Abstract: To understand the growth responses of different tree species to climatic factors in the eastern Qilian Mountains, we developed tree-ring width chronologies from two dominant tree species (Picea crassifolia and Juniperus przewalskii). The correlation coefficients between chronologies and climatic factors were calculated at 24 time scales. According to the parameters of chronologies, the residual chronology of P. crassifoliahad higher quality than the standard chronology, but the case was oppoiste forJ. przewalskii. The responses of J. przewalskii to temperature factors were stronger than that of P. crassifolia, which showed negative correlation with mean temperature from the previous June-July, the previous September and the current May-August. The responses of P. crassifolia to precipitation factors were stronger than that ofJ. przewalskii, which were positively correlated with total precipitation from the previous September and the current July-August. The radial growth of both species suffered from drought stress. In the context of global warming and intensified drought stress, enhanced protection and management should be carried out.

Key words: black soil, vegetation type, soil profile, soil organic carbon, carbon storage.