Meaningful traits for grouping plant species across arid ecosystems

• Published in: Journal of plant research 2016-05, Vol.129 (3), p.449-461
• Main Authors: Bär Lamas, Marlene Ivonne, Carrera, A. L., Bertiller, M. B.
• Format: Article
• Language: English
• Subjects: Arid zones; Biomass; Biomedical and Life Sciences; Desert Climate; Dominant species; Ecological function; Ecosystem; Ecosystem biology; Ecosystems; Environmental stress; Flowers & plants; Geography; Grasses; Herbivory; Leaves; Life Sciences; Nitrogen - analysis; Phenols; Phenols - analysis; Plant Biochemistry; Plant Development; Plant Ecology; Plant growth; Plant Leaves - anatomy & histology; Plant Leaves - growth & development; Plant Physiology; Plant Sciences; Plant species; Plants; Plants - anatomy & histology; Plants - classification; Quantitative Trait, Heritable; Regular Paper; Shrubs; Solubility; Species Specificity
• ISSN: 0918-9440; 1618-0860
• DOI: 10.1007/s10265-016-0803-6

Grouping species may provide some degree of simplification to understand the ecological function of plants on key ecosystem processes. We asked whether groups of plant species based on morpho-chemical traits associated with plant persistence and stress/disturbance resistance reflect dominant plant growth forms in arid ecosystems. We selected twelve sites across an aridity gradient in northern Patagonia. At each site, we identified modal size plants of each dominant species and assessed specific leaf area (SLA), plant height, seed mass, N and soluble phenol concentration in green and senesced leaves at each plant. Plant species were grouped according with plant growth forms (perennial grasses, evergreen shrubs and deciduous shrubs) and plant morphological and/or chemical traits using cluster analysis. We calculated mean values of each plant trait for each species group and plant growth form. Plant growth forms significantly differed among them in most of the morpho-chemical traits. Evergreen shrubs were tall plants with the highest seed mass and soluble phenols in leaves, deciduous shrubs were also tall plants with high SLA and the highest N in leaves, and perennial grasses were short plants with high SLA and low concentration of N and soluble phenols in leaves. Grouping species by the combination of morpho-chemical traits yielded 4 groups in which species from one growth form prevailed. These species groups differed in soluble phenol concentration in senesced leaves and plant height. These traits were highly correlated. We concluded that (1) plant height is a relevant synthetic variable, (2) growth forms adequately summarize ecological strategies of species in arid ecosystems, and (3) the inclusion of plant morphological and chemical traits related to defenses against environmental stresses and herbivory enhanced the potential of species grouping, particularly within shrubby growth forms.