Contestants for the Miss World grand final perform in colourful costumes during a dress rehearsal in Sanya, Hainan province, China, 18 December 2015. (Photo by How Hwee Young/EPA)

Hospitality staff are reflected in a puddle of water as they prepare to pose for photograph in front of a giant basket decorated with replicas of flowers and fruits on display on Tiananmen Square during the opening ceremony of the 19th Party Congress in Beijing, Wednesday, October 18, 2017. Chinese President Xi Jinping on Wednesday urged a reinvigorated Communist Party to take on a more forceful role in society and economic development to better address “grim” challenges facing the country as he opened a twice-a-decade national congress. (Photo by Andy Wong/AP Photo)

Aerial view of CRH bullet trains setting out ahead of Spring Festival travel rush on January 31, 2018 in Hefei, Anhui Province of China. About 2.98 billion trips will be made during the 40-day Spring Festival travel rush. China will take multiple measures to ensure a smooth Spring Festival travel rush. (Photo by VCG/VCG via Getty Images)

A woman plays with a kitten inside of a line house in downtown Shanghai April 12, 2015. (Photo by Carlos Barria/Reuters)

Contestants of a tourism beauty pageant balance eggs on their collarbones as they cruise along the Yellow River in Jiyuan, Henan province, China, June 22, 2015. The contestants believe that if they are slim enough, their collarbones will allow them to balance the eggs securely on their bodies. (Photo by Reuters/Stringer)

A picture made with a tilt-shift lens shows “Dwarf Empire” cast member 19-year-old Han Zhen Yan posing in her fairy costume backstage outside one of the fairy tale-like houses at the Dwarf Empire theme park outside Kunming, China's Yunnan province, 04 April 2013. The Dwarf Empire theme park opened in mid-2009, employing a number of dwarves to create the show. Depending on what type of job they do at the park, employees earn between 800-2,000 CNY (100-250 Euros) per month, most of which goes towards their savings as lodging is provided, and their living quarters are equipped with kitchens where they prepare their own meals. (Photo by Diego Azubel/EPA)

A 22-year-old woman in a wedding gown is grabbed by Guo Zhongfan, a local community officer, as she attempts to kill herself by jumping out of a seven-storey residential building in Changchun, Jilin province. According to local media, the woman tried to commit suicide after her boyfriend of four years broke up with her, just as they were making plans to get married. The woman did not sustain any injuries during the incident. (Photo by China Daily/Reuters)

Yueyaquan is a crescent-shaped lake in an oasis, 6 km south of the city of Dunhuang in Gansu Province, China. It was named Yueyaquan in the Qing Dynasty. According to measurements made in 1960, the average depth of the lake was 4 to 5 meters, with a maximum depth of 7.5 metres In the following 40 years, the depth of the lake continually declined. In the early 1990s, its area had shrunk to only 5,500 m2 with an average depth of 0.9 meter (maximum 1.3 meter). In 2006, the local government with help of the central government started to fill the lake and restore its depth; its depth and size have been growing yearly since then. The lake and the surrounding deserts are very popular with tourists, who are offered camel and 4x4 rides.