Location: Water Management and Systems Research
Title: Simple background subtraction of thermal imagery for crop water stress detection in greenhouseAuthor
Submitted to: Applied Engineering in Agriculture
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 2/20/2019 Publication Date: 5/8/2019 Citation: DeJonge, K.C., Zhang, H., Gleason, S.M. 2019. Simple background subtraction of thermal imagery for crop water stress detection in greenhouse. Applied Engineering in Agriculture. 35(3):339-344. https://doi.org/10.13031/aea.13090. DOI: https://doi.org/10.13031/aea.13090 Interpretive Summary: This study demonstrates a simple technique that uses a homogeneous background temperature that contrasts with canopy temperature, thereby allowing the canopy temperature itself to be isolated in a thermal image. Analysis of pixel temperatures and their associated statistics demonstrate the potential of this method to measure small (ca. < 0.5 °C) and rapid (ca. < 1 s) fluctuations in leaf energy balance. This technique has broad applicability in greenhouse, growth chamber, and other small-scale experiments where real time response of individual leaves or canopies is required. Technical Abstract: While infrared thermometry and thermal imagery have potential to detect crop water stress and quantify evapotranspiration, both valuable in irrigation scheduling, it is often difficult to isolate plant canopy temperature from background temperatures. In this study, we demonstrate a simple technique that uses a homogeneous background temperature that contrasts with canopy temperature, thereby allowing the canopy temperature itself to be isolated in a thermal image. Analysis of pixel temperatures and their associated statistics demonstrate the potential of this method to measure small (ca. < 0.5 °C) and rapid (ca. < 1 s) fluctuations in leaf energy balance. This technique has broad applicability in greenhouse, growth chamber, and other small-scale experiments where real time response of individual leaves or canopies is required. |