**Appendix A**


**Table A1.** Detailed results of variables importance.


**Figure A1.** The scale of tree species variability by semi-variogram analysis.

**Figure A2.** Illustrations of forest tree species diversity calculated by the three indices (*H* , *J* and λ). (**a**) Plot with tree species information; (**b**) Statistics on the number and types of tree species in the plot; (**c**) Calculation equation of tree species diversity. In Figure A2c, S is the total number of tree species in a plot; *Pi* is the proportional abundance of species *i* relative to the total abundance of all species *S* in a plot; *InPi* is the natural logarithm of this proportion.

**Figure A3.** Predicted maps of three diversity indices (λ, *H* and *J* ) by SVM (**a**–**c**), KNN (**d**–**f**) and LR (**g**–**i**) models.
