Jump Alistair S, Peñuelas Josep
Unitat d'Ecofisiologia Centre de Recerca Ecològica i Aplicacions Forestals--Centre d'Estudis Avançats de Blanes--Consejo Superior de Investigaciones Científicas, Edifici C, Universitat Autònoma de Barcelona, Catalonia, Spain.
Proc Natl Acad Sci U S A. 2006 May 23;103(21):8096-100. doi: 10.1073/pnas.0510127103. Epub 2006 May 12.
Habitat fragmentation poses a serious threat to plants through genetic changes associated with increased isolation and reduced population size. However, the longevity of trees, combined with effective seed or pollen dispersal, can enhance their resistance to these effects. The European beech (Fagus sylvatica) dominates forest over large regions of Europe. We demonstrate that habitat fragmentation in this species has led to genetic bottlenecks and the disruption of the species' breeding system, leading to significantly elevated levels of inbreeding, population divergence, and reduced genetic diversity within populations. These results show that, in contrast with the findings of previous studies, forest fragmentation has a negative genetic impact, even in this widespread, wind-pollinated tree. The identification of significant effects of forest fragmentation in beech demonstrates that trees are not at reduced risk from environmental change. This should be accounted for in the management of remaining natural and seminatural forest throughout the world.
栖息地破碎化通过与隔离增加和种群规模减小相关的基因变化，对植物构成严重威胁。然而，树木的长寿，再加上有效的种子或花粉传播，能够增强它们对这些影响的抵抗力。欧洲山毛榉（Fagus sylvatica）在欧洲大片地区的森林中占主导地位。我们证明，该物种的栖息地破碎化已导致基因瓶颈和物种繁殖系统的破坏，从而导致近亲繁殖水平显著升高、种群分化以及种群内遗传多样性降低。这些结果表明，与先前研究的结果相反，森林破碎化具有负面的遗传影响，即使在这种广泛分布、靠风授粉的树木中也是如此。对山毛榉森林破碎化显著影响的识别表明，树木并非因环境变化而面临较低风险。这一点在全球剩余天然林和半天然林的管理中应予以考虑。
