Growth response of Pinus tabulaeformis to climate along an elevation gradient in the eastern Qinling Mountains, central China

摘要

Tree growth response to climate is not well understood in the eastern Qinling Mountains of central China, an East Asian monsoon dominated region. In this study, we developed 4 robust tree-ring width chronologies using Chinese pine Pinus tabulaeformis along an elevation gradient. The 4 chronologies were significantly correlated with each other. Through standard correlation function analysis, we found that each of the 4 chronologies correlated negatively with temperature, especially with maximum temperature in May and June, and positively with precipitation from prior December to current May. Principal component analysis and composite analysis of years when extremely narrow rings were common to all 4 chronologies confirmed this relationship. However, precipitation in the current September and October was positively correlated to tree growth at lower sites and negatively at higher ones, and temperature stress effects increased with elevation. The findings will help understand the growth response of this tree species to climate change in the southern part of its range, and provide critical information for future climate reconstructions using this tree species in humid or semi-humid regions.