Thinning altered the optimum photosynthetic environment in a subtropical coniferous plantation

作者：Shengtong Li, Mingjie Xu, Fengting Yang, Jiaxin Song, Xinyi Shi, Ziyi Wang, Huimin Wang, Xianjin Zhu, Chuanpeng Cheng, Jianlei Wang, T. T. Zhang · 发表于：Scientific Reports · 年份：2026 · DOI：10.1038/s41598-026-35052-0 · 被引用次数：1 · 研究领域：Plant Water Relations and Carbon Dynamics、Remote Sensing in Agriculture、Remote Sensing and LiDAR Applications

Abstract Thinning offers long-term benefits for planted forests and is an important silvicultural practice. Meanwhile, ecosystem would respond to thinning and the optimal photosynthetic environment would change. Clarifying and quantifying the changing optimal photosynthetic environment induced by thinning is important for accurate prediction of carbon budgets and effective management of artificial forests. Based on six-year continuous in situ observations of carbon fluxes and corresponding environmental factors before and after 25% thinning in a typical subtropical plantation in China, this study revealed that thinning increased the optimum values of key environmental factors (net radiation (Rn), air temperature (Ta), and vapor pressure deficit (VPD)) for gross primary productivity (GPP). Meanwhile, thinning enhanced the ecosystem maximum GPP (GPP max ) corresponding to each single optimum environmental factor. Among them, the highest GPP max , reaching 0.91 mg CO 2 m − 2 s − 1 , was found when Rn reached the optimum value and was 13% higher than that before thinning. In addition, the optimum photosynthetic environment configurations (the combination of multiple environmental factors) that could occur in the real world were detected and quantified. Before thinning, the optimal environment configuration was Rn = 692.85 J m − 2 s − 1 , Ta = 23.43 °C, VPD = 0.96 kPa and SWC = 0.20 m 3 m − 3 , with a GPP max of 0.98 mg CO 2 m − 2 s − 1 . After thinning, the GPP max increased to 1...