Tree-Ring Studies in the Eastern Himalayan Region: Prospects and Problems

Tree-ring sampies of different conifer species in various ecological settings from subtropical to temperate regions of the Eastern Himalayan region have been evaluated for their potential for dendroc1imatic reconstructions. Most of these tree species have cross-datable growth rings except Taxus baccata and Tsuga dumosa where series of micro-rings and lack of variation in these suppressed zones make cross-dating difficult. Tree-ring chronologies have been established from Abies densa and Larix griffithiana , the only deciduous conifer species in the Himalayas. Tree growth-climate relationships reveal that temperature is a determinant factor for the growth of trees at high elevations. Abies densa in the western part of Arunachal Pradesh shows a negative response to the July-September temperature whereas Larix griffithiana shows a positive response to the May temperature.