Stable Isotopes in trees
Species and Site Selection
The ground rule in choosing sites for trees isotope work is for the trees to be properly cross-dated. Reliable cross-dating is critical is wood sampled from several trees are to be pooled prior to analysis, otherwise the wood from one year would be mixed with that of another year, resulting in noisy, uninterpretable signals .
Furthermore, the choice of site and specimens should be guided by knowledge of isotope theory and the ecophysiology of trees. For instance, if the goal is to reconstruct changes in summer temperature and sunshine using stable carbon isotopes, it would be better to choose sites where the trees are unlikely to have been water-stressed and deep-rooted specimens . There is one important exception in choosing tree specimens, and to some extent sites, that are predicted to be sensitive to one particular climate variable . If the calibration to instrumental data is made on the "best available" specimens but this perfect calibration is then applied to fossil trees whose growth conditions are unknown, the interpretation may be biased .
- McCarroll, D., & Loader, N. J. (2004). Stable isotopes in tree rings. Quaternary Science Reviews, 23(7-8), 771-801. doi:10.1016/j.quascirev.2003.06.017
- McCarroll, D. and N.J. Loader, Isotopes in tree rings, in Isotopes in palaeoenvironmental research, M.J. Leng, Editor. 2006, Springer: The Netherlands. p. 67-116.