Water Use by Irrigated Turfgrass and Connections to Climate and Biophysical Processes

Author

Karem Meza, Utah State UniversityFollow

Date of Award:

5-2025

Document Type:

Dissertation

Degree Name:

Doctor of Philosophy (PhD)

Department:

Civil and Environmental Engineering

Committee Chair(s)

Alfonso F. Torres-Rua (Committee Chair), Lawrence Hipps (Committee Co-Chair)

Committee

Alfonso F. Torres-Rua

Committee

Lawrence Hipps

Committee

Kelly Kopp

Committee

Mac McKee

Committee

Burdette Barker

Abstract

Urbanization and limited water supply and storage result in imbalanced urban water budgets. Quantification of water use becomes important in urban landscapes because urban turfgrass requires a significant amount of water and competes with other urban requirements. Evapotranspiration (ET) plays a crucial role in determining irrigation needs. Credible measurements and spatial estimates of urban turfgrass ET are needed for urban water management. However, these have not been addressed in urban landscapes in arid and semiarid regions. Despite estimating spatial urban turfgrass ET, turfgrass quality linked to ET has not been widely evaluated. Due to different environmental conditions, the driving forces for ET responses are unclear. The objective of this research is to estimate high-resolution spatial urban turfgrass ET and turfgrass quality and quantify the connections between atmospheric and biophysical factors that govern urban turfgrass ET. To accomplish this, EC measurements of hourly and daily actual ET over irrigated turfgrass were used to validate the remote-sensing ET model. Ground truth turfgrass quality was used to evaluate the remote sensing TQ model. EC and weather data were used to examine the ET response to variations in climate and physiological factors. Results showed significant variabilities of ET_a related to atmospheric conditions and soil water availability. The average daily turfgrass ET_a for the peak summer season was 5.9, 5.0, and 5.1 mm day^-1 in 2021, 2022, and 2023. The TSEB-PT model and TQ – RF using sUAS imagery showed the ability to estimate the spatial variation of daily ET_a and TQ for a large urban turfgrass surface, which is useful for landscape precision irrigation management for acceptable turfgrass under drought conditions. In addition, ET (latent heat flux) spatial maps of urban turfgrass may be useful in determining large-scale energy balances in urban environments. ET responds to atmospheric and biophysical factors under various climate and soil water conditions, which is critical to developing more accurate models for the ET of irrigated turfgrass.

Checksum

9bf1c8c75a2e693c1ea625533fe7059f

Recommended Citation

Meza, Karem, "Water Use by Irrigated Turfgrass and Connections to Climate and Biophysical Processes" (2025). All Graduate Theses and Dissertations, Fall 2023 to Present. 408.
https://digitalcommons.usu.edu/etd2023/408