Global climate change is a burning issue in the present world. It has been found that the rate of warming in Hindu-kush Himalayas (Eastern Himalayan region) is higher than average global warming rate. If average temperature increases as predicted all aspects of human and natural life will be affected. The high altitude-species will face threaten by endangerment and extinction.

The impact of climate change on plant species can be observed through the shifting in the vegetation zone, change in phenological events, advancing of tree-line, etc. Phenological observation provide one of the best biological indicators of climate change and such studies is almost negligible in Eastern Himalayan region, so there is need of such studies in this region for the conservation planning. The climate change studies are possible through the establishment of long term observation sites. Therefore the current work is designed to establish site for observing phenological events, as well as shifting of vegetation zone and biological invasion in long term.

Rhododendrons are chosen as indicator species for this study as they act as one of the keystone species, supporting a wide variety of habitat, which is vital to maintain pollinator populations and they function as matrix species in many areas.