[Detecting leaf and twig temperature of some trees by using thermography]

Area of Science:

• Plant physiology
• Remote sensing
• Thermal imaging

Background:

• Noninvasive temperature detection using thermography is valuable across scientific fields.
• Monitoring leaf and twig temperatures in trees under environmental stress is crucial for understanding plant health.

Purpose of the Study:

• To investigate the use of thermography for noninvasively detecting temperature variations in tree leaves and branches.
• To measure leaf and twig temperatures during increasing temperatures under direct sunlight.
• To analyze the relationship between temperature, water content, transpiration capacity, and visible plant damage.

Main Methods:

• Leaf and twig temperatures were monitored using thermography during controlled heating.
• Specific heat and latent heat differences were measured based on varying water content and transpiration.
• Sweetgum leaves (Liquidambar styraciflua L.) were subjected to vein severing to create localized water stress for comparative analysis.
• Thermoimages were analyzed to identify temperature gradients and high-temperature areas.

Main Results:

• Thermography successfully detected leaf and twig temperatures, including scorch and branch dieback.
• Transpiration cooling failure in sweetgum leaves was accurately measured.
• Vein-severed sweetgum leaves exhibited temperature gradients, facilitating accurate thermal imaging.
• A strong correlation was observed between high-temperature areas identified by thermography and reddened leaf lamina.

Conclusions:

• Thermography is an effective noninvasive tool for assessing plant temperature and identifying water stress in trees.
• The study demonstrated the utility of thermography in detecting transpiration failure and localized damage.
• The vein-severing technique provided a reliable method for studying leaf temperature dynamics and thermal anomalies.