Functional Traits of a Rainforest Vascular Epiphyte Community: Trait Covariation and Indications for Host Specificity

Diversity

Wolfgang Wanek¹  Gerhard Zotz²  Katrin Wagner² 

[1] Department of Microbiology and Ecosystem Science, Center of Microbiology and Environmental Systems Science, University of Vienna, A-1090 Vienna, Austria;Institute for Biology and Environmental Sciences, Functional Ecology, Carl von Ossietzky University Oldenburg, Box 2503, D-26111 Oldenburg, Germany;

关键词: host preference;    leaf carbon isotope ratio;    leaf dry matter content;    leaf thickness;    leaf nitrogen concentration;    leaf nitrogen isotope ratio;   

DOI  :  10.3390/d13020097

来源: DOAJ

【 摘 要 】

Trait matching between interacting species may foster diversity. Thus, high epiphyte diversity in tropical forests may be partly due to the high diversity of trees and some degree of host specificity. However, possible trait matching between epiphyte and host is basically unexplored. Since the epiphytic habitat poses particular challenges to plants, their trait correlations should differ from terrestrial plants, but to what extent is unclear as epiphytes are underrepresented or missing in the large trait databases. We quantified 28 traits of 99 species of vascular epiphytes in a lowland forest in Panama that were related to plant size, leaf, stem, and root morphology; photosynthetic mode; and nutrient concentrations. We analyzed trait covariation, community weighted means, and functional diversity for assemblages on stems and in crowns of four tree species. We found intriguing differences between epiphytes and terrestrial plants regarding trait covariation in trait relations between plant maximal height, stem specific density, specific root length, and root tissue den-sity, i.e., stem and root economic spectra. Regarding host specificity, we found strong evidence for environmental filtering of epiphyte traits, but only in tree crowns. On stems, community weighted means differed in only one case, whereas > 2/3 of all traits differed in tree crowns. Although we were only partly able to interpret these differences in the light of tree trait differences, these findings mark an important step towards a functional understanding of epiphyte host specificity.

【 授权许可】

Unknown