Potential Trees Species of North-East India for Dendroclimatological Studies

Abstract

Many tropical trees show distinct annual ring formation as in temperate conifers, and the growth of these annual rings is used as bio-indicators of environmental changes. Dendroclimatology is the science dealing with the reconstruction of a history of past climate through dendrochronological (tree ring) analysis and assessing the effect of climatic change on tree growth. Trees are living natural archives and their growth is largely impacted by various climatic and non-climatic events occurring in the surrounding environments. In Northeast India, several conifers and broad-leaf tree species such as Abies densa, Larix griffithii, Pinus merkusii, Pinus kesiya, Pinus wallichiana, Quercus serrata, Toona ciliata and Tectona grandis have been used for tree ring-based studies. Dendrochronological studies mainly focused on the reconstruction of climate history, climate-tree growth relationship, river flow history reconstruction, inter-annual density fluctuation, and for development of climate proxies. Among these, the oldest tree ring chronology of Abies densa of 490 years (1504 to 1994) was reported from Yumthang of Sikkim. Whereas the youngest chronology of Toona ciliata of 35 years (1984 to 2018) was from Chandel district of Manipur. The knowledge derived from the detailed study of these species will help forest managers and conservationists to manage the forest in a changing environment. This paper presented dendrochronological information of different trees of northeast India based on the published literature and their possible impact on climate reconstruction through dendroclimatology. However, further potential tree species forming tree rings need to be worked out for possible climate mitigation measures of tropical trees in northeast India.