Vegetation and climate in Garhwal Himalaya during Early Holocene: Deoria Tal

Abstract

Pollen analysis of 1.5 m deep profile from the western flank of Deoria Tal (Profile-II), situated in temperate belt of Garhwal Himalaya has unravelled the vegetation and climate of Early Holocene. The vegetation, traced back to about 6000 years and ¹⁴C dated 2710±150 years at 55-65 cm depth, comprised chiefly the Oak dominated forests associated with other broad-leaved taxa such as Betula, Alnus, Rhododendron, Carpinus, Ulmus, etc. Such an arboreal forest composition reflects the warm-temperate humid climate prevalent in the region. A change to cooler climatic conditions is registered between 3500-3600 years B.P., as evidenced by the decline in Oak - the chief component, as well as in other associated broad-leaved elements with a corresponding rise in grasses and sedges. Anthropogenic activities are also recorded during this period, inferred by the first appearance of Cerealia-type pollen and encountered culture pollen. Subsequently, around 1,700 years B.P., the restoration process of Oak forests commenced, thus indicating the amelioration in climatic conditions.