Czyżewski Szymon, Svenning Jens-Christian
Center for Ecological Dynamics in a Novel Biosphere (ECONOVO), Department of Biology, Aarhus University, Aarhus, Denmark.
Nat Plants. 2025 May;11(5):985-1000. doi: 10.1038/s41477-025-01981-3. Epub 2025 Apr 14.
Temperate forest plant diversity is declining despite increasing conservation efforts. The closed forest paradigm, emphasizing dense, continuous canopy cover, dominates current forest management strategies. However, this approach may overlook the historical role of large herbivores in maintaining semi-open forest conditions. Here we analyse the light and herbivory preferences of 917 native temperate forest plant species across central and western Europe, comparing these preferences with light availability in untouched closed-canopy forests and pasture woodlands. Plant species are 0.1-10 Myr old, with phylogenetic conservatism in habitat affinities (niche optima); thus, their distribution reflects long-term environmental states. We found that most temperate forest plants favour heterogeneous, semi-open-canopy conditions associated with high large-herbivore impacts, rather than uniform closed-canopy environments. On the basis of Red List criteria, high-affinity forest plants associated with higher herbivory and lower herbaceous biomass face higher extinction risk, indicating that low large-herbivore densities drive extinctions in present-day forests. These results align with palaeoecological evidence and high biodiversity in modern open woodlands, suggesting that closed-canopy dominance is a recent consequence of human-driven herbivore loss. Recognizing the role of large herbivores in maintaining semi-open vegetation offers new insights for biodiversity conservation and challenges the suitability of closed-canopy models in forest management.
尽管保护力度不断加大，但温带森林植物多样性仍在下降。强调茂密、连续树冠覆盖的封闭森林范式主导着当前的森林管理策略。然而，这种方法可能忽略了大型食草动物在维持半开放森林条件方面的历史作用。在此，我们分析了欧洲中部和西部917种本地温带森林植物物种对光照和食草作用的偏好，并将这些偏好与未受干扰的封闭树冠森林和牧场林地的光照可利用性进行了比较。植物物种的历史有0.1 - 1000万年，在栖息地亲和力（生态位最优值）方面具有系统发育保守性；因此，它们的分布反映了长期的环境状态。我们发现，大多数温带森林植物偏好与大型食草动物高影响相关的异质、半开放树冠条件，而非均匀的封闭树冠环境。根据红色名录标准，与较高食草作用和较低草本生物量相关的高亲和力森林植物面临更高的灭绝风险，这表明当今森林中大型食草动物密度低会导致物种灭绝。这些结果与古生态证据以及现代开阔林地的高生物多样性相一致，表明封闭树冠主导是人类导致食草动物减少的近期后果。认识到大型食草动物在维持半开放植被中的作用为生物多样性保护提供了新见解，并对森林管理中封闭树冠模型的适用性提出了挑战。
