Stoichiometric mechanisms of Dicranopteris dichotoma growth and resistance to nutrient limitation in the Zhuxi watershed in the red soil hilly region of China

Abstract

Little is known about why Dicranopteris dichotoma can succeed in a nutrient-limited environment. This study investigated the stoichiometric mechanisms of D. dichotoma growth and resistance to nutrient limitation in the red soil hilly region of China. We examined D. dichotoma growth, soil nutrients, and stoichiometric variables in the early ecological restoration stage and across the ecological restoration chronosequence. Most of the D. dichotoma growth factors rapidly increased with the arbor-bush-herb mixed plantation and maintained a high level. Soil P was a main factor influencing D. dichotoma growth across the ecological restoration chronosequence, whereas its role is unclear in the early ecological restoration stage. D. dichotoma demanded low C and P and possessed high N and P utilization rates, and N and P distribution was ranked as leaf > root and rhizome > stem. The stoichiometry of D. dichotoma is a relatively weak stoichiometric homeostasis across the whole ecological restoration chronosequence with relatively strong stoichiometric homeostasis in the early ecological restoration stage. Stoichiometry can be used to explore the underlying mechanisms that allow D. dichotoma to succeed to a great extent. D. dichotoma can play an important role in ecological restoration, and microtopography, especially valleys, should be created to trigger the succession of D. dichotoma in the red soil hilly region of China.