Assessing different plant-centric water stress metrics for irrigation efficacy using soil-plant-atmosphere-continuum simulation. Water Resources Research, 57, e2021WR030211. https://doi. org/10.1029/2021WR030211

Comments

© 2021. American Geophysical Union. Used by permission.

Abstract

Understanding plant water stress (PWS) in the soil-plant-atmosphere-continuum (SPAC) that connects water supply from soil, water demand from atmosphere, and plant self-regulation is a prerequisite for efficient irrigation in response to water scarcity. Currently, PWS can be defined in various ways, for example, based on environmental factors and/or plant-centric metrics. The environment-based metrics usually do not take plants into consideration. Regarding the existing plant-centric metrics, their interconnections and abilities to capture the physical water constraints from both soil water supply and atmospheric water demand are still unclear. This research investigates the theoretical foundations behind different PWS metrics, and assesses their efficacy and potentials for irrigation scheduling. This study first investigated the interconnections among different PWS metrics and the co-regulation of soil moisture and vapor pressure deficit (VPD) on the plant-centric metrics through an advanced process-based model, ecosys. We then use ecosys to test different PWS metrics’ performance in guiding irrigation in terms of water use, maize yield, and economic profits. The case study was conducted at sites across a dramatic rainfall gradient in Nebraska, the largest irrigation state in the United States Corn Belt. The ecosys simulation indicates that canopy water potential and stomatal conductance (gs) are the most effective plant-centric metrics in the SPAC system in indicating PWS. In addition, our findings show that using the plant-centric metrics-based irrigation schemes, which capture the co-regulation of soil moisture and VPD, can improve producers’ economic profits through water savings.