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

Abstract

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 a 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 showed negative associations with contemporary other tree species. Our results suggested that canopy disturbance caused by canopy trees and gap partitioning among the coexistent tree species are important for the persistence of the mixed forest. As a main gapmaker, B. albosinensis appear to develop a self‐perpetuating life‐history trait and allow them to persist.

Contrasting Responses of Rhizosphere Bacteria, Fungi and Arbuscular Mycorrhizal Fungi Along an Elevational Gradient in a Temperate Montane Forest of China

“…Our study was conducted on Taibai Mountain, Shaanxi Province, China (33°49–34°10′N; 107°19′–107°58′E, Figure 1A ), which spans from 530 to 3767 m in elevation and is the highest mountain in the Qinling Mountain range. The Qinling Mountains run east–west in central China and form a transitional zone between northern subtropical and warm-temperate zones, which make it a global biodiversity hotspot ( Dang et al, 2007 ; Guo et al, 2019 ). Taibai Mountain is in the northern slope of range and is in a warm temperate region.…”

Forest Understorey Vegetation: Colonization and the Availability and Heterogeneity of Resources

“…Generally, large canopy gaps caused by windthrow and insect outbreaks increase light availability, soil temperatures, soil nutrients, and coarse woody debris, all of which are more favorable for the growth of vascular plants [8,31]. Conversely, small canopy gaps caused by density-dependent canopy mortality and stand self-thinning have negligible effects on the abundance and diversity of vascular plants, due to their minimal impact on resource availability in the understorey layer [43]. Increases in resource heterogeneity-such as tip-up mounds and diverse coarse woody debris classes, result in abundant growth spaces and substrate sources, which enhance the abundance and diversity of non-vascular plants [8,21,39].…”

Assessment of Natural Regeneration of Different Forms of Gaps in Atrush Forest

“…While we find that the triangular shape formed a percentage (8 %) of the total shapes of gaps distributed in different proportions over the space categories for the gaps, where we find in the small area category (X < 200) m 2 the shape of the ratio (34 %), and in the second area category (200 < X < 400) m 2 ratio (25 %), while in regular forms of the fourth area category are (71 %), and this indicates that the oval and regular forms are the most common forms in the gaps, and there is no doubt that regular forms are prevalent in the study site (Guo et al, 2019;Pawlikowski et al, 2019;De Lima et al, 2013…”