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)

This artist's scoreboard displays a fictional game between Mars and Earth, with Mars in the lead. It refers to the success rate of sending missions to Mars, both as orbiters and landers. Of the previous 39 missions targeted for Mars from around the world, 15 have been successes and 24 failures. For baseball fans, that's a batting average of .385. The United States has had 13 successes out of 18 attempts, or a “batting average” of .722. NASA's Curiosity rover, set to land on the Red Planet the evening of Aug. 5, 2012 PDT (morning of Aug. 6 EDT), will mark the United States' 19th attempt to tackle the challenge of Mars, and the world's 40th attempt. (Image by NASA/JPL-Caltech)

A paddler races in a giant pumpkin during the annual regatta on Lake Pisiquid in Windsor, Nova Scotia, Sunday, October 11, 2015. Participants hollow out the massive gourds and pilot them across the 500 meter course. (Photo by Andrew Vaughan/The Canadian Press via AP Photo)

A mother prays for success for her child in the college entrance examinations at a Buddhist temple in Seoul, South Korea, November 12, 2015. About 630,000 students on Thursday sat for the annual exams that could lead them to one of the country's top universities. In South Korea, there is no higher achievement than to be accepted by a prestigious university. As a result, many students prepare for these entrance exams from an early age, often studying up to 16 hours a day for years to take this test. (Photo by Kim Hong-Ji/Reuters)

Revellers take part in the the 70th Annual Columbus Day Parade in New York, October 13, 2014. (Photo by Eduardo Munoz/Reuters)

Chinese Kazakh eagle hunters sit on horseback as they travel to a local competition on January 29, 2015 in the mountains of Qinghe County, Xinjiang, northwestern China. The festival, organised by the local hunting community, is part of an effort to promote and grow traditional hunting practices for new generations in the mountainous region of western China that borders Kazakhstan, Russia and Mongolia. The training and handling of the large birds of prey follows a strict set of ancient rules that Kazakh eagle hunters are preserving for future generations. (Photo by Kevin Frayer/Getty Images)

French actress Marie Cornillon wearing body paint and a headgear with bull horns, poses in front of the Nimes arena with a sign inscribed “Abolissons la corrida” (Abolish corrida bullfighting) as part of a protest by the People for the Ethical Treatment of Animals (PETA) animal rights group to ban bullfighting in France, on November 16, 2022. (Photo by Pascal Guyot/AFP Photo)

A woman promotes a go-go dance bar in Pattaya, Thailand March 25, 2017. With mascots dressed as smiling fish and a police rock band, Thai authorities launched a “Happy Zone” at the weekend to improve the image of a city notorious for sеx tourism. Stung by foreign headlines portraying the seaside resort of Pattaya as “Sin City” and “The World’s Sеx Capital”, Thailand’s junta has begun a new effort to re-brand it. Businesses in the Happy Zone are asked to make the area feel safer, there are increased security patrols, police launched a mobile phone app for visitors to summon them if an emergency occurs. (Photo by Jorge Silva/Reuters)