Pollen proxy records of Holocene vegetation and climate change from Mansar Lake, Jammu region, India

摘要

Pollen analysis of a 30 m deep sediment core from Mansar Lake has revealed that around 9000-8000 yrs BP, the mixed chirpine-oak forests dominated by Pinus cf. roxburghii (chirpine) existed in the Jammu region under a cool and dry climate. Later, they were succeeded by mixed oak-chirpine forests between 8000 and 7000 yrs BP with the expansion of oak (Quercus cf. incana) and other broad-leaved taxa in response to initiation of a warm and humid climate. Between 7000 and 3000 yrs BP, the cool and dry climate prevailed again as inferred by the reduction in broad-leaved taxa and a simultaneous improvement in the conifers, especially Pinus cf. roxburghii. However, a brief spell of pluvial activity is witnessed between 5500 and 4250 yrs BP, as envisaged by the presence of sandy deposits. Around 3000 to 750 yrs BP, expansion of oak and most of the broad-leaved taxa suggests the prevalence of a warm and more humid climate. From 750 yrs BP to the Present the climate deteriorated, as reflected by the replacement of mixed oak-chirpine forests by mixed chirpine-oak forests in the region. There has been an acceleration of human activities during the last millennium as indicated by the record of culture pollen taxa.