गुरुवार, 17 अप्रैल 2008
Indus River dying a slow death owing to climate change
“India is named for the Indus River, along whose fecund banks a great urban civilisation flourished more than 4,000 years ago,” writes American historian Stanley Wolpert in his well-know book A New History of India. But the 3,000-kilometre-long river that is the lifeline of Pakistan’s economy is dying a slow death due to thinning of Tibetan glaciers and building of dams and barrages upstream.
The glaciers of the Tibetan plateau are vanishing so fast that they will be reduced by 50 per cent every decade, according to The Independent. Citing the leading Chinese scientists, it says the glaciers have been receding over the past four decades, as the world has gradually warmed up, but the process has now accelerated alarmingly. “The melting threatens to disrupt water supplies over much of Asia. Many of the continent’s greatest rivers-including the Yangtze, the Indus, the Ganges, the Brahmaputra, the Mekong and the Yellow River rise on the plateau,” the report says.
The Indus also has great heritage value and many fascinating names. In Tibet it is the Lion River issuing from the mouth of the Lion, in the gutter between the Karakoram and the Himalayas people call it ‘The Eastern River’, because it comes to them from the sunrise. It is also called ‘Abasin’, the Father of Rivers. In ancient times, says historian Jean Fairley, it was called ‘Sindhu’, meaning divider, keeper or defender, the name was gradually changed to Indus.
However, the grandiose of the River Indus is melting fast and points to a creeping emergency because it happens to be the main source of water supply to Pakistan’s major cities, including Karachi, besides irrigation. The situation can be gauged from the fact that freshwater availability in Pakistan has fallen from 5,200 cubic metres per capita in 1947 to less than 1,000 cubic metre currently, making it one of the most parched nations in the world.
The damming of the River Indus has further deteriorated the situation. “Before dams and barrages were built in the Indus Valley, the delta area was criss-crossed by the distributaries of the Indus. The discharge from the river was large enough to affect the ocean currents up to over a hundred miles from the shore. Due to this “an enormous quantity of freshwater and silt the river were brought with it and the delta lands became the richest in the area that constitutes Pakistan,” says noted town planner and architect, Arif Hasan.
The gradual but disastrous cut in the flow of freshwater to the Indus Delta has not only affected the lives and livelihood of the inhabitants of the once fertile delta, it has also led to sea intrusion up to 54km (36 miles) upstream along the main river course of the River Indus. “Nearly 1.6 million acres of agricultural land has been destroyed by sea intrusion,” says Mohammad Ali Shah, Chairman, Pakistan Fisherfolk Forum (PFF). As a result, tens of thousands of inhabitants of Indus Delta have been forced to migrate to greener pastures, including Ibrahim Hyderi, a fishing village in the suburbs of Karachi.
The lack of fresh water (down stream Kotri Barrage) has also badly affected the mangrove forests that happen to be the nurseries of shrimp and fish species. This indirectly affects the fishing industry of Pakistan that fetches $200 million per annum in terms of exports. “Studies have shown that some 60 per cent to 80 per cent of world’s commercial fisheries catch are mangrove dependent species,” says Tropical Rainforest Portfolio 1996-2001, a report prepared by the World Wide Fund (WWF) for Nature and the Netherlands government.
The precarious situation has been an outcome of the non-availability of freshwater downstream Kotri Barrage. This is amply demonstrated by the fact that the average annual and seasonal discharge downstream Kotri Barrage was 150 million acre feet (MAF) in 1880-92 but was merely 10MAF in 1992 due to building of dams and barrages upstream.
By Shahid Husain
http://www.thenews.com.pk/print1.asp?id=106526
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