Wood ultrastructure of ancient buried logs of Fitzroya cupressoides.

摘要

The anatomy and ultrastructure of subfossil wood of Fitzroya cupressoides from the late Pleistocene (>50 000 14C years before present) were compared with those of extant F. cupressoides trees from southern Chile, using light microscopy (polarized light and fluorescence), scanning electron microscopy coupled with an energy dispersive X-ray spectroscopy system, and transmission electron microscopy. The ancient wood showed an unchanged gross wood structure, loss of cell wall birefringence, loss of lignin autofluorescence, and a loss of the original microfibrillar pattern. The energy dispersive X-ray spectroscopy analysis indicated higher than normal contents of S, Cl, and Na in subfossil wood. Ultrastructural modifications in the cell wall of the subfossil wood could have important implications for further studies involving isotopic and wood anatomical measurements of ancient wood..