Plant functional traits

The whole-plant economics spectrum (PES) refers to the trade-offs among
the many plant functional traits that are commonly used as indicators of
major adaptive strategies, thereby providing insights into plant
distributions, ecosystem processes, and evolution. However, there are few
studies of what may be called the whole-plant economic spectrum (PES) that
integrates bark, wood, and leaf functional traits for different
leaf-types and growth habits (evergreen versus deciduous species). To
address this gap in our knowledge, 6 bark traits, 7 wood traits
(including mechanical support and nutrient transport characteristics), and
12 leaf traits (including chemical, structural, and physiological
characteristics) of 59 representative subtropical woody species were
examined using principal component analysis (PCA) to determine PES
strategies. The economics spectra of bark (BES), wood (WES), and leaves
(LES), and the entire PES indicated that major traits represent resource
acquisition strategies and conservation strategies clustering on the
opposite ends of the PCA axis. A significant correlation was observed
among the 25 functional traits. The data indicated that N and P
nutrient levels were at the hub of BES, WES,
LES, and PES interrelationships. Evergreen and deciduous species had
different WES and LES, and thus PES resource acquisition
strategies. With the exception of the BES, evergreen species clustered on
the conservative side, whereas deciduous species clustered on the
acquisitive side. The PES presented here informs our
understanding of whole-plant responses to environmental differences,
particularly regarding the role of N and P traits
at the whole-plant level. It also reveals and further
supports the notion that evergreen and deciduous species respectively
manifest conservative and acquisitive strategies, further informing our
understanding of species biodiversity maintenance.