Effects of biotic and abiotic factors on the MVPS variation
The contributions of edaphic, topography and spatial factors to the variation of MVPS are similar to their contributions to the variation of methylation rates. In the recovering forest, soil, topography and spatial factors showed significant contribution to the variation of MVPS via BD, P, mean elevation, convex and spatial distance, respectively, but DBH and individual genetic background did not show significant effects on MVPS (Table 1). In native forests, only the aspect of topographic factors showed significant effects on MVPS (Table 1). Therefore, an individual reactive mechanism in recovering forests has a significant relationship with soil and spatial factors, but in native forest, this relationship disappears. MVPS variation in the recovering stand is negatively correlated with TP and AP and was significantly positively correlated with BD.
Epigenetic spatial autocorrelation analysis showed that only among DBH<40 cm individuals in recovering stands is there a significant positive spatial autocorrelation in the 140 m range and a significant negative correlation in the range of 220–440 m (Fig. 4a). For other subpopulations, there was no significant spatial autocorrelation (Fig. 4b, c, d). C. chinensis populations did not show significant genetic spatial autocorrelation in all four individual sets (Fig. 4e–h).