Canopy disturbance and gap partitioning promote the persistence of a pioneer tree population in a near-climax temperate forest of the Qinling Mountains, China

An unresolved question of temperate forests is how pioneer tree species persist in mature forests. In order to understand the responsible mechanisms, we investigated a near-climax mixed temperate forest dominated by Betula albosinensis in the Qinling Mountains of China. Through establishing four 50 m × 50 m plots, we examined the canopy disturbance characteristics and its effects on tree recruitments. We further test the intra- and interspecific effects on the recruitment of B. albosinensis. The obtained data demonstrated canopy disturbance was frequent but most small-sized. The canopy gaps are caused mainly by adult B. albosinensis by snapping. The regeneration of coexistent tree species shows distinct preference for gap size. B. albosinensis were clumped at the juvenile stage and small scales. B. albosinensis juveniles were positively associated with B. utilis juveniles and negatively associated with the conspecific and B. utilis large trees. In addition, B. albosinensis juveniles sho...

温带森林领域一个尚未解决的科学问题是：先锋树种如何在成熟林中长期存续。为探明其背后的作用机制，我们在中国秦岭地区选取了一片以红桦（Betula albosinensis）为优势种的近顶极温带混交林作为研究对象。通过设置4块50米×50米的样地，我们分析了林冠干扰的特征及其对林木更新的影响。此外，我们还探究了种内与种间作用对红桦更新的影响。监测数据显示，研究区内林冠干扰发生频繁，但多数规模较小。林隙主要由成年红桦的折断倒伏所形成。伴生树种的更新表现出对林隙大小的显著偏好性。红桦幼树在小尺度范围内呈聚集分布格局。红桦幼树与糙皮桦（Betula utilis）幼树呈正相关关系，而与同种成年个体及糙皮桦成年个体呈负相关关系。此外，红桦幼树还……