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)

A group of San Bushmen from the Khomani San community practice their hunter-gatherer craft in the Southern Kalahari desert on October 15, 2009 in the Kalahari, South Africa. One of the largest studies of African genetics by an international team from the University of Pennsylvania, published in April 2009, revealed that the San of Southern Africa are the most genetically diverse on earth, and that the San homeland could be the spot where modern humanity began. (Photo by Dan Kitwood/Getty Images)

Sister Milly Wu (16) and Chloe Wu (18), both students from Manchester pose for photographs at the Hyper Japan 2012 Event at the Earls Court Exhibition Centre on February 24, 2012 in London, England. (Photo by Matthew Lloyd/Getty Images)

British comedian Elf Lyons performing her solo show, Talk Dirty, at Monkey Barrel Comedy club at Edinburgh festival in capital of Scotland on August 5, 2021. The Edinburgh international festival announced much-reduced programme this year. (Photo by Murdo MacLeod/The Guardian)

Right wing demonstrators chase a Black Lives Matter protester after a pro-Trump caravan rally convened at the Oregon State Capitol building on September 7, 2020 in Salem, Oregon. The caravan event, billed as the Oregon For Trump 2020 Labor Day Cruise Rally, began in Clackamas and made its way to the Oregon State Capitol in Salem. (Photo by David Ryder/Getty Images)

Montreal Canadiens defenseman Arber Xhekaj (72) fights with Ottawa Senators forward Mark Kastelic (47) during the first period at the Bell Centre in Montreal, Quebec on October 4, 2022. (Photo by Eric Bolte/USA TODAY Sports)

Meade forward Jaisean Kenner (21) hauls down a rebound against Sherwood forward Bryce Johnson (33) during the Class 4A boys' semifinals on March 8, 2023. (Photo by Jonathan Newton/The Washington Post)