Table 1.
Taxonomic rank, life form and habitat of five species and precipitation properties of study sites.
Figure 1.
Root anatomical traits along five orders for five species.
Root diameter, stele diameter and cortex thickness (A), and stele to root diameter ratio (B) for the first five root orders in five species. (A) Root and stele diameter are indicated by open circle and closed circle respectively, and cortex thickness are shown by grey square. Error bars represent one standard error of the mean. Significant difference (P<0.05) for a trait among root orders within individual species is indicated by different lower or upper case letters. See Table 1 for species abbreviations.
Figure 2.
Conduit traits along five orders for five species.
Conduit density (A), conduit diameter (B), conduit wall thickness (C) and conduit thickness to span ratio (D) among the first five orders of five species. Error bars represent one standard error of the mean. Lowercase letters that differ among root branches within a species indicate a significant difference (P<0.05). Abbreviations for species are given in Table 1.
Table 2.
The presence rate of mycorrhizal colonization (MC), secondary xylem (SX) and continuous cork layer (CCL) by root orders within each species.
Figure 3.
Results of clustering analysis of root branches.
The Results of hierarchical clustering analysis of root orders for total species (A) and each of the five species (B-F). Clusters of root orders are based on the rescaled distance for the close pairwise distance indicating these orders are similar to each other. R1to R5 represents the first to the fifth root orders. Abbreviations for species are given in Table 1.
Figure 4.
Relationships between conduits density and diameter.
The relationships between conduits density and hydraulic weighted conduit diameter for all species (A), lower orders (closed circles) and higher orders (open circles) (B). See Figure 5 for the lower and higher orders’ classification of each species. Linear regressions with log-transformed data are as detailed in insets with solid line for all species (A) and the lower orders (B), and with dash line for the higher orders in (B). *, **and *** are the significant level at 0.05, 0.01 and 0.001, respectively.
Figure 5.
Relationships between conduits density and diameter for each species.
The relationships between conduits density and hydraulic weighted conduit diameter for lower and higher orders in each of five species. The lower (closed circles) and higher orders (open circles) are classified by the presence of secondary xylem. Significant regressions are indicated as solid lines and dotted line are noted as non-significant regressions. *, **and *** represent the significant level at 0.05, 0.01 and 0.001, respectively. See Table 1 for species abbreviations.
Table 3.
Coefficient of variance (CV) for conduit diameter and density in lower orders.