Open boats on Shennong Stream, in the Three Gorges off the Yangtze River in China. Glaciers in the Yangtze source area, central to the Qinghai-Tibet plateau in south-western China, have receded 196 square kilometres over the past 40 years.
Glaciers that serve as water sources to one of the most ecologically diverse alpine communities on earth are melting at an alarming rate, according to a recent report.
A three-year study, to be used by the China Geological Survey Institute, shows that glaciers in the Yangtze source area, central to the Qinghai-Tibet plateau in south-western China, have receded 196 square kilometres over the past 40 years.
Glaciers at the headwaters of the Yangtze, China's longest river, now cover 1,051 square kilometres compared to 1,247 square kilometres in 1971, a loss of nearly a billion cubic metres of water, while the tongue of the Yuzhu glacier, the highest in the Kunlun Mountains fell by 1,500 metres over the same period.
Melting glacier water will replenish rivers in the short term, but as the resource diminishes drought will dominate the river reaches in the long term. Several major rivers including the Yangtze, Mekong and Indus begin their journeys to the sea from the Tibetan Plateau Steppe, one of the largest land-based wilderness areas left in the world.
“Once destroyed it will be extremely difficult to restore the high-altitude ecosystems,” said Dr Li Lin, head of Conservation Strategies for WWF-China. “If industrialized and developing countries do not focus their efforts on cutting emissions, some of this land will be lost forever and local populations will be displaced.”
Glacier retreat has become a major environmental issue in Tibet, particularly in the Chang Tang region of northern Tibet. The glacier melting poses severe threats to local nomads’ livelihoods and the local economy.
The most common impact is that lakes are increasing due to glacier melting and some of the best pastures are submerged. Meanwhile small glaciers are disappearing due to the speed of glacier melting and drinking water has become a major issue.
“This problem should convince governments to adopt a ‘mountain-to-sea’ approach to manage their rivers, the so-called integrated river basin management, and to ratify the UN Water Convention as the only international agreement by which to manage transboundary rivers,” said Li Lifeng, Director of Freshwater, WWF International.
“It should also convince countries to make more effort to protect and sustainably use their high altitude wetlands in the river source areas that WWF has been working on.”
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Adapted from materials provided by World Wildlife Fund.
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