4.7 Article

Are leaf, stem and hydraulic traits good predictors of individual tree growth?

期刊

FUNCTIONAL ECOLOGY
卷 35, 期 11, 页码 2435-2447

出版社

WILEY
DOI: 10.1111/1365-2435.13906

关键词

basal area increment; functional trait; growth efficiency; hydraulics; intraspecific variability; leaf economic spectrum; water availability

类别

资金

  1. Ministerio de Ciencia e Innovacion [CGL2013-46808-R, CGL2017-89149-C2]
  2. MINECO
  3. ICREA Academia

向作者/读者索取更多资源

The study found that trait-growth relationships in trees under Mediterranean climate are generally weak, with tree growth performance mainly correlated with leaf and hydraulic traits. Climate effects on growth are indirectly mediated by traits, stand structure, and tree basal area. This suggests that maintaining functionality over extended periods of time may be more important than maximum gas exchange or hydraulic capacity for achieving high radial growth under Mediterranean climates.
A major foundation of trait-based ecology is that traits have an impact on individual performance. However, trait-growth relationships have not been extensively assessed in trees, especially outside tropical ecosystems. In addition, measuring traits directly related to physiological processes remains difficult and the differences between inter- and intraspecific relationships are seldom explored. Here, we use individual-level data on a set of hydraulic, leaf and stem traits to assess their ability to predict basal area increment (BAI) and growth efficiency (BAI per unit of tree leaf area, GE) among and within species for six dominant tree species along a water availability gradient under Mediterranean climate (Catalonia, NE Spain). Measured traits include: leaf mass per area (LMA), leaf nitrogen concentration (N), leaf C isotopic composition (delta C-13), the leaf water potential at turgor loss (P-tlp), stem wood density (WD) and branch-level estimates of the Huber value (Hv), sapwood- and leaf-specific hydraulic conductivity (K-S and K-L) and resistance to xylem embolism (P-50). Trait-growth associations were generally weak, particularly for BAI and within species. High values of both growth metrics were associated with 'conservative' leaf and hydraulic traits. In particular, BAI was negatively associated with K-L (and wood density), while GE increased with LMA, allocation to sapwood relative to leaves (Hv) and resistance to xylem embolism (P-50). Climate effects on BAI and GE were indirectly mediated by changes in traits, stand structure and tree basal area. Overall, these results suggest that maintaining functionality over extended periods of time may be more important than maximum gas exchange or hydraulic capacity to achieve high radial growth under Mediterranean climates. Our study reveals that widely used 'functional traits' may be poor predictors of tree growth variability along environmental gradients. Moreover, trait effects (when present) do not necessarily conform to simple hypotheses based on our understanding of organ-level processes. An improved understanding of trait coordination along common axes of variation together with a revaluation of the variables that better reflect whole-tree performance can greatly improve our understanding of trait-growth relationships. A free Plain Language Summary can be found within the Supporting Information of this article.

作者

我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。

评论

主要评分

4.7
评分不足

次要评分

新颖性
-
重要性
-
科学严谨性
-
评价这篇论文

推荐

暂无数据
暂无数据