Text by Lauri Laanisto
This paper was actually published already in the autumn of 2014, but as according to the page numbers, it´s a paper from 2015, there will be a blog post..
Leaf economic spectrum is one of the two main topics Ülo is constantly dealing with (the other being VOCs). But who of us hasn´t been charmed by the glamour of trait-based vegetation science…
This review paper points out how the intra-specific variability (trait variability within one species) can really blur things up in the trait-based ecology and physiology, based on data of only one species – Quercus ilex. Even some traits that are considered relatively conservative (or just numb) tend to have within-species variability up to almost an order of magnitude. Ülo suggests that “This study argues that the within-species economics spectrum needs to be considered in regional- to biome-level analyses.”, but I´m not sure if that will be enough. Let´s see. Hopefully there will be more about the patterns of intra-specific trait variability in this blog soon. I´m working on it…
Full citation: Niinemets, Ü. (2015). Is there a species spectrum within the world‐wide leaf economics spectrum? Major variations in leaf functional traits in the Mediterranean sclerophyll Quercus ilex. New Phytologist, 205(1), 79-96. (link to full text)
The leaf economics spectrum is a general concept describing coordinated variation in foliage structural, chemical and physiological traits across resource gradients. Yet, within this concept, the role of within-species variation, including ecotypic and plastic variation components, has been largely neglected. This study hypothesized that there is a within-species economics spectrum within the general spectrum in the evergreen sclerophyll Quercus ilex which dominates low resource ecosystems over an exceptionally wide range. An extensive database of foliage traits covering the full species range was constructed, and improved filtering algorithms were developed. Standardized data filtering was deemed absolutely essential as additional variation sources can result in trait variation of 10–300%, blurring the broad relationships. Strong trait variation, c. two-fold for most traits to up to almost an order of magnitude, was uncovered. Although the Q. ilex spectrum is part of the general spectrum, within-species trait and climatic relationships in this species partly differed from the overall spectrum. Contrary to world-wide trends, Q. ilex does not necessarily have a low nitrogen content per mass and can increase photosynthetic capacity with increasing foliage robustness. This study argues that the within-species economics spectrum needs to be considered in regional- to biome-level analyses.