Coupling of leaf economic and hydraulic traits of desert plants of different life forms in the Ebinur Lake Basin

Abstract

The functional traits of leaves and their internal trade-offs have been the focus of ecologists as a powerful basis for revealing plant physiology and function, and ecological strategies. The consistency of the coupled relationship between leaf economic traits and hydraulic traits among trees, shrubs, and herbs in similar ecological environments has seldom been systematically explored. We explored coupling in desert plants of different life forms and their response to the soil environment in two tree species (Populus euphratica Oliv. and Haloxylon ammodendron (C. A. Mey.) Bunge)), the shrub species (Nitraria tangutorum Bobrov and Halimodendron halodendron (Pall.) Dum. Cours.), and herbaceous species (Alhagi sparsifolia Shap. and Apocynum venetum L.) in the transition zone of the desert in the Ebinur Lake Basin, Xinjiang, China. Leaf and soil samples were collected to determine plant leaf economic traits, hydraulic traits, and soil factors. Regarding leaf economic traits, trees had higher in leaf mass per area and leaf thickness (LT). The leaf nitrogen and phosphorus contents were higher in shurbs than those in trees and herbs. Regarding hydraulic traits, shrubs had higher palisade parenchyma thickness (PT) and vein density (VD), whereas herbs had higher stomatal length (SL), spongy parenchyma thickness (ST), and leaf water potential (Ψ). In herbs, SL, ST, and Ψ had advantages, whereas PT/ST was the lowest. This study revealed an association between leaf economic and hydraulic traits in plants of different life forms in a similar ecological environment and provides a scientific basis for plant conservation strategies and ecosystem services value assessment and use in arid zones.