Coordination of economics spectra in leaf, stem and root within the genus Artemisia along a large environmental gradient in China

Aim: The plant economics spectrum provides a fundamental framework for
understanding functional trait variation along environmental gradients.
However, it is unclear whether there is a general whole-plant economics
spectrum across organs at the finer taxonomic scale (e.g. within genera),
and if there is, which factors affect the trait coordination of the
different organs. Here, we examined whether resource economics spectra of
different organs (i.e. leaf, stem and root) can be integrated at the
whole-plant level within a single genus, and how environment,
intraspecific variation and taxonomic scale shape the whole-plant
spectrum. Location: China. Time period: 2018. Major taxa studied:
Artemisia. Results: Pairwise trait correlations and the trade-off patterns
along the resource economic axis were consistent at both organ and
whole-plant levels. Environmental gradients did not strongly affect the
correlations among leaf, stem and root economics spectra, i.e. the
intraspecific variation weakened but did not mask this coordination.
Taxonomic scale did not affect the degree of trait coordination as the
genus-wide whole-plant economics spectrum also emerged within each of the
three subgenera. Main conclusions: Our results support the hypothesis that
the coordination of economics spectra across organs forms a whole-plant
economics spectrum representing “fast-slow” resource management strategy,
which is robust to recent evolution (genotypic variation, even for species
within a single genus) and present-day environmental variation. Further
studies should elucidate in which circumstances or phylogenetic branches
the coordinated pattern found for Artemisia is representative of other
widely distributed genera.