Figure legends
Fig. 1. Representativeness of study sites. (a) Distribution of study
sites across the southern part of the Korean peninsula. (b) Distribution
of study sites across the global vegetation biomes defined by the
Whittaker classification.
Fig. 2. Conceptual diagram of the analysis steps and data flow in
defining the floristic zonation (Kreft and Jetz, 2010).
Fig. 3. Results of the self-organizing map (SOM) analysis for 9 × 9 SOM
map. (a) The neighbor distance plot or U-Matrix indicating the distance
between each node and its neighbors. (b) The classification of the
training samples according to the SOMs.
Fig. 4. Four floristic zones mapped to the southern Korean Peninsula,
derived using plant distribution data. The straight and solid lines
represent the named historical floristic regions. The lines dividing the
historical floristic regions have previously been used to explain the
observed distribution of plants on the Korean Peninsula (e.g., north,
central, and southern Korean Peninsula).
Fig. 5. Comparison of geographic and climate factors in the derived
floristic zones on the southern Korean Peninsula. (a) latitude; (b)
longitude; (c) mean annual temperature; (d) annual precipitation; (e)
warmth index; and (f) coldness index. Median values are marked inside
the boxplots, errors bars indicates the 90th and 10th percentiles, and
the points outside of the error bars indicate outliers. A Tukey post-hoc
test revealed significance groups, represented by letters (p <
0.05).
Fig. 6. Analysis of composition ratios for physical factors in each
floristic zone on the Korean Peninsula. (a) Parent material; (b)
topography; (c) effective soil depth; and (d) soil texture.
Fig. 7. A Venn diagram showing the relationships between plant
distributions in each of the four floristic zones. Numbers represent
individual taxonomic groups.
Fig. 8. Comparison of the composition of specific plant families in each
floristic zone. As shown in Fig. 7, there were 1,099 taxa that appeared
in all 4 zones. The specific plant species in Zones I, II, III, and IV
numbered 72, 25, 192, and 404 taxa, respectively.