Biomass allocation and leaf stoichiometric characteristics in four desert herbaceous plants during different growth periods in the Gurbantünggüt Desert, China

Abstract

Aims Plant biomass allocation and elemental homeostasis have recently become a focus in ecological studies. Herbaceous plants are a major component of species diversity in desert ecosystems. Study on biomass allocation and leaf stoichiometry with growth will be beneficial to further understanding the survival strategy and functional features of desert herbs. Methods Four dominant species, including two ephemeral plants (Erodium oxyrrhynchum and Hyalea pulchella) and two annals (Agriophyllum squarrosum and Ceratocarpus arenarius), were selected for in situ and multiple- time investigations. Changes in the characteristics of biomass allocation and leaf N-P stoichiometry, as well as their relationships were analyzed. Important findings Root to shoot ratio decreased gradually during the accumulation of plant biomass in all the four species. The allometric relationships between above- and belowground biomass, however, varied among the four species; the allometric scaling exponents in H. pulchella and C. arenarius initially increased and then de- creased, and tended to become stable toward the later period, whereas the allometric scaling exponents in E. oxyrrhynchum and A. squarrosum initially increased and then tended to be isometry in later period. The leaf N and P contents tended to increase in H. pulchella, but declined in other three species with growth, indicating that the leaf N-P stoichiometry of the plants studied changed and showed weak correlations with biomass indices.