Vegetation and soils are taking up approximately 30% of anthropogenic carbon dioxide emissions because of small imbalances in large gross carbon exchanges from productivity and turnover that are poorly constrained. We combined a new budget of radiocarbon produced by nuclear bomb testing in the 1960s with model simulations to evaluate carbon cycling in terrestrial vegetation. We found that most state-of-the-art vegetation models used in the Coupled Model Intercomparison Project underestimated the radiocarbon accumulation in vegetation biomass. Our findings, combined with constraints on vegetation carbon stocks and productivity trends, imply that net primary productivity is likely at least 80 petagrams of carbon per year presently, compared with the 43 to 76 petagrams per year predicted by current models. Storage of anthropogenic carbon in terrestrial vegetation is likely more short-lived and vulnerable than previously predicted.

中文翻译：

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炸弹放射性碳证据表明陆地植被具有强大的全球碳吸收和周转能力


植被和土壤约占人为二氧化碳排放量的 30%，这是因为生产力和周转率受到严格限制而导致的大量总碳交换存在轻微不平衡。我们将 20 世纪 60 年代核弹试验产生的放射性碳新预算与模型模拟相结合，以评估陆地植被的碳循环。我们发现耦合模型比对项目中使用的大多数最先进的植被模型都低估了植被生物量中的放射性碳积累。我们的研究结果，结合植被碳储量和生产力趋势的限制，意味着目前净初级生产力可能至少为每年 80 拍克碳，而当前模型预测的每年为 43 至 76 拍克。陆地植被中的人为碳储存可能比之前预测的更短命且更脆弱。