Simulating climatic responses of vegetation production with ecological optimality theories

作者：Zhongmin Hu, Chuan Jin, Siyuan Peng, Yue Yang, Guojiao Yang, Nicholas G. Smith · 发表于：The Innovation Geoscience · 年份：2025 · DOI：10.59717/j.xinn-geo.2025.100153 · 被引用次数：6 · 研究领域：Plant Water Relations and Carbon Dynamics、Plant responses to elevated CO2、Ecosystem dynamics and resilience

<p>Ecosystem gross primary productivity (GPP) is a fundamental ecosystem function. Accurately predicting variations in GPP in response to environmental changes is a key task for the modelling community. Although sharing the same photosynthesis module, land models show divergent predictions of GPP in response to environmental changes. One reason causing the uncertainties is that key parameters of the photosynthesis module, e.g., stomatal conductance, maximum rate of Rubisco carboxylation (<i>V</i><sub>cmax</sub>), are fixed default values or estimated with empirical functions. To solve this issue, here we integrate three well-accepted optimality theories for plant photosynthesis, i.e., (1) plants maximize carbon gain for a unit of water loss through optimizing stomatal conductance, (2) plants minimize the summed cost of maintaining transpiration and carboxylation through optimizing partial pressure of CO<sub>2</sub> in the intercellular space (<i>C</i><sub>i</sub>), and (3) vegetation allocates resources in a coordinated manner to operate close to the intersection of the light-limited and Rubisco-limited carbon assimilation rates. By bridging these theories, the key parameters of photosynthesis are estimated with analytical equations, without additional empirical constraining functions. Thereafter, an optimality-based model (Opt model) is developed to estimate GPP in this study. The Opt model is driven by leaf a...