Growing cities, overuse of fertilizers and factory wastewater have degraded China's water supplies to the extent that half the nation's rivers and lakes are severely polluted. China aims to spend $850 billion to improve filthy water supplies over the next decade, but even such huge outlays may do little to reverse damage caused by decades of pollution and overuse in Beijing's push for rapid economic growth. Photo: Fishermen row a boat in the algae-filled Chaohu Lake in Hefei, Anhui province, June 19, 2009. (Photo by Jianan Yu/Reuters)

Tokyo, “Electric City”. August 24, 2009. (Photo by Caribb; Source: Flickr)

A man rides a horse through a bonfire on January 16, 2009 in the small village of San Bartolome de Pinares, Spain. In honor of San Anton, the patron saint of animals, horses are riden trough the bonfires on the night before the official day of honoring animals in Spain. (Photo by Denis Doyle/Getty Images)

Christie's employee Natalie McFarlane holds an armature model of King Kong used in the 1933 film at Christie's on November 19, 2009 in London. (Photo by Peter Macdiarmid/Getty Images)

A group of children and their dog playing an Easter game in Cardiff. The game involves trying to eat an Easter egg off a piece of string without using their hands. (Photo by Richards/Fox Photos/Getty Images). 26th March 1937

A curious leopard cub toys with a camera at MalaMala Game Reserve in Mpumalanga Province, South Africa. (Photo by Barcroft Media)

Faces adorn crosses placed in the Garden of Remembrance of some of Britain's armed forces members who have died in Afghanistan in the Garden of Remembrance outside Westminster Abbey at the official opening of the Royal British Legion's Field of Remembrance on November 5, 2009 in London, England. (Photo by Alastair Grant-Pool/Getty Images)

Volunteers receive a professional massage from qualified therapists as they break a world record for the largest ever simultaneous massage during Massage en Masse at Lavandula Lavender Farm on March 30, 2010 in Daylesford, Australia. Two hundred and sixty three massage therapists each massaged a volunteer, breaking the former world record of 167, set in 2009 in Washington DC. (Photo by Scott Barbour/Getty Images)