Age dependent growth response of Cedrus deodara to climate change in temperate zone of Western Himalaya

The recent warming in the mountain regions affect forest productivity in terms of tree growth, especially in the Himalayan region. However, the effects of climate change on the response of radial growth of different age-class trees in the Himalayan region remains unclear. The sensitivity of different age-class trees can differ from younger to old age-class tree growth which create uncertainty in tree-ring calibration against the climatic parameters. In the present study, we assessed the effect of climate change on the radial growth of Cedrus deodara (cedar) from two different age classes; young (age 100 years) in lower temperate zone of Indian Western Himalaya for the period 1950-2015 CE. We modelled basal area increment (BAI) using the Generalized additive model (GAM) which predicted the observed pattern of BAI as a function of year and random effect of tree. The trend of old age stand BAI increased significantly by 0.13 cm2/year whereas it significantly declined by -0.27 cm2/year for young deodar stand. However, from 1990 CE both age classes showed significant decline (p