Fig. 8

Principal component analysis (PCA) of spatial associations among trees of each plot. Plot information including its code is provided in Table 1. Spatial associations (including all associations among large trees, large trees and saplings, and among saplings of every identified tree species) presented by K-value across 0–25 m scale in each plot was used as the main matrix in PCA; and logged species selection, logging intensity and soil N concentration of each plots was submitted to PCA as second matrix (influencing factors)