Vol20 No.3: 765-778

【Title】Adaptive mechanisms of Ardisia crenata var. bicolor along an elevational gradient on Gaoligong Mountain, Southwest China

【Author】AI Xing-mei^1,2*; LI Yu¹; XIE Huan¹; ZHAO Cai-bao^{1, 2}

【Addresses】1 College of Landscape Architecture and Horticulture Sciences, Southwest Forestry University, Kunming 650224, China; 2 Southwest Research Center for Engineering Technology of Landscape Architecture (State Forestry and Grassland Administration), Southwest Forestry University, Kunming 650224, China

【Corresponding author】AI Xing-mei

【Citation】Ai XM, Li Y, Xie H, Zhao CB (2023) Adaptive mechanisms of Ardisia crenata var. bicolor along an elevational gradient on Gaoligong Mountain, Southwest China. Journal of Mountain Science 20(3). https://doi.org/10.1007/s11629-022-7369-7

【DOI】https://doi.org/10.1007/s11629-022-7369-7

【Abstract】Plants overcome environmental stress by generating metabolic pathways. Thus, it is crucial to understand the physiological mechanisms of plant responses to changing environments. Ardisia crenata var. bicolor has an important ornamental and medicinal value. To reveal the impact of elevational gradient on the habitat soil and plant physiological attributes of this species, we collected root topsoil (0–20 cm) and subsoil (20–40 cm) samples and upper leaves at the initial blooming phase, in a survey of six elevations at 1,257 m, 1,538 m, 1,744 m, 1,970 m, 2,135 m, and 2,376 m, with 18 block plots, and 5 sampling points at each site. Temperature decreases with an increase in elevation, and soil variables, and enzymatic activities fluctuated in both the topsoil and subsoil, with all of them increasing with elevation and decreasing with soil depth. Redundancy analysis was conducted to explore the correlation between the distribution of A. crenata var. bicolor along the elevational gradient and soil nutrients and enzyme activities, the soil properties were mainly affected by pH at low elevations, and governed by total phosphorus (TP) and available nitrogen (AN) at high elevations. The levels of chlorophyll, carbohydrates, and enzymatic activity except for anthocyanin in this species showed significant variation depending on physiological attributes evaluated at the different collection elevations. The decline in chlorophyll a and b may be associated with the adaptive response to avoid environmental stress, while its higher soluble sugar and protein contents play important roles in escaping adverse climatic conditions, and the increases in activities of antioxidant enzymes except peroxidase (POD) reflect this species' higher capacity for reactive oxygen scavenging (ROS) at high elevations. This study provides supporting evidence that elevation significantly affects the physiological attributes of A. crenata var. bicolor on Gaoligong Mountain, which is helpful for understanding plant adaptation strategies and the plasticity of plant physiological traits along the elevational gradients.

【Keywords】Ardisia crenatavar. bicolor; Adaptive distribution; Elevation; Gaoligong Mountain; Plant physiological trait; Soil physicochemical properties