Altitudinal treeline dynamics of Himalayan pine in western Himalaya, India

作者：Yadava, Akhilesh K.; Sharma, Yogesh K.; Dubey, Bhasha; Singh, Jayendra; Singh, Vikram; Bhutiyani, Mahendra R.; Yadav, Ram R.; Misra, Krishna G.

来源：Quaternary International, 2017, 444: 44-52.

DOI：10.1016/j.quaint.2016.07.032

• Himalayan pine
• Treeline dynamics
• Climate change
• Western Himalaya
• India

The instrumental weather records from the western Himalayan region for the past century show an increase in annual mean atmospheric temperature with winters warming at a faster rate. The vegetation of the upper ecotonal zones, already on the climatic threshold is sensitive to any such change in climate variable most limiting the growth. To investigate the impact of climate change on treeline dynamics of Himalayan pine (Pinus wallichiana A. B. Jackson), we investigated its recruitment pattern in 12 treeline sites of different ecological settings widely distributed in monsoon and monsoon-shadow zones in the western Himalaya, India. The study explicitly revealed that Himalayan pine treeline has shifted towards the upper elevation in the investigated sites, but with varying rate (11-54 m/10 yrs) largely due to site-specific microclimatic and biotic factors. Tree-ring-width chronologies of Himalayan pine prepared from two upper forest border sites, one each in monsoon and monsoon-shadow zone, respectively revealed that winter and early spring season mean temperature has direct relationship with the radial growth of trees. This indicates that the photosynthetic assimilates during winter and early spring seasons significantly influence the ensuing year's tree growth. The sensitivity of Himalayan pine to climate change revealed in this study indicates that the projected climate change under the background influence of greenhouse gases could have serious implications on biodiversity of upper elevations in the western Himalaya.

• 出版日期2017-7-15