French forests exhibit the fastest relative changes across Europe. Growing stock increases faster than area, and is greatest in low-stocked private broadleaved forests. Past areal increases and current GS levels show positive effects on GS expansion, with GS increases hence expected to persist. Strong increases in growing stocks (GS) of European forests for decades remain poorly understood and of unknown duration. French forests showing the greatest relative changes across Europe form the investigated case study. The magnitudes of net area, GS, and GS density (GSD) changes were evaluated across forest categories reflecting forest policy and land-use drivers. The roles of forest areal changes, GS and GSD levels on GS changes were investigated. National Forest Inventory data were used to produce time series of area, GS and GSD across forest categories over 1976–2014, and exploratory causal models of GS changes. GS (+ 57%) increased three times faster than area, highlighting an advanced stage in the forest transition. Low-stocked private forests exhibited strong changes in GS/GSD, greatest in private broadleaved forests, stressing the contribution of returning forests on abandoned lands. Regression models demonstrated positive effects of both past areal increases and current GS, on GS expansion. Aerial C-sink in French forests is expected to persist in future decades.

中文翻译：

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法国森林蓄积量连续十年空前增加，并以私人阔叶林为主

法国森林在整个欧洲表现出最快的相对变化。立木蓄积增长速度快于面积，在低蓄积的私有阔叶林中最为明显。过去的面积增加和当前的 GS 水平显示出对 GS 扩张的积极影响，因此预计 GS 的增加将持续下去。几十年来欧洲森林蓄积量（GS）的强劲增长仍然知之甚少，持续时间未知。法国森林在整个欧洲显示出最大的相对变化，形成了调查案例研究。对反映森林政策和土地利用驱动因素的森林类别的净面积、GS 和 GS 密度 (GSD) 变化的幅度进行了评估。研究了森林面积变化、GS 和 GSD 水平对 GS 变化的作用。国家森林清单数据用于生成面积的时间序列，1976-2014 年间森林类别的 GS 和 GSD，以及 GS 变化的探索性因果模型。GS (+ 57%) 的增长速度是面积的三倍，突出了森林转型的高级阶段。低蓄积的私有林在 GS/GSD 中表现出强烈的变化，在私有阔叶林中变化最大，强调了回归森林对废弃土地的贡献。回归模型证明了过去面积增加和当前 GS 对 GS 扩张的积极影响。法国森林中的空中 C 型汇预计将在未来几十年内持续存在。强调在废弃土地上恢复森林的贡献。回归模型证明了过去面积增加和当前 GS 对 GS 扩张的积极影响。法国森林中的空中 C 型汇预计将在未来几十年内持续存在。强调在废弃土地上恢复森林的贡献。回归模型证明了过去面积增加和当前 GS 对 GS 扩张的积极影响。法国森林中的空中 C 型汇预计将在未来几十年内持续存在。