White whales and their trainers present a show for visitors at Harbin Pole Aquarium on January 7, 2014 in Harbin, China. Aquarium is one of the tourist highlights of Harbin, attract domestic and foreign tourists visit each year. (Photo by Lintao Zhang/Getty Images)

Costume actors to wait before the show at “Chian Tourism Day” Inauguration Ceremony in Ninghai Zhejiang Province on May 19, 2011 in Ninghai, China. Various activities in local famous historic sites are being held to mark the day “China Tourism Day” on May 19. (Photo by Lintao Zhang/Getty Images)

Tourists play at a beach covered by a thick layer of green algae in Qingdao, China, on July 3, 2013. A large quantity of non-poisonous green seaweed, enteromorpha prolifera, hit China's Qingdao coast last month. More than 20,000 tons of such seaweed has been removed from the city's beaches. This has now become an annual summer event. (Photo by Whitehotpix/ZumaPress.com)

Visitors walk through a tulip display in Chaya Mountain, Suiping County in Zhumadian, Henan Province of China on March 31, 2016. There are more than ten varieties of tulips here. (Photo by VCG/VCG via Getty Images)

A paramilitary police officer (right) turns around as hostesses line up for roll call ahead of the Beijing International Automotive Exhibition in Beijing, China, on Monday, April 25, 2016. Tesla Motors Inc. and BYD Co. are among manufacturers showing 147 new-energy vehicles at this year's show. (Photo by Qilai Shen/Bloomberg)

A seafood vendor moves a giant swordfish to his stall at a market in Qingdao, Shandong province, China, September 12, 2015. The 4.1-metre-long (13.5 feet) swordfish, weighed about 309.5 kilograms (682 lbs), was caught by local fishermen on Friday, local media reported. (Photo by Reuters/Stringer)

A model waits to present a creation by Chinese designer Hu Sheguang for his collection show during China Fashion Week S/S 2016 in Beijing October 26, 2015. (Photo by Jason Lee/Reuters)

Artist Kong Ning wears a wedding dress made from respirators to highlight concerns about air quality and pollution in Beijing, China on December 1, 2015. (Photo by Luo Xiaoguang/Xinhua Press/Corbis)