A simple new method to determine leaf specific heat capacity.

Area of Science:

• Plant Physiology
• Thermal Imaging
• Agricultural Science

Background:

• Accurate plant transpiration quantification is vital for agriculture and plant science.
• Current thermal imaging methods are limited by difficulties in determining leaf specific heat capacity (Cp).
• Existing literature provides only rough estimates of Cp, lacking simple, accurate determination methods.

Purpose of the Study:

• To develop a non-invasive method for quantifying leaf specific heat capacity (Cp).
• To enable more accurate thermal imaging of plants under natural, non-steady state conditions.

Main Methods:

• Developed a non-invasive technique to quantify k (leaf thickness * density * Cp).
• Fitted a leaf energy balance model to leaf temperature transients during and after a short light pulse.
• Calculated Cp by dividing k by leaf thickness and density.

Main Results:

• Quantified Cp for 13 horticultural and tropical plant species, with values ranging from 3200-4000 J kg⁻¹ K⁻¹.
• Found a positive correlation between Cp and leaf water content.
• Observed that leaf thickness significantly influences temperature response in species like Phalaenopsis amabilis.

Conclusions:

• The developed method allows for easy determination of leaf Cp across different plant species.
• This advancement facilitates more accurate thermal imaging applications in plant science and agriculture.