@article{Wang2025, 
author = {Yanfang Wang and Liang Wei and Liheng Zhong and Xizi Yu and Pengtao Huang and Fang Wang and John D. Marshall},
title = {Adding a storage pool improves 3-PG tree-ring simulations},
year = {2025},
journal = {Forest Ecosystems},
volume = {14},
number = {2},
keywords = {3-PG model, Tree-ring simulation, Tree height, Carbon storage pool},
url = {https://www.sciopen.com/article/10.1016/j.fecs.2025.100384},
doi = {10.1016/j.fecs.2025.100384},
abstract = {Tree rings provide long-term records of tree growth and climate changes, which makes them ideal benchmarks for forest modeling. Tree-ring information has greatly improved the reliability of 3-PG, which is one of the most commonly used process-based forest growth models. Here, we strengthen 3-PG's ability to simulate tree-ring width and stable carbon isotopes (δ13C) by enhancing its descriptions of tree physiology. The major upgrade was adding a carbon storage pool for tree-ring formation using stored carbohydrates. We also incorporated previous modifications (replacing the age modifier with a height modifier) of 3-PG and tested their efficacy in improving tree-ring simulations. We ran the model based on two grand fir (Abies grandis) stands. The updated model greatly improved the simulations for both tree-ring widths and δ13C. The results represent one of the best tree-ring δ13C simulations, which accurately captured the amplitude in annual variations of δ13C. The correlations (R2) between simulations and observations reached 0.50 and 0.73 ​at two stands, respectively. The new model also greatly improved the simulations of raw tree-ring widths and detrended ring-width index (RWI). Because of better descriptions of tree physiology and more accurate simulations of tree rings than the previous model version, the updated 3-PG should provide more reliable simulations than previous 3-PG versions when tree-ring information is used as a benchmark in future studies.}
}