[Climatic signals recorded by Qinghai spruce tree-ring density in the western part of Qilian Mountains, China].

Abstract

Dendroclimatology is one of the important methods for studying climate changes in the past. Previous studies showed that tree-ring density is an important proxy for temperature in the growing season. In this study, we established 132-135 years chronologies of tree-ring maximum density, the minimum density, the latewood and the earlywood average density of Picea crassifolia at the western Qilian Mountains. We compared the climatic signal and its seasonal best combination of different tree-ring density chronologies, and evaluated their potential values as climate proxies. The responses of tree-ring latewood average density and the earlywood average density to climate signals during the growing season were much lower than that of tree-ring maximum and the minimum den-sity. The tree-ring earlywood average density and the minimum density had a strong relationship with the Palmer drought index, indicating that the earlywood average density and the minimum tree-ring density had the potential as substitute indicators for drought.