Holocene palaeoclimate and glacier fluctuations within Baspa Valley, Kinnaur, Himachal Pradesh

摘要

Present study is an attempt to understand the tree line shift in relation to glacier fluctuations during Holocene based on the exploratory palynological studies from a 1.3 m deep sediment profile located at 3,100 meters above mean sea level (mamsl), Rukti valley, Kinnaur, Himachal Pradesh. The study reveals that during the early to middle Holocene, tree line taxa viz. Betula and Juniperus were well characterized in the site of investigation evident by higher percentage of their pollen grains in subsurface sediments than those recorded during the late Holocene. This variation in distribution of these taxa suggests that till middle Holocene tree line was close to the study site (3,100 mamsl) i.e. at lower altitude than its present day distribution between 3,800 to 3,900 mamsl. Accordingly, the glacier snout might also be at lower elevations (～3,500 mamsl) than its present day location at altitude (～4,300 mamsl).