Spatial pattern dynamics among co-dominant populations in early secondary forests in Southwest China

• 作者: Yuanfa Li Minghui Li Angang Ming Hongxiang Wang Sufang Yu Shaoming Ye
• 来源期刊: 林业研究（英文版）
• 年，卷（期）: 2021,（4）
• 所属期刊栏目: ORIGINAL PAPERS
• 页码范围: 1373-1384
• 页数: 12页
• 语种: 英文

摘要

The canopy of subtropical natural forests usually consists of several co-dominant populations (CDPs), which play a crucial role in forest structure, formation of the forest environment, and ecological function. However, little atten-tion has been given to changes in spatial patterns in CDPs during natural succession. Cyclobalanopsis glauca (Thunb.) Oerst., Quercus variabilis Blume, and Pinus yunnanensis var. tenuifolia W.C. Cheng & Y.W. Law are canopy species that form CDPs in zonal forests along the Nanpan River in southwest China. We used the g ( r ) function and its bivari-ate distribution model, g 12 ( r ), which is based on distances between pairs of points, to explore the dynamics of the three CDP species with respect to distribution patterns and spa-tial correlations in two secondary forests (one 30-year-old forest [30-YF] and one 57-year-old forest [57-YF]). The fol-lowing key results were obtained: (1) there was a clumped pattern in the 30-YF, but the intensity of aggregation varied among populations and life stages. The distribution pattern gradually shifted to become random with longer succession time (i.e., 30-YF vs. 57-YF), expansion of the observation scale ( r = 0-20 m), and at later life stages. (2) Aside from the mid-sized C. glauca trees and large P. yunnanensis trees, the trees repulsed each other at certain scales ( r = 0-2, 5-6, 11-12, 14-16 m) in the 30-YF. Almost all of the life stages in the CDPs were independently correlated. This independ-ent correlation was exacerbated by a longer succession time. (3) An increase in life stages and longer succession also promoted independent changes in intraspecific correlations. (4) Intraspecific correlations were stronger than interspe-cific correlations. Our results showed that reducing exclusive competition is essential to coexistence in CDPs. Inter- and intra-specific repulsion may occur at the same time, but intraspecific repulsion was the main driving force behind the random distributions and independent correlations.