Human damage to 80 percent of the world’s rivers threatens the water security of about 5 billion people, according to a study appearing in the September 30 issue of Nature.
And as many as 20,000 species of waterlife are at risk or face extinction because of human activities, the report says.
It’s the first global water study to examine combined human influences and their effects on water security and biodiversity. Scientists collected data on 23 human influences, such as pollution, dam construction, water extraction for irrigation, and introduction of alien fish species.
Scientists found that 30 of the planet’s 47 largest rivers have suffered at least moderate damage from human activities. The Yangtze, the Nile, the Ganges and the Mississippi rivers are among them. The researchers urged countries to invest in preventing damage to water sources, instead of the far more costly alternative of reversing damage once it has begun.
Read more at Rivers in Crisis.