Research Highlights: Management of the risks forests are exposed to is based on the dynamics of the composition and structure of the stands and the forest. Background and Objectives: This study aimed to document the dynamics of the composition and structure of stands and forest in the Romanian Carpathians over the last five decades, as well as estimate the forecast composition of the forest in the near future (i.e., 2070). Materials and Methods: The obtained results were based on long-term monitoring and analysis of the species and structures in the stands in long-term research areas (over five decades). We performed an inventory of all the trees (on 7.5 ha) in order to characterize the stand structure in sampling plots of 0.25–1.0 ha, located in representative stands of five forest formations. Bitterlich sampling was performed in order to determine the composition of each stand (on 2930.4 ha). The future composition was established in accordance with the characteristics of the natural forest types and was based on seedling dynamics and forest management plans. Results: In mixed beech–coniferous stands, over the last five decades, the area of beech has increased by 38%, while conifers have decreased proportionally—fir by 31% and spruce by 5%. The seedling area increased from 23% to 65%, with fir contributing 22% to the composition and beech 42%. Stand density decreased by an average of 14%, with the current increment decreasing by 3.8%. The slenderness index for fir decreased from 73 to 61. In the near future, there will be an increase in the proportion of fir, from 15 to 33%, and a reduction in beech, from 49 to 45%. The proportion of spruce will be reduced from 17 to 12%. Conclusions: Based on the forest dynamics, management adaptation strategies need to be developed to improve the stability of the forest ecosystems.

中文翻译：

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罗马尼亚喀尔巴阡山脉五年管理后的森林动态

研究重点：森林面临的风险管理基于林分和森林的组成和结构的动态。背景和目标：本研究旨在记录过去 50 年罗马尼亚喀尔巴阡山脉林分和森林的组成和结构动态，并估计在不久的将来（即 2070 年）森林的预测组成。材料和方法：获得的结果基于对长期研究区（超过 50 年）中林分物种和结构的长期监测和分析。我们对所有树木（7.5 公顷）进行了清点，以表征 0.25-1.0 公顷采样地块中的林分结构，位于五个森林形成的代表性林分中。进行 Bitterlich 采样以确定每个林分的组成（2930.4 公顷）。未来的组成是根据天然林类型的特点，根据苗木动态和森林经营计划确定的。结果：在山毛榉-针叶混交林中，在过去的 50 年中，山毛榉的面积增加了 38%，而针叶树的面积则按比例减少——冷杉减少了 31%，云杉减少了 5%。幼苗面积从 23% 增加到 65%，其中杉木占 22%，山毛榉占 42%。林分密度平均下降 14%，当前增量下降 3.8%。冷杉的细长指数从73下降到61。在不久的将来，冷杉的比例将从15%增加到33%，山毛榉的比例将从49%下降到45%。云杉的比例将从17%降低到12%。结论：基于森林动态，需要制定管理适应策略以提高森林生态系统的稳定性。