Late Holocene fire and precipitation history of the Kashmir Himalaya: Inferences from black carbon in lake sediments

Abstract

Throughout the human history, fire, climate, and human advancement had a very complicated relationship. Scientists have explored this relationship using different proxies such as black carbon, polycyclic aromatic hydrocarbons, and charcoal. In this study, black carbon (BC) concentrations and its isotopic compositions (δ13CBC) in a sediment core from the Wular Lake, Kashmir (India) were measured to understand the interactions of fire and human development in the Kashmir Himalaya during the late Holocene. As revealed through radiocarbon dating, the sediment core covered the time span from 3752 to 306 Cal years BP. Two major climate phases in the region were identified based on the relationship between mean annual precipitation and δ13CBC. The first phase, from 3752 to 1500 Cal year BP, was characterised by low mean annual precipitation (dry climate), which transitioned into a wetter phase with higher mean annual precipitation after 1500 Cal year BP until 306 Cal year BP. Within the dry phase, a phase of extreme dryness and minimum precipitation around ∼2500 Cal years BP was observed. The variability in BC concentrations in the sediments revealed dynamic fire history in the Kashmir Himalaya with occurrences of high fire events around 3000 Cal years BP, which gradually declined until 1500 Cal year BP then increase again. Our results, in combination with available studies from the region, suggested that forest fires in the Kashmir Himalaya were dominantly human-driven than due to large scale climate change.