Data from: Multi-dimensional patterns of variation in root traits among coexisting herbaceous species in temperate steppes

1. Characterizing patterns of variation in plant traits across species and
environmental gradients is critical for understanding performance of
species in ecosystems. One-dimensional pattern of variation has been
demonstrated in leaf traits, which is known as the leaf economic spectrum.
However, it is unclear whether such a spectrum exists for root traits. 2.
For roots of 15 species from temperate grasslands, we determined
respiration rate, relative growth rate, lifespan as well as 10
morphological, chemical and anatomical root traits. We further evaluated
pairwise and multiple-trait relationships by the Pearson’s correlation and
principle component analysis including phylogenetic contrasts. 3. We found
that root functions were related to three clusters of variation. Root
respiration rate and relative growth rate were positively correlated with
average root diameter, but they were negatively correlated with specific
root length. In contrast, root lifespan was not correlated with average
root diameter, but it was positively correlated with specific root length.
These results are inconsistent with the presumption of the root economic
spectrum. 4. The principle components analysis revealed a
multi-dimensional pattern of variation in root traits among the 15
coexisting herbaceous species. Moreover, species within the same
phylogenetic clades tended to have similar root trait syndromes. Most of
the root traits exhibited a significant phylogenetic signal. 5. Synthesis.
Our results do not support a one-dimensional root economic spectrum in the
coexisting herbaceous species of temperate grasslands. In contrast, the
pattern of variation in root traits was multi-dimensional. We further
demonstrated that species in different phylogenetic clades possess diverse
root trait syndromes for efficient resource acquisition. Our findings
provide a next step in understanding root functions and plant strategies
in temperate grasslands.