Freshwater Ecosystem Services
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Free-flowing fresh water supports our most basic human needs.
It allows us to grow food. It generates hydropower. It permits the migration of fish that are eaten by hundreds of millions. It also allows us to ship goods around the world. |
Human Degradation
People withdrawing water from freshwater biomes cause them to shrink and degrade plant and animal habitats. Building dams and water diversion systems block fish migration routes and destroy irreplaceable plants and animals.
1.Nearly every major river in the world has been dammed, altering natural freshwater flows, cutting off migration routes and depleting fisheries downstream.
2.Nearly 40 percent of the rivers in the U.S. are too polluted for fishing and swimming.
3.Climate change, a growing global population, and increasing demands on water due to higher standards of living threaten to further burden our planet's freshwater systems.
4.Declines in native species and changes in freshwater food webs have been estimated to exceed US $100 million in lost income revenues.
Freshwater ecosystems have been modified through the creation of dams and through the withdrawal of water for human use. The construction of dams and other structures along rivers has strongly affected flows in 60% of the large river systems in the world. Water removal for human uses has reduced the flow of several major rivers, including the Nile, Yellow, and Colorado Rivers, to the extent that they do not always flow to the sea. As water flows have declined, so have sediment flows, which are the source of nutrients important for the maintenance of estuaries. Worldwide, sediment delivery to estuaries has declined by roughly 30%.
People withdrawing water from freshwater biomes cause them to shrink and degrade plant and animal habitats. Building dams and water diversion systems block fish migration routes and destroy irreplaceable plants and animals.
1.Nearly every major river in the world has been dammed, altering natural freshwater flows, cutting off migration routes and depleting fisheries downstream.
2.Nearly 40 percent of the rivers in the U.S. are too polluted for fishing and swimming.
3.Climate change, a growing global population, and increasing demands on water due to higher standards of living threaten to further burden our planet's freshwater systems.
4.Declines in native species and changes in freshwater food webs have been estimated to exceed US $100 million in lost income revenues.
Freshwater ecosystems have been modified through the creation of dams and through the withdrawal of water for human use. The construction of dams and other structures along rivers has strongly affected flows in 60% of the large river systems in the world. Water removal for human uses has reduced the flow of several major rivers, including the Nile, Yellow, and Colorado Rivers, to the extent that they do not always flow to the sea. As water flows have declined, so have sediment flows, which are the source of nutrients important for the maintenance of estuaries. Worldwide, sediment delivery to estuaries has declined by roughly 30%.