Keymessage

Results of tree growth–climate relationship analyses and recent variation of climate factors indicated that the Liaotung oak is in a steady development phase on the central Loess Plateau.

Abstract

Liaotung oak (Quercus liaotungensis Koidz.) is a native tree species on the Loess Plateau (LP) of China. However, little is known about the long-term growth variation of Liaotung oak and its response to climate change on the LP. Herein, we clarified the growth response of Liaotung oak to climate change by using dendroclimatological methods. We established a standard tree-ring width (TRW) chronology of Liaotung oak, then conducted static and dynamic tree growth–climate relationship analyses. As shown by static correlation analysis, temperature in late autumn of the previous year, in winter, spring, and early summer of the current year, hydroclimatic factors in late summer and autumn of the previous year, in spring and early summer of current year exerted significant positive influence (P < 0.05) on the radial growth of Liaotung oak. Significant positive influence of winter and spring temperatures on the radial growth of Liaotung oak dramatically decreased since 1990s until 2000s, then increased until 2010s, reaching positively significant level, and subsequently followed by slight decrease. The significant positive influence of spring precipitation was generally stable during the whole moving correlation period; the positive influence of early summer precipitation generally strengthened, reaching significant level (P < 0.05) since 1990s. Influence of drought in late winter and spring of the current year was relatively stable during the whole moving correlation period; the influence of drought in late spring and early summer of the current year steadily increased, reaching positively significant level (P < 0.05) around 2000s, then started decreasing. On the other hand, observation on climate records showed the decrease of temperature in late winter and spring, while the increase of precipitation in spring and early summer, and slight variation of drought index in spring and early summer, after 2010. Based on the above results, conclusion can be made that the Liaotung oak is in a steady development phase under the current climatic conditions on the central Loess Plateau. Our results are of significant importance for the local forest management authorities.