Abstract
In this study we analyzed signatures of prolonged inundation on tree rings aiming at developing an estimation method of flood water level from tree-ring records.
The sample tree of this study is an enoki hackberry (Celtis sinensis) at the west shore of Lake Biwa, Japan. This tree was inundated for 23 days from Sep. 9 to Oct. 1 in the 1896 extreme flood. It was felled in July of 2002 and we took four disks from different heights of the trunk.
As a result, a flood ring with abnormally thin alignment of earlywood vessels of relatively small diameter in the pore zone was found in the 1897 ring. This feature is the most significant at the lowest position of the trunk. The measured ring-width series indicated abrupt drop in growth in 1897 and subsequent growth suppression for several years.
