Root architecture and ecological adaptation strategies in three shelterbelt plant species in the southern Taklimakan Desert

Abstract

Aims Root architectural properties influence the efficiency and cost of resource exploitation of plants. This paper aims to investigate the root topological properties and ecological adaptation strategies of three plant species which play important roles in wind shelterbelt in the southern Taklimakan Desert of China. Methods We excavated the coarse root systems of three shelterbelt plant species (Tamarix ramosissima, Haloxylon ammodendron, Populus alba var. pyramidalis) at a study site in the southern Taklimakan Desert and analyzed their root architectural properties, including topology, root length, diameter, and scaling relations. Important findings We found differences as well as similarities in the topological structure of root systems among the three plant species. The differences in root structure reflected different adaptation strategies among the plants to soil environment. The root branching order in both T. ramosissima (qa = 0.46, qb = 0.13, TI = 0.84, qa and qb show normed values corresponding to parameters a and b, respectively, TI shows topological index) and H. ammodendron (qa = 0.63, qb = 0.19, TI = 0.90) resembled the herringbone structure; whilst it was dichotomous in P. alba var. pyramidalis (qa = 0.03, qb = 0.02, TI = 0.49). The main root length in the three plant species was all very along. Longer root length could reduce the internal competition of roots for nutrients, so that plants were better cope with the resource-poor sandy soil environment. The Leonardo da Vinci theory is supported in this study with the three plant species.