Only a third of world’s great rivers remain free flowing, analysis finds.

Pedro_P

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Dams, levees, hydropower and habitat degradation behind fragmentation on huge scale, finds global assessment.

The Three Gorges Dam on the Yangtze river, Hubei province, China. Photograph: China Stringer Network/Reuters
▼ Only a third of the world’s great rivers remain free flowing, due to the impact of dams that are drastically reducing the benefits healthy rivers provide people and nature, according to a global analysis.
Billions of people rely on rivers for water, food and irrigation, but from the Danube to the Yangtze most large rivers are fragmented and degraded. Untouched rivers are largely confined to remote places such as the Arctic and Amazonia.
The assessment, the first to tackle the subject on a worldwide level, examined 12m kilometres of rivers and found that just 90 of the 246 rivers more than 1,000km (621 miles) long flowed without interruption.
The scientists, whose research, published in the journal Nature, was led by Günther Grill, at McGill University in Canada, were particularly concerned to discover that only a quarter of long rivers that once flowed freely to the sea, rather than to an inland lake or other river, still had such a course.
Separate research in Britain, which included the effects of smaller infrastructure such as weirs, fords and culverts, suggests that 97% of the  nation’s river networkhas been interrupted by human-built structures.
Thriving wildlife in rivers is crucial to keeping water clean but freshwater habitats were found to be the hardest hit of all the ecosystems, with wildlife populations having plunged by  an average of 83% since 1970due to dams, overuse of water and pollution.
“Free-flowing rivers are important for humans and the environment alike, yet economic development around the world is making them increasingly rare,” said Grill. “ (▪ ▪ ▪)

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soothsayer

very worrisome. The next War will be about water

ssangra

True a  very serious issue

warlikeprince

All over the world great rivers are depleted of Water. Water war is not far away from us. But some inter country rivers would be main reason for it. Many countries are thinking to restrict river flowing through their borders for themselves. Just like above example of China. China is also planning to build another dam over Brahmaputra River in Tibet (I don't know it's Chinese name) this would bring catastrophe to India and Bangladesh... International authorities should interven in this issue...

Manikant Kant

Everything has been polluted.  Air, water, earth (soil).  Space is littered with satellites.  Now of the five elements only fire can save.  

Rhett_Bassard

Manikant Kant 1-6-2019 08:41 AM
Everything has been polluted.  Air, water, earth (soil).  Space is littered with satellites.  Now of ...