Applied Ecology Conservation Lab, Department of Biological Sciences State, University of Santa Cruz, Ilhéus 45662-900, Brazil.
Genetics and Biotechnology Center, Department of Biological Sciences State, University of Santa Cruz, Ilhéus 45662-900, Brazil.
Genes (Basel). 2021 Dec 20;12(12):2025. doi: 10.3390/genes12122025.
The Atlantic Forest remnants in southern Bahia, Brazil, contain large tree species that have suffered disturbances in recent decades. Anthropogenic activities have led to a decrease in the population of many tree species and a loss of alleles that can maintain the evolutionary fitness of their populations. This study assessed patterns of genetic diversity, spatial genetic structure, and genetic structure among Penn. populations, comparing the genetic parameters of adult and juvenile trees. In particular, we collected leaves from adults and juveniles of in two protected areas, the Veracel Station (EVC) and the Una Biological Reserve (UBR), located in threatened Atlantic Forest fragments. We observed a substantial decay in genetic variability between generations in both areas i.e., adults' H values were higher (EVC = 0.720, UBR = 0.736) than juveniles' (EVC = 0.463 and UBR = 0.560). Both juveniles and adults showed genetic structure between the two areas (θ = 0.017 for adults and θ = 0.109 for juveniles). Additionally, forest fragments indicated an unexpectedly short gene flow. Our results, therefore, highlight the pervasive effects of historical deforestation and other human disturbances on the genetic diversity of populations within a key conservation region of the Atlantic Forest biodiversity hotspot.
巴西巴伊亚南部的大西洋森林残余地包含了许多大树种，这些树种在最近几十年中遭受了干扰。人为活动导致许多树种的数量减少，失去了维持其种群进化适应性的等位基因。本研究评估了 Penn. 种群的遗传多样性、空间遗传结构和遗传结构模式，比较了成年树和幼树的遗传参数。特别是，我们在两个受威胁的大西洋森林碎片保护区域，即 Veracel 站（EVC）和 Una 生物保护区（UBR），收集了成年和幼年的叶片。我们观察到两个区域的遗传变异性在代际间有很大的衰减，即成年人的 H 值较高（EVC=0.720，UBR=0.736），而幼树的 H 值较低（EVC=0.463，UBR=0.560）。成年个体和幼树个体在两个区域之间都表现出遗传结构（成年个体的θ=0.017，幼树个体的θ=0.109）。此外，森林片段表明基因流出乎意料地短。因此，我们的研究结果强调了历史上的森林砍伐和其他人为干扰对大西洋森林生物多样性热点关键保护区域内 种群遗传多样性的普遍影响。
