Process-based modeling analyses of Sabina przewalskii growth response to climate factors around the northeastern Qaidam Basin

Yongxiang Zhang,Yan Xu,Martin Wilmking,Xuemei Shao

doi:10.1007/s11434-011-4456-5

Abstract

Sabina przewalskii is the longest living endemic tree species in the northeastern Tibetan Plateau, and has been widely employed in tree ring based climate research in China. However, most dendroclimatic reconstructions have been primarily based on empirical relationships between tree growth and climate factors identified by statistical assessment. To date, the physiological relationships between tree growth and their limiting climate factors have not been properly assessed. Here, we simulated the physiological response of Sabina przewalskii tree growth to major limiting climate factors based on the Vaganov-Shashkin (VS) model. The VS modeled results validated the relationships between tree ring and climate factors constructed by statistical models, both approaches suggesting that precipitation during the early growing season, especially in May and June, has significant effect on tree growth, while temperature mainly affects tree growth by warming-induced drought and by extending the growing season. Under current and projected climate scenarios, our modeling results predict an increase in radial growth of Sabina przewalskii around the Qaidam Basin, with the potential outcome that regional forests will increase their capacity to sequester carbon.

Highlights

Sabina przewalskii is the longest living endemic tree species in the northeastern Tibetan Plateau, and has been widely employed in tree ring based climate research in China
As temperatures have increased in many parts of the Earth during the last century, a phenomenon called “divergence” between tree growth and climate factors has been reported from the Northern hemisphere circumpolar area and from mountain area in the mid-latitudes of the Northern Hemisphere
In China, the VS model successfully simulates the growth of Pinus tabulaeformis from Helan Mts and Pinus armandii from Huashan [20–22], and was an obvious choice for the simulation of radial tree growth in our current study species

Summary

Introduction

Sabina przewalskii is the longest living endemic tree species in the northeastern Tibetan Plateau, and has been widely employed in tree ring based climate research in China. We simulated the physiological response of Sabina przewalskii tree growth to major limiting climate factors based on the Vaganov-Shashkin (VS) model. Tween tree ring based reconstruction and measured data [8–10], the divergence of tree growth and their main limiting climate factors [11,12] and the divergent growth responses of trees within sites [13,14]. All of these divergences indicate that the statistically approximated linear relationship might not universally apply between tree growth and their limiting climate factors. (5) The model simulates variations in growth rate and tree ring structure resulting from current climatic changes (within the season). In China, the VS model successfully simulates the growth of Pinus tabulaeformis from Helan Mts and Pinus armandii from Huashan [20–22], and was an obvious choice for the simulation of radial tree growth in our current study species

Methods

Results

Discussion

Conclusion