Institute of Biology/Geobotany and Botanical Garden, Martin Luther University Halle Wittenberg Am Kirchtor 1, 06108 Halle (Saale), Germany.
Ecol Evol. 2011 Nov;1(3):290-305. doi: 10.1002/ece3.23.
Using molecular fingerprinting (amplified fragment length polymorphism [AFLP] method), we explored the potential of small-scale population analysis for understanding colonization patterns of herb layer species in forests after canopy disturbance. We investigated three common forest understorey species with different life forms (Trientalis europaea, Calamagrostis villosa, and Vaccinium myrtillus) in the Harz Mountains in Germany in three different gap age classes and undisturbed forest. For two of them (T. europaea and C. villosa), we analyzed clone sizes and clonal structure. We hypothesized that clone sizes depend on age since gap formation and are affected by light availability. Mean patch sizes of V. myrtillus, T. europaea, and C. villosa formed were 3.7 m(2), 27.9 m(2), and 40.6 m(2), respectively. Trientalis europaea and C. villosa patches consisted mostly of more than one genet. Largest clone sizes of T. europaea were encountered in gaps of intermediate successional age (15-60 years, averaged minimum estimation of clone sizes: 6.56 m(2)) whereas clone size of C. villosa was found to be independent from gap age and had a mean minimum clone size of 0.49 m(2). In both species, clone size was positively related to light availability. Additionally, there was a positive relationship between clone size and ramet density for T. europaea and C. villosa. Genetic variation was higher within populations of T. europaea and C. villosa than among populations. Trientalis europaea was the only species with a clear genetic isolation by distance, pointing at an equilibrium between gene flow and genetic drift. In conclusion, we showed that forest canopy gap dynamics clearly affect the small-scale structure of populations of understorey plants. Species with high lateral growth rates, such as T. europaea offer the possibility to serve as "ecological clock" for dating ecological processes.
利用分子指纹图谱（扩增片段长度多态性 [AFLP] 方法），我们探索了通过小尺度种群分析理解林冠干扰后草本层物种定殖模式的潜力。我们在德国哈茨山脉的三个不同林隙年龄等级和未干扰森林中，对三种不同生活型的常见森林下层物种（欧洲三蕊柳、大油芒和越橘）进行了研究。对于其中两种（欧洲三蕊柳和大油芒），我们分析了克隆大小和克隆结构。我们假设克隆大小取决于林隙形成的年龄，并受光照可用性的影响。越橘、欧洲三蕊柳和大油芒形成的平均斑块大小分别为 3.7 m²、27.9 m²和 40.6 m²。欧洲三蕊柳和大油芒斑块主要由一个以上的基株组成。在中等演替年龄（15-60 年）的林隙中，欧洲三蕊柳的最大克隆大小最大（平均最小克隆大小估计：6.56 m²），而大油芒的克隆大小与林隙年龄无关，平均最小克隆大小为 0.49 m²。在这两个物种中，克隆大小与光照可用性呈正相关。此外，欧洲三蕊柳和大油芒的克隆大小与分株密度呈正相关。欧洲三蕊柳和大油芒种群内的遗传变异高于种群间的遗传变异。欧洲三蕊柳是唯一具有明显遗传隔离距离的物种，表明基因流和遗传漂变之间达到了平衡。总之，我们表明林冠间隙动态明显影响了草本植物种群的小尺度结构。具有高侧向生长速度的物种，如欧洲三蕊柳，为记录生态过程提供了可能。
