Carbon Budget of Rubber Plantation Ecosystems: Patterns, Drivers, and Sustainable Management Implications

Rubber plantations are a key component of managed forest ecosystems. Quantifying the carbon budget is essential for assessing their carbon sequestration potential and informing sustainable management practices. However, previous studies have focused primarily on individual carbon pools or specific regions, lacking a comprehensive assessment of the carbon budget in rubber plantation ecosystems (RPEs). This study systematically synthesizes the carbon budget of RPEs based on 678 data points extracted from 58 publications. The results indicate that (1) The carbon stock of RPEs (including plant, soil (0–100 cm), and litter carbon stocks) shows an accumulation trend with stand age, increasing from an average of 113.41 ± 21.63 tC ha−1 in young plantations to 252.64 ± 24.61 tC ha−1 in over-mature plantations. (2) RPEs exhibit high photosynthetic capacity and significant carbon sequestration potential during rotation phase, with mean gross primary productivity (GPP) of 22.99 ± 2.14 tC ha−1 yr−1, mean ecosystem respiration (Reco) of 13.92 ± 2.87 tC ha−1 yr−1, and net ecosystem carbon exchange (NEE) of −9.07 ± 1.91 tC ha−1 yr−1. (3) The carbon sequestration capacity of RPEs is influenced by stand age, and carbon sink capacity varies across different planting regions. (4) RPEs act as carbon sinks during rotation phase (−9.07 ± 1.91 tC ha−1 yr−1), with mean carbon storage of 196.13 ± 23.58 tC ha−1 (comprising plant biomass, litterfall, and soil carbon stocks of 70.25 ± 17.47, 2.50 ± 1.30, and 123.38 ± 14.47 tC ha−1, respectively). This synthesis provides representative baseline values for RPEs carbon dynamics, offering a scientific foundation for assessments of carbon sequestration potential and management practices.