Fig. 1.

NRI and NTI for native versus introduced species (a, d), for naturalized versus non-naturalized introduced species (b, e), and for invasive versus non-invasive naturalized species (c, f) for China as a whole and for the eight selected province-level regions. Species pools used in calculating NRI and NTI included all (introduced plus native) species in panels a and d, all introduced (naturalized plus non-naturalized) species in panels b and e, and all naturalized (invasive plus non-invasive) species in panels c and f. Species pools for different plant groups in each province-level region included only respective species in the region.