Chinese women ride a bicycle together on a street September 10, 2014 in Beijing, China. (Photo by Kevin Frayer/Getty Images)

Child models present creations at Dong Wenmei T100 Children's Collection during China Fashion Week in Beijing October 29, 2014. (Photo by Kim Kyung-Hoon/Reuters)

It’s a tradition that dates back hundreds of years, where two stallions fight over a female to ring the Chinese new year. And when it’s the Year of the Horse, the fights are considered to be even more significant. They’re held in small villages across southern China and have been condemned by animal rights groups, including Hong-Kong based Animals Asia. But those who participate in the events defend the fights and insist they take care of the animals.

Participants take pictures of themselves as others run past the Tiananmen gate during the Beijing Marathon in Beijing, China, September 17, 2016. (Photo by Damir Sagolj/Reuters)

Paramilitary policemen carry tyres as they take part in a training session in Zhangye, Gansu Province, China, March 1, 2016. (Photo by Reuters/Stringer)

A man wearing a mask and dressed in a clown costume rides an electric tricycle while carrying a container in the shape of a rubber duck amid heavy smog in Beijing, China, December 29, 2015. (Photo by Jason Lee/Reuters)

A woman scales fish by the side of a lake as she prepares for the upcoming Chinese Lunar New Year in Suqian, Jiangsu province, China, January 27, 2016. (Photo by Reuters/China Daily)

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)