Data from: Impacts of selective logging on inbreeding and gene flow in two Amazonian timber species with contrasting ecological and reproductive characteristics

Selective logging in Brazil allows for the removal of up to 90% of trees above 50 cm diameter of a given timber species, independent of a species’ life history characteristics or how quickly it will recover. The genetic and demographic effects of selective logging on two Amazonian timber species (Dipteryx odorata Leguminosae, Jacaranda copaia Bignoniaceae) with contrasting ecological and reproductive characteristics were assessed in the same forest. Genetic diversity and gene flow were characterized by genotyping adults and seed sampled before and after logging, using hypervariable microsatellite markers. Overall, there were no short term genetic impacts on the J. copaia population, with commercial application of current Brazilian forest management regulations. In contrast, for D. odorata selective logging showed a range of genetic impacts, with a 10% loss of alleles, and reductions in siring by pollen from trees within the 546 ha study area (23% to 11%) and in the number of pollen donors per progeny array (2.8 to 1.6), illustrating the importance of the surrounding landscape. Asynchrony in flowering between D. odorata trees led to trees with no breeding partners, which could limit the species reproduction and regeneration under current regulations. The results are summarised with other published studies from the same site and the implications for forest management discussed. The different types and levels of impacts associated with each species support the idea that ecological and genetic information by species, ecological guild or reproductive group are essential in helping to derive sustainable logging guidelines for tropical forests.

巴西的选择性采伐（selective logging）政策允许移除指定用材树种中胸径超过50厘米的至多90%的个体，且无需考量该物种的生活史特征或其自然恢复速率。本研究针对两种生态与繁殖特征迥异的亚马逊用材树种——豆科（Leguminosae）香脂豆（Dipteryx odorata）以及紫葳科（Bignoniaceae）雅卡兰达木（Jacaranda copaia），在同一片森林中评估了选择性采伐对二者产生的遗传与种群统计效应。研究利用高变微卫星标记（microsatellite markers），通过对采伐前后采集的成年个体与种子样本进行基因分型，解析了种群的遗传多样性与基因流情况。整体而言，在当前巴西森林管理法规的商业应用场景下，雅卡兰达木种群未出现短期遗传影响。与之形成对比的是，香脂豆种群在选择性采伐后出现了一系列遗传效应：等位基因丢失率达10%，研究区546公顷范围内的树木花粉的父本贡献率从23%降至11%，且每个子代家系的花粉供体数量从2.8降至1.6，这凸显了周边景观格局的重要性。香脂豆个体间的开花异步性导致部分植株缺乏交配伴侣，在当前法规框架下可能限制该物种的繁殖与种群更新。本研究结合该研究区域已发表的其他相关研究对结果进行了总结，并探讨了其对森林管理的启示。不同物种所受影响的类型与程度存在差异，这一结果支持了如下观点：针对物种、生态类群或繁殖类群的生态与遗传信息，是制定热带森林可持续采伐指南的必要依据。