The anatomical and compositional basis of leaf mass per area

Area of Science:

• Plant Ecology
• Leaf Physiology
• Ecosystem Science

Background:

• Leaf dry mass per unit leaf area (LMA) is a crucial ecological trait.
• The anatomical and compositional drivers of LMA have remained largely undefined.

Purpose of the Study:

• To develop a quantitative framework for understanding LMA.
• To link leaf cellular and tissue characteristics to LMA variation.

Main Methods:

• Developed a mathematical and physical model to quantify LMA determinants.
• Analyzed cell and tissue properties in 11 diverse broadleaved woody angiosperm species.

Main Results:

• The model explained a significant portion of LMA variation (R² = 0.94).
• High LMA was associated with larger cell size, increased major vein allocation, more mesophyll cell layers, and higher cell mass density.
• These findings held true across diverse species and in evergreen vs. deciduous angiosperms.

Conclusions:

• An explicit framework can effectively explain LMA based on leaf anatomy and composition.
• This approach connects leaf traits to physiological, evolutionary, community, and macroecological processes.