Stubble burning and forest fire along the Himalayas can trigger melting of the already receding Gangotri glacier, a primary source of water for the Ganges river in India's Uttarakhand state, our New Delhi correspondent reports citing a study.

Scientists from the Wadia Institute of Himalayan Geology (WIHG), an autonomous research institute under the Indian Ministry of Science and Technology, conducted the study at Chirbasa station near the glacier in 2016.

Black carbon concentration in the region increases by 400 times during summer and can trigger glacial melt because of the light-absorbing nature of black carbon, the study says.

By probing the occasional high values of black carbon extricated from the area, the scientists found that the seasonal cycle of increase was significantly influenced by the emissions resulting from stubble burning in western part of the country, forest fires along the Himalayan slopes in summer and to some extent, by the contribution from long-range transport of pollutants in winter depending on the prevailing meteorological conditions.

The research led by Dr PS Negi was published in the scientific journal, "Atmospheric Environment."

"The Equivalent Black Carbon aerosols contribute significantly towards global warming due to its light-absorbing nature," the study says. "Their presence in the eco-sensitive zone such as the Himalayan glacier valleys is a matter of serious concern and needs to be meticulously monitored."

Smoke emanating from stubble burning in Punjab and Haryana is one of the key causes of severe air pollution in Delhi that doctors say triggers respiratory problems.