Sprouting characteristics and elevation differentiation patterns of woody plants in the Baima Snow Mountain, China.

Abstract

We investigated the composition and diversity of sprouting plants across forest communities along an elevation gradient (3155-3979 m) in the Baima Snow Mountain, and examined the variations in sprouting ability among taxonomic groups (families, genera, and species) and growth forms (trees and shrubs). The results showed that a total of 4211 woody plants exhibited sprouting behavior across five plots. These plants belonged to 38 species, 22 genera and 12 families, representing 95.0%, 95.7% and 92.3% of the total community. Rhododendron rigidum exhibited the highest number of sprouting stems (3311), while Rhododendron wardii showed the highest sprouting rate (70.1%). The number and composition of sprouting species varied across elevations. From the lowest to highest elevation (3155, 3382, 3685, 3802, and 3979 m), the number of sprouting was 17, 15, 12, 11 and 15, accounting for 85.0%, 75.0%, 85.7%, 84.6%, and 88.2% of the total species at each elevation respectively. The species with the highest number of sprouts stems differed by elevation: R. rigidum (3155 and 3382 m), Rhododendron fortunei (3685 m), Lonicera tangutica (3802 m), and R. wardii (3979 m). The species with the highest sprouting rate was Quercus semecarpifolia (3155 m), followed by R. fortunei (3382 and 3685 m), L. tangutica (3802 m), and R. wardii (3979 m). The number of sprouting stems for both trees and shrubs, as well as the sprouting rates for trees, showed a trend of first increasing and then decreasing with elevation. In contrast, the sprouting rate of shrubs showed no significant variation. The richness of tree-form sprouting plants showed a single-peak pattern, with the highest richness at 3685 m, whereas shrub-form sprouting plants richness showed an inverse mid-domain pattern, initially decreasing with elevation before increasing again. Sprouting was a prevalent phenomenon in montane forest ecosystems, and the sprouting capacities of different growth forms exhibited significant elevational patterns.