Global Ecology and Conservation (Dec 2021)
C:N:P stoichiometric characteristics of the soil–vegetation system of three rare tree species growing on Mount Fanjing in Southwest China
Abstract
The aim of this study was to understand the C:N:P stoichiometry of three rare tree species that grow at different elevations of Mount Fanjing Nature Reserve in Guizhou Province, China. We analyzed the C, N and P stoichiometry of new stems, leaves and soil of two coniferous species, Abies fanjingshanensis and Taxus chinensis var. mairei, and of the hardwood tree Davidia involucrata. The total-C, total-N, hydrolyzed-N and available-P contents of the forest soils were higher at higher altitudes, with median values for A. fanjingshanensis forest soil > T. chinensis var. mairei soil > D. involucrata soil. The C:N, C:P and N:P ratios of soil in A. fanjingshanensis stands were the largest, and significantly higher than those of soils in T. chinensis var. mairei and D. involucrata stands. The C content of stems and leaves of the coniferous tree species was higher than that of the hardwood tree species. The N:P ratio of stems and leaves ranged from 0.06 to 0.22. The total-C, total-P and total-N of soil explained 37.5%, 11.0% and 8.0%, respectively, of the variance in C, N and P content and stoichiometry of plant stems and leaves. The total-C content of soil was positively correlated with the C and P contents of plant leaves, the C:N ratio and the C content of plant stems. Except for the total-C content of the soil–vegetation system, in general, the stoichiometric characteristics of N and P of soils and plants in the study area were not significantly correlated. Correlations between C, N, and P nutrients and the stoichiometric characteristics of the soil–vegetation system of the different forest types and environments varied. In the reserve environment, the growth of T. chinensis var. mairei and D. involucrata was restricted by N limitation in the soil. Our findings could provide basic data for the management and protection of rare plants growing on Mount Fanjing.
