Using multiple seedlots in restoration planting enhances genetic diversity compared to natural regeneration in fragmented tropical forests

Catastrophic degradation of forests is ongoing worldwide and leads to severe forest fragmentation. Restoration plantings are often necessary to restore fragmented forests, complementing the limited natural regeneration. High genetic diversity is critical for the long-term viability of restored forests. However, there is limited knowledge of whether planted populations capture a genetic variation comparable to natural populations. We measured the efficiency of two forest restoration strategies using the common tropical oak Quercus bambusifolia. The multi-seedlot planting was established over ten years by collecting seeds from several locations in fragmented secondary forests of Hong Kong, while the single seedlot planting was established in just one year with seeds from a single natural location. We analysed the genetic diversity and genetic structure from both plantings and compared them with natural populations. The multi-seedlot planting exhibited a higher rate of genetic recovery, gr...

全球范围内森林正持续发生灾难性退化，并引发严重的森林片段化（forest fragmentation）。恢复造林（restoration plantings）往往是修复片段化森林的必要手段，可弥补自然更新（natural regeneration）能力的不足。高遗传多样性（genetic diversity）对于恢复森林的长期存续能力至关重要。然而，目前学界对人工种植种群能否捕获与天然种群相当的遗传变异仍知之甚少。本研究以常见的热带栎类植物竹叶青冈（Quercus bambusifolia）为研究对象，评估了两种森林恢复策略的效果。多源种源（multi-seedlot）造林方案耗时十余年完成，其种子采集自香港多个片段化次生林区域；单源种源（single seedlot）造林方案则仅耗时一年，种子仅取自单个天然种群区域。研究人员对两种造林方式的遗传多样性（genetic diversity）与遗传结构（genetic structure）进行了分析，并将其与天然种群进行对比。多源种源造林方案展现出更高的遗传恢复速率，