Abstract Knowledge of plant aboveground and belowground biomass (AGB and BGB) allocation is fundamental for our understanding of terrestrial carbon sequestration in a changing climate. However, how multiple global change factors interactively affect biomass allocation in terrestrial ecosystems remains unclear. We used meta-analysis to synthesize main and interactive effects of global change factors on AGB, BGB, and root/shoot based on 129 multiple-factor studies. Elevated CO2 (E), nitrogen addition (N), warming (W), irrigation (I) and their combinations (EN, EW, NW, ENW, IE, IN, IW, IEN, INW and IENW) significantly increased AGB. However only half of the treatments (i.e., E, N, W, EN, EW, NW, IE and IW) stimulated BGB, leading to significant declines of root/shoot in treatments with I and/or N. Drought (D) significantly decreased both total biomass (14%) and AGB (47%), but increased root/shoot by 21% as well as DE and DW. Additive interactions between global change factors exhibited a predominance on both plant biomass (69.0%) and biomass allocation (64.8%). The proportion of synergistic interaction in AGB’s responses to multiple global change factors was greater relative to that in BGB. Response correlation between AGB and root/shoot was observed in woody plants, while, in herbaceous ones, we found the correlation between BGB and root/shoot. Our findings highlight the importance of the interactive effects among global change factors on biomass allocation. Incorporating these interactions into global vegetation models may improve predictions of future global carbon storage and could inform sustainable strategies for grassland and plantation management in a future climate.

中文翻译：

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生物量分配对多因素全球变化的响应：全球综合

摘要 植物地上和地下生物量（AGB 和 BGB）分配的知识是我们理解气候变化中陆地碳固存的基础。然而，多个全球变化因素如何相互作用地影响陆地生态系统中的生物量分配仍不清楚。基于 129 项多因素研究，我们使用荟萃分析综合了全球变化因素对 AGB、BGB 和根/茎的主要和交互作用。CO2 (E)、氮添加 (N)、升温 (W)、灌溉 (I) 及其组合（EN、EW、NW、ENW、IE、IN、IW、IEN、INW 和 IENW）显着增加了 AGB。然而，只有一半的处理（即 E、N、W、EN、EW、NW、IE 和 IW）刺激 BGB，导致在 I 和/或 N 处理中根/芽显着下降。干旱 (D) 显着降低了总生物量 (14%) 和 AGB (47%)，但使根/茎以及 DE 和 DW 增加了 21%。全球变化因素之间的加性相互作用在植物生物量 (69.0%) 和生物量分配 (64.8%) 上均表现出优势。AGB对多种全球变化因素的响应中协同作用的比例相对于BGB更大。在木本植物中观察到 AGB 与根/茎之间的响应相关性，而在草本植物中，我们发现 BGB 与根/茎之间存在相关性。我们的研究结果强调了全球变化因素之间相互作用对生物量分配的重要性。