Dendrochronological Investigations in Thailand

Some of the first tree-ring chronologies from mainland Southeast Asia have been developed from Thailand, and a significant link between climate and tree growth has been suggested. Four chronologies from two species of pine (Pinus kesiya Royle ex Gordon and Pinus merkusii Jungh. & de Vriese) from northeastern, lower northern and northwestern Thailand have been constructed: three from P. kesiya and one from P. merkusii. A second P. merkusii chronology is being developed from samples from northwestern Thailand. Preliminary climate modelling demonstrates significant relationships for tree growth with both temperature and precipitation for both species, A significant, direct relationship is revealed with temperature at the beginning of the wet season for Pinus merkusii from Thung Salaeng Luang National Park, along with an inverse relationship with precipitation for the same period. It is also suggested that the month of November (the transitional month from wet to dry season) during the year of growth is most important for Pinus kesiya from Nam Nao National Park, based on significant, direct relationships with both temperature and precipitation. The dendrochronological potential of another species, the long-lived Podocarpus neriifolius, is also discussed.