Teak Tree-Ring Cellulose delta C-13, delta O-18, and Tree-Ring Width from Northwestern Thailand Capture Different Aspects of Asian Monsoon Variability

摘要

The inter-annual variability in tree-ring cellulose delta C-13 (delta C-13(TR), delta O-18(TR)), and tree-ring chronology in teak (TRW) (Tectona grandis L.f.) trees from Northwestern Thailand during 1901-2009 AD was performed. The delta C-13(TR) and delta O-18(TR) have a positive correlation, significant at r = 0.400, p < 0.0001, and both of the stable isotopes were not significantly related to the TRW. The TRW is related to rainfall in the first half of the rainy season and has a strong relationship with the relative humidity. The delta O-18(TR) captured moisture well throughout the rainy season, and the delta C-13(TR) had a strong correlation with rainfall in the second half of the rainy season and had a high correlation with cloud fraction and vapor pressure. The delta C-13(TR) and delta O-18(TR) were associated with the stomata conductance response, but had no effect on photosynthesis. The three indices of the teak annual ring respond well to the variability in the Asian monsoon, and give us a better understanding of both the hydrological cycle and the factors that contribute to the growing of tropical broadleaf trees under changing climates.