The Modified Brière Equation and Its Applications.

Area of Science:

• Ecology
• Mathematical Biology
• Agronomy

Background:

• The Brière equation (BE) models insect development rates and is adapted for plant growth.
• The integrated BE is used as a sigmoid growth equation for plant biomass accumulation.
• Existing BE-based models show discrepancies with empirical crop growth data, particularly regarding growth start time.

Purpose of the Study:

• To modify the Brière equation (BE) by introducing an additional parameter, creating the modified Brière equation (MBE).
• To enhance the elasticity of the sigmoid growth equation for improved data fitting in plant growth studies.
• To compare the goodness of fit between BE and MBE sigmoid growth equations using plant height and biomass data.

Main Methods:

• Modified the Brière equation (BE) by adding a parameter to create the modified Brière equation (MBE).
• Fitted sigmoid growth equations based on both BE and MBE to plant height and biomass data for 15 plant species.
• Assumed zero growth start time for all model fittings.
• Evaluated goodness of fit using root-mean-square errors and absolute percentage error.

Main Results:

• The modified Brière equation (MBE) demonstrated a superior goodness of fit compared to the Brière equation (BE) for most plant species studied.
• MBE showed improved elasticity in fitting plant growth data, including height and biomass.
• The study confirmed MBE's effectiveness in capturing plant ontogenetic and population growth dynamics.

Conclusions:

• The modified Brière equation (MBE) provides a more accurate and flexible tool for modeling plant growth.
• MBE enhances the quantitative analysis of plant ontogeny and population dynamics.
• This improved model aids in understanding and predicting plant biomass accumulation and height increase over time.