NEW DELHI, Apr 28 (Xinhua)-- Glaciers feeding the Ganga, Yamuna,Indus and the Brahmaputra rivers may be wiped out in 40 years, impacting the economic, cultural and spiritual life of India, scientists have warned.

    The warning bells were sounded in the first report on melting glaciers and their impact by Sagarmatha -- the Snow and Glacier Aspects of Water Resources Management in the Himalaya -- presentedin New Delhi on late Tuesday, according to an Indo-Asian News Service report on Wednesday.

    Sagarmatha, commissioned by Britain's Department for International Development (DFID), gives a decade-by-decade analysis for Indian rivers over the next 100 years.

    The study warns that global warming will result in increased glacial waters in the next 40 years -and then the shortfall of theprecious resource will begin.

    It urges timely water management activities.

    According to the study, the upper Indus over the first few decades will have plus 14 percent to plus 90 percent increase, after which there will be a drastic fall to as low as 30-90 percent below the baseline level by decade.

    The Kaligandaki basin in the east, however, contrasts in behaviour. The decadal mean flow shows an increase throughout the next 100 years; the most extreme temperature scenario attaining a peak mean flow of between plus 30 percent and plus 90 percent.

    For the Ganga, near its headwaters in Uttarkashi, the flow is predicted to peak at plus 25 to plus 33 percent of baseline level within the first two decades and then recede to as low as minus 50percent of the baseline by the sixth decade. Enditem