Dendroclimatic potential of fokienia trees in the Indochina Peninsula

In order to evaluate the dendroclimatological potential of Fokienia hodginsii growing in montane forests of the Indochina Peninsula, increment core tree-ring samples were collected from 40 individual trees of F. hodginsii from northern Vietnam. Subsequent dendrochronological analysis revealed that ring-width growth was very uneven depending on radial direction with frequent wedging and missing rings. These difficult features hindered the cross-dating of some of the rings in 29 sample trees. However, the r11 trees were not only precisely cross-dated but also revealed significant correlations in ring width among them. The established site chronology based on those 11 trees dates back to AD 1444, resulting in the longest ever made in Southeast Asia. Response analysis of tree-ring width with climate records revealed that hot weather and/or insufficient precipitation during the previous monsoon and current pre-monsoon seasons suppressed radial growth. With isolated but possibly wide natural distribution of Fokienia throughout the northern part of the Indochina Peninsula, Laos, southern China and possibly Myanmar, continued effort toward the development of tree-ring network would lead us to reconstruction of the regional climate.