Abstract

Photosynthesis is vital to life on Earth, as it promotes plant growth and sustains the environment. For C3 plants in particular, understanding photosynthetic rate is a prerequisite for more accurate yield estimates and for understanding their responses to environmental changes. The Farquhar-von Caemmerer-Berry (FvCB) is one of the most common biochemical models of carbon assimilation in photosynthesis, based on leaf-level gas exchange. We estimate photosynthesis in C3 plants using the FvCB model, which relates Rubisco carboxylation (vcmax) to electron transport (J) and TPU. We attempt to improve the model's estimates of accuracy across varied combinations of stimuli, as a function of environmental measures of light, CO2, temperature, and stomatal conductance. The model was then evaluated using a set of selected representative C3 plant species, and the simulations were also compared with real-time gas exchange measurements. The model output shows that it performs well at estimating photosynthesis responses to changing climate conditions. Moreover, Vcₘₐₓ, J, and overall assimilation rates exhibited exceptional interspecific variability, further quantifying the sensitivity analysis and indicating the need for species-specific parameterization. Our study contributes to developing more robust photosynthetic models for crops and ecosystems that estimate climate change impacts and support agricultural management strategies that rely on them.